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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.
351

The simulation modeling of supply logistics of forest biomass in British Columbia

Mahmoudi, Mohammadhossein 11 1900 (has links)
The search for alternative energy sources has increased interests in forest biomass. During the last few years, the sever infestation of the Mountain Pine Beetle (MPB) within the Interior BC forests has led to huge volumes of dead wood that exceed the capacity of the lumber industry. One way to make the most value of the surplus wood is to use it as the feedstock for bioenergy. The forest biomass can be supplied through conventional (roadside residuals), full-tree chipping, or satellite yard systems. This thesis presents the development of a simulation model of supply logistics of forest biomass and its application to a case of supplying MPB-killed biomass from Quesnel Timber Supply Area (one of the most infested areas in the Interior BC) to a potential 300 MW power plant adjacent to the city of Quesnel. The model has the ability of providing estimates of quantity, delivery cost, and moisture content of biomass which are critical in feasibility study of any bioenergy project. The results obtained from simulation model showed a delivery cost of C$45 per oven dry tonne of wood chips to the power plant. The results also revealed that the feedstock recovered from roadside residues in one year meets about 30% of the annual demand of the power plant. Potential increase in the Allowable Annual Cut (AAC) for Quesnel TSA increases the quantity of biomass supplied from roadside residuals. However, as long as the biomass is supplied only through conventional harvesting, increasing the AAC even by 40% does not provide enough feedstock to meet the annual demand of the plant. Using the simulation modeling, this research has the benefit of considering the logistics of forest biomass supply as an integrated and interacting system as well as providing different critical parameters over time. The model also has the potential of considering dynamic and random behavior of the logistics system of supplying forest biomass. The model can be modified and applied to similar cases of conventional forest biomass supply. It also can be extended to other harvesting systems including satellite yard and whole-tree chipping.
352

An airborne Lidar canopy segmentation approach for estimating above-ground biomass in coastal eucalypt forests

Turner, Russell Sean, School of Biological, Earth & Environmental Science, UNSW January 2006 (has links)
There is growing interest in airborne lidar for forest carbon accounting and precision forestry purposes. Airborne lidar systems offer a cost-effective, versatile, operationally flexible and robust sampling tool for forest managers. The objective of this study was to develop and test lidar canopy surface enhancement and segmentation processes for estimating dominant above-ground biomass (DAB) in a harvested eucalypt forest on the Central Coast of New South Wales (Australia). The Crown Infill, Trim and Smooth (CITS) process, incorporating a series of filters, algorithms, and selective multi-stage smoothing, was used to enhance lidar canopy surfaces prior to segmentation. Canopy segmentation was achieved using a vertical crown template approach termed the Spatially and Morphologically Isolated Crest (SMIC) process. SMIC delineates dominant tree crowns by detecting elevated crown crests within a 3D lidar canopy surface. Consolidated crown units constitute the basic sampling, analysis and reporting units for wall-to-wall forest inventory. The performance, sensitivity and limitations of these procedures were evaluated using a combination of simulated forest models and actual lidar forest data. Automated crown polygons were used as a sampling template to extract dominant tree height values which were converted to DAB estimates via height-to-biomass relationships derived from field survey and on-site destructive sampling. Results were compared with field based tree height and biomass estimates. Compared against a manually derived crown map from a 2ha field plot, canopy segmentation results revealed a producer???s accuracy of 76% and overall accuracy of 67%. Results indicated a trend toward greater crown splitting (fragmentation) as trees increase in age, height, stem diameter and crown size. Extracted dominant tree height values were highly correlated with ground survey height estimates (r2 0.95 for precision survey and r2 0.69 for standard survey). There was also no significant difference between SMIC and manual crown height estimates. SMIC units overestimated ground-based DAB by 5%; this increased to 36% with the inclusion of segmentation errors. However, SMIC estimation of total plot above-ground biomass (AGB) was within 9% of the ground-based estimate. Results are encouraging considering the mixed-species, multi-aged composition of the forest, and the combined effects of SMIC segmentation and lidar height errors.
353

An integrated decision support tool for more sustainable management of biomass resources in agricultural regions

Jakrawatana, Napat, Civil & Environmental Engineering, Faculty of Engineering, UNSW January 2009 (has links)
Agriculture currently faces a number of environmental sustainability issues. Three key issues that are the focus of this study are greenhouse gas emissions, depletion of mineral phosphorus resources and cadmium contamination in agricultural soil. Biomass can potentially be used as a renewable energy source and can also be returned to improve the nutrient and drainage structure of agricultural soils. Sustainable management of biomass and agriculture can have significant impacts on reducing greenhouse gas emissions from a region. Moreover, it reduces the demand for external energy supply, phosphorous (P) based fertilizer, and it??s associated Cadmium (Cd) impurity which can contaminate the soil, plant and food chains. These three issues have typically been considered separately, and managed by different agencies or organisations. The aim of this thesis is to develop an integrated decision support tool that can be used for evaluating alternative options for management and resource recovery from biomass for enhancing recovery of energy, returning carbon (C) and phosphorus (P) from biomass back to soil, reducing greenhouse gas emissions and also cadmium (Cd) contamination in an agricultural region. This research employed a combination of the tools of Material Flow Analysis (MFA), Geographic Information System (GIS) and Cost-Benefit Analysis (CBA). MFA is used as the primary tool for this research. GIS and CBA are combined with MFA in later stages of the overall procedure to develop an integrated decision support tool. This integrated tool has been applied to the Murrumbidgee Irrigation Area (MIA) in Australia. Tracking the flow of essential substances using MFA has identified current resource management efficiency and substances accumulation across the region. Integrating a spatial analysis tool (GIS) with MFA has provided a feedback driven monitoring tool for evaluating trends of spatial accumulation of substances on agricultural land. This enables the time remaining before acceptable limits are exceeded to be estimated on a spatial basis. Integrated MFA and CBA has been applied to evaluate the tradeoffs and potential synergies of alternative biomass management options. Overall the tool can assist in evaluating the effectiveness of alternative scenarios and visualise the results to stakeholders in a systematic way.
354

Characterization of poultry litter for storage and process design

Bernhart, Matthew, January 2007 (has links) (PDF)
Thesis (M.S.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references (ℓ. 80)
355

The ethanol market an econometric inquiry into the market for E85 /

Tatum, Shaun Wesley, Jackson, John D. January 2007 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references.
356

Temperature influence and heat management requirements of microalgae cultivation in photobioreactors a thesis /

Mehlitz, Thomas Hagen. Yildiz, Ilhami, January 1900 (has links)
Thesis (M.S.)--California Polytechnic State University, 2009. / Mode of access: Internet. Title from PDF title page; viewed on March 18, 2009. Major professor: Ilhami Yildiz, Ph.D. "Presented to the faculty of California Polytechnic State University, San Luis Obispo." "In partial fulfillment of the requirements for the degree [of] Master of Science in Agriculture, with specialization in: Agricultural Engineering Technology." "February 2009." Includes bibliographical references (p. 115-122). Also available on microfiche.
357

Pretreatment and enzymatic hydrolysis of lignocellulosic biomass

Corredor, Deisy Y. January 1900 (has links)
Thesis (Ph.D.)--Kansas State University, 2008. / Advisers: Donghai Wang, Scott Bean. Includes bibliographical references.
358

Distinguishing between live and dead standing tree biomass on the North Rim of Grand Canyon National Park, USA using small-footprint lidar data /

Kim, YunSuk. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 37-41). Also available on the World Wide Web.
359

Defining sustainability : a case study of a woody biomass project in the Pacific Northwest /

Lode, Ben Raymond. January 2008 (has links)
Thesis (M.A.)--University of Oregon, 2008. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 109-111). Also available online.
360

The design of dialogue using soft systems methodology to examine the 'health' of stakeholder discourse around the development of biofuels in New Zealand whilst assessing how this approach could contribute to the improvement of decision-making processes : a thesis submitted to Auckland University of Technology (AUT) in fulfilment of the requirements for the degree of Master of Philosophy (MPhil), 2008.

Crowe, Peter. January 2008 (has links)
Thesis (MPhil) -- AUT University, 2008. / Includes bibliographical references. Also held in print (xi, 165 leaves : col. ill. ; 30 cm.) in the Archive at the City Campus (T 658.403 CRO)

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