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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.
101

Human Induced Cyclical Erosion Due to Altered Sediment Bypassing Mechanisms of a Barrier Island and the Resultant Impact on the Housing Market

Fallon, Andrew R. 01 January 2015 (has links)
No description available.
102

Use of a Landscape-Level Approach to Determine the Habitat Requirements of the Yellow-Crowned Night-Heron, Nycticorax violaceus, in the Lower Chesapeake Bay

Bentley, Ellen L. 01 January 1994 (has links)
No description available.
103

A Study of the Exotic Game Bird Introduction Program in the Sandy Point Area of Virginia 1970-1971

Wachtmeister, Hans 01 January 1971 (has links)
No description available.
104

Population Dynamics of Ospreys in Tidewater Virginia

Kennedy, Robert Senior 01 January 1971 (has links)
No description available.
105

Theorising information use : managers and their work

Kirk, Joyce, 1945- January 2002 (has links)
No description available.
106

Theorising information use: managers and their work

January 2002 (has links)
The focus of this thesis is information use. Although a key concept in information behaviour, information use has received little attention from information science researchers. Studies of other key concepts such as information need and informationseeking are dominant in information behaviour research. Information use is an area of interest to information professionals who rely on research outcomes to shape their practice. There are few empirical studies of how people actually use information that might guide and refine the development of information systems, products and services. The thesis begins to address this imbalance in information behaviour research by exploring the concept of information use through an empirical study. Fifteen senior managers from two organisations in the cultural industries sector participated in the study. Analysis of interviews revealed that the managers understood and experienced information use in five different ways: as information packaging; as information flow; as developing new knowledge and insights; as shaping judgements and decisions; and as influencing others. These five different ways of experiencing information use are related in a hierarchy that reflects three different views of information: as an object; as a construct; and as a transformative force. Embedded in the hierarchy are different relations between people and information in their work environments, different processes of information use and different criteria for determining the quality of information that is used. The thesis demonstrates that the concept of information use can be explored empirically using phenomenography as the research approach. This approach, which originated in the field of education, has been used infrequently in information behaviour research. It offers potential for the further exploration of not only information use but also other concepts germane to information behaviour. The thesis highlights the richness of peoples' experiences of information use and points to some directions that might be taken by practitioners in developing information systems, products and services to support people as they 'go about their business'.
107

A Team-Based Approach to Social Learning Research in Natural Resource Management

Fogel, Jonah Malachai 01 August 2007 (has links)
This thesis responds to the need to quantify social learning and its outcomes as it relates to natural resource management. Social learning enables individuals engaging in collective action to understand each other’s perspectives, encourages integration of diverse knowledge bases, and the creation of new knowledge (Keen, Brown, & Dyball, 2005). However, the concept currently lacks a clear operational definition in natural resource management. The lack of an operational definition for social learning has stymied attempts to validate its espoused ability to improve civic discourse and, ultimately, resource governance (Pahl-Wostl & Hare, 2004). This report is composed of three papers that collectively offer a way forward for this area of research. The first paper supplies an operational definition of social learning based on team cognition research in organizational psychology. One possible research framework for the assessment of social learning is provided. The second paper presents a case study using this framework. The case study takes place within the context of private forestlands management; a growing arena for collective action institutions. A pre-test and post-test quasi-experimental design is used to test for social learning resulting from a participatory research intervention. The third paper documents the results of the participatory research intervention, independent of the social learning framework.
108

Ore forming potential of the Atchiza Suite and Sustainable management of mineral deposits in Mozambique : "Petrology, geochemistry and sustainable management of mineral deposits"

John, Kangeze Biteme January 2012 (has links)
Part 1- Abstract This research study presents detailed petrographic- and geochemical- analysis of 63 rock samples from the Atchiza Suite. The Suite is a layered mafic-ultramafic pluton located in the Tete Suite, of NW Mozambique. At present, the Atchiza comprises a group of three main types of rock that are classified based on their mineralogy, textures, geochemical composition. These are ultramafic cumulates (dunite and pyroxenites), mafic cumulates (medium-grained cumulate gabbro) and coarse-grained gabbro (non-cumulate gabbro). Compared to the rest of other rocks, coarse-grained gabbro shows high enrichment of Ti (0.64-3.46 wt% TiO2), Zr (5.9-296.1 5ppm), Sr (253.7-1268.4ppm) and V (224-952.3ppm), but relatively low depleted in compatible elements (Ni = 48.7-235.7ppm , Cr = below detection limit to 410.5ppm). Cumulate ultramafics are highly enriched in compatible elements (Ni up to 4636.2ppm, Cr up to 4721ppm). A high Mg# in ultramafic cumulates (0.59-0.86) suggests an Mg-rich primitive parental magma, whereas a low Mg# in coarse-grained gabbro (0.23-0.37) suggests a relatively high-differentiated magma. Cumulate gabbro shows Mg# ranging from 0.40-0.72, suggesting a moderately evolved magma source (derivative magma subsequent to fractionation of ultramafic cumulates). The Ni/Zr, Cr/Zr, Sr/Zr and Ti/Zr ratios are generally the lowest in coarse-grained gabbro when compared to cumulate rocks. The same applied; this suggests that coarse-grained gabbros were probably formed from a relatively high-differentiated magmatic liquid. In addition, the presence of an uninterrupted cryptic differentiation trend with these ratios implies that the Atchiza igneous lithologies were derived from one and the same parental melt. Apparently, Atchiza shows great variability of Fe2O3, SiO2 and SO3 during magmatic differentiation. There is significant decrease in Fe2O3, an increased SiO2 and SO3 contents in residual magma during progressive magma fractionation. It is true that all these geochemical changes will lower down the solubility of S in the system, thus providing a favourable condition for silicate-sulfide immiscibility. Theoretically, therefore, the Atchiza may have a potential to host Ni-Cu-(PGE) sulfide deposits. Part 2- Abstract Unlike water and forests, minerals are finite resources; they cannot be replaced back to their natural forms once they are depleted. For that reason, sustainable management of mineral resources is very important so that stakeholders in the extractive sector are guaranteed the same opportunities in sharing benefits. As part of this study, and with respect to Atchiza Suite, this section is discussing sustainable management of mineral deposits in Mozambique. Investment in Mozambican extractive industry should primarily be done with the main objective of poverty reduction for Mozambican citizens. Thus, the Mozambican Government needs to realize that proper management of mineral deposits will provide sufficient income for the country, enough to fund other development projects. Rather than being mismanaged, this massive collection of mineral revenues needs to be appropriately re-invested back to diversify other economic sectors. If this mineral revenue is managed wisely, the national annual budgets will be sufficiently supported. Most importantly, the country’s reliance on international loans and aids will be reduced significantly. Decision-making for development of the country’s mineral projects should not be central-governed; rather it should be transparent to the public and open for opinions and suggestions. As the main stakeholder in Mozambican extractive sector, local communities and civil societal groups should also be given opportunities to participate in decision-making, important for the development of mining projects. Mineral agreements for which the Mozambican State has been signing with multinational companies for development of the country’s mineral projects need to be published and be available publicly. In addition, negotiation of mining agreements must be transparent and involve all stakeholders. Investment and development of the country’s mineral projects must be performed through partnerships and Joint ventures between multinational mining companies, national-based companies and the Mozambican State. Development of mineral deposits must incorporate environmental sustainability. Despite its high mineral potential (e.g. Ni-Cu-PGE-Ti-V), Atchiza also is surrounded by a wide range of other natural resources. The Cahora Bassa Dam, which is located just adjacent to Atchiza Project, is the main source of clean energy not only for Mozambique domestic market, but also for the majority of Sub-Saharan countries. All of these natural resources require good practice of Environmental sustainability in mining activities.
109

Texas Water Resources: Vulnerability from Contaminants

Dwivedi, Dipankar 14 March 2013 (has links)
Numerical models of flow and transport are commonly applied for the sustainable management of water resources and for the selection of appropriate remediation techniques. However, these numerical models are not always accurate due to uncertain parameters and the disparity of scales across which observations are made, hydrological processes occur, and modeling is conducted. The modeling framework becomes further complex because hydrologic processes are coupled with chemical and biological processes. This dissertation focuses on the most widespread contaminants of surface and ground water, which are E. coli and nitrate, respectively. Therefore, this research investigates the linkages between bio-chemical and hydrologic processes for E. coli transport, explores the spatio-temporal variability of nitrate, quantifies uncertainty, and develops models for both E. coli and nitrate transport that better characterize these biogeochemical linkages. A probabilistic framework in the form of Bayesian Neural Networks (BNN) was used to estimate E. coli loads in surface streams and was compared with a conventional model LOADEST. This probabilistic framework is crucial when water quality data are scarce, and most models require a large number of mechanistic parameters to estimate E. coli concentrations. Results indicate that BNN provides better characterization of E. coli at higher loadings. Results also provide the physical, chemical, and biological factors that are critical in the estimation of E. coli concentrations in Plum Creek, Texas. To explore model parameters that control the transport of E. coli in the groundwater (GW) and surface water systems, research was conducted in Lake Granbury, Texas. Results highlight the importance of flow regimes and seasonal variability on E. coli transport. To explore the spatio-temporal variability of nitrate across the Trinity and Ogallala aquifers in Texas, an entropy-based method and a numerical study were employed. Results indicate that the overall mean nitrate-N has declined from 1940 to 2008 in the Trinity Aquifer as opposed to an increase in the Ogallala Aquifer. The numerical study results demonstrate the effect of different factors like GW pumping, flow parameters, hydrogeology of the site at multiple spatial scales. To quantify the uncertainty of nitrate transport in GW, an ensemble Kalman filter was used in combination with the MODFLOW-MT3DMS models. Results indicate that the EnKF notably improves the estimation of nitrate-N concentrations in GW. A conceptual modeling framework with deterministic physical processes and stochastic bio-chemical processes was devised to independently model E. coli and nitrate transport in the subsurface. Results indicate that model structural uncertainty provides useful insights to modeling E. coli and nitrate transport.
110

Why Do Some Areas Have Higher Density of Forest Grouse Than Others?

Kvistad, Arne Ivar January 2011 (has links)
Landscape and vegetation data were extracted from digital maps by use of GIS. These data together with predator and management related data collected from landowners and hunter's associations in Norway, were used as explanatory parameters in an analysis of density estimates of black grouse and capercaillie in a number of study sites in Norway. By habitat modeling the dominating wood type and the landscape heterogeneity of an area were identified as important factors affecting the black grouse populations. For the capercaillie the forest cover, proportion of blueberry forest and abundance of pine marten were appointed to be important factors.

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