945 resultados para second central moment


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A full two-fluid model of reacting gas-particle flows with an algebraic unified second-order moment (AUSM) turbulence-chemistry model is used to simulate Beijing coal combustion and NOx formation. The sub-models are the k-epsilon-kp two-phase turbulence model, the EBU-Arrhenius volatile and CO combustion model, the six-flux radiation model, coal devolatilization model and char combustion model. The blocking effect on NOx formation is discussed. In addition, the chemical equilibrium analysis is used to predict NOx concentration at different temperature. Results of CID simulation and chemical equilibrium analysis show that, optimizing air dynamic parameters can delay the NOx formation and decrease NOx emission, but it is effective only in a restricted range. In order to decrease NOx emission near to zero, the re-burning or other chemical methods must be used.

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Plus de la moitié des adolescents suicidaires dont une large proportion présente un trouble de personnalité limite (TPL) abandonnent leur traitement. Les conséquences de leur défection sont préoccupantes considérant la récurrence de leurs conduites suicidaires et le fait que cette pathologie augmente le risque d’une évolution défavorable à l’âge adulte. À partir d’une méthode de théorisation ancrée constructiviste, cette étude visait à comprendre les processus associés à l’instabilité du mode de consultation des adolescents avec TPL. Elle a permis de spécifier les vulnérabilités à l’abandon des adolescents avec TPL et celles de leurs parents et mis au jour que l’atténuation des problèmes d’accessibilité, la préparation au traitement, l’adaptation des soins aux particularités du TPL et finalement la prise en compte de la disposition à traiter des soignants constituent des réponses déterminantes pour leur engagement. Les processus de désengagement ont également été spécifiés. Des perceptions négatives à l’égard du traitement, du soignant ou du fait d’être en traitement génèrent une activation émotionnelle. Celle-ci induit ensuite des attitudes contre-productives qui évoluent vers des comportements francs de désengagement. Dans ce contexte, des réponses du dispositif de soins telles une régulation insuffisante de l’engagement, des impairs thérapeutiques et des demandes paradoxales précipitent l’abandon de traitement. Finalement, les processus impliqués dans l’abandon de traitement ont été formalisés dans le Modèle de l’engagement et de l’abandon de traitement des adolescents avec TPL. Celui-ci illustre que des processus distincts caractériseraient les abandons précoces et les abandons tardifs des adolescents avec TPL. L’abandon précoce résulterait de l’échec du dispositif de soins à profiter de l’impulsion de la demande d’aide pour engager l’adolescent et le parent lors de ce premier moment critique de sa trajectoire de soins. En contrepartie, les abandons tardifs traduiraient les défaillances du dispositif de soins à adopter des mesures correctives pour les maintenir en traitement lors d’un deuxième moment critique marqué par leur désengagement. Les taux d’abandon de traitement de ces jeunes pourraient être diminués par un dispositif de soins qui reconnaît les périls inhérents au traitement de cette clientèle, se montre proactif pour résoudre les problèmes de désengagement, intègre des mécanismes de soutien aux soignants et favorise une pratique réflexive.

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A obesidade é, hoje em dia, considerada um transtorno multifatorial, ou seja, resultante de diversos fatores: bio-psico-sociais. Sendo que os fatores psiquiátricos tais como a ansiedade e a depressão, têm vindo a ter cada vez mais importância, existindo fortes evidências em como a obesidade não é só um transtorno orgânico. Deste modo, torna-se fundamental perceber qual o efeito que a Atividade Física (AF) e o exercício podem ter em transtornos tais com a depressão e a ansiedade, em indivíduos com obesidade severa. Com a realização deste estágio pretendeu-se desenvolver diferentes estratégias de intervenção com este tipo de população, no que diz respeito à prescrição e planeamento de sessões teórico-práticas, consultas de prescrição de exercício e também averiguar qual a influência que a Atividade Física pode ter nos sintomas de Ansiedade e Depressão, em indivíduos com obesidade severa. Foi realizada uma revisão sistemática da literatura na qual se investigou o efeito que o exercício e a AF podem ter na saúde mental, mais concretamente nos sintomas de ansiedade e depressão neste tipo de população. Dos estudos analisados foi possível concluir que indivíduos que são sujeitos a um programa multidisciplinar que inclui atividade física apresentam melhorias quer no que diz respeito à qualidade de vida (2 estudos) como no que diz respeito à saúde mental (4 estudos). Apesar das diferenças metodológicas entre os estudos, concluiu-se que, de uma forma geral, os programas que incluem atividade física, mais especificamente 2 a 3 horas por semana de exercício aeróbio de intensidade moderada a vigorosa, levam a melhorias consideráveis na saúde mental, nos níveis de depressão e de ansiedade. Relativamente às sessões teórico-práticas realizadas, os resultados obtidos com a intervenção realizada não foram significativos tanto no que diz respeito aos sintomas de ansiedade tanto como os de depressão. No que diz respeito às consultas realizadas no Hospital de Santa Maria, foi possível concluir que os utentes avaliados apresentavam na sua maioria comportamentos sedentários. No entanto, apenas um utente foi avaliado pela segunda vez tendo sido reportadas algumas melhorias no que diz respeito à capacidade cardiovascular do primeiro para o segundo momento de avaliação.

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This thesis argues that ontological terror is a burgeoning condition ingrained within our collective human psyche which can only be artistically represented through carefully chosen veils, two of which can be made explicit through an analysis of the aesthetic conventions of the liminal uncanny and the traumatic sublime. Artistic depiction of terror is realisable only through the reflections that are cast from it, the sum of which, make up these veils. The experience of terror is intimately aligned with the threat inherent within an experience of trauma or grief and the visual performance outcome of the Masters research Aviary, produced at the Living Museum of the West in 2006 is best understood as a representation of the mournful and desolate reflections that shimmered off a central moment of unspeakable terror.

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Esta tese é uma reflexão sobre a construção de escritas da História do Brasil em museus, a partir da década de 1920, momento fulcral para o estabelecimento de uma “pedagogia da nacionalidade” republicana, que tem por suporte o discurso museal. Alguns dos esforços político-pedagógicos dessas instituições foram observados, com o objetivo de compreender as principais características de um paradigma educativo para o saber histórico nos museus. Assim, a análise das comemorações cívicas, dos guias de divulgação e das exposições permitiu uma aproximação das ativações memoriais ensejadas pelos atores dos museus, com atenção para as continuidades, as negociações e as transformações dos projetos, especialmente em sua dimensão pedagógica. O Museu Mariano Procópio foi selecionado para a realização de um estudo de caso, tanto por suas especificidades, que nos induzem a pensar o “concerto” dos museus nacionais a partir do interior do país como pela relevância de seu acervo e pela intensidade de ações educativas desenvolvidas na gestão de Geralda Armond (1944-1980). A gestão Armond é o foco da tese, sendo marcada pela defesa da continuidade institucional e do enquadramento da memória da família Lage; pela luta pela sustentação material do Museu, inclusive com uma forte aproximação com o regime civil e militar; e pela busca da profissionalização de quadros e do dinamismo das ações. Os resultados atentam para a multiplicidade e fragilidade na construção identitária do Museu, associada ao fato de ser um museu “municipal”. Uma situação que explica, ao menos em parte, seu esquecimento no cenário nacional a despeito de seu acervo expressivo e das articulações encetadas com o sistema escolar, por meio do fortalecimento do sentido cívico de suas ações pedagógicas.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Im Zuge dieser Arbeit ist ein Massenspektrometer zur flugzeuggetragenen Messung von HNO3 und HONO auf dem neuen deutschen Forschungsflugzeug HALO aufgebaut worden (AIMS - Atmospheric chemical Ionization Mass Spectrometer). Die Ionisation der HNO3- und HONO-Moleküle erfolgt chemisch durch Reaktion mit SF5- -Ionen. Basierend auf den Ergebnissen von Laborversuchen wurden die Betriebsparameter optimiert, die Einzelkomponenten im HALO-Rack zusammengestellt und eine Einlassleitung entworfen, die Wandeffekte minimiert und Untergrundmessungen und HNO3-Kalibrationen im Flug ermöglicht. Die Empfindlichkeit der Messung von HNO3 und HONO wurde ebenso im Labor untersucht wie Interferenzen mit Wasserdampf und Ozon. Die HONO-Vergleichskampagne FIONA am Europäischen Photoreaktor (EUPHORE) in Valencia war die erste Messkampagne mit AIMS. Bei den offenen Vergleichsmessungen stimmten die von AIMS gemessenen HONO-Mischungsverhältnisse innerhalb +-20% mit dem Median von 9 weiteren HONO-Messungen überein. Die ersten flugzeuggetragenen Messungen mit AIMS werden im Verlauf der HALO-Missionen ML-CIRRUS und TACTS stattfinden. Neben dem Aufbau und der Charakterisierung von AIMS war die Analyse der Aufnahme von HNO3 in Eispartikel von Kondensstreifen und Zirren Gegenstand dieser Arbeit. Die Aufnahme von HNO3 in Kondensstreifeneispartikel wurde erstmals systematisch anhand einer Flugzeugmesskampagne (CIRRUS-III) untersucht. Während CIRRUS-III im November 2006 wurden Zirren und zufällig knapp 40 persistente Kondensstreifen über Deutschland und Nordeuropa beprobt. Die Messungen fanden in Höhen zwischen 10 und 11.5 km und bei Temperaturen zwischen 210 und 230 K statt. Die HNO3-Konzentration wurde mit Hilfe von NOy-Messungen bestimmt. Im Mittel war in Kondensstreifen ein größerer Anteil des Gesamt-HNO3 in den Eispartikeln gebunden (6 %) als in Zirren (3 %). Das Gasphasenäquivalent des eisgebundenen HNO3 betrug in Zirren durchschnittlich 6 pmol/mol, in Kondensstreifen 14 pmol/mol und in jungen Kondensstreifen (Alter<1 h) 21 pmol/mol. Das Mischungsverhältnis von HNO3 zu H2O in Eispartikeln war in Kondensstreifen leicht höher als in Zirren unter ähnlichen meteorologischen Bedingungen. Ursächlich für die höheren Werte in persistenten Kondensstreifen sind wahrscheinlich die hohen HNO3-Konzentrationen in den Abgasfahnen der Flugzeuge bei der Kondensstreifenbildung. Die beobachtete Abnahme des HNO3/H2O-Molverhältnisses mit zunehmendem Effektivdurchmesser der Eispartikel deutet an, dass die HNO3-Konzentrationen in Eispartikeln von jungen Kondensstreifen durch die Aufnahme von Abgas-HNO3 in die gefrierenden Aerosolpartikel bestimmt wird. Die Konzentrationen in älteren Kondensstreifen werden zunehmend durch das Vergraben von Umgebungs-HNO3 in wachsenden Eispartikeln kontrolliert. Diese Studie leistet einen Beitrag zu einem besseren Prozessverständnis der HNO3-Aufnahme in atmosphärische Eispartikel. Sie motiviert die Nutzung persistenter Kondensstreifen als atmosphärisches Labor zur Untersuchung der Spurengasaufnahme in wachsende Eispartikel.

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Colon cancer is the second leading cause of cancer mortality in the U.S. Surgery is the only truly effective human colon cancer (HCC) therapy due to marked intrinsic drug resistance. The inefficacy of therapies developed for metastatic HCC suggests that advances in colon cancer chemoprevention and chemotherapy will be needed to reduce HCC mortality. The dietary fiber metabolite butyrate (NaB) is a candidate cancer chemopreventive agent that inhibits growth, promotes differentiation and stimulates apoptosis of HCC cells. Epidemiological and experimental studies suggest that dietary fiber protects against the development of HCC, however, recent large prospective trials have not found significant protection. ^ The first central hypothesis of this dissertation project is that the diversity of phenotypic changes induced by NaB in HCC cells includes molecular alterations that oppose its chemopreventive action and thereby limit its efficacy. We investigated the effect of NaB on the expression/activity of epidermal growth factor receptor (EGFR) and cyclooxygenase-2 (COX-2) in HCC HT29 cells. NaB treatment induced a 13-fold increase in EGFR expression in concert with its chemopreventive action in vitro, i.e., induction of growth suppression and G1 arrest, apoptosis and a differentiated phenotype. NaB-induced EGFR was active based on multiple lines of evidence. The EGFR was: (1) heavily phosphorylated at Tyrosine (P-Tyr); (2) associated with the cytoskeleton; (3) localized at the cell surface, and activated in response to EGF; and (4) NaB treatment of the cells induced activation of the EGFR effector Erk1/2. NaB treatment also induced a 7-fold increase in COX-2 expression. The NaB-induced COX-2 was active based on significantly increased PGE2 production. ^ The second central hypothesis is that NaB treatment would render HCC cells more chemosensitive to chemotherapy agents based on the increased apoptotic index induced by NaB. NaB treatment chemosensitized HT29 cells to 5-FU and doxorubicin, despite increases in the expression of P-glycoprotein and a related drug resistance protein (MRP). ^ These results raise the intriguing possibility that the chemopreventive effects of fiber may require concomitant treatment with EGFR and/or COX-2 inhibitors. Similarly, NaB may be a rational drug to combine with existing chemotherapeutic agents for the management of advanced HCC patients. ^

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This paper examines three types of industrialization that have occurred in East Asia: the Japanese, Chinese and generic Asian models. Industrial policies in Japan and the Republic of Korea (ROK) initially protected local companies from foreign investors by imposing high tariffs on foreign investors. But Japan began introducing liberalization policies to attract foreign direct investment (FDI) in the 1960s, and the ROK began to welcome foreign technology in the 1970s. Meanwhile, the governments of the ASEAN countries and Taiwan established export-processing zones (EPZ) to invite FDI by offering preferential treatment, such as tax deductions and exemptions. China adopted similar industrial policies and also established EPZs, attracting the capital and know-how of multinationals and thereby strengthening the international competitiveness of local enterprises. This paper reaches the following three conclusions. First, it would have been difficult for East Asian countries to grow without FDI. Second, central governments were a crucial factor in these countries' growth strategies. Third, EPZs offering preferential treatment can effectively enhance aggregate growth in developing countries, and the Asian experience shows that this strategy can be applied to other countries that satisfy certain preconditions.

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This thesis argues that the legal framework in Ireland for specialist palliative care is inadequate and consequently a more appropriate legal framework must be identified. This research is guided by three central research questions. The first central research question examines the legitimacy of the distinction between specialist palliative care and euthanasia. The second central research question asks what legal framework currently exists in Ireland for specialist palliative care. The third central research question examines an alternative legal framework for specialist palliative. This thesis is composed of seven chapters. The first Chapter is an introduction to the thesis and defines the terminology and the central research questions. Chapter Two explores the development and practice of palliative care in Ireland. Chapter Three examines the distinction in criminal law between specialist palliative care practices and euthanasia. Chapter Four examines the human rights framework for specialist palliative care. Chapter Five critiques the regulatory framework in Ireland for specialist palliative care. Having gained a thorough understanding of palliative care and the related legal framework, this thesis then engages in comparative analysis of the Netherlands which is used as a source of ideas for reform in Ireland. Chapter Seven is the concluding chapter and, in it, the main findings of this thesis are summarised. The main findings being that: the distinction between specialist palliative care and euthanasia is not sufficiently supported by justifications such as a double effect or the acts and omissions distinction, there is no clear decision-making framework in Ireland for specialist palliative care, and the current legal framework lacks clarity and does not promote consistency between providers of specialist palliative care. This Chapter also proposes that detailed professional standards and guidelines are likely to be the most appropriate way to effect individual and institutional change in the provision of specialist palliative care.

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Today , Providing drinking water and process water is one of the major problems in most countries ; the surface water often need to be treated to achieve necessary quality, and in this way, technological and also financial difficulties cause great restrictions in operating the treatment units. Although water supply by simple and cheap systems has been one of the important objectives in most scientific and research centers in the world, still a great percent of population in developing countries, especially in rural areas, don't benefit well quality water. One of the big and available sources for providing acceptable water is sea water. There are two ways to treat sea water first evaporation and second reverse osmosis system. Nowadays R.O system has been used for desalination because of low budget price and easily to operate and maintenance. The sea water should be pretreated before R.O plants, because there is some difficulties in raw sea water that can decrease yield point of membranes in R.O system. The subject of this research may be useful in this way, and we hope to be able to achieve complete success in design and construction of useful pretreatment systems for R.O plant. One of the most important units in the sea water pretreatment plant is filtration, the conventional method for filtration is pressurized sand filters, and the subject of this research is about new filtration which is called continuous back wash sand filtration (CBWSF). The CBWSF designed and tested in this research may be used more economically with less difficulty. It consists two main parts first shell body and second central part comprising of airlift pump, raw water feeding pipe, air supply hose, backwash chamber and sand washer as well as inlet and outlet connections. The CBWSF is a continuously operating filter, i.e. the filter does not have to be taken out of operation for backwashing or cleaning. Inlet water is fed through the sand bed while the sand bed is moving downwards. The water gets filtered while the sand becomes dirty. Simultaneously, the dirty sand is cleaned in the sand washer and the suspended solids are discharged in backwash water. We analyze the behavior of CBWSF in pretreatment of sea water instead of pressurized sand filter. There is one important factor which is not suitable for R.O membranes, it is bio-fouling. This factor is defined by Silt Density Index (SDI).measured by SDI. In this research has been focused on decreasing of SDI and NTU. Based on this goal, the prototype of pretreatment had been designed and manufactured to test. The system design was done mainly by using the design fundamentals of CBWSF. The automatic backwash sand filter can be used in small and also big water supply schemes. In big water treatment plants, the units of filters perform the filtration and backwash stages separately, and in small treatment plants, the unit is usually compacted to achieve less energy consumption. The analysis of the system showed that it may be used feasibly for water treating, especially for limited population. The construction is rapid, simple and economic, and its performance is high enough because no mobile mechanical part is used in it, so it may be proposed as an effective method to improve the water quality and consequently the hygiene level in the remote places of the country.

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The problem of estimating the three-dimensional rotational parameters of a rigid body from its monocular image data has been considered using the method of moment invariants. Second- and third-order moment invariants are used to construct the feature vector for the scale and orientation independent identification of the camera view axis direction in the body-fixed reference frame. The camera rotation angle about the view axis is derived from second-order central moments. The relative attitude of the rigid body is then expressed in terms of quaternion parameters to model the outputs of a video sensor in attitude control simulations. Experimental results and simulation outputs are presented using the mathematical model of a spacecraft.

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The long- and short-period body waves of a number of moderate earthquakes occurring in central and southern California recorded at regional (200-1400 km) and teleseismic (> 30°) distances are modeled to obtain the source parameters-focal mechanism, depth, seismic moment, and source time history. The modeling is done in the time domain using a forward modeling technique based on ray summation. A simple layer over a half space velocity model is used with additional layers being added if necessary-for example, in a basin with a low velocity lid.

The earthquakes studied fall into two geographic regions: 1) the western Transverse Ranges, and 2) the western Imperial Valley. Earthquakes in the western Transverse Ranges include the 1987 Whittier Narrows earthquake, several offshore earthquakes that occurred between 1969 and 1981, and aftershocks to the 1983 Coalinga earthquake (these actually occurred north of the Transverse Ranges but share many characteristics with those that occurred there). These earthquakes are predominantly thrust faulting events with the average strike being east-west, but with many variations. Of the six earthquakes which had sufficient short-period data to accurately determine the source time history, five were complex events. That is, they could not be modeled as a simple point source, but consisted of two or more subevents. The subevents of the Whittier Narrows earthquake had different focal mechanisms. In the other cases, the subevents appear to be the same, but small variations could not be ruled out.

The recent Imperial Valley earthquakes modeled include the two 1987 Superstition Hills earthquakes and the 1969 Coyote Mountain earthquake. All are strike-slip events, and the second 1987 earthquake is a complex event With non-identical subevents.

In all the earthquakes studied, and particularly the thrust events, constraining the source parameters required modeling several phases and distance ranges. Teleseismic P waves could provide only approximate solutions. P_(nl) waves were probably the most useful phase in determining the focal mechanism, with additional constraints supplied by the SH waves when available. Contamination of the SH waves by shear-coupled PL waves was a frequent problem. Short-period data were needed to obtain the source time function.

In addition to the earthquakes mentioned above, several historic earthquakes were also studied. Earthquakes that occurred before the existence of dense local and worldwide networks are difficult to model due to the sparse data set. It has been noticed that earthquakes that occur near each other often produce similar waveforms implying similar source parameters. By comparing recent well studied earthquakes to historic earthquakes in the same region, better constraints can be placed on the source parameters of the historic events.

The Lompoc earthquake (M=7) of 1927 is the largest offshore earthquake to occur in California this century. By direct comparison of waveforms and amplitudes with the Coalinga and Santa Lucia Banks earthquakes, the focal mechanism (thrust faulting on a northwest striking fault) and long-period seismic moment (10^(26) dyne cm) can be obtained. The S-P travel times are consistent with an offshore location, rather than one in the Hosgri fault zone.

Historic earthquakes in the western Imperial Valley were also studied. These events include the 1942 and 1954 earthquakes. The earthquakes were relocated by comparing S-P and R-S times to recent earthquakes. It was found that only minor changes in the epicenters were required but that the Coyote Mountain earthquake may have been more severely mislocated. The waveforms as expected indicated that all the events were strike-slip. Moment estimates were obtained by comparing the amplitudes of recent and historic events at stations which recorded both. The 1942 event was smaller than the 1968 Borrego Mountain earthquake although some previous studies suggested the reverse. The 1954 and 1937 earthquakes had moments close to the expected value. An aftershock of the 1942 earthquake appears to be larger than previously thought.