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Sherry, John William. "Systems of arrogance: Technology and the work of Navajo resistance". Diss., The University of Arizona, 1995. http://hdl.handle.net/10150/187442.
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This dissertation adopts the perspective of Cognitive Ethnography to examine the work of a grassroots, Navajo environmental organization called Diné Citizens Against Ruining our Environment. Specifically, I will examine the work and the challenges facing the members of this organization in order to evaluate how new communications and information technologies may be of use to them. This analysis begins, as Cognitive Ethnography mandates, with a general description of the tasks which constitute the work of Diné CARE. As will be discussed, these consist primarily in attempts to reassert what the organization's members consider to be traditional Navajo perspectives on economic development and the human relationship with the natural environment. Subsequently, I analyze the representations, measurements of work, and forms of organization required to accomplish Diné CARE's tasks. In all aspects of the work, members were constantly required to manage a dialogue between their preferred means of organizing or representing work, and the means required by the operating environment in which they found themselves, characterized primarily by relationships with various outside sources of legal, technical or financial support. The work of Diné CARE is thus extensively "dialogic." While members continually drew on Navajo traditions for viewing the relationship of human beings to the natural environment, for representing their work, and for building cooperative access to resources for resistance, they were nonetheless required at the same time to position these "traditional" approaches against approaches whose history of development have political, social and cultural roots in Western Europe and modem America. Often, this dialogue brought with it tension and even morally charged conflict for the members of Diné CARE. This tension extended to emerging technologies as well. In spite of many claims to the contrary, new communications and information technologies did little to alleviate the mismatch between "local" and "foreign" ways of doing work. Instead of "empowering" local communities by providing them access to information or the chance to be heard on their own terms, new technologies complicated the scenario of local resistance by requiring practices for representing work which were both difficult to master and often inappropriate.
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Holt, Ryan Samuel. "Three enabling technologies for vision-based, forest-fire perimeter surveillance using multiple unmanned aerial systems /". Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd1894.pdf.
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Wang, Fei. "Design and implementation of Web-based GIS for forest fragmentation analysis". Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2473.
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Thesis (M.A.)--West Virginia University, 2002.Title from document title page. Document formatted into pages; contains xi, 107 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 100-107).
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Hewitt, Nina. "Plant dispersal and colonization in fragmented forest systems". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ43425.pdf.
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Brink, Michal. "Development of a method to forecast future systems in the forest engineering value chain". Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52188.
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Dissertation (PhD (For))--University of Stellenbosch, 2001.ENGLISH ABSTRACT: The objective of this study is to develop a new method which can be used to forecast the Forest Engineering value chain. The method is then applied in the South African context in order to validate the use thereof. Finally, the South African results are used to propose strategies, which the industry should pursue in the future. To forecast the future an understanding of the past is required. To this end, the historical development of Forest Engineering is discussed, both globally and in South Africa. The current status quo in Forest Engineering in South Africa was determined through a national survey of plantations larger than 200 ha. The results are reflected in Chapter 2. Because of the importance of globalisation and technology, Chapter 3 gives a literature review of relevance of technology in today's business world, including various forecasting techniques that are relevant to the study. These techniques are a combination of traditional forecasting methods, technology forecasting methods and strategic planning methods. Various approaches to financial analysis have also been discussed, in order to determine the soundest method of comparing various forest engineering systems with each other. This includes an overview of traditional machine cost calculations. The core of the study lies in the combination of these methodologies into a useful method, which is particularly suited to forecasting the Forest Engineering value chain. Such a method is developed in Chapter 4, based on the literature review of forecasting methodologies. The method is then validated in Chapter 5, through the application thereof in the South African forestry industry. Global trends are established with the use of a Delphi study. This technique uses a panel of experts who give their views on future developments on a multiple round basis. The study then evaluates 14 Forest Engineering systems for pine sawtimber, pine pulpwood and Eucalyptus pulpwood, based on various scenarios of the future. The scenario matrix is based on the future cost of labour vs. the future cost of machinery. Finally, a strategy is proposed on how the South African forestry industry should prepare itself for the future.
AFRIKAANSE OPSOMMING: Die doelwit van die studie is om 'n nuwe metode te ontwikkel waarmee 'n vooruitskatting van die Bosingenieurswese waardeketting gemaak kan word. Die metode word dan in die Suid-Afrikaanse konteks toegepas om die geldigheid daarvan te beproef. Die Suid-Afrikaanse resultate word voorts gebruik om 'n nasionale Bosingenieurswese strategie voor te stel vir die bedryf. Dit is nodig om die verlede te verstaan, voor die toekoms vooruitgeskat kan word. Om dié rede is die historiese ontwikkeling van bosingenieurswese bespreek, in beide 'n internasionale, sowel as 'n Suid Afrikaanse konteks. Die huidige status quo van Bosingenieurswese in Suid Afrika is vasgestel deur 'n nasionale opname waarby plantasies van groter as 200 ha ingesluit is. Die resultate van die opname word weergegee in Hoofstuk 2. As gevolg van die belangrikheid van beide globalisering en tegnologie, is 'n literatuur studie ingesluit in Hoofstuk 3 oor die relevansie van tegnologie in die besigheidswêreld van vandag, asook en 'n bespreking van verskeie vooruitskattingstegnieke wat in die studie gebruik kan word. Hierdie vooruitskattinge is 'n kombinasie van tradisionele vooruitskattings tegnieke, tegnologie vooruitskattingstegnieke en tegnieke wat gebruik word vir strategiese beplanning. Verskeie benaderinge tot finansiële analise is ook bespreek. Dit sluit tradisionele masjienkoste berekening in. Die rede hiervoor is om vas te stel watter metode die mees geskikte sou wees om verskeie Bosingenieurswese sisteme met mekaar te vergelyk. Die kern van die studie lê in die kombinasie van hierdie metodes om 'n bruikbare metode te ontwerp om die Bosingenieurswese waardeketting vooruit te skat. Hierdie ontwerp word in Hoofstuk 4 bespreek. Die metode word in Hoofstuk 5 beproef, deur die toepassing daarvan op die Suid Afrikaanse bosbedryf. Internasionale bosingenieurswese tendense is vasgestel deur middel van 'n Delphi studie. Hierdie vooruitskatting maak gebruik van 'n paneel van kundiges wat hulle siening oor die toekoms uitspreek deur verskeie rondtes van vrae wat aan hulle gestel word. Die studie evalueer hierna 14 Bosingenieurswese sisteme vir denne saaghout, denne pulphout en Eucalyptus pulphout, gebaseer op 'n scenario-analise van die toekoms. Die scenario matriks is gefundeer op die toekomstige koste van arbeid teenoor die toekomstige koste van masjinerie. As 'n finale stap word voorgestel hoe die Suid Afrikaanse bosbedryf kan voorberei om die toekoms tegemoet te gaan.
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Wallertz, Kristina. "Pine weevil Hylobius abietis feeding in shelterwood systems /". Alnarp : Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/10040784.pdf.
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Adams, Bryce Timothy. "Quantifying avian and forest communities to understand interdependencies of ecological systems and inform forest bird conservation". The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1531866781943962.
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Fragkoudis, Rennos. "Novel reporter systems to study Semliki Forest virus pathogenesis". Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/29767.
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Two different types of recombinant viruses each carrying one of two foreign genes, enhanced green fluorescent protein (eGFP) or Cre recombinase, were constructed based on the SFV4 backbone. In the first type of construct the transgene was inserted in the non-structural ORF, between the coding sequences for nsP3 and nsP4, flanked by processing sites recognised by the nsP2 proteinase. In the second type of constructs the 2A sequence from foot-and-mouth disease virus was added to the C-terminus of the foreign gene and this was placed between the capsid and the p62 protein of SFV4 (structural ORF). All recombinant viruses constructed were viable and able to replicate in vitro. eGFP expressing viruses reached titres similar to those of wild-type virus whereas Cre expressing viruses were slightly attenuated. For viruses with the marker gene inserted in the non-structural ORF, western blotting showed that the processing pattern of the non-structural polyprotein was similar to that of SFV4 and verified the expression of both foreign genes. In vivo, following intracerebral inoculation, all viruses caused encephalitis. Viruses expressing the foreign gene as a cleavable component of the structural ORF induced disease slower than SFV4 or viruses carrying the transgene in the replicase ORF. eGFP fluorescence was stronger and occurred later in infection when expressed in the structural ORF than in the replicase ORF. eGFP expression from the replicase ORF marked only recently infected cells; a property useful in pathogenesis studies. eGFP expressing viruses demonstrated the same cell tropism as SFV4 with infection principally of neurons and oligodendrocytes. None of the mice infected intraperitoneally with SFV4 or the recombinant viruses succumbed to infection demonstrating poor neuroinvasiveness. These viruses are likely to be highly valuable for in vivo pathogenesis studies.
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Söderström, Simon. "Detect obstacles for forest machinery from laser scanned data". Thesis, Umeå universitet, Institutionen för fysik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-174911.
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Borona, Gloria Kendi. "Investigating people-forest relationships around central Kenya's Nyandarwa forest reserve : understanding their sustainability through indigenous knowledge systems". University of British Columbia, 2017. http://hdl.handle.net/2429/63770.
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This study explored how people-forest relationships are forged around Kenya’s Nyandarwa Forest Reserve, and how Indigenous Knowledge Systems of Agĩkũyũ people around the Reserve might contribute to healthy, sustainable people-forest relationships in light of the country’s changing social, economic, and political situations. The study sought to examine:1) how the indigenous communities around Nyandarwa Forest Reserve traditionally understood and sustained interdependencies with the forest; 2) how these interdependencies have transformed consistent with Kenya’s post-independence changes in social, economic, and political situations; 3) to what extent local, national, and international efforts to promote healthy sustainable people-forest relationships are incorporating local communities’ Indigenous Knowledge Systems (IKS); and, 4) how these communities’ IKS might inform the proposition of an environmental conservation framework for sustainable people-forest relationships.
The study was guided by post-colonial indigenous research paradigms anchored in decolonizing methodologies. These methodologies were buttressed by indigenous theories that consider communities as spiritual beings with multiple relations. The study was informed by the traditions and cultural heritage of the Agĩkũyũ people, and augmented by Afrocentric philosophies that underlie African ways of knowing and value systems. Data were collected from community groups, elders, the Kenya Forest Service, and archives. The data corpus was analyzed using NVIVO consistent with the study’s theoretical framework and generated themes that address the research questions. In addition, the research participants contributed to the process as this study sought to elevate the community to the role of co-researchers and to create mutually beneficial long-term relationships.
Results show that the pre-colonial manifestation of Agĩkũyũ people-forest relationships were understood through land, that land continues to be a central pillar of Agĩkũyũ indigenous environmental thought, and that one of the historical values of the forest is its role in sustaining the struggle for independence. Further, the study reveals that some indigenous practices tied to sacred sites and food sovereignty have endured, different governance regimes have shifted the way people-forest relationships are constructed, and the Agĩkũyũ have been continuously mobilizing to protect their landscape. In the end, this study suggests how IKS can contribute to forging sustainable people-forest relationships, arguably the planet’s most threatened resource.Forestry, Faculty of
Graduate
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Näslund, Eriksson Lisa. "Forest-Fuel Systems : Comparative Analyses in a Life Cycle Perspective". Doctoral thesis, Mittuniversitetet, Institutionen för teknik och hållbar utveckling, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-206.
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Forest fuels can be recovered, stored and handled in several ways and these different ways have different implications for CO2 emissions. In this thesis, comparative analyses were made on different forest-fuel systems. The analyses focused on the recovery and transport systems. Costs, primary energy use, CO2 emissions, storage losses and work environment associated with the use of forest fuel for energy were examined by using systems analysis methodology in a life cycle perspective. The bundle system showed less dry-matter losses and lower costs than the chip system. The difference was mainly due to more efficient forwarding, hauling and large-scale chipping. The potential of allergic reactions by workers did not differ significantly between the systems. In difficult terrain types, the loose material and roadside bundling systems become as economical as the clearcut bundle system. The stump and small roundwood systems showed the greatest increase in costs when the availability of forest fuel decreased. Stumps required the greatest increase in primary energy use. Forest fuels are a limited resource. A key factor is the amount of biomass recovered per hectare. Combined recovery of logging residues, stumps and small roundwood from thinnings from the same forest area give a high potential of reduced net CO2 emissions per hectare of forest land. Compensation fertilization becomes more cost-effective and the primary energy use for ash spreading becomes low – about 0,25‰. The total amount of available forest fuel in Sweden is 66 TWh per year. This would cost 1 billion €2007 to recover and would avoid 6.9 Mtonne carbon if fossil coal were replaced. In southern Sweden almost all forest fuel is obtainable in high-concentration areas where it is easy to recover. When determining potential CO2 emissions avoidance, the transportation distance was found to be less important than the other factors considered in this work. The type of transportation system did not have a significant influence over the CO2 avoided per hectare of forest land. The most important factor analysed here was the type of fossil fuel (coal, oil or natural gas) replaced together with the net amount of biomass recovered per hectare of forest land. Large-scale, long-distance transportation of biofuels from central Sweden has the potential to be cost-effective and also attractive in terms of CO2 emissions. A bundle recovery system meant that more biomass per hectare could be delivered to end-users than a pellet system due to conversion losses when producing pellets.
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Williams, Alyssa. "Hybrid Recommender Systems via Spectral Learning and a Random Forest". Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etd/3666.
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We demonstrate spectral learning can be combined with a random forest classifier to produce a hybrid recommender system capable of incorporating meta information. Spectral learning is supervised learning in which data is in the form of one or more networks. Responses are predicted from features obtained from the eigenvector decomposition of matrix representations of the networks. Spectral learning is based on the highest weight eigenvectors of natural Markov chain representations. A random forest is an ensemble technique for supervised learning whose internal predictive model can be interpreted as a nearest neighbor network. A hybrid recommender can be constructed by first deriving a network model from a recommender's similarity matrix then applying spectral learning techniques to produce a new network model. The response learned by the new version of the recommender can be meta information. This leads to a system capable of incorporating meta data into recommendations.
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Purbopuspito, Joko. "Trace gas emissions from forest and land-use systems at the tropical forest margins in Central Sulawesi, Indonesia /". Göttingen : Cuvillier, 2005. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=013522791&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Park, Pil Sun. "Forest stand structure characteristics for the Cispus adaptive management area, Cascade Range, U.S.A. : implications for old growth, fire hazard, silviculture, and landscape management /". Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/5587.
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Wallerman, Jörgen. "Remote sensing aided spatial prediction of forest stem volume /". Umeå : Dept. of Forest Resource Management and Geomatics, 2003. http://epsilon.slu.se/s271.pdf.
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Bergström, Dan. "Techniques and systems for boom-corridor thinning in young dense forests". Umeå : Dept. of Forest Resource Management, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200987.pdf.
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Obare, Lynette Adhiambo. "Forest user needs, gender, and geographic information systems : an integrative approach to managing the Forest of the Lost Child". Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19573.
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This thesis is a critical examination of the history of philosophies governing public education in the United States. The first half, chapters one through six, outlines American conceptions of the role of the school in relation to the state and to democracy. The second half is an account of critical progressive philosophies that have challenged the American status-quo since the independence. The main argument that I propose here is that the creation of an education system in America has followed the philosophies of federalism and private democracy. These philosophies are economically centered and define the citizen in economic terms. Progressive educators have long questioned this definition and seek to redefine citizenship to describe participatory democracy, and communication based on experience and an ethic of care.
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Mercier, Wilfred Jean-Baptiste. "Generation of Forest Stand Type Maps Using High-Resolution Digital Imagery". Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/MercierWJB2009.pdf.
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Hishi, Takuo. "Architecture and function of fine root systems in a forest ecosystem". Kyoto University, 2005. http://hdl.handle.net/2433/145038.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第11638号
農博第1494号
新制||農||908(附属図書館)
学位論文||H17||N4031(農学部図書室)
23281
UT51-2005-D387
京都大学大学院農学研究科地域環境科学専攻
(主査)教授 武田 博清, 教授 谷 誠, 教授 東 順一
学位規則第4条第1項該当
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Blessing, Sithole Vhusomuzi. "A multiscale remote sensing assessment of subtropical indigenous forests along the wild coast, South Africa". Thesis, Nelson Mandela Metropolitan University, 2015. http://hdl.handle.net/10948/d1021169.
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The subtropical forests located along South Africa’s Wild Coast region, declared as one of the biodiversity hotspots, provide benefits to the local and national economy. However, there is evidence of increased pressure exerted on the forests by growing population and reduced income from activities not related to forest products. The ability of remote sensing to quantify subtropical forest changes over time, perform species discrimination (using field spectroscopy) and integrating field spectral and multispectral data were all assessed in this study. Investigations were conducted at pixel, leaf and sub-pixel levels. Both per-pixel and sub-pixel classification methods were used for improved forest characterisation. Using SPOT 6 imagery for 2013, the study determined the best classification algorithm for mapping sub-tropical forest and other land cover types to be the maximum likelihood classifier. Maximum likelihood outperformed minimum distance, spectral angle mapper and spectral information divergence algorithms, based on overall accuracy and Kappa coefficient values. Forest change analysis was made based on spectral measurements made at top of the atmosphere (TOC) level. When applied to the 2005 and 2009 SPOT 5 images, subtropical forest changes between 2005-2009 and 2009-2013 were quantified. A temporal analysis of forest cover trends in the periods 2005-2009 and 2009-2013 identified a decreasing trend of -3648.42 and -946.98 ha respectively, which translated to 7.81 percent and 2.20 percent decrease. Although there is evidence of a trend towards decreased rates of forest loss, more conservation efforts are required to protect the Wild Coast ecosystem. Using field spectral measurements data, the hierarchical method (comprising One-way ANOVA with Bonferroni correction, Classification and Regression Trees (CART) and Jeffries Matusita method) successfully selected optimal wavelengths for species discrimination at leaf level. Only 17 out of 2150 wavelengths were identified, thereby reducing the complexities related to data dimensionality. The optimal 17 wavelength bands were noted in the visible (438, 442, 512 and 695 nm), near infrared (724, 729, 750, 758, 856, 936, 1179, 1507 and 1673 nm) and mid-infrared (2220, 2465, 2469 and 2482 nm) portions of the electromagnetic spectrum. The Jeffries-Matusita (JM) distance method confirmed the separability of the selected wavelength bands. Using these 17 wavelengths, linear discriminant analysis (LDA) classified subtropical species at leaf level more accurately than partial least squares discriminant analysis (PLSDA) and random forest (RF). In addition, the study integrated field-collected canopy spectral and multispectral data to discriminate proportions of semi-deciduous and evergreen subtropical forests at sub-pixel level. By using the 2013 land cover (using MLC) to mask non-forested portions before sub-pixel classification (using MTMF), the proportional maps were a product of two classifiers. The proportional maps show higher proportions of evergreen forests along the coast while semi-deciduous subtropical forest species were mainly on inland parts of the Wild Coast. These maps had high accuracy, thereby proving the ability of an integration of field spectral and multispectral data in mapping semi-deciduous and evergreen forest species. Overall, the study has demonstrated the importance of the MLC and LDA and served to integrate field spectral and multispectral data in subtropical forest characterisation at both leaf and top-of-atmosphere levels. The success of both the MLC and LDA further highlighted how essential parametric classifiers are in remote sensing forestry applications. Main subtropical characteristics highlighted in this study were species discrimination at leaf level, quantifying forest change at pixel level and discriminating semi-deciduous and evergreen forests at sub-pixel level.
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Hussein, Marwan. "Absolute localization of mobile robots in forest environments by correlating ground LiDAR to overhead imagery". Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/91877.
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Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2014.Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014.
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Cataloged from PDF version of thesis.
Includes bibliographical references (pages 135-140).
A method for the autonomous geolocation of ground vehicles in forest environments is presented. The method provides an estimate of the global horizontal position of a vehicle strictly based on finding a geometric match between a map of observed tree stems, scanned in 3D by Light Detection and Ranging (LiDAR) sensors onboard the vehicle, to another stem map generated from the structure of tree crowns analyzed from aerial orthoimagery of the forest canopy. Identification of stems from 3D data is achieved by using Support Vector Machine (SVM) classifiers and height above ground filters that separate ground points from vertical stem features. Identifications of stems from overhead imagery is achieved by calculating the centroids of tree crowns extracted using a watershed segmentation algorithm. Matching of the two stem maps is achieved by using a robust Iterative Closest Point (ICP) algorithm that determines the rotation and translation required to align both datasets. The final alignment is used to calculate the absolute location of the vehicle. The localization algorithm has been tested with real-world data and has been able to estimate vehicle geoposition with errors of less than 2.1 m RMS. It is noted that the algorithm's accuracy is currently limited by the accuracy and resolution of the aerial orthoimagery used. This method can be used in real-time as a complement to the Global Positioning System (GPS) and Simultaneous Localization and Mapping (SLAM) in areas where signal coverage is inadequate due to attenuation by the forest canopy, or due to intentional denied access. The method has two key properties that are significant: i) It does not require a priori knowledge of the area surrounding the robot. ii) Based on estimated vehicle state, it uses the geometry of detected tree stems as the only input to determine horizontal geoposition.
by Marwan Hussein.
S.M. in Engineering and Management
S.M.
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Wakjira, Dereje Tadesse. "Governance of social-ecological systems in an Afromontane forest of southeast Ethiopia : exploring interactions between systems". Thesis, University of Aberdeen, 2013. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=205392.
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Adaptive governance is increasingly regarded as necessary to improve the resilience of social-ecological systems. However, empirical studies of social-ecological systems are scarce, especially in relation to multiple-use forest systems. This thesis draws on a study of an Afromontane forest in southeast Ethiopia that has been used by humans through history, and explores mechanisms of interactions between social and resource systems and their influences on the overall social-ecological system. The thesis analyses the role of local-level institutions in this social-ecological system, their changes over time, their function as channels of access to forest products for local people and their influence on the forest system resulting from people's patterns of forest use. I use an interdisciplinary approach, considering local governance institutions (Chapters 2 & 3), forest-based livelihoods (chapter 4) and forest system (Chapter 5) as components of social-ecological systems. Chapter 2 analyses institutional change over time in order to understand mechanisms by which local forest use has been coordinated in dynamic political and socio-economic contexts. Data were collected through in-depth and semi-structured interviews. The findings show that combining elements from both informal and formal institutions allowed traditional rules to persist for decades in the guise of more formal arrangements. However, large-scale governance changes constrained the adaptive capacity of local institutions by abolishing fora for collective decision-making. Chapter 3 builds on these findings. It examines the roles of elders, i.e., key actors in the communities, and the structure of their networks in order to understand mechanisms by which informal institutions were coordinated across study villages in the absence of fora for collective decision-making. Key informant in-depth interviews were used to explore the roles of elders in local governance. In addition, a questionnaire survey was conducted with elders to identify social networks. Findings suggest that prominent elders resident in different Kebeles were connected by layers of informal networks through which they exchanged opinions and knowledge. These networks were not centralised and were to some degree redundant, as the same roles were preformed by more than one elder in each community, which contributed to the persistence of informal institutions. These informal networks created a power that helped local people to undermine some of the formal rules and to continue using the forest for their livelihoods under informal governance arrangements. Chapter 4 investigates households' access to forest-based livelihoods as coordinated by informal institutions. To examine the relationships between households' endowments with assets and their use of forest products, a questionnaire survey was administered to the selected households resident in seven of the eight villages (Kebeles) bordering the Harenna forest. The results showed that 86% of households benefited from the forest directly by using one or more of the three non-timber forest products (NTFPs) considered; coffee, beekeeping and livestock grazing. Furthermore, there was no strong evidence that ownership of specific assets explained the difference between those households who used NTFPs and those who did not. However, asset-rich households tended to own larger areas of coffee land and to use multiple forest products compared to asset-poor households. In conclusion, future management approaches should be mindful of the effect that a formalisation of de facto forest use could have on widening the gap between asset-poor and asset-rich households. Chapter 5 reports the ecological legacy of different forest use practices. To assess the vegetation structure and composition of the forest under four different coffee management systems which evolved in the past 50 years, measurements of woody plants were taken from 202 nested plots. The results of the study provide an indication of how well each of the four coffee systems affects structure and composition of the forest. The study highlights the importance of adapting institutions to retain the patchy distribution of the different coffee systems in order to encourage forest dynamics at a landscape level. Together, the findings of the four studies identify the mechanisms by which interventions that specifically target either only forest ecosystems or social systems may undermine the sustainability of social-ecological systems. This emphasises the importance of autonomous local institutions to facilitate adaptive governance within broadly agreed goals, as rigid governance arrangements constrain the resilience of social-ecological systems.
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Long, Charles R. "Production and cost analysis of two harvesting systems in central Appalachia". Morgantown, W. Va. : [West Virginia University Libraries], 2003. http://etd.wvu.edu/templates/showETD.cfm?recnum=2877.
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Thesis (M.S.)--West Virginia University, 2003.Title from document title page. Document formatted into pages; contains vii, 80 p. : ill. Includes abstract. Includes bibliographical references (p. 62-67).
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Wang, Zhiming. "Stability and predictability of diameter distributions in a managed uneven-aged oak forest /". free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9841345.
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Almer, Oscar Erik Gabriel. "Automated application-specific optimisation of interconnects in multi-core systems". Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7622.
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In embedded computer systems there are often tasks, implemented as stand-alone devices, that are both application-specific and compute intensive. A recurring problem in this area is to design these application-specific embedded systems as close to the power and efficiency envelope as possible. Work has been done on optimizing singlecore systems and memory organisation, but current methods for achieving system design goals are proving limited as the system capabilities and system size increase in the multi- and many-core era. To address this problem, this thesis investigates machine learning approaches to managing the design space presented in the interconnect design of embedded multi-core systems. The design space presented is large due to the system scale and level of interconnectivity, and also feature inter-dependant parameters, further complicating analysis. The results presented in this thesis demonstrate that machine learning approaches, particularly wkNN and random forest, work well in handling the complexity of the design space. The benefits of this approach are in automation, saving time and effort in the system design phase as well as energy and execution time in the finished system.
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Hor, Sanara. "The Transition of Farming Systems Causing Forest Degradation in Ratanakiri Province, Cambodia". 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/193593.
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Sodja, Eric P. "Effects of Soil-Borne Pathogens on Seedling Establishment Patterns in Forest Systems". DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7703.
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The Janzen-Connell mechanism is proposed to maintain plant diversity: predators and diseases of seeds reduce the number of seeds that survive near a parent tree, but allow seeds far from the parent tree to grow into adulthood. In the area where seeds don’t survive, seedlings from other tree species which are not affected by the seed consumer can grow. At large scales, this effect is thought to increase overall plant diversity. Soil-borne pathogens can contribute to seed mortality in this way, but we don’t know how important different parts of their lifecycle are in creating Janzen-Connell patterns. To determine the role of soil-borne pathogens in the development of Janzen-Connell patterns, we constructed a simulation model to examine how tree and pathogen characteristics affect plant spatial patterns. Under specific combinations of tree and pathogen characteristics, we found that pathogens could create Janzen-Connell patterns. The most important parameters were how far trees dispersed their seeds, and how many seeds a tree produced in a year. These characteristics determined how much of an impact the pathogens were able to have on the tree population because they rely on the density of seeds to determine how far they can spread and how many spores they will produce.
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Sangay. "Analysis of silvicultural systems for the management of broadleaved hardwood forest in Bhutan, a case from Korila Forest Management Unit, KFMU". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0010/MQ30023.pdf.
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Moffat, Andrea C. "Forest certification, an examination of the compatibility of the Canadian Standards Association and Forest Stewardship Council systems in the Maritime region". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ36518.pdf.
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Pertuzé, Salas Julio Alberto. "Strategic change and the coevolution of industry-university relationships : evidence from the forest products industry". Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/89870.
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Thesis: Ph. D., Massachusetts Institute of Technology, Engineering Systems Division, 2014.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 261-287).
In this thesis we present an analysis of the dynamics of industry-university relationships tracing the origin of the relationship and its changes over time as the firm's strategies evolve. We analyze the strategic trajectories of nine European and North American forest products companies, distilling four generic strategies, and linking those strategies to each company's university relationships as judged by publications records, academic trajectories of the company's personnel, and interviews with company managers. We found that firms are likely to form new university relationships when (1) integrating new positions in the value chain, (2) diversifying their industrial base, or (3) internationalizing the manufacturing base. When firms narrowed their business and geographical scope, however, they reduced university links. We found that building an industry-university relationship was a gradual process. Periods of strategic stability and bidirectional people flows strengthened these relationships. Changes in the firm's CEO, however, signaled modifications in the firm's university relationships. These modifications were contingent on the strategy pursued by the firm and pre-existing industryuniversity systems. Based on those findings, we derive a framework to describe how industry-university relationships evolve with changes in firm strategy. The thesis shows that changes in corporate strategy affect the formation and evolution of university relationships, an idea generalizable to other industries. The strategic change process of forest products firms, however, has features that may be applicable only to large, commodity-grade capital-intensive industries. In particular when confronted by change, forest products firms did not always evolve towards higher positions in the value chain, sometimes moving down this chain divesting internal technological capabilities. These "competency-destroying" cycles tended to coincide with periods of economic downturn. Because of the dissimilarities in the time scale for change, universities can act as "knowledge buffers" for of these cyclical industries, helping firms to regain lost capabilities and allowing corporate technologies time to mature despite changes in firm strategy.
by Julio Alberto Pertuzé Salas.
Ph. D.
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Svensk, Joakim. "Evaluation of Aerial Image Stereo Matching Methods for Forest Variable Estimation". Thesis, Linköpings universitet, Datorseende, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-138166.
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This work investigates the landscape of aerial image stereo matching (AISM) methods suitable for large scale forest variable estimation. AISM methods are an important source of remotely collected information used in modern forestry to keep track of a growing forest's condition. A total of 17 AISM methods are investigated, out of which 4 are evaluated by processing a test data set consisting of three aerial images. The test area is located in southern Sweden, consisting of mainly Norway Spruce and Scots Pine. From the resulting point clouds and height raster images, a total of 30 different metrics of both height and density types are derived. Linear regression is used to fit functions from metrics derived from AISM data to a set of forest variables including tree height (HBW), tree diameter (DBW), basal area, volume. As ground truth, data collected by dense airborne laser scanning is used. Results are presented as RMSE and standard deviation concluded from the linear regression. For tree height, tree diameter, basal area, volume the RMSE ranged from 7.442% to 10.11%, 11.58% to 13.96%, 32.01% to 35.10% and 34.01% to 38.26% respectively. The results concluded that all four tested methods achieved comparable estimation quality although showing small differences among them. Keystone and SURE performed somewhat better while MicMac placed third and Photoscan achieved the less accurate result.
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Lu, Zhenqian. "Development of an integrated forest management decision support system integrating the LANDIS model and ArcGIS /". Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/5059.
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Thesis (M.A.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 10, 2009) Includes bibliographical references.
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Ingemarson, Fredrik. "Small-scale forestry in Sweden : owners' objectives, silvicultural practices and management plans /". Uppsala : Swedish University of Agricultural Sciences, 2004. http://diss-epsilon.slu.se/archive/00000657/.
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Thesis (doctoral)--Swedish University of Agricultural Sciences, 2004.Appendix includes reprints of four papers and manuscripts co-authored with others. Also issued electronically via World Wide Web in PDF format.
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Mala, William Armand. "Knowledge systems and adaptive collaborative management of natural resources in southern Cameroon : decision analysis of agrobiodiversity for forest-agriculture innovations". Thesis, Stellenbosch: University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/1290.
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Thesis (PhD (Dept. of Forest and Wood Science))--University of Stellenbosch, 2009.ENGLISH ABSTRACT: This study aimed to analyze under which conditions the structure, organization and integration of knowledge systems can provide the implementation of adaptive collaborative management of natural resources under conditions of high biodiversity in the humid forest zone of southern Cameroon. The study specifically did the following: characterized sustainable slash-and-burn agriculture innovations; examined the influences of local perceptions of nature and forest knowledge management systems on adaptive slash-and-burn agriculture practices; analyzed the influences of the social representation of land use patterns and their local indicators on agro-ecological sustainability; characterised the biophysical dimensions of local management of agricultural biodiversity knowledge systems; analyzed how local agricultural biodiversity knowledge is used to adapt and to satisfy household consumption needs, market preferences, and sustainable livelihoods; examined the influences of local perceptions of climate variability for the ability and adaptive capacity of people to use local knowledge to deal with the effect of pests-diseases on crop yield, corrective management actions, and adaptive slash-and-burn agriculture management. The study was conducted in three blocks within the humid forest zone of southern Cameroon along a gradient of natural resource use management intensification and population density. Data were collected via structured and semi-structured interviews, multi-disciplinary landscape assessment and a review of secondary information. Chisquare tests were used to show how local knowledge influences - natural resource management at the forest-agriculture interface, while binary logistic regressions were used to understand the influences of biophysical and socio-economic factors on farmers’ decisions to domesticate tree species and to cultivate several crop cultivars. Fourteen research and development (R&D) themes were identified and found to be equally distributed among blocks but unequally distributed across technical, marketing and socio-organisational types of innovation. There was a gap between social demand and innovation offer. Innovations offered covered more technical issues, such as crop variety development, indicating their agricultural focus rather than the integration of forest and agriculture issues. The local perceptions of nature and forest resources are based on social representation of the vital space into components having a specific function for the social, physical and spiritual life of people. Needs of the human world determine the role of local forest knowledge systems in the interpretation and responses of the natural environment, and guide the trajectories of natural resource management practices. The management of agro-ecological sustainability is based on the local definition of well-being, social representation of space and on a multi-criteria approach combining bio-indicators such as plants, earthworm activities, age of vegetation or forest cover, soil colour and quality but it is also positively influenced by land use history, the use value of wild plant and crop species, the knowledge of crop qualities, the knowledge of interactions between crops, and between crops and other wild plant species, the tree size of tree species used, the future use of a current land use, the estimated land use for own use and market access.
AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om te bepaal onder watter omstandighede die struktuur, organisasie en integrasie van kennissisteme kan bydra tot die implementering van aanpasbare deelnemende bestuur van natuurlike hulpbronne onder toestande van hoë biodiversiteit in die vogtige woudsone van suidelike Kameroen. Die studie het spesifiek die volgende gedoen: volhoubare kap-en-brand landboukundige ontwikkelinge gekarakteriseer; die invloede van plaaslike persepsies van die natuur en woudkennisgebaseerde bestuursisteme op aanpasbare kap-en-brand landboupraktyke ge-evalueer; die invloede van die sosiale verteenwoordiging van grondgebruikspatrone en hul plaaslike indikatore op agro-ekologiese volhoubaarheid ontleed; die biofisiese dimensies van die plaaslike bestuur van landboukundige biodiversiteitskennissisteme gekarakteriseer; geanaliseer hoe die plaaslike landboukundige biodiversiteitskennis gebruik word om aan te pas by en bevrediging te verkry vir huishoudelike gebruiksbehoeftes, marksvoorkeure en volhoubare bestaansbehoeftes; die invloede en gebruik van plaaslike kennis en persepsies van klimaatsvariasie beoordeel in die vermoë en aanpassingskapasiteit van mense om die effekte van siektes-peste op gewasproduksie, regstellende aksies en aanpasbare kap-enbrand landboubestuur te hanteer. Die studie is uitgevoer in drie blokke binne die vogtige woudsone van suidelike Kameroen langs ‘n gradient van natuurlike hulpbrongebruiksbestuursintensiteit en populasiedigtheid. Data is versamel deur gestruktureerde en semi-gestruktureerde onderhoude, multi-dissiplinere landskapsevaluering en ‘n oorsig van sekondere inligting. Chi-kwadraat toetse is gebruik om te wys hoe plaaslike kennis die bestuur van die woudlandbou konneksie beinvloed asook binêre logistiese regressies om die invloede te verstaan van biofisiese en sosio-ekonomiese faktore op die boere se besluite om boomsoorte te domestikeer en om verskeie gewaskultivars te kweek. Veertien temas in navorsing en ontwikkeling (N&O) was gelyk versprei tussen die blokke en ongelyk versprei tussen tegniese, bemarking en sosio-organisatoriese tipes innovering. Daar was ‘n gaping tussen sosiale aanvraag en innoveringsaanbieding. Innoverings het meer tegniese aspekte gedek, soos ontwikkeling van ‘n verskeidenheid gewasse, wat wys op ‘n landboukundige fokus eerder as ‘n integrasie van woud en landboukundige aspekte. Die plaaslike persepsies van die natuur en woudhulpbronne was gebaseer op sosiale verteenwoordiging van lewensbelangrike ruimte in komponente met ‘n spesifieke funksie vir die sosiale, fisiese en geestelike lewe van die mense. Behoeftes van die menslike wereld bepaal die rol van plaaslike woudkennissisteme in die interpretasie van en reaksie op die natuurlike omgewing, en rig die gebruik van hulpbronbestuurspraktyke. Die bestuur van agro-ekologiese volhoubaarheid is gebaseer op die plaaslike definisie van geluk, sosiale verteenwoordiging van ruimte en op ‘n multikriteria benadering wat bio-indikatore kombineer soos plante, erdwurmaktiwiteite, ouderdom van plantegroei- of woudbedekking, grondkleur- en kwaliteit, maar is ook positief beinvloed deur grondgebruiksgeskiedenis, die gebruikswaarde van natuurlike en gewassoorte, die kennis van gewaskwaliteite, die kennis van die interaksie tussen gewasse en tussen gewasse en natuurlike plantsoorte, die boomgrootte van boomsoorte wat gebruik word, die toekomstige gebruik van ‘n huidige grondgebruik, die beraamde grondgebruik vir eie gebruik en vir toegang tot die markte.
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Marto, Marco Henrique Vieira. "Innovating forest ecosystems with advanced multi-criteria decision-making methods". Doctoral thesis, ISA, 2020. http://hdl.handle.net/10400.5/21204.
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Doutoramento em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia. Universidade de LisboaThis work focuses on innovating forest ecosystem management planning and on enhancing its contribution to the provision of ecosystem services. A web-based forest decision support system was developed to support public and private forest managers, involving operational research methods. First, all work related to database management and the integration of data was carried out. Databases were created with PostgreSQL, which on the one hand facilitated the development of multi-criteria linear programs, and on the other met all the data and information needs of a forest decision support system, not only for data processing and information presentation, but also as a source to be consulted and analyzed by forest decision makers. The wSADfLOR, a forest web-based decision support system, integrates one analytic tool to visualize interactive decision maps showing the decision space and trade-offs among the criteria in Pareto frontiers, according to forest users’ management options. Taking advantage of constant improvements in the Interactive Decision Maps tool in wSADfLOR, a second article was developed regarding a web-based approach to show interactive decision maps with Pareto frontiers. Based on these interactive decision maps and jointly with some decision support systems available in the EMDS platform (Criterion DecisionPlus and NetWeaver), a hybrid decision methodology for cases in which there is no consensus among the solutions chosen by different (groups of) forest decision makers was developed, enabling them to choose a unique strategic decision plan
N/A
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Weir, Michael John Charlesworth. "Ensuring and maintaining data quality in geographical information systems for forest land management". Thesis, Birkbeck (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325336.
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Robinson, Patrick John. "Role of forestry in farming systems with particular reference to forest-grazing interactions". Thesis, University of Edinburgh, 1985. http://hdl.handle.net/1842/11318.
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Nwachukwu, Chinedu Maureen. "Utilising forest biomass in iron and steel production : investigating supply chain and competition aspects". Licentiate thesis, Luleå tekniska universitet, Energivetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-82997.
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Ndlovu, Nomzamo Bonisiwe. "Quantifying indigenous forest change in Dukuduku from 1960 to 2008 using GIS and remote sensing techniques to support sustainable forest management planning". Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85622.
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Thesis (MSc)--Stellenbosch University, 2013.ENGLISH ABSTRACT: This study aimed to understand how Dukuduku Forest in Kwa-Zulu Natal has changed from 1960 to 2008 and whether the change in political regimes, during and post apartheid eras might have contributed to changes in forest extent. To achieve the aims, the following analyses were made: - Qualitative and quantitative spatial analyses of forest change; - Analyses of the correspondence of change with political changes in the country; - Assessment of perception of people living in the Dukuduku forest area. The Dukuduku land cover was mapped from aerial photos using ArcGIS 9.3 to determine whether or not there has been a significant change in the area from 1960-2008, in response to resource use pressures and to come up with the strategic sustainable management plan from the results found. Five aerial photographs were used to determine the changes in land cover from the year: 1960, 1970, 1992, 2005 and 2008. The Land cover types were classified into four classes, Indigenous Forests, Plantation Forests, Water Bodies and Other (open areas, cultivated land, and all the human disturbed and transformed land). The percentage of cover per class was compared across the years to determine overall change in land cover and the rate of change per year was also calculated. The results from the study showed that: - Natural Forest increased by 11% (700 ha), at the rate of 20.56 hectares per year between 1960 and 1992, which is the apartheid era. Between 1992 and 2008, the democratic era, the forest decreased by 34.4% (2472.31ha), at the rate of 168 hectares per year. - The Dukuduku forest community gains resources (timber and grass for construction, art, firewood, medicinal plants, grazing of livestock and food) from the forest. The people are willing to contribute in protecting the forest only if the governing authorities would include them in decisions made, as the NFA demands Participatory Forest Management, but which does not currently exist in Dukuduku.
AFRIKAANSE OPSOMMING: Hierdie studie ondersoek die verandering van die Dukuduku woud in Kwa-Zulu Natal vanaf 1960 tot 2008, en vernaamlik of die verandering in politieke regimes tydens en in die postapartheid eras tot verandering bygedra het in die woud se vorm. Om hierdie doelwitte te breik is die volgende analises gedoen: - Kwalitatiewe en kwantitatiewe ruimtelike analises van woudverandering; - Analises van die korrelasie tussen hierdie fisiese omgewingsverandering en politieke verandering in die land; - Analise van die persepsie van mense wat in die Dukuduku woudgebied woon. Die Dukuduku gronddekking is gekarteer met behulp van lugfotos, waarvoor ArcGIS 9.3 gebruik is om te bepaal of daar noemenswaardige verandering in die gebied plaasgevind het van 1960 tot 2008, in reaksie op hulpbrongebruike, en om ‘n volhoubare bestuursplan gestel voor wat op die bevindinge gebaseer is. Vyf lugfotos is gebruik om verandering in gronddekking te bepaal vir die jare: 1960, 1970, 1992, 2005 en 2008. Die Gronddekking tipes is geklassifiseer in vier klasse naamlik Inheemse Woude, Plantasiebosse, Waterliggame en Ander (oop gebiede, landerye en al die mens-versteurde en getransfomeerde gebiede). Die persentasie van elke dekkingsklas is oor die jare vergelyk om die verandering in algehele grond-dekking te bepaal, en die tempo van verandering is ook bepaal, asook die tempo van verandering. Die resultate van die studie wys dat: - Die natuurlike woud toegeneem het met 11% (700 ha), teen ‘n tempo van 20.56 hektaar per jaar tussen 1960 en 1992, tgedurende die apartheidsera. Tussen 1992 en 2008, die demokratiese era, het die woude verminder met 34.4% (2472.31 ha), teen ‘n tempo van 168 hektaar per jaar. - Die gemeenskap wat in die Dukuduku woud woon verkry hulpbronne van die woud (hout en gras vir konstruksie, kuns, brandhout, medisinale plante, weiding vir vee, en voedsel). Die mense is gewillig om by te dra tot beskerming van die woud indien die owerhede hulle sou betrek in besluite wat geneem word, veral omdat die nasionale Wet op Bosse voorsiening maak vir Deelnemende Bosbestuur, wat tans nie by Dukuduku gebeur nie.
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Grossinho, Anabela Lopes. "Analysis of damaged Norway spruce stands using Landsat Thematic Mapper and geographic information systems". Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363050.
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Marques, Alexandra Sofia da Fonseca. "New decision support tools for forest tactical and operational planning". Doctoral thesis, ISA/UTL, 2012. http://hdl.handle.net/10400.5/5205.
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Doutoramento em Engenharia Florestal e dos Recursos Florestais - Instituto Superior de AgronomiaThe economic importance of the forest resources and the Portuguese forest-based industries motivated several studies over the last 15 years, particularly on strategic forest planning. This thesis focuses on the forest planning processes at tactical and operational level (FTOP). These problems relate to harvesting, transportation, storing, and delivering the forest products to the mills. Innovative Operation Research methods and Decision Support Systems (DSS) were developed to address some of these problems that are prevalent in Portugal. Specifically, Study I integrates harvest scheduling, pulpwood assortment, and assignment decisions at tactical level. The solution method was based in problem decomposition, combining heuristics and mathematical programming algorithms. Study II presents a solution approach based on Revenue Management principles for the reception of Raw Materials. This operational problem avoids truck congestion during the operation of pulpwood delivery. Study III uses Enterprise Architecture to design a DSS for integrating the operations performed over the pulpwood supply chain. Study IV tests this approach on a toolbox that handled the complexity of the interactions among the agents engaged on forest planning at regional level. Study V proposes an innovative technological framework that combines forest planning with forest operations' control.
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Gunnarsson, Lidestam Helene. "Supply chain optimization in the forest industry". Doctoral thesis, Linköpings universitet, Optimeringslära, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8856.
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The scope of this thesis is modelling and solving large-scale planning problems in the supply chain within the forest industry. Five research papers are included, the first three of which focus on the modelling, and the last two on the solution methods. All problems included are tactical multi-commodity problems expressed as mixed integer programming (MIP) models. The work has been done in collaboration with two Swedish companies within the forest industry. In Paper I, a problem concerning the supply chain of forest fuel for Sydved Energileveranser AB is modelled and solved. We study the problem of deciding when and where forest residues are to be converted into wood chips, and how the residues and chips are to be transported and stored in order to satisfy energy demand at heating plants. The company has long-term contracts with forest owners and saw mills. Decisions in the model include whether or not additional harvest areas and saw mills are to be contracted and which terminals to use. The planning horizon is one year and monthly time periods are used. Papers II--V are based on planning problems at Södra Cell AB. The planning horizon is normally one year. Papers II--III consider only one time period. In Paper II the supply chain from pulp mills to customers is modelled and the combined problem of deciding terminal locations and which ship routes to use is studied. Shipping vessels chartered on short or long term are used to transport products to terminals in Europe. From each terminal, the products are transported to customers by truck, train, or a combination of both. In addition, trains and trucks can be used for transports directly to customers from mills. In Paper III the entire supply chain, from harvest areas to customers, is considered. Decisions included are transportation of raw materials, production mix, the distribution of pulp products, and the selection of potential orders and their quantities at customers. The ship routes are considered as flow links. In Papers IV--V the problems in Papers II--III are combined into one model and several time periods are used. Lagrangian heuristics based on Lagrangian decomposition are used as solution methods in both papers. In Paper IV, the approach leads to subproblems for each time period, whereas in Paper V, another approach that results in subproblems for different parts of the supply chain is developed. All models are based on real data from the companies. The models are detailed and describe the problems accurately. The solution methods are developed such that the solution time is kept within practical limits. Results from Papers II--III have been used by Södra Cell AB to support the change of the terminal structure as well as in budget planning.Denna avhandling presenterar matematiska modeller och lösningsmetoder för optimering av olika logistikproblem inom skogsindustrin. Vi studerar försörjningskedjor för skogsbränsle och massaproduker, och beaktar den årliga planeringen i syfte att optimera flödet. Det första problemet behandlar skogsbränsle och är ett samarbete med Sydved Energileveranser AB. Råmaterial i form av grenar och toppar från avverkningsplatser ska flisas och transporteras till värmeverk, eventuellt via terminaler. Det finns möjlighet att flisa både i skogen och på terminaler. Biprodukter från sågverk kan också användas som råmaterial. Vid behov kan utbudet av råmaterial utökas genom att fler avverkningsplatser och sågverk kontrakteras. Värmeverken har en efterfrågan, angiven i kWh per månad, som ska uppfyllas. Exempel på beslut som ska tas är var flisning ska ske, om nya avverkningsplatser ska kontrakteras, var lagring ska ske, samt hur och när skogsbränslet ska transporteras. Nästföljande problem behandlar massaprodukter och är ett samarbete med Södra Cell AB. Olika sorters massaved från skogen och biprodukter från sågverk utgör råmaterial för produktion av massaprodukter. Råmaterialet transporteras till massabruk för tillverkning enligt specificerade recept. De färdiga produkterna transporteras sedan med fartyg till terminaler i Europa. Från terminalerna transporteras produkterna vidare till pappersbruk, vilka är företagets slutkunder. Massaprodukterna transporteras i vissa fall med lastbil eller tåg direkt från massabruken till kunderna. Efterfrågan är angiven inom vissa gränser i olika order. Vissa order är fasta, vilket innebär att dess efterfrågan måste uppfyllas, medan andra order är fria. Exempel på beslut som ska tas är vilka bruk olika produkter ska produceras på, hur många och vilka terminaler som ska användas, samt hur transporterna ska utföras för att ge bästa resultat. Utifrån ovanstående beskrivningar har matematiska modeller formulerats. Ge-nom att lösa dessa kan vi få svar på logistik- och transportfrågorna och ett optimalt flöde kan hittas. För att lösa modellerna har kommersiell programvara använts. Heuristiker och mer avancerade optimeringsmetoder har också utvecklats i syfte att producera bra lösningar snabbare.
Article 4 was a manuscript entitled "Solving a multi-period supply chain problem for a pulp industry using Lagrangian heuristics based on time periods" at the time of the thesis defence.
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Asritha, Kotha Sri Lakshmi Kamakshi. "Comparing Random forest and Kriging Methods for Surrogate Modeling". Thesis, Blekinge Tekniska Högskola, Fakulteten för datavetenskaper, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-20230.
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The issue with conducting real experiments in design engineering is the cost factor to find an optimal design that fulfills all design requirements and constraints. An alternate method of a real experiment that is performed by engineers is computer-aided design modeling and computer-simulated experiments. These simulations are conducted to understand functional behavior and to predict possible failure modes in design concepts. However, these simulations may take minutes, hours, days to finish. In order to reduce the time consumption and simulations required for design space exploration, surrogate modeling is used. \par Replacing the original system is the motive of surrogate modeling by finding an approximation function of simulations that is quickly computed. The process of surrogate model generation includes sample selection, model generation, and model evaluation. Using surrogate models in design engineering can help reduce design cycle times and cost by enabling rapid analysis of alternative designs.\par Selecting a suitable surrogate modeling method for a given function with specific requirements is possible by comparing different surrogate modeling methods. These methods can be compared using different application problems and evaluation metrics. In this thesis, we are comparing the random forest model and kriging model based on prediction accuracy. The comparison is performed using mathematical test functions. This thesis conducted quantitative experiments to investigate the performance of methods. After experimental analysis, it is found that the kriging models have higher accuracy compared to random forests. Furthermore, the random forest models have less execution time compared to kriging for studied mathematical test problems.
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Bernard, Aaron Michael. "Geospatial Modeling of Forest Road Networks and Their Effect on Stream Macroinvertebrate Communities". Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/33338.
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Road construction and maintenance throughout the country continues to be one of the largest contributors of sediment pollution to aquatic systems. Though impacts of road networks on aquatic systems can be potentially severe, little work has been performed to evaluate the effect that road spatial location within a watershed has on water quality. To address this issue from a quantitative perspective, a â Road Impact Factorâ protocol was designed to identify potential erosion-prone segments of road networks based on road gradient, spatial location based on hydrologic flow length, surface composition, and water control installations. The protocol was developed for two regions in Central Idaho and Eastern Oregon. We then used the hydrologic travel time procedure, developed for use in the Hydrologic Engineering Center Hydrologic Modeling System (HEC-HMS) runoff and routing model, in order to characterize the spatial distribution of potential road runoff impacts within the study areas. Ten macroinvertebrate metrics sensitive to sedimentation (i.e. % Intolerant Taxa, Hilsenhoff Biotic Index, etc.) were analyzed to test the significance of the spatial distribution of Road Impact Factors. These 10 metrics were analyzed under the hypothesis that values will be lower for those study areas that have a higher degree of road impact and a lower distance between the road segments and stream reaches. Results of a quadrant analysis and hierarchical clustering analysis showed hypothesized trends for several metrics in Idaho, though the trends were not strong. No trends were observed in Oregon. The variability in results is likely due to limitations of the input datasets.Master of Science
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Kmon, Megan Kathleen. "Systems Thinking in the Forest Service: a Framework to Guide Practical Application for Social-Ecological Management in the Enterprise Program". PDXScholar, 2016. http://pdxscholar.library.pdx.edu/open_access_etds/3312.
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The U.S. Forest Service (USFS) Enterprise Program (EP), which provides fee-for-service consulting services to the USFS, is interested in integrating systems thinking into its service offerings. Despite there being several excellent sources on the range and diversity of systems thinking, no single framework exists that thoroughly yet concisely outlines what systems thinking is along with its deep history, theoretical tenets, and soft and hard approaches. This thesis is an attempt to create such a framework, aimed specifically at practical application in a land management agency, through literature synthesis injected with original analysis. The usefulness of the framework is then tested using three case studies within the EP and the agency as a whole.
The framework highlights several important aspects of systems thinking, both generally and related specifically to social-ecological management. First, systems thinking is the transdisciplinary study of complex phenomena from a holistic, rather than reductionist, perspective. The world can be viewed as a massive set of embedded systems -- elements with relations that lead to nonlinear behavior -- making the role of the observer essential in identifying scales of interest and interactions amongst them. Second, the deep history of holistic thinking suggests that its modern scientific study could benefit from exploring the East's long-standing cultural and spiritual approaches to holism through cognitive unity and oneness with mankind and nature. Third, categorizations of systems approaches as "soft" versus "hard" are helpful but can distract us from the ultimate goal of systems thinking, which is to understand the various tools in the systems thinking toolbox so as to apply them critically and creatively to make a meaningful difference in the world. Fourth, I see the soft systems approaches as having a distinct systems thinking orientation and the hard systems approaches as overlapping substantially with operations research, the close cousin of systems thinking. Fifth, I identify a spectrum of complexity, contending that systems thinking tends to be concerned with what I call subjectively and computationally complex systems, as well as complex adaptive systems, leaving simple systems for other approaches. Finally, I contend that it is the soft systems approaches and the two theoretical pillars of hierarchy theory and cooperation theory that will aid wicked social-ecological problem solving the most.
The framework is applied to three case studies. Examination of the EP reorganization using a hard systems approach revealed two critical high-level functions that were absent in the current structure, paving the way for new designs that could take those functions into account. Analysis of an initiative to increase citizen recreation on USFS lands showed that a systems approach had been improperly applied and how the application of a soft approach at the onset could have systematically framed the problem and offered unique normative insights for giving voice to relevant non-agency stakeholders as well as nature and future generations. And viewing the perennial problem of wildfire management through the lens of cooperation theory revealed how USFS leadership could take a more active role in promoting the long-term outlook, durable relationships, and reciprocal behaviors that are required for cooperative improvement to take place.
As environmental narratives worsen and the need for transitioning towards sustainable ways of living heightens, systems thinking offers ever-increasing value to resource managers for its ability to deal with the many perspectives and normative content that underlie wicked problems and to help to illuminate potential consequences of system interventions given the interplay of complex structural dynamics across space and time.
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Agarwal, Jutshi. "Application of Fuzzy Logic for Enhanced Situational Awareness of Surface Wildfires". University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1511856508378518.
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Plugge, Daniel [Verfasser] y Michael [Akademischer Betreuer] Köhl. "Capabilities and deficiencies of terrestrial forest inventory systems in the assessment of forest degradation in the scope of REDD+ / Daniel Plugge. Betreuer: Michael Köhl". Hamburg : Staats- und Universitätsbibliothek Hamburg, 2013. http://d-nb.info/1030366136/34.
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Bostock, Alison Claire. "Chemical speciation, volatilisation and cycling of 36I, 129I and 99Tc in coniferous forest systems". Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412564.
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Gitas, Ioannis. "Geographical information systems and remote sensing in mapping and monitoring fire-altered forest landscapes". Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621715.
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Ngulube, Elisha Stephen. "Prediction of timber harvesting productivity for semi-mechanised systems in Viphya forest plantations, Malawi". Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/30939.
Texto completoResumen
At least 200,000 m3 of timber are harvested annually using semi-mechanised harvesting
systems (SMS) on the Viphya forest plantations in Malawi. Although these systems have
long been used on the Viphya, no investigation on their productivity has so far been reported.
The absence of local productivity models created uncertainty about the importance of sitebased
factors that influence timber harvesting productivity of these systems on the Viphya.
Secondly, there is paucity of information regarding the appropriate timber harvesting systems
for production maximisation and cost minimisation. This study aimed to develop prediction
models for estimating the productivity and costs of semi-mechanised and simulated
mechanised timber harvesting systems on the Viphya forest plantations.
The study was conducted in Pinus kesiya stands at Kalungulu and Champhoyo forest stations
of the Viphya forest plantations. A work study approach was followed to capture harvesting
time and volume data. Stepwise multiple regressions were used to develop felling time
models for a chainsaw over tree size, inter-tree distance, slope, ground condition, brush
density, and ground roughness; and skidding time models over distance, slope, ground
condition, ground roughness and volume skidded per cycle for a grapple skidder. Models
were statistically validated. Secondary work study data for semi-mechanised systems were
simulated for mechanised productivity based on local site factors.
The study had shown that diameter at breast height and inter-tree distance were important
factors that best explained felling time prediction models in Pinus kesiya stands on the
Viphya forest plantations. Similarly, distance from stump to the roadside landing was the
most important factor in addition to volume load, slope and ground conditions that
determined grapple skidding time.
Mechanised systems appear to be more advantageous than semi-mechanised systems. The
former are associated with lower operating costs and inventories with relatively high
production rates. Therefore, mechanised systems could help to optimise timber harvesting
productivity on the Viphya. Further studies should be conducted to determine the effect of
different ground conditions and roughness on skidding productivity.Dissertation (MSc)--University of Pretoria, 2012.
Plant Production and Soil Science
MSc
Unrestricted