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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

Luz e experimentaÃÃo no retrato fotogrÃfico / Light and Experimentation in Photographic Portraiture.

Deborah AraÃjo Muniz 26 October 2016 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Este estudo tem o objetivo de investigar o uso expressivo da luz e da experimentaÃÃo na composiÃÃo artÃstica do retrato fotogrÃfico. Considera-se nesta pesquisa a composiÃÃo fotogrÃfica pensada em relaÃÃo a luz, como elemento estÃtico responsÃvel por configurar o que à posto em cena e criar percepÃÃes no retrato, baseado na concepÃÃo de que ao retratar um determinado assunto, o fotÃgrafo propÃe expressÃ-lo de alguma maneira, pensa em uma ideia de iluminaÃÃo que produza a atmosfera e o efeito expressivo desejado. A luz se manifesta no retrato de diferentes formas, conforme os princÃpios de composiÃÃo subjetivas, correspondentes ao que o fotÃgrafo quer expressar do que retrata. Aliada a atividade experimental na composiÃÃo fotogrÃfica, a experimentaÃÃo implica um ato de descobertas e escolhas inerentes a criaÃÃo, que remetem a materializaÃÃo da expressividade artÃstica no retrato, pois à atravÃs da escrita fotogrÃfica que os profissionais criam suas imagens. Nesse sentido, este estudo examina a composiÃÃo artÃstica dos retratos produzidos por Camila Mangueira e Tiago Santana, a iluminaÃÃo e a atividade experimental como maneiras de dar forma ao retrato fotogrÃfico. A concepÃÃo metodolÃgica utiliza-se de uma pesquisa bibliogrÃfica, descritiva e exploratÃria em que se constatou que a iluminaÃÃo à uma potÃncia capaz de produzir efeitos extraordinÃrios sobre a imagem, criar atmosferas distintas e ser responsÃvel pela expressividade da imagem, manifestando-se na imagem atravÃs dos elementos luz e sombra, sua cor, sua direÃÃo, sua intensidade e seu carÃter em interaÃÃo com os demais elementos do quadro, que atravÃs do manuseio experimental, acentuam caracterÃsticas prÃprias do assunto do retrato e atribuem significados sugestivos e evocativos ao que se retrata. / This study aims to investigate the expressive use of light and experimentation in the artistic composition of the photographic portrait. It is considered in this research the photographic composition thought to the light, as an aesthetic element responsible for setting up what is put in and create perceptions in the picture, based on the concept that to portray a certain subject, the photographer proposes express it somehow, you think of an idea of lighting that produces the atmosphere and the desired expressive effect. The light is manifested in the picture in different ways, according to the principles of subjective composition, corresponding to what the photographer wants to express what portrays. Combined with experimental activity in the photographic composition, experimentation implies an act of discovery and creation inherent in choices that lead to materialization of artistic expression in the picture. It is through the photographic writing photographers create their images. In this sense, the study examines the artistic composition of pictures produced by Camila hose and Tiago Santana, lighting and experimental activity as ways to shape the photographic portrait. The methodological design is literature, descriptive and exploratory research. Found that the lighting is a power capable of producing extraordinary effects on the image, creating different atmospheres and be responsible for the expressiveness of the image, manifesting the image through the light elements and shadow, its color, its direction, its intensity, its character in interaction with other frame elements, through experimental manipulation, stress characteristics of the portrait subject and attribute meanings suggestive and evocative to portraying.
312

Uma solução para qualidade de contexto baseada em ontologia e lógica nebulosa com aplicação em monitoramento de sinais vitais em UTI / An approach for quality of context based on ontology and fuzzy logic: a case study on vital sign monitoring at ICU

Sena, Márcio Vinícius Oliveira 03 May 2016 (has links)
Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2016-08-10T13:23:57Z No. of bitstreams: 2 Dissertação - Márcio Vinicius Oliveira Sena - 2016.pdf: 1222160 bytes, checksum: ca880e6a18b3f494d8b0e578a83d6b24 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-08-10T13:40:14Z (GMT) No. of bitstreams: 2 Dissertação - Márcio Vinicius Oliveira Sena - 2016.pdf: 1222160 bytes, checksum: ca880e6a18b3f494d8b0e578a83d6b24 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-08-10T13:40:14Z (GMT). No. of bitstreams: 2 Dissertação - Márcio Vinicius Oliveira Sena - 2016.pdf: 1222160 bytes, checksum: ca880e6a18b3f494d8b0e578a83d6b24 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2016-05-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / More than a decade after the first training paradigm Computer Context Sensitive, the term Quality of Context (QoC) emerged in a setting filled with services that provide userapplication interactions seamlessly, highlighting the need for managers of information context. These infrastructures that handle context information, CMS (Context Management System), are full of inputs and outputs relevant data or not. The relevance of information is studied by many lines of sensitive computing the context, including QoC. Although there are a large number of QoC metrics, the literature still lacks general values to characterize the relevance of context information, ie from metrics produce an overall value that represents the importance of information. The objective of this work is to propose, from fuzzy logic, a combination of metrics in order to produce a QoC value for each information received, and possible disposal, if this information does not meet the expected relevance, described in this work by policies of QoC. In order to disseminate the context of consumers that information produced, this research proposes also, from an ontology domain independent QoC, annotate semantically the data that refer to the quality of information, thus avoiding the need for new measures in a short-term time. Finally, this paper presents the application of the solutions found in a case study of monitoring vital signs of patients in ICU. / Mais de uma década depois da primeira formulação do paradigma de Computação Sensível ao Contexto, o termo de Quality of Context (QoC) emergiu em um cenário repleto de serviços que proporcionam interações usuário-aplicação de forma transparente, evidenciando a necessidade de gerenciadores de informações de contexto. Estas infraestruturas que manipulam informações de contexto, CMS (Context Management System), estão repletas de entradas e saídas de dados relevantes ou não. A relevância das informações é objeto de estudo de muitas linhas da computação sensível a contexto, inclusive QoC. Embora haja uma infinidade de métricas de QoC, a literatura ainda carece de valores gerais para caracterizar a relevância de uma informação de contexto, ou seja, a partir de métricas, produzir um valor geral que represente a importância de uma informação. O objetivo deste trabalho é propor, a partir de Lógica Nebulosa, uma combinação de métricas, a fim de produzir um valor de QoC para cada informação recebida, sendo possível o descarte, caso essa informação não atenda a relevância esperada, descrita nesse trabalho por políticas de QoC. Buscando disseminar aos consumidores de contexto essas informações produzidas, esta pesquisa propôe também, a partir de uma ontologia de QoC independente de domínio, anotar semanticamente os dados que se referem a qualidade da informação, evitando assim a necessidade de novas medições em um prazo curto de tempo. Por fim, este trabalho apresenta a aplicação das soluções encontradas em um estudo de caso de monitoramento de sinais vitais de pacientes em UTIs.
313

Explorações, experimentações e intervenções em São Paulo: estudo de caso sobre o Programa Jovens Urbanos / Explorations, experimentations and interventions in Sao Paulo: a case study about the Urban Youth Program

Aboboreira, Ariane 26 May 2014 (has links)
Made available in DSpace on 2016-04-26T14:54:45Z (GMT). No. of bitstreams: 1 Ariane Aboboreira.pdf: 901313 bytes, checksum: 710ecbd2fa92f7c051df126196b7b26d (MD5) Previous issue date: 2014-05-26 / This investigation has as its main objective to analyse, in the specific situation of the Program "Urban Youth" - CENPEC and Itau Social Foundation - what are the impacts on their young participants within their experimentations in Sao Paulo metropolitan area. By evaluating the proposal of the program - which combines explorations in the city, experimentations of new technologies and interventions on the neighborhoods in which the participants are residents - this investigation intends to: understand how the movement of the young participants around the city - and the perception they acquire in the relation with new ways of appropriation and uses of the metropolis - resonates in the resignifications they make about their resident neighborhood; it is also the objective, to answer how these mobile perceptions interfere in the interventions promoted by the end of the "Urban Youth" program. The young participant's narrative is the basis of the methodological axis of this investigation but the research also has as fundamentals:the evaluation of official documents distributed by the "Urban Youth" program, blog analysis; and also with ethnografical practices centered on field research and based on participant observation and interviews / Esta investigação tem como principal objetivo analisar, na situação particular do Programa Jovens Urbanos - CENPEC e Fundação Itaú Social - quais os impactos provocados em seus jovens participantes Programa em suas experimentações na metrópole paulistana. Por meio da análise da proposta do referido Programa que combina explorações na cidade de São Paulo, experimentações de novas tecnologias e intervenções nos bairros de origem , esta investigação visa: compreender como o caminhar dos jovens pela cidade e a percepção que adquirem na relação com novas formas de apropriações e usos da metrópole ressoa nas ressignificações que fazem a respeito do seu bairro de origem; objetiva, também, responder sobre como tais mobilidades perceptivas interferem nas intervenções que promovem ao final do programa por meio dos Projetos Jovens. Ainda que as narrativas juvenis constituam o eixo metodológico privilegiado desta investigação, a pesquisa fundamentou-se, ainda, nos seguintes procedimentos que compuseram o protocolo metodológico: leitura de documentos oficiais disponibilizados pelo Programa Jovens Urbanos , análise dos blogs; e finalmente, em práticas etnográficas centradas na pesquisa de campo e baseada na observação participante e em entrevistas em profundidade
314

Investigations of Biotremors in the Veiled Chameleon (Chamaeleo calyptratus)

Laslie, Kathryn C 01 July 2018 (has links)
While substrate-borne vibrations are utilized by different reptile species, true conspecific communication via biotremors has not yet been demonstrated in reptiles. This study follows a preliminary report that the veiled chameleon (Chamaeleo calyptratus) could produce biotremors in communicative contexts. I tested chameleon behavioral sensitivity to vibrations by placing them on a dowel attached to a shaker emitting vibrations of 25, 50, 150, 300, and 600 Hz and then measured their changes in velocity before and after the stimulus. I then paired chameleons in various social contexts [anthropogenic disturbance (human disruption of animal); dominance (malemale; female-female C. calyptratus); courtship (male-female C. calyptratus); heterospecific (C. calyptratus + C. gracilis); and predator-prey (adult + juvenile C. calyptratus)] and used a video camera and accelerometers to record their behavior. This study demonstrates that chameleons produce biotremors and that receivers exhibit a freeze response when exposed to a simulated biotremor stimulus. Furthermore, veiled chameleons produce biotremors in anthropogenic disturbance, conspecific dominance and courtship contexts, and these biotremors are elicited by visual contact with another adult conspecific and heterospecifics. Overall, two classes of biotremor were identified, "hoots” and “rumbles,” which differ significantly in dominant frequency and waveform. No correlation was identified between animal size and dominant frequency of the biotremors they produced as biotremors originate from rapid muscle contractions. Juvenile chameleons of two months of age are able to produce biotremors, suggesting this behavior may have multiple functions. Overall, the data suggest that the veiled chameleon has the potential to utilize substrate-borne vibrational communication during conspecific and possibly heterospecific interactions.
315

Genèse de magmas riches en calcium dans les zones de subduction et sous les rides médio-océaniques : approche expérimentale.

Médard, Etienne 25 June 2004 (has links) (PDF)
Des liquides ultracalciques primitifs (riches en CaO, pauvres en Al2O3) ont été observés dans la plupart des contextes géodynamiques. Les liquides ultracalciques à néphéline normative (uniquement observés dans les arcs) et les liquides ultracalciques à hypersthène normatif (associés à des basaltes tholeiitiques) ne présentent pas de "signature du grenat" et sont donc générés à P < 3 GPa. Les teneurs élevées en CaO jusqu'à 19,0 %) et les rapports CaO/Al2O3 élevés (jusqu'à 1,8) ne peuvent pas être obtenus par fusion de lherzolites fertiles. L'étude des relations de phases au liquidus de deux liquides ultracalciques (à néphéline et à hypersthène normatifs) montre qu'ils sont en équilibre avec olivine et clinopyroxène pour des conditions P/T très différentes. La comparaison de nos résultats et d'expériences de fusion publiées indique que les liquides à hypersthène normatif proviennent de la fusion d'une source réfractaire à olivine+clinopyroxène±orthopyroxène (lherzolite réfractaire ou cumulat wehrlitique) dans le manteau supérieur. Leur présence traduit des températures très élevées (~1400 °C). Les liquides ultracalciques à néphéline normative résultent de la fusion de wehrlites crustales pour des températures plus basses (1200 °C). Des expériences de fusion de wehrlites à amphibole (fréquemment observées en base de croûte d'arc) montrent que la composition des liquides est contrôlée par la déstabilisation de l'amphibole ; ils sont à néphéline normative et deviennent ultracalciques par augmentation du taux de fusion. Ces liquides sont très similaires aux liquides ultracalciques à néphéline normative naturels, qui sont probablement produits selon la réaction amphibole+clinopyroxène = liquide+olivine. La présence d'amphibole permet d'expliquer les teneurs élevées en alcalins et faibles en silice et les faibles températures de fusion. Ces liquides sont des témoins des interactions entre les basaltes magnésiens d'arc et les cumulats crustaux à amphibole.
316

Analysis of Ly-6Chigh CD1lb+ monocytes generated in vitro iniflammatory animal models / Análisis de monocitos Ly-6Chigh CD11b+ generados in vitro en modelos animales de inflamación

Barboza Prado Lopes, Erika 22 April 2013 (has links)
a. Introduction The immune system must detect a wide variety of agents, from viruses to parasitic worms, and distinguish them from the organism's own healthy tissue. However, the immune system needs to be well regulated since a disorder in an immune response can result in autoimmune diseases, tissue destruction, inflammatory diseases and cancer. Within the context of innate immunity, the mononuclear phagocyte system, cells comprising bone marrow progenitors, blood monocytes and tissue macrophages is acquiring great importance in the study of different pathologies and particularly the monocytes/macrophage functions. In this regard, recent studies demonstrate that monocytes present a heterogeneous population of innate cells. Monocyte was found leading to distinct cell populations with various subtypes with distinct functions. Two types of monocytes were identified in mice. Resident monocytes, with a CD11b+CCR2lowLy-6ClowCX3CR1high phenotype, migrate to uninjured tissues after emigration from bone marrow and differentiate into resident macrophages and dendritic cells. In contrast, a distinct inflamed monocyte subset with a CD11b+CCR2highLy-6ChighCX3CR1low phenotype infiltrates infected tissue and contributes to the development of inflammation. Currently, all studies performed with monocytes are done in transgenic models (i.e. CCR2-/-; GPF-CX3CR1 models) or with expensive techniques to study and acquire the maximum number of cell possible from mice blood. Monocytes constitute around 2% (100cells/μl) of the total peripheral blood leukocyte pool in mice, where only 1-5% are Ly-6Chigh monocytes. What makes difficult to study it. b. Objective 1. Development of an in vitro model that allow the generation of large amounts of Ly-6Chigh monocytes from bone marrow from mice. 2. Characterization of the phenotype of Ly-6Chigh monocyte generated in vitro. 3. Analyze the activation function of Ly-6Chigh monocyte generated in vitro. 4. Study the migration of Ly-6Chigh monocytes in to two inflammation models: - Skin (DNFB model) - Muscle (Notexin muscle model) 5. Analyze the therapeutic effect of Ly-6ChighCD11b+ monocytes injection in the resolution of inflammation in two experimental models of inflammation. c. Methodology and Results To achieve the first aim of our work, bone marrow cells were cultured with different grows factors and FCS at 37ºC in a humidified 5% CO2 atmosphere for 7 days when the population of floating cells was obtained and stained with Ly-6C and CD11b markers. This population was sorted for the acquirement of the Ly-6ChighCD11b+ cells. In order to characterize the phenotype of these cells we stained them with several markers. Our results demonstrated that this Ly-6Chigh enriched population is CD11b+CD62L+CCR2+ F4/80+CX3CR1low, presenting the same phenotype of the cells presents in the blood. To study the functional heterogeneity of enriched Ly-6Chigh cells, these cells were incubated with IFN-γ as typical classical stimuli and IL-4 as an alternative pathway stimulus. Ly-6Chigh cells incubated with IFN induced the expression of TNF and NOS2 with a characterized kinetics similar to macrophages. However, these cells increased arginase-1 levels when were stimulated with IL-4. Thus, the in vitro results have shown the plasticity and heterogeneity of monocytes as previously described by macrophages and thus, suggests us that these cells can also adapt to changing microenvironments as previously described. Further, to observe the migration capacity and functionality of these cells in vivo, we optimized two experimental model of inflammation. In the first model an ear skin irritation with 1%DNFB was induced. In the second model, muscle inflammation was developed by the injection of Notexin in the tibialis anterioris. In both models inflammation was induced and Ly-6Chigh enriched cells stained with an infrared fluorocrome were injected intravenous in mice and migration was observed by in vivo image at different days. Migratory capacity of Ly-6C cells to the inflamed tissues was appreciated in both models, corroborating with data previously described. To analyze the therapeutic effect of Ly-6ChighCD11b+ monocytes injection in the resolution of inflammation, RNA and histology cuts were obtained from both models. The results showed that Ly-6Chigh-injected mice express higher levels of anti-inflammatory genes such as mannose receptor, which corroborate with the histological images where animals treated with Ly-6Chigh cells recover before of the inflammatory process that untreated animals. d. Conclusion 1. We established a novel in vitro protocol to generate Ly-6ChighCD11b+ monocyte obtained from bone marrow of Balb/C mice. 2. The cells generated in vitro have the same phenotype of the Ly-6C from blood flow. 3. Cells Ly-6ChighCD11b+ monocyte present high plasticyty. 4. Ly-6ChighCD11b+ monocytes generated in vitro migrate in vivo. 5. Injection in acute and chronic in vivo inflammatory models of Ly-6ChighCD11b+ monocytes generated in vitro, display an improvement in the site of inflammation through the presentation of a more anti-inflammatory profile. / Monocitos circulantes proporcionan una defensa contra las infecciones y también a enfermedades autoinmunes. Recientemente dos tipos de monocitos fueran identificaron en la sangre periférica de ratones. El monocito ¿residente¿ con fenotipo CD11b+CCR2lowLy-6ClowCX3CR1high, que migran a tejidos no lesionados y se diferencian en macrófagos residentes y células dendríticas (DC). En contraste, un subconjunto distinto conocido como monocitos ¿inflamatorios¿, con un fenotipo CD11b+CCR2highLy-6ChighCX3CR1low son células que migran al tejido infectado y en lo cual contribuye al desarrollo de la inflamación. Monocitos Ly-6Chigh, el objetivo de nuestro trabajo, representan un 2-5% de los monocitos del torrente sanguínea de los ratones. Dado que estas células son de difícil obtención y que la cantidad obtenida de la sangre de ratones es muy baja, nuestro grupo desarrolló un nuevo sistema para generar monocitos Ly-6Chigh in vitro a partir de médula ósea de ratón, con el objetivo de estudiar sus funciones in vivo en dos modelos animales de inflamación. Nuestro laboratorio ha optimizado dos modelos animales capaces de inducir inflamación local en ratones Balb/c, inmunocompetentes. En el primer modelo, 1-fluoro-2 ,4-dinitrobenceno (DNFB) se aplicó tópicamente en la oreja derecha para crear en la piel condiciones que inducen la migración de estas células para el sitio de la irritación (modelo DNFB). En este modelo de piel, la inflamación en la oreja fue calculada atreves del peso neto, donde el peso de la oreja izquierda es restado del peso de la oreja derecha después de 24h y 48h de la inyección intravenosa (iv) de los monocitos Ly-6ChighCD11b+ en los ratones. En el segundo modelo, la inflamación es inducida atreves de la aplicación de una inyección de Notexin en el tibial anterior (TA) de la pierna derecha del animal la cual induce una inflamación muscular (modelo Notexin). Finalmente en ambos modelos, monocitos Ly-6ChighCD11b+ generados in vitro pre-tratados in vitro con citocinas pro- o anti-inflamatoria (IFN-¿ o IL-4) o no tratados, fueran inyectados iv en la colas de los ratones. Por otra parte, expresión génica fue medida mediante PCR cuantitativa en tiempo real, la migración celular fue evaluada in vivo atreves de imágenes realizadas por el equipo de IVIS, estudios de citometría de flujo y ensayos de histología también fueran realizados para evaluar la función de las células Ly-6Chigh en el sitio de inflamación. El principal objetivo de nuestro estudio es: 1. Desarrollo de un modelo in vitro que permita generar grandes cantidades de monocitos Ly-6Chigh a partir de médula ósea de ratones. 2. Caracterización del fenotipo de los monocitos Ly-6Chigh generados in vitro. 3. Analizar funciones de los monocitos Ly-6Chigh generados in vitro tras su activación in vitro. 4. Estudio de la capacidad migratoria de los monocitos Ly-6Chigh generados in vitro en dos modelos de inflamación. - Piel (modelo de DNFB en oreja). - Músculo (modelo Notexin muscular). 5. Analizar el efecto terapéutico de la inyección de monocitos Ly-6Chigh generados in vitro en la resolución de la inflamación en dos modelos experimentales de inflamación. En ambos modelos animales la inflamación local aumentó en función del número de monocitos Ly-6Chigh inyectados. Migración celular fue analizada por imágenes in vivo en ambos modelos, donde células Ly-6Chigh generated in vitro fluorescentes estaban presentes apenas en el tejido inflamado. Análisis de hematoxilina y eosina en cortes histológicos demostraron una mejoría del tejido de los animales tratados con monocitos Ly6Chigh. En resumen, los resultados obtenidos en esta Tesis Doctoral revelar un nuevo método para generar in vitro Ly-6Chigh monocitos de médula ósea de ratones, con una mejora en la eficiencia de la producción celular, que facilitan el estudio de estas células in vitro e in vivo. Además, también han demostrado la capacidad de las células Ly-6Chigh para cambiar el fenotipo de la estimulación in vitro verdadera y la capacidad de migrar, así como la heterogeneidad funcional en dos modelos de inflamación in vivo, lo que indica que estas células accionar de la misma manera como se las células proveniente de la sangre periférica. Además, hemos demostrado que Ly-6Chigh monocitos pueden ser pre-tratados con citoquinas en orther para retrasar o aumentar la reparación de tejidos (IFN-¿ o IL-4), respectivamente Todos estos resultados juntos sugieren que los monocitos Ly-6Chigh generado por nosotros in vitro son células funcionales que se pueden utilizar como una herramienta terapéutica para tratar enfermedades inflamatorias.
317

Contribució a l'estudi de l'efecte del canvi d'escala en l'experimentació en incendis forestals

Pérez Ramírez, Yolanda 20 May 2010 (has links)
Any rere any milions d'hectàrees són destruïdes pels incendis forestals, no només a Europa sinó arreu del món, tan sols cal recordar els dramàtics episodis viscuts a Califòrnia i Austràlia recentment. A banda de l'evident impacte mediambiental que això provoca -emissió de gasos d'efecte hivernacle, pèrdua de biodiversitat, acceleració de l'erosió del sòl, etc.- els incendis són també un problema social de primer ordre, que posa en perill a les persones i els seus béns. Davant d'aquesta situació, en les darreres dècades s'ha impulsat fortament la recerca en l'àmbit dels incendis forestals. Tanmateix, l'estudi dels incendis forestals és certament complex per les condicions i l'entorn on aquests es desenvolupen, a banda també del gran nombre de fenòmens -físics, químics i socials- que interaccionen al llarg de diferents escales espacials i temporals, per a donar lloc a l'inici i propagació del foc. És per això que bona part de la recerca sobre el comportament dels incendis forestals ha tingut lloc bàsicament al laboratori, tot i que qüestions com ara com traslladar aquests resultats experimentals als incendis reals, o bé fins a quin punt aquest tipus d'experimentació és útil o què és el que realment es pot extrapolar i què no, no han tingut encara cap resposta clara.L'objectiu d'aquesta tesi ha estat doncs el de contribuir a l'estudi del canvi d'escala en l'experimentació en incendis forestals pel què fa al comportament del foc, mitjançant les tècniques de l'anàlisi dimensional i de semblança. En primer lloc s'ha realitzat una extensa revisió bibliogràfica centrada bàsicament en aquells treballs que havien aplicat d'alguna manera o altra l'anàlisi dimensional i de semblança a l'estudi dels incendis i en particular dels incendis forestals. S'ha vist que no es possible realitzar un escalatge complet d'aquest fenomen i que el més utilitzat ha estat l'escalatge de Froude. A més s'ha detectat que mai abans s'ha aplicat aquest tipus d'anàlisi als models que s'utilitzen normalment avui dia en l'experimentació de laboratori. A continuació s'ha fet doncs una anàlisi exhaustiva de totes les variables que determinen el comportament d'un incendi forestal en els diferents escenaris experimentals (de laboratori i de camp). A partir d'aquestes variables s'ha realitzat una anàlisi dimensional per a estudiar la propagació d'un front de flames -tan bàsic com en condicions de vent i pendent- així com una anàlisi de semblança que ha permès obtenir les lleis d'escala per a les diferents variables que caracteritzen la propagació d'un incendi forestal. S'ha dissenyat i executat un programa experimental al laboratori amb l'objectiu de validar si es complien les lleis d'escala trobades i de determinar-ne el rang de validesa i les possibles causes en cas que no es complissin.Els resultats obtinguts han mostrat que per a fronts de flama bàsics propagant-se sense vent ni pendent, totes les variables analitzades segueixen les lleis d'escala derivades de l'estudi teòric, en el rang de longituds de front de flama abraçat que va dels 25 cm als 3 m. Nogensmenys cal remarcar que paràmetres com la humitat i el tipus de combustible o les característiques de la instal·lació experimental utilitzada poden alterar enormement els resultats si no es controlen adequadament. En el cas dels fronts de flama propagant pendent amunt, els resultats han mostrat que les lleis d'escala de la geometria de flama es compleixen per a tot el rang de pendents estudiat que va de 0 fins a 30°, mentre que en el cas de la llei d'escala de la velocitat de propagació deixa de complir-se per a pendents de 30°. Finalment, en el cas dels fronts de flama propagant en condicions de vent, els resultats han mostrat que per a velocitats del vent superiors a aproximadament 2,5 m/s les lleis d'escala tant de la velocitat de propagació com de la geometria de flama deixen de complir-se.Al final d'aquest treball s'apunten les causes que poden conduir a l'incompliment de les lleis d'escala així com als factors que poden restar validesa als experiments efectuats a escala de laboratori, quan es vol extrapolar els resultats a escales més grans o fins i tot a incendis reals. / Year after year millions of hectares are destroyed by wildland fires, not only in Europe but all over the world; just remember the dramatic episodes recently occurred in California or Australia. Besides the evident environmental impact caused by these fires -emission of greenhouse gases, biodiversity loss, soil erosion, etc- wildland fires represent also a social problem of primary order that threatens human life and their assets.Because of this situation, during the last decades research on wildland fires has been greatly boosted. Nevertheless, the study of forest fires is really complex due to the conditions and the environment in which they develop and to the number of phenomena -physical, chemical and social- that interact all along the different spatial and temporal scales that give rise to the start and development of a fire. That is partly the reason because the study of wildland fire behaviour has mainly been developed in laboratories, but questions like how these experimental results can be translated to real fires?, or is really this kind of experimentation useful?, or what can be extrapolated? These questions have not yet received a clear answer.The goal of this work was to improve the knowledge on the effect of changing the scale in the experimental study of forest fire behaviour, by means of dimensional and similarity analysis. First an extended bibliographic review has been done, centred on those works that had applied in one or another way the dimensional and similarity analysis to the study of fires and more specifically to forest fires. It was observed that it is not possible to undergo a complete scaling of a forest fire and that the most used partial scaling technique was the Froude scaling. Moreover it was detected that this kind of analysis was never before applied to the laboratory models used currently to obtain experimental data on wildland fires. Thus, an exhaustive analysis of all the variables affecting forest fire behaviour has been carried out for the diverse experimental scenario (in the lab and field). From these variables, a complete dimensional analysis has been developed in order to study the spread of a flames front -both in basic conditions and with slop or wind- and a subsequent similarity analysis has provided the scaling laws governing all the variables under study. A complete experimental program has been designed and developed in the laboratory with the aim of validating the scaling laws previously found and to establish the possible causes of any failure of the laws. The results obtained show that in the case of a basic flame front, spreading under no wind and no slope conditions, all the variables analysed followed the scaling laws obtained during the theoretical study for flames front lengths ranging from 25 cm to 3 m. For the tests under slop conditions, the results indicate that the scaling laws corresponding to the flame geometry are verified for all the slopes tested which range from 0 to 30°, while in the case of the rate of spread scaling law is no longer verified for the 30° slope. Finally, in the case of flame fronts spreading under wind conditions, the results show that for wind speed values greater than 2,5 m/s neither of the scaling laws corresponding to the flame geometry and the rate of spread, are verified. It has also been observed that parameters such as moisture content, the type of fuel or the specific design of the experimental device used can have a big influence on the results obtained if they are not adequately controlled.At the end of this work, the main causes leading to the failure of the scaling laws are pointed out together with the factors that can make the laboratory experiments less reliable when trying to extrapolate the results to larger scales or even to real fires.
318

Human research participant protections : a rhetorical analysis of two key documents /

Ballance, Lisa R. January 2001 (has links) (PDF)
Thesis (M.A.)--Old Dominion University, 2001. / Includes bibliographical references.
319

Comportement biomécanique de la paroi abdominale et de ses composants musculaires : du specimen isolé au patient

TRAN, Doris 10 December 2013 (has links) (PDF)
Dans le but d’améliorer le traitement des éventrations, cette thèse porte sur la biomécanique de la paroi abdominale. Plusieurs aspects de son comportement ont été étudiés: de la paroi globale aux constituants, de la paroi passive ex vivo sous chargement contrôlé à la paroi active in vivo sous chargement physiologique et enfin de la paroi saine des volontaires non-malades à la paroi lésée des patients en pré-opératoire. Un protocole a été développé pour évaluer la contribution des composants de la paroi abdominale humaine ex vivo à sa réponse mécanique globale. Les spécimens sont sollicités par pression après dissection successive des différents composants. L’analyse par stéréo-corrélation des déformations de la surface interne a montré que la gaine des rectus abdominis joue un rôle important dans la réponse de la paroi abdominale antérieure. Les examens in vivo ont permis de considérer la paroi abdominale in situ de 11 volontaires non-malades et pour la première fois de patients souffrant d’éventration (n=4) en pré-opératoire. Géométrie externe et interne, élasticité des muscles et raideurs locales ont été mesurées lors d’activités physiologiques. Les paramètres mécaniques mesurés sur les patients restent soit dans l’étendue de mesure des valeurs des volontaires non malades, soit sont plus faibles. Dans le futur, l’inclusion d’autres patients et des examens post-opératoires seront poursuivis. On disposera alors de données quantitatives de la paroi abdominale couvrant l’état sain, lésé et réparé. Des modèles numériques pourront être développés. Ils permettront d’estimer l’influence de paramètres mécaniques et géométriques sur le comportement de la paroi abdominale.
320

Reducing remodularization complexity through modular-objective decoupling

Chern, Rick 11 1900 (has links)
This dissertation defines "modular-objective coupling", and shows that programming language designs which imply reduced modular-objective coupling reduce complexity of remodularizations--behaviour-preserving restructurings for which the only intended goals are to change program source code structure. We explicitly distinguish between two points of view on program structure: modular structure--the structure of a program as a set of static text documents, and objective structure--the structure of a program as a dynamic computational model during execution. We define modular-objective coupling as the degree to which changes in modular structure imply changes to objective structure, for a given programming language. We use the term remodularization to refer to any behaviour-preserving source code restructuring, for which the only intended goal is to change modular structure. We argue that programming languages with strong modular-objective coupling introduce accidental complexity into remodularizations, by requiring complex objective structure changes to achieve intended modular structure changes. Our claim is that a programming language design which implies reduced modular-objective coupling reduces remodularization complexity in the language. To validate this claim, we first present SubjectJ, a subject-oriented programming system that extends Java. The design of Java implies strong modular-objective coupling, while SubjectJ is designed for reduced modular-objective coupling. We then perform a series of remodularization case studies comparing Java and SubjectJ. Our results suggest that remodularizations are less complex in SubjectJ.

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