211 |
The Prodromal Phase of What? : A Metapsychiatric Analysis of the Prodromal Phase of Schizophrenia / Prodromalfasen av vad? : En Metapsykiatrisk Analys av Prodromalfasen till SchizofreniNeubeck, Anna-Karin January 2008 (has links)
Prodromes of schizophrenia or prodromes of psychosis are a relatively new and expanding field of interest in psychiatric research. They are seen by some researchers as the initial symptom of having schizophrenia and have become a crucial topic in early psychosis research and intervention. In this thesis current psychiatric research publications were analysed and eleven prospectively psychotic patients were interviewed. The research publications analysed were applyed on the information given by the patients, and the analysis showed that it was easy to find prodromes or prodrome-like phenomena in all the collected interviews. In addition a second analysis was performed on the material, a phenomenological psychological analysis, showing a more subject-oriented dimension of the interviews. This led to a further aim, analysing what explanations could be given of these phenomena. There are probably many possibilities of getting the diagnosis of schizophrenia, but the examples in this study show that long-term abuse, often sexual actually can trigger psychiatric conditions corresponding to the definition of “prodromes of schizophrenia” according to some psychiatric publications as well as “schizophrenia” according to DSM and ICD. This means that trauma and/or neglect proved to be a likely partial causal condition of the prodrome- like phenomena or schizophrenia to occur. However, trauma has not been shown to be a necessary condition for the occurrence of prodrome-like phenomena or schizophrenia. In the discussion of the results some consequences deriving from using different interpretations and explanations of the phenomena are analysed, for example using the prodromes of psychosis for the assessments of a coming psychosis, especially schizophrenia. I emphasize, because of the results of the phenomenological case analyses, the value of several dimensions of understanding prodrome-like phenomena as well as schizophrenia and schizophrenia-like conditions, especially as early as the initial phase. / Prodromalfasen till schizofreni är ett relativt nytt begrepp och det utgör ett expanderande intresseområde för psykiatrisk forskning. Förändringar i prodromalfasen ses av vissa forskare som de första tecknen på schizofreni, och dessa fenomen har kommit i fokus speciellt vad gäller tidig upptäckt och intervention inom schizofreniforskning. I denna avhandling analyseras åtskilliga psykiatriska texter som behandlar prodromalfasens fenomen. I den empiriska studien har elva personer, som senare utvecklat psykotiska symtom, intervjuats. Två etablerade listor på prodromalfenomen testades på det empiriska materialet. Resultaten av den analysen visade att de gick att finna prodromalliknande fenomen hos alla intervjuade patienter. En andra fenomenologisk och mer subjektorienterad analys av det empiriska materialet genomfördes parallellt. Resultaten av de två analyserna ledde till ett tredje fokus för avhandlingen, nämligen frågan om möjliga kausalförklaringar till de prodromalliknande fenomenen. Det finns förmodligen många orsaker till att en person uppvisar symtom som överensstämmer med diagnosen schizofreni. Exemplen i denna studie visar dock att långvariga, ofta sexuella, övergrepp kan leda till psykiatriska tillstånd som överensstämmer med fenomen i prodromalfasen och med själva diagnosen schizofreni enligt kriterierna i DSM-IV och ICD-10. Avhandlingens huvudhypotes är således att svåra trauman utgör delorsaker både till prodromalliknande fenomen liksom till tillstånd som diagnosticerats som schizofreni. Avhandlingens resultat ger dock ingen anledning att anta att trauman utgör nödvändiga betingelser för schizofreni. I avhandlingens resultatdiskussion lyfter författaren fram några viktiga konsekvenser av olika definitioner av begreppen prodromalfenomen och schizofreni bl a vad avser förslag till terapeutiska interventioner. Mot bakgrund av resultaten från den fenomenologiska analysen understryks vikten av en bred förståelse av prodromalliknande fenomen liksom av fenomen som diagnosticeras som schizofreni.
|
212 |
Integrated investigation of impact-induced noise and vibration in vehicular drivetrain systemsGnanakumarr, Max Mahadevan January 2004 (has links)
This thesis highlights one of the most significant concerns that has preoccupied drivetrain engineers in recent times, namely drivetrain clonk. Clonk is an unacceptable audible sound, which is accompanied by a tactile drivetrain response. This may occur under several different driving conditions. Many drivetrain NVH concerns are related to impact loading of subsystems down-line of engine. These concerns are induced by power torque surge through engagement and disengagement processes, which may propagate through various transmission paths as structural waves. The coincidence of these waves with the acoustic modes of sub-system components leads to audible responses, referred to as clonk. The approach usually undertaken and reported in literature is either purely theoretical or constitutes experimental observation of vehicle conditions. A few research workers have reported rig-based investigations, but not under fully dynamic conditions with controlled and reproducible impulsive action. The research reported in this thesis combines experimental and numerical investigation of high frequency behaviour of light truck drivetrain systems, when subjected to sudden impulsive action, due to driver behaviour. The problem is treated as a multi-physics interactive phenomenon under transient conditions. The devised numerical method combines multi-body dynamics, structural modal analysis, impact dynamics in lash zones and acoustic analysis within an overall investigation framework. A representative drivetrain system rig is designed and implemented, and controlled tests simulating driver behaviour undertaken. The combined numerical predictions and experimental noise and vibration monitoring has highlighted the fundamental aspects of drivetrain behaviour. Good agreement is' also found between the detailed numerical approach and the experimental findings. Novel methods of measurement such as Laser Doppler Vibrometery have been employed. Simultaneous measurements of vibration and noise radiation confirm significant elasto-acoustic coupling at high impact energy levels. One of the major finds of the thesis is the complex nature of the clonk signal, being a combination of accelerative and ringing noise, with the latter also comprising of many other lower energy content as observed in the case of transmission rattle and bearing-induced responses. Therefore, the link between rattle and clonk, long suspected, but not hitherto shown has been confirmed in the thesis. Another major find of particular commercial interest is the insignificant contribution of torsional damping devices such as dual mass flywheels upon the accelerative component of the clonk response.
|
213 |
Historický vývoj kulturního fenoménu "James Bond" na pozadí studené války / The History of the Cultural Phenomenon "James Bond" on the Background of the Cold WarKříž, Jaroslav January 2013 (has links)
The thesis analyzes a historical development of James Bond films in a background of the Cold War between years 1962-1989. A fictional character James Bond is a cultural phenomenon, which became an absolute world-wide symbol from the point of popular culture since the sixties in 20 century. The main part of the thesis focuses on movies with agent 007 and describes the ideological base, which we can investigate. Secondarily, Bond's past is handled. Therefore, a development of the literary figure, who moved from spy novels to the screen, is analyzed in here. Further, parts of the thesis mention social background, which was greatly influenced by Bond topic in the second half of the 20th century. Powered by TCPDF (www.tcpdf.org)
|
214 |
Varning för clown : En kvalitativ textanalys av tidningsmediers framställning av clownattackerna i Sverige 2016 / Beware of clowns : A qualitative textual analysis of newspapermedia's representation of the clown attacks in Sweden in 2016Ekryd, Lovisa, Einebrant, Evelyn January 2017 (has links)
Hösten 2016 uppkom ett fenomen som blev omtalat i svenska morgontidningar, den så kallade “clownhysterin”. Fenomen sattes snabbt på agendan och handlade om clowner som hade attackerat människor. Syftet med denna studie är att undersöka vilka som får synas i artiklarna och hur de representeras. Artiklarna kommer att inhämtas från de två största kvälls- och morgontidningar i Sverige, Aftonbladet och Dagens Nyheter. Studien använder sig av teorin om medielogiken där begreppen tillspetsning, förenkling, polarisering, intensifiering, personifiering, konkretion och stereotypisering använts. En kvalitativ textanalys kommer att vara studiens metod. Resultaten som tagits fram visar på att vittnen, clowner och utsatta är underrepresenterade i artiklarna. Poliser och högre uppsatta syns till en större grad. Clownerna representeras som de onda och skräckinjagande medan poliser framställs som tillförlitliga och sakliga. / In the fall of 2016 the words “creepy clown hysteria” or “clown attacks” became regular to the Swedish daily press. The phenomenon of clowns attacking people and scaring people became media's head priority during approximately two weeks. The focus of this thesis is to establish who gets to talk in the articles and how these people are represented. The articles are found in the biggest night and morning newspapers, Aftonbladet and Dagens Nyheter. The theory for this thesis is called media logics and includes seven directions, these are; sharpening, simplification, polarization, intensification, personification, concreteness and stereotyping. A qualitative text analysis is used as method for this thesis regarding text. The results of the thesis are that there is an underrepresentation of witnesses, clowns and victims in the texts and an overrepresentation of people with authority like polices. The clowns are represented as evil and horrifying while the polices are shown as trustworthy and honest people.
|
215 |
Aproximação tempo de relaxação: Modelos alternativos em teoria cinética clássica / Relaxation time approach: alternative models in classical kinectic theoryOliveira, Diego Sales de 07 June 2013 (has links)
As possíveis soluções da equação integro-diferencial de Boltzmann constituem uma importante ferramenta para o estudo de gases e plasmas. No entanto, suas soluções analíticas são difíceis de serem encontradas. Uma abordagem bastante utilizada na literatura para obter soluções aproximadas da equação de Boltzmann é através de hipóteses que simplificam a forma da integral de colisão. Nesta dissertação, discutimos dois modelos colisionais alternativos que generalizam o método originalmente proposto por Bhatnagar, Gross e Krook, usualmente referido na literatura como aproximação BGK. O primeiro deles é um modelo de relaxação de segunda ordem, no qual introduzimos um segundo tempo de relaxação, 2 , relacionado com efeitos não lineares. O segundo modelo é baseado em outra generalização do modelo BGK obtida através de uma lei de potência parametrizada por um índice . No limite 1 o modelo BGK padrão é recuperado. As duas aproximações são fisicamente interpretadas. Além disso, para ilustrar nossos resultados com algumas aplicações mais quantitativas, obtemos as expressões analíticas para diversos coeficientes de transporte, a saber: a condutividade térmica (), a viscosidade de cisalhamento () e a condutividade elétrica (). Em particular, no modelo de relaxação de segunda ordem, as correções dependem da razão 1/2, onde 1 é a escala de tempo característica do modelo BGK padrão e 2 a nova escala de tempo associada aos efeitos não lineares. Finalmente, como um resultado geral, mostramos também que todas as correções nos coeficientes de transporte dependem numa certa potência do chamado número de Knudsen. / The possible solutions of the integro-diferential Boltzmann equation constitute an important tool for studying gases and plasmas. |However, its analytical solutions are hardly derived. An approach often adopted in the literature for obtaining approximate solutions of the Boltzmann equation is to consider some simplifying hypothesis on the collisional term. In this Dissertation, we discuss two diferent alternative collisional models which generalize the method originally proposed by Bhatnagar, Gross e Krook, and usually referred to as BGK approximation. The first one is a second order relaxation model in which a second relaxation time, 2, related with the nonlinear efects, is introduced. The second one is based on a diferent generalization of the BGK model which is obtained through a power law parameterized by a index . In the limit 1, the BGK model is recovered. Both approximations are physically interpreted. Further, in order to illustrate our results with some more quantitative applications, we derive the analytical expressions for several transport coefficients, among them the thermal conductivity (), the shear viscosity () and the electric conductivity (). In particular, for the second order relaxation model, we find that the corrections depend on the ratio 1/2 where 1 is the characteristic time scale of the BGK model and 2 describe the nonlinear efects. Finally, as a general result, it is also shown that all the corrections on the transport coefficients depend on a given power of the so-called Knudsen number.
|
216 |
As facetas do conhecimento físico e um modelo: a luz e a matéria / The Facets of Physical Knowledge and a Model: the Light and the MatterKneubil, Fabiana Botelho 31 March 2006 (has links)
Discutimos, nesse trabalho, aspectos das dimensões fenomenológica e teórica do conhecimento físico e o papel dos modelos como ponte unificadora dessas duas facetas do conhecimento. No âmbito do ensino, percebemos que as teorias ensinadas são muito pouco relacionadas aos fenômenos que permeiam o cotidiano dos alunos. Por isso, enfatizamos a importância do uso de modelos como instrumentos capazes de promover uma ligação entre o mundo abstrato, representado pelas teorias e o mundo palpável, representado pelos fenômenos. Discutimos, também, essas dimensões separadamente, com o propósito de ressaltar que muitas das dificuldades do ensino de física têm origem na epistemologia. Com o objetivo de dar realidade à infinidade de nuances que o conhecimento físico contempla, na segunda parte desse trabalho, confeccionamos um texto abordando a interação de ondas eletromagnéticas com a matéria, voltado para estudantes de graduação. Esse tema foi explorado com o auxílio de um modelo, chamado modelo de Drude, no qual a teoria do eletromagnetismo, representada pelas equações de Maxwell, é adaptada às características de um metal. Nesse texto didático procuramos explicitar, da maneira mais clara possível, as ligações entre idéias físicas e o mundo real, de modo a possibilitar que os estudantes venham a ter uma relação mais nova, rica e bonita com a física. / In this work we discuss both phenomenological and theoretical aspects of knowledge in Physics and the role of models as bridges between them. As far as teaching is concerned, we remark that the theories taught to students normally bear very little relation with phenomena in dayly life. Therefore we emphasize the need of using models as tools in order to promote meaningful links between the abstract world represented by theories and the real world, represented by phenomena. We discuss separately each of these dimensions, with the purpose of stressing that many of the difficulties in teaching Physics have their origin in epistemology. In the second part of this work we produce a pedagogical text dealing with the interaction between electromagnetic waves and matter, in order to realize the many faces that physical knowledge may have. This subject was approached with the help a model, known as Drude model, in which electromagnetic theory, represented by Maxwell equations, is adapted to the features of a metal. In this text we have tried to make explicit, as clearly as possible, the links between physical ideas and the real world, so that students may develop a new, rich and beautiful relationship with Physics.
|
217 |
Multiscale investigation of caking phenomenon of lactose powders : from physico-chemical aspects to industrial applications / Étude multi-échelles du phénomène de mottage des poudres du lactose : de la physico-chimie des matériaux aux applications industriellesAfrassiabian, Zahra 13 March 2019 (has links)
Cette thèse porte sur le problème fondamental du mottage des poudres suite aux mécanismes de transition de phase. Le projet vise à étudier l'impact des facteurs intrinsèques (structure moléculaire des matériaux, propriétés physiques et/ou physicochimiques, etc.) ou des facteurs environnementaux (conditions de stockage ou paramètres de procédé) sur la stabilité de la structure des poudres. Plus précisément, notre étude a mis en évidence le rôle prépondérant du phénomène de cristallisation et des transitions entre les différents polymorphes du lactose. L'accent a été mis sur le rôle des phénomènes de cristallisation et de la transition de phase dans l'apparition du mottage des poudres de lactose. Deux cas ont particulièrement retenu notre attention: (1) des poudres de lactose monohydrate contenant une fraction de particules amorphes et (2) des échantillons de poudre anhydre composés des anomères α et β du lactose. Dans les deux cas, le mottage a été induite par l'exposition des échantillons à l'air humide, soit dans un dispositif de sorption dynamique de vapeur (SPS), soit par des tests accélérés utilisant deux appareils conçus et réalisés dans notre laboratoire (CLAIR & OLAF). Nos résultats ont montré que, dans les deux cas, la principale cause de prise en masse était la formation de lactose monohydrate, qui est la forme la plus stable parmi tous les polymorphes de lactose. Cependant, les mécanismes élémentaires, les étapes limites et la cinétique du processus de transformation étaient différents dans chaque cas. Les paramètres les plus déterminants étaient l’humidité relative et la température alors que la pression n’a pas eu d’effet significatif. La résistance mécanique des échantillons mottés était étroitement liée au taux et à la cinétique de cristallisation. Enfin, des simulations numériques basées sur la méthode des éléments discrets (DEM) de la résistance mécanique des échantillons mottés ont été réalisées. Le modèle permet de décrire le comportement des échantillons mottés soumis à des contraintes mécaniques de compression ou de traction. / This PhD study focuses on the fundamental problem of powder caking due to phase transition mechanisms. The project aims to study the impact of intrinsic factors (molecular structure of materials, physical and/or physicochemical properties, etc.) or environmental factors (storage conditions or process parameters) on the stability of the structure of powders. More precisely, our study has highlighted the preponderant role of the crystallization phenomenon and the transitions taking place between the different polymorphs of lactose. Emphasis was placed on the role of crystallization phenomena and phase transition on the advent of lactose powder caking. Two cases attracted particular attention: (1) lactose monohydrate powders containing a fraction of amorphous particles and (2) anhydrous powder samples composed of ð and anomers of lactose. In both cases, the caking was induced by exposure of the samples to moist air, either in a Dynamic Vapor Sorption device (SPS) or in accelerated caking tests using two home-made equipment (CLAIR & OLAF). Our results showed that in both cases, the main cause of caking was the formation of lactose monohydrate, which is the most stable form among all lactose polymorphs. However, the elementary mechanisms, the limiting steps and the kinetics of the transformation process were different in each case. The more influencing parameters were the relative humidity and the temperature whereas the pressure has no significant effect. The yield stress of caked samples was closely linked with crystallization extent and kinetics. Finally, numerical simulations based on Discrete Element Method (DEM) of mechanical resistance of caked samples were performed using the "beam model". The model allows describing the behavior of the caked samples subjected to compressive or tractive mechanical stresses.
|
218 |
Aproximação tempo de relaxação: Modelos alternativos em teoria cinética clássica / Relaxation time approach: alternative models in classical kinectic theoryDiego Sales de Oliveira 07 June 2013 (has links)
As possíveis soluções da equação integro-diferencial de Boltzmann constituem uma importante ferramenta para o estudo de gases e plasmas. No entanto, suas soluções analíticas são difíceis de serem encontradas. Uma abordagem bastante utilizada na literatura para obter soluções aproximadas da equação de Boltzmann é através de hipóteses que simplificam a forma da integral de colisão. Nesta dissertação, discutimos dois modelos colisionais alternativos que generalizam o método originalmente proposto por Bhatnagar, Gross e Krook, usualmente referido na literatura como aproximação BGK. O primeiro deles é um modelo de relaxação de segunda ordem, no qual introduzimos um segundo tempo de relaxação, 2 , relacionado com efeitos não lineares. O segundo modelo é baseado em outra generalização do modelo BGK obtida através de uma lei de potência parametrizada por um índice . No limite 1 o modelo BGK padrão é recuperado. As duas aproximações são fisicamente interpretadas. Além disso, para ilustrar nossos resultados com algumas aplicações mais quantitativas, obtemos as expressões analíticas para diversos coeficientes de transporte, a saber: a condutividade térmica (), a viscosidade de cisalhamento () e a condutividade elétrica (). Em particular, no modelo de relaxação de segunda ordem, as correções dependem da razão 1/2, onde 1 é a escala de tempo característica do modelo BGK padrão e 2 a nova escala de tempo associada aos efeitos não lineares. Finalmente, como um resultado geral, mostramos também que todas as correções nos coeficientes de transporte dependem numa certa potência do chamado número de Knudsen. / The possible solutions of the integro-diferential Boltzmann equation constitute an important tool for studying gases and plasmas. |However, its analytical solutions are hardly derived. An approach often adopted in the literature for obtaining approximate solutions of the Boltzmann equation is to consider some simplifying hypothesis on the collisional term. In this Dissertation, we discuss two diferent alternative collisional models which generalize the method originally proposed by Bhatnagar, Gross e Krook, and usually referred to as BGK approximation. The first one is a second order relaxation model in which a second relaxation time, 2, related with the nonlinear efects, is introduced. The second one is based on a diferent generalization of the BGK model which is obtained through a power law parameterized by a index . In the limit 1, the BGK model is recovered. Both approximations are physically interpreted. Further, in order to illustrate our results with some more quantitative applications, we derive the analytical expressions for several transport coefficients, among them the thermal conductivity (), the shear viscosity () and the electric conductivity (). In particular, for the second order relaxation model, we find that the corrections depend on the ratio 1/2 where 1 is the characteristic time scale of the BGK model and 2 describe the nonlinear efects. Finally, as a general result, it is also shown that all the corrections on the transport coefficients depend on a given power of the so-called Knudsen number.
|
219 |
As facetas do conhecimento físico e um modelo: a luz e a matéria / The Facets of Physical Knowledge and a Model: the Light and the MatterFabiana Botelho Kneubil 31 March 2006 (has links)
Discutimos, nesse trabalho, aspectos das dimensões fenomenológica e teórica do conhecimento físico e o papel dos modelos como ponte unificadora dessas duas facetas do conhecimento. No âmbito do ensino, percebemos que as teorias ensinadas são muito pouco relacionadas aos fenômenos que permeiam o cotidiano dos alunos. Por isso, enfatizamos a importância do uso de modelos como instrumentos capazes de promover uma ligação entre o mundo abstrato, representado pelas teorias e o mundo palpável, representado pelos fenômenos. Discutimos, também, essas dimensões separadamente, com o propósito de ressaltar que muitas das dificuldades do ensino de física têm origem na epistemologia. Com o objetivo de dar realidade à infinidade de nuances que o conhecimento físico contempla, na segunda parte desse trabalho, confeccionamos um texto abordando a interação de ondas eletromagnéticas com a matéria, voltado para estudantes de graduação. Esse tema foi explorado com o auxílio de um modelo, chamado modelo de Drude, no qual a teoria do eletromagnetismo, representada pelas equações de Maxwell, é adaptada às características de um metal. Nesse texto didático procuramos explicitar, da maneira mais clara possível, as ligações entre idéias físicas e o mundo real, de modo a possibilitar que os estudantes venham a ter uma relação mais nova, rica e bonita com a física. / In this work we discuss both phenomenological and theoretical aspects of knowledge in Physics and the role of models as bridges between them. As far as teaching is concerned, we remark that the theories taught to students normally bear very little relation with phenomena in dayly life. Therefore we emphasize the need of using models as tools in order to promote meaningful links between the abstract world represented by theories and the real world, represented by phenomena. We discuss separately each of these dimensions, with the purpose of stressing that many of the difficulties in teaching Physics have their origin in epistemology. In the second part of this work we produce a pedagogical text dealing with the interaction between electromagnetic waves and matter, in order to realize the many faces that physical knowledge may have. This subject was approached with the help a model, known as Drude model, in which electromagnetic theory, represented by Maxwell equations, is adapted to the features of a metal. In this text we have tried to make explicit, as clearly as possible, the links between physical ideas and the real world, so that students may develop a new, rich and beautiful relationship with Physics.
|
220 |
Modelos de mapas simpléticos para o movimento de deriva elétrica com efeitos de raio de Larmor finito / Area-Preserving Maps Models of the Electric Drift Motion with Finite Larmor Radius EffectsFonseca, Júlio César David da 10 May 2016 (has links)
Mapas simpléticos têm sido amplamente utilizados para modelar o transporte caótico em plasmas e fluidos. Neste trabalho, propomos três tipos de mapas simpléticos que descrevem o movimento de deriva elétrica em plasmas magnetizados. Efeitos de raio de Larmor finito são incluídos em cada um dos mapas. No limite do raio de Larmor tendendo a zero, o mapa com frequência monotônica se reduz ao mapa de Chirikov-Taylor, e, nos casos com frequência não-monotônica, os mapas se reduzem ao mapa padrão não-twist. Mostramos como o raio de Larmor finito pode levar à supressão de caos, modificar a topologia do espaço de fases e a robustez de barreiras de transporte. Um método baseado na contagem dos tempos de recorrência é proposto para analisar a influência do raio de Larmor sobre os parâmetros críticos que definem a quebra de barreiras de transporte. Também estudamos um modelo para um sistema de partículas onde a deriva elétrica é descrita pelo mapa de frequência monotônica, e o raio de Larmor é uma variável aleatória que assume valores específicos para cada partícula do sistema. A função densidade de probabilidade para o raio de Larmor é obtida a partir da distribuição de Maxwell-Boltzmann, que caracteriza plasmas na condição de equilíbrio térmico. Um importante parâmetro neste modelo é a variável aleatória gama, definida pelo valor da função de Bessel de ordem zero avaliada no raio de Larmor da partícula. Resultados analíticos e numéricos descrevendo as principais propriedades estatísticas do parâmetro gama são apresentados. Tais resultados são então aplicados no estudo de duas medidas de transporte: a taxa de escape e a taxa de aprisionamento por ilhas de período um. / Area-preserving maps have been extensively used to model chaotic transport in plasmas and fluids. In this work we propose three types of maps describing electric drift motion in magnetized plasmas. Finite Larmor radius effects are included in all maps. In the limit of zero Larmor radius, the monotonic frequency map reduces to the Chirikov-Taylor map, and, in cases with non-monotonic frequencies, the maps reduce to the standard nontwist map. We show how the finite Larmor radius can lead to chaos suppression, modify the phase space topology and the robustness of transport barriers. A method based on counting the number of recurrence times is used to quantify the dependence on the Larmor radius of the threshold for the breakup of transport barriers. We also study a model for a system of particles where the electric drift is described by the monotonic frequency map, and the Larmor radius is a random variable that takes a specific value for each particle of the system. The Larmor radius\' probability density function is obtained from the Maxwell-Boltzmann distribution, which characterizes plasmas in thermal equilibrium. An important parameter in this model is the random variable gamma, defined by the zero-order Bessel function evaluated at the Larmor radius\'particle. We show analytical and numerical computations related to the statistics of gamma. The set of analytical results obtained here is then applied to the study of two numerical transport measures: the escape rate and the rate of trapping by period-one islands.
|
Page generated in 0.1144 seconds