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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.
31

Economic Pricing of Mortality-Linked Securities

Zhou, Rui January 2012 (has links)
In previous research on pricing mortality-linked securities, the no-arbitrage approach is often used. However, this method, which takes market prices as given, is difficult to implement in today's embryonic market where there are few traded securities. In particular, with limited market price data, identifying a risk neutral measure requires strong assumptions. In this thesis, we approach the pricing problem from a different angle by considering economic methods. We propose pricing approaches in both competitive market and non-competitive market. In the competitive market, we treat the pricing work as a Walrasian tâtonnement process, in which prices are determined through a gradual calibration of supply and demand. Such a pricing framework provides with us a pair of supply and demand curves. From these curves we can tell if there will be any trade between the counterparties, and if there will, at what price the mortality-linked security will be traded. This method does not require the market prices of other mortality-linked securities as input. This can spare us from the problems associated with the lack of market price data. We extend the pricing framework to incorporate population basis risk, which arises when a pension plan relies on standardized instruments to hedge its longevity risk exposure. This extension allows us to obtain the price and trading quantity of mortality-linked securities in the presence of population basis risk. The resulting supply and demand curves help us understand how population basis risk would affect the behaviors of agents. We apply the method to a hypothetical longevity bond, using real mortality data from different populations. Our illustrations show that, interestingly, population basis risk can affect the price of a mortality-linked security in different directions, depending on the properties of the populations involved. We have also examined the impact of transitory mortality jumps on trading in a competitive market. Mortality dynamics are subject to jumps, which are due to events such as the Spanish flu in 1918. Such jumps can have a significant impact on prices of mortality-linked securities, and therefore should be taken into account in modeling. Although several single-population mortality models with jump effects have been developed, they are not adequate for trades in which population basis risk exists. We first develop a two-population mortality model with transitory jump effects, and then we use the proposed mortality model to examine how mortality jumps may affect the supply and demand of mortality-linked securities. Finally, we model the pricing process in a non-competitive market as a bargaining game. Nash's bargaining solution is applied to obtain a unique trading contract. With no requirement of a competitive market, this approach is more appropriate for the current mortality-linked security market. We compare this approach with the other proposed pricing method. It is found that both pricing methods lead to Pareto optimal outcomes.
32

Skirtingo amžiaus ir lyties orientacininkų kojų raumenų galingumas ir vargstamumas atliekant vertikalius šuolius / Muscle power and fatigue resistance during vertical jumping in orienteers of different age and gender

Jusas, Giedrius 16 August 2007 (has links)
Tyrimo tikslas – nustatyti įvairaus amžiaus ir lyties orientacininkų kojų tiesiamųjų raumenų galingumą ir atsparumą nuovargiui vertikalaus šuoliavimo testo metu. Buvo ištirti 92 orientacininkai, pagal amžių (metais) ir lytį (moteriška, M; vyriška, V) suskirstyti į šešias grupes: M15–17 merginos (n = 19), M18–20 merginos (n = 9), M>21 moterys (n = 4), V15–17 jaunuoliai (n = 21), V18–20 vaikinai (n = 18), V > 21 vyrai (n = 21). Vertikalių šuolių aukštį matavome pagal C. Bosco metodiką. Po standartinės pramankštos tiriamieji ant 60x60 cm dydžio kontaktinio kilimėlio atliko po tris vienkartinius maksimalių pastangų vertikalius šuolius su rankų mostu ir be mosto, o paskui 60 s šuoliavo maksimaliomis pastangomis, amortizuojamai pritūpdami iki 90° kampo per kelius (rankas laikydami ant juosmens). Vienkartinio vertikalaus šuolio aukštis (taigi ir kojų tiesiamųjų raumenų galingumas) nepriklausė nuo amžiaus, tačiau visose amžiaus grupėse vyriška lytis tiriamieji pašokdavo aukščiau. Lyginant orientacininkių gebėjimą aukštai pašokti su rankų mostu ir be mosto, reikšmingus pašokimo aukščio skirtumus nustatėme 15–17 ir 18–20 metų amžiaus orientacininkių grupėse, o tarp orientacininkų šis skirtumas buvo reikšmingas visose amžiaus grupėse (p < 0,001). Išanalizavę šuolių aukščio kaitą 1 min. šuoliavimo testo metu pastebėjome, kad statistiškai reikšmingi vargstamumo skirtumai amžiaus aspektu buvo tik tarp M15–17 ir M18–20 grupių (p < 0,05), o lyties aspektu – tarp M15–17 ir V15–17 grupių... [toliau žr. visą tekstą] / The aim of the study was to estimate vertical jumping performance in orienteers of various age and both sexes. The study embraced 92 orienteers of national level. According to age (years) and gender (males, M; females, F), six groups of athletes were singled out: F15–17 (n = 19), F18–20 (n = 9), F>21 (n = 4), M15–17 (n = 21), M18–20 (n = 18), and M>21 (n = 21). After a standard warm-up, subjects performed maximal intensity vertical jumps on the contact mat sized 60x60 cm. After orienteers made jumps with and without arm swing (3 attempts each), all-out vertical jumps for 60 sec with a shock-absorbing squat to 90° knee angle, arms akimbo, were performed. The jump height was measured according to C. Bosco et al., using a flight-phase time as a sole indicator. There were no statistically significant differences in the height of the single vertical jump between age groups, irrespectively of the gender. However, statistically significant differences were observed in the height of the single vertical jump in all age groups in respect to gender. The comparison of vertical jumps performed by females with and without arm swing revealed statistically significant difference only between F15–17 and F18–20 groups, while the difference in jump height between two modes was statistically significant in male orienteers of all age groups (p < 0.001). F15–17 and F18–20 groups differed in respect to fatigue index during 60 sec test (p < 0.05). The different fatigue index was observed in respect... [to full text]
33

Economic Pricing of Mortality-Linked Securities

Zhou, Rui January 2012 (has links)
In previous research on pricing mortality-linked securities, the no-arbitrage approach is often used. However, this method, which takes market prices as given, is difficult to implement in today's embryonic market where there are few traded securities. In particular, with limited market price data, identifying a risk neutral measure requires strong assumptions. In this thesis, we approach the pricing problem from a different angle by considering economic methods. We propose pricing approaches in both competitive market and non-competitive market. In the competitive market, we treat the pricing work as a Walrasian tâtonnement process, in which prices are determined through a gradual calibration of supply and demand. Such a pricing framework provides with us a pair of supply and demand curves. From these curves we can tell if there will be any trade between the counterparties, and if there will, at what price the mortality-linked security will be traded. This method does not require the market prices of other mortality-linked securities as input. This can spare us from the problems associated with the lack of market price data. We extend the pricing framework to incorporate population basis risk, which arises when a pension plan relies on standardized instruments to hedge its longevity risk exposure. This extension allows us to obtain the price and trading quantity of mortality-linked securities in the presence of population basis risk. The resulting supply and demand curves help us understand how population basis risk would affect the behaviors of agents. We apply the method to a hypothetical longevity bond, using real mortality data from different populations. Our illustrations show that, interestingly, population basis risk can affect the price of a mortality-linked security in different directions, depending on the properties of the populations involved. We have also examined the impact of transitory mortality jumps on trading in a competitive market. Mortality dynamics are subject to jumps, which are due to events such as the Spanish flu in 1918. Such jumps can have a significant impact on prices of mortality-linked securities, and therefore should be taken into account in modeling. Although several single-population mortality models with jump effects have been developed, they are not adequate for trades in which population basis risk exists. We first develop a two-population mortality model with transitory jump effects, and then we use the proposed mortality model to examine how mortality jumps may affect the supply and demand of mortality-linked securities. Finally, we model the pricing process in a non-competitive market as a bargaining game. Nash's bargaining solution is applied to obtain a unique trading contract. With no requirement of a competitive market, this approach is more appropriate for the current mortality-linked security market. We compare this approach with the other proposed pricing method. It is found that both pricing methods lead to Pareto optimal outcomes.
34

Using Video Feedback to Increase Figure Skaters' Performance

Greenberg, Lori 22 March 2018 (has links)
Figure skating is a competitive sport that requires intensive training which can be taught in a variety of settings. There are various methods to teaching figure skaters new skills such as positive and corrective feedback, modeling and coaching procedures, and physical guidance. These different approaches may lead to a lack of consistency among coaches. Over the years, these established coaching strategies have not changed substantially as training methods are passed down from coach to student. Also, research in the area of what constitutes effective coaching methods is lacking. Skaters may progress more quickly in skill development if coaches are implementing empirically based successful coaching methods. These teaching approaches may also be enhanced by incorporating the latest technology available. This study evaluated the effectiveness of a video feedback coaching procedure using the Dartfish application. A multiple baseline design was utilized to document the impact of this video feedback coaching procedure on the demonstration of six established figure skating moves, three moves for one skater and three different moves for two other skaters. Results showed utilizing video feedback improved figure skater's performance levels on the targeted moves to an acquisition of 80% accuracy or higher.
35

Estudos de avalanches de vórtices em filmes supercondutores de Nb e MgB2

Colauto, Fabiano 28 October 2008 (has links)
Made available in DSpace on 2016-06-02T20:15:19Z (GMT). No. of bitstreams: 1 2063.pdf: 4236458 bytes, checksum: 6ec4d9bb25ad55b37fc22de7495a85d9 (MD5) Previous issue date: 2008-10-28 / Universidade Federal de Minas Gerais / If a type-II superconductor is cooled down in a zero applied field and subsequently an external field, larger than the first critical field, is applied, vortices enter through the sample borders until they are captured by pinning centers. As a consequence, the system achieves an inhomogeneous flux distribution, with a higher density of vortices near the border that progressively decreases toward the center of the sample. Under a small perturbation this self-organized state can lead to vortex avalanches that rush into the sample due to a thermomagnetic instability process. The motion of magnetic flux generates heat, which suppresses flux pinning and facilitates further flux motion. This provides a positive feedback mechanism that can result in a thermal runaway. The experimental study was accomplished through two techniques: bulk DC magnetometry and magneto-optical imaging. Under certain circumstances, avalanches develop as jumps in magnetization measurements and can also be seen in real time imaging. We have carried out a systematic study of the parameters involved in the occurrence of flux avalanches in superconducting thin films, submitted to perpendicular magnetic fields, a geometry which leads to dendritic profiles of flux penetration. The threshold values of field and temperature that encompass the region where avalanches to develop, as well as the instability boundary dependence on the film thickness, were identified. We have verified how an AC magnetic field influences on vortex avalanches and on the boundaries of instabilities. The study was also performed with an aluminum disk nearby the superconducting film, which suppresses vortex avalanches partially or totally, depending on the distance between film and disk, bringing the material to recover its capability of screening abrupt penetration of magnetic flux. / Se um supercondutor do tipo II for resfriado na ausência de um campo magnético e, posteriormente, um campo externo maior do que o campo crítico inferior, for aplicado, vórtices penetram pelas bordas até serem ancorados por centros de aprisionamento. Como conseqüência, o sistema alcança uma distribuição de fluxo inomogênea, com uma alta densidade de vórtices próxima às bordas, que diminui progressivamente em direção ao centro da amostra. Sob uma pequena perturbação este estado auto-organizado pode levar a avalanches de vórtices, que são precipitadas em decorrência de um processo de instabilidade termomagnética. O movimento do fluxo magnético promove um aquecimento, que suprime as forças de ancoramento dos vórtices e facilita o movimento adicional do fluxo nas suas vizinhanças. Esta dinâmica se realimenta positivamente e pode resultar num descontrole térmico. O estudo experimental foi realizado empregando duas técnicas: magnetometria volumétrica DC e produção de imagens por magneto-ótica. Em certas circunstâncias, as avalanches se manifestam como saltos nas medidas de magnetização e também podem ser visualizadas em tempo real através de imagens. Executamos um estudo sistemático dos parâmetros envolvidos na ocorrência das avalanches de fluxo em filmes supercondutores, submetidos a campos magnéticos perpendiculares, geometria que propicia um perfil dendrítico de penetração. Identificamos os valores limiares de campo e temperatura que delimitam a região onde as avalanches ocorrem e a dependência do contorno desta região com a espessura do filme. Verificamos o efeito de um campo magnético alternado na ocorrência das avalanches e no contorno da região de instabilidades. O estudo se estendeu também à investigação da influência de um disco de alumínio nas proximidades do filme supercondutor, o qual suprime as avalanches de vórtices de forma parcial ou total, dependendo de sua distância em relação ao filme, recapacitando o material a blindar penetrações abruptas de fluxo magnético.
36

Filtro de mínimos quadrados e filtro robusto para sistemas lineares com saltos Markovianos e ruídos multiplicativos. / Kalman type filter and robust filter to linear filter to linear systems subject to Markovian jumps and multiplicative noises.

Guilherme Rafael Antonelli Molina Benites 08 November 2012 (has links)
Esse trabalho contempla o estudo sobre o estimador de mínimos quadrados obtido para sistemas lineares discretos sujeitos a ruídos aditivos e a ruídos multiplicativos em seus parâmetros. Supõe-se, adicionalmente, que os parâmetros do sistema estão sujeitos a saltos Markovianos, e que a cadeia de Markov não é conhecida. A solução do problema, sob essas hipóteses, é uma inovação apresentada nesse trabalho. Sob as mesmas hipóteses, o caso estacionário também foi contemplado, e o trabalho apresenta uma demonstração para a convergência da matriz de covariância dos erros do estimador a um valor estacionário, supondo-se estabilidade do sistema e ergodicidade da cadeia de Markov associada. Mostra-se, também, que existe uma única solução positiva semi-definida para a equação de Riccati estacionária e, ainda mais, que tal solução é o limite da matriz de covariância dos erros. A partir da introdução de uma hipótese adicional - de que os parâmetros do sistema estão sujeitos a incertezas na forma de politopos convexos - constrói-se um filtro linear dinâmico em que as iterações possuem estabilidade na média quadrática e que minimiza o limitante superior para o valor esperado do erro quadrático. Uma formulação do tipo LMI (Linear Matrix Inequalities) é proposta para a solução do problema. / This thesis deals with the linear filtering problem for discrete-time Markov jump linear systems with both additive and multiplicative noises. It is assumed that the values of the Markov chain are not available. This is the first time that a solution to the problem with these parameters is presented. By using some usual geometric arguments it is obtained a Kalman type filter conveniently implementable in a recurrence form. The stationary case is also studied and a proof for the convergence of the associated Lyapunov and Riccati like equations is presented. By adding an additional hypotesis - that the parameters of the systems are subject to convex polytopic uncertainties - it was designed a dynamic linear filter such that the closed loop system is mean square stable and minimizes an upper bound for the stationary expected value of the square error. A Linear Matrix Inequalities (LMI) formulation is proposed to solve the problem.
37

Spillovers and jumps in global markets: a comparative analysis / Saltos e Spillovers nos mercados globais: uma análise comparativa

Rodolfo Chiabai Moura 08 June 2018 (has links)
We analyze the relation between volatility spillovers and jumps in financial markets. For this, we compared the volatility spillover index proposed by Diebold and Yilmaz (2009) with a global volatility component, estimated through a multivariate stochastic volatility model with jumps in the mean and in the conditional volatility. This model allows a direct dating of events that alter the global volatility structure, based on a permanent/transitory decomposition in the structure of returns and volatilities, and also the estimation of market risk measures. We conclude that the multivariate stochastic volatility model solves some limitations in the spillover index and can be a useful tool in measuring and managing risk in global financial markets. / Analisamos a relação existente entre spillovers e saltos na volatilidade nos mercados financeiros. Para isso, comparamos o índice de spillover de volatilidade proposto por Diebold and Yilmaz (2009), com um componente de volatilidade global, estimado através de um modelo multivariado de volatilidade estocástica com saltos na média e na volatilidade condicional. Este modelo permite uma datação direta dos eventos que alteram a estrutura de volatilidade global, baseando-se na decomposição das estruturas de retorno e volatilidade entre efeitos permanentes/transitórios, como também a estimação de medidas de risco de mercado. Concluímos que este modelo resolve algumas das limitações do índice de spillover além de fornecer um método prático para mensurar e administrar o risco nos mercados financeiros globais.
38

Une équation stochastique avec sauts censurés liée à des PDMP à plusieurs régimes / A stochastic equation with censored jumps related to multi-scale Piecewise Deterministic Markov Processes

Rabiet, Victor 23 June 2015 (has links)
L'ensemble de ce travail est dédié à l'étude de certaines propriétés concernant les processus de sauts d-dimensionnels X = (Xt) dont le générateur est donné par Lψ(x) = 1/2 ∑ aᵤᵥ(x)∂²ψ(x)/∂xᵤ∂xᵥ + g(x)∇ψ(x) + ∫ (ψ(x + c(z, x)) − ψ(x))γ(z, x)µ(dz) où µ est de masse totale infinie. Si γ ne dépendait pas de x, nous nous trouverions dans une situation classique où le processus X pourrait être représenté comme une solution d'une équation stochastique comportant une mesure ponctuelle de Poisson de mesure d'intensité γ(z)µ(dz) ; lorsque γ dépend de x, on peut s'en représenter l'heuristique en imaginant le processus comme la trajectoire d'une particule, la loi des sauts pouvant alors dépendre de la position de la particule. Dans la première partie, nous donnons des conditions pour obtenir l'existence et l'unicité de tels processus. Ensuite, nous considérons ce type de processus comme une généralisation des PDMP ; nous montrons qu'ils peuvent être vus comme une limite d'une suite (Xᵣ(t)) de PDMP standards pour lesquels l'intensité des sauts tend vers l'infini quand r tend vers l'infini, suivant deux régimes : un lent et un rapide qui, en supposant que les processus en question sont centrés et normalisés convenablement, produit une composante de diffusion à la limite. Finalement, on prouve la récurrence au sens de Harris de X en utilisant un schéma régénératif entièrement basé sur les sauts du processus. De plus, nous dégageons des conditions explicites par rapport aux coefficients du processus qui nous permettent de contrôler la vitesse de convergence vers l'équilibre en terme d'inégalités de déviation pour des fonctionnelles additives intégrables. Dans la seconde partie, nous considérons à nouveau le même type de processus X = (Xt(x)) partant du point x. Utilisant une approche basé sur un Calcul de Malliavin fini-dimensionnel, nous étudions la régularité jointe de ce processus dans le sens suivant : on fixe b≥1 et p>1, K un ensemble compact de Rᵈ, et nous donnons des conditions suffisantes pour avoir P(Xt(x)∈dy)=pt(x,y)dy avec (x,y)↦pt(x,y) appartenant à Wᵇᵖ(K×Rᵈ) / This work is dedicated to the study of some properties concerning the d-dimensional jump type diffusion X = (Xt) with infinitesimal generator given by Lψ(x) = 1/2 ∑ aᵤᵥ(x)∂²ψ(x)/∂xᵤ∂xᵥ + g(x)∇ψ(x) + ∫ (ψ(x + c(z, x)) − ψ(x))γ(z, x)µ(dz) where µ is of infinite total mass. If γ did not depend on x, we would be in a classical situation where the process X could be represented as the solution of a stochastic equation driven by a Poisson point measure with intensity measure γ(z)µ(dz) ; when γ depends on x, we may have the heuristic idea that, if we were to imagine the process as a trajectory of a particle, the law of the jumps may depend on the position of the particle. In the first part, we give some conditions to obtain existence and uniqueness of such processes. Then, we consider this type of processes as a generalization of Piecewise Deterministic Markov Processes (PDMP) ; we show that they can be seen as a limit of a sequence (Xᵣ(t)) of standard PDMP's for which the intensity of the jumps tends to infinity as r tends to infinity, following two regimes: a slow one, which leads to a jump component with finite variation, and a rapid one which, supposing that the processes at hand are centered and renormalized in a convenient way, produces the diffusion component in the limit. Finally, we prove Harris recurrence of X using a regeneration scheme which is entirely based on the jumps of the process. Moreover we state explicit conditions in terms of the coefficients of the process allowing to control the speed of convergence to equilibrium in terms of deviation inequalities for integrable additive functionals. In the second part, we consider again the same type of process X = (Xt(x)) starting from x. Using an approach based on a finite dimensional Malliavin Calculus, we study the joint regularity of this process in the following sense : we fix b≥1 and p>1, K a compact set of Rᵈ, and we give sufficient conditions in order to have P(Xt(x)∈dy)=pt(x,y)dy with (x,y)↦pt(x,y) in Wᵇᵖ(K×Rᵈ)
39

Vybrané kondiční aspekty profesionálních hasičů soutěžících v požárním sportu a TFA / Selected fitness aspects of professional firefighters competing in fire sport and TFA

Miřátský, Petr January 2018 (has links)
Title: Selected fitness aspects of professional firefighters competing in fire sport and TFA Objectives: The aim of the thesis was to find out the level and the difference in the parameters of body constitution, postural stability and muscular and explosive force of lower limbs with groups of professional firemen competing in fire sport and TFA Methods: The research sample was represented by two groups of professional firemen (17 fire sportsmen and 17 TFA competitors). We assessed chosen parameters of body constitution (Tanita MC-980MA), postural stability (RS Footscan), explosive force (Kistler) and muscular force (Cybex Humac Norm). Assessed parameters of body constitution were percentage of body fat and fatless matter. In the tests of postural stability we assessed total travel way of the centre of pressure (TTW), narrow stand (open and closed eyes) and one-leg stand (right, left). When testing explosive force, overall produced maximal force and height of the leap were assessed. Muscular force was assessed with the help of muscular force moment in concentric muscle activity with angular velocity 60ř·s-1. Results: We found out a significant difference between the two groups in the tests of postural stability - narrow stand with open and closed eyes (F1,32 = 9,94, p<0,01), in the tests of...
40

Effects of Short-Term Resistance Training on Adult Men and Women with and without Metabolic Syndrome.

South, Mark Allen 18 December 2010 (has links) (PDF)
Resistance training can alter a number of health-related and performance variables. These alterations include beneficial effects on body composition, blood pressure, and blood lipids and enhanced maximum strength, rate of force development, and power. These enhancements may translate into a better quality of life. As a result, resistance training can be used as a valuable tool in ameliorating the effects of a sedentary lifestyle, including those associated with metabolic syndrome. Nineteen subjects (10 metabolic syndrome, 9 previously sedentary nonmetabolic syndrome) underwent 8 weeks of supervised resistance training. After training, strength and V̇O2 peak increased by approximately 10% in the metabolic and nonmetabolic syndrome groups and the male and female groups. Percent body fat decreased in subjects with the metabolic syndrome and in females. Additionally, lean body mass increased in all groups (p<0.05). Eight weeks of resistance training improves several cardiovascular risk factors of metabolic syndrome.

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