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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.
11

"Det är inte mig det är fel på, det är huset" : en studie av prognosfaktorer och bemötande med fokus på sjuka hus-syndromet / “Now enough is enough, it's not me that`s wrong it's the house”. : A study of factors for prognosis and encounter focusing on sick building syndrome

Edvardsson, Berit January 2015 (has links)
Bakgrund: Sick Building Syndrome, SBS, är fortfarande 2015 ett tillstånd som vållar mycket diskussion. Symtomen kan grupperas i slemhinnesymtom, hudsymtom och allmänna symtom. I definitionen ingår att personen/ personerna som fått symtom har exponerats för dålig inomhusluft i en speciell byggnad. När personen inte är i byggnaden så förbättras eller försvinner symtomen. Många olika faktorer kan orsaka eller medverka till uppkomst eller försämringar av SBS-symtom, som t.ex. luftens innehåll av olika ämnen, luftflöden, temperatur, buller, fukt och mögel. Utbredd enighet finns om att fukt och mögel i byggnaderna påverkar eller ger upphov till symtom hos vissa personer som exponeras där. Psykosociala faktorer som arbetets organisation och krav och individuella faktorer som kön och personlighet påverkar också. Syfte: Hypotesen är att faktorer som tidigare hälsa, åtgärder på arbetet, tid, behandling, personlighet och copingresurser alla kan påverka prognosen för SBS-patienterna. Syftet med avhandlingen är att undersöka hur symtomen påverkar arbetsförmågan och om patienterna återhämtar sig från SBS-symtomen. Ett annat syfte är att undersöka bemötande och de erfarenheter som SBS-symtomen gett en grupp av informanter med SBS. För att förstå om personlighet mätt med självbild och coping hade någon betydelse för progressionen av SBS-symtom och arbetsförmåga gjordes jämförelser av personlighet mellan en patientgrupp med SBS, en patientgrupp med handeksem, en patientgrupp med elkänslighet och en normalpopulation. Metod:  En uppföljningsenkät skickades till 239 patienter med SBS-symtom som under åren 1986–1998 blivit undersökta och bedömda på Universitets-sjukhuset i Umeå, Sverige. Frågorna innehöll social och medicinsk status, nuvarande symtom, behandlingar, åtgärder på arbetsplatsen, coping och självbild och svarsfrekvensen var 79,1%. Prognos och riskfaktorer för prognos beräknades för SBS-patienterna. Mätningar av personlighetsfaktorer gjordes med instrumentet Structural analysis of Social Behaviour, SASB, och coping mättes med Coping Resources Inventory, CRI. Likadana uppföljningsenkäter skickades till en grupp patienter med handeksem och patienter med upplevd elkänslighet. Svarsfrekvensen var 68% respektive 73% och enkätsvaren har sedan analyserats och jämförts genom beräknngar av prognos med fokus på självbild och coping för SBS-patienterna och handeksempatienterna. Jämförelser gjordes också mellan de tre olika grupperna och en kontrollgrupp vad gäller självbild och coping. För att undersöka erfarenheterna av SBS-symtomen och bemötandet genomfördes kvalitativa intervjuer med 10 informanter som hade eller hade haft SBS-symtom. Fem av dem hade diagnostiserats en längre tid tillbaka medan de andra fem hade haft SBS-symtomen en kortare period. Semi-strukturerade intervjuformulär användes vid intervjuerna och anlyserades med kvalitativ innehållsanalys. Resultat: Graden och svårigheten av SBS-symtomen minskade över tid trots att nästan hälften av SBS-patienterna beskrev att symtomen var mer eller mindre oförändrade efter 7 år eller mer. Risken att ha symtom vid uppföljningen var större för de patienter som remitterats sent efter symtomdebut men även för de som hade kort uppföljningstid. Risken att inte ha någon arbetsförmåga vid uppföljningen var signifikant ökad om det var mer än ett års skillnad mellan symtomdebut och första läkarbesöket p.g.a. SBS-symtomen eller om patienten vid första undersökningen hade fler än 5 SBS-symtom. Dagliga aktiviteter som t.ex. bussåkning förvärrade också symtomen för patienterna. Informanternas upplevelser av SBS-symtomen från början visar en influensaliknande bild med rinnande näsa och ögon, heshet, hosta och huvudvärk. Informanterna agerar för att klara av situationen när symtomen förvärras. Genom hela processen upplever de en brist på bekräftelse och stöd från arbetsgivare, primärvård, företagshälsovård och fastighetsförvaltare. Alla tre patientgrupperna hade högre värden i spontan och positiv självbild i jämförelse med en kontrollgrupp. De hade också alla lägre värden i kontroll medan patienterna med handeksem och de med elkänslighet hade högre värden i sin negativa självbild. När det gäller coping skilde sig inte patientgrupperna från kontrollgruppen utom i CRI kognitiv där SBS-patienterna hade hög poäng i motsats till handeksempatienterna som hade låg poäng i samma domän. De elkänsliga patienterna hade i stället höga poäng i domänen andlig/filosofisk. Självbild eller copingförmåga var inte associerade med SBS-symtom eller symtom av handeksem vid uppföljningen och deras personlighet påverkade inte arbetsförmågan. Tidigare atopisk dermatit var en signifikant risk för kvarvarande symtom men inte för arbetsförmågan hos handeksempatienterna. Slutsats: En grupp av patienter som tidigare diagnostiserats för symtom från inomhusmiljön har kroniska symtom och påverkan på sitt sociala liv. Över tid minskar symtomen. Resultaten pekar på att ett tidigt omhändertagande är av vikt. SBS-symtomen är från början svåra att upptäcka för alla inblandade och kunskap om hur symtomen kan uppstå i dagligt liv kan bidra till bredare förståelse. Erfarenheterna från personer med SBS visar på avsaknad av bekräftelse och stöd från vården, företagshälsan, arbetsgivare och fastighetsförvaltare. Sambandet mellan symtom och inomhusmiljö får inte glömmas bort. Stöd och bekräftelse innebär också kunskap om skyldigheter för arbetsgivare och fastighetsförvaltare. Skillnad i självbild i jämförelse med en kontrollgrupp ses hos patientgrupperna med symtom som är delvis oförklarade men också hos handeksempatienter med ett väletablerat tillstånd. Det kan innebära att patienter med kroniska tillstånd överlag kan avvika från den allmänna populationen. Patienterna visar som grupp en hög positiv och hög spontan självbild som kan leda till svårigheter att sätta gränser. Detta kan leda till en mental stress och i förlängningen också ge en ökad känslighet/sårbarhet för miljöfaktorer. / Background: Sick Building Syndrome (SBS) is still in 2015 a controversial condition. The set of non-specific symptoms occurring in a particular building and not caused by specific illness such as allergy or infection are questioned. The variousSBS symptoms can be grouped as dermal, mucosal and general and there is no universally accepted clinical definition of SBS. Symptoms normally improve or disappear when people are not exposed in a particular building. SBS is a multifactorial disease and described as a syndrome caused or aggravated by many factors related to indoor environment such as dampness and mould, insufficiency of fresh air, but also psychosocial and individual factors like female gender and personality. Objectives: The hypothesis is that personal factors such as previous health, actions taken, time, treatment, personality and coping resources are factors important in influencing the prognosis for SBS patients. The main purpose of this thesis is to explore more about how the symptoms affect work-capability and if SBS patients recover from their symptoms. Another important aim is to explore the experience of the emergence of symptoms and encounters in a group of people with SBS. To find out more about personality and coping resources and their importance for the progress of SBS symptoms comparisons were made with a selection from the general population, a group of patients having hand eczema and a group of patients with perceived sensitivity to electricity. Methods: A follow-up questionnaire focusing on current medical and social status, care, treatment, other measures taken, coping and personality traits was sent to 239 patients with non-specific building-related symptoms, assessed during the period between 1986-1998 at the University Hospital in Umeå, Sweden, response rate 79,1%. Prognosis and risk factors for prognosis were calculated for the SBS patients.  Measurement of personality traits like self-image was done using Structural analysis of Social Behaviour, SASB, and coping ability was measured with Coping Resources Inventory, CRI. Similar follow-up questionnaires for patient groups with hand eczema and perceived electrical sensitivity were used and response rates were 68% respectively 73%. Risk factors for prognosis with focus on self-image and coping were calculated for the SBS patients and the group of patients having hand eczema. Comparisons were made between self-image and coping among SBS patients, patients with electrical hypersensitivity, patients with hand eczema and a selection from the general population. To explore the experience of SBS symptoms and encounters a semi-structured interview was performed with 10 informants with symptoms of SBS. Five of them were previously diagnosed and had participated in the earlier follow-up study. The remaining five had had SBS symptoms for a shorter period. The interviews were analysed using qualitative content analysis.    Results: The degree and severity of SBS symptoms decreased over time, although nearly half of the SBS patients claimed that symptoms were more or less unchanged after 7 years or more. The risk of having no work capabilities was significantly increased at follow-up if the time from debut to first visit at the hospital clinic was more than one year and this risk was also significantly higher if the patient at the first visit had 5 or more symptoms. Common daily activities, like going by bus, also aggravated the SBS symptoms according to answers in the questionnaires. The informants’ experiences of the emerging SBS symptoms are that when they first appear they are often similar to those of flu like runny nose and eyes, hoarseness, cough, and headache. Many of the informants act to change the way they manage the situation as a result of increased symptoms. During this whole process the informants/patients perceived a lack of confirmation and support from e.g. employers, primary health care and occupational health care centres. Regarding self-image, all three patient groups scored higher on spontaneous and positive self-image than a comparison group. They were all less controlled. The patients with hand-eczema together with the patients with perceived electrical sensitivity also had a high score on negative self-image. CRI- domains did not differ between patients and comparison group except on CRI cognitive, were the hand eczema patients had a lower score than the comparison group contrary to SBS patients who had a higher score than the comparison group. The patients with perceived electrical sensitivity had a higher score on CRI spiritual. Self-image or coping ability was not associated with SBS symptoms or persistent hand eczema symptoms at follow-up and their personality did not affect their work capability. Previous atopic dermatitis was the only consistent predictor of hand eczema at follow-up. Conclusion: Within this group of SBS patients there are long lasting symptoms aggravated by environmental factors. The results support that early and comprehensive measures for rehabilitation are essential for these patients. In the beginning the symptoms of SBS are diffuse and difficult to recognise for all involved. Patients with SBS symptoms experience a lack of confirmation and support. It is important that healthcare personnel confirm the patient and are aware of the possible connection between symptoms and the indoor environment. For employers and facility managers knowledge of their obligations in terms of working environment is important. Differences in personality traits were seen in a well-established condition and not only in patients with medically unexplained symptoms. This can imply that patients with general chronic symptoms can deviate from the general population with respect to self-image and coping ability. Certain personality traits may be potential risk factors that increase the probability of encountering and experiencing stressful work situations.
12

Desarrollo de films delgados a partir de copolímeros bloque con morfología controlada

Passaretti, María Gabriela 26 March 2019 (has links)
Un material compuesto es un material que se forma por la mezcla de dos o más materiales con propiedades diferentes entre sí, que al combinarse producen un nuevo material con propiedades distintas al de sus componentes individuales. En los materiales particulados, el componente mayoritario se conoce como matriz y el minoritario como relleno. El interés industrial por los materiales compuestos a base de matrices termoplásticas se debe principalmente a la versatilidad de usos y aplicaciones que presentan. Los rellenos (o cargas) de mayor interés comercial son los de origen mineral debido, principalmente, a su relativo bajo costo y alta disponibilidad, dando lugar al desarrollo de nuevos materiales compuestos de un costo relativamente bajo. Utilizando diferentes polímeros como matriz y distintos rellenos se pueden modificar las propiedades ópticas, térmicas, de barrera, mecánicas, etc., y, de esta forma, diseñar materiales compuestos “a medida” para distintas aplicaciones específicas. La correcta dispersión de las partículas de relleno depende en gran medida de la compatibilidad entre el polímero y la carga, y también de los métodos empleados para su obtención y procesamiento. Algunos de los métodos más utilizados son el mezclado en fundido, en solución o una combinación de ambos. Por otro lado, durante las últimas décadas ha crecido el interés por el desarrollo de materiales poliméricos con fuerte anisotropía en sus propiedades eléctricas, magnéticas, mecánicas, ópticas, de transporte o térmicas para su uso en variadas aplicaciones, tales como sensores y actuadores, prótesis óseas, electrónica, fotónica y membranas, entre otros. Los copolímeros bloque resultan de particular interés debido a los diversos arreglos macroscópicos que presentan, permitiendo un control sobre la distribución y orientación de las cargas. En esta tesis se desarrollaron películas de materiales compuestos a base de diferentes matrices poliméricas termoplásticas utilizando dos tecnologías de procesamiento. Para modificar las propiedades de las películas desarrolladas, se incorporaron diferente tipo de cargas. La aplicación posterior de flujos de corte y tratamientos térmicos mejoro aún más la estructura interna de largo alcance y las propiedades finales de los compuestos. Las películas obtenidas se caracterizaron mediante técnicas complementarias de análisis para estudiar la morfología y determinar las propiedades finales. Los resultados obtenidos mostraron que los materiales desarrollados orientados se pueden proponer como membranas selectivas para remoción de nitrógeno de corrientes de gas natural y remoción de dióxido de carbono post combustión. En cuanto a las películas compuestas obtenidas por mezclado en fundido y termo-compresión, se comprobó su capacidad de barrera a la radiación UV, protegiendo aguas saborizadas susceptibles a este tipo de radiación. / A composite material is a material obtained from combining two or more constituent material with different properties between them that, when combined produce a new material with different properties from the individual components. In the case of particulate composites, the component with higher concentration is known as the matrix while the one with lower concentration is the filler. The industrial interest for composite material based on thermoplastic matrices is mainly due to the versatility of the material, in relation to its uses and applications. The fillers (or charges) of high commercial interest are those of mineral origin, mainly owing to its relative low cost and high availability, resulting in the development of new relatively low cost composite materials. Using different polymer as matrix and different fillers, it is possible to modify the material (optical, thermal, barrier and mechanical, etc) properties and thus, design tailored composite materials for different specific applications. The correct dispersion of the filler particles largely depends in the compatibility between the polymer matrix and the filler particles, and also on the methods used to obtain and Process the composite material. Some of the most used methods are the melt mixing, solution mixing or a combination of both. Moreover, the interest for developing polymeric materials with strong anisotropy on its (electric, magnetic, mechanical, optical, transport or thermal) properties has greatly increased in the last decades due to its potential use on various applications like: sensors, and actuators, bone prosthesis, membranes and other uses in the fields of electronics and photonics. Block copolymers are of particular interest due to the multiple macroscopic arrangements that they can feature, which allows controlling the distribution and orientation of the fillers. In this thesis, composite material films were developed, using different thermoplastic polymeric matrices and two processing technologies. In order to modify the properties of the films, different kind of filler were introduced. The subsequent application of shear flows and thermal treatments further improved the long range internal structure and final properties of the composites. The films were characterized through complementary analysis techniques in order to study the morphology and determine its final properties. The results showed that the developed oriented material can be proposed to be used as selective membranes for nitrogen removal from natural gas streams and carbon dioxide removal post-combustion. Regarding the composite films obtained from melt mixing and thermo compression, its UV radiation barrier capacity was proved, which was tested for the protection of flavored water sensitive to this type of radiation.
13

Byggnadsrelaterad ohälsa och psykiskt lidande

Gustafsson, Astrid, Lahti, Sara January 2019 (has links)
Byggnadsrelaterad ohälsa (BRO) är ett tillstånd som utgörs av en intolerans för vissa byggnader eller delar av byggnader som yttrar sig genom besvärande ospecifika symtom. I tidigare studier har psykisk ohälsa visat sig vara en riskfaktor för BRO men det finns ännu få studier som undersöker detta. Syftet med den här studien var att undersöka hur utbrändhet, depression, ångest och stress, definierat som psykiskt lidande, ser ut hos personer med olika svårighetsgrader av BRO. Svårighetsgrad av BRO definieras på två sätt. Dels utifrån hur många symtomgrupper (fördelade i; slemhinne-, hud- och allmänsymtom) deltagarnas symtom ingår i. Dels utifrån hur stora besvär av BRO-symtomen deltagarna skattar att de har. Studien var en enkätstudie med 106 deltagare inklusive kontrollgrupp, rekryterade från sin företagshälsovård och arbetsplats. Deltagarna arbetade på Norrlands Universitetssjukhus i Umeå eller Skellefteå lasarett. Resultatet visade att det var signifikant fler i gruppen med svår BRO som uppnådde gränsvärdet för svår utbrändhet (4.47). Gruppen med svår BRO skattade signifikant högre än samtliga andra grupper gällande utbrändhet och signifikant högre än kontrollgruppen gällande depression. Alla delar av psykiskt lidande hade signifikanta positiva korrelationer med intensitet av besvär av BRO-symtom. Resultaten indikerar att psykiskt lidande, i synnerhet utbrändhet och till viss del depression, är associerat till stigande svårighetsgrad av BRO. / Building related intolerance (BRI) is a condition with disturbing and unspecified symptoms attributed to certain buildings or parts of buildings. In previous research mental ill-health has been identified as a risk factor for BRI, but the studies investigating this are still few. The general aim of the current study was to investigate how burnout, depression, anxiety and stress, defined as psychological distress, is constituted among people with different levels of severity of BRI. Level of severity was defined in two different ways. As number of BRI-symptoms (distributed into three groups; mucosal, skin and general symptoms) and as intensity ratings of suffering from BRI-symptoms. The data was collected through a questionnaire answered by 106 participants including a control group. Participants were recruited from their occupational health care and their workplace. The participants worked at the university hospital of Umeå or the hospital in Skellefteå. The results showed that there were significantly more people that reached a cut-off for severe burnout (4.47), in the group with severe BRI. The group with severe BRI rated significantly higher than all other groups regarding burnout and significantly higher than a control group regarding depression. All parts of psychological distress had a significant positive correlation with measures of suffering from BRI-symptoms. The results indicates that psychological distress, burnout in particular and partially depression, is associated with increasing severity levels of BRI.
14

Avaliação do desempenho em laboratório de misturas asfálticas densas utilizando asfalto convencional (CAP-20) e asfalto modificado com polímero SBS (BETUFLEX B 65/60) / not available

Taira, Claudio 27 April 2001 (has links)
Este trabalho teve por objetivo o desempenho de misturas asfálticas densas utilizando um ligante convencional (CAP-20) e o mesmo ligante modificado com polímeros tipo SBS, produzido sob o nome comercial de BETUFLEX B 65/60, através dos ensaios Marshall, fluência por compressão uniaxial estática e dinâmica, resistência à tração por compressão diametral e módulo resiliente pro compressão diametral dinâmica, em misturas compactadas com uma mesma faixa granulométrica e diferentes teores de ligantes. O ensaio Marshall apresentou, para as misturas preparadas com asfalto modificado, valores maiores de estabilidade para a maioria dos teores, apesar de valores elevados de fluência em todos os teores analisados. Os resultados de deformação do ensaio de fluência por compressão uniaxial não distinguiram claramente o efeito da adição de polímeros em misturas asfálticas, ao contrário do observado no ensaio dinâmico, onde as deformações foram consideravelmente menores para a maioria dos teores analisados. Os resultados do ensaio de resistência à tração por compressão diametral mostram um desempenho superior da mistura modificada. O ensaio de módulo resiliente por compressão diametral dinâmica indicou, à temperatura de 25ºC, valores menores para a mistura com asfalto modificado, não sendo notada, entretanto, uma diferenciação de desempenho nas temperaturas de 5ºC e 40ºC. A modelação matemática das curvas de fluência e de recuperação às equações constitutivas de alguns modelos visco-elásticos básicos detectou uma diferenciação entre os valores de alguns elementos constitutivos, tanto do ensaio dinâmico, quanto do estático. / The purpose of this study is to evaluate the performance of asphalt mixes using conventional binder and the same binder modified with SBS polymer (Betuflex B 65/60) based on Marshall test, static and dynamic creep tests, indirect tensile strength test and resilient modulus by indirect tensile test, with the same granulometric composition and different binders contents. In Marshall test, polymer modified asphalt mixes presented better stability performance than conventional asphalt mixes in most of binders contents, despite of the higher flow values obtained for all binders contents. The static creep test results indicated that this test does not clearly distinguish the effect of polymer in asphalt mixes while the results of dynamic creep test indicated the opposite, i. e., polymer modified asphalt mixes deformations are smaller for most of the asphalt binders contents studied. The indirect tensile strength test results showed a better performance of modified asphalt. The results of resilient modulus by indirect tensile test at 25°C showed smaller values for modified asphalt, while the results at 5ºC and 40ºC did not show differences between the asphalt mixes. The mathematics modelling of the creep and recovering curves according to constitutive equations of some basic visco- elastic models showed a difference between the values of some constitutive elements in both cases, dynamic and static tests.
15

Avaliação do desempenho em laboratório de misturas asfálticas densas utilizando asfalto convencional (CAP-20) e asfalto modificado com polímero SBS (BETUFLEX B 65/60) / not available

Claudio Taira 27 April 2001 (has links)
Este trabalho teve por objetivo o desempenho de misturas asfálticas densas utilizando um ligante convencional (CAP-20) e o mesmo ligante modificado com polímeros tipo SBS, produzido sob o nome comercial de BETUFLEX B 65/60, através dos ensaios Marshall, fluência por compressão uniaxial estática e dinâmica, resistência à tração por compressão diametral e módulo resiliente pro compressão diametral dinâmica, em misturas compactadas com uma mesma faixa granulométrica e diferentes teores de ligantes. O ensaio Marshall apresentou, para as misturas preparadas com asfalto modificado, valores maiores de estabilidade para a maioria dos teores, apesar de valores elevados de fluência em todos os teores analisados. Os resultados de deformação do ensaio de fluência por compressão uniaxial não distinguiram claramente o efeito da adição de polímeros em misturas asfálticas, ao contrário do observado no ensaio dinâmico, onde as deformações foram consideravelmente menores para a maioria dos teores analisados. Os resultados do ensaio de resistência à tração por compressão diametral mostram um desempenho superior da mistura modificada. O ensaio de módulo resiliente por compressão diametral dinâmica indicou, à temperatura de 25ºC, valores menores para a mistura com asfalto modificado, não sendo notada, entretanto, uma diferenciação de desempenho nas temperaturas de 5ºC e 40ºC. A modelação matemática das curvas de fluência e de recuperação às equações constitutivas de alguns modelos visco-elásticos básicos detectou uma diferenciação entre os valores de alguns elementos constitutivos, tanto do ensaio dinâmico, quanto do estático. / The purpose of this study is to evaluate the performance of asphalt mixes using conventional binder and the same binder modified with SBS polymer (Betuflex B 65/60) based on Marshall test, static and dynamic creep tests, indirect tensile strength test and resilient modulus by indirect tensile test, with the same granulometric composition and different binders contents. In Marshall test, polymer modified asphalt mixes presented better stability performance than conventional asphalt mixes in most of binders contents, despite of the higher flow values obtained for all binders contents. The static creep test results indicated that this test does not clearly distinguish the effect of polymer in asphalt mixes while the results of dynamic creep test indicated the opposite, i. e., polymer modified asphalt mixes deformations are smaller for most of the asphalt binders contents studied. The indirect tensile strength test results showed a better performance of modified asphalt. The results of resilient modulus by indirect tensile test at 25°C showed smaller values for modified asphalt, while the results at 5ºC and 40ºC did not show differences between the asphalt mixes. The mathematics modelling of the creep and recovering curves according to constitutive equations of some basic visco- elastic models showed a difference between the values of some constitutive elements in both cases, dynamic and static tests.
16

O emprego de borracha termoplástica tipo estireno-butadieno-estireno em cimentos asfálticos de petróleo / The use of thermoplastic rubber type styrene-butadiene-styrene asphalt cements oil

Maciel, Emerson Rodrigues 17 August 2018 (has links)
Orientador: Wagner dos Santos Oliveira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-17T00:29:49Z (GMT). No. of bitstreams: 1 Maciel_EmersonRodrigues_M.pdf: 10298208 bytes, checksum: d19a140f86e923ce68500657b2e841fa (MD5) Previous issue date: 2010 / Resumo: Este trabalho apresenta resultados o estudo de pesquisa e desenvolvimento de misturas de polímeros em cimento asfáltico de petróleo. O asfalto é um excelente material aglutinante utilizado na construção de rodovias e vias urbanas, entretanto o aumento do número de veículos comerciais e da carga transportada por eixo tem levado a deteriorização prematura dos pavimentos. Os resultados obtidos mostram que o polímero do tipo estireno-butadieno-estireno quando incorporado ao asfalto traz melhoria nas propriedades físico-químicas e desempenho, sobretudo quando em contato com cargas pesadas, em climas quentes, tornando-o resistente à deformação permanente, pela preservação de sua flexibilidade e elasticidade. A incorporação de 4% polímero tipo estirenobutadieno-estireno ao asfalto resultou na melhoria de suas propriedades, principalmente a resistência ao envelhecimento, aumento no ponto de amolecimento, ganho de recuperação elástica. O asfalto modificado é uma boa solução, pois embora aumente os custos iniciais do produto, resulta em um ótimo custo benefício, reduzindo a necessidade de manutenção das rodovias ou vias urbanas ao longo dos anos / Abstract: This paper presents laboratorial research results comprising developing project of polymer mixtures in petroleum asphalt cement. The asphalt is an excellent binding material used in the highway constructions and unban roads, however the increase of the commercial vehicles number and the load transported by axle have led to the premature pavements failure. The laboratory outcomes obtained show that the SBS polymer, which is embedded to the asphalt, brings improvement in the physico - chemical properties and performance mainly for its good performance under heavy loads in hot climates becoming resistant to the permanent deformation, but maintaining the flexibility as the asphaltic concrete providing elasticity. The SBS polymer is a good solution, although it increases the initial costs of the product, however with a great costeffective regarding the maintenance of the highways or unban roads over the years / Mestrado / Ciencia e Tecnologia de Materiais / Mestre em Engenharia Química
17

Dynamic Performance-based Decision Support for Service Reusability / Aide à la décision dynamique basée sur les performances pour la réutilisation des services

Masood, Tehreem 26 October 2018 (has links)
La réutilisation des services pour prendre en charge de nouveaux processus métier, en plus de l'alignement de l'informatique sur les fonctions métier, constitue une motivation clé pour l'utilisation de l'architecture orientée services (SOA) pour le développement de solutions métier. Dans une architecture orientée services, il est important de faciliter la sélection, la configuration et la composition des services existants pour faire face aux changements d’exécution ou à l’évolution des besoins des utilisateurs finaux. Contrairement aux autres systèmes logiciels traditionnels, le comportement dynamique des systèmes basés sur les services nécessite des informations de qualité de service (QoS) actualisées pour assurer une gestion appropriée dans les différentes étapes du cycle de vie. Les entreprises doivent connaître les performances des services Web et des processus métier pour préserver leur pérennité en matière de réutilisation des services. Les trois principaux avantages de la réutilisation des services sont l'amélioration de l'agilité des solutions en assemblant rapidement de nouveaux processus métier à partir des services existants pour répondre aux besoins changeants du marché, réduire les coûts en ne développant pas de nouveaux services pour activer des fonctions métier similaires dans plusieurs processus métier, mais également le déploiement et la gestion des services dans les environnements d'exécution tout au long du cycle de vie SOA. Cependant, il existe actuellement de nombreux défis liés à la durabilité et à la gouvernance du comportement des services pendant son cycle de vie. Parmi ces défis, on peut citer le niveau de performance, la persistance des exigences et l'adaptabilité du service. De plus, il existe certaines limites des outils de surveillance. Ils manquent d’anticipation dans la détection des problèmes et ils sont passifs et ne sont ni réactifs ni prédictifs. Cette thèse porte sur l’évaluation et les recommandations en matière de performance et de gouvernance des systèmes d’information pour suggérer la réutilisation des services au cours de son évolution. L'objectif est de maintenir la durabilité, la robustesse, l'adaptabilité, la réutilisabilité et l'évolutivité des systèmes d'information. À cette fin, nous évaluons les performances de l'architecture orientée service. Il existe plusieurs solutions de surveillance existantes conçues pour prendre en charge une couche spécifique de SOA. En particulier, BAM est un outil de surveillance des activités commerciales permettant de surveiller le flux de données pour les processus métier. Cependant, la surveillance BAM ne fournit pas l'évaluation des performances pour recommander des services et des processus à réutiliser. Il existe très peu d'approches prenant en charge la surveillance des couches SOA. De plus, les solutions sont partiellement dynamiques avec une aide à la décision limitée. Par conséquent, nous proposons une aide à la décision basée sur la performance pour une architecture orientée services. Il se compose de quatre couches en tant que couches de spécification, de gestion des données, d'exploration de données et de décision. La couche de spécification identifie les exigences de l'utilisateur final et les traite via l'ontologie proposée. La couche de données analyse les indicateurs techniques conformes aux normes de qualité les plus récentes, ISO 25010. Les caractéristiques de qualité sont liées à l'efficacité des performances, à la fiabilité et à la réutilisation. La couche d'exploration de données génère des décisions spécifiques basées sur des instances de service en appliquant les algorithmes d'apprentissage automatique. Il utilise les concepts ontologiques proposés et les règles d'inférence sémantique du service, des processus métier, des couches serveur et d'intégration. La couche d'exploration de données renvoie aux ontologies avec ces décisions spécifiques où des règles plus raffinées ont été générées.... / Reuse of services in supporting new business processes, in addition to alignment of IT with business functions, is a key motivation in using Service-Oriented Architecture (SOA) for developing business solutions. In a service-oriented architecture, it is important to smooth the selection, configuration and composition of existing services to deal with the runtime changes or the evolution of End User requirements. In contrast to other traditional software systems, the dynamic behavior of service based systems requires up-to-date quality of service (QoS) information for its proper management in the different stages of the lifecycle. Organizations need to know the performance of Web services and business processes to maintain their sustainability for reuse of services. The three key benefits of service reuse are improving agility of solutions by quickly assembling new business processes from existing services to meet changing marketplace needs, reducing cost by not developing new services for enabling similar business functions across multiple business processes, but also spanning service deployment and management in runtime environments throughout the SOA lifecycle. However currently, there are many challenges related to the sustainability and governance of service behavior during its lifecycle. Among those challenges, one can mention level of performance, persistence of the requirements and adaptability of the service. Moreover, there are some limitations of monitoring tools. They lack of anticipation in problem detection, and they are passive and neither reactive nor predictive. This thesis focuses on providing assessment and recommendations for performance and governance of information systems for suggesting service reuse during its evolution. The aim is to maintain sustainability, robustness, adaptability, reusability and evolvability of information systems For this purpose, we evaluate the performance of service oriented architecture. There are several existing monitoring solutions designed to support a specific layer of SOA. Particularly, BAM is a business activity monitoring tool for monitoring the flow of data for business processes. However, BAM monitoring do not provide the performance evaluation for recommending services and processes to reuse. There are very few approaches that support monitoring of SOA layers together. Furthermore, the solutions are partially dynamic with limited decision support. Therefore, we propose performance based decision support for service oriented architecture. It consists of four layers as specification, data management, data mining and decision layers. The specification layer identifies the requirements from the End User and process through the proposed ontology. The data layer analyzes technical indicators that are compliant to the latest quality standard, ISO 25010. Quality characteristics are related to performance efficiency, reliability and reusability. The data mining layer generates specific decisions based on service instances by applying the machine learning algorithms. It uses the proposed ontological concepts and semantic inference rules of service, business process, server and integration layers. The data mining layer returns back to ontologies with these specific decisions where more refined rules have been generated from new ontological concepts. The decision layer processes these results and generates a global decision in terms of recommendations. It provides multi-viewpoints decision to reuse existing services or suggesting their composition. To motivate the proposition of this approach, we illustrate the implementation of the proposed algorithms for all the four layers by a business process use case and data set of public repository of shared services. The output of our system is recommendation for reuse of atomic service, composite service and resource allocation provisioning. We ensure the sustainability, adaptability...
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Efeito da adição de ácidos fosfóricos no comportamento reológico de ligantes asfálticos puros e modificados com copolímero SBS / Effect of phosphoric acid in the rheological behavior of pure and modified asphalt binders with SBS copolymer

Sobreiro, Fernanda Pilati 27 March 2014 (has links)
A adição de modificadores no ligante asfáltico visando melhorar o seu comportamento é uma prática comum atualmente. Existem vários tipos de modificadores, entre eles o mais utilizado nas rodovias federais brasileiras é o copolímero SBS. Além dos polímeros, o ácido polifosfórico (PPA) é outro tipo de modificador que produz boas características quando adicionado ao ligante asfáltico. Apesar do efeito positivo, sabe-se que este material é importado, o que dificulta sua aquisição e pode tornar o produto final muito caro. Tendo em vista a possibilidade de se trabalhar com um produto de mesma base, mas de origem nacional, o que o tornaria o modificador mais acessível, optou-se por verificar o comportamento da adição de ácido fosfórico (PA85) ao ligante asfáltico. Sendo assim, o propósito desta tese é analisar o efeito da adição de ácidos fosfóricos no comportamento reológico de ligantes asfálticos puros e modificados com o copolímero SBS. Para tanto, realizou-se ensaios empíricos e reológicos com o intuito de verificar o comportamento destes materiais. Na primeira parte da pesquisa, dois ligantes asfálticos de base, CAP50/70 de classificação PG64-XX, (Replan e Lubnor), foram modificados somente com a adição dos dois ácidos (PPA e PA85), enquanto na segunda parte esses ligantes asfálticos de base foram modificados com o copolímero SBS com ou sem a presença dos ácidos. Os ensaios avaliados foram penetração, ponto de amolecimento, viscosidade rotacional, ensaio de fluência e recuperação sob tensão múltipla (MSCR), LAS modificado, e estabilidade à estocagem. De maneira geral, a adição dos modificadores melhora o comportamento dos ligantes asfálticos, tendo em vista que melhoram a recuperação, ficam menos sensíveis à deformação permanente e são mais tolerantes à fadiga. Pode-se constatar que o tipo de ligante asfáltico de base influencia diretamente o comportamento dos materiais, independente dos modificadores adicionados. A adição dos modificadores foi mais expressiva no ligante asfáltico proveniente da Replan. Em relação aos ácidos, conclui-se que a adição do PA85 foi satisfatória, uma vez que apresentou comportamento semelhante ao do ácido PPA, porém com efeito um pouco menos expressivo. A adição dos ácidos melhorou a estabilidade à es tocagem dos ligantes asfálticos modificados, e pode-se constatar que a adição de um destes modificadores permite a redução do teor do copolímero SBS. Quanto à capacidade de suporte de tráfego, a adição de altos teores desses modificadores não é viável, devido ao fato de apresentarem suporte similar a ligantes asfálticos modificados com teores baixos e intermediários. / The addition of modifiers in asphalt binder to improve its behavior is a common practice nowadays. There are many types of modifiers, among them the most used in the Brazilian federal highways is the SBS copolymer. In addition to polymers, polyphosphoric acid (PPA) is another type of modifier that produces good characteristics when added to asphalt binder. Despite the positive effects, it is known that this material is imported, which makes its purchase as well as the final product very expensive. Considering the opportunity to work with a product with the same basic component, but of national origin, which would make it the most affordable modifier, the present study decided to verify the behavior of the addition of phosphoric acid (PA85) to the asphalt binder. Therefore, the purpose of this thesis is to analyze the effect of the addition of phosphoric acid to the rheological behavior of pure and modified asphalt binders with the SBS copolymer. For both, empirical and rheological tests were conducted in order to verify the behavior of these materials/substances. In the first part of the research, two asphalt binders base CAP50/70 asphalt binder graded PG64-XX (Replan and Lubnor) were modified only with the addition of the two acids (PPA and PA85), while in the second part of these asphalt binders base were modified with SBS copolymer with or without the presence of acids. The tests evaluated penetration, softening point, rotational viscosity, multiple stress creep and recovery (MSCR), LAS modified, and storage stability. In general, the addition of the modifiers enhances the behavior of the asphalt binders, for they improve recovery, are less susceptible to rutting and are more resistant to fatigue. It was found that the type of asphalt binder base directly influences the behavior of materials, regardless of added modifiers. The addition of modifiers was greater in the asphalt binder from the Replan. Compared to acids, it is concluded that the addition of PA85 was satisfactory, since the performance was similar to the PPA acid behavior, but with slightly less significant effect. The addition of acid improved the storage stability of the modified asphalt binders, and it was found that the addition of such modifiers allows reducing the content of the SBS copolymer. Regarding the ability to support traffic, the addition of high levels of these modifiers is not feasible because they show similar support for modified asphalt binders with low and intermediate levels.
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Efeito da adição de ácidos fosfóricos no comportamento reológico de ligantes asfálticos puros e modificados com copolímero SBS / Effect of phosphoric acid in the rheological behavior of pure and modified asphalt binders with SBS copolymer

Fernanda Pilati Sobreiro 27 March 2014 (has links)
A adição de modificadores no ligante asfáltico visando melhorar o seu comportamento é uma prática comum atualmente. Existem vários tipos de modificadores, entre eles o mais utilizado nas rodovias federais brasileiras é o copolímero SBS. Além dos polímeros, o ácido polifosfórico (PPA) é outro tipo de modificador que produz boas características quando adicionado ao ligante asfáltico. Apesar do efeito positivo, sabe-se que este material é importado, o que dificulta sua aquisição e pode tornar o produto final muito caro. Tendo em vista a possibilidade de se trabalhar com um produto de mesma base, mas de origem nacional, o que o tornaria o modificador mais acessível, optou-se por verificar o comportamento da adição de ácido fosfórico (PA85) ao ligante asfáltico. Sendo assim, o propósito desta tese é analisar o efeito da adição de ácidos fosfóricos no comportamento reológico de ligantes asfálticos puros e modificados com o copolímero SBS. Para tanto, realizou-se ensaios empíricos e reológicos com o intuito de verificar o comportamento destes materiais. Na primeira parte da pesquisa, dois ligantes asfálticos de base, CAP50/70 de classificação PG64-XX, (Replan e Lubnor), foram modificados somente com a adição dos dois ácidos (PPA e PA85), enquanto na segunda parte esses ligantes asfálticos de base foram modificados com o copolímero SBS com ou sem a presença dos ácidos. Os ensaios avaliados foram penetração, ponto de amolecimento, viscosidade rotacional, ensaio de fluência e recuperação sob tensão múltipla (MSCR), LAS modificado, e estabilidade à estocagem. De maneira geral, a adição dos modificadores melhora o comportamento dos ligantes asfálticos, tendo em vista que melhoram a recuperação, ficam menos sensíveis à deformação permanente e são mais tolerantes à fadiga. Pode-se constatar que o tipo de ligante asfáltico de base influencia diretamente o comportamento dos materiais, independente dos modificadores adicionados. A adição dos modificadores foi mais expressiva no ligante asfáltico proveniente da Replan. Em relação aos ácidos, conclui-se que a adição do PA85 foi satisfatória, uma vez que apresentou comportamento semelhante ao do ácido PPA, porém com efeito um pouco menos expressivo. A adição dos ácidos melhorou a estabilidade à es tocagem dos ligantes asfálticos modificados, e pode-se constatar que a adição de um destes modificadores permite a redução do teor do copolímero SBS. Quanto à capacidade de suporte de tráfego, a adição de altos teores desses modificadores não é viável, devido ao fato de apresentarem suporte similar a ligantes asfálticos modificados com teores baixos e intermediários. / The addition of modifiers in asphalt binder to improve its behavior is a common practice nowadays. There are many types of modifiers, among them the most used in the Brazilian federal highways is the SBS copolymer. In addition to polymers, polyphosphoric acid (PPA) is another type of modifier that produces good characteristics when added to asphalt binder. Despite the positive effects, it is known that this material is imported, which makes its purchase as well as the final product very expensive. Considering the opportunity to work with a product with the same basic component, but of national origin, which would make it the most affordable modifier, the present study decided to verify the behavior of the addition of phosphoric acid (PA85) to the asphalt binder. Therefore, the purpose of this thesis is to analyze the effect of the addition of phosphoric acid to the rheological behavior of pure and modified asphalt binders with the SBS copolymer. For both, empirical and rheological tests were conducted in order to verify the behavior of these materials/substances. In the first part of the research, two asphalt binders base CAP50/70 asphalt binder graded PG64-XX (Replan and Lubnor) were modified only with the addition of the two acids (PPA and PA85), while in the second part of these asphalt binders base were modified with SBS copolymer with or without the presence of acids. The tests evaluated penetration, softening point, rotational viscosity, multiple stress creep and recovery (MSCR), LAS modified, and storage stability. In general, the addition of the modifiers enhances the behavior of the asphalt binders, for they improve recovery, are less susceptible to rutting and are more resistant to fatigue. It was found that the type of asphalt binder base directly influences the behavior of materials, regardless of added modifiers. The addition of modifiers was greater in the asphalt binder from the Replan. Compared to acids, it is concluded that the addition of PA85 was satisfactory, since the performance was similar to the PPA acid behavior, but with slightly less significant effect. The addition of acid improved the storage stability of the modified asphalt binders, and it was found that the addition of such modifiers allows reducing the content of the SBS copolymer. Regarding the ability to support traffic, the addition of high levels of these modifiers is not feasible because they show similar support for modified asphalt binders with low and intermediate levels.
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Short pulse q-switched longitudinally diode pumped solid state minilasers: generation, characterization and application / Trumpų impulsų kokybės moduliacijos išilgai diodais kaupinami kietojo kūno minilazeriai: generavimas, charakterizavimas ir panaudojimas

Slavinskis, Nerijus 30 June 2011 (has links)
The dissertation is dedicated to the detailed numerical modelling of generation dynamics of actively and/or passively Q-switched diode laser longitudinally pumped solid-state lasers, characterization of spatial and temporal laser properties and for the demonstration of application possibility of created minilasers. A detailed theoretical model for the description of generation dynamics using travelling wave approach is presented. In this model more parameters of active laser medium, pump sources and resonator architecture are taken into account. In this thesis the results which show the principal difference between results obtained using the laser travelling wave model and point laser model are presented. Using point laser model the problems of generated pulse timing jitter in passively Q-switched lasers are described and its lowering possibilities using different pumping methods are suggested. In this thesis new, based by the second order moment, laser beam characterisation by knife-edge method is presented. Also laser pulse compression possibilities in tetrachloride CCL4 medium are described. It is showed that using seed signal it is possible to obtain shorter (< 60 ps) and more stable optical pulses. In this thesis application possibilities of created minilasers are presented: the experimental results of the Z-scan measurements obtained using pulses with different pulse shapes for fused silica are presented; also experiments, in which, created minilasers for paper cleaning... [to full text] / Disertacija skirta diodais kaupinamų kietojo kūno lazerių su aktyviąja ir pasyviąja kokybės moduliacija generacijos dinamikos detalesnei skaitmeninei analizei, lazerio impulsų laikinių ir erdvinių parametrų charakterizavimui ir sukurtų minilazerių panaudojimo galimybių demonstracijai. Generacijos dinamikos detalesniai skaitmeniniai analizei, darbe pristatomas sukurtas bėgančiųjų bangų modelis, kuriame atsižvelgiama ne tik į daugelį procesų vykstančių lazerio aktyviajame elemente, bet ir į rezonatoriaus konfigūraciją bei kaupinimo šaltino parametrus. Pateikiami skaitinio modeliavimo rezultatai demonstruojantys šio modelio privalumus lyginant su dažniausiai naudojamu taškiniu lazerio modeliu. Naudojant taškinį lazerio modelį yra nagrinėjama generuojamų impulsų laikinio tirtėjimo problema pasyvios kokybės moduliacijos lazeriuose ir pasiūlyti mažinimo būdai naudojant skirtingus kaupinimo būdus. Darbe taip pat pateiktas naujas, antraisiais momentais pagrįstas, pluošto charakterizavimo judančiu peiliu metodas. Nagrinėjamos lazerių impulsų spūdos galimybės tetrachlorido CCL4 skystyje ir pademonstruota, kad naudojant užkrato signalą galima gauti trumpesnius (< 60 ps) ir stabilesnius optinius impulsus. Darbe pademonstruotos sukurtų minilazerių pritaikymo galimybės: aprašomas netiesinio lūžio rodiklio kvarciniame stikle matavimas Z-skenavimo metodu ir gautų duomenų apdorojimo procedūra įskaitant naudojamų impulsų erdvinę ir laikinę formą; aprašomi eksperimentai, kuriuose sukurti... [toliau žr. visą tekstą]

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