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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.
231

Perméation des gaz dans les polymères semi-cristallins par modélisation moléculaire / Gas permeability in the semi-crystalline polymers using molecular modelling

Memari Namin, Peyman 16 February 2011 (has links)
La perméabilité aux gaz et aux liquides des matériaux polymères est une propriété qui est mise à profit dans de nombreux domaines industriels. Cette thèse est effectuée dans l'optique de mieux appréhender la problématique de l'étanchéité des conduites flexibles par les polymères. Ainsi, les perméabilités de H2S, CO2 et CH4 dans le polyéthylène (PE) ont fait l'objet d'une étude effectuée dans le contexte de cette thèse. La perméabilité est une propriété qui résulte de la solubilisation des gaz dans le polymère puis de la diffusion de ces produits à travers la matière. La solubilité, qui caractérise l’aptitude d’un gaz à pouvoir s’absorber dans le polymère, est une propriété d’équilibre, qui pourra être étudiée par les techniques de Monte Carlo. La diffusion, qui caractérise l’aptitude d’un gaz à se mouvoir plus ou moins rapidement dans le réseau polymère, sera quant à elle, étudiée par dynamique moléculaire. Au dessous de la température de fusion, le polyéthylène est à l'état semi-cristallin. Cet état est composé de régions contenant des chaînes orientées aléatoirement (régions amorphes) et des régions contenant des chaînes orientées sur un réseau (régions cristallines). La morphologie complexe des polymères semi-cristallins présente des hétérogénéités de dimensions nanométriques, ce qui est difficilement accessible par la simulation moléculaire. A fin d'étudier la solubilité et la diffusion de gaz dans le polyéthylène semi-cristallin, nous modéliserons uniquement la phase amorphe au cours de ce travail. Par contre, l’effet des régions cristallines sur la phase amorphe sera pris en compte dans la simulation par une contrainte ad-hoc. / The gas permeability through the polymers is a property that is exploited in many industrial fields. The objective of this thesis is to better understand the problem of sealing of flexible pipes with polymers. Thus, the permeability of H2S, CO2 and CH4 in polyethylene (PE) was studied during this work. Permeability is a property resulting from the dissolution of gases in the polymer and then diffusion of these products through the material. Solubility, which characterizes the ability of a gas to be absorbed in the polymer, is a property of equilibrium, which can be studied by Monte Carlo techniques. Diffusion coefficient, which characterizes the ability of a gas to move more or less rapidly into the polymer network, will in turn studied by molecular dynamics.Below the melting temperature, polyethylene is in semi-crystalline state. This state is composed of regions containing randomly oriented chains (amorphous regions) and regions containing chains oriented regularly on a network (crystalline regions). The complex morphology of semi-crystalline polymers has nanometric heterogeneities, which is not easily accessible by molecular simulation. In order to study the solubility and diffusion coefficient of gases in semi-crystalline polyethylene, we model only the amorphous phase in this work. However, the effect of crystalline regions on the amorphous phase will be taken into account in the simulation by an ad-hoc constraint.
232

O princípio da vedação ao retrocesso social e sua aplicação ao regime jurídico dos servidores públicos

Sparapani, Priscilia 09 May 2013 (has links)
Made available in DSpace on 2016-04-26T20:21:37Z (GMT). No. of bitstreams: 1 Priscilia Sparapani.pdf: 1195786 bytes, checksum: 46ea77a4cfbbf6d6d95d7879fa8d2d39 (MD5) Previous issue date: 2013-05-09 / This thesis objective is to present the study of the principle of sealing the social regression and its application to the legal framework of public officeholders effective, and understand the changes imposed on the server s rights and guarantees as a result of a series of constitutional amendments enacted that fundamentally altered their rights and guarantees. With this in mind, there will be a subject examination, a presentation will be built, based on the various ways that the state entity has taken over its evolutionary process. It is noteworthy that such exposure involves not only legal aspects, but social, political and economic with the same relevance; that bias is part of the larger context of historical models of rule of law and the construction of Administrative Law that accompanies evolution of the state to get to the current stage of the Brazilian neo-contemporary social and Administrative Law on land homelands. After passes to the examination of the social backlash as sealing principle of the rule of law: first in foreign law, analyzing the doctrinal and jurisprudential thought about it, then their presence the national laws, so implicit in the Federal Constitution 1988, including analysis of trial of Brazilian High Courts of Justice on the matter. Finally, we analyze the application of the rule of no social backlash to the legal regime of public officeholders effective. Alluded analysis is done, first, by exposing all of the changes in relation to ensuring the stability of the remuneration system and the pension system for civil servants. Then the critical examination of the subject is done by dividing the subject into five main points: the role of the Supreme Court to control the rights and guarantees of civil servants, the importance of immutable clauses in Democracy and Human Rights Protection and guarantees of public officeholders effective, the principle of sealing and protecting the social backlash that confers the rights and guarantees of civil servants, the legal occupant of the public servant position and effective social protection of vested rights, and also The sealing principle of the social backlash and legal equivalence. The academic study is justified by the importance of the issue, since the issue of sealing the social backlash is still new and quite controversial, especially on account of the divergence of doctrine as to the basis, content and scope of the principle, which reflects the small amount of judicial decisions involving the principle of sealing the social regression in the Superior Courts. As a research method was used in this study both the deductive method, as the inductive. Through the analysis, primarily of doctrinal works and in addition, jurisprudence, particularly the Supreme Court, were discussed the issues surrounding the subject. And before all the study, it is concluded that the changes in the legal regime of public servants not offend the principle of sealing the social backlash observe the equivalence legal and fair distribution of resources. And, in this step, the social backlash should not be conceived as a principle guaranteeing the highest level reached by the community rights of public servants occupying positions of effective provision / O objetivo desta tese consiste em apresentar o estudo do princípio da vedação ao retrocesso social e sua aplicação ao regime jurídico dos servidores públicos ocupantes de cargos efetivos. Busca-se compreender as mudanças instituídas nos direitos e garantias desses servidores, como decorrência de uma série de emendas constitucionais promulgadas que alteraram profundamente seus direitos e garantias. Com esse intuito, inicia-se o exame do tema, tecendo uma exposição sobre as diversas formas que o ente estatal assumiu ao longo do seu processo evolutivo. Destaca-se que referida exposição não envolve somente aspectos jurídicos, mas adentra, igualmente, em aspectos sociais, políticos e econômicos; nesse viés, parte-se do contexto maior dos modelos históricos de Estado de Direito e a construção do Direito Administrativo que acompanha a evolução do Estado até chegar ao atual estágio do Estado brasileiro neossocial e o Direito Administrativo contemporâneo em terras pátrias. Após, passa-se ao exame da vedação ao retrocesso social como princípio do Estado de Direito: primeiro no direito estrangeiro, analisando-se o pensamento doutrinário e jurisprudencial sobre o assunto; depois, sua presença no ordenamento jurídico pátrio, de modo implícito na Constituição Federal de 1988; incluindo análise dos julgados das Cortes Superiores de Justiça brasileiras acerca da matéria. Por fim, analisa-se a aplicação do primado do não retrocesso social ao regime jurídico dos servidores públicos ocupantes de cargos efetivos. Aludida análise é feita, primeiramente, por meio da exposição das mudanças todas em relação à garantia da estabilidade, do regime remuneratório e do regime previdenciário dos servidores públicos. Em seguida, o exame crítico do tema é feito por meio da divisão do assunto em cinco pontos principais: o papel do Supremo Tribunal Federal no controle dos direitos e garantias dos servidores públicos; a importância das cláusulas pétreas na democracia e a proteção aos direitos e garantias dos servidores públicos ocupantes de cargos efetivos; o princípio da vedação ao retrocesso social e a proteção que confere aos direitos e garantias dos servidores públicos; o regime jurídico do servidor público ocupante de cargo efetivo e a proteção do direito adquirido social; e, também, o princípio da vedação ao retrocesso social e a equivalência jurídica. O estudo acadêmico é justificado pela importância do assunto, uma vez que o tema da vedação ao retrocesso social é ainda novo e bastante polêmico, especialmente em virtude da própria divergência da doutrina quanto ao fundamento, conteúdo e alcance do princípio, o que reflete na pequena quantidade de decisões judiciais que envolvem o princípio da vedação ao retrocesso social nos Tribunais Superiores. Como método de pesquisa foram utilizados neste trabalho tanto o método dedutivo quanto o indutivo. Por intermédio da análise, fundamentalmente, de obras doutrinárias e, complementarmente, de jurisprudência, em especial do Supremo Tribunal Federal, foram abordadas as questões que envolvem o assunto. E, diante de todo o estudo, conclui-se que as alterações no regime jurídico do servidor público não ofendem o princípio da vedação ao retrocesso social se observarem a equivalência jurídica e a justa repartição de recursos. E, nesse passo, o não retrocesso social deve ser concebido como um princípio garantidor do nível mais elevado de direitos alcançado pela comunidade de servidores públicos ocupantes de cargos de provimento efetivo
233

Diacylglycerol, novel protein kinase C isozymes [eta] and [theta], and other diacylglycerol activated proteins promote neuroprotective plasmalemmal sealing in B104 neurons in vitro and rat sciatic nerve axons in vivo

Zuzek, Aleksej 25 February 2013 (has links)
To survive, neurons and other eukaryotic cells must rapidly repair (seal) plasmalemmal damage. Such repair occurs by an accumulation of intracellular vesicles at or near the plasmalemmal disruption. Diacylglycerol (DAG)-dependent and cAMP-dependent proteins are involved in many vesicle trafficking pathways. Although recent studies have implicated the signaling molecule cAMP in sealing, no study has investigated how DAG and DAG-dependent proteins affect sealing and, whether pharmacological inhibition of such proteins could promote immediate repair of damaged mammalian axons. To this end, I investigated the role of DAG, protein kinase C (PKC) and other DAG-activated proteins in plasmalemmal sealing in B104 neurons in vitro and rat sciatic nerves in vivo. Using dye exclusion to assess Ca2+-dependent vesicle-mediated sealing of transected neurites of individually identifiable rat hippocampal B104 cells, I now report that, compared to non-treated controls, sealing probabilities and rates are increased by DAG and cAMP analogs that activate PKC and Munc13-1, and protein kinase A (PKA). Sealing is decreased by inhibiting DAG-activated novel protein kinase C isozymes η (nPKCη) and θ (nPKCθ) and, Munc13-1, the PKC effector myristoylated alanine rich PKC substrate (MARCKS) or phospholipase C (PLC). DAG-increased sealing is prevented by inhibiting MARCKS or PKA. Sealing probability is further decreased by simultaneously inhibiting nPKCη, nPKCθ and PKA. Extracellular Ca2+, DAG or cAMP analogs do not affect this decrease in sealing. I also report that applying inhibitors of nPKC and PKA to rat sciatic axons crush-severed in vivo under physiological calcium, do not promote immediate repair by polyethylene glycol (PEG), as assessed by compound action potential conduction and dye diffusion through crush sites. These and other data suggest that DAG increases sealing through MARCKS and that nPKCη, nPKCθ and PKA are all required to seal plasmalemmal damage in B104 neurons, and likely all eukaryotic cells. / text
234

Kategese as middel tot heilsekerheid en heilstoe-eiening in konteks van die verbond en die koninkryk / Carel Nicolaas van der Merwe

Van der Merwe, Carel Nicolaas January 2004 (has links)
The observation is made that the spiritual well being of the church youth - i.e., the covenantal youth -is not healthy. The aim of this thesis is to study this observation. It seems that when children come to the point that they confess their faith they do not grasp the full implications of this undertaking as they do not bear the fruits of faith in their daily lives. There exists empiric evidence that the church youth are well equipped in the knowledge of faith, but when it comes to subjective acts of faith, there is a great lack. The assumption is made that the catechist is not always sufficiently equipped to apply the balance between knowledge of faith and subjective acts of faith in catechises. The focus point of the study is: Catechises as a means through which salvation is secured and appropriated within the context of the covenant and the Kingdom of God. The fundamental question at stake is: How does the believer share in the salvation that Christ has earned on the cross, and in which way can the catechises serves as a vehicle to achieve this goal. Essentially catechises is the official service of the church through which children of the covenant are assured of their salvation. They must also come to the point where they claim this redemption. The church obtains this objective by proclaiming the truths and instructing the doctrines of the Word of God to these children in such a way that each individual should come to confess his/her faith publicly and personally. Catechists must shepherd and guide these children not only to obtain certainty of faith (certitudo fidei) and to be obedient as believers, but also to be convinced of their salvation (certitudo salutis) and to make this redemption their own. The unity between God and man is not a polar one, but an apolar covenantal relation. Within this polar relation the covenant is like a solid foundation in which this oneness is rooted. The monopleuric (one-sided, unilateral) and dipleuric (two-sided, bilateral) character of the covenant proves that God treats man as a responsible associate in this treaty. God's sovereignty or objective salvation, on the one hand, and human responsibility or subjective faith, on the other hand, coexists without any strain or uneasiness whatsoever within this apolar covenantal connection between God and man. There is no contradiction between God's redemptive word and man's responsibility. It is therefore compulsory for man to believe; that man has faith is not something that rakes place without his decision. However, it is through the power of the gospel that faith is created in man - the gospel that Christ was crucified. The grace of God does not cause the believer to be a passive being; it has the effect that he is in active service of the Lord. The requirement to believe and to repent is not set aside; in fact, it remains a condition of the covenant. This means that, in the relation between God and His people, the promises and the demands of the covenant must be operative and active in the personal lives of the people of the covenant. The purpose of this exercise is that the believers will be able to experience the grace of the promises of the covenant as a reality. There is also a call at the address of these people to appropriate the salvation promised in the covenant. The children of the covenant must share in the promises of the pact on a personal basis. The reality of these promises, as well as the urgency of the demands - according to the gospel of God - must be proclaimed to the catechumens. There is a close relationship between certainty of faith and the objective truths of religion. This certainty is built on the truths that form the content of the Word of God. Certainty of salvation links up with the subjective acts of faith. A believer takes part on a personal level in the redemptive work of Christ. The fact that he is saved, through this redemption, forms the foundation of the Christian's life. / Thesis (Ph.D. (Catechetics))--North-West University, Potchefstroom Campus, 2005.
235

Perméation des gaz dans les polymères semi-cristallins par modélisation moléculaire / Gas permeability in the semi-crystalline polymers using molecular modelling

Memari Namin, Peyman 16 February 2011 (has links)
La perméabilité aux gaz et aux liquides des matériaux polymères est une propriété qui est mise à profit dans de nombreux domaines industriels. Cette thèse est effectuée dans l'optique de mieux appréhender la problématique de l'étanchéité des conduites flexibles par les polymères. Ainsi, les perméabilités de H2S, CO2 et CH4 dans le polyéthylène (PE) ont fait l'objet d'une étude effectuée dans le contexte de cette thèse. La perméabilité est une propriété qui résulte de la solubilisation des gaz dans le polymère puis de la diffusion de ces produits à travers la matière. La solubilité, qui caractérise l’aptitude d’un gaz à pouvoir s’absorber dans le polymère, est une propriété d’équilibre, qui pourra être étudiée par les techniques de Monte Carlo. La diffusion, qui caractérise l’aptitude d’un gaz à se mouvoir plus ou moins rapidement dans le réseau polymère, sera quant à elle, étudiée par dynamique moléculaire. Au dessous de la température de fusion, le polyéthylène est à l'état semi-cristallin. Cet état est composé de régions contenant des chaînes orientées aléatoirement (régions amorphes) et des régions contenant des chaînes orientées sur un réseau (régions cristallines). La morphologie complexe des polymères semi-cristallins présente des hétérogénéités de dimensions nanométriques, ce qui est difficilement accessible par la simulation moléculaire. A fin d'étudier la solubilité et la diffusion de gaz dans le polyéthylène semi-cristallin, nous modéliserons uniquement la phase amorphe au cours de ce travail. Par contre, l’effet des régions cristallines sur la phase amorphe sera pris en compte dans la simulation par une contrainte ad-hoc. / The gas permeability through the polymers is a property that is exploited in many industrial fields. The objective of this thesis is to better understand the problem of sealing of flexible pipes with polymers. Thus, the permeability of H2S, CO2 and CH4 in polyethylene (PE) was studied during this work. Permeability is a property resulting from the dissolution of gases in the polymer and then diffusion of these products through the material. Solubility, which characterizes the ability of a gas to be absorbed in the polymer, is a property of equilibrium, which can be studied by Monte Carlo techniques. Diffusion coefficient, which characterizes the ability of a gas to move more or less rapidly into the polymer network, will in turn studied by molecular dynamics.Below the melting temperature, polyethylene is in semi-crystalline state. This state is composed of regions containing randomly oriented chains (amorphous regions) and regions containing chains oriented regularly on a network (crystalline regions). The complex morphology of semi-crystalline polymers has nanometric heterogeneities, which is not easily accessible by molecular simulation. In order to study the solubility and diffusion coefficient of gases in semi-crystalline polyethylene, we model only the amorphous phase in this work. However, the effect of crystalline regions on the amorphous phase will be taken into account in the simulation by an ad-hoc constraint.
236

Kategese as middel tot heilsekerheid en heilstoe-eiening in konteks van die verbond en die koninkryk / Carel Nicolaas van der Merwe

Van der Merwe, Carel Nicolaas January 2004 (has links)
The observation is made that the spiritual well being of the church youth - i.e., the covenantal youth -is not healthy. The aim of this thesis is to study this observation. It seems that when children come to the point that they confess their faith they do not grasp the full implications of this undertaking as they do not bear the fruits of faith in their daily lives. There exists empiric evidence that the church youth are well equipped in the knowledge of faith, but when it comes to subjective acts of faith, there is a great lack. The assumption is made that the catechist is not always sufficiently equipped to apply the balance between knowledge of faith and subjective acts of faith in catechises. The focus point of the study is: Catechises as a means through which salvation is secured and appropriated within the context of the covenant and the Kingdom of God. The fundamental question at stake is: How does the believer share in the salvation that Christ has earned on the cross, and in which way can the catechises serves as a vehicle to achieve this goal. Essentially catechises is the official service of the church through which children of the covenant are assured of their salvation. They must also come to the point where they claim this redemption. The church obtains this objective by proclaiming the truths and instructing the doctrines of the Word of God to these children in such a way that each individual should come to confess his/her faith publicly and personally. Catechists must shepherd and guide these children not only to obtain certainty of faith (certitudo fidei) and to be obedient as believers, but also to be convinced of their salvation (certitudo salutis) and to make this redemption their own. The unity between God and man is not a polar one, but an apolar covenantal relation. Within this polar relation the covenant is like a solid foundation in which this oneness is rooted. The monopleuric (one-sided, unilateral) and dipleuric (two-sided, bilateral) character of the covenant proves that God treats man as a responsible associate in this treaty. God's sovereignty or objective salvation, on the one hand, and human responsibility or subjective faith, on the other hand, coexists without any strain or uneasiness whatsoever within this apolar covenantal connection between God and man. There is no contradiction between God's redemptive word and man's responsibility. It is therefore compulsory for man to believe; that man has faith is not something that rakes place without his decision. However, it is through the power of the gospel that faith is created in man - the gospel that Christ was crucified. The grace of God does not cause the believer to be a passive being; it has the effect that he is in active service of the Lord. The requirement to believe and to repent is not set aside; in fact, it remains a condition of the covenant. This means that, in the relation between God and His people, the promises and the demands of the covenant must be operative and active in the personal lives of the people of the covenant. The purpose of this exercise is that the believers will be able to experience the grace of the promises of the covenant as a reality. There is also a call at the address of these people to appropriate the salvation promised in the covenant. The children of the covenant must share in the promises of the pact on a personal basis. The reality of these promises, as well as the urgency of the demands - according to the gospel of God - must be proclaimed to the catechumens. There is a close relationship between certainty of faith and the objective truths of religion. This certainty is built on the truths that form the content of the Word of God. Certainty of salvation links up with the subjective acts of faith. A believer takes part on a personal level in the redemptive work of Christ. The fact that he is saved, through this redemption, forms the foundation of the Christian's life. / Thesis (Ph.D. (Catechetics))--North-West University, Potchefstroom Campus, 2005.
237

Flächennutzungsmonitoring - aktuelle Ergebnisse und Entwicklungen im IÖR-Monitor

Meinel, Gotthard, Krüger, Tobias, Schumacher, Ulrich, Hennersdorf, Jörg, Förster, Jochen, Köhler, Christiane, Walz, Ulrich, Stein, Christian 10 February 2015 (has links) (PDF)
Nach Darstellung der Anforderungen an ein zeitgemäßes Flächennutzungsmonitoring werden aktuelle Ergebnisse des Monitors der Siedlungs- und Freiraumentwicklung (IÖR-Monitor) vorgestellt. Diese beruhen insbesondere auf der Analyse topographischen Geobasisdaten von 2012 (mittlere Grundaktualität 2010). Die Siedlungs- und Verkehrsfläche steigt danach weiter ungemindert, sodass keine Entwarnung bzgl. des Erreichens der Flächensparziele gegeben werden kann. Da sich der IÖR-Monitor insbesondere auf die Auswertung des ATKIS Basis-DLM stützt, werden dessen jüngste Entwicklungen mit den Aspekten Aktualität und AAA-Migration vorgestellt. Erstmals werden die Ergebnisse des IÖR-Monitors durch Migrationseffekte geringfügig beeinflusst, die im Detail dargestellt werden. Anschließend werden neue Indikatoren der Kategorie Siedlung (Bodenversiegelungsgrad), Gebäude (Gebäudedichte und -überbauungsgrad) sowie Landschaftsqualität (Anteil naturbetonter Flächen und Hemerobieindex) erläutert. Inzwischen ist auch die kleinräumige Indikatordarstellung in Form von Rasterkarten bis 100-m-Rasterweite in einem integrierten Detailviewer mit GIS-Funktionalität möglich. Die technische Realisierung und die verfügbaren Indikatorkarten werden kurz vorgestellt. Der Beitrag schließt mit einem Ausblick auf die nächsten Arbeiten im IÖR-Monitor ab.
238

Avaliação do desempenho acústico de um sistema de construção modular: estudo de caso

Ribeiro, Rodrigo Scoczynski 30 March 2015 (has links)
O objetivo deste trabalho é avaliar o desempenho acústico de um sistema construtivo modular e industrializado por meio do método simplificado de campo indicado pelas normas ABNT NBR 15575-4:2013 e ISO 10052:2004, analisando as vedações verticais internas e externas quanto ao isolamento ao ruído aéreo e as comparando com análises já realizadas em outras edificações de trabalhos conhecidos. A indústria de construção civil, em todo o mundo, encontra-se em um momento dedicado à busca e implementação de estratégias de modernização do setor, a fim de se reduzir os custos e minimizar os desperdícios, investido em construções sustentáveis. Há uma necessidade de estudos baseados nos parâmetros da norma NBR 15575-4:2013 para a devida caracterização das tecnologias construtivas que surgem e ainda são consideradas novidade para o setor. A norma implica em uma série de exigências e recomendações, como por exemplo, o conforto acústico, que será abordado nesse trabalho. A metodologia utilizada foi baseada no método simplificado orientado pela ISO 10052:2004. Foram analisadas duas edificações de 40,0m2 cada. Uma delas é um sobrado, e a outra uma casa térrea. Foram feitas as medições de níveis de pressão sonora nos cômodos e nas fachadas, e as medições do tempo de reverberação dos cômodos. Depois de realizadas as medições foram feitas as análises pelo teste “t” de student. Em comparação com os padrões de outros países, percebeu-se que a norma ABNT NBR 15.575-4:2013 possui valores brandos, e que mesmo assim, as atuais técnicas construtivas brasileiras, em sua maior parte, não conseguem atingi-los. Através dos resultados encontrados, percebeu-se uma eficiência quanto ao isolamento ao ruído aéreo nas edificações modulares e industrializadas quando comparados às edificações de outras técnicas construtivas. Conclui-se, então, que o sobrado e a edificação térrea estão de acordo com os níveis de desempenho estabelecidos pelo norma ABNT NBR 15.575-4:2013. / The objective of this study is evaluate the modular and industrialized building system’s acoustic performance through the simplified field method indicated by ABNT NBR 15575-4:2013 and ISO 10052: 2004, analyzing the internal and external vertical seals for air noise insulation and comparing with previous analyzes in other approaches. The world construction industry is in a dedicated time to the pursuit and implementation of sector modernization strategies in order to reduce costs and minimize waste, invested in sustainable buildings. It’s is necessary studies based on the parameters of NBR 15575-4: 2013 for the proper characterization of building technologies that emerge and are still new to the sector. The standard implies a series of requirements and recommendations, such as the acoustic comfort, which will be addressed in this work. The methodology used was based on the simplified method guided by ISO 10052: 2004. Two buildings were analyzed, with 40,0m2 each. One of them is a two-story house, and the other is a ground floor building. Measurements of sound pressure levels were made in the rooms and on the frontages, and measurements of the reverberation time of rooms. After the measurements were made analyzes with test "t" student. Compared to the standards of other countries, it was realized that the ABNT NBR 15575-4: 2013 has soft values, and that even so, the current Brazilian construction techniques, for the most part, can not reach them. Through these results, it was noticed an efficiency about the isolation airnoise in modular and industrialized buildings compared to buildings of other construction techniques. It follows, then, that the floor and the ground floor building comply with the performance levels established by ABNT NBR 15575-4: 2013.
239

Avaliação do desempenho acústico de um sistema de construção modular: estudo de caso

Ribeiro, Rodrigo Scoczynski 30 March 2015 (has links)
O objetivo deste trabalho é avaliar o desempenho acústico de um sistema construtivo modular e industrializado por meio do método simplificado de campo indicado pelas normas ABNT NBR 15575-4:2013 e ISO 10052:2004, analisando as vedações verticais internas e externas quanto ao isolamento ao ruído aéreo e as comparando com análises já realizadas em outras edificações de trabalhos conhecidos. A indústria de construção civil, em todo o mundo, encontra-se em um momento dedicado à busca e implementação de estratégias de modernização do setor, a fim de se reduzir os custos e minimizar os desperdícios, investido em construções sustentáveis. Há uma necessidade de estudos baseados nos parâmetros da norma NBR 15575-4:2013 para a devida caracterização das tecnologias construtivas que surgem e ainda são consideradas novidade para o setor. A norma implica em uma série de exigências e recomendações, como por exemplo, o conforto acústico, que será abordado nesse trabalho. A metodologia utilizada foi baseada no método simplificado orientado pela ISO 10052:2004. Foram analisadas duas edificações de 40,0m2 cada. Uma delas é um sobrado, e a outra uma casa térrea. Foram feitas as medições de níveis de pressão sonora nos cômodos e nas fachadas, e as medições do tempo de reverberação dos cômodos. Depois de realizadas as medições foram feitas as análises pelo teste “t” de student. Em comparação com os padrões de outros países, percebeu-se que a norma ABNT NBR 15.575-4:2013 possui valores brandos, e que mesmo assim, as atuais técnicas construtivas brasileiras, em sua maior parte, não conseguem atingi-los. Através dos resultados encontrados, percebeu-se uma eficiência quanto ao isolamento ao ruído aéreo nas edificações modulares e industrializadas quando comparados às edificações de outras técnicas construtivas. Conclui-se, então, que o sobrado e a edificação térrea estão de acordo com os níveis de desempenho estabelecidos pelo norma ABNT NBR 15.575-4:2013. / The objective of this study is evaluate the modular and industrialized building system’s acoustic performance through the simplified field method indicated by ABNT NBR 15575-4:2013 and ISO 10052: 2004, analyzing the internal and external vertical seals for air noise insulation and comparing with previous analyzes in other approaches. The world construction industry is in a dedicated time to the pursuit and implementation of sector modernization strategies in order to reduce costs and minimize waste, invested in sustainable buildings. It’s is necessary studies based on the parameters of NBR 15575-4: 2013 for the proper characterization of building technologies that emerge and are still new to the sector. The standard implies a series of requirements and recommendations, such as the acoustic comfort, which will be addressed in this work. The methodology used was based on the simplified method guided by ISO 10052: 2004. Two buildings were analyzed, with 40,0m2 each. One of them is a two-story house, and the other is a ground floor building. Measurements of sound pressure levels were made in the rooms and on the frontages, and measurements of the reverberation time of rooms. After the measurements were made analyzes with test "t" student. Compared to the standards of other countries, it was realized that the ABNT NBR 15575-4: 2013 has soft values, and that even so, the current Brazilian construction techniques, for the most part, can not reach them. Through these results, it was noticed an efficiency about the isolation airnoise in modular and industrialized buildings compared to buildings of other construction techniques. It follows, then, that the floor and the ground floor building comply with the performance levels established by ABNT NBR 15575-4: 2013.
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Influência do selamento dentinário imediato na resistência de união de cimentos resinosos autoadesivos e convencionais / Influence of immediate dentin sealing on microtensile bond strength of composite resin cements

Vinicius Carvalho Brigagão 18 December 2013 (has links)
Objetivo: Avaliar a influência de diferentes tratamentos de superfície dentinária na resistência de união de cimentos resinosos convencionais e autoadesivos, bem como analisar a superfície de fratura. Metodologia: Foram elaborados quatro artigos científicos. No Capítulo 1 apresentou-se uma revisão de literatura acerca do selamento dentinário imediato, através de uma análise crítica sobre os materiais e métodos de aplicação clínica, baseado em estudos clínicos e in vitro. O Capítulo 2 descreve uma revisão da literatura sobre os cimentos resinosos autoadesivos, seu desempenho clínico e laboratorial na capacidade de união à dentina e diferentes substratos restauradores. Nos capítulos 3 e 4 estão descritos os trabalho in vitro, nos quais foram utilizados a metodologia de microtração e análise fractográfica para avaliação dos resultados de resistência de união. No capítulo 3 foi delineado um experimento com o objetivo de avaliar a resistência de união de um cimento resinoso autoadesivo (Rely X U200) utilizado para fixação de restaurações em dentina submetida a diferentes tratamentos de superfície: Grupo Controle nenhum tratamento; Grupo TC influência do cimento provisório antes da cimentação definitiva; Grupo PA condicionamento com ácido poliacrílico a 10%; Grupo DDS selamento dentinário tardio com adesivo universal (Single Bond Universal) aplicado antes da cimentação da restauração definitiva; Grupo IDS o mesmo adesivo aplicado imediatamente após a exposição dentinária. No capítulo 4 foi delineado outro estudo que avaliou diferentes formas (SE autocondicionante ou ER précondicionante) e momentos (IDS ou DDS) de aplicação do adesivo universal previamente à cimentação de restaurações utilizando cimento resinoso convencional (Rely X ARC). As formas de aplicação foram: pré-condicionamento e autocondicionamento, e os tempos de aplicação foram: selamento dentinário imediato (IDS) ou tardio (DDS). Os resultados de ambos os estudos laboratoriais foram submetidos à análise estatística (ANOVA e Tukey) com nível de significância de 5%. Conclusões: Foi possível concluir que os tratamentos da superfície dentinária promovem aumento dos valores de união de um cimento resinoso autoadesivo e que o selamento dentinário imediato aumenta de maneira significativa a resistência de união à dentina de um cimento resinoso convencional. / Objective: To evaluate the influence of different dentin surface treatments on the microtensile bond strength of adhesive and self adhesive resin cements, and fracture analysis. Metodology: Four scientific articles were made. Chapter 1 presented a literature review about immediate dentin sealing (IDS). Techniques and materials were assessed based on clinical studies and in vitro data. Chapter 2 describes a literature review about self adhesive resin cements, its clinical and laboratorial performance on the ability to bond to dentin surfaces and different restorative materials. Chapters 3 and 4 describe in vitro studies by microtensile bond strength (μ-TBS) and fracture analysis. Chapter 3 evaluated the μ-TBS of a self adhesive resin cement on the fixation of composite restorations under different dentin conditions: Control Group without treatment; Group TC influence of temporary cement before definitive luting; Group PA surface conditioning with 10% polyacrylic acid; DDS Group delayed dentin sealing (DDS) with universal adhesive system (Single Bond Universal) applied before cementation of composite restoration; IDS Group same adhesive system applied immediately after dentin exposure. Chapter 4 evaluated different techniques to apply a universal adhesive system before adhesive luting with Rely X ARC. The adhesive was applied in etch-and-rinse and self-etch mode, in different times: IDS and DDS. Results were submitted to ANOVA and Tukey complementary test at a significance of 5%. Conclusions: It was possible to conclude, among the limitations of an in vitro study, that dentin surface treatments are able to promote higher bond strength values when using a self adhesive resin cement (Rely X U200) and that IDS increases significantly the bond strength of Rely X ARC.

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