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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.
211

Tess evaluateur topologique predictif pour la generation automatique des plans de masse de circuits VLSI

Reis, Ricardo Augusto da Luz January 1983 (has links)
La prédiction de l'organisation topologique du plan de masse d'un circuit VLSI complexe est très importante pour sa conception. Cette thèse présente une étude sur les proprietés statistiques des dessins des masques des principaux blocs constituant un circuit intégré. Un outil prototype d'évaluation topologique est également présenté. Cet outil donne une évaluation de la forme et de la taille de ces blocs, à partir de leurs spécifications fonetionelles. Il est composé par un ensemble de sousprogrammes d'évaluation spécialisés pour les différents types de blocs fonetionnels qui peuvent constituer un circuit VLSI. / The prediction of the floor plan topological organization in the design process of a complex VLSI circuit is very important. This thesis presents a study about statistical properties of the main blocks that compose an integrated circuit. A prototype tool for topological evaluation is also presented. This tool provides an evaluation of the shape and size of these blocks from their functional specifications. It is composed of a set of evaluation rotines specialized for the different functional blocks which may constitute a VLSI circuit.
212

Tess evaluateur topologique predictif pour la generation automatique des plans de masse de circuits VLSI

Reis, Ricardo Augusto da Luz January 1983 (has links)
La prédiction de l'organisation topologique du plan de masse d'un circuit VLSI complexe est très importante pour sa conception. Cette thèse présente une étude sur les proprietés statistiques des dessins des masques des principaux blocs constituant un circuit intégré. Un outil prototype d'évaluation topologique est également présenté. Cet outil donne une évaluation de la forme et de la taille de ces blocs, à partir de leurs spécifications fonetionelles. Il est composé par un ensemble de sousprogrammes d'évaluation spécialisés pour les différents types de blocs fonetionnels qui peuvent constituer un circuit VLSI. / The prediction of the floor plan topological organization in the design process of a complex VLSI circuit is very important. This thesis presents a study about statistical properties of the main blocks that compose an integrated circuit. A prototype tool for topological evaluation is also presented. This tool provides an evaluation of the shape and size of these blocks from their functional specifications. It is composed of a set of evaluation rotines specialized for the different functional blocks which may constitute a VLSI circuit.
213

Nanofils de SiC : de la croissance aux dispositifs associés / SiC Nanowires : from growth to related devices

Choi, Jihoon 21 March 2013 (has links)
Les nanostructures de semi-conducteurs de faibles dimensions (comme les nanofils(NFs)) sont devenues l'objet de recherches intensives pour explorer de nouveaux phénomènes émergents à l'échelle nanométrique et sonder leur possibilités d’ utilisation dans l'électronique du futur. Parmi les différents nanofils semi-conducteurs, SiC a des propriétés très particulières, comme une large bande interdite, une excellente conductivité thermique, un haut champ électrique de claquage, une stabilité chimique et physique, une haute mobilité des électrons et une haute biocompatibilité.Nous proposons dans cette étude ; d'examiner une nouvelle approche pour fabriquer des nanostructures de SiC par l'approche « top-down ». Cela permet l'élaboration de nanostructures cristallines de SiC de haute qualité monocristalline avec un niveau de dopage contrôlé. Le comportement de nanostructures de SiC gravées a également été étudié en fonction de polytypes et des orientations cristallographiques.Nous avons également étudié les trois principaux sujets de SiC nano-devices pour atteindre une excellente performance. Pour répondre à ces questions, deux types de SiC nanoFET (SiC NFFET et SiC NPFET) ont été fabriqués et caractérisés par l'utilisation de nanofils de SiC et de nanopiliers de SiC préparés respectivement par les méthodes « bottom-up » et « top-down ». / Low dimensional semiconductor nanostructures, such as nanowires (NWs), have become the focus of intensive research for exploring new emergent phenomena at the nanoscale and probing their possible use in future electronics. Among these semiconductor NWs, Silicon Carbide (SiC) has very unique properties, such as wide bandgap, excellent thermal conductivity, chemical and physical stability, high electron mobility and biocompatibility. These factors makes SiC a long standing candidate material to replace silicon in specific electronic device applications operating in extreme conditions or/and harsh environments. SiC nanostructures have been studied extensively and intensively over the last decade not only for their fabrication and characterization, but also for their diverse applications. I have outlined the growth of SiC nanostructures based on different growth methods, a noteworthy feature of their characteristic properties and potential applications in the chapter one. As-grown SiC NWs fabricated by bottom-up method present a high density of structural defects, such as stacking faults. This kind of defect is one of the factors which lead to poor electrical performance (such as weak gate effect and low mobility) of the related devices. Therefore, it is required to develop a high quality of SiC nanostructures with low density of the structural defects using an alternative method, such as top-down process. Main objectives of this thesis are divided into three main parts. The first part of the thesis (Chapter two), we present the simulation results of the electrical transport and thermoelectric properties of SiC NWs. I have investigated the thermoelectric enhancement by studying the complex interplay of the size of NWs, temperature and surface roughness. Our simulation results show that the ZT of C terminated SiC NW (2.05×2.05 nm2) reaches a maximum value of 1.04 at 600K. The second part of the thesis (Chapter there) is devoted to the fabrication of high quality SiC nanostructures with controlled doping level. I have developed a top-down fabrication technique for high quality nanometer scale SiC nanopillars (NPs) using inductively coupled plasma etching. The etching behavior of SiC NPs has also been studied depending on polytypes and crystallographic orientations. Under the optimal etching conditions using a large circular mask pattern with 370 nm diameter, the obtained 4H-SiC nanopillars exhibit high anisotropy features (6.4) with a large etch depth (>7μm). A hexagonal, rhombus and triangle based pillar structures have been obtained using α-SiC (0001), 3C-SiC (001) and 3C-SiC (111) substrates, respectively. The last part of the thesis (Chapter four) is dedicated to the design and the electrical characterization of SiC nanodevices. To investigate the electrical properties of SiC nanostructures, two different kinds of SiC nanoFETs (SiC NWFET and SiC NPFET) have been fabricated by using SiC NWs and SiC NPs prepared via bottom-up method and top-down methods, respectively. In case of SiC NWFET, low resistivity ohmic contacts (378 kΩ) have been obtained after the annealing at 650 °C. Ni silicide intrusion into the SiC NW channel has been observed the annealing at 700 °C. This temperature is compared to one of other group IV materials. In case of SiC NPFET, two different types of NPFET (3C-SiC (001) and 4H-SiC (0001)) have been fabricated using our SiC nanopillars, obtained by top-down approach. The estimated values of the field-effect carrier mobility are 232.7 cm2⋅V-1s-1 for 3C-SiC (001) NPFET (#2) and 53.6 cm2⋅V-1s-1 for 4H-SiC (0001) NPFET, which is higher than the best values reported in the literature (15.9 cm2⋅V-1s-1).
214

A indu??o de capacidade estatal pela Uni?o junto aos governos estaduais do Brasil: o perfil do marco normativo federal de seguran?a p?blica

Silva, Marcos Ara?jo Mortoni 28 July 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-02-13T19:08:09Z No. of bitstreams: 1 MarcosAraujoMortoniSilva_DISSERT.pdf: 2156933 bytes, checksum: 94001b7817a83f4df5e33ea7125628b0 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-02-14T00:01:21Z (GMT) No. of bitstreams: 1 MarcosAraujoMortoniSilva_DISSERT.pdf: 2156933 bytes, checksum: 94001b7817a83f4df5e33ea7125628b0 (MD5) / Made available in DSpace on 2017-02-14T00:01:21Z (GMT). No. of bitstreams: 1 MarcosAraujoMortoniSilva_DISSERT.pdf: 2156933 bytes, checksum: 94001b7817a83f4df5e33ea7125628b0 (MD5) Previous issue date: 2016-07-28 / O trabalho investigou o perfil do marco normativo federal de seguran?a p?blica para a indu??o de capacidades estatais dos governos estaduais. A revis?o de literatura mostrou as conex?es entre as perspectivas de implementa??o de pol?ticas p?blicas, top-down ou bottom-up, a governan?a de pol?ticas e as capacidades estatais; revelando que a distin??o na perspectiva de implementa??o adotada pode levar a expectativas diferentes quanto ? variedade e ? extens?o das capacidades estatais de que devem dispor os governos, a depender da posi??o relativa que cada um destes ocupa no arranjo intergovernamental de pol?ticas p?blicas. Tamb?m foi verificado que a natureza pol?tica dos entes subnacionais, e a proximidade destes em rela??o aos cidad?os, quando comparados ? Uni?o, favorecem a compreens?o, a priori, pela atua??o dos governos locais em todas as etapas do processo de pol?ticas, o que, em uma abordagem intergovernamental de pol?ticas p?blicas, se aproximaria da perspectiva bottom-up. Sob esse prisma, uma capacidade verificada como necess?ria para o of?cio foi a capacidade relacional, compreendida como a interlocu??o cont?nua e satisfat?ria dos governos junto ? sociedade para o tratamento dos problemas que s?o considerados de natureza p?blica por essa mesma sociedade. As reflex?es sugeriram que a capacidade relacional poderia ser induzida a partir do fomento dos atributos de governan?a da pol?tica p?blica da jurisdi??o em que atuam os governos estaduais, tendo por precedente o mapeamento das condi??es socioecon?micas e demogr?fico-territoriais e da pr?pria governan?a da pol?tica de seguran?a p?blica da jurisdi??o. Um modelo de an?lise foi elaborado a partir dessas considera??es e adotado na realiza??o do trabalho. Os resultados revelaram que o marco normativo federal de seguran?a declina pouca aten??o ao conhecimento das realidades socioecon?micas e demogr?fico-territoriais das jurisdi??es dos governos estaduais e n?o apresenta refer?ncias voltadas ? identifica??o do perfil de governan?a da pol?tica estadual de seguran?a. Quanto ? indu??o em si, constatou-se que o marco normativo federal analisado alinha-se, majoritariamente, a perspectiva top-down de implementa??o, sinalizando para o desenvolvimento desta capacidade sob uma expectativa de atua??o dos governos estaduais enquanto implementadores das estrat?gias concebidas pela Uni?o. N?o obstante, foi verificada a presen?a subjacente e minorit?ria de refer?ncias ? indu??o de capacidades relacionais de governos estaduais sob a perspectiva bottom-up em todo o ciclo da pol?tica de seguran?a, ainda que em elementos normativos que disp?em de estrutura legal fr?gil ou em projeto de lei, em aprecia??o no Congresso Nacional. / The work researched the profile of federal regulatory and legal framework of public security for the induction of state capacities of state governments. The literature review revealed the link among implementation approaches (top-down or bottom-up), policy's governance, and state capacities, showing that differences on the perspective of implementation adopted may lead to distinct expectations regarding variety and length of state capacities that governments must have, according to the relative position that each one of the governments have at the intergovernmental arrangements of public policies. In this sense, it was verified that political nature of subnational governments, and the proximity of these regarding to citizens, if compared to the Uni?o, promote understanding, a priori, by the acting of local governments in all of the stages of policy process, that in an intergovernmental approach of public policy, would come close to bottom-up perspective. From this angle, a capacity verified as required was the relational capacity, understood as the satisfactory and regular dialogue of governments with society to address problems that are considered of public nature by that society. The analyzes suggested that relational capacity could be inducted from fostering of the governance?s attributes of the public policy in the jurisdiction that state governments operate, with previous mapping of socioeconomic and demographic-territorial conditions and the very governance of security public policy at the jurisdiction. An analysis model was conceived from these considerations and adopted in this research. Findings have shown that federal regulatory and legal framework of public security pays little attention to the socio-economic and demographic-territorial conditions of the areas in that state governments act and has no references aimed to identifying the governance profile of the security policy. Regarding induction itself, it was found that federal regulatory and legal framework apparently has greater adherence about topdown perspective of implementation, pointing out to the development of this capacity on an expectation of the actions of state governments as implementers of the strategies conceived by Uni?o. On the other hand, it was found the underlying and minority presence of references to the relational capacity-building of state governments under the bottom-up perspective on all security policy cycle, although positioned on initiatives that have fragile legal framework or project law still under consideration in Congress.
215

Reguladores da variação temporal e espacial da comunidade bacteriana em lagoa rasa subtropical

Kist, Danieli Ledur January 2012 (has links)
O bacterioplâncton é um dos grupos de organismos responsáveis pela remineralização de nutrientes em ecossistemas aquáticos, bem como produtor de biomassa através da alça microbiana. Compreender a dinâmica dessa comunidade em função da variação térmica, disponibilidade de recursos e pressão de predação pode fornecer elementos que auxiliem no gerenciamento dos recursos hídricos, através da aplicação direta desse conhecimento ou como subsídios na interpretação do resultado de simulações através de modelos ecológicos. Este trabalho teve como objetivo verificar a existência de heterogeneidade espacial e temporal na estrutura da comunidade bacteriana, densidade, biomassa e riqueza de morfotipos, na Lagoa Mangueira, bem como identificar as variáveis limnológicas que direcionam esses padrões. Foi evidenciada presença de heterogeneidade temporal, sazonal, e espacial do bacterioplâncton associada a dinâmica das variáveis limnológicas. A temperatura e a disponibilidade de nutrientes foram as principais variáveis que regularam as comunidades planctônicas, biomassa algal, bacterioplâncton e zooplâncton. Observou-se controle lateral, competição por nutrientes, entre as comunidades produtoras. O controle descendente, predação, mostrou ter importante efeito sobre o bacterioplâncton, mais especificamente sobre o morfotipo coccus, durante o verão e o inverno, sendo essa comunidade controlada de forma ascendente durante o outono e a primavera, principalmente por nitrogênio. Durante o inverno, a comunidade bacteriana apresentou significativa redução de densidade e biomassa, sendo que essa resposta pode estar relacionada às baixas temperaturas da água. A forma coccus foi o principal morfotipo produtor de biomassa e de maior densidade na lagoa. Importante heterogeneidade espacial foi observada na Lagoa Mangueira para as variáveis abióticas, visto que as regiões norte e sul apresentaram a maior diferenciação espacial, influenciada pela dimensão da lagoa. Fósforo total e carbono orgânico total regularam a comunidade bacteriana no norte da lagoa, especialmente os morfotipos coccus, curved e outros. Entre as zonas da lagoa, a margem oeste e leste foram as mais distintas em função da disponibilidade de nutrientes, destacando-se o carbono inorgânico total. A densidade bacteriana foi maior durante o verão, outono e inverno na região pelágica e durante a primavera na margem oeste da lagoa. A comunidade fitoplanctônica apresentou uma distribuição espacial caracterizada por maiores densidades nas regiões norte e centro da lagoa e na zona pelágica. O fósforo foi a principal variável limitante para as comunidades produtoras, fitoplâncton e bacterioplâncton, sendo o controle ascendente o principal regulador dessas comunidades, visto que o controle descendente não foi observado. Quanto à dinâmica dos organismos planctônicos e das variáveis limnológicas associados ao perfil de profundidade, a Lagoa Mangueira não apresentou estratificação das variáveis e consequentemente das comunidades planctônicas, resultado relacionado a uma possível característica de mistura completa da massa d’água, mesmo com ventos de baixa intensidade. As comunidades planctônicas apresentaram maior densidade durante o inverno, direcionadas pela maior disponibilidade de nitrogênio e fósforo. / Bacterioplankton is one of the groups of organisms responsible for the remineralization of nutrients in aquatic ecosystems, as well as a producer of biomass through the microbial loop. Understanding the dynamics of this community due to the thermal variation, resource availability and predation pressure may provide data to assist in the management of water resources through the application of that knowledge or direct subsidies in the interpretation of the results of simulations using ecological models. This work aimed to verify the existence of spatial and temporal heterogeneity in bacterial community structure, density, biomass and richness of morphotypes in Mangueira Lake, as well as identify the limnological variables that drive these patterns. We evidenced the presence of temporal heterogeneity, seasonal and spatial dynamics of bacterioplankton associated with limnological characteristics. The temperature and nutrient availability were the main variables that regulated the planktonic communities, algal biomass, bacterioplankton and zooplankton. There was lateral control, competition for nutrients, between the producing communities. The top down control, predation, was shown to have important effects on the bacterioplankton, more specifically on the coccus morphotype during the summer and winter, and this controlled community in bottom up controled during the fall and spring, mainly nitrogen. During the winter, the community had a significant reduction in bacterial density and biomass, and this response may be related to low water temperatures. Morphotype coccus was the main producing biomass and higher density in the lake. Important spatial heterogeneity was observed at Mangueira Lake for the abiotic variables, whereas the northern and southern regions had the highest spatial differentiation, influenced by the size of the lake. Total phosphorus and total organic carbon regulated bacterial community in the north of the lagoon, especially coccus morphotypes, curved and ‘others’. Among the areas of the lake, the west border and east were the most different depending on the availability of nutrients, especially if the total inorganic carbon. The bacterial density was higher during the summer, autumn and winter in the pelagic region and during the spring on the west border of the lake. The phytoplankton community showed a spatial distribution characterized by higher densities in the north and center of the lake and the pelagic zone. Phosphorus was the main variable limiting communities producing, phytoplankton and bacterioplankton, and bottom up control of these communities, since the top down control was not observed. Considering the dynamics of planktonic organisms and limnological variables associated with the depth profile, the Mangueira Lake did not show stratification of variables and consequently the planktonic communities, the result can be related to a characteristic of complete mixing of water mass, even with low wind intensity. The planktonic communities showed higher densities during the winter, driven by increased availability of nitrogen and phosphorus.
216

Reguladores da variação temporal e espacial da comunidade bacteriana em lagoa rasa subtropical

Kist, Danieli Ledur January 2012 (has links)
O bacterioplâncton é um dos grupos de organismos responsáveis pela remineralização de nutrientes em ecossistemas aquáticos, bem como produtor de biomassa através da alça microbiana. Compreender a dinâmica dessa comunidade em função da variação térmica, disponibilidade de recursos e pressão de predação pode fornecer elementos que auxiliem no gerenciamento dos recursos hídricos, através da aplicação direta desse conhecimento ou como subsídios na interpretação do resultado de simulações através de modelos ecológicos. Este trabalho teve como objetivo verificar a existência de heterogeneidade espacial e temporal na estrutura da comunidade bacteriana, densidade, biomassa e riqueza de morfotipos, na Lagoa Mangueira, bem como identificar as variáveis limnológicas que direcionam esses padrões. Foi evidenciada presença de heterogeneidade temporal, sazonal, e espacial do bacterioplâncton associada a dinâmica das variáveis limnológicas. A temperatura e a disponibilidade de nutrientes foram as principais variáveis que regularam as comunidades planctônicas, biomassa algal, bacterioplâncton e zooplâncton. Observou-se controle lateral, competição por nutrientes, entre as comunidades produtoras. O controle descendente, predação, mostrou ter importante efeito sobre o bacterioplâncton, mais especificamente sobre o morfotipo coccus, durante o verão e o inverno, sendo essa comunidade controlada de forma ascendente durante o outono e a primavera, principalmente por nitrogênio. Durante o inverno, a comunidade bacteriana apresentou significativa redução de densidade e biomassa, sendo que essa resposta pode estar relacionada às baixas temperaturas da água. A forma coccus foi o principal morfotipo produtor de biomassa e de maior densidade na lagoa. Importante heterogeneidade espacial foi observada na Lagoa Mangueira para as variáveis abióticas, visto que as regiões norte e sul apresentaram a maior diferenciação espacial, influenciada pela dimensão da lagoa. Fósforo total e carbono orgânico total regularam a comunidade bacteriana no norte da lagoa, especialmente os morfotipos coccus, curved e outros. Entre as zonas da lagoa, a margem oeste e leste foram as mais distintas em função da disponibilidade de nutrientes, destacando-se o carbono inorgânico total. A densidade bacteriana foi maior durante o verão, outono e inverno na região pelágica e durante a primavera na margem oeste da lagoa. A comunidade fitoplanctônica apresentou uma distribuição espacial caracterizada por maiores densidades nas regiões norte e centro da lagoa e na zona pelágica. O fósforo foi a principal variável limitante para as comunidades produtoras, fitoplâncton e bacterioplâncton, sendo o controle ascendente o principal regulador dessas comunidades, visto que o controle descendente não foi observado. Quanto à dinâmica dos organismos planctônicos e das variáveis limnológicas associados ao perfil de profundidade, a Lagoa Mangueira não apresentou estratificação das variáveis e consequentemente das comunidades planctônicas, resultado relacionado a uma possível característica de mistura completa da massa d’água, mesmo com ventos de baixa intensidade. As comunidades planctônicas apresentaram maior densidade durante o inverno, direcionadas pela maior disponibilidade de nitrogênio e fósforo. / Bacterioplankton is one of the groups of organisms responsible for the remineralization of nutrients in aquatic ecosystems, as well as a producer of biomass through the microbial loop. Understanding the dynamics of this community due to the thermal variation, resource availability and predation pressure may provide data to assist in the management of water resources through the application of that knowledge or direct subsidies in the interpretation of the results of simulations using ecological models. This work aimed to verify the existence of spatial and temporal heterogeneity in bacterial community structure, density, biomass and richness of morphotypes in Mangueira Lake, as well as identify the limnological variables that drive these patterns. We evidenced the presence of temporal heterogeneity, seasonal and spatial dynamics of bacterioplankton associated with limnological characteristics. The temperature and nutrient availability were the main variables that regulated the planktonic communities, algal biomass, bacterioplankton and zooplankton. There was lateral control, competition for nutrients, between the producing communities. The top down control, predation, was shown to have important effects on the bacterioplankton, more specifically on the coccus morphotype during the summer and winter, and this controlled community in bottom up controled during the fall and spring, mainly nitrogen. During the winter, the community had a significant reduction in bacterial density and biomass, and this response may be related to low water temperatures. Morphotype coccus was the main producing biomass and higher density in the lake. Important spatial heterogeneity was observed at Mangueira Lake for the abiotic variables, whereas the northern and southern regions had the highest spatial differentiation, influenced by the size of the lake. Total phosphorus and total organic carbon regulated bacterial community in the north of the lagoon, especially coccus morphotypes, curved and ‘others’. Among the areas of the lake, the west border and east were the most different depending on the availability of nutrients, especially if the total inorganic carbon. The bacterial density was higher during the summer, autumn and winter in the pelagic region and during the spring on the west border of the lake. The phytoplankton community showed a spatial distribution characterized by higher densities in the north and center of the lake and the pelagic zone. Phosphorus was the main variable limiting communities producing, phytoplankton and bacterioplankton, and bottom up control of these communities, since the top down control was not observed. Considering the dynamics of planktonic organisms and limnological variables associated with the depth profile, the Mangueira Lake did not show stratification of variables and consequently the planktonic communities, the result can be related to a characteristic of complete mixing of water mass, even with low wind intensity. The planktonic communities showed higher densities during the winter, driven by increased availability of nitrogen and phosphorus.
217

Tess evaluateur topologique predictif pour la generation automatique des plans de masse de circuits VLSI

Reis, Ricardo Augusto da Luz January 1983 (has links)
La prédiction de l'organisation topologique du plan de masse d'un circuit VLSI complexe est très importante pour sa conception. Cette thèse présente une étude sur les proprietés statistiques des dessins des masques des principaux blocs constituant un circuit intégré. Un outil prototype d'évaluation topologique est également présenté. Cet outil donne une évaluation de la forme et de la taille de ces blocs, à partir de leurs spécifications fonetionelles. Il est composé par un ensemble de sousprogrammes d'évaluation spécialisés pour les différents types de blocs fonetionnels qui peuvent constituer un circuit VLSI. / The prediction of the floor plan topological organization in the design process of a complex VLSI circuit is very important. This thesis presents a study about statistical properties of the main blocks that compose an integrated circuit. A prototype tool for topological evaluation is also presented. This tool provides an evaluation of the shape and size of these blocks from their functional specifications. It is composed of a set of evaluation rotines specialized for the different functional blocks which may constitute a VLSI circuit.
218

O papel de macrófitas submersas na estrutura e interações entre fitoplâncton e zooplâncton em reservatórios

ROCHA, Cacilda Michele Cardoso 29 February 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-05-02T13:54:54Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação_Cacilda Rocha.pdf: 2113838 bytes, checksum: 349b3a96b2897b76b15485e6fd1e6f54 (MD5) / Made available in DSpace on 2017-05-02T13:54:54Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação_Cacilda Rocha.pdf: 2113838 bytes, checksum: 349b3a96b2897b76b15485e6fd1e6f54 (MD5) Previous issue date: 2016-02-29 / CAPES / Macrófitas submersas promovem atributos das comunidades zooplanctônicas mediante estrutura física, transparência da água, habitat, e abrigo de predadores. Enquanto competem por luz e nutrientes, afetando negativamente o crescimento do fitoplâncton atuando nas interações de controle base-topo e promovendo efeito de controle topo-base do zooplâncton. Pouco foi investigado sobre o papel da vegetação submersa nas interações do zooplâncton e fitoplâncton em áreas sobre influência de reservatório no semiárido brasileiro. Nesse sentido, de maneira a identificar principais lacunas e perspectivas para estudos futuros sobre as macrófitas e interações tróficas enfatizando buscas por estudos realizados na América do Sul, realizamos uma análise cienciométrica, e acreditamos que o número de artigos na área exibirá uma tendência crescente ao longo dos anos, onde a América do Sul apresentará participação significativa tanto no número de publicações quanto na cooperação internacional. Além disso, com a finalidade de investigar se nas áreas com pressões pelos usos em reservatório e solo, plantas submersas são afetadas positivamente, e estruturam riqueza e abundância para o zooplâncton, e suas interações afetam negativamente o fitoplâncton durante quatro períodos, coletamos evidências de efeitos de controle base-topo e topo-base de macrófitas sobre o plâncton. Para tanto, comparamos atributos de comunidades e nutrientes dissolvidos em bancos de plantas na zona litorânea e centros correspondendo à pelágica. Para análise Cienciométrica, acessamos publicações usando base de dados internacional entre 1980 a 2015. A coleta do material no campo mediante navegação pelas áreas em distâncias superiores de 3.5km, com coletas simultâneas da cobertura vegetal, comunidades planctônicas e nutrientes nitrogenados e fósforo total dissolvido. Áreas de cobertura das plantas submersas foram estimadas por medição da proporção de presença e ausência de espécies em 24 pontos em transectos paralelos às margens em área superior a 3.5 km. Coletamos 24 amostras do fitoplâncton e de nutrientes. Para o zooplâncton, realizamos amostragem composta da coluna d’água na vertical e horizontal através de arrastos totalizando 48 amostras. A Cienciometria mostrou que o número de pesquisas sobre essas interações tróficas cresceram nos últimos anos na América do Sul, com contribuições do Brasil, Argentina e Uruguai. O conhecimento sobre as interações tróficas em tem norteado abordagens técnicas e pesquisas científicas em países temperados para melhorar a qualidade da água e restaurar lagos e reservatórios eutrofizados, mas a América do Sul avançou pouco. Constamos que o maior volume de artigos indexados tratou sobre a dinâmica e estrutura das assembléias aquáticas, teias e interações tróficas, para as quaias reservatórios e áreas alagadas receberam pouca atenção. Grande número de estudoscontemplam toda comunidade aquática e interações entre macrófitas, fitoplâncton zooplâncton e peixes. Com relação à pesquisa de campo, a macrófitas ocorreram em alta densidade e cobertura vegetal em 12 pontos por baía (60%; 70%) a diferentes profundidades (2m a 6m). Nas baías, fósforo (médias= 0.03 e 0.05 mg/L) e nitrogênio (0.4 e 0.9 mg/L) apresentaram baixas concentrações. A transparência de Secchi foi alta nas duas baías (>3.8). O fitoplâncton teve riqueza de 17 táxons, dos quais Cyanophyta e Bacillariophyta foram mais representativos. Baixas densidades registradas refletiram nos baixos valores clorofilaa (médias= 9 e 12 µg/l). O zooplâncton apresentou alta dissimilaridade na riqueza (97 spp.) dos Rotifera, Cladocera e Copepoda e abundância relativa, com densidades variando significativamente na zona pelágica (24 a 2013 ind./m³) e litorânea (28 a 1260 ind./m³) de ambas as baías. Nesse contexto, confrontando esses resultados com os dados encontrados da vegetação, juntamente com as baixas concentrações de nutrientes dissolvidos, clorofila-a e alta transparência da água (Secchi), há forte indício da ocorrência de interações com controles base-topo e topo-base sobre o fitoplâncton. Nossos dados suportam a hipótese de prováveis efeitos dessas interações estejam contribuindo para a manutenção das condições de transparência da água nas baías, favorecendo baixa riqueza e biomassa algal. Uma vez que o conhecimento sobre as interações tróficas, particularmente as que ocorrem em cascata tem sido desenvolvido com sucesso em na reestruturação e restauração da qualidade da água em diversos países. Esta pesquisa contribui para o conhecimento das interações mediadas pelas macrófitas, sobre o zooplâncton e fitoplâncton em áreas de influência de reservatórios. Contudo, estudos na área das interações tróficas mediadas pelas macrófitas poderão ser direcionados de maneira a atenuar assimetrias internacionais, encorajando o aumento da produtividade científica na América do Sul. Esforços para restaurar as baías no entorno do reservatório no Brasil poderão ser despendidos usando técnicas combinadas para aumentar a qualidade da água e incrementar atributos das comunidades aquáticas. / Submerged macrophytes promote attributes of planktonic communities by physical structure, water transparency, habitat, and shelter from predators. As they compete for light and nutrients, affecting negatively the phytoplankton growing, mediated bottom-up and topdown control interactions of zooplankton. Little has been investigated on the role of submerged vegetation in the interactions of zooplankton and phytoplankton in areas of reservoir influence in the Brazilian semiarid region. In order to identify major gaps and perspectives for future studies of macrophytes and trophic interactions, emphasizing searches for studies in South America, we conducted a scientometric analysis. We believe that the number of articles in the area show an increasing tendency to over the years, where South America will present significant participation in both the number of publications and in international cooperation. In order to investigate the impact of land use areas surrounding reservoir in submerged plants on planktonic communities, during four periods, we collect evidence of bottom-up and top-down controls of macrophyte on plankton. Our hypothesis is that the macrophytes are affected positively in that areas, and at the same time, can provide structure for richness and abundance to zooplankton and their interactions affect phytoplankton negatively. In the field we compare attributes of communities and dissolved nutrients in plant beds in the littoral and pelagic zones. For scientometrical analysis, we access publications using international database from 1980 to 2015. In the field, the samples were collected by boat, where greater distances with simultaneous sampling of vegetation, plankton communities and nitrogenous nutrients and total phosphorus dissolved. The submerged plant coverage areas were estimated by reducing the proportion of presence and absence of species in 24 points in parallel transects an area greater than 3.5 km. We collected 24 samples of phytoplankton and nutrients. For zooplankton, carry out sample composed of the water column vertically and horizontally, through hauls totaling 48 samples. The scientometrical analysis results showed that the number of trophic interactions researches grown in recent years in South America, with contributions from Brazil, Argentina and Uruguay. We found that the highest volume of indexed articles deals with the dynamics and structure of aquatic assemblages, webs and trophic interactions. Reservoirs and wetlands have received little attention. The large number of studies includes all aquatic community and interactions between macrophytes, phytoplankton, zooplankton and fish. Macrophytes occurred in high density and vegetation cover at 12 points per bay (60%; 70%) at different depths (2m to 6m). In the bays, phosphorus (mean = 0.03 and 0.05 mg / L) and nitrogen (0.4 and 0.9 mg / L) had lower concentrations. We found high Secchi transparency (>3.8) for both bays. The phytoplankton richness was 17 taxa, of which Cyanophyta Bacillariophyta were most representative. Low densities recorded reflected in lower values Chlorophyll-a (mean = 9.12 µg/l). Zooplankton showed high dissimilarity in the richness (97 spp.) of rotifers, Cladocera and Copepoda, with relative abundance. Densities varying significantly in the pelagic (24-2013 ind./m³) and littoral zones (28-1260 ind./m³) of both the bays. In this context, comparing these results with data from the vegetation, along with low concentrations of dissolved nutrients, chlorophyll-a and high water transparency, there is strong evidence of the occurrence of macrophytes and zooplankton interactions with bottomup and top-down controls on phytoplankton. Our data support the hypothesis that probably, effects of these interactions are contributing to the maintenance of conditions of water transparency, favoring low richness and algal biomass. The knowledge of trophic interactions, particularly which occur in cascades, has been successfully developed in the restructuring and restoration of water quality in several countries. This research brings to contributes to the knowledge of macrophytes, zooplankton and phytoplankton interactions in areas influenced by reservoirs. However, studies in the area of trophic interactions mediated by macrophytes may be directed in order to mitigate international asymmetries by encouraging increased scientific productivity in South America. Efforts to restore the bays around the reservoir in Brazil may be spent using combined techniques to increase the quality water and increase attributes of aquatic communities.
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Faktorer som styr val av data warehouse arkitektur : Inmon vs. Kimball / Factors that control the choice of data warehouse architecture : Inmon vs. Kimball

Karim, Mona January 2017 (has links)
Data warehouse (DW) solutions are becoming increasingly popular to implement in different organizations. There are a variety of motivational factors for activities to acquire DW, among other things, it helps with analyzes and decision making in the business to gain for an example competitiveness. DW projects are expensive projects that require a lot of resources from the organization side. However, more and more DW projects fail and are not optimal for business purposes. Before the organization implements a DW, it is important to choose architecture based on, i.e. a data model for how data is stored and structured in the DW. The two dominant architecture models are top-down as Inmon presented in the 90s and bottom-up who Kimball introduced after Inmon announced his model.  Both Inmon and Kimball have their own philosophies and models for how a DW solution should be model. Organization dilemma is choosing one or the other performance. The choice depends on many factors and considerations. There are also significant philosophical debates, obstacles, also pros and cons for choice of the data warehouse architecture (Lawyer & Chowdhury, 2004). Therefore, this study should demonstrate which factors govern the choice of architecture using a literature study comparing these models. The result shows that Inmon's top-down approach handles factors like data quality, how data can be integrated from different source systems, flexibility, metadata management, and handle data sources and ETL better than Kimball's bottom-up approach. Kimball's architecture model focuses more on factors such as performance and end-user interaction. The results also show that the Kimball model is easier and faster to implement. / Data warehouse (DW) lösningar blir allt mer populära att implementera hos verksamheter. Det finns en mängd motivationsfaktorer för verksamheter att inskaffa DW, bland annat att systemet hjälper med analyser och beslutsunderlag i verksamheten för att erhålla exempelvis konkurrenskraft. DW-projekt är dyra projekt som kräver en hel del resurs från verksamhets sida. Dock misslyckas allt fler sådana projekt och resulterar i att inte vara optimala för verksamhetsändamålen.  Innan verksamheten implementerar ett DW är det viktigt att välja en arkitektur att utgå ifrån, alltså en datamodell för hur data ska lagras och struktureras i DW. De två dominerande arkitekturmodellerna är top-down som Inmon presenterade på 90-talet och bottom-up som Kimball introducerade efter att Inmon presenterat sin modell.   Både Inmon och Kimball har sina egna filosofier och modeller för hur en DW-lösning ska se ut. Dilemmat för verksamheter handlar om att välja det ena eller det andra utförandet. Valet beror på många faktorer och överväganden. Det finns också betydande filosofiska debatter, hinder, och för-och nackdelar med valet av ett data warehouse arkitektur (Lawyer & Chowdhury, 2004).Följaktligen skall denna studie påvisa vilka faktorer som styr val av arkitektur genom att tillämpa en litteraturstudie där dessa modeller jämförs.  Av resultatet framgår att Inmons top-down approach hanterar faktorer som datakvalitet, hur data kan integreras från olika källsystem, flexibilitet, metadatahantering samt att den hanterar datakällor och ETL på ett bättre sätt än Kimballs bottom-up approach. Kimballs arkitektursmodell fokuserar mer på faktorer som prestanda och slutanvändarinteraktion. Av resultatet framgår även att Kimballs modell implementeras enklare och snabbare.
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An analysis concerning three organisations work with reducing child labour : – A case study within Peru’s mining industry

Sheikholeslamzadeh, Sanaz, Bergvall Bark, Marie January 2008 (has links)
This thesis aim to describe and analyze different organisations’ work with reducing child labour. In order to understand the complex matter of child labour, a case study concerning children’s situation within the mining industry in Peru has been made. The first part of the thesis has been designed to be an introduction to the matter, with a description of the mining industry in Peru and the situation of child labour. The two following parts are more analytic in character. The second and third part discusses how the Millennium Development Goals (MDGs) can be used as an instrument of reducing child labour. Further, top down and bottom up-theories will be discussed as different approaches and working methods for organisations. In addition to find the answers to our questions, interviews have been conducted with employees of the organisations (ILO, UNICEF and Save the Children), articles and literature have been analyzed and finally Internet have contributed with information about child labour, Peru, the organisations, theories and the MDGs. This study claims that child labour is a complex matter and one possible solution to reduce it can be through promoting education. This can only be viable if organisations work together with governments, using a combination of top down and bottom up approaches.

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