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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.
101

The Zambezi River Basin: Water Resources Management : Energy-Food-Water nexus approach

Sainz, Gabriel January 2018 (has links)
The energy-food-water nexus is of fundamental significance in the goal towards sustainable development. The Zambezi River Basin, situated in southern Africa, currently offers vast water resources for social and economic development for the eight riparian countries that constitute the watershed. Hydropower generation and agriculture are the main water users in the watershed with great potential of expansion, plus urban water supply materialise the largest consumers of this resource. Climate and social changes are pressuring natural resources availability which might show severe alterations due to enhances in the variability of precipitation patterns. This study thus examines the present water resources in the transboundary basin and executes low and high case future climate change incited scenarios in order to estimate the possible availability of water for the period 2060-2099 by performing water balances. Along with projections of water accessibility, approximations on water demands from the main consumer sectors are performed. Results show an annual positive balance for both projected scenarios due to an increase in precipitation during the wet season. They also present a severe increase in overall temperature for the region contributing to a strong increase in evapotranspiration. Projections further inform of an acute increase in water demand for irrigation and urban supply, nevertheless, evaporation from hydropower storage reservoirs continues to exceed water with drawals in volume. Acknowledging the uncertainty contained in this report allows a broader offer of recommendations to be considered when planning for future developments with a sustainable approach. Improvement of hydrological collection systems in the Zambezi basin is indispensable to accomplish a deeper and cohesive understanding of the watershed waterresources. Cooperation and knowledge communication between riparian countries seems to be the right beginning towards social and economic sustainable development for the Zambezi River Basin.
102

Uma educação ambiental como estética da existência e epistemologia dos nexos: a experiência socioeducativa do Projeto Florescer / Enviromental education as an aesthetics of existence and epistemology of nexos: the social and educational experience of the Blossom Project

Maristela Barenco Corrêa de Mello 13 June 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Partindo da constatação da emergência de uma crise ambiental planetária e das várias concepções de Educação Ambiental que têm emergido como tentativas de dialogar com tal crise, a presente tese consiste na postulação e aprofundamento de quatro enunciados expressões de problemáticas teórico-práticas,delineadas na experiência pessoal e profissional interdisciplinar da autora -, aqui apresentados na forma de indagações paradigmáticas, epistemológicas, teórico-filosóficas e político-pedagógicas. O objetivo da presente pesquisa é contribuir com o campo dos processos de educação ambiental comprometidos com os modos de singularização emancipatórios, através de proposições reflexivas que possam evidenciar outras bases epistemológicas, filosóficas e conceituais à Educação. O Enunciado I, tendo como referências, sobretudo, a lógica rizomática, de Deleuze e Guattari, a ecologia dos saberes e as epistemologias do Sul, de Santos, e o conceito de complexidade, de Morin, postula a necessidade de emergência de uma Epistemologia dos Nexos, como conjunto de epistemologias, que nos possibilite restaurar a capacidade perceptiva de leitura do mundo em sua inteligibilidade e sensibilidade relacional, complexa, de conexões com nexos, a partir da problematização de uma herança epistemológica hegemônica que, contra a diversidade epistemológica do mundo, foi tecida com os fios da trama colonialista e ocidental cristã. O Enunciado II postula uma Educação Ambiental comprometida com a diversidade de modos e formas de conhecer, de se envolver e dialogar com a realidade e a vida, para além da racionalidade moderna e o conhecimento científico, tendo como referências, sobretudo, Freire, Santos, Maturana e Leloup. O Enunciado III pretende trazer à reflexão, sobretudo com Guattari, Rolnik e Godoy, a importância dos processos subjetivos como matérias-primas e instâncias de modelização na consolidação dos modelos econômicos, que historicamente tem se mantido invisibilizados dentro dos ideários políticos e educacionais, a serviço de uma ideologia dominante. Para tanto trabalha os conceitos de subjetivação, singularização, micropolítica e perspectivas minoritárias. Finalmente, o Enunciado IV, tomando algumas noções da filosofia a saber, o daimon grego, trazido por Boff, como dimensão interior humana; o compromisso quântico em Zohar, que postula um novo modelo relacional; a noção de afetos na Ética de Espinosa, como encontros que possibilitam a expansão ou diminuição de uma potência de agir; a noção de afirmação da vida, em Nietzsche, enquanto alegria e abundância, como uma estética da existência; e a noção de cuidado de si, de Foucault, como uma prática de autonomia do ser postula a proposição de uma Ética Ambiental, como Estética, comprometida com um fazer artístico de ser humano e de seus modos de existência. Tais enunciados, sistematizados através de uma metodologia qualitativa e cartográfica, serão colocados em diálogo, na forma de um Estudo de Caso, com um projeto social que trabalha com jovens, denominado Projeto Florescer: Arte-educação, Cidadania e Ecologia para Jovens, evidenciando ao campo dos processos de educação ambiental uma diversidade de modos educativos - poéticos, políticos, éticos, estéticos e místicos, capazes de tocar o mundo e o ser humano naquilo que eles têm de mais inédito, inusitado e especial
103

Ambiente virtual utilizando o sensor kinect combinado com avaliação biomecânica para reabilitação dos membros superiores de pacientes acometidos de acidente vascular encefálico / Virtual environment using the kinect sensor combined with a biomechanical evaluation for rehabilitation of the upper limbs of patients suffering from stroke

Carvalhaes, Millys Fabrielle Araujo 23 June 2015 (has links)
Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2016-06-17T17:13:17Z No. of bitstreams: 2 Dissertação - Millys Fabrielle Araújo Carvalhaes.pdf: 4151175 bytes, checksum: 37325a1481b0c779e840016337633c80 (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-06-28T13:16:06Z (GMT) No. of bitstreams: 2 Dissertação - Millys Fabrielle Araújo Carvalhaes.pdf: 4151175 bytes, checksum: 37325a1481b0c779e840016337633c80 (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) / Made available in DSpace on 2016-06-28T13:16:06Z (GMT). No. of bitstreams: 2 Dissertação - Millys Fabrielle Araújo Carvalhaes.pdf: 4151175 bytes, checksum: 37325a1481b0c779e840016337633c80 (MD5) license_rdf: 19874 bytes, checksum: 38cb62ef53e6f513db2fb7e337df6485 (MD5) Previous issue date: 2015-06-23 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / This study proposes a computational tool to support motor rehabilitation of the upper limbs in post stroke patients. This tool was designed to be used in combination with Virtual Environment, which is also being developed at Bioengineering and Biomechanics Laboratory. Thereby, while the virtual environment focus is the patient interaction and immersion through Kinect Xbox 360 sensor, the main goal of this study is a biomechanical analysis of the movements performed by the patients via the data generated by the Kinect during the patient’s interaction with the virtual environment. Furthermore, since Kinect Xbox 360 is not designed for clinical analysis, tests were performed to compare the precision with respect to a standard motion capture system, the Vicon system, considered the gold standard, widely used in laboratories of biomechanics for kinematic analysis of movements. In this respect, statistical tests were used to compare the results of both systems. In addition, vector analysis using the Statistical Parametric Mapping method allowed provided about information about which coordinates had greater influence at the results. / A proposta deste trabalho foi a elaboração e desenvolvimento de uma ferramenta computacional para avaliar o processo de reabilitação motora dos membros superiores de pacientes acometidos de acidente vascular encefálico (AVE) ao utilizar o ambiente virtual (AV) para Reabilitação de Membros Superiores também desenvolvido no Laboratório de Bioengenharia e Biomecânica. Neste sentido, enquanto o foco do AV desenvolvido é centrado na interação e imersão do paciente com o jogo por meio do sensor Kinect, o objetivo deste trabalho é a análise biomecânica dos movimentos executados pelo paciente por meio dos dados gerados pelo Kinect durante a sua interação com o AV. Desta forma, o foco da ferramenta é o feedback fornecido ao profissional responsável pelo acompanhamento da reabilitação. Além disso, uma vez que o Kinect Xbox 360 não foi projetado para análises clínicas, foram executados testes para comparar a sua precisão em relação a um sistema de captura de movimento, o sistema Vicon, tido como padrão ouro, sendo amplamente utilizado em laboratórios de biomecânica para análise cinemática dos movimentos. Neste sentido, foi utilizado testes estatísticos para comparação dos resultados de ambos os sistemas. Em adição, a análise vetorial utilizando o método Statistical Parametric Mapping permitiu fornecer informações acerca de qual coordenada teve maior influência nas diferenças encontradas.
104

BEPS a jeho dopad na daňový systém České republiky / BEPS and its impact on the tax system of the Czech Republic

Chrien, Kristián January 2017 (has links)
The aim of this diploma thesis is to analyze the BEPS measures for the digital economy in connection with the relevant measures related to this sector of the economy. The first part of the thesis characterizes the digital sector and its key business models. The main risks in the field of direct and indirect taxation are described below. The second part of the thesis analyzes the BEPS special measures related to the digital economy sector as well as other measures related to the digital economy. The third part of the thesis describes measures for the digital sector within the framework of the Anti-BEPS initiative, which took place in the European Union. Describes measures under the ATAD Anti-Tax Avoidance Directive in three new areas not addressed by the BEPS project. This section also addresses the measures contained in the DAC Administrative Cooperation Directive and the EU Action Plan for Fair and Efficient Taxation of Corporate Income. The last chapter deals with the analysis of proposed solutions from the point of view of the Czech Republic. It models specific measures within a permanent establishment and withholding tax on the digital economy sector in the Czech Republic, specifically on the field of web hosting. The goal is to quantify the possible impact on tax collection from transactions falling within the web hosting business model.
105

Participation in infrastructuring the future school:a nexus analytic inquiry

Halkola, E. (Eija) 29 November 2015 (has links)
Abstract In information systems (IS) research, there is increasing interest in understanding complex and large-scale efforts. This study examines the complexity involved in infrastructuring within a novel context: the educational network of a Finnish city. A unique aspect is this study’s focus on children’s participation in infrastructuring. It contributes to the existing body of literature by addressing the concepts of discourses in place, interaction order, and historical body, as drawn from nexus analysis. It offers these concepts as theoretical tools for understanding the complexity of infrastructuring, and furthers exploration of user participation in IS research through a careful analysis of actor participation in the infrastructuring venture in question. The findings of this study foreground a multitude of actors, both adults and children, as well as their various activities and the versatility of the involved objects of design. The central social actors include educational officials, schools (teachers, headmasters, and pupils), researchers, and local and global companies. Infrastructuring in this research includes planned activities concerning developed solutions, but also emergent activities for adapting planned solutions to local schools’ everyday practices, revealing the intimate intertwining of practices and technologies. In particular, the past temporal horizon and shared histories of the communities involved are highlighted in terms of the concept of the historical body. The analysis on the historical bodies of the actors foregrounded the local aspects that were appreciated, but also challenged in infrastructuring. The concept of interaction order was found to be useful for analyzing the heterogeneity, multivoicedness, tensions between local and global dimensions, and power aspects inherent in infrastructuring As a practical implication, the nexus analytic concepts of historical body and interaction order are suggested as means of better understanding local settings and the power relationships of various actors, and are also useful for practitioners preparing for infrastructuring. / Tiivistelmä Kiinnostus monimutkaisiin ja laaja-alaisiin hankkeisiin on lisääntynyt tietojenkäsittelytieteiden tutkimuksessa. Tämä tutkimus tarkastelee infrastrukturoitumiseen liittyvää monitahoisuutta uudessa yhteydessä, erään suomalaisen kaupungin kouluverkon kannalta. Uutena näkökulmana tässä tutkimuksessa on lasten osallistuminen infrastrukturoitumiseen. Teoreettisiksi työkaluiksi infrastrukturoitumisen monitahoisuuden ymmärtämiseksi tämä tutkimus tarjoaa neksusanalyyttisiä käsitteitä ’discourses in place’, ’interaction order’ ja ’historical body’. Tässä tutkimuksessa toteutettu analyysi erilaisten toimijoiden osallistumisesta kyseisen hankkeen infrastrukturoitumiseen edistää käyttäjien osallistumiseen liittyvää tietojenkäsittelytieteen tutkimusta. Uusina tuloksina tässä tutkimuksessa ovat toimijoiden - sekä aikuisten että lasten - moninaisuus, heidän erilaiset toimintatapansa sekä suunnittelukohteiden monipuolisuus. Keskeisiä toimijoita hankkeessa olivat opetustoimen virkamiehet, koulut (opettajat, rehtorit sekä oppilaat), tutkijat sekä paikalliset ja kansainväliset yritykset. Infrastrukturoituminen tässä hankkeessa sisälsi sekä suunniteltuja ratkaisuja että uusia soveltavia toimintoja, joilla ratkaisut sovitettiin paikallisiin, koulujen jokapäiväisiin käytänteisiin. Käytänteiden ja teknologioiden väistämätön kietoutuminen toisiinsa tuli siten myös esille tässä tutkimuksessa. Erityisesti mennyt ajallinen ulottuvuus sekä yhteisöjen jaettu historia korostuivat neksusanalyyttisen ‘historical body’ -käsitteen kautta. Toimijoiden aiempien kokemusten tarkastelu tämän käsitteen avulla toi tutkimuksessa esille myös ne paikalliset tekijät, joita infrastrukturoitumisessa arvostettiin, mutta toisaalta myös haastettiin. Neksusanalyyttinen ’interaction order’ -käsite osoittautui hyödylliseksi infrastrukturoitumiseen liittyvän monimuotoisuuden, osallistujien moninaisuuden, paikallisten ja globaalien ulottuvuuksien sekä valtasuhteiden tarkastelemiseksi. Käytännön toimijoille neksusanalyyttisten käsitteiden (’historical body’ ja ’interaction order’) soveltamista suositellaan paikallisten toimintapuitteiden ja eri toimijoiden valtasuhteiden ymmärtämiseen paremmin. Näiden käsitteiden käyttö on hyödyllistä myös käytännön toimijoille järjestettäessä infrastrukturoitumiseen osallistumista.
106

Banking sector depth & long-term economic growth in the GCC States : relationship nature, sector development status & policy implications

Al-Moulani, Ali J. January 2016 (has links)
The thesis investigates the nature of the relationship between the banking sector depth and long-term economic growth in the Gulf Cooperation Council (GCC) States, assesses the banking sector development status in each of the States, and underlines the policy implications in the light of the banking-growth nexus and the banking development benchmarking models’ findings for the region by undertaking three projects. The thesis examines the nature of the relationship between banking sector depth and long-term economic growth in the NRBC—as a proxy for the GCC States— vis-à-vis the rest of the world countries. For the empirical investigation, a dynamic panel data approach, i.e. Generalised Method of Moments (GMM), is adopted over the period 1961 to 2013. By utilising mixed effects and System GMM frameworks, the research identifies the countries with the strongest banking-growth relationships and establishes the banking sector development determinants in those countries. Employing a novel benchmarking process, the thesis assesses the status of the banking sector development in each of the GCC member countries and simulates the change in the banking sector depth across the Gulf region over a period of ten years to highlight the potential policy implications for the sector development. The findings of the thesis suggest that the relationship between banking sector depth and long-term economic growth in the NRBC is non-linear, where the relationship between the banking sector depth and economic growth turns from positive to negative beyond certain levels of sector depth. In comparison to other countries, the results indicate that the banking-growth nexus in the NRBC exhibits a smaller total effect magnitude as well as a shorter time between the change in the sector depth and its effect on economic growth. The benchmarking of the banking sectors in the GCC region suggests that in five of the six member countries the banking sectors are underdeveloped. The simulation results predict that the banking sectors will develop further in half of the countries in the region, given their current levels of banking sector development determinants, while two countries require reforms in terms of undertaking regulations and policies to avoid seeing their sector development levels deteriorate. The thesis contributes to theory by confirming findings in the literature and expanding the body of knowledge through novel findings. This research also contributes to policy by demonstrating the significance of the banking sector development for long-term economic growth in the NRBC, providing policymakers in the Gulf States with the status of their banking sectors, and underlining the banking sector depth determinants that ought to be considered when setting regulations and policies that are aimed at developing the banking sector further.
107

Essays in oil and the economic development of resource rich countries / Essais sur le pétrole et le développement économique

Seghir, Majda 09 December 2014 (has links)
La richesse naturelle est-elle un gage de prospérité ou se révèle-t-elle être une malédiction? Comment le pétrole a-t-il façonné l'évolution économique des pays producteurs ? Dans le prolongement de ces interrogations, l'objectif de cette thèse est de progresser dans la compréhension des mécanismes qui font que le pétrole est, pour les pays exportateurs, aussi souvent une malédiction qu'une bénédiction. Les travaux empiriques qui constituent notre thèse permettent ainsi de répondre à trois questions distinctes : (i) quelle est la contribution du pétrole en tant que ressource énergétique (ou source d'énergie) au processus de croissance économique ? (ii) quels sont les effets directs et indirects de la dépendance aux revenus pétroliers sur la croissance économique et (iii) la malédiction pétrolière n'est-elle pas une question qui renvoie à la stabilité macroéconomique?Notre analyse met ainsi en évidence les résultats suivants : (i) une richesse pétrolière abondante et la surconsommation de pétrole observée dans une large majorité de pays exportateurs de pétrole contribuent positivement au processus de croissance économique. Ce résultat n'est toutefois valable que sur le court terme. En effet, sur le long terme, la consommation de pétrole s'avère être une conséquence de la croissance économique ; (ii) le pétrole en tant que source de revenus impacte la croissance économique directement et indirectement via ses effets sur le montant et la qualité des dépenses publiques ainsi que sur l'ouverture commerciale. Au regard de ces mécanismes de transmission, nos résultats montrent qu'au-delà d'un certain seuil de dépendance aux revenus pétroliers, la croissance économique est entravée par les effets directs et indirects de la rente pétrolière. Toutefois, ces effets peuvent être contenus, tout d'abord, en réduisant la dépendance aux revenus pétroliers, en améliorant, ensuite, la gouvernance et, enfin, en allant vers davantage de stabilité politique ; (iii) les revenus pétroliers, de part leur extrême instabilité peuvent nuire à la croissance économique en induisant des distorsions macroéconomiques. Cette instabilité se traduit plus précisément par une appréciation du taux de change réel, une hausse des dépenses publiques et de l'inflation. Les pays les plus tributaires de la rente pétrolière sont les plus exposés à cette instabilité macroéconomique. De même, les pays où l'efficacité et la crédibilité du gouvernement sont moindres sont ceux où la croissance économique pâtit le plus de cette instabilité macroéconomique.Le pétrole est ainsi un atout pour les économies des pays exportateurs de pétrole dont il faut maitriser les effets indésirables sur l'économie. Une première solution consisterait alors à réduire le niveau de dépendance de l'économie aux revenus pétroliers pour diminuer le risque d'exposition à la volatilité des prix du pétrole et en réduire le risque de contagion à l'économie. Une autre solution nécessiterait d'améliorer la capacité des gouvernements à mettre en place des politiques économiques efficientes. / Is natural wealth a guarantee of prosperity or is it a curse? How has petroleum shaped growth economic process in oil producing countries? To the extent that these questions have to be raise, the purpose of this thesis is to move towards a better understanding of the mechanisms that make oil becoming a curse as often as a blessing, in oil exporting countries. The empirical studies conducted in this thesis help answer three main questions: (i) What is the contribution of oil as energy (or an energy source) in the process of economic growth? (ii) What are the direct and indirect effects of dependence to oil revenues on economic growth? (iii) Is the oil curse a question of macroeconomic stability?Our contributions thus highlight the following results. (i) Abundant oil wealth and overconsumption observed in the vast majority of oil exporting countries contribute positively to the economic growth process. This result is, however, valid only in the short term. Indeed, in the long term, oil consumption appears to be a consequence of economic growth. (ii) Oil as a source of revenue impacts economic growth directly and indirectly through its effect on the amount and quality of public spending as well as on trade openness. Given these mechanisms, our results show that beyond a certain threshold of dependence on oil revenues, economic growth is constrained by the direct and indirect effects of oil revenues. However, these effects can be contained, first, by reducing dependence on oil revenues; then, by improving government effectiveness; and finally by increasing political stability. (iii) Oil revenues, due to their extreme instability may harm economic growth by inducing macroeconomic distortions. This instability results more precisely by an appreciation of the real exchange rate, a rise in public spending and inflation. The most dependent are countries, the most they are exposed to macroeconomic instability. Similarly, countries with an efficient and credible government are the one which suffer economic growth suffers the less from macroeconomic instability.Oil is, thus, a vantage for oil exporting countries but the adverse effects of such a natural resource on the economy must be mastered. One solution would, then, be to reduce the level of dependence of the economy on oil revenues to reduce the exposure to volatile oil prices and to reduce the risk of contagion to the economy. Another solution would be to improve the ability of governments to implement efficient economic policies.
108

Online community as experience and discourse:a nexus analytic view into understandings of togetherness online

Martinviita, A. (Annamari) 03 October 2017 (has links)
Abstract This thesis studies online community as a discursive phenomenon and as an experience. The ethnographic approach employed in this study allows the open exploration of meanings and experiences associated with community by site members, designers and outside commentators in three online environments. Extensive participant observation is supplemented by interviews, surveys and analysis of the interaction surrounding the topic of community. Nexus analysis provides an understanding of social action as the intermingling of historical bodies, interaction orders and discourses embedded in the scene of action. The thesis argues that the concept of community functions as a boundary object, taking different meanings in each context it is employed in. Community can be used to describe strong community experiences or lighter varieties of togetherness online; it can be a pragmatic term simply referring to the user base of a site; or it can incorporate many understandings related to the shared identities and shared practices in the social scene being referred to. The work thus provides a theoretical contribution to ongoing academic discussions related to defining online community, as well as a great deal of empirical knowledge on how experiences of togetherness are created online. Such knowledge may be used to inform future technology development and administrative practices that are sensitive to the many elements affecting social interaction in online spaces. / Tiivistelmä Tämä väitöskirja tarkastelee verkkoyhteisöllisyyttä diskursiivisena ilmiönä sekä kokemuksena. Väitöskirjassa tutkitaan, minkälaisia merkityksiä ja kokemuksia kolmen eri verkkoympäristön jäsenet, kehittäjät ja ulkopuoliset kommentoijat liittävät yhteisöllisyyteen. Tutkimuksen etnografinen lähestymistapa sekä neksusanalyyttinen ote mahdollistavat sen, että sosiaalista toimintaa voidaan analysoida tapahtumapaikkaan eli verkkoympäristöön ja -yhteisöön liittyvien historiataustojen, vuorovaikutusjärjestysten ja diskurssien sulautumana. Tutkimusaineisto koostuu pitkäkestoisesta osallistuvasta havainnoinnista, haastatteluista, kyselytutkimuksista sekä yhteisöllisyyttä käsittelevästä vuorovaikutuksesta tutkituissa verkkoympäristöissä. Väitöstutkimus esittää, että yhteisön käsite toimii rajaobjektina eli se saa eri merkityksiä kussakin kontekstissa, jossa se esiintyy. Ensinnäkin yhteisö-käsitteellä voidaan viitata vahvoihin yhteisöllisyyden kokemuksiin tai keveämpiin yhdessäolon muotoihin. Toiseksi yhteisö-käsite voi toimia käytännöllisenä synonyymina tietyn sivuston käyttäjäkunnalle. Kolmanneksi yhteisö-käsite voi sisältää yhtä aikaa monenlaisia merkityksiä, jotka liittyvät puheenaiheena olevan verkkoympäristön yhteisiin identiteetteihin ja käytänteisiin. Väitöstutkimus tuo uuden teoreettisen näkökulman yhteisö-käsitteen määritelmiä pohtiviin akateemisiin keskusteluihin sekä paljon empiiristä tietoa siitä, miten yhdessäolon kokemukset rakentuvat verkossa. Tätä tietoa erilaisista verkkovuorovaikutusta muokkaavista elementeistä voidaan hyödyntää muun muassa uusien teknologioiden ja ylläpitotoimintojen kehittämisessä.
109

A nexus in crisis: How Brazil’s push for energy security through sugarcane-based ethanol is affecting its water security

Fagundes Hubel, Camila January 2020 (has links)
As reliance on energy and water resources grow, so do the concerns regarding their security, especially in terms of availability. A projected rise in population, accompanied by the relentless pursuit of economic growth and increasing climate change, indicate that greater stress will be placed on these same resources. Biofuels are considered to be a viable alternative to fossil fuels and sugarcane-based ethanol has become an important source for energy security in Brazil, its main producer. At the same time, water scarcity issues have prompted the Brazilian government to compose its first National Plan for Water Security. Research shows that change in land use, a prevalent factor in the production of biofuels, can greatly impact water resources through evapotranspiration, suggesting the possibility of the existence of a link between the two events. This study aimed to investigate this phenomenon by assessing how Brazil’s push for energy security through the production of sugarcane-based ethanol could be affecting its water security. The state of Sao Paulo and the lower Cerrado, including the states of Goias, Minas Gerais and Mato Grosso do Sul, were selected as units of analysis since they comprise the largest production area in the country and are located within the La Plata Basin, where water issues have been experienced in the recent past. Results showed impressive increases over the past four decades in the amount of sugarcane and ethanol produced, as well as in the expansion of land used to cultivate sugarcane in both cases. Furthermore, the results disclosed an increasing trend in precipitation deficit for both regions. The discussion revealed that the direct land use change engendered by the expansion of sugarcane cultivation for ethanol cannot be linked to the decrease in availability of rainwater since it did not negatively impact moisture recycling. Indirect deforestation caused by the displacement of pastureland was, however, determined to have contributed to reduced rates of evapotranspiration, negatively impacting continental moisture recycling, which is imperative for levels of rainfall in the La Plata Basin. The study concludes that the increased production of sugarcane-based ethanol in Sao Paulo and in the lower Cerrado, aimed to ensure energy security for Brazil, is negatively affecting its water security through reduced rates of precipitation associated with indirect land use change. More generally, this conclusion provides insights into the energy-water nexus and a better understanding of critical tradeoffs and potentially irreversible risks that can come with isolated solutions to issues pertaining to larger, complex systems. Finally, it stresses the importance of a nexus approach for sustainable development.
110

Membrane Bioreactor-based Wastewater Treatment Plant Energy Consumption: Environmental Data Science Modeling and Analysis

Cheng, Tuoyuan 10 1900 (has links)
Wastewater Treatment Plants (WWTPs) are sophisticated systems that have to sustain long-term qualified performance, regardless of temporally volatile volumes or compositions of the incoming wastewater. Membrane filtration in the Membrane Bioreactors (MBRs) reduces the WWTPs footprint and produces effluents of proper quality. The energy or electric power consumption of the WWTPs, mainly from aeration equipment and pumping, is directly linked to greenhouse gas emission and economic input. Biological treatment requires oxygen from aeration to perform aerobic decomposition of aquatic pollutants, while pumping consumes energy to overcome friction in the channels, piping systems, and membrane filtration. In this thesis, we researched full-scale WWTPs Influent Conditions (ICs) monitoring and forecasting models to facilitate the energy consumption budgeting and raise early alarms when facing latent abnormal events. Accurate and efficient forecasts of ICs could avoid unexpected system disruption, maintain steady product quality, support efficient downstream processes, improve reliability and save energy. We carried out a numerical study of bioreactor microbial ecology for MBRs microbial communities to identify indicator species and typical working conditions that would assist in reactor status confirmation and support energy consumption budgeting. To quantify membrane fouling and cleaning effects at various scales, we proposed quantitative methods based on Matern covariances to analyze biofouling layer thickness and roughness obtained from Optical Coherence Tomography (OCT) images taken from gravitydriven MBRs under various working conditions. Such methods would support practitioners to design suitable data-driven process operation or replacement cycles and lead to quantified WWTPs monitoring and energy saving. For future research, we would investigate data from other full-scale water or wastewater treatment process with higher sampling frequency and apply kernel machine learning techniques for process global monitoring. The forecasting models would be incorporated into optimization scenarios to support data-driven decision-making. Samples from more MBRs would be considered to gather information of microbial community structures and corresponding oxygen-energy consumption in various working conditions. We would investigate the relationship between pressure drop and spatial roughness measures. Anisotropic Matern covariance related metrics would be adopted to quantify the directional effects under various operation and cleaning working conditions.

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