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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.
81

Apply Fuzzy Cluster Method for Identifying the Spatial Distribution of Pollutants around Kaohsiung Coastal Water

Chang, Dun-Cheng 15 August 2002 (has links)
Abstract The near shore water intake pollutants from the land area and is heavily polluted. In order to assess such impact efficiently, the focus of marine environmental monitoring is shifting from inspecting pollutants in a water body to the measurement of pollutants adhered to sediments on seabed. The statistical methods are then used to analyze survey data for the purpose of interpretation. As for the problem of identifying the spatial distributions of classified pollutants over the water around Kaohsiung harbor, the result from the commonly used K-Means Cluster Analysis is not very satisfactory. It is therefore that the proposed research is trying to use the Fuzzy Cluster Method (FCM) to achieve better results. Through adaptive searching approach, the FCM should be able to generate the appropriate cluster centers for discerning the pollutants¡¦ spatial distribution, which in turn would convey more meaning to support feasible interpretation. The FCM model developed by this research will also help to trace the most suspicious or new pollutant source with the assistance from the domain expertise if an unusual pollutant were found in the study area. The benefit is therefore obvious that the authority in charge of marine environment can respond efficiently and correctly against such pollution event and take appropriate actions. FCM has been heavily applied to the research on computer vision and pattern recognition with great success. Recently quite amounts of literatures in the environmental and natural resource management study, including geo-statistical modeling, pollution mitigation, and groundwater quality management, have probed into the applications of cluster analysis using FCM. The problems of marine environment are highly complex and full of uncertainty in nature. Nevertheless by introducing advanced analysis techniques, such as FCM, for tackling such problems, the overall managerial efficiency of marine environment will be improved.
82

Seasonal Variations in Fish Assemblages of Small Warmwater Streams in Four Southeastern National Parks

Zimmerman, Joseph Carl 01 May 2007 (has links)
Small warm-water streams in the southeastern United States experience significant differences in temperature, as well as changes in physical parameters due to seasonal fluctuations. It has been generally thought that fish assemblage patterns change as a direct result of these seasonal variations. This study was designed to determine the effects of variable flow regimes on fish species composition, diversity, and abundance. Eight small warm-water streams in four national parks (Chickamauga and Chattanooga National Military Park, Fort Donelson National Battlefield, Abraham Lincoln Birthplace National Historic Site, and Russell Cave National Monument) were sampled May-June 2005 for the summer trials, October-November 2005 for the fall trials, and April 2006 for the spring trials. All trials were conducted when water levels and flows were at normal seasonal stages. Fish populations were determined by electrofishing a 100-m reach at each site. Physical parameters including temperature, dissolved oxygen, conductivity, pH, and flow rate were also measured at each site. From summer to fall, the majority of the streams decreased in flow until temporary pools were formed. The lack of flow caused increased temperatures, decreased dissolved oxygen, and increased conductivity levels. As a direct result, overall fish abundance and diversity values decreased. From fall to spring, all the streams increased in flow, which brought back the riffle to pool habitat sequences. Dissolved oxygen levels increased, conductivity levels decreased, and temperatures became more stable. As a result, overall fish abundance and diversity values increased. Results indicated that fish assemblage patterns in the four parks did change as a direct result of the seasonal variations in habitat and water quality.
83

Growth and suitability of some tree species selected for planting in adverse environments in Eritrea and Ethiopia /

Mehari, Amanuel, January 2005 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv. / Härtill 5 uppsatser.
84

Use of light intensity, temperature, and humidity to verify exposure location.

Stanch, Penney. Stock, Thomas H. January 2007 (has links)
Source: Masters Abstracts International, Volume: 45-06, page: 3140. Adviser: Thomas Stock. Includes bibliographical references.
85

Microenvironmental air and soil monitoring of contaminants an evaluation of indoor and outdoor levels in Chihuahua City /

Delgado-Rios, Marcos, January 2007 (has links)
Thesis (Ph. D.)--University of Texas at El Paso, 2007. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
86

Development and validation of the marine benthic copepod Robertsonia propinqua as a bioindicator to monitor estuarine environmental health : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at Lincoln University, New Zealand /

Hack, Lisa Adelheid. January 2008 (has links)
Thesis (Ph. D.) -- Lincoln University, 2008. / Also available via the World Wide Web.
87

Gill EROD activity in fish : a biomarker for waterborne Ah-receptor agonists /

Abrahamson, Alexandra, January 2007 (has links)
Diss. (sammanfattning) Uppsala : Uppsala Universitet, 2007. / Härtill 5 uppsatser.
88

Using multispectral sensor WASP-LITE to analyze harmful algal blooms /

McNamara, Shari J. January 2007 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2007. / Typescript. Includes bibliographical references (leaves 133-138).
89

Near-optimal node clustering in wireless sensor networks for environment monitoring /

Xia, Dawei. January 2006 (has links)
Thesis (M.Sc.)--York University, 2006. Graduate Programme in Computer Science. / Typescript. Includes bibliographical references (leaves 97-100). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR19758
90

Freshwater tortoises Chelodina Longicollis Shaw and Emydura SP (Cooper Creek) : their potential as bio-monitors of environmental heavy metal contamination /

Staples, Peter G. January 1992 (has links) (PDF)
Thesis (B. Sc.(Hons.))--University of Adelaide, Department of Environmental Science and Rangeland Management, 1992. / Includes bibliographical references (leaves 28-29).

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