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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.
11

Factors Affecting Juvenile Movement in a House Sparrow Metapopulation

Myhre, Ane Marlene January 2012 (has links)
Dispersal propensity can vary considerably between individuals in a population. Understanding which individuals disperse- and under what circumstances these individuals disperse is valuable for conservation. Factors influencing juvenile movement and natal dispersal were studied in individually marked house sparrows, Passer domesticus, in an archipelago off the coast of Helgeland, northern Norway. Sex, clutch size, body size and body mass did not significantly explain variation in movement. Movement rate was however negatively related to hatch date on one of the islands. Moreover, there was a decrease in movement rate with increasing patch isolation and hostility of the matrix habitat. This study suggests that habitat configuration is an important factor determining movement of juvenile house sparrows, and that the environment experienced early in life may be related to movement propensity. I strongly recommend incorporating landscape features in further analyses of movement and dispersal rate.
12

The effect of hydropeaking on density, diversity and species richness of mayflies (Ephemeroptera) and stoneflies (Plecoptera) in two river systems

Herland, Anne Karine January 2012 (has links)
Hydropeaking corresponds to the management of hydropower resources where electricity is produced in accordance with prices and demand. Although fully justified economically, hydropeaking may have adverse consequences for the aquatic ecosystem. Due to frequent and rapid fluctuations in water discharge hydropeaking could generate negative effects on the ecosystem downstream the outlet of the hydropower station. Frequent fluctuations in water discharge, altered temperature regime, substrate composition and vegetation cover can result in reduced macroinvertebrate density and variety downstream the outlet of hydropower stations. Furthermore, macroinvertebrates inhabiting the shallow zone could be exposed to stranding as a consequence of frequent dewatering of the river-margin.In order to provide environmental guidelines for the hydropower industry, it is essential to understand how changes brought upon hydropeaked rivers affect the aquatic ecosystem.We studied the effect of hydropeaking on the total macroinvertebrate density and on the density, diversity and species richness of the orders Ephemeroptera and Plecoptera in two hydropeaked rivers, the Bævra River and the Lundesokna River, in central Norway. Findings from the given study demonstrated negative effects on the macroinvertebrates, likely caused by hydropeaking. The results showed a lowered total density and a lowered density, diversity and species richness of Ephemeroptera and Plecoptera in the locations exposed to frequent dewatering. In the permanently water covered location, however, there was less indication of a hydropeaking effect. These findings suggest that hydropeaking prevent establishment of normal benthic macroinvertebrate communities in the exposed shallow location, while the macroinvertebrate fauna in the permanently water covered location are less affected.
13

Fitness consequences of selection of home range in moose (Alces alces)

Klaussen, Ada Johanne January 2012 (has links)
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14

Integration of Methods for Environmental Assessment and Investment Analysis

Grytli, Tuva January 2010 (has links)
<p>Background, aim and scope. In this thesis a framework for integrating life cycle assessment and investment analysis is derived, aimed to (1) unite economic and environmental perspectives, and (2) strengthen system borders. The application of the model is shown in a case study of a bioenergy facility in central Norway. Prices and environmental impacts are calculated, and the results are compared to those for electricity generated from natural gas. Two examples of utilisation of the results are presented. Methods. Hybrid life cycle assessment is employed to enable the use of the price model from input-output analysis. The price model is extended to facilitate the integration of investment analysis. The resulting framework embodies all aspects from investment analysis, including tax and discounting. The result is a model performing a state of the art hybrid life cycle assessment and a net present worth analysis to obtain environmental and economic results with consistent system borders. Application. The method is applied to a case study, evaluating an electricity generating bioenergy facility in central Norway. The bioenergy facility was found to be a viable investment. Using bioenergy as an abatement measure against global warming was found to be competitive against carbon credits in the case of CO2 quota prices at the level assumed in 2030. Results and discussion. The model produced robust results comparable to those found in other studies. The framework proved to have several advantages in addition to strengthened system borders; amongst others a mutual empowerment between the two base analyses in relation to decision making, and a possibility for establishing eco-efficiency indicators.</p>
15

Development and assessment of symiosis in an industrial park

Hjelm, Øystein January 2007 (has links)
<p>As weather records are broken, and the topic of global warming and climate change, focus has been set on how this current development could be slowed or stopped. A change in paradigm must be conducted in order to address sustainable development. This paper has focused on how the field of industrial ecology and the tool of eco-industrial parks could be used to improve environmental performance of industrial systems. To evaluate the methods an industrial area at Moss has been further developed and new processes have been introduced. The system consists of an oxy-fuel CHP with carbon dioxide capture using the landfill gas as fuel, a urea plant, an ammonia plant to deliver ammonia to the urea plant and a cryogenic air separator plant providing nitrogen to the ammonia plant and pure oxygen to the CHP. Some carbon dioxide not used in the urea plant is used to increase the growth in a greenhouse. To evaluate the system, two simulation tools have been used. HYSYS has been used to simulate the processes involved and to arrange data for flow analysis. The heat exchanges had been assessed using Pro Pi 1, a tool specifically designed to create composite curves. Several simplifications have been made to easy the simulation. The CHP has an electric efficiency of 27 per cent and a total efficiency of 73,8 per cent. The electric exergy efficiency of the CHP is 28 per cent with a total system exergy efficiency of 67,7 per cent. The proposed system emits 35 per cent less carbon dioxide compared with stand alone processes. The system produce more heat then is needed to cover almost every process, and also the total demand in both the low- and high temperature district heating. The only process in need of external heating is the syngas reformer, which operates at such a high level that a stream of 46 kg/h of methane must be added. The output form the park is 8120 tonnes of urea annually, based on 8000 operating hours. The composite curves used to describe the heat exchange in the system proved to be a valuable tool when evaluating the need for utilities in the system. Both the material and energy flow analysis provided a good way to present energy and resource flows in the system. However, the exergy flow analysis proved to lack well developed tools to include irreversibility connected to the flows. Based on the guidelines presented from the Kalundborg EIP, the designed system could be called an eco-industrial park. However, economic analysis must be conducted to explore if there are economic incentives for the companies to develop such a park. Based on the experiences in this paper, further research should be made to develop better tools to calculate exergy losses based on HYSYS simulations. Also, an assessment of the economics connected to the system should be conducted.</p>
16

Integrating LCA in the local energy planning for heat supply of buildings

Hammervold, Johanne January 2007 (has links)
<p>The objective of this study was to develop an approach to integrate LCA of different fuels and energy conversion technologies into the energy planning tool eTransport. Course LCA's for relevant energy commodities, infrastructure and transport services was performed, and the results from these prepared for implementation in eTransport. In the choice of methodology for integration, a lot of aspects needs consideration. These are described throughout the report and emphasized in the choice of methodology. The methodology is illustrated by a case study on Trondheim municipality, followed by a description on how this would be done in eTransport. This project is a groundwork regarding implementation of LCA in eTransport, and will be followed up by further student work, testing the method in practice.</p>
17

Combined life cycle and economic assessment of wood based bio fuels in Norway

Gryczon, Michal January 2008 (has links)
<p>The increasing global demand for energy coupled with decreasing oil-supplies, and increasing risk of adverse climate change due to anthropogenic carbon emissions has created the need for combined economic and environmental assessment. This thesis attempt at devising such a framework based upon Life Cycle Assessment (LCA) and Life Cycle Costing (LCC). These methodologies represent two well established approaches for measuring environmental and economic performance of industrial projects and products. The LCA framework permits introduction of system expansion by interfacing with the greater economy by the hybrid-LCA. This approach also permits the assessment of life-cycle costs within the mathematical structure. The fundamental computations of LCA and LCC are introduced in this text in order to establish the combined assessment framework. This assessment method is applied to two National Renewable Energy Laboratory's studies on bio-ethanol production from lignocellulose. The studies are adapted to Norwegian economic conditions in order to assess the price and emissions of ethanol production from Norwegian wood mass. By combining these performance characteristics, a mitigation price of substituting gasoline with ethanol is established for various plant sizes as well as prices of gasoline.</p>
18

Environmental Input-Output Assessment of Integrated Second Generation Biofuel Production in Fenno-Scandinavia

Gibon, Thomas January 2009 (has links)
<p>The goal of this study is to investigate the potential implementation of integrated dimethyl ether (DME) production from by-products of the pulp and paper industry in Fenno-Scandinavia (Finland, Norway and Sweden) and to quantify the consequences of several use scenarios in which fossil fuels were gradually substituted by DME. To that end, two analytical frameworks were jointly used, life cycle assessment (LCA) and environmentally-extended input-output analysis (EEIOA). The first framework was utilised to make an exhaustive inventory of the Chemrec process and its integration in the Finnish, Norwegian and Swedish contexts. The latter framework was employed in order to incorporate this production system into a multi-regional input-output model that has been created for the purpose of the study. For data availability reasons, the stressors that have been examined are anthropogenic carbon dioxide, methane and dinitrogen monoxide, widely regarded as the elements which are responsible for the most serious environmental impacts. Three different story lines (plus a baseline scenario) were taken into account: a resource assessment scenario, in which a total implementation is assumed; a policy-independent approach setting a constant increase in the use of biofuels and a policy-compliance approach, aiming at satisfying European directive goals. It results that 5.21 to 20.6 Mt of DME can be produced, while the range of greenhouse gases emissions that can be saved thanks to a black liquor-based DME production scheme goes from 46.7 (scenario 3) to 70.5 (scenario 2) Mt in 2050, that is, 8.15–12.8% out of the otherwise total emissions in Fenno-Scandinavia. This LCA/IO analysis emphasises that the amount of greenhouse gases emissions embodied in every kg of DME highly depends on each country's background economy and evolves considerably along the decade, unit-level analysis show drastic reductions (-15% to -57% between 2000 and 2050) in DME embodied emissions. A nationwide analysis highlights a very important potential from the Finnish pulp and paper industry. All in all, it shows that such a biofuel production scheme should be implemented in countries that have an remarkable environmental profile to obtain very significant environmental performances. Only a joint effort of all the key sectors (energy, transportation, households) can lead to climate change mitigation and energy security.</p>
19

Hybrid Life Cycle Assessment of Wood-based Biofuel Production and Consumption Scenarios in Norway

Bright, Ryan January 2008 (has links)
<p>An increasingly urgent need to develop alternatives to fossil fuels in road trans- portation stems from both the need to combat climate change and the need to prepare for a transition beyond peak oil. Biofuels can be part of an al- ternative solution to both. In Norway, the boreal forest o®ers a considerable resource base, and emerging technologies may soon make it commercially vi- able to convert these resources into low-carbon biofuels. Therefore, it is critical that policy-makers are provided with the knowledge needed to make informed decisions regarding the environmentally sustainable production of wood-based biofuels in Norway over near- and mid-term time horizons. A combined supply-demand resource assessment was performed to map the resource base and to quantify the wood-based bioenergy potential in Norway. A set of selected conversion technologies were chosen and evaluated for a series of scenarios addressing the utilization of woody-biomass resources through each of the systems. An integrated economic input-output LCA approach was taken to perform biofuel production-consumption scenario analyses in Norway up to 2050 in e®orts to quantify climate change mitigation and fossil displacement potentials. It was found that a growing resource base, when used to produce second generation biofuels, can displace anywhere from 35-50% of fossils used in land transport which can warrant signi¯cant AGW mitigation potential both from within road transport and other key sectors.</p>
20

Path Exchange Method for Hybrid Life-Cycle Assessment

Baboulet, Olivier January 2009 (has links)
<p>To keep process-specificity while extending system boundaries hybrid techniques were developed allowing the micro structure of the important parts of a system to be revealed at the same time the entire economic system in which the system is embedded to be covered. Despite the substantial improvements bestowed by hybrid techniques some downsides still hold. Tiered hybrid LCA first does not model feedbacks whereas the relationship between the process-based system and the input-output based system is interactive and second it may suffer from double counting incidents as a process may be instigated in both the IO and LCI data. Integrated hybrid LCA overcomes those aforementioned pitfalls but only at a price of high labor and data intensity. This work aims to elaborate a new hybridisation method that avoids previously mentioned drawbacks. This technique is designed to not operate anymore at the matrix level as is the case for current hybridisation techniques but at the structural path level, per se the finest level of detail possible for the disaggregation of the Leontief inverse, and as such an ad hoc basis to carry out an hybrid analysis. It is argued that the method presented here constitutes a culmination amongst hybridization techniques. Its operability and capabilities are demonstrated before an interpretation from an input-output vantage point is carried out on a case-study not to be found in the literature, a comparison across the faculties of a university.</p>

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