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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.
171

Cooperação Sul-Sul : análise dos acordos de preferência comercial do Brasil no IBAS

D’Andrea, Luciano Romano January 2014 (has links)
Este projeto tem por objetivo analisar o potencial comercial brasileiro no contexto da Cooperação Sul-Sul, através do estudo dos Acordos Comerciais do Brasil com a África do Sul e a Índia (Mercosul – SACU e Mercosul – Índia). O presente trabalho possui dois propósitos principais – analisar o status quo e o perfil dos acordos comerciais em pauta entre o Brasil, África do Sul e a Índia e sequencialmente verificar o potencial de aprofundamento do atual Acordo Mercosul – Índia rumo a uma futura Área de Livre Comércio como forma efetiva de fortalecimento econômico no contexto da estratégia brasileira frente aos países do IBAS e da Cooperação Sul-Sul. Para estudar os Acordos de Preferência Comercial selecionados, se utilizará a metodologia multicritério de análise das ofensividades e sensibilidades dos principais produtos brasileiros exportados e importados com estes mercados, o grau de abrangência, profundidade e a cobertura de tais acordos. Por fim, pretende-se inferir considerações gerais sobre o fortalecimento comercial, econômico e político no âmbito da Cooperação Sul-Sul que se poderia obter a partir da ampliação de tais acordos. / This project aims to analyze the Brazilian commercial potential in the context of South-South Cooperation, through the study of Brazil's Trade Agreements with South Africa and India (Mercosur - SACU and Mercosur - India). This work has two main purposes - to analyze the ‘status quo’ and the profile of trade agreements at issue between Brazil, South Africa and India, and sequentially verify the potential of deepening the current Mercosur Agreement - India towards a future Free Trade Area as an effective form of economic empowerment in the context of the Brazilian strategy at IBSA countries and in the South-South Cooperation. To study the selected trade preference agreements, the methodology approach to be used will be the multiple-criteria analysis of offensiveness and sensitivities of the main Brazilian products exported and imported with these markets, the degree of breadth, depth and coverage of such agreements. Finally, the intention is to infer general considerations on the commercial, economic and political empowerment within the framework of South-South cooperation that could be obtained from the expansion of such agreements.
172

Jak ptáci poznávají predátory - význam úplnosti vizuální informace / How do the birds recognize predators - importance of complete visual information

TVARDÍKOVÁ, Kateřina January 2009 (has links)
Pair-wise preferential experiments were used to reveal dangerous predator differentiation and ability of amodal completion by four tit species. Firstly was revealed that the tits{\crq} behaviour towards the feeder was in agreement with predictions of the dynamic risk assessment theory. The presence of any predator at the feeder lowered the number of visits to the feeder. Likewise, the tits evaluated the sparrowhawk as more dangerous than the kestrel because its presence lowered the number of visits more than the kestrel. Secondly, we observed tits{\crq} reactions to both partly occluded and amputated dummy of sparrowhawk in two different treatments (torsos vs. complete dummy of pigeon, torsos vs. complete dummy of sparrowhawk). All birds clearly classified both torsos as ``full-featured{\crqq} predators and kept away of them when pigeon on the second feeder. However, when sparrowhawk was presented on the second feeder, number of visits to amputated predator was higher than to occluded one. Birds risked arriving to ``utter{\crqq} amputated torso while the fear of ``full-featured{\crqq} occluded torso stayed without change when second feeder did not provide safe alternative. Such discrimination between torsos needs ability of amodal completion.
173

Jak ptáci poznávají predátory - význam úplnosti vizuální informace / How do the birds recognize the predators - importance of complete visual information

TVARDÍKOVÁ, Kateřina January 2009 (has links)
Pair-wise preferential experiments were used to reveal dangerous predator differentiation and ability of amodal completion by four tit species. Firstly was revealed that the tits{\crq} behaviour towards the feeder was in agreement with predictions of the dynamic risk assessment theory. The presence of any predator at the feeder lowered the number of visits to the feeder. Likewise, the tits evaluated the sparrowhawk as more dangerous than the kestrel because its presence lowered the number of visits more than the kestrel. Secondly, we observed tits{\crq} reactions to both partly occluded and amputated dummy of sparrowhawk in two different treatments (torsos vs. complete dummy of pigeon, torsos vs. complete dummy of sparrowhawk). All birds clearly classified both torsos as ``full-featured{\crqq} predators and kept away of them when pigeon on the second feeder. However, when sparrowhawk was presented on the second feeder, number of visits to amputated predator was higher than to occluded one. Birds risked arriving to ``utter{\crqq} amputated torso while the fear of ``full-featured{\crqq} occluded torso stayed without change when second feeder did not provide safe alternative. Such discrimination between torsos needs ability of amodal completion.
174

Impactos económicos de los arreglos preferenciales comerciales: una síntesis teórica

Tello, Mario D. 10 April 2018 (has links)
El presente trabajo sintetiza las proposiciones teóricas relevantes para el análisis de los impactos económicos de los arreglos preferenciales comerciales (APC) que caracterizan a los procesos de apertura comercial implementados por las economías, desarrolladas y en desarrollo, en las últimas dos décadas. Estos arreglos se agrupan en tres tipos: los unilaterales (APCU), los regionales (APCR) y los multilaterales (APCM). El trabajo resume, además, los argumentos y proposiciones teóricas que responden a dos interrogantes. La primera, desde la perspectiva de una economía individual, ¿cuál de estos arreglos, o formas de estrategia comercial, origina los mayores beneficios económicos para una economía? Asumiendo que los APCM son la mejor opción de política comercial para todos los países del mundo que acuerdan estos arreglos, la segunda interrogante es ¿en qué medida los APCU, y en particular los APCR contribuyen (building blocks or friends), obstruyen (stumbing blocks or foes) o convergen (stepping stones) o no (strangers) a los APCM?---The present work synthesizes the relevant theoretical propositions for the analysis of the economic impacts of the preferential trade arrangements (PTAs) which have been part of the trade liberalization process implemented in the last two decades by developed and developing economies. These arrangements are divided in three groups of arrangements: i) unilateral (UPTAs), ii) regional (RPTAs) and iii) multilateral (MPTAs). In addition, this paper addresses two questions. The first one, (from the perspective of an individual economy) which of these arrangements benefit the most for an economy?. The second, to what extent UPTAs and especially RPTAs, contribute (or are \’ building blocks or friends\’), obstruct (or are \’stumbling blocks or friends\’) or converge (or are \’stepping stones\’) or not (\’strangers\’) to the PTAs?
175

Ecologia trófica de Conopophaga lineata (Wied, 1831) e Conopophaga melanos (Vieillot, 1818) (Aves: Conopophagidae): aspectos das relações de nicho e seleção de presa

Souza, Ludemila Martins de 27 April 2017 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2017-10-09T20:17:53Z No. of bitstreams: 1 ludemilamartinsdesouza.pdf: 1476036 bytes, checksum: 13c93142a0ac36c1cce3f43d89f846ca (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-10-10T12:20:05Z (GMT) No. of bitstreams: 1 ludemilamartinsdesouza.pdf: 1476036 bytes, checksum: 13c93142a0ac36c1cce3f43d89f846ca (MD5) / Made available in DSpace on 2017-10-10T12:20:05Z (GMT). No. of bitstreams: 1 ludemilamartinsdesouza.pdf: 1476036 bytes, checksum: 13c93142a0ac36c1cce3f43d89f846ca (MD5) Previous issue date: 2017-04-27 / Dados sobre a ecologia alimentar de duas aves de sub-bosque foram coletados na Reserva Biológica Municipal do Poço D’anta, Juiz de Fora – MG, sudeste do Brasil. Conopophaga lineata e Conopophaga melanops são encontradas ocorrendo em simpátria em algumas localidades da Região Sudeste. Estudos com espécies aparentadas e simpátricas podem ser úteis no sentido de avaliar a influência do nicho sobre co ocorrência e co-existência. Durante as amostragens utilizando redes ornitológicas obtivemos 29 capturas de 25 indivíduos de C. lineata, e 28 capturas de 21 indivíduos de C. melanops. Na triagem das amostras fecais de C. lineata e C. melanops foram encontrados, respectivamente, 310 e 276 itens. C. lineata consumiu predominantemente Formicidae (53,5%), Coleoptera (6,8%). Entretanto, o índice alimentar (IA) de Coleoptera (7,47) ficou abaixo de outros grupos como Formicidae (68,2) e Araneae (8,80). C. melanops consumiu altas proporções de Formicidae (23,2%), Coloptera (12,3%), Orthoptera (11,6%) e Isoptera (11,2%), embora em termos de IA o predomínio tenha sido de Formicidae (24,66) e Coleoptera (20,14). A sobreposição de nicho entre as espécies foi maior que o esperado (observado = 0.723). Apesar das diferenças nas proporções dos tipos de artrópodes consumidos não foram suficientes para revelar separação de seus nichos alimentares. Embora se encontrem na literatura que C. lineata seleciona tanto tipo de presas quanto artrópodes maiores que 5 mm em proporções acima do esperado pelo acaso, assim como foi observado para C. melanops predação preferencial sobre alguns táxons. Os resultados encontrados demonstram que, em alguns casos, os padrões ecológicos das respostas das aves aos recursos encontrados no ambiente podem ser diferentes daqueles encontrados em outras regiões. / Data on the food ecology of two understory birds were collected at the Municipal Reserva Biológica Municipal do Poço D’anta, Juiz de Fora – MG, Southeastern Brazil. Conopophaga lineata and Conopophaga melanops are found occurring in sympatry in some localities of the Southeast Region. Studies with related and sympatric species may be useful in assessing the influence of the niche on co-occurrence and co-existence. During the samplings using ontological networks were carried out 29 catches of 25 individuals of C. lineata, and 28 catches of 21 individuals of C. melanops. In the sorting of the fecal samples of C. lineata and C. melanops were found, respectively, 310 and 276 items. C. lineata consumed predominantly Formicidae (53.5%), Coleoptera (6.8%). However, Coleoptera dietary index (AI) (7.47) was below other groups such as Formicidae (68.2) and Araneae (8.80). C. melanops consumed high proportions of Formicidae (23.2%), Coloptera (12.3%), Orthoptera (11.6%) and Isoptera (11.2%), although in terms of AI the predominance was Formicidae (24.66) and Coleoptera (20.14). The niche overlap between species was higher than expected (observed = 0.723). Although differences in the proportions of the types of arthropods consumed were not sufficient to reveal separation of their food niches. Although it is found in the literature that C. lineata selects both prey and arthropod species larger than 5 mm in proportions above that expected by chance, just as it was observed for C. melanops preferential predation on some taxa. The results show that, in some cases, the ecological patterns of bird responses to the resources found in the environment may be different from those found in other regions.
176

Subsurface fluxes of mass and energy at the accumulation zone of Lomonosovfonna ice cap, Svalbard

Marchenko, Sergey January 2018 (has links)
Glaciers cover ca 10% of the Earth's land and are found in the high altitudes and latitudes. They are important components of environmental systems due to the multiple feedbacks linking them with the atmosphere, hydrosphere and periglacial landscapes. The cold sloping surfaces of glaciers change the patterns of atmospheric circulation at different scales and at the same time glaciers are largely controlled by climate. They are commonly used as climatic archives for reconstruction of the past environmental changes based on evidences from the areas affected by glaciation at the moment and in the past. Glaciers are the largest fresh-water reservoirs on our planet and runoff thereof significantly affects the global sea level and life in glaciated catchments. However, melt- and rain-induced runoff from glaciers greatly depends on the subsurface conditions which thus need to be taken into account, particularly in a changing climate. This thesis focuses on the processes of subsurface mass and energy exchange in the accumulation zones of glaciers, which are largely driven by the climate at the surface. Results are largely based on empirical data from Lomonosovfonna ice cap, Svalbard, collected during field campaigns in 2012-2017. Observations of subsurface density and stratigraphy using shallow cores, video records from boreholes and radar surveys returned detailed descriptions of the snow and firn layering. The subsurface temperature data collected using multiple thermistor strings provided insights into several subsurface processes. The temperature values measured during three summer seasons were used to constrain the suggested parameterization of deep preferential water flow through snow and firn. The part of data recorded during the cold seasons was employed for an inverse modelling exercise resulting in optimized values of effective thermal conductivity of the subsurface profile. These results are then used to compute the subsurface water content by comparing the simulated and measured rates of freezing front propagation after the melt season in 2014. The field observations and quantitative estimates provide further empirical evidences of preferential water flow in snow/firn packs at glaciers. Results presented in the thesis call for implementation of description of the process in layered models simulating the subsurface fluxes of energy and mass at glaciers. This will result in a better understanding of glacier response to the past and future climatic changes and more accurate estimates of glacier runoff. / Stability and Variations of Arctic Land Ice (SVALI)
177

Justifying Preferential Treatment - Preferential Policies in Theory and Reality

Bruhagen, Åsa January 2006 (has links)
<b>Background and problem:</b> It is important for a policy aiming at overcoming discrimination to be justifiable as just or as creating justice. When a policy is implemented lacking such qualities it is argued to be unjust, which creates a problem. During the last decades there has been massive immigration to the Western countries from countries marked by war and disaster. This has created problems of integration into the “new” society, and the use of preferential policies has become increasingly topical. Whether or not the use of preferential policies is a just method is the basis of this thesis. <b>Aim</b>: The aim of this thesis is to study the concept of preferential policies in an impartial perspective of fairness. By impartial it is meant to present facts speaking both for and against preferential policies as being just. The main question of this thesis is whether or not preferential treatment is a just method to create equality within the society. <b>Method</b>: A research method of textual analysis has been used combined with an analysis of structure of arguments. <b>Theoretical framework</b>: First, definitions of discrimination and preferential policies as such are focused upon in the third chapter. Second, the concept of social justice and its connection to preferential policies is treated. The question if preferential policies should be directed towards individuals or groups is a central question in the debate and it will demand its space in this thesis. Here the importance of merit will be discussed. The section about individuals and groups will be followed by a section discussing the importance of ethnic diversity which will be followed by a comparison of the development of preferential policies in the USA and Sweden. Last, there will be a section where an attempt to generalize between arguments is made. <b>Conclusions and Discussion</b>: In this part a conclusion and a discussion will be presented. Here conclusions will be drawn from the gathered material. Finally there will be a discussion on the subject and of how the research procedure has proceeded.
178

Integrated management of groundwater and dependent ecosystems in a Finnish esker

Rossi, P. M. (Pekka M.) 27 May 2014 (has links)
Abstract Groundwater, a key part of the hydrological cycle, is under increasing pressure from different land uses and changing climate. However, less attention has been paid to integrated groundwater management than surface waters. This thesis combined hydrological and socio-economic research for the case study of the Rokua esker aquifer in order to update current concepts of groundwater management. The Rokua area contains groundwater-dependent lakes and a periodic water level decline has raised concerns about the future of these lakes. Peatland drainage in the vicinity of the aquifer has been accused of changing the aquifer conditions. Groundwater discharge from the esker aquifer to drained peatland was studied to identify relevant hydrological processes for groundwater-surface water interactions. The results revealed a connection between the aquifer and the peatland whereby groundwater can enter the ditches through seepage or preferential flow. Modeling was used to determine critical factors in the management of the esker aquifer-peatland system. The results showed that climate and land use can affect esker groundwater, while peatland drainage in the vicinity can have similar impacts to groundwater abstraction and drought. Peatland restoration by filling in drainage ditches could possibly restore the aquifer groundwater levels. However, for the Rokua aquifer, which will possibly experience less severe dry periods in the future, extensive drainage restoration is currently too major, uncertain, and expensive a measure relative to the expected benefits. Multi-criteria decision analysis was used to identify ways of facilitating stakeholder involvement and learning in groundwater management. The results obtained with this participatory process confirmed that it can foster learning on complicated groundwater issues and collaboration in a process encompassing disputes and diverse interests. The decision analysis process led to the initiation of dialogue on more integrated management, where the preferences of all stakeholders were discussed and taken into account. Overall, this thesis shows how different aspects of aquifer management, such as land use, climate, ecological and economic values, and stakeholder preferences, can all be taken into account using a combined method which reduces the mistrust between opposing interests through research and information, resulting in more robust future planning. / Tiivistelmä Pohjaveteen, hydrologisen kierron avainosaan, kohdistuu kasvavia paineita eri maankäytön muodoista ja ilmastonmuutoksesta. Pohjaveden hallintaan ei kuitenkaan ole kiinnitetty tarvittavaa huomiota. Tässä väitöstyössä yhdistettiin hydrologista ja sosioekonomista tutkimusta Rokuan harjualueella pohjaveden hallintakonseptin päivittämiseksi. Rokuan alueella on useita pohjavedestä riippuvaisia järviä, joiden vedenpinta on kausittain laskenut voimakkaasti. Pintojen lasku on kasvattanut paikallisten huolta järvien tilasta. Harjua ympäröivät metsäojitetut turvemaat, ja ojituksia on syytetty pohjaveden tilan ja sitä kautta myös järvien tilan heikkenemisestä. Työn ensimmäisessä osassa tutkittiin pohjaveden hydrologisia purkautumisprosesseja harjun pohjavesiesiintymästä ojitetulle suoalueelle. Tulokset osoittivat hydraulisen yhteyden akviferin ja turvemaan välillä: pohjavesi pääsi purkautumaan metsäojiin joko suotautumalla tai turpeen kaksoishuokoisuusrakenteiden kautta. Seuraavassa vaiheessa työtä pohjavesimallinnusta käytettiin määrittämään kriittisiä pohjaveden tilaan vaikuttavia tekijöitä pohjavesi-turvemaa-systeemissä. Mallinnustulosten perusteella niin ilmasto kuin maankäyttökin vaikuttavat kumpikin suoraan pohjaveden pinnankorkeuden tilaan. Turvemaiden ojituksilla pohjavesialueella voi olla samoja vaikutuksia pohjaveden pinnankorkeuden tasoihin kuin pohjaveden otolla tai kuivilla kausilla. Turvemaiden ennallistaminen ojia täyttämällä voi osittain palauttaa vedenpinnan tasoja pohjavesialueella. Rokuan harjualueen tapauksessa suuren mittakaavan oja-alueiden ennallistaminen todettiin kuitenkin liian epävarmaksi ja kalliiksi toimenpiteeksi hyötyihin nähden, varsinkin jos kuivien kausien vaikutus suurilla harjualueilla heikkenee tulevaisuudessa sademäärien kasvun myötä. Työn kolmannessa osassa käytettiin monitavoitearviointia eri sidosryhmien osallistamiseen ja oppimiseen pohjavesien hallinnassa. Osallistavasta prosessista saadut tulokset vahvistivat, että menetelmää voidaan käyttää oppimisen edesauttamiseen vaikeissa pohjavesiasioissa sekä yhteistyön muodostamiseen ristiriitaisessa ja monimutkaisessa tapauksessa. Monitavoitearvioinnin prosessi johti keskustelun avaukseen yhtenäisemmän suunnittelun puolesta, joka ottaa huomioon eri sidosryhmien näkökulmat ja tuo ne osaksi keskustelua. Tämä väitöstyö osoitti miten eri pohjavesialueen hallintaan tarvittavat näkökulmat, kuten maankäyttö, ilmasto, ekologiset ja ekonomiset arvot, sekä sidosryhmien mielipiteet voidaan kaikki ottaa huomioon yhdistämällä eri metodeja. Näin tutkimuksella ja informoinnilla vähennetään epäluottamusta eri intressitahojen välillä ja luodaan pohja vakaammalle pohjavesialueiden tulevaisuuden suunnittelulle.
179

Analyse des processus d'écoulement lors de crues à cinétique rapide sur l'arc méditerranéen / Flash food modelling for a better understanding of hydrological processes in the Mediterranean

Douinot, Audrey 12 December 2016 (has links)
L'objectif de la thèse est d'améliorer la compréhension des processus hydrologiques lors des événements de crues éclair. Se basant sur un modèle existant (MARINE), l'étude se concentre sur les processus internes au sol. Une étape préliminaire permet, à partir de l'analyse des données, de confirmer l'activité du socle rocheux durant les crues éclair. Une analyse structurelle de MARINE est réalisée, afin de connaître la sensibilité des flux de subsurface aux choix structurels. Une nouvelle modélisation, plus robuste et intégrant explicitement une représentation des roches altérées, est mise en place. Supposant des chemins préférentiels à l'interface sol/roche, le modèle donne une bonne reproduction des bassins sédimentaires. Sur les bassins granitiques, il sous-estime les récessions et, en conséquence, les éventuels seconds pics de crue, montrant la nécessité de représenter des flux significatifs sur ces bassins, y compris dans la zone altérée. / The purpose of this thesis is to improve the knowledge of hydrological processes during flash flood events using rainfall-runoff modelling. The project focuses on hydrological processes occurring into soil and subsoil horizons. A preliminary data analysis corroborates the activity of the weathered bedrock during flash floods. The hydrological response, simulated by the MARINE model, is then investigated to detect the sensitivity of subsurface flow processes to model assumptions. It leads to several modifications of the model structure in order to make it more robust. Moreover a two-layered soil column is implemented to explicitly integrate the activity of the weathered bedrock into the model. Assuming preferential path flows at the soil-bedrock interface, the model performs well on sedimentary watersheds, but underestimate recession curves and second flood peaks on granitic ones, showing the need to simulate as well significantcontribution from the weathered bedrock.
180

Phosphorus in Preferential Flow Pathways of Forest Soils in Germany.

Julich, Dorit, Feger, Karl-Heinz 27 March 2017 (has links)
The transport of nutrients in forest soils predominantly occurs along preferential flow pathways (PFP). This study investigated the composition of phosphorus (P) forms in PFPs and soil matrix in several temperate beech forests with contrasting soil P contents in Germany. The PFPs were visualized using dye tracer experiments. Stained and unstained soil was sampled from three profile cuts per plot and analyzed for P fractions. The results show that labile P concentrations were highest in the O-layer and had the same range of values at all sites (240–320 mg·kg−1), although total P (TP) differed considerably (530–2330 mg·kg−1). The ratio of labile P to TP was significantly lower in the P-rich soil compared to the medium and P-poor soils. By contrast, the ratio of moderately labile P to TP was highest at the P-rich site. The shifts in P fractions with soil depth were generally gradual in the P-rich soil, but more abrupt at the others. The contents of labile and moderately labile P clearly differed in PFPs compared to soil matrix, but not statistically significant. The studied soils are characterized by high stone contents with low potential for P sorption. However, indications were found that labile organically bound P accumulates in PFPs such as biopores.

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