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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

A estrutura do sistema viável de desenvolvimento sustentável a partir dos objetivos de desenvolvimento sustentável da ONU para os municípios do estado de São Paulo: uma aplicação do viable system model para prefeituras municipais / Design of the municipal viable development system based on the United Nation´s sustainable development goals for the municipalities of the state of São Paulo: an application of the viable system model for municipal administration.

Eustachio, João Henrique Paulino Pires 10 August 2017 (has links)
O desenvolvimento municipal sustentável é um fenômeno complexo. Para que seja possível entender tal fenômeno, é necessário levar em consideração como se comportam as diversas variáveis de dimensões distintas e a interação de uma grande quantidade de atores envolvidos em um processo dinâmico, transformando constantemente o sistema social de uma determinada região. Esta dissertação tem em sua essência, ser um trabalho que está de acordo com o novo paradigma da ciência, descartando explicações simples e prontas sobre o desenvolvimento. Busca agregar toda a complexidade, instabilidade e intersubjetividade que o assunto compreende. Assim, o principal objetivo deste trabalho é desenvolver e diagnosticar o sistema de administração das prefeituras municipais para o desenvolvimento sustentável, tendo como base os objetivos de desenvolvimento sustentável (ODS), utilizando como métodos o Viable System Model (VSM) em prefeituras municipais e a criação de Indicador Sistêmico-Cibernético de Desenvolvimento Sustentável (ISCDS) por meio da análise fatorial (AF) para os municípios do estado de São Paulo. Os objetivos específicos também são desenvolvidos de maneira a contribuir ao objetivo principal. Dentre eles estão: diferenciar os diversos conceitos de desenvolvimento, identificar e delimitar o sistema onde acontece o desenvolvimento local, verificar como os ODS podem ser uma forma de promover o desenvolvimento sistêmico, identificar as principais variáveis secundárias que podem compor o desenvolvimento local e que estejam ligadas a cada um dos objetivos de desenvolvimento sustentável da ONU, desenvolver um indicador capaz de medir o desenvolvimento sistêmico utilizando os ODS e, por fim, identificar as diferenças entre os municípios do estado de São Paulo criando agrupamentos de municípios semelhantes. Para tanto, este é um trabalho sistêmico tanto em sua filosofia quanto estrutura, adotando métodos e técnicas tanto quantitativas como qualitativas para se chegar aos resultados das perguntas de pesquisa. Para que fosse possível obter conhecimento suficiente acerca dos temas tratados e propor uma base metodológica sólida de modo a mostrar os resultados esperados, optou-se por realizar um amplo referencial teórico, envolvendo três itens: desenvolvimento, abordagens sistêmico-cibernéticas e objetivos de desenvolvimento sustentável. Os resultados mostraram que é possível aplicar o VSM no sistema administrativo das prefeituras municipais, sendo uma poderosa ferramenta para administrar o a prefeitura de maneira eficiente e também útil para identificar diversas falhas sistêmicas, conforme são expostas nas considerações finais deste trabalho. Por meio da análise fatorial, tendo como base os ODS, foi possível desenvolver um modelo para se medir o desenvolvimento sustentável sistêmico municipal: o ISCDS para os 645 municípios do estado de São Paulo. A partir da obtenção do ISCDS, foram encontrados sete clusters com características diferentes, indicando a necessidade de tratativas administrativas diferentes que visem o desenvolvimento sustentável para cada agrupamento encontrado. / Sustainable municipal development is a complex phenomenon. To understand this phenomenon, it is necessary to take into account not only the way of huge number variables of different dimensions behave, but also how the large number of actors are involved in a dynamic process, constantly transforming the social system of a given region. This dissertation has in its essence, to be a work that is in accordance with the new paradigm of science, discarding simple and ready explanations about development. It seeks to add all the complexity, instability and intersubjectivity that the subject comprehends. Thus, the main objective of this work is to develop and diagnose the municipal town hall administration system for the sustainable development, based on the sustainable development goals (SDG). The methods used are the Viable System Model (VSM) for the municipal town hall management, and the factor analysis to model the Systemic-Cybernetic Indicator of Sustainable Development (SCISD) for the municipalities of the state of São Paulo. Specific objectives are also developed in order to contribute to the main objective. These include: a) to differentiate the various development concepts, b) to identify the system where local development takes place, b) to check how the SDGs can promote systemic development, c) to identify the main variables that could be used to measure sustainable development, and which of them are connected to each of the UN\'s SDGs and, finally, d) to identify the differences between the municipalities of the state of São Paulo, creating clusters of similar municipalities according to the SCISD developed. To do so, this is a systemic work both in its philosophy and structure. It was adopted methods and techniques both quantitative and qualitative to explore to the results of the research questions. In order to obtain sufficient knowledge about the topics addressed and to propose a solid methodological basis to show the expected results, it was decided to make a broad theoretical reference, involving three items: development, systems thinking and cybernetics approaches and sustainable development goals. The results showed that it is possible to apply the VSM in the administrative system of the city halls, being a powerful tool not only to manage the city in an efficient way, but also useful to identify several systemic failures, as they are exposed in the final considerations of this work. Through the factorial analysis, based on the SDGs, it was also possible to develop a model to measure the level of municipal sustainable development: the SCISD for the 645 municipalities of the state of São Paulo. Also, from the SCISD, seven clusters with different characteristics were found, indicating the need for different administrative approaches according to the different at sustainable development characteristics found in each cluster.
32

A estrutura do sistema viável de desenvolvimento sustentável a partir dos objetivos de desenvolvimento sustentável da ONU para os municípios do estado de São Paulo: uma aplicação do viable system model para prefeituras municipais / Design of the municipal viable development system based on the United Nation´s sustainable development goals for the municipalities of the state of São Paulo: an application of the viable system model for municipal administration.

João Henrique Paulino Pires Eustachio 10 August 2017 (has links)
O desenvolvimento municipal sustentável é um fenômeno complexo. Para que seja possível entender tal fenômeno, é necessário levar em consideração como se comportam as diversas variáveis de dimensões distintas e a interação de uma grande quantidade de atores envolvidos em um processo dinâmico, transformando constantemente o sistema social de uma determinada região. Esta dissertação tem em sua essência, ser um trabalho que está de acordo com o novo paradigma da ciência, descartando explicações simples e prontas sobre o desenvolvimento. Busca agregar toda a complexidade, instabilidade e intersubjetividade que o assunto compreende. Assim, o principal objetivo deste trabalho é desenvolver e diagnosticar o sistema de administração das prefeituras municipais para o desenvolvimento sustentável, tendo como base os objetivos de desenvolvimento sustentável (ODS), utilizando como métodos o Viable System Model (VSM) em prefeituras municipais e a criação de Indicador Sistêmico-Cibernético de Desenvolvimento Sustentável (ISCDS) por meio da análise fatorial (AF) para os municípios do estado de São Paulo. Os objetivos específicos também são desenvolvidos de maneira a contribuir ao objetivo principal. Dentre eles estão: diferenciar os diversos conceitos de desenvolvimento, identificar e delimitar o sistema onde acontece o desenvolvimento local, verificar como os ODS podem ser uma forma de promover o desenvolvimento sistêmico, identificar as principais variáveis secundárias que podem compor o desenvolvimento local e que estejam ligadas a cada um dos objetivos de desenvolvimento sustentável da ONU, desenvolver um indicador capaz de medir o desenvolvimento sistêmico utilizando os ODS e, por fim, identificar as diferenças entre os municípios do estado de São Paulo criando agrupamentos de municípios semelhantes. Para tanto, este é um trabalho sistêmico tanto em sua filosofia quanto estrutura, adotando métodos e técnicas tanto quantitativas como qualitativas para se chegar aos resultados das perguntas de pesquisa. Para que fosse possível obter conhecimento suficiente acerca dos temas tratados e propor uma base metodológica sólida de modo a mostrar os resultados esperados, optou-se por realizar um amplo referencial teórico, envolvendo três itens: desenvolvimento, abordagens sistêmico-cibernéticas e objetivos de desenvolvimento sustentável. Os resultados mostraram que é possível aplicar o VSM no sistema administrativo das prefeituras municipais, sendo uma poderosa ferramenta para administrar o a prefeitura de maneira eficiente e também útil para identificar diversas falhas sistêmicas, conforme são expostas nas considerações finais deste trabalho. Por meio da análise fatorial, tendo como base os ODS, foi possível desenvolver um modelo para se medir o desenvolvimento sustentável sistêmico municipal: o ISCDS para os 645 municípios do estado de São Paulo. A partir da obtenção do ISCDS, foram encontrados sete clusters com características diferentes, indicando a necessidade de tratativas administrativas diferentes que visem o desenvolvimento sustentável para cada agrupamento encontrado. / Sustainable municipal development is a complex phenomenon. To understand this phenomenon, it is necessary to take into account not only the way of huge number variables of different dimensions behave, but also how the large number of actors are involved in a dynamic process, constantly transforming the social system of a given region. This dissertation has in its essence, to be a work that is in accordance with the new paradigm of science, discarding simple and ready explanations about development. It seeks to add all the complexity, instability and intersubjectivity that the subject comprehends. Thus, the main objective of this work is to develop and diagnose the municipal town hall administration system for the sustainable development, based on the sustainable development goals (SDG). The methods used are the Viable System Model (VSM) for the municipal town hall management, and the factor analysis to model the Systemic-Cybernetic Indicator of Sustainable Development (SCISD) for the municipalities of the state of São Paulo. Specific objectives are also developed in order to contribute to the main objective. These include: a) to differentiate the various development concepts, b) to identify the system where local development takes place, b) to check how the SDGs can promote systemic development, c) to identify the main variables that could be used to measure sustainable development, and which of them are connected to each of the UN\'s SDGs and, finally, d) to identify the differences between the municipalities of the state of São Paulo, creating clusters of similar municipalities according to the SCISD developed. To do so, this is a systemic work both in its philosophy and structure. It was adopted methods and techniques both quantitative and qualitative to explore to the results of the research questions. In order to obtain sufficient knowledge about the topics addressed and to propose a solid methodological basis to show the expected results, it was decided to make a broad theoretical reference, involving three items: development, systems thinking and cybernetics approaches and sustainable development goals. The results showed that it is possible to apply the VSM in the administrative system of the city halls, being a powerful tool not only to manage the city in an efficient way, but also useful to identify several systemic failures, as they are exposed in the final considerations of this work. Through the factorial analysis, based on the SDGs, it was also possible to develop a model to measure the level of municipal sustainable development: the SCISD for the 645 municipalities of the state of São Paulo. Also, from the SCISD, seven clusters with different characteristics were found, indicating the need for different administrative approaches according to the different at sustainable development characteristics found in each cluster.
33

Joint Estimation of Impairments in MIMO-OFDM Systems

Jose, Renu January 2014 (has links) (PDF)
The integration of Multiple Input Multiple Output (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM) techniques has become a preferred solution for the high rate wireless technologies due to its high spectral efficiency, robustness to frequency selective fading, increased diversity gain, and enhanced system capacity. The main drawback of OFDM-based systems is their susceptibility to impairments such as Carrier Frequency Offset (CFO), Sampling Frequency Offset (SFO), Symbol Timing Error (STE), Phase Noise (PHN), and fading channel. These impairments, if not properly estimated and compensated, degrade the performance of the OFDM-based systems In this thesis, a system model for MIMO-OFDM that takes into account the effects of all these impairments is formulated. Using this system model, we de-rive Cramer-Rao Lower Bounds (CRLBs) for the joint estimation of deterministic impairments in MIMO-OFDM system, which show the coupling effect among different impairments and the significance of the joint estimation. Also, Bayesian CRLBs for the joint estimation of random impairments in OFDM system are derived. Similarly, we derive Hybrid CRLBs for the joint estimation of random and deterministic impairments in OFDM system, which show the significance of using Bayesian approach in estimation. Further, we investigate different algorithms for the joint estimation of all impairments in OFDM-based system. Maximum Likelihood (ML) algorithms and its low complexity variants, for the joint estimation of CFO, SFO, STE, and channel in MIMO-OFDM system, are proposed. We propose a low complexity ML algorithm which uses Compressed Sensing (CS) based channel estimation method in a sparse fading sce-nario, where the received samples used for estimation are less than that required for a Least Squares (LS) or Maximum a posteriori (MAP) based estimation. Also, we propose MAP algorithms for the joint estimation of the random impairments, PHN and channel, utilizing their statistical knowledge which is known a priori. Joint estimation algorithms for SFO and channel in OFDM system, using Bayesian framework, are also proposed in this thesis. The performance of the estimation methods is studied through simulations and numerical results show that the performance of the proposed algorithms is better than existing algorithms and is closer to the derived CRLBs.
34

Introducing Surface Gravity Waves into Earth System Models

Wu, Lichuan January 2017 (has links)
Surface gravity waves alter the turbulence of the bottom atmosphere and the upper ocean. Accordingly, they can affect momentum flux, heat fluxes, gas exchange and atmospheric mixing. However, in most state-of-the-art Earth System Models (ESMs), surface wave influences are not fully considered or even included. Here, applying surface wave influences into ESMs is investigated from different aspects. Tuning parameterisations for including instantaneous wave influences has difficulties to capture wave influences. Increasing the horizontal resolution of models intensifies storm simulations for both atmosphere-wave coupled (considering the influence of instantaneous wave-induced stress) and stand-alone atmospheric models. However, coupled models are more sensitive to the horizontal resolution than stand-alone atmospheric models. Under high winds, wave states have a big impact on the sea spray generation. Introducing a wave-state-dependent sea spray generation function and Charnock coefficient into a wind stress parameterisation improves the model performance concerning wind speed (intensifies storms). Adding sea spray impact on heat fluxes improves the simulation results of air temperature. Adding sea spray impact both on the wind stress and heat fluxes results in better model performance on wind speed and air temperature while compared to adding only one wave influence. Swell impact on atmospheric turbulence closure schemes should be taken into account through three terms: the atmospheric mixing length scale, the swell-induced momentum flux at the surface, and the profile of swell-induced momentum flux. Introducing the swell impact on the three terms into turbulence closure schemes shows a better performance than introducing only one of the influences. Considering all surface wave impacts on the upper-ocean turbulence (wave breaking, Stokes drift interaction with the Coriolis force, Langmuir circulation, and stirring by non-breaking waves), rather than just one effect, significantly improves model performance. The non-breaking-wave-induced mixing and Langmuir circulation are the most important terms when considering the impact of waves on upper-ocean mixing. Accurate climate simulations from ESMs are very important references for social and biological systems to adapt the climate change. Comparing simulation results with measurements shows that adding surface wave influences improves model performance. Thus, an accurate description of all important wave impact processes should be correctly represented in ESMs, which are important tools to describe climate and weather. Reducing the uncertainties of simulation results from ESMs through introducing surface gravity wave influences is necessary.
35

Mathematical Modeling Of Fluidized Bed Combustors With Radiation Model

Alagoz, Duriye Ece 01 August 2006 (has links) (PDF)
Simultaneous solution of the conservation equations for energy and chemical species in conjunction with radiative transfer equation was carried out by coupling a previously developed and tested system model of fluidized bed combustion (FBC) to an existing radiation model. The predictive accuracy of the coupled code was assessed by applying it to 0.3 MWt METU Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) Test Rig burning lignite in its own ash and comparing its predictions with the measured temperatures and concentrations of gaseous species along the combustor and radiative heat fluxes incident on the refractory-lined freeboard walls on two combustion tests, with and without recycle. The predictions of the coupled code were found to be in good agreement with the measurements. For the investigation of the significance of coupling of the radiation model to the system model, temperature predictions of the coupled code were compared with those obtained by the original system model. It was found that the effect of incorporating a radiation model into the system model on the predictions was not significant because the high temperatures of refractory-lined freeboard walls and high surface to volume ratio of the test rig under consideration cause the incident radiative heat fluxes to be dominated by walls rather than the particle laden gas emissions. However, in industrial boilers, freeboard is surrounded by water-cooled membrane walls and boilers have much lower surface to volume ratio. In order to examine the effects of both on radiation in industrial boilers, an investigation was carried out on 16 MWt Stationary Fluidized Bed Boiler (SFBB) by applying radiation model, in isolation from the system model, to the freeboard of the boiler. It was found that in the boiler, incident radiative heat fluxes were dominated by particle laden gas emissions. In brief, the coupled code proposed in this study proves to be a useful tool in qualitatively and quantitatively simulating the processes taking place in an atmospheric fluidized bed boilers.
36

Konzepte der Beschreibung interaktiver Systeme / Concepts of describing interactive systems

Knöpfel, Andreas January 2004 (has links)
Interaktive System sind dynamische Systeme mit einem zumeist informationellen Kern, die über eine Benutzungsschnittstelle von einem oder mehreren Benutzern bedient werden können. Grundlage für die Benutzung interaktiver Systeme ist das Verständnis von Zweck und Funktionsweise. Allein aus Form und Gestalt der Benutzungsschnittstelle ergibt sich ein solches Verständnis nur in einfachen Fällen. Mit steigender Komplexität ist daher eine verständliche Beschreibung solcher Systeme für deren Entwicklung und Benutzung unverzichtbar. <br><br> Abhängig von ihrem Zweck variieren die Formen vorgefundener Beschreibungen in der Literatur sehr stark. Ausschlaggebend für die Verständlichkeit einer Beschreibung ist jedoch primär die ihr zugrundeliegende Begriffswelt. Zur Beschreibung allgemeiner komplexer diskreter Systeme - aufbauend auf einer getrennten Betrachtung von Aufbau-, Ablauf- und Wertestrukturen - existiert eine bewährte Begriffswelt. Eine Spezialisierung dieser Begriffs- und Vorstellungswelt, die den unterschiedlichen Betrachtungsebenen interaktiver Systeme gerecht wird und die als Grundlage beliebiger Beschreibungsansätze interaktiver Systeme dienen kann, gibt es bisher nicht. <br><br> Ziel dieser Arbeit ist die Bereitstellung einer solchen Begriffswelt zur effizienten Kommunikation der Strukturen interaktiver Systeme. Dadurch soll die Grundlage für eine sinnvolle Ergänzung bestehender Beschreibungs- und Entwicklungsansätze geschaffen werden. Prinzipien der Gestaltung von Benutzungsschnittstellen, Usability- oder Ergonomiebetrachtungen stehen nicht im Mittelpunkt der Arbeit. <br><br> Ausgehend von der informationellen Komponente einer Benutzungsschnittstelle werden drei Modellebenen abgegrenzt, die bei der Betrachtung eines interaktiven Systems zu unterscheiden sind. Jede Modellebene ist durch eine typische Begriffswelt gekennzeichnet, die ihren Ursprung in einer aufbauverwurzelten Vorstellung hat. Der durchgängige Bezug auf eine Systemvorstellung unterscheidet diesen Ansatz von dem bereits bekannten Konzept der Abgrenzung unterschiedlicher Ebenen verschiedenartiger Entwurfsentscheidungen. Die Fundamental Modeling Concepts (FMC) bilden dabei die Grundlage für die Findung und die Darstellung von Systemstrukturen. <br><br> Anhand bestehender Systembeschreibungen wird gezeigt, wie die vorgestellte Begriffswelt zur Modellfindung genutzt werden kann. Dazu wird eine repräsentative Auswahl vorgefundener Systembeschreibungen aus der einschlägigen Literatur daraufhin untersucht, in welchem Umfang durch sie die Vorstellungswelt dynamischer Systeme zum Ausdruck kommt. Defizite in der ursprünglichen Darstellung werden identifiziert. Anhand von Alternativmodellen zu den betrachteten Systemen wird der Nutzen der vorgestellten Begriffswelt und Darstellungsweise demonstriert. / Interactive systems are dynamic systems which provide services to one or more users via a user interface. Many of these systems have an information processing core. To effectively use such a system, a user needs to know about the purpose and functional concepts of the system. Only in case of a rather simple functionality, the required knowledge is likely to be obtained by mere exploration of the user interface. For complex systems, a comprehensive description is essential for effective and efficient operation, but also for system development. Especially in the context of this publication, the focus is on the diagrams that are used for communication in the development process of interactive systems.<br><br> With regard to its purpose these descriptions vary in form and notation. In any case, it is the underlying terminology which is crucial to the understandability. Established concepts and notations for the description of generic information processing systems promote a strict separation of three categories of system structures: Compositional structures, behavioral structures and value-range structures.<br><br> This publication suggests a specialization of this approach for the description of interactive systems. The definition of specific notions and semantic layers is intended to provide a complement to existing description approaches in that field that constitutes a mental framework to enhance the efficiency of communication about interactive systems. In focusing to the description aspect only, design principles, system architectures and development methods are the context but not the subject of this work.<br><br> The separation of three semantic layers provides the foundation to distinguish purpose-related, interaction-related and implementation-related models of interactive systems. Each semantic layer is characterized by a specific terminology. Referring to the idea of equivalent models, the compositional system structure varies from layer to layer and provides the framework to ask for the observable behavior and values. The strict assignment of system aspects to system components distinguishes this approach from a simple layering of design decisions in the development of interactive systems as commonly found in the relevant literature. The Fundamental Modeling Concepts (FMC) provide the foundation for the identification and representation of system structures.<br><br> A selection of system descriptions taken from the relevant literature provides the starting point to demonstrate the application of the suggested concept. Purpose, content and form of each example are analyzed with regard to the implied system structure. Weaknesses in the original representation are identified. Alternative models complement the examples to illustrate the benefit of the new approach.
37

Spatial analysis of sea level rise associated with climate change

Chang, Biao 20 September 2013 (has links)
Sea level rise (SLR) is one of the most damaging impacts associated with climate change. The objective of this study is to develop a comprehensive framework to identify the spatial patterns of sea level in the historical records, project regional mean sea levels in the future, and assess the corresponding impacts on the coastal communities. The first part of the study suggests a spatial pattern recognition methodology to characterize the spatial variations of sea level and to investigate the sea level footprints of climatic signals. A technique based on artificial neural network is proposed to reconstruct average sea levels for the characteristic regions identified. In the second part of the study, a spatial dynamic system model (DSM) is developed to simulate and project the changes in regional sea levels and sea surface temperatures (SST) under different development scenarios of the world. The highest sea levels are predicted under the scenario A1FI, ranging from 71 cm to 86 cm (relative to 1990 global mean sea level); the lowest predicted sea levels are under the scenario B1, ranging from 51 cm to 64 cm (relative to 1990 global mean sea level). Predicted sea levels and SST's of the Indian Ocean are significantly lower than those of the Pacific and the Atlantic Ocean under all six scenarios. The last part of this dissertation assesses the inundation impacts of projected regional SLR on three representative coastal U.S. states through a geographic information system (GIS) analysis. Critical issues in the inundation impact assessment process are identified and discussed.
38

Systémový model pro analýzu rozhodování žadatelů projektu CzechEkoSystem / System model for analysis of applicant decision in project of CzechEkoSystem

Polák, Petr January 2012 (has links)
System Dynamics is a powerful approach to understanding the behaviour of complex systems. This thesis is focused on a simulation model, that goes from principles of System Dynamics and the model will solve the problem of insufficient number of applicants that meet a specific set of project requirements, which are defined by the government agency, CzechInvest. The project, CzechEkoSystem, is mainly focused on efficient development of small and medium sized enterprises based on their pioneering business model. The thesis begins by describing the basic theories of System Dynamics that are introduced and elaborated on, within the particular tools of the simulation model problem statement. Then key terms about the CzechEkoSystem project are introduced. In the conclusion, results and recommendations for increasing the portfolio of pioneering small and medium sized enterprises are presented.
39

Návrh informačního systému / Information System Design

Slováček, Jan January 2018 (has links)
This diploma thesis is about a proposal of an information system for the company Smart Connections s.r.o. The diploma thesis is divided into three parts which are theoretical, analytical and proposal part. The aim of this thesis is to analyse current state of the company's information system and to identify its drawbacks and weaknesses. Based on that a proposal of new information system will be made. The last part will focus on benefits and economic evaluation of the new informative system.
40

Modeling least cost electricity system scenarios for Bangladesh using OSeMOSYS / Scenariomodellering för Bangladesh elsystem med hjälp av OSeMOSYS

Olsson, John Mogren January 2020 (has links)
In order to achieve sustainable development, countries like Bangladesh need to develop their electricity systems to guarantee their citizens access to modern energy services and achieve economic development, while not compromising the global climate. The purpose of this study is to examine what mix of technologies leads to the least costs for the electricity system under different scenario assumptions. This is done by creating a model of the electricity system, using the linear optimization tool OSeMOSYS. The results show a prominence of ultra-supercritical coal power as the lowest cost option for baseload generation in the business as usual and most other scenarios. Unlike in previous studies, solar power is economically competitive in every single scenario, and only limited by the amount of land available for new capacity additions. However, by following a cost minimization strategy, without emissions restrictions or high carbon prices, the CO2 emissions of the Bangladeshi electricity sector will increase significantly through the end of the model period in 2045. / För att Bangladesh ska kunna utvecklas på ett hållbart sätt behöver det tillgodose sina medborgares behov av både moderna energitjänster och ekonomisk utveckling. Båda dessa faktorer är nycklar till fattigdomsbekämpning. Detta kommer kräva en kraftig expansion av det nationella elsystemet, vilket riskerar att öka de nationella koldioxidutsläppen signifikant, i konflikt med klimatmålen i Parisavtalet. Syftet med denna studie är att undersöka vilken elmix som innebär de lägsta totala kostnaderna för Bangladesh mellan 2019-2045, och hur stora koldioxidutsläpp detta leder till. Denna undersökning inkluderar, utöver ett ”business as usual” scenario, också 10 andra scenarier med en rad olika antaganden om teknik- och bränslekostnader, samt begränsningar av koldioxidutsläpp. Detta undersöktes genom att konstruera en modell av elsystemet med hjälp av det linjära optimeringsverktyget OSeMOSYS. De indata som använts i denna modell har baserats på en litteraturgenomgång som i största möjliga mån syftat till att reflektera nationella förhållanden. Trots detta har internationella data används i ett flertal fall, vilket inte kunnat undvikas, särskilt då modellen prognostiserar en framtida utveckling över 25 års tid. Resultatet visar att ny ultra-superkritisk kolkraft med en hög termisk verkningsgrad är den billigaste formen av elproduktion som också kan byggas ut i tillräckligt stor skala för att utgöra en stomme i elsystemet. Andra tekniker som direkta elimporter (främst från Indien) via transmissionskabel, eller ny kärnkraft är också använda i stor utsträckning i de flesta scenarierna. Existerande naturgaskapacitet används igenom hela modellperioden, men nya kraftverk förbigås generellt då modellen istället investerar i kolkraft, detta utom i scenarier med ett högt pris på koldioxidutsläpp eller strikta utsläppsbegränsningar tillsammans med en hög efterfrågan på el. Till skillnad från resultatet i tidigare studier är el från solpaneler på industriell skala ekonomiskt konkurrenskraftigt i samtliga 11 scenarier, till och med när ett lägre kolpris antogs, tillsammans med den högre av två potentiella kostnadsbanor för solpaneler. Dock begränsas solkraftens förutsättningar av faktumet att Bangladesh är så pass tätbefolkat att det har en förhållandevis dålig tillgänglighet av mark för solkraft, vilket leder till en lägre total potential för tekniken, jämfört med många andra länder. Även med det högsta antagandet av 53 GW potentiell solkraft – vilket kräver 1.2 procent av all mark i Bangladesh – står tekniken för mindre än 25 procent av all elproduktion. Detta innebär att om kostnadsminimering tillåts vara den ledande principen bakom utvecklingen av Bangladesh elsystem – vilket i praktiken har varit regeringens prioritet fram tills nu – kommer det ske stora utsläppsökningar från ny kolkraft, fram till åtminstone 2045. Denna nya kolkapacitet överskrider den utsläppsbudget som är förenlig med Parisavtalets mål om högst 2 graders uppvärmning, med konsekvenser som riskerar att drabba klimatsårbara länder som Bangladesh.

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