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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.
91

Niche innovation dynamics and the urban mobility transition

Cannon, Russell January 2019 (has links)
This thesis seeks to provide a detailed understanding of the introduction of dockless bike-sharing to London. As part of a wave of new smart and shared mobility services that are aiming to transform the way people move around cities, this emerging form of transport has created disruptions in London since its launch in 2017. This study aims to analyse to what extent dockless bike-sharing aligns or conflicts with the aims and objectives of local authorities governing public space in London. In doing so, it also aims to reveal insights into transformations in contemporary mobility by exploring the dynamics of niche innovations within socio-technical transitions, thus contributing to knowledge in the field of transition studies.To do this, a qualitative case study methodology was employed using document analysis and interviews with four stakeholders integrally involved in the case study, representing both public authorities and a private sector dockless bike-sharing operator, Mobike.The findings demonstrate that dockless bike-sharing is well aligned with the city’s explicit objectives to reduce car dependency and encourage active travel. It has particular potential to make cycling more accessible by bringing bike-sharing to parts of the city that do not have access to the pre-existing, docked bike-sharing scheme, operated by the central transport authority, Transport for London. Despite this, dockless bike-sharing, as a niche innovation, has struggled to break into the existing urban mobility regime. This can be seen to result from a variety of factors that include a failure to collaborate and build local legitimacy or pay sufficient regard to local conditions during early implementation. Furthermore, dockless bike-sharing’s demand for flexible parking has resulted in uses and misuses of public space that have created friction and placed the innovation in conflict with the existing physical urban landscape and the authorities that govern it. Its momentum has been further hindered by London’s complex governance structure, a structure which has not proved conducive to the dockless bike-sharing operating model. It is posited that if dockless bike-sharing is to build momentum and achieve its potential to expand the reach of bike-sharing in London, greater support is required from public authorities.
92

Simulation and Statistical Inference of Stochastic Reaction Networks with Applications to Epidemic Models

Moraes, Alvaro 01 1900 (has links)
Epidemics have shaped, sometimes more than wars and natural disasters, demo- graphic aspects of human populations around the world, their health habits and their economies. Ebola and the Middle East Respiratory Syndrome (MERS) are clear and current examples of potential hazards at planetary scale. During the spread of an epidemic disease, there are phenomena, like the sudden extinction of the epidemic, that can not be captured by deterministic models. As a consequence, stochastic models have been proposed during the last decades. A typical forward problem in the stochastic setting could be the approximation of the expected number of infected individuals found in one month from now. On the other hand, a typical inverse problem could be, given a discretely observed set of epidemiological data, infer the transmission rate of the epidemic or its basic reproduction number. Markovian epidemic models are stochastic models belonging to a wide class of pure jump processes known as Stochastic Reaction Networks (SRNs), that are intended to describe the time evolution of interacting particle systems where one particle interacts with the others through a finite set of reaction channels. SRNs have been mainly developed to model biochemical reactions but they also have applications in neural networks, virus kinetics, and dynamics of social networks, among others. 4 This PhD thesis is focused on novel fast simulation algorithms and statistical inference methods for SRNs. Our novel Multi-level Monte Carlo (MLMC) hybrid simulation algorithms provide accurate estimates of expected values of a given observable of SRNs at a prescribed final time. They are designed to control the global approximation error up to a user-selected accuracy and up to a certain confidence level, and with near optimal computational work. We also present novel dual-weighted residual expansions for fast estimation of weak and strong errors arising from the MLMC methodology. Regarding the statistical inference aspect, we first mention an innovative multi- scale approach, where we introduce a deterministic systematic way of using up-scaled likelihoods for parameter estimation while the statistical fittings are done in the base model through the use of the Master Equation. In a di↵erent approach, we derive a new forward-reverse representation for simulating stochastic bridges between con- secutive observations. This allows us to use the well-known EM Algorithm to infer the reaction rates. The forward-reverse methodology is boosted by an initial phase where, using multi-scale approximation techniques, we provide initial values for the EM Algorithm.
93

Energy Transition in Taiwan: A Multi-level Perspective / 台湾におけるエネルギー転換-重層的視座からの分析-

Chen, Yi-Chun 25 November 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(地球環境学) / 甲第22137号 / 地環博第193号 / 新制||地環||38(附属図書館) / 京都大学大学院地球環境学舎地球環境学専攻 / (主査)准教授 森 晶寿, 教授 諸富 徹, 教授 宇佐美 誠 / 学位規則第4条第1項該当 / Doctor of Global Environmental Studies / Kyoto University / DFAM
94

Local NGOs and Adaptation Governance: A Multi-Level Governance Analysis of Adaptation Priorities and NGO Agency in The Gambia

Bah, Tayib M. 10 September 2021 (has links)
No description available.
95

The Swedish socio-technical agro-food system and how it may transition to a more sustainable state through an increased cultivation of grain-legumes

Klingspor, Charlotte, Philipson, Linda January 2021 (has links)
Due to unsustainable production and consumption patterns that cause climate changes, current socio-technical systems, such as the agro-food system, must rapidly undergo sustainability transitions. To transition socio-technical systems is however complex and it usually takes decades, and it is therefore crucial to study how socio-technical systems can transition faster.  Aim – This study aims to investigate under what circumstances a sustainability transition through an increased cultivation of grain-legumes in Sweden can take place and be accelerated. In order to guide the study and thus fulfil the purpose, two research questions have been formulated: 1)  “What are the current main factors that hinder a sustainability transition in terms of an increased cultivation of grain-legumes in the current agricultural value chain of crop production in Sweden?” 2)  “What prerequisites are required to accelerate sustainability transitions in the agricultural value chain of crop production in terms of an increased cultivation of grain-legumes in Sweden?” Method – The methodology used is a qualitative case study of the Swedish agricultural value chain of crop production. The data was collected through interviews, literature review and webinars. The data collected through interviewing was analyzed by using a thematic analysis.  Findings – One main hindering factor refer to the absence of certain value chain processes, both when it comes to actors that can provide Swedish plant-based food producers with extracted proteins from grain-legumes and when it comes to actors that can receive, sort, peel and pack grain-legumes for human consumption at an industrial level. Other main hindering factors regards the lack of financial incentives at several levels as well as a structured and stabilized agricultural socio-technical regime characterized by path dependencies and lock-ins. The found prerequisites required in order to accelerate sustainability transitions include for instance having certain value chain processes to come into place, steer large investments and educated people in the right direction to drive innovation and development as well as an increased sustainability transitioning pressure from the civil society in Sweden.   Implications – The findings of this thesis can increase the knowledge of actors engaged in the agricultural value chain of crop production, but also provide valuable insights for the whole Swedish agro-food sector. This study also provides insights regarding how a sustainability transition can be accelerated based on the findings from the studied case. Another implication is that a larger focus, when researching sustainability transitions, should be put on the role of civil society to understand and facilitate faster sustainability transitions in socio-technical systems. Limitations – The political perspective is not considered, the internal strategies of actors have not been investigated and the focus has only been at the environmental dimension of sustainability, not on the social or economic dimensions.
96

Implementation of the 2030 Agenda in Sweden : Interpretation and application of disability inclusive goals at the local level / Implementering av Agenda 2030 i Sverige : Tolkning och tillämpning av mål för personer med funktionsnedsättning på den lokala nivån

Öman, Béatrice January 2021 (has links)
This thesis studies the transfer of disability targets in the 2030 Agenda for Sustainable Development to the local level in Sweden and how this implementation contributes to the Agenda’s result on a global scale. In the summary of its final official report to the Swedish Government (SOU 2019:13), the Swedish Delegation for the 2030 Agenda states that the expression ‘sustainable development’ is applied in Sweden in two ways: while it is used witha focus on its environmental dimension, there is another, broader definition that also encompasses its social and economic dimensions. In its own terms, the Delegation consistently adheres to the broader definition, in accordance with the meaning of the 2030 Agenda (SOU 2019:13, p. 27). Rather than concentrating on the more amply researched and documented environmental dimension, this thesis highlights a social and economic dimension of the Agenda’s local implementation, bearing in mind the Agenda’s pledge that no one willbe left behind. It examines how those among the 169 targets dealing with the interests of people with disabilities are transposed down to the local level and implemented. The conclusion points at the fact that, although all goals seem understood as indivisible at each level, results may uncover a big difference in how they are implemented and/or measured inpractice, at each of the political-administrative levels involved, which makes it difficult to produce data on quantifiable progress on a specific target.
97

Multi-level security in multiagent systems

Wagner, Gerd 19 October 2018 (has links)
Whenever agents deal with confidential information, it is important that they comply with a principled security policy. We show how the database concept of multi-level security can be applied to inter-agent communication. This includes the case where an unauthorized agent is misinformed on purpose in order to protect confidential information.
98

Extending the Principal Stratification Method To Multi-Level Randomized Trials

Guo, Jing 12 April 2010 (has links)
The Principal Stratification method estimates a causal intervention effect by taking account of subjects' differences in participation, adherence or compliance. The current Principal Stratification method has been mostly used in randomized intervention trials with randomization at a single (individual) level with subjects who were randomly assigned to either intervention or control condition. However, randomized intervention trials have been conducted at group level instead of individual level in many scientific fields. This is so called "two-level randomization", where randomization is conducted at a group (second) level, above an individual level but outcome is often observed at individual level within each group. The incorrect inferences may result from the causal modeling if one only considers the compliance from individual level, but ignores it or be determine it from group level for a two-level randomized trial. The Principal Stratification method thus needs to be further developed to address this issue. To extend application of the Principal Stratification method, this research developed a new methodology for causal inferences in two-level intervention trials which principal stratification can be formed by both group level and individual level compliance. Built on the original Principal Stratification method, the new method incorporates a range of alternative methods to assess causal effects on a population when data on exposure at the group level are incomplete or limited, and are data at individual level. We use the Gatekeeper Training Trial, as a motivating example as well as for illustration. This study is focused on how to examine the intervention causal effect for schools that varied by level of adoption of the intervention program (Early-adopter vs. Later-adopter). In our case, the traditional Exclusion Restriction Assumption for Principal Stratification method is no longer hold. The results show that the intervention had a stronger impact on Later-Adopter group than Early-Adopter group for all participated schools. These impacts were larger for later trained schools than earlier trained schools. The study also shows that the intervention has a different impact on middle and high schools.
99

Risk- och sårbarhetsanalyser - Samverkan när den är som bäst : En kvalitativ studie om samverkan i Blekinge län / Risk and vulnerability analysis - Collaboration at its best : A qualitative study on collaboration in Blekinge County

Ahlgren, Jennifer, Hägerlund, Mikael January 2022 (has links)
Med en ökad utmaning i samhället med att hantera risker och dess konsekvenser sätts en allt större press på samhällets förmåga att agera vid oönskade händelser. Studien omfattar Blekinge län och har som syfte att analysera hur flernivåstyrning påverkar arbetet med risk och sårbarhet. Syftet besvaras av två frågeställningar som behandlar samverkan och utmaningar mellan administrativa nivåer. Studien baseras på en abduktiv ansats där teorin väljs utifrån empirin. Teorin i studiens sammanhang är flernivåstyrning vars ändamål är att analysera studiens tidigare forskning och resultat. Studiens resultat utgörs av en dokumentanalys av risk- och sårbarhetsanalyser (RSA) samt en intervjustudie med tjänstemän som visar på att samverkan mellan administrativa nivåer fungerar. Däremot finns det utmaningar med ansvarsfördelningen som är en konsekvens av en bristande kommunikation i ett hierarkiskt beroende system. Utmaningarna påverkar hur arbetet aggregeras upp i de administrativa nivåerna. / With an increased challenge in society in managing risks and their consequences, an increasing pressure is put on society's ability to act in the event of undesirable events. The study covers Blekinge County and aims to analyze how multilevel governance affects risk and vulnerability. The purpose is answered by two questions that explore collaboration and challenges between administrative levels. The study is based on an abductive approach where the theory is chosen based on empirical data. Results from the study are created by a document analysis of risk- and vulnerability documents (RVA) as well as an interview study from municipal employees. The result shows that collaboration between administrative levels works. However, there are challenges with the division of responsibilities from a lack of communication in a hierarchically dependent system. The challenges affect how the analysis is aggregated up to the administrative levels.
100

En ekonomisk och marknadsmässig utvärdering av vätgasdrivna bränslecellsfordon : Fallstudier inom den svenska transportsektorn / An assessment of the market potential for hydrogen fuel cell vehicles : Case studies within the Swedish transportation sector

Gabrielsson, Gunilla, Hajiakbar, Azadeh January 2016 (has links)
Klimatförändringar och effekterna av global uppvärmning är ett växande problem i världen och anses vara en av vår tids största utmaningar. Idag står Sveriges inrikes transporter av en tredjedel av landets totala växthusgasutsläpp och är i hög grad beroende av fossila drivmedel. För att eftersträva ett hållbart energisystem har politikerna satt upp ett mål om en fossilfri fordonsflotta år 2030. För att uppnå detta mål behöver koldioxidintensiva energikällor gradvis ersättas med renare alternativ. Där har bland andra elfordon och bränslecellsfordon potential att vara nycklar i en sådan teknisk omvandling. Dock finns det många barriärer för att implementera vätgas som drivmedel, däribland de finansiella riskerna kring den stora investeringen i samband med upprättandet av produktion och infrastruktur. Syftet med rapporten har varit att studera om, och på vilket sätt, vätgasdrivna bränslecellsfordon kan bidra till en teknisk omvandling av den svenska transportsektorn. Den ekonomiska ägandekostnaden för fyra utvalda fordonsapplikationer; gaffeltruckar, bussar, distributionsfordon och båtar har studerats för att undersöka vilka som har störst potential att bidra till de vätgasdrivna bränslecellsfordonens genomslag ur ett marknadsmässigt och ekonomiskt perspektiv. Varje fordonsapplikation har jämförts med sina respektive konventionella och/eller miljöanpassade motsvarigheter genom beräkningsmodellen Total Cost of Ownership. Vidare har applicerandet av ett systemperspektiv, med de teoretiska ramverken Multi-Level Perspective (MLP) och Strategic Niche Management (SNM) i fokus, varit värdefullt för förståelsen av vätgasens och bränslecellsfordonens roll i kontexten av ett sociotekniskt system och för att identifiera hur marknadsintroduktionen och diffusionen av dessa ska ske på ett hållbart sätt. Resultaten i denna studie visar på att initiala satsningar på småskaliga projekt inom vätgasdrivna fordonsapplikationer så som gaffeltruckar, bussar, distributionsfordon och båtar har potential att fungera som en katalysator för en framtida introduktion av vätgasdrivna bränslecellsfordon. Sådana projekt skulle inte omedelbart leda till en avsevärd reduktion av koldioxidutsläpp utan snarare hjälpa att bryta barriärerna och underlätta för en framtida marknadsintroduktion av vätgasdrivna bränslecellsfordon i Sverige. Ur ett större perspektiv skulle utvecklingen av vätgasdrivna bränslecellsfordon även uppmuntra till en spridning av andra miljöanpassade alternativ, vilket ytterligare driver fram den tekniska omvandlingen genom positiva feedback-loopar. Då en teknisk omvandling av den svenska transportsektorn kräver en kombination av flera drivmedel och tekniker bör vätgasdrivna bränslecellsfordon betraktas som ett komplement till andra miljöanpassade alternativ, inte en konkurrent. Vidare tyder resultaten på att vätgasdrivna bränslecellstruckar (gaffeltruckar) och bränslecellsbussar kan bli de första applikationerna som introduceras i Sverige via småskaliga implementationsprojekt fram till år 2030 och därefter kommersialiseras. Dessa applikationer har de ekonomiska förutsättningarna som krävs och det finns i dagsläget tydliga drivkrafter och aktörer som verkar för deras utveckling i Sverige. Distributionsfordon med vätgasdrivna räckviddsförlängare finns i Europa och kan, givet att Bonus-malus systemet introduceras, bli ekonomiskt försvarbara i Sverige. Inom båt-applikationen anses pendelfärjor vara lämpliga för enstaka projekt som kan gynna diffusionen av vätgasdrivna bränslecellsfordon, medan deras verkliga genomslag tros bortom 2030. Däremot kan dynamiska effekter i det sociotekniska systemet påskynda utvecklingen applikationerna emellan. Vidare har styrmedel och samordning av infrastruktur och andra strategiska samarbeten identifieras som de viktigaste lösningarna för att få igenom småskaliga implementationsprojekt på kort sikt, och större strukturella förändringar i det svenska transportsystemet på lång sikt. Det bör belysas att nya alternativ så som vätgas och bränslecellsfordon ofta genomgår en långsam marknadsutveckling. Det är därför väsentligt att skapa rimliga förväntningar då det krävs stora förändringar inom infrastrukturen och transportmönster samt betydande teknikutveckling för att dessa ska nå marknadsmässig mognad.

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