In recent years, the rapid development of economy and industry in Xiamen Bay causes serious environmental problems, particularly poor air quality and visibility impairment. There are no large-scale industrial emission sources in Kinmen Island, however, its ambient air quality is always the poorest in Taiwan. Moreover, ambient air quality monitoring data showed that PM10 concentrations varied in daytime and at nighttime. Consequently, this study tired to ascertain the potential causes for this phenomenon. This study selected ten particulate matter (PM) sampling sites at Xiamen Bay, including five sites at Kinmen Island and five sites at metro Xiamen. Particulate matter sampling was conducted in daytime (8:00-17:00) and at nighttime (17:00-8:00), which included regular and intensive sampling. Regular sampling was conducted to collect PM10 with high-volume samplers three times a month from April 2009 to April 2010, while intensive sampling was conducted to collect fine (PM2.5) and coarse (PM2.5-10) particles with dichotomous samplers and particle size distribution with a MOUDI at site B2 for consecutive 5 days in the spring and winter of 2009~2010. After sampling, the physicochemical properties of PM, including mass concentrations, particle size distribution, water- soluble ionic species, metallic elements, and carbonaceous contents were further analyzed. The level of atmospheric PM is affected by meteorological condition, thus PM10 concentrations in winter and fall was much higher than those in spring and summer. Results from backward trajectories showed that the concentrations of PM10 blown from the north were generally higher than those from the south. Furthermore, t-test analysis indicated that PM10 concentrations in daytime and at nighttime at site B3 were significantly different (p-value<0.05). During the intensive sampling periods, PM10 concentrations were mainly affected by coarse particles compared to fine particles. The highest concentration for fine and coarse particle modes occurred at the size ranges of 0.32~0.56 £gm and 3.2~5.6 £gm, respectively. The most abundant water-soluble ionic species of PM10 were secondary inorganic aerosols (SO42-, NO3-, and NH4+) which accounted for 85% of total ions. The daytime and nighttime PM10 concentration ratios (D/N) for Mg, K, Ca, Cr, Mn, Fe, Zn, Al, Cu, As, and V were in the same order of magnitude, however, the D/N ratios of Cd, Pb, Ni, and Ti in spring and summer varied higher than an order of magnitude, indicating that the emission sources of PM were different in daytime and at nighttime. Correlation analysis of OC and EC showed that OC and EC at nighttime had a higher correlation than those in daytime, while OC and EC had a higher correlation in Kinmen Island than those in metro Xiamen, indicating carbonaceous sources must be different in summer and winter at Xiamen Bay. Enrichment factor analysis revealed that ceramic industry, stone processing, and cement industry had higher correlation with PM10 concentration than utility power plants. Crustal dusts consisted of road dusts, farmland dusts, and constructive dusts, while biomass burning was not a negligible sources. Results obtained from PCA and CMB receptor modeling showed that major sources of PM in Xiamen Bay were secondary inorganic aerosols, fuel and biomass burning, marine aerosols, vehicular exhansts, and soil dusts. Besides, stone processing, cement industry, ceramic industry, and utility power plants had the highest contribution in winter. Their contributions in daytime and at nighttime were 38% and 45%, respectively.

This study examines two &lsquo / socialist&rsquo / utopias of the late 19th century: W. Morris&rsquo / s News from Nowhere and E. Bellamy&rsquo / s Looking Backward. The major concern is to question the validity of title &lsquo / socialist&rsquo / for these two texts. The reference points for such an analysis are: modernity, Marxism of the late 19th century and the practice of discipline. In this context, the intention is to find out ruptures and continuities with respect to the central ideas of socialism and basic premises of modernity. The study explorates that there are serious points of rupture in these two texts with respect to the major premises of modernity, because in Morris&rsquo / s utopia there is a romantic search for restoring communism of the 14th century, in Bellamy&rsquo / s text there are typical reactionary modernist suggestions concerning the nature of typical socialist societies. In that sense, due to the disassociation between socialism and modernity in these two texts, it is very problematic to classify these utopias as socialist. The study also questions whether the sources of such disassociation are embedded in Marxism itself. In response to such question, the study argues that this is the case to a great extent.

A wide range of additional forward chaining applications could be realized with deductive databases, if their rule formalism, their immediate consequence operator, and their fixpoint iteration process would be more flexible. Deductive databases normally represent knowledge using stratified Datalog programs with default negation. But many practical applications of forward chaining require an extensible set of user–defined built–in predicates. Moreover, they often need function symbols for building complex data structures, and the stratified fixpoint iteration has to be extended by aggregation operations. We present an new language Datalog*, which extends Datalog by stratified meta–predicates (including default negation), function symbols, and user–defined built–in predicates, which are implemented and evaluated top–down in Prolog. All predicates are subject to the same backtracking mechanism. The bottom–up fixpoint iteration can aggregate the derived facts after each iteration based on user–defined Prolog predicates.

Cette thèse présente de nouvelles méthodes d'extraction de " pistes" dans des images gisement- temps présentées aux opérateurs d'un système sonar passif. Les pistes gisement-temps extraites sont nécessaires à la fonction trajectographie qui se trouve en aval dans la chaîne de traitement de l'information d'un tel système. Les méthodes que nous proposons se fondent sur l'analyse statistique de ce type d'image issue du traitement d'antenne. Cette analyse est l'objet du second chapitre. Puis dans une première approche, on ne considère que le cas (irréaliste) où une seule piste au plus, est présente dans l'image. Les deux extracteurs que nous construisons à partir de l'arsenal des techniques associées aux chaînes de Markov cachées (HMM), tiennent compte de l'intermittence de cette piste. Une fois la piste extraite par l'une ou l'autre méthode, on lui associe un module de trajectographie qui permet d'évaluer les performances des extracteurs et montre que leurs sorties sont exploitables. La seconde partie de la thèse se focalise sur le cas réel c'est-à-dire la présence de plusieurs pistes intermittentes et pouvant se croiser dans l'image gisement-temps. Deux extracteurs sont présentés et étudiés: l'un effectuant une extraction séquentielle c'est-à-dire extrayant piste après piste, un autre appelé extracteur parallèle, effectuant une extraction de l'ensemble des pistes simultanément. Les deux extracteurs proposés gérant de façon très insatisfaisante le croisement de pistes, on leur associe un module de trajectographie qui permet d'améliorer sensiblement celui-ci. Un bilan global du couple (extraction, trajectographie) est présenté dans la dernière partie de cette thèse.

No description available.

An experimental study was undertaken to investigate the effect of roughness on the characteristics of separated and reattached turbulent shear flow downstream of a backward facing step. Particle image velocimetry technique was used to conducted refined velocity measurements over a reference smooth acrylic wall and rough walls produced from sandpaper 36 and 24 grits positioned downstream of a backward facing step, one after another. Each experiment was conducted at Reynolds number based on the step height and centerline mean velocity of 7050. The results showed that sandpaper 36 and 24 grits increased the reattachment length by 5% and 7%, respectively, compared with the value obtained over the smooth wall. The distributions of the mean velocities, Reynolds stresses, triple velocity correlations and turbulence production are used to examine roughness effects on the flow field downstream of the backward facing step. Two-point auto-correlation function and proper orthogonal decomposition (POD) are also used to investigate the impact of wall roughness on the large scale structures.

A robotically-controlled actuation system has been developed and built to perform active open-loop flow control experiments on transitional and turbulent backward-facing step flows in water. Control of the reattaching shear layer used hydraulic suction-and-blowing actuation emanating from 128 individual ports along the separation edge of the step. Each ports perturbation was periodic in time, but individually controlled to produce either spanwise-invariant (2D) or spanwise-varying (3D) spatial actuation profiles. An image processing system and special aqueous tuft were developed to measure the length of the recirculation bubble. Multiple images of a tuft array were time-averaged to do so. In general, 3D forcing was no more effective in reducing bubble length than 2D forcing. However, greater local spanwise reductions in reattachment length were observed for some cases of spanwise-varying forcing. Backlit dye was used to track the evolution of vorticity in the flow in video and still images.

Dans de nombreuses disciplines, les approches permettant d'étudier et de quantifier l'influence de données incertaines sont devenues une nécessité. Bien que la propagation directe d'incertitudes ait été largement étudiée, la propagation inverse d'incertitudes demeure un vaste sujet d'étude, sans méthode standardisée. Dans cette thèse, une nouvelle méthode de propagation inverse d'incertitude est présentée. Le but de cette méthode est de déterminer l'incertitude d'entrée à partir de données de sortie considérées comme incertaines. Parallèlement, les méthodes d'analyse de sensibilité sont également très utilisées pour déterminer l'influence des entrées sur la sortie lors d'un processus de modélisation. Ces approches permettent d'isoler les entrées les plus significatives, c'est à dire les plus influentes, qu'il est nécessaire de tester lors d'une analyse d'incertitudes. Dans ce travail, nous approfondirons tout d'abord la méthode d'analyse de sensibilité de Sobol, qui est l'une des méthodes d'analyse de sensibilité globale les plus efficaces. Cette méthode repose sur le calcul d'indices de sensibilité, appelés indices de Sobol, qui représentent l'effet des données d'entrées (vues comme des variables aléatoires continues) sur la sortie. Nous démontrerons ensuite que la méthode de Sobol donne des résultats fiables même lorsqu'elle est appliquée dans le cas discret. Puis, nous étendrons le cadre d'application de la méthode de Sobol afin de répondre à la problématique de propagation inverse d'incertitudes. Enfin, nous proposerons une nouvelle approche de la méthode de Sobol qui permet d'étudier la variation des indices de sensibilité par rapport à certains facteurs du modèle ou à certaines conditions expérimentales. Nous montrerons que les résultats obtenus lors de ces études permettent d'illustrer les différentes caractéristiques des données d'entrée. Pour conclure, nous exposerons comment ces résultats permettent d'indiquer les meilleures conditions expérimentales pour lesquelles l'estimation des paramètres peut être efficacement réalisée. / Approaches for studying uncertainty are of great necessity in all disciplines. While the forward propagation of uncertainty has been investigated extensively, the backward propagation is still under studied. In this thesis, a new method for backward propagation of uncertainty is presented. The aim of this method is to determine the input uncertainty starting from the given data of the uncertain output. In parallel, sensitivity analysis methods are also of great necessity in revealing the influence of the inputs on the output in any modeling process. This helps in revealing the most significant inputs to be carried in an uncertainty study. In this work, the Sobol sensitivity analysis method, which is one of the most efficient global sensitivity analysis methods, is considered and its application framework is developed. This method relies on the computation of sensitivity indexes, called Sobol indexes. These indexes give the effect of the inputs on the output. Usually inputs in Sobol method are considered to vary as continuous random variables in order to compute the corresponding indexes. In this work, the Sobol method is demonstrated to give reliable results even when applied in the discrete case. In addition, another advancement for the application of the Sobol method is done by studying the variation of these indexes with respect to some factors of the model or some experimental conditions. The consequences and conclusions derived from the study of this variation help in determining different characteristics and information about the inputs. Moreover, these inferences allow the indication of the best experimental conditions at which estimation of the inputs can be done.

The dissertation consists of two parts. The first part (Chapter 1 to 4) is on some contributions to the development of a non-linear analysis on the quintessential fractal set Sierpinski gasket and its probabilistic interpretation. The second part (Chapter 5) is on the asymptotic tail decays for suprema of stochastic processes satisfying certain conditional increment controls. Chapters 1, 2 and 3 are devoted to the establishment of a theory of backward problems for non-linear stochastic differential equations on the gasket, and to derive a probabilistic representation to some parabolic type partial differential equations on the gasket. In Chapter 2, using the theory of Markov processes, we derive the existence and uniqueness of solutions to backward stochastic differential equations driven by Brownian motion on the Sierpinski gasket, for which the major technical difficulty is the exponential integrability of quadratic processes of martingale additive functionals. A Feynman-Kac type representation is obtained as an application. In Chapter 3, we study the stochastic optimal control problems for which the system uncertainties come from Brownian motion on the gasket, and derive a stochastic maximum principle. It turns out that the necessary condition for optimal control problems on the gasket consists of two equations, in contrast to the classical result on &Ropf;^d, where the necessary condition is given by a single equation. The materials in Chapter 2 are based on a joint work with Zhongmin Qian (referenced in Chapter 2). Chapter 4 is devoted to the analytic study of some parabolic PDEs on the gasket. Using a new type of Sobolev inequality which involves singular measures developed in Section 4.2, we establish the existence and uniqueness of solutions to these PDEs, and derive the space-time regularity for solutions. As an interesting application of the results in Chapter 4 and the probabilistic representation developed in Chapter 2, we further study Burgers equations on the gasket, to which the space-time regularity for solutions is deduced. The materials in Chapter 4 are based on a joint work with Zhongmin Qian (referenced in Chapter 4). In Chapter 5, we consider a class of continuous stochastic processes which satisfy the conditional increment control condition. Typical examples include continuous martingales, fractional Brownian motions, and diffusions governed by SDEs. For such processes, we establish a Doob type maximal inequality. Under additional assumptions on the tail decays of their marginal distributions, we derive an estimate for the tail decay of the suprema (Theorem 5.3.2), which states that the suprema decays in a manner similar to the margins of the processes. In Section 5.4, as an application of Theorem 5.3.2, we derive the existence of strong solutions to a class of SDEs. The materials in this chapter is based on the work [44] by the author (Section 5.2 and Section 5.3) and an ongoing joint project with Guangyu Xi (Section 5.4).

Made available in DSpace on 2016-12-06T17:07:07Z (GMT). No. of bitstreams: 1 Alexandre Azevedo.pdf: 1554836 bytes, checksum: 44119494437e2ee610d59d403183e1da (MD5) Previous issue date: 2015-11-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / One of the possible mechanisms that explain the increased speed forward walking (FW) after the training backward walking (BW) in people with hemiplegia could be an increased recruitment of ankle muscles during task BW. The goal of this study is compare the muscle activation (dorsi-flexors and plantarflexors) and the range of motion of the ankle during the tasks of FW and BW in subjects with hemiparesis after stroke and healthy control subjects. The study included 12 subjects (65 ± 9 years) with chronic hemiparesis (60 ± 40 months post-stroke) and mild to moderate impairment of lower limb (LL) (FMLL 25.0 ± 4.7 points). For the control group participated in 6 healthy subjects (62.2 ± 4.6 years). The range of motion (ROM) passive isokinetic torque of the ankle at 30º / sec and corresponding EMG activity in plantarflexor muscles (PF) - Medial gastrocnemius (MG) and soleus (SOL) and dorsiflexion (DF) - Tibialis anterior (TA ) and peroneus longus (PL) was compared between the legs with ANOVA oneway. They assessed the EMG activity of the muscles and the kinematics of the ankle during the AF and AT separately in each gait sub-phase: first double support (1DS), simple support (SS), second double support (2DS) and balance sheet (BL). Data were analyzed by ANOVA, taking as factors the direction (FW and BW) and LL paretic (LLP), non-paretic (LLNP) and control (CTL). The CTL group presented DF ROM greater than the LLNP and the LLP. The PF was greater torque in relation to LLNP and LLP and LLNP was greater than in the LLP. The DF torque was lower in the LLP compared to CTL and LLNP. The spatiotemporal variables stride length, stride length and walking speed were higher in AF and higher in CTL compared to LLNP and LLP. 1DS in stages, SS and 2DS ankle ROM was higher in CTL that LLNP and LLP. In 2DS and BL CTL showed higher ROM in the BW that in FW, and 2DS in the LLNP and LLP ROM in FW was higher. The CTL group showed higher EMG activity of DF (TA and PL) and PF (MG and SOL) for all sub-phases, and only in the BL RMS of all analyzed muscles was higher in FW compared to BW. In general the CTL group had higher amplitudes and higher EMG activity that the LLP and LLNP at all stages of the march. In 2DS and BL ankle ROM was higher in the BW in the CTL group, but not in LLNP and LLP. The swing phase the EMG activity of DF and PF was higher in FW compared to FL. Future studies should evaluate whether the lower ROM identified in kinematics is related to an ankle muscle co-activation in this population. / Um dos possíveis mecanismos que explicaria o aumento da velocidade do andar para frente (AF) após o treinamento do andar para trás (AT) em pessoas com hemiparesia poderia ser um maior recrutamento da musculatura do tornozelo durante a tarefa de AT. Pretendeu-se com esta pesquisa comparar a ativação muscular de dorsi e plantiflexores e a amplitude de movimento do tornozelo durante as tarefas de AF e AT entre sujeitos com hemiparesia pós-AVE e indivíduos controle saudáveis. Participaram do estudo 12 indivíduos (65±9 anos) com hemiparesia crônica (60±40 meses pós-AVE) e comprometimento leve a moderado de membro inferior (MI) (FMMI 25,0±4,7 pontos). Para o grupo controle participaram 6 indivíduos saudáveis (62,2±4,6 anos). A amplitude de movimento (ADM) passiva, o torque isocinético do tornozelo a 30º/s e a atividade EMG correspondente na musculatura plantiflexora (PF) (Gastrocnêmio Medial (GM) e Solear (SOL)) e dorsiflexora (DF) (Tibial Anterior (TA) e Fibular Longo (FL)) foram comparados entre os MI com a ANOVA de uma via. Foram avaliadas a atividade EMG da musculatura e a cinemática do tornozelo durante o AF e o AT separadamente em cada subfase da marcha: primeiro duplo apoio (1DA), apoio simples (AS), segundo duplo apoio (2DA) e balanço (BL). Os dados foram analisados através da ANOVA de duas vias, tendo como fatores a direção (AF e AT) e o MI (parético (MIP), não parético (MINP) e controle (CTL)). O grupo CTL apresentou ADM de DF maior que o MINP e que o MIP. O torque de PF foi maior no CTL em relação ao MINP e ao MIP e no MINP foi maior que no MIP. O torque de DF foi menor no MIP em relação ao CTL e MINP. As variáveis espaço-temporais comprimento da passada, comprimento do passo e velocidade de marcha foram maiores no AF em relação ao AT e maiores no CTL comparativamente ao MINP e MIP. Nas fases 1DA, AS e 2DA a ADM do tornozelo foi maior nos CTL que MINP e MIP. No 2DA e BL os CTL apresentaram maior ADM no AT que no AF, sendo que no 2DA o MINP e MIP a ADM no AF foi maior. O grupo CTL apresentou maior atividade EMG dos DF (TA e FL) e PF (GM e SOL) durante todas as subfases, sendo que apenas no BL a RMS de todos os músculos analisados foi maior no AF comparativamente ao AT. No 2DA e no BL a ADM do tornozelo foi maior no AT no grupo CTL, mas não nos MINP e MIP. O grupo CTL apresentou maiores amplitudes e maior atividade EMG que o MIP e MINP em todas as fases da marcha. Na fase de balanço a atividade EMG dos DF e PF foi maior no AF comparativamente ao AT.