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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.
211

Simulação de cenários para o setor sucroenergético brasileiro a partir do método de mapeamento e quantificação de sistemas agroindustriais / Scenario Simulations for the Brazilian Sugarcane Industry from the Method for Mapping and Quantitation Agribusiness Systems

Bryan Manuel Julca Briceño 12 May 2011 (has links)
Os sistemas agroindustriais são estruturas complexas que são influenciadas pelas transformações econômicas, políticas e tecnológicas da sociedade. Assim, as organizações públicas e privadas que estão inseridas nesses sistemas precisam de informações setoriais que as permitam identificar cenários futuros e ajustar seus recursos internos às novas situações geradas pelo ambiente externo. Uma das alternativas para dispor dessa informação é a aplicação de ferramentas de projeção por meio da simulação de cenários. Este trabalho, nesse sentido, tem como foco principal a simulação de cenários para o setor sucroenergético brasileiro a partir do método de mapeamento e quantificação de sistemas agroindustriais. Para atingi- lo, foi aplicada uma pesquisa exploratória e qualitativa, cuja execução foi divida em três fases. A primeira considerou o desenho do sistema agroindustrial da cana-de-açúcar no Brasil, identificando os seus principais setores e variáveis participantes; a segunda compreendeu a quantificação do sistema, estimando, a partir de relações entre as variáveis, os fluxos comerciais dos elos de insumos agrícolas, produção de matéria-prima, insumos industriais e processamento industrial, no ano fiscal de 2008; e, finalmente, na terceira fase foi feita uma simulação de cenários para o período 2011-2015 com base em projeções de mercado e uso de ferramenta eletrônica. A coleta de dados foi realizada por meio de dados primários e secundários, levantados em entrevistas com executivos, pesquisadores, instituições governamentais e organizações setoriais dos diferentes elos do sistema agroindustrial, além de publicações como anuários estatísticos, relatórios, prognósticos, entre outros, elaborados por instituições governamentais e não governamentais. Já o processamento e simulação de cenários foram feitos com a utilização de um software de planilha eletrônica. Como resultados desta pesquisa, portanto, foram apresentadas as etapas necessárias para desenhar, quantificar e simular cenários para o setor sucroenergético, assim como os valores obtidos nos cálculos, que permitirá, em pesquisas futuras, explorar o aperfeiçoamento do modelo de simulação por meio da inserção de novas variáveis e da atualização dos valores atribuídos a elas. / Agroindustrial systems are complex structures that are subject to economic, political and technological changes within society. Therefore, the organization held within these systems must frequently adjust their specific resources to the situations created by the environment. One of the alternatives to identify opportunities and threats to the systems is the application of tools for exploring the future through scenario analysis. Thus, this research focuses on simulating scenarios for the Brazilian Sugarcane Agroindustrial System through the application of the Method for Mapping and Quantifying Agroindustrial Systems. In order to achieve this objective, an exploratory and qualitative research has been made in three phases. The first phase has considered the structure of the Sugarcane Agroindustrial System in Bra zil, identifying their key sectors and variables; the second one has addressed the quantification of the system, estimating the trade flows between farm input suppliers, sugarcane producers, industrial input supplier and sugarcane mills in 2008; and finally, in the third phase a scenario simulation has been done for the period of 2011-2015 based on market projections with the use of an electronic tool. Both primary and secondary data have been used. Primary data have been collected thought interviews with executives, researchers, governmental institutions and industrial organizations representatives, while secondary data have been gathered from publications such as statistical reports and prognostics from private and governmental institutions. The data processing and the scenario simulations have been done by using an electronic spreadsheet software. The results of the research show the necessary stages for drawing the systems structure, quantifying the trade flows between its links and simulating scenarios for the Sugarcane Agroindustrial System. They also show the values obtained from the calculations, which allows the further improvement of the simulation model in future research by updating the values given to the variables as well as by inserting new var iables.
212

Laubholz mit niedriger Umtriebszeit in Nordwestdeutschland - Charakterisierung der Vorkommen, Wachstumsmodellierung und waldbauliche Steuerung / Short-lived Deciduous Tree Species in Northwest Germany - Supply, Growth Modelling and Silvicultural Treatment

Fischer, Christoph 27 October 2017 (has links)
No description available.
213

Analys av användargränssnitt / Analyse of the user interface

Gustavsson, Daniel, Lundström, Julia January 2006 (has links)
Vem avgör vad som är bra användbarhet? Och hur lyckas man bibehålla det genom ett helt program? Dessa frågor och många fler ställdes när arbetet med utformningen av den nya designen startades. Meningen var att ta reda på vad som gäller idag och vad som är intressant för framtiden i frågan om användbarhet. Genom en grundlig analys av designen i programmet SEBS (System Economy Business System) tillsammans med ett flertal andra liknande program har flera problemområden identifierats och motiverats med hjälp av teorier från författare och ISO standarder (International Organisation for Standardization). Uppgiften har en ganska abstrakt natur och ger inte självmant upphov till gedigna praktikfall som lätt presenteras. Trots det blev ett nytt gränssnitt och nya riktlinjer framtagna och arbetssättet och tankarna bakom finns väl dokumenterade. Resultatet måste analyseras av någon som förstår större delen av innebörden i den teoretiska bakgrunden som är presenterad. Resultaten som arbetet skapade gav en djup insikt i svårigheten att framställa programvara som är tilltalande och effektiv. Det är en utmaning många skulle backa för att ta om de visste vad den innebar. Arbetet det innebär kämpar precis som alla projekt där flera människor deltar med att få alla att dra åt samma håll. Det finns inget konkret att satsa på utan alla måste lyssna och försöka samlas kring en vision som symboliserar det kommande resultatet. Hjälpmedel för detta presenteras i rapporten, för det finns fler poänger med att låta verktygen få finnas till hands för mer än bara sammanhållningen. De kan även väcka nya sätt att prata om slutanvändare och hur man ska förhålla sig till dem. / Who decides whether a design is user friendly or not? And what is the trick to maintain that type of design throughout the whole program? These and many more questions were asked when the work with the report were about to begin. The plan is to find out what is relevant for design today and what will be interesting to know about in a present future. Through a fundamentally analysis of the design in the program SEBS (System Economy Business System) together with a number of similar programs, several problem areas has been discovered and motivated by references to different authors and ISO standards(International Organisation for Standardization). Since this task has an abstract nature it does not provide the authors with good case studies that easily can be presented and discussed. Despite that, a new user design has been created and new guidelines for future design have been drawn. The work gained a deep understanding for the difficulties that comes with software manufacturing and a belief that most people would back of if they knew what was waiting down the line in this type of work. As always when project includes several people problems with communications and the ability to struggle at the same direction occurs. Tools to lighten this work are presented and they are not just effective to keep the group together. They can also help to find new ways to talk about the actual user of the developing program.
214

InfoMart Reporting : The process of developing a data discovery tool for Genesys InfoMart

Vestling, Olof January 2015 (has links)
Customer relationship management (CRM) is gaining momentum around the world and a majority of the organizations view customer experience provided by contact-centers as a competitive differentiator. Thus is the importance of understanding these systems very big. The purpose of the thesis is to create a cohesive solution, a prototype, to gather, aggregate and present viable business reports for a number of channels in such a system. The CRM-platform handled in this thesis is called Genesys InfoMart, which is developed by Genesys Telecommunications. The thesis defines the use-cases and reports to be compiled. It does also give a description of how data is cross- correlated across the database and how it was gathered. By involving domain-experts and using a scenario based- approach, requirements have been derived and reports have been developed. It is concluded that the conceptual scenarios were feasible. There are no limitations within the InfoMart data mart with respect to the functionality that the domain-experts demand. A cooperative-evaluation session showed that the conceptual design was approved and that it provided the functionality that the evaluation group requested. Thus concluded that the methodological approach was overall successful and that the requirements were met. It is however recommended to continue the development process by exposing the prototype to end-users evaluation. This can provide insights and information that can be very useful when developing the final product.
215

Staying ahead of the game : a framework for effective aquaculture decision-making

King, Andrew Stephen January 2016 (has links)
Globally, Atlantic salmon aquaculture is faced with a critical challenge: How best to deliver long-term sustainable growth, whilst optimising the opportunity for the expansion of the industry presented by an increasing global seafood demand? The thesis presents a novel framework of complementary decision support approaches to enable decision-makers to better understand the factors influencing aquaculture development, and examine alternative production (growout) technologies that more effectively address the challenges associated with intensification and expansion. The framework was developed through a combination of fieldwork (international data-gathering), key stakeholder discussions, and the application of targeted qualitative and quantitative analytical approaches; using the Tasmanian industry as a Case Study. The initial research focused on shorter-term (tactical) decision support. A situational analysis defined the business environment, and appraised viable expansion options (offshore, closed-containment and extractive bio-remediation). An economic analysis of selected options then provided a comparison of financial performance and risk. The outputs of this initial component next informed strategic decision-making approaches; employing scenario analysis to explore plausible strategies for the adoption of land-based recirculating aquaculture systems; and qualitative modelling to understand the causal dynamics driving and regulating the industry, and their impact on technology selection. Whilst it was clear that business economic viability is paramount, the results suggested that societal acceptance (the Social License to operate) is playing an increasingly important role in influencing business decisions. There is no single ‘right' technological solution; social acceptance, in particular considerations regarding human wellbeing, trust, and animal welfare concerns, will shape the business environment and therefore technology selection. The research emphasised the importance of employing a balance of tactical and strategic decision-making techniques, and of engaging with a broad range of industry stakeholders. It also highlighted the complexity and dynamic nature of the industry and that key variances (economic, regional, strategic, technological, and temporal) must be included in decision-making.
216

Conservation of Ecosystem Services and Biodiversity in Vermont, USA

Watson, Keri B. 01 January 2018 (has links)
Supporting a growing human population while avoiding biodiversity loss is a central challenge towards a sustainable future. Ecosystem services are benefits that people derive from nature. People have drastically altered the earth’s land surface in the pursuit of those ecosystem services that have been ascribed market value, while at the same time eroding biodiversity and non-market ecosystem services. The science required to inform a more balanced vision for land-cover change in the future is rapidly developing, but critical questions remain unanswered regarding how to quantify ecosystem services and ascribe value to them, and how to coordinate efforts to safeguard multiple ecosystem services and biodiversity together. This dissertation addresses several of these challenges using Vermont as a model landscape. Specifically, we begin by estimating the economic value of flood mitigation ecosystem services and show that the externalized value of ecosystem services can be quite high. Second, we assess the role of demand from human beneficiaries in shifting the spatial distribution of ecosystem services, and address the biodiversity and human wellbeing implications of that shift. Third we analyze the tradeoffs and synergies inherent in pursing multiple ecosystem services and biodiversity through conservation, and show that overall ecosystem service conservation is more likely to boost biodiversity outcomes than to undermine them. Finally, I implement statewide scenarios of land-cover change and flood risk in order to assess our ability to quantify ecosystem service outcomes and identify spatial priorities for the future despite land-cover change dynamics that are complex and unpredictable.
217

Models and Computational Strategies for Multistage Stochastic Programming under Endogenous and Exogenous Uncertainties

Apap, Robert M. 01 July 2017 (has links)
This dissertation addresses the modeling and solution of mixed-integer linear multistage stochastic programming problems involving both endogenous and exogenous uncertain parameters. We propose a composite scenario tree that captures both types of uncertainty, and we exploit its unique structure to derive new theoretical properties that can drastically reduce the number of non-anticipativity constraints (NACs). Since the reduced model is often still intractable, we discuss two special solution approaches. The first is a sequential scenario decomposition heuristic in which we sequentially solve endogenous MILP subproblems to determine the binary investment decisions, fix these decisions to satisfy the first-period and exogenous NACs, and then solve the resulting model to obtain a feasible solution. The second approach is Lagrangean decomposition. We present numerical results for a process network planning problem and an oilfield development planning problem. The results clearly demonstrate the efficiency of the special solution methods over solving the reduced model directly. To further generalize this work, we also propose a graph-theory algorithm for non-anticipativity constraint reduction in problems with arbitrary scenario sets. Finally, in a break from the rest of the thesis, we present the basics of stochastic programming for non-expert users.
218

Modelling container logistics processes in container terminals : a case study in Alexandria

ElMesmary, Hebatallah Mohammed January 2015 (has links)
This study aims to optimize the logistics processes of container terminals. Potentially powerful pipe-flow models of container terminal logistics processes have been neglected to date and modelling of terminals is rare. Because research which adopts a pipe flow and dynamic operational perspective is rare, a case application in Alexandria, Egypt collated empirical container and information flows using interviews and company records to describe its logistics processes and model container and information flows. The methodology used includes qualitative and quantitative methods and a descriptive methodology proceeds sequentially. Primary and secondary data were presented as a pipe flow model to show interrelations between the company’s resources and to identify bottlenecks. Simulation modelling used Simul8 software. Operational level modelling of both import and export flows simulated the actual inbound and outbound flows of containers from entry to exit. The import logistics process includes activities such as unloading vessels by quay cranes, moving containers by tractors to yard cranes to go for storage where customs procedures take place before exiting the terminal by customer’s truck. The export logistics process includes the activities associated with customers’ trucks, lifters, storage yards, tractors and quay cranes. The model takes into account the uncertainties in each activity. This study focuses on operational aspects rather than cost issues, and considers container flows rather than vessel flows. Although the simulated model was not generalized, implementation elsewhere is possible. Following successful validation of a base simulation model which reproduces the case company’s historical scenario, scenario testing empowered the case company to pro-actively design and test the impact of operational changes on the entire logistics process. The study evaluates a typical container terminal logistics system including both import and export containers in the presence of multiple uncertainties in terminal operations (e.g. quay crane operations, tractor operations, yard crane operations). Sensitivity testing and scenario analysis can empower terminal managers to make decisions to improve performance, and to guide terminal planners, managers, and operators in testing future investment scenarios before implementation.
219

Investigating the influence of individual value systems and risk propensities on decision-making quality in value clashing circumstances

Prinsloo, Christoffel Frederick January 2017 (has links)
This study investigated the influences of personal value systems and risk propensities on managerial decision-making quality during value clashes. The post-globalisation business landscape is impacted by role players of vastly differing personal attributes, hypothesised to have varying influences on decision-making behaviour. A deeper understanding of how these attributes impact decision-making quality will therefore enrich the literature and arm practitioners with improved decision-making skills. A review of behavioural decision-making literature revealed three core approaches: the normative (prescriptive) perspective, focussed on decision analysis, the cognitive limitations perspective highlighting the boundaries of human cognition and the psychological (values/emotions/motivations) perspective allowing for ethical- or value-boundedness. The extant literature contributes little on the quality of decision-making exhibited by managers, or how to improve it. It also doesn’t consider variance in decision-making between groups defined by personal value and risk traits. This study therefore aimed to establish whether decision-making quality varied with variances in personal attributes, and whether an intervention would improve decision-making behaviour. The research, conducted on a sample of 460 South African managers, established the demographics and value- and risk orientations of the participating group. Three value clashing scenarios, incorporating social-relational framing interventions, where introduced to gauge the decision-making behaviour of the test subjects. Decision-making quality was assessed through the integrative complexity measure and qualitative assessments were conducted on the decision motivation texts. Decision-tree analyses, multiple regression analyses as well as T-tests comparing the decision-quality produced by individuals of opposing orientations, revealed a clear relationship between the value segments of self-enhancement and openness to change and higher quality decision-making. Social risk-taking was related to better decision-making and reframing the scenarios produced better decision-making quality responses, if the reframing was done harshly enough. The qualitative analysis supported these findings, but hinted at additional, context specific decision motivators. This study contributed an integrated view of decision-making literature, tested the application of integrative complexity as a measure of decision quality and introduced new perspectives on how value orientations, risk proclivities and scenario framing relate to decision-making quality. Practitioners can apply this to assess individuals in terms of their decision-making abilities, and can improve decision-making quality in managers through scenario re-framing. / Thesis (PhD)--University of Pretoria, 2017. / Gordon Institute of Business Science (GIBS) / PhD / Unrestricted
220

Sustainability assessment of nuclear power in the UK using an integrated multi-criteria decision-support framework

Youds, Lorraine Helen January 2013 (has links)
In the UK, the debate surrounding energy production lies at the forefront of the political agenda, with growing emphasis on achieving an increasingly sustainable energy mix into the future. The nuclear option is especially debatable - issues such as waste management and decommissioning receive much attention. In addition, the many stakeholders interested in nuclear power display very divergent views on its sustainability. Since the turn of the century, nuclear power has received much attention globally, with many nations’ governments taking consideration of the potential benefits of new nuclear adoption. Conversely, the Fukushima nuclear disaster has led to new nuclear resistance in other nations, such as Germany, where plans have been made to stop nuclear power generation completely. This research aims to help inform the debate on nuclear power and the future UK electricity mix. A multi-criteria decision support framework (developed by the SPRIng Project) has been used for these purposes, taking into account technical, economic, environmental and social criteria.The methodology used in this work has involved: stakeholder consultation; use of future electricity scenarios; sustainability assessment of current and future electricity options (Pressurised Water Reactor, European Pressurised Reactor, European Fast Rector, coal, gas, solar and wind power, and coal carbon capture and storage [CCS] power); assessment of future electricity scenarios based on both sustainability impacts and stakeholder (expert and public) preferences for the sustainability indicators and electricity technologies. The sustainability assessment of future nuclear power options and coal CCS power have been carried out here for the first time in a UK-specific context.Based on the public and expert opinions on the importance of different sustainability indicators, results of the scenario analysis suggest that the scenario with a high penetration of low-carbon technologies (nuclear [60%] and offshore wind power [40%]) is the most sustainable. For the sample considered in this study, this finding is not sensitive to different stakeholder and public opinions on the importance of the sustainability indicators. However, when the stakeholder preferences for individual technologies are considered, scenarios with high penetration of renewables (26-40% solar and 20-48% wind) become the preferred options. This is due to the favourable stakeholder opinion on solar and wind power. In that case, the scenario with high penetration of nuclear is never the preferred option due to the low to moderate stakeholder preference for nuclear power.Therefore, the results from this research suggest that the ‘sustainability’ of different electricity options and scenarios is highly dependent on stakeholder preferences and priorities. Thus, for successful future deployment of these options and implementation of energy policy measures, transparency of information on the impacts of electricity options is key in ensuring that stakeholder opinions are founded in the actual rather than the perceived impacts of these options.

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