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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.
31

Forest disappearance by firewood consumption in the Amazon estuary

Tsuchiya, Akio, Hiraoka, Mario 10 April 2018 (has links)
Deforestation of flooded (várzea) and non-flooded (terra firme) forests caused by firewood consumption at tile factories (olaria) was investigated in Abaetetuba Island at the Amazon estuary. Várzea is spatially limited, the area is only 3% of the whole Amazon, however, it is heavily influenced by human activities, especially by the cultivation of acaí palm (Euterpe oleracea Mart.). The trees are cut down for the olarias. The number of tree species are small, and they have less wood density than terra firme tree species because the várzea is flooded twice a day throughout the year. Terra firme forests, which are also secondary forests, receive less human impact, and have more tree species and more individual trees with a growth extension that exceeds the species in the várzea forests. The deforestation was examined by comparing forest biomass in a unit area to firewood consumption at olarias. The annual area of deforestation was estimated by using the combination of tree species in the firewood and human impact in the várzea forests. Then the estimation was extended to the whole island, assuming that the forests were rotatively cleared every 25 to 30 years. The results indicated that the area of deforestation was 6,870ha/25 years to 8,337ha/30 years, and that it was smaller than the island. However, logging is not only for fuel at olarias. If Belém's economic influence becomes stronger, and electric energy is not diffused throughout the island, the lumber consumption will accelerate and the increase might make the forest disappear faster than estimated.
32

Estudo e desenvolvimento de sistemas eletrônicos para o calorímetro hadrônico de telhas no cenário de alta luminosidade do LHC / Studies and development of electronic systems for the hadronic tile calorimeter in the high luminosity scenario of LHC

Schettino, Vinícius Barbosa 14 February 2014 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-02-11T11:12:28Z No. of bitstreams: 1 viniciusbarbosaschettino.pdf: 29158699 bytes, checksum: 73147768684934f5b11f6c844b4bbc4d (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-02-26T11:57:35Z (GMT) No. of bitstreams: 1 viniciusbarbosaschettino.pdf: 29158699 bytes, checksum: 73147768684934f5b11f6c844b4bbc4d (MD5) / Made available in DSpace on 2016-02-26T11:57:35Z (GMT). No. of bitstreams: 1 viniciusbarbosaschettino.pdf: 29158699 bytes, checksum: 73147768684934f5b11f6c844b4bbc4d (MD5) Previous issue date: 2014-02-14 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / O LHC é o mais energético acelerador de partículas já construído. Operado pelo CERN, essa fantástica máquina encontra-se no subterrâneo, na região da fronteira franco-suíça. Um de seus principais experimentos, o ATLAS, está atualmente passando por um período de parada técnica planejada, visando concomitantemente a consolidação da estrutura eletrônica do detector e a substituição de tecnologias, preparando o experimento para um novo estágio de operação do LHC, em que haverá um grande aumento na taxa de colisões entre prótons. Nesse contexto, essa dissertação abordará o estudo e o desenvolvimento de sistemas eletrônicos para o TileCal, um dos calorímetros do ATLAS. Principalmente, serão discutidos dois novos sistemas: O Sistema Móvel de Checagem da Integridade das Gavetas, conhecido como Mobi- DICK, e o projeto Tile-Muon. Relativamente ao primeiro, serão expostos detalhes da quarta versão de um sistema utilizado para realizar checagens quantitativas e qualitativas da eletrônica do TileCal. Esta nova versão, implementa ainda a estrutura que possibilita a realização de testes nas novas tecnologias que serão utilizadas no calorímetro. O ambicioso projeto Tile-Muon visa a utilização do TileCal para identificação de múons, com o objetivo de tornar mais eficiente a seleção de eventos do ATLAS. Essa proposta requer o desenvolvimento de uma nova estrutura eletrônica de suporte, que será apresentada nessa dissertação. Apresentaremos análises feitas com o MobiDICK sobre a eletrônica do TileCal, que mostrou boa performance, e também uma caracterização do sinal de múons, estudo fundamental para a validação e o desenvolvimento do projeto Tile-Muon. / The LHC is the most energetic particle accelerator ever built. Run by CERN, this fantastic machine lays underground, near the Franco-Swiss border. One of its main experiments, ATLAS, is currently going through a planned technical stop, targeting both a consolidation of the detector’s electronics and a technology replacement, preparing the experiment to a new stage in the LHC operation, where the protons collision rate will increase largely. In such context, this dissertation addresses the study and the development of electronic systems for TileCal, one of ATLAS calorimeters. Primarily, two new systems will be discussed: the Mobile Drawer Integrity Checking System, known as MobiDICK, and the Tile-Muon project. Regarding the former, we’ll bring details of the fourth version of a system used to check quantitatively and qualitatively the electronics of TileCal. This new version also provides the system with the ability to test the new technologies that will be used in the calorimeter. The ambitious Tile-Muon project aims at using TileCal for muon identification, with the goal of raising the efficiency of event selection in ATLAS. This proposal requires the development of a new electronic structure for support, which will also be presented in this dissertation. Analysis of TileCal’s electronics using MobiDICK will be shown, revealing good performance, along with a characterization of the muon signal, a fundamental study for validation and development of the Tile-Muon project.
33

Reciclagem de resíduos de indústria de placas cerâmicas: um estudo de caso / Recycling of residues of ceramic tile industry: a case study

Márcia Rodrigues de Morais Chaves 15 April 2002 (has links)
Reciclar é a palavra de ordem nos dias atuais. A escassez de matérias-primas, a economia com insumos, a preservação do meio ambiente e o ganho de confiabilidade com a melhora da imagem da empresa são alguns dos aspectos importantes da reutilização dos resíduos. Os lançamentos dos programas de qualidade de processos e produtos fizeram com que as indústrias buscassem meios de produzir mais e melhor, para suportar a competitividade no setor. Porém algumas indústrias brasileiras de revestimento cerâmico ainda produzem elevado índice de resíduos sólidos. Esses índices refletem a deficiência do processo produtivo, o prejuízo com o desperdício de matérias-primas e insumos, e causam o problema do descarte dos resíduos, uma vez que poucas indústrias se aventuram a reciclar, devido à falta de informação técnica. Nos últimos anos, com a crescente preocupação com as questões ambientais e, principalmente, com a implantação dos sistemas de gestão e certificação ambientais, vem sendo observada uma sensível melhora na política ambiental das indústrias de revestimento cerâmico. Mas é necessário, além das políticas, a orientação técnica às empresas, para a adequação de suas atividades em benefício ao meio ambiente. Frente a esses problemas, a presente pesquisa desenvolve um necessário estudo científico, caracterizando e classificando os resíduos, bem como propondo métodos de reutilização baseados em análises experimentais. De acordo com os resultados obtidos, é possível reciclar totalmente os resíduos das lamas do processo de esmaltação e dos resíduos queimados, sem alterar as condições industriais de processamento das placas, obtendo-se, em alguns casos, a melhoria das propriedades mecânicas das peças, recuperando os resíduos como matéria-prima, extinguindo o problema de disposição dos resíduos, e, conseqüentemente, os riscos ao meio ambiente / Currently recycling is a necessity. The scarcity of raw materials, the economy of resources and labor costs, the preservation of the environment and the gain in confidence with improvement of the company image are some of the important aspects of residue reutilization. The initiation of programs of process and product quality control has made industries searched for ways to produce more and better products in order to be competitive in the sector. However, some Brazilian ceramic tile industries still produce high indices of solid residues. These indices reflect the deficiencies of the production process, losses due to waste of raw materials and resources and labor costs, and cause the problem of the discarding of the residue, since few industries venture to recycle, due to lack technical information. In recent years, with the increasing concern with environmental questions and, mainly with the implantation of environmental management systems and certification, a sensible improvement in the environmental politics of the ceramic tile industries has been observed. However, it is necessary, in addition to these policies, the technical orientation of the companies, to adaptation of its activities in benefit of the environment. Considering these problems, the present research develops a necessary scientific study, characterizing and classifying the residue, as well as proposing methods of reutilization based on experimental analyses. According to the results obtained, it is possible to recycle the mud residues of the enameling and glazing processes, without modifying the industrial conditions of the tile processing. In some cases, obtaining an improvement of the mechanical properties of the pieces, recuperating the residue as raw material, and eliminating the residue disposal problem, and consequently, the risks to the environment
34

Vilka alternativ finns till deponering : En plockanalys av deponifraktion från återvinningscentral

Vollan Johansson, Cecilia January 2020 (has links)
Today, a large part of the recycling facilities inert waste goes to landfill.  Landfilling with waste leads to greenhouse gasemissions and the accumulation of pollutants that are liable to leak into the surrounding environment. Water and waste expertise in Norr AB (Vakin) is responsible for all waste management in the municipality of Umeå and Vindeln and aims to climb up the waste hierarchy by finding ways to recycle landfill waste. Today 100% of the landfill fraction is deposited. The purpose of the study is to investigate alternative treatment methods of waste in a landfill fraction, to reduce the amount of landfill waste. A sorting analysis was performed at Dåva landfill and waste facility in Umeå AB (Dåva DAC) to investigate the waste content in a landfill fraction. Interview questions were sent via e-mail to communal recycling centers to compare the handling and content of the required landfill fraction. The result show that landfill fraction contained hazardous waste, glass, porcelain, concrete, plasterboard/insulation, metal, combustible/plastic, brick, stone, tile/clinker and cardboard. To recycle construction and demolition waste, the fraction must be uniform and free of extraneous material The conclusion is that concrete, tile/clinker, brick and stone are sub-fractions that have the greatest potential for recycling. With a better waste sorting at the recycling facility, the amount of landfill fraction can be reduced.
35

Influence of Tile Drains on Sediment Connectivity between Shallow Agricultural Terrain and Snyder's Ditch, Orwell, Ohio: Baseline Assessment

Stull, Hannah January 2014 (has links)
No description available.
36

Tile flow from a stratified anisotropic soil with a falling water table

Hoffman, Glenn Jerrald January 1963 (has links)
No description available.
37

Rejuntamento de revestimentos cerâmicos: influência das juntas de assentamento na estabilidade de painéis. / Grouting of ceramic tiles: influence of joints in stress relief.

Junginger, Max 18 July 2003 (has links)
Este trabalho apresenta uma revisão bibliográfica a respeito dos rejuntes para revestimento cerâmico. A nomenclatura internacional é explorada e os tipos de rejunte e seus empregos são enumerados. Para embasar o leitor sobre o reves-timento cerâmico, os principais conceitos a ele relacionados são exibidos de forma sucinta. Uma vez que o rejunte é um componente importante do revestimento ce-râmico, suas funções dentro desse subsistema são abordadas em detalhes. O as-pecto de alívio de tensões é amplamente comentado, uma vez que essa é uma função essencial do rejunte, particularmente no caso de fachadas. Ao final, são abordados os aspectos de preparo e aplicação dos rejuntes, particularmente os produtos cimentícios. O rejuntamento de locais específicos, como encontros com selantes e interfaces com aparelhos sanitários são detalha-dos com vistas à diminuição da ocorrência de manifestações patológicas futuras. No trabalho experimental, painéis em forma de laje revestidos com placas cerâmicas são submetidos à flexão até a ocorrência de desplacamento, objeti-vando detectar qual a influência da largura da junta e do tipo de argamassa ade-siva na ruptura do corpo-de-prova. Os resultados indicam que a largura das juntas de assentamento assumem importância apenas quando a argamassa adesiva apresenta alta resistência de aderência. / This study presents a bibliographical revision regarding the ceramic tile grouts. Here, the international nomenclature is explored and the types of grouts as well as its employments are enumerated. To base the reader on the ceramic tile cladding, its main concepts are shown succinctly. Being the grout an important component of the ceramic tile cladding, its functions in this subsystem are broached in details. The aspect of stress relief is widely mentioned, for this is an essential function of grout, particularly in the case of facades. In the end, the aspects of the preparation and the application of grouts are broached, particularly the cementitious products. The grouting of specific places such as meetings of sealants and interfaces with sanitary devices is detailed viewing the decrease of the occurrence of future problems. In the experimental study, panels in flagstone form tiled with ceramic plates are submitted to flexion until the occurrence of rupture of these panels, aiming to detect the influence of the joint thickness and of the type of the adhesive mortar in the rupture of the sample. The results indicate that the nesting joint thickness only assumes importance when the adhesive mortar presents high resistance of adherence.
38

Kakelugnar : en studie av Emil Petterssons kakelugnsmatriser / Historic tile stoves : the tile matrices of Emil Pettersson

Jansson, Emelie January 2013 (has links)
In recent centuries the Swedish Tiled Stove has varied in its design with an aesthetic evolutionary history that has not only followed the architectural and artistic ideals but also the taste in stove design. The heat source has varied depending on the regional traditions and where it was located within the country, but the inside of the construction was of a similar five channel system. The purpose of this paper is to study and compare the design of tile matrices made by Emil Petterson with other Swedish stoves.  The following questions will be addressed: What characterized the production of a small scale tile stove workroom during the years 1900-50? Which main styles can be described as Emil Pettersson’s ideal while producing his matrices? And finally, is it possible to study the tile stove matrices as objects of historical and cultural significance, and what difficult methodological issues might occur in the doing of it?  To answer these questions I will present the results of the documentation of Pettersson’s tile matrices with detailed historical categorizations and schedules. The conclusion shows that Pettersson as a stove builder and -producer was characterized by eclectic ideals and a design shape based on more liberal interpretations of contemporary trends. The studying of tile stove matrices showed that, despite its difficulties regarding the inverted shapes, it is a barer of great historical and cultural value and that it plays a key part in the historical context of tile stove ovens.
39

Rejuntamento de revestimentos cerâmicos: influência das juntas de assentamento na estabilidade de painéis. / Grouting of ceramic tiles: influence of joints in stress relief.

Max Junginger 18 July 2003 (has links)
Este trabalho apresenta uma revisão bibliográfica a respeito dos rejuntes para revestimento cerâmico. A nomenclatura internacional é explorada e os tipos de rejunte e seus empregos são enumerados. Para embasar o leitor sobre o reves-timento cerâmico, os principais conceitos a ele relacionados são exibidos de forma sucinta. Uma vez que o rejunte é um componente importante do revestimento ce-râmico, suas funções dentro desse subsistema são abordadas em detalhes. O as-pecto de alívio de tensões é amplamente comentado, uma vez que essa é uma função essencial do rejunte, particularmente no caso de fachadas. Ao final, são abordados os aspectos de preparo e aplicação dos rejuntes, particularmente os produtos cimentícios. O rejuntamento de locais específicos, como encontros com selantes e interfaces com aparelhos sanitários são detalha-dos com vistas à diminuição da ocorrência de manifestações patológicas futuras. No trabalho experimental, painéis em forma de laje revestidos com placas cerâmicas são submetidos à flexão até a ocorrência de desplacamento, objeti-vando detectar qual a influência da largura da junta e do tipo de argamassa ade-siva na ruptura do corpo-de-prova. Os resultados indicam que a largura das juntas de assentamento assumem importância apenas quando a argamassa adesiva apresenta alta resistência de aderência. / This study presents a bibliographical revision regarding the ceramic tile grouts. Here, the international nomenclature is explored and the types of grouts as well as its employments are enumerated. To base the reader on the ceramic tile cladding, its main concepts are shown succinctly. Being the grout an important component of the ceramic tile cladding, its functions in this subsystem are broached in details. The aspect of stress relief is widely mentioned, for this is an essential function of grout, particularly in the case of facades. In the end, the aspects of the preparation and the application of grouts are broached, particularly the cementitious products. The grouting of specific places such as meetings of sealants and interfaces with sanitary devices is detailed viewing the decrease of the occurrence of future problems. In the experimental study, panels in flagstone form tiled with ceramic plates are submitted to flexion until the occurrence of rupture of these panels, aiming to detect the influence of the joint thickness and of the type of the adhesive mortar in the rupture of the sample. The results indicate that the nesting joint thickness only assumes importance when the adhesive mortar presents high resistance of adherence.
40

Разработка технологии получения глазурованного керамогранита : магистерская диссертация / Development of technology for the production of glazed porcelain tila

Ершова, А. А., Ershova, A. A. January 2018 (has links)
The work is devoted to the development of mass compositions for the production of engobe and glaze for the production of glazed ceramic granite: raw materials are selected; their properties are investigated; firing modes are determined. / Работа посвящена разработке составов масс для получения ангоба и глазури для производства глазурованного керамического гранита: подобраны сырьевые материалы; исследованы их свойства; определены режимы обжига.

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