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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.
21

Avaliação do desempenho ambiental de biodiesel produzido a partir de gordura animal segundo diferentes abordagens para situaçõees de multifuncionalidade. / Assessment of the environmental performance of biodiesel produced from tallow considering different approaches for multifunctionality situations.

Alex Rodrigues Nogueira 20 December 2017 (has links)
O Brasil é um país que se destaca pela pujança da pecuária e como importante ator no mercado de biodiesel. Entretanto, há uma carência de estudos que investiguem o desempenho ambiental do biodiesel produzido a partir de gordura animal segundo uma lógica sistêmica. Trata-se de um tema controverso em função do tratamento dado à gordura pois, embora haja demanda e mercado bem estabelecido, há casos em que esta substância é tratada como um rejeito da produção de carne, desconsiderando-se os impactos ambientais pregressos. Neste contexto, o presente trabalho foi desenvolvido com o objetivo de avaliar a criticidade de diferentes abordagens para as situações de multifuncionalidade da cadeia de produção do biodiesel obtido de gordura animal. Para tanto, fez-se uso da técnica de Avaliação do Ciclo de Vida de produtos segundo o enfoque atribucional com escopo do \"berço-ao-portão\" para se determinar o desempenho do biodiesel produzido nas regiões Sul, Centro-Oeste e Sudeste, e disponibilizado (tanto puro quanto na forma das misturas B15 e B8) para a região metropolitana de São Paulo entre os anos de 2013 e 2015. As situações de multifuncionalidade foram analisadas a partir da aplicação de critérios físicos (proporção mássica e conteúdo energético), de critérios econômicos e do Método Surplus, além da expansão das fronteiras do sistema e substituição de cargas ambientais evitadas. Os resultados foram expressos em termos das categorias de impacto de Mudanças Climáticas, Acidificação terrestre, Eutrofização aquática, Formação fotoquímica de oxidantes, Demanda de Energia Primária. Adicionalmente, foram feitas considerações a respeito do indicador de Energy Return On Investment (EROI) e do balanço de emissões de gases de efeito estufa. Os resultados indicaram que a alocação das cargas ambientais do processo de refino de petróleo - para a produção do diesel fóssil usado em atividades de transporte - mostrou-se irrelevante no contexto do presente estudo. No que diz respeito ao processo de transesterificação, os efeitos das abordagens para as situações de multifuncionalidade foram pouco influentes sobre os resultados. Isto porque a magnitude do impacto da atividade pecuária foi tamanha que a amplitude dos resultados variou cerca de 817 vezes (no caso da categoria de Mudanças Climáticas) ou até 1084 vezes (para a Demanda de Energia Primária). / Brazil is a country that stands out for the internal importance of cattle farming and as an important player in the biodiesel market. However, there is a lack of studies focusing the investigation of the environmental performance of biodiesel produced from animal tallow according to a systemic scope. This is a controversial issue, due to the treatment given to tallow as, although there is consistent market demand, there are cases in which this substance is treated as a waste from meat production activities. In this context, this study was conducted aiming the evaluation of the criticality of different approaches to multifunctional situations of the biodiesel production chain from animal tallow. In order to do so, attributional Life Cycle Assessment technique was used according to a \"cradle-to-gate\" scope in order to determine the environmental performance of biodiesel produced in the South, Midwest and Southeast regions, and commercialized (either purely or in the form of B15 and B8 mixtures) at São Paulo metropolitan region between 2013 and 2015. Multifunctionality situations were analyzed based on the application of physical criteria (mass ratio and energy content), economic criteria and the Surplus Method, as well as based on system boundaries expansion and the substitution of avoided environmental burdens. The results were expressed in terms of the following impact categories: Climate Change, Terrestrial Acidification, Aquatic Eutrophication, Photochemical Oxidants Formation, and Primary Energy Demand. In addition, considerations were made regarding the Energy Return On Investment (EROI) indicator and the greenhouse gases emission balance. The results indicated that the allocation of environmental burdens at petroleum refining process - for the production of fossil diesel used in transport activities - proved to be irrelevant in the context of the present study. Regarding the transesterification process, the effects of the approaches for multifunctionality situations were not very influential on the results. This is because the magnitude of the impact of cattle raising activity was such that the results varied by about 817 times (in the case of the Climate Change impact category) or up to 1084 times (considering the Primary Energy Demand).
22

Multifunctional production systems in Brazil : Opportunities, barriers, and implementation

Jonson, Sofia January 2020 (has links)
As populations grow and the call for renewable energy increases, so does the demand for biomass. However, the sustainability of biomass production has been debated. Concerns involve both negative environmental impacts from agricultural production, as well as the effects of increased bioenergy use on food security. Multifunctional production systems are a potential solution to these issues where environmental benefits are promoted in addition to maintained or enhanced biomass output. This study investigates multifunctional production systems in Brazil, as well as incentives and barriers for implementation within the Brazilian context. A systematic literature review was used to identify previous research on multifunctional production systems in Brazil. The review was then complemented by semi-structured open-ended interviews with local experts. The study found that even though common terminology from the field of multifunctional production systems was not frequently used in the Brazilian context, the systems were both studied and implemented. It was also concluded that economic feasibility is a prerequisite for successful implementation. However, factors like environmental circumstances, farmers perceptions, knowledge, and traditions are also important. Thus, effective adoption requires strategies combining economic incentives, policy incentives as well as educational tools. / <p>2020-06-13</p>
23

Multifunctionality of landscapes - an ecosystem service perspective

Hölting, Lisanne 29 June 2021 (has links)
With increasing population growth, changed consumption patterns and the resulting need for resources, the management and use of cultural landscapes has intensified during the last century. Due to this intensification, cultural landscapes in Europe and other human-dominated regions around the world have transformed from multifunctional landscapes (i.e. providing a diverse set of ecosystem services) to more specialized and uniform landscapes (i.e. providing fewer ecosystem services). Since the widespread loss of ecosystem services can seriously affect human well-being, scientists and intergovernmental organizations have increasingly called for the restoration of multifunctionality at the landscape scale. This again resulted in a growing body of literature on the topic and an uncertainty about what multifunctionality actually is about and how to assess multifunctionality. In this dissertation, the focus is on ecosystem service-based multifunctionality (i.e. the quantification of multifunctionality through ecosystem services). Studies of this field generally examine how different ecosystem services interact, where their overall supply is highest and which factors influence the capacity of a landscape to provide multiple ecosystem services. The consideration of multiple ecosystem services at the landscapes scale specifically enables landscapes and the complex interactions within landscapes to be viewed and studied as socio-ecological systems. The assessment of ecosystem service-based multifunctionality is therefore regarded as an important tool for finding sustainable solutions in landscape management. The overall aim of this dissertation was to enhance and strengthen the concept of multifunctionality from a scientific point of view, and to provide novel conceptual and empirical insights on landscape multifunctionality that are relevant for environmental planning and management. In this dissertation, I have specifically focused on three topics that present challenges for the assessments of ecosystem service-based multifunctionality: 1) overcoming the conceptual and methodological uncertainties related to quantitative multifunctionality assessments, 2) accounting for spatial variability of ecosystem service supplies and 3) differentiating between stakeholders’ perspectives on multifunctionality. Each article of this cumulative dissertation focuses on one of the three challenges: The first article (Chapter 2) presents a quantitative literature review of 101 multifunctionality assessments. Conceptual and methodological differences between ecosystem function- and ecosystem service-based multifunctionality assessments were identified, as well as the most commonly used multifunctionality metrics: threshold approaches, average or sum approaches and diversity indices. The second article (Chapter 3) uses 18 ecosystem service indicators to quantify multifunctionality at the municipality scale (alpha-multifunctionality) and further introduces a new multifunctionality indicator (beta-multifunctionality) that accounts for the unique ecosystem service contributions of municipalities to regional multifunctionality. The results of this article show how multifunctionality at the municipality scale, as well as the unique contributions of municipalities to regional multifunctionality vary across Europe and across different land system archetypes. Finally, the third article (Chapter 4) of this dissertation uses eleven ecosystem service indicators to quantify multifunctionality in two peri-urban landscapes in Europe: the Vereinigte Mulde in Germany and the Kromme Rijn in the Netherlands. By weighting the ecosystem service indicators with stakeholder-derived valuations of the ecosystem services, a differentiation between multifunctionality beneficiaries was achieved. The main contributions of this thesis therefore include an overview of the most recent multifunctionality assessments and the testing of two alternative approaches to assess ecosystem service multifunctionality. By compiling previously used methods and linking them with the most recent conceptual advancements in scope of the literature review, I showed that a clear distinction between studies with an exclusively ecological focus and studies with a more integrated socio-ecological perspective is needed to strengthen the application of the multifunctionality concept. As a follow up on this review, I was able to derive common steps in multifunctionality assessments, as well as recommendations for future studies. In scope of the second and third article, I was able to highlight some specific challenges in current multifunctionality assessments and to test methods that go beyond the common quantification of multifunctionality at single spatial scales or for society as a whole. First of all, my work shows that, due to spatial variability of ecosystem service supplies, the diversity of ecosystem services (alpha-multifunctionality) cannot be maximized in all areas. Accounting for unique ecosystem service supplies (beta-multifunctionality) could thus be more relevant for finding viable land management solutions than assessing ecosystem service hotspots only. This approach is especially applicable, if maximizing (alpha-) multifunctionality is not possible or wanted. Second, maintaining a high diversity of ecosystem services is only meaningful, if the ecosystem services are demanded by society and if no land use conflicts evolve through increased multifunctionality. In my last research paper, I therefore show that accounting for different perspectives of stakeholders on landscape multifunctionality is another crucial aspect for finding viable and sustainable land management solutions. All in all, I conclude that maintaining a high diversity of ecosystem services that relevant to various stakeholders and at spatial scales that allow an implementation of multifunctionality, is important for preventing environmental degradation and for ensuring that society as a whole can benefit from landscape multifunctionality. Quantitative multifunctionality assessments can be used in various ways to answer current research questions in landscape ecology and thus to support the maintenance of ecosystem services in cultural landscapes. However, further development, improvement and applications are needed for multifunctionality assessments to work as strong tools for management and decision-making.
24

Ekosystemtjänster i den fysiska planeringen : En studie av Länsstyrelsen i Östegötland samt Linköpings, Motala och Ödeshögs kommun / Ecosystem services in spatial planning : A study of the County Administrative Board in Östergötland and the municipalities of Linköping, Motala and Ödeshög

Engström, Anna, Thuresson, Angelica January 2021 (has links)
Ekosystemtjänster är de ekologiska funktioner, egenskaper eller processer som bidrar till att främja människors välbefinnande. Mänsklig aktivitet kan ha negativ påverkan på ekosystemtjänster men genom att integrera ekosystem inom flera samhällssektorer och politiska områden kan det strävas efter att dessa genererar viktiga ekosystemtjänster. I denna uppsats undersöks hur ekosystemtjänster integreras i den fysiska planeringen. I undersökningen har en dokumentanalys genomförts tillsammans med att tjänstemän från tre kommuner samt Länsstyrelsen intervjuats. Uppsatsens teoretiska ramverk utgörs av den socio-ekologiska planeringsteorin samt begreppet ekosystemtjänster. Resultatet visar på att arbetet med att integrera ekosystemtjänster i planeringen är olika inarbetat utifrån varje kommuns egna förutsättningar. Att värna om ekosystemtjänster kan skapa mervärden i samhället. Kunskap och samverkan är något som anses vara viktigt för att skapa förståelse inom ämnet och att i framtiden monetärt värdesätta ekosystemtjänster skulle kunna bidra till en ökad förståelse för vad de bidrar med och vad som skulle kunna gå förlorat. / Ecosystem services are the ecological functions, properties or processes that contribute to promoting human well-being. Human activity can have a negative impact on ecosystem services, but by integrating ecosystems into several sectors of society and policy areas, it can be ensured that these generate important ecosystem services. This essay examines how ecosystem services are integrated into spatial planning today. In the survey, a literature study was conducted together with interviews with officials from three municipalities and the County Administrative Board. The theoretical framework of the thesis consists of the socio-ecological planning theory and the concept of ecosystem services. The results show that the work of integrating ecosystem services into the planning is differently incorporated based on each municipality's own conditions. Protecting ecosystem services can create added value in society. Knowledge and collaboration are considered important for creating understanding within the subject and that in the future monetary valuation of ecosystem services could contribute to an increased understanding of what they contribute and what could be lost.
25

Společensko-kulturní centrum s radnicí v Kohoutovicích / Socio-cultural centre with townhall for the district Brno-Kohoutovice

Ľuptáková, Lenka January 2016 (has links)
The building of the town hall Brno Kohoutovice is situated on the site next to the local hospital. Currently, there is a widespread paved area, which has become the place for markets and other cultural activities. Town hall completed urban structure, built on the most visible plot, and closes the plaza on the east side. From the south, the square is open to Kohoutovická valley. It is closed and opened at the same time by a colonnade. Functional composition is expressed in both - size and material. On a solid concrete base, which holds cultural and social events, lie two light steel boxes dedicated to the town hall. The middle part is cantilivered into the square, which symbolizes the proximity of town hall offices to the citizens. It is dedicated to the departements, which are in daily contact with the public. The upper part with large terrace has representative function. There are the internal departements and a ceremonial hall.
26

Achieving Sustainable Urban Drainage through Multifunctionality / Hållbar dagvattenhantering genom multifunktionalitet

Schäfer, Benjamin January 2019 (has links)
No description available.
27

A Valuation Study on Multifunctionality of Agriculture and Multifunctional Agriculture in South Korea: Beyond 6th Industrialization / 韓国における農業の多面的機能と多面機能型農業に関する価値評価研究:6次産業化を超えて

Jung, Hyun Hee 26 September 2022 (has links)
京都大学 / 新制・論文博士 / 博士(農学) / 乙第13507号 / 論農博第2905号 / 新制||農||1095(附属図書館) / 学位論文||R4||N5407(農学部図書室) / (主査)准教授 沈 金虎, 教授 浅見 淳之, 教授 栗山 浩一 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
28

Multifunctionality of the I3 Muscle of Aplysia via Regional Activation by Identified Neurons

McManus, Jeffrey M. 11 June 2014 (has links)
No description available.
29

<b>BISMUTH-BASED LAYERED SUPERCELL MULTIFERROIC THIN FILMS TOWARDS MULTIFUNCTIONALITY AND DEVICE APPLICATIONS</b>

Jianan Shen (11171664) 02 July 2024 (has links)
<p dir="ltr">Multiferroics, which exhibit multiple ferroic orderings within a single material system, have substantial potential for applications in sensors, transducers, memory devices, and energy harvesters. However, the development of single-phase multiferroics that demonstrate roomtemperature properties remains limited by inherent contradictions in d-orbital occupancy between magnetic and ferroelectric materials. This dissertation focuses on addressing this challenge through the exploration of a novel bismuth-based, single-phase multiferroic thin film that features an exotic layered supercell (LSC) structure and displays multiferroic properties at room temperature. The primary aim is to deepen the understanding of LSC materials and advance their applications in practical devices. The dissertation is structured as follows: It begins with an introduction to the fundamental concepts of multiferroics, including their classifications and applications, the specific characteristics and growth mechanism of LSC materials, and other relevant background knowledge. This is followed by a detailed description of the experimental techniques employed. The core of this dissertation comprises four chapters that present a comprehensive study of LSC materials. The first chapter discusses a nanocomposite system combining an LSC material, Bi1.25AlMnO3.25, with Au nanoparticles (NPs), highlighting its tunable microstructure and multifunctional properties influenced by growth temperature. The second chapter explores the integration of Bi2NiMnO6 on a flexible mica substrate, demonstrating the potential of LSC materials for use in flexible electronics, with performance maintained across various bending conditions. The third chapter details the development of freestanding LSC thin films by utilizing a water-soluble sacrificial layer, which are shown to preserve their microstructure and properties after being transferred onto a silicon substrate. Building on this, the fourth chapter investigates the reuse of recycled SrTiO3 substrates for subsequent thin film growth, examining changes in surface strain states and chemistry to guide sustainable practices in complex oxide thin film processing. In summary, this dissertation presents an extensive examination of LSC multiferroics, revealing their significant promise for multifunctional applications and integration into flexible and silicon-based electronics. Additionally, the work explores sustainable methods for substrate reuse, contributing further to the field of material sciences.<br></p>
30

Synthèse des matériaux hybrides organiques inorganiques multifonctionnalisés / Synthesis of multifunctionalized organic inorganic hybrid materials.

Cheikh Ibrahim, Ajfane 12 December 2012 (has links)
L'objet de cette thèse a été l'étude de la structuration et de la fonctionnalisation de matériaux hybrides organiques-inorganiques par le procédé sol-gel.La synthèse et la caractérisation de nouvelles membranes à conduction protonique, pour pile à combustible à membrane échangeuse de protons, ont été réalisées dans la première partie. Des membranes hybrides à base de polyéthylène glycol hautement fonctionnalisées par de l'acide sulfonique ont été synthétisées et caractérisées d'un point de vue physicochimique et conductivité protonique. Elles présentent des bonnes propriétés mécaniques, une stabilité chimique suffisante et une conductivité protonique pertinente pour être utilisées comme électrolyte dans les piles à combustible à membrane échangeuse de proton.Dans une seconde partie, nous avons développé des matériaux hybrides mésoporeux et multifonctionnalisés dans les pores en présence de tensioactif de type copolymère block non-ionique (P123). Deux sondes ont été utilisées pour cette étude: la capacité d'échange protonique et le contrôle de la croissance des nanoparticules d'or dans les pores. / The aim of this work was focused on the structuration and the functionalization of organic-inorganic hybrid materials by the sol-gel process.The synthesis and characterization of new proton conductive membranes for fuel cell proton exchange membrane (PMFC), was prepared in the first part. Hybrid membranes based on polyethylene glycol highly functionalized with sulfonic acid have been synthesized and characterized through a physicochemical and proton conductivity. They have good mechanical properties, a sufficient chemical stability and a performant proton conductivity to be used as an electrolyte in fuel cell proton exchange membrane.In the second part, we have developed hybrid mesoporous materials with porous multifunctionalized in the presence of surfactant nonionic block copolymer (P123). Two probes were used for this study: the proton exchange capacity and the control of the growth of gold nanoparticles in the pores.

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