La modélisation des événements et de leurs propriétés temporelles concerne des types variés d’utilisateurs et de communautés scientifiques. Nous nous plaçons dans le cadre du paradigme Objet et construisons un méta modèle opérationnel servant de représentation pivot, indépendante du métier pour représenter des événements composites avec leurs propriétés structurelles et temporelles. Le méta modèle PTOM (Periodic Temporal Occurrence Metamodel) prend en compte l’expression de contraintes structurelles sur les événements, ou géométriques, topologiques et relationnelles sur la temporalité de leurs occurrences. Il privilégie la représentation en intension (vs extension) des occurrences d’événements périodiques. PTOM étend la norme ISO 19108 et s’adapte aux standards EventsML G2 et iCalendar. Sur un plan théorique, nous étendons les algèbres d’intervalles d’ALLEN et de LIGOZAT, et proposons un système de relations topologiques entre intervalles non convexes (ALLEN*) dont nous étudions les propriétés. Ces résultats sont intégrés dans PTOM. La première application de PTOM est la spécification de la sémantique du calendrier grégorien. Les éléments calendaires sont réintroduits en tant qu’événements périodiques dans PTOM, ce qui renforce son pouvoir expressif. PTOM a été mis en œuvre lors d’un projet ANR sur des corpus d’événements journalistiques (agences de presse) concernant les loisirs et la culture. L’Ingénierie Dirigée par les Modèles a été utilisée pour la conception et l’exploitation de PTOM. Cela permet de gérer la complexité, d’assurer la maintenabilité et la cohérence de l’ensemble et enfin, de générer automatiquement des interfaces pour les pourvoyeurs ou utilisateurs de données. / Modelling events with their temporal properties concerns many users and scientific communities. We adopted the Object paradigm and designed an operational metamodel which stands as a pivot business independent representation for composite events accompanied with their structural and temporal properties. PTOM metamodel (Periodic Temporal Occurrence Metamodel) accounts for structural constraints upon events and geometric, topologic or relational constraints upon their temporal occurrences. It gives prominence to intensional representations of periodic events occurrences vs extensional ones. PTOM extends ISO 19108 standard and fits EventsML G2 and iCalendar. From a theoretical viewpoint, we extend ALLEN’s and LIGOZAT’s interval algebras and propose a special set of topological relations between non convexintervals (ALLEN*), and study its properties. These results are part of PTOM. The first application of PTOM results in a specification of the Gregorian calendar semantics. Calendar elements are reinserted as periodic events in PTOM thus enhancing its expressiveness. PTOM was also experimented upon a corpus of journalistic (press agencies) events dedicated to leisure and culture at the occasion of an ANR project. Model Driven Engineering was extensively used for PTOM design and use.It allows to manage complexity and to ensure maintainability, consistency and eventually can automatically generate data provider or end user interfaces as well.

Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-05-05T14:21:03Z No. of bitstreams: 1 2012 - Cleide Domingues Coelho.pdf: 19229976 bytes, checksum: 94c069047adceba0bbb1974c338db08e (MD5) / Made available in DSpace on 2017-05-05T14:21:03Z (GMT). No. of bitstreams: 1 2012 - Cleide Domingues Coelho.pdf: 19229976 bytes, checksum: 94c069047adceba0bbb1974c338db08e (MD5) Previous issue date: 2012-02-28 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Parasites can affect the physical condition, survival and reproduction of birds may be an important factor in the life history of the host, exerting strong pressure ecological and evolutionary. Among the most important parasites affecting passerine birds, Isospora species were included, and the oocysts counts were used for estimating infection in wild birds as well as essential for studies of prevalence, diagnosis and control of coccidiosis in birds from seizures of wild animals, and keeping under quarantine at Wild Animal Sorting Center and latter for the release. This study aimed to determine the circadian rhythm or periodicity in the elimination of oocysts of Isospora species in Passeriformes, and identify the species of parasite found and verify the effectiveness and prophylaxis of anticoccidial drugs during the quarantine period. In a total of 1393 fecal samples were collected from birds of the order Passeriformes belonging to different families and species, from the apprehensions of wild animals and sent to CETAS (Wild Animal Sorting Center)/IBAMA at Municipality of Serop?dica in the State of Rio de Janeiro. After a period of sporulation, the samples were subjected to centrifugal flotation technique with sucrose, quantified and the results expressed in OoPD (oocysts per defecation). The results showed that, regardless of the continent where the birds live, photoperiod is an important factor in maintaining the schedule for the elimination of oocysts of the genus Isospora. Birds of several families had an OoPD means, in relationship of shedding oocysts in the feces, the highest eliminations is in the afternoon. For control of coccidiosis in these birds, throughout the use of anticoccidial drugs were observed that the effectiveness may vary with the species of the parasite and the birds, because they have different feeding habits and behavior, which may influence the response to treatment / Os parasitos podem afetar a condi??o f?sica, sobreviv?ncia e reprodu??o das aves, podendo ser um importante fator na hist?ria de vida do hospedeiro, exercendo forte press?o ecol?gica e evolucion?ria. Dentre os parasitos mais importantes que afetam os Passeriformes podemos citar os cocc?dios do g?nero Isospora, e a estimativa da infec??o em p?ssaros silvestres ? essencial para os estudos de preval?ncia, diagn?stico e controle deste cocc?dio nas aves oriundas de apreens?es do tr?fico de animais silvestres, encaminhadas e mantidas sob regime de quarentena nos centros de triagem de animais silvestres e destinadas ? soltura. Este trabalho teve por objetivo, determinar o ritmo circadiano ou periodicidade na elimina??o de oocistos de Isospora spp. em Passeriformes, assim como identificar as esp?cies do parasito encontradas e verificar a efic?cia dos anticocc?dios na profilaxia durante o per?odo de quarentena. Foram coletadas 1393 amostras fecais de aves da ordem Passeriformes pertencentes ? diversas fam?lias e esp?cies, oriundas da apreens?es do tr?fico de animais silvestres e encaminhadas ao CETAS/IBAMA, Serop?dica, RJ. Ap?s um per?odo de esporula??o, as amostras foram submetidas a t?cnica de centr?fugo-flutua??o com sacarose, quantificadas e os resultados expressos em OoPD (oocistos por defeca??o). Os resultados demonstraram que independentemente do continente onde as aves habitam, o fotoper?odo ? um fator importante na manuten??o da periodicidade da elimina??o dos oocistos de Isospora spp. e os Passeriformes de diversas fam?lias apresentaram um valor m?dio de OoPD mais elevado no per?odo da tarde. Foi verificado o controle da coccidiose nestes p?ssaros atrav?s do uso de anticocc?dios e observou-se que a efic?cia pode variar de acordo com a esp?cie do parasito e dos p?ssaros, os quais apresentam h?bitos comportamentais e alimentares diversificados que podem influenciar na resposta ao tratamento.

In this paper I introduce some background for subtraction games and explore the Sprague-Grundy functions defined on them. I exhibit some subtraction games where the functions are guaranteed to be strictly periodic. I also exhibit a class of subtraction games which have bounded range, and show there are uncountably many of these.

L'objet central de l'étude est la modélisation mathématique de phénomènes périodiques dans l'enseignement secondaire, plus particulièrement celle des phénomènes périodiques temporels. L'étude part d'un constat établi en comparant les enseignements secondaires français et vietnamien : soit on évite l'enseignement de la modélisation mathématique en concevant le rapport des mathématiques aux autres disciplines scientifiques comme un rapport d'application (Viêt Nam), soit on préconise la prise en compte de la modélisation mathématique sans donner les moyens aux enseignants de mathématiques de l'enseigner (France). La périodicité est le concept central dans le processus de modélisation des phénomènes cycliques et des phénomènes oscillatoires. Dans la genèse scientifique de ce concept, les fonctions périodiques, notamment les fonctions trigonométriques, se sont constituées progressivement comme modèles de grandeurs variables en général en fonction du temps, qui retournent régulièrement et indéfiniment au même état. A partir d'une enquête épistémologique sur les phénomènes périodiques temporels étudiés par la Physique, nous repérons deux modèles mathématiques, C (mouvements circulaires uniformes) et O (oscillations harmoniques) avec leurs différents registres, graphique et algébrique. Une analyse institutionnelle examine et compare la présence de ces deux modèles dans les enseignements secondaires de mathématiques et de physique, en France et au Viêt Nam. Cette analyse met en évidence la faiblesse de l'articulation entre ces deux modèles et l'absence de technique pour effectuer le passage de l'un des modèles à l'autre, alors qu'il s'agit d'un des enjeux de la modélisation elle-même. Le dispositif expérimental se compose d'un questionnaire aux élèves vietnamiens et d'une ingénierie didactique qui organise, dans un environnement de géométrie dynamique et en articulant les deux modèles C et O, la construction de fonctions périodiques comme modèles de phénomènes de co-variations périodiques. / The focus of the study is mathematical modeling of periodic phenomena in secondary education, particularly that of temporal periodic phenomena. The study starts from an observation by comparing the French and Vietnamese secondary education: either they avoid the teaching of mathematical modeling in designing the relationship of mathematics to other scientific disciplines as an applicable connection (Vietnam) or they advocate the consideration of mathematical modeling without empower mathematics teachers to teach it (France). The periodicity is the central concept in the modeling process of cyclical and oscillatory phenomena. In the scientific genesis of this concept, the periodic functions especially trigonometric functions, was established gradually as models of variable quantities which return regularly and indefinitely in the same state over time. From an epistemological investigation of the temporal periodic phenomena studied by physics, we identify two mathematical models, C (uniform circular movement) and O (harmonic oscillations) with their different registers, graphic and algebraic. Institutional analysis examines and compares the presence of these two models in secondary education of mathematics and physics in France and Vietnam. This analysis shows the weakness of the articulation between these two models and the absence of technique to make the transition from one model to another which is one of the stakes of modeling itself. The experimental way consists of a questionnaire to Vietnamese pupils and a didactical engineering that organizes in a dynamic geometrical environment by articulating both models C and O, for the construction of periodic functions as models of phenomena of periodic co-variations.

[pt] Nesta dissertação utilizamos um modelo baseado na teoria de fenômenos críticos para explicar a formação de preços de ativos financeiros no período précrash. A evolução dos preços é descrita por um crescimento lento em forma de lei de potência, superposto a oscilações periódicas em escala logarítmica, sendo denominado modelo log-periódico. Este crescimento é eventualmente interrompido por um colapso dos preços que ocorre em um curto e crítico intervalo de tempo.O objetivo deste trabalho é o de investigar o modelo logperiódico do ponto de vista econométrico, criticando e propondo melhoramentos na sua especificação de forma que as inferências estatísticas dos seus parâmetros sejam mais confiáveis. Baseado nesta análise é proposta uma extensão do modelo log-periódico, com a incorporação de estrutura auto- regressiva e heterocedástica condicional no termo aleatório do modelo original. O modelo é aplicado a índices de diversos mercados mundiais, a saber: HANG SENG (Hong Kong), NASDAQ (EUA), IBOVESPA (Brasil), MERVAL (Argentina), INDIA BSE NATIONAL (Índia) e FTSE100 (Grã-Bretanha). Os nossos resultados indicam que a utilização destes modelos na prática requer alguma cautela uma vez que a sua base inferencial é frágil. / [en] In this work we employ a model based on the critical phenomena theory to explain the asset price formation associated to the pre- crash period. The evolution of the price is given by an over-all power law acceleration decorated by oscillations called log-periodic model. This growth is likely to be interrupted by a crash of prices that happen in a short and critical time interval. The purpose of this work is to investigate the log-periodic model within the econometric approach by suggesting guidelines to achieve its performance in order to accomplish reliable statistical inferences. Based on this analysis we here propose a stretching of the log-periodic model through the introduction of an autoregressive structure and an autoregressive conditional heteroskedasticity at the residual of the original model. The current model is applied to the study of financial index of the stock markets worldwide as: HANG SENG (Hong Kong), NASDAQ (USA), IBOVESPA (Brazil), MERVAL (Argentina), INDIA BSE NATIONAL (India) and FTSE100 (United Kingdom). The output of such work indicates that the use of the logperiodic model requires some care as far as its inference basis is fragile.

Threshold dynamics used to control the spread of the disease in infectious disease phenomena has an overwhelming importance and interest in mathematical epidemiology. One of the famous threshold quantity is known to be the basic reproduction ratio. Its formulation as well as computation is the main concern of infectious diseases. The aim of this thesis is to analyze the basic reproduction ratio in both autonomous and periodic systems via defining R0 as the spectral radius of the next generation operator. This thesis presents the vector host model for the diseases Dengue fever and avian influenza. As emerging of the diseases shows periodicity, systems of periodic ordinary differential equations are considered for both types of diseases. Simple implementation of the time-averaged systems gives rise to the comparison of these with the periodic systems. Thus, we investigate the occurence of the existence of underestimation or overestimation of the basic reproduction ratio in timeaveraged systems.

Population dynamics is the dominant branch of mathematical biology. The first model for population dynamics was developed by Thomas Malthus. A more complicated model was developed by Pierre Fran&ccedil / ois Verhulst and it is called the logistic equation. Our aim in this thesis is to extend the models using piecewise constant arguments and to find the conditions when the models have fixed points, periodic solutions and chaos with investigation of stability of periodic solutions.

Pulsars, as rotating magnetised neutron stars got much attention during the last 40 years since their discovery. Observations revealed them to be gamma-ray emitters with energies continuing up to the sub 100 GeV region. Better observation of this upper energy cut-off region will serve to enhance our theoretical understanding of pulsars and neutron stars. The H-test has been used the most extensively in the latest periodicity searches, whereas other tests have limited applications and are unsuited for pulsar searches. If the probability distribution of a test statistic is not accurately known, it is possible that, after searching through many trials, a probability for uniformity can be given, which is much smaller than the real value, possibly leading to false detections. The problem with the H-test is that one must obtain the distribution by simulation and cannot do so analytically. For such simulations, random numbers are needed and are usually obtained by utilising so-called pseudo-random number generators, which are not truly random. This immediately renders such generators as useless for the simulation of the distribution of the H-test. Alternatively there exists hardware random number generators, but such devices, apart from always being slow, are also expensive, large and most still don't exhibit the true random nature required. This was the motivation behind the development of a hardware random number generator which provides truly random U(0,l) numbers at very high speed and at low cost The development of and results obtained by such a generator are discussed. The device delivered statistically truly random numbers and was already used in a small simulation of the H-test distribution. / Thesis (M.Sc. (Physics))--North-West University, Potchefstroom Campus, 2005.

Pulsars, as rotating magnetised neutron stars got much attention during the last 40 years since their discovery. Observations revealed them to be gamma-ray emitters with energies continuing up to the sub 100 GeV region. Better observation of this upper energy cut-off region will serve to enhance our theoretical understanding of pulsars and neutron stars. The H-test has been used the most extensively in the latest periodicity searches, whereas other tests have limited applications and are unsuited for pulsar searches. If the probability distribution of a test statistic is not accurately known, it is possible that, after searching through many trials, a probability for uniformity can be given, which is much smaller than the real value, possibly leading to false detections. The problem with the H-test is that one must obtain the distribution by simulation and cannot do so analytically. For such simulations, random numbers are needed and are usually obtained by utilising so-called pseudo-random number generators, which are not truly random. This immediately renders such generators as useless for the simulation of the distribution of the H-test. Alternatively there exists hardware random number generators, but such devices, apart from always being slow, are also expensive, large and most still don't exhibit the true random nature required. This was the motivation behind the development of a hardware random number generator which provides truly random U(0,l) numbers at very high speed and at low cost The development of and results obtained by such a generator are discussed. The device delivered statistically truly random numbers and was already used in a small simulation of the H-test distribution. / Thesis (M.Sc. (Physics))--North-West University, Potchefstroom Campus, 2005.

This study investigated several, previously little-known, aspects of reproductive physiology and endocrinology in the substrate-spawning cÌchlid Tilapia zillii; a tilapia that is becoming increasingly popular in world aquaculture. Studies were undertaken in controlled laboratory aquaria, thereby reducing the potential influence of environmental variation evident in many previous field studies of this species. Analysis involved two strains of T. zillii: strain 'A' (T. zillii) and strain 'B' (formerly known as Tilapia tholloni). Spawning periodicity and total fecundity generally increased with fish size. Egg size varied within a narrow window and did not generally increase with fish size though fish weighing 100 - 200g tended to produce the largest eggs. The best estimate of spawning periodicity was considered to be 'mean days elapsed/spawn' as this figure was based upon both spawning and non-spawning fish in an experimental group. Mean days elapsed/spawn increased with increasing fish size and averaged 61.4 days and 37.5 days in strains 'A' and 'B' respectively. The shortest reproductive cycles observed were just 7 days and 6 days for strains 'A' and 'B' respectively. Total fecundity ranged from 461 - 11640 eggs/clutch. Mean total fecundity was 3606+/-280 in strain 'A' and 3560+/-243 in strain 'B'. Mean egg diameter was 1.5+/-0.04mm and 1.4+/-0.08mm in strains 'A' and 'B' respectively. Fecundity and egg size also varied over successive spawns in serial-spawning females but these variations did not appear to be related to spawning periodicity. Regression analysis revealed strong relationships between fish size (weight and length) and total fecundity, relative fecundity and total egg volume. Relationships between fish size and egg size were generally much weaker. Fecundity and egg size were related to the length of the preceding inter-spawn-interval (ISI) in fish of certain weight categories but not others, providing limited evidence that length of ISI may in par, control fecundity and egg size in this species. Ovarian recrudescence was classified into ten distinct developmental stages based upon oocyte size, biochemical properties and structure. This classification scheme was comparable to classification schemes developed for other teleosts but represents the first detailed description of oocyte growth in a substrate-spawning tilapia. Radioimmunoassay and stereological analysis provided valuable and novel data concerning the dynamics of ovarian development in this species. Levels of 17ßoestradiol (E2) and testosterone (T) peaked within 6 days of spawning, suggesting that vitellogenesis began as early as day 2 or 3 post-spawning. By day 8, ovaries were dominated by large late-vitellogenic/maturing oocytes (stages 6 & 7) occupying 60 - 70% of the ovary. Gonadosomatic index (GSI) reached maximal levels by day 14. Since the proportion of stage 6/7 oocytes exhibited little change from day 8 onwards, it is suggested that pre-vitellogenic oocytes are recruited into vitellogenic growth immediately after spawning and complete vitellogenesis as early as day 8 postspawning. Analysis of serial-spawning fish found that initial post-spawn E2 and T peaks (on days 2 - 6) were much lower after the second spawning. Sex steroid levels were also found to be suppressed in confined T. zillii (i.e. where stocking densities were > lOkg/m3). Confined females failed to spawn but displayed a marked tendency to do so after transfer to individual aquaria. Serum E2 and T were suppressed during confinement but increased rapidly following transfer to individual aquaria (coincident with resumed spawning activity). It is suggested that levels of E2 and T under confinement are not sufficient to allow completion of vitellogenic growth and are most probably suppressed via a pheromonal mechanism. Finally, the present study investigated the effect of prolonged food restriction on various aspects of reproduction. T. zillii were rationed from first feeding and throughout the following 17 months. Despite very large differences in fish size, no significant differences were detected in total fecundity, egg diameter nor total egg volume once data had been adjusted for differences in fish size. These data suggest that despite very large differences in food availability throughout the periods of sexual differentiation and on-growing, investment in reproduction remained relatively consistent. It appeared that during food restriction, T. zillii sacrificed body weight and growth so as to maintain reproductive investment. In summary, this study provides valuable and novel information regarding the reproductive physiology and endocrinology of female T. zillii and suggests that this species may be a suitable 'model' species for future work on fecundity and ovarian development.