Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Naval Architecture and Marine Engineering, 1916. / by T. S. Chu, C. Wang. / M.S.

Thesis (M.S.) Massachusetts Institute of Technology. Dept. of Naval Architecture and Marine Engineering, 1946. / Bibliography: leaves 243-244. / by Hector McVey. / M.S.

Aerosol production from surface waters results in the transfer of aquatic materials (including nutrients and bacteria) to air. These materials can then be transported by onshore winds to land, representing a biogeochemical connection between aquatic and terrestrial systems not normally considered. In urban waterfront environments, this transfer could result in emissions of pathogenic bacteria from contaminated waters. Despite the potential importance of this link, sources, near-shore deposition, identity and viability of microbial aerosols are largely uncharacterized. This dissertation focuses on the environmental and biological mechanisms that define this water-air connection, as a means to build our understanding of the biogeochemical, biogeographical, and public health implications of the transfer of surface water materials to the near-shore environment in both urban and non-urban environments. The effects of tidal height, wind speed and fog on coastal aerosols and microbial content were first quantified on a non-urban coast of Maine, USA. Culture-based, culture-independent, and molecular methods were used to simultaneously sample microbial aerosols while monitoring meteorological parameters. Aerosols at this site displayed clear marine influence and high concentrations of ecologically-relevant nutrients. Coarse aerosol concentrations significantly increased with tidal height, onshore wind speed, and fog presence. Tidal height and fog presence did not significantly influence total microbial aerosol concentrations, but did have a significant effect on culturable microbial aerosol fallout. Molecular analyses of the microbes settling out of near-shore aerosols provided further evidence of local ocean to terrestrial transport of microbes. Aerosol and surface ocean bacterial communities shared species and in general were dominated by organisms previously sampled in marine environments. Fog presence strengthened the microbial connection between water and land through air by increasing microbial aerosol settling rates and enhancing viability of aerosolized marine microbes. Using methods developed for the non-urban site, the role of local environment and winds in mediating water-air connections was further investigated in the urban environment. The local environment, including water surfaces, was an important source of microbial aerosols at urban sites. Large portions of the urban waterfront microbial aerosol communities were aquatic and, at a highly polluted Superfund waterfront, were closely related to bacteria previously described in environments contaminated with hydrocarbons, heavy metals, sewage and other industrial waste. Culturable urban aerosols and surface waters contained bacterial genera known to include human pathogens and asthma agents. High onshore winds strengthened this water-air connection by playing both a transport and production role. The microbial connection between water and air quality outlined by this dissertation highlights the need for information on the mechanisms that deliver surface water materials to terrestrial systems on a much larger scale. Moving from point measurements to landscape-level analyses will allow for the quantitative assessment of implications for this microbial water-air-land transfer in both urban and non-urban arenas.

by Kwok Yuk Chun. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 105-124). / Text in English; abstracts in English and Chinese. / by Kwok Yuk Chun. / Acknowledgements --- p.i / Abstract --- p.ii / Contents --- p.vi / List of Figures --- p.x / List of Tables --- p.xiii / List of Plates --- p.xiv / List of Appendices --- p.xv / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1 --- Hong Kong --- p.1 / Chapter 1.2 --- Sediment --- p.1 / Chapter 1.3 --- Pore water --- p.5 / Chapter 1.4 --- Toxicity identification evaluation (TIE) --- p.10 / Chapter 1.4.1 --- Phase 1: Toxicity characterization --- p.11 / Chapter 1.4.2 --- Phase 2: Toxicity identification --- p.11 / Chapter 1.4.3 --- Phase 3: Toxicity confirmation --- p.13 / Chapter 1.5 --- Bioassay --- p.15 / Chapter 1.6 --- Microtox® test --- p.16 / Chapter 2. --- OBJECTIVES --- p.18 / Chapter 3. --- MATERIALS AND METHODS --- p.19 / Chapter 3.1 --- Source of sediment samples --- p.19 / Chapter 3.2 --- Preparation of pore water --- p.19 / Chapter 3.3 --- Phase 1 Toxicity characterization: Baseline toxicity test --- p.22 / Chapter 3.3.1 --- Microtox® test --- p.22 / Chapter 3.3.2 --- Phase 1 Toxicity characterization --- p.26 / Chapter 3.3.3 --- pH adjustment test --- p.27 / Chapter 3.3.4 --- pH adjustment filtration test --- p.28 / Chapter 3.3.5 --- pH adjustment aeration test --- p.29 / Chapter 3.3.6 --- pH adjustment C18 solid phase extraction (SPE) test --- p.30 / Chapter 3.3.7 --- Cation exchange test --- p.32 / Chapter 3.3.8 --- Anion exchange test --- p.33 / Chapter 3.4 --- Phase 2 Toxicity identification --- p.34 / Chapter 3.4.1 --- Determination of metal ions by inductively coupled plasma emission spectroscopy (ICP-ES) --- p.35 / Chapter 3.4.2 --- Determination of anions by ion chromatography (IC) --- p.36 / Chapter 3.4.3 --- Determination of organic compounds by a total organic carbon (TOC) --- p.36 / Chapter 3.4.4 --- Determination of organic compounds by gas chromatography-mass spectroscopy (GC-MS) --- p.37 / Chapter 3.4.5 --- Determination of organic compounds by liquid chromatography-mass spectroscopy (LC-MS) --- p.38 / Chapter 3.4.6 --- Determination of sulphide by colorimetric method --- p.41 / Chapter 3.5 --- Phase 3 Toxicity confirmation --- p.41 / Chapter 3.5.1 --- Mass balance test --- p.44 / Chapter 3.5.2 --- Spiking test --- p.44 / Chapter 4. --- RESULTS --- p.45 / Chapter 4.1 --- General characteristics of the sediment collected in Kwun Tong Typhoon Shelter --- p.45 / Chapter 4.2 --- General characteristics of the pore water after the centrifugation of sediment --- p.45 / Chapter 4.3 --- Phase 1-Toxicity characterization: Baseline toxicity test --- p.45 / Chapter 4.4 --- Phase 1-Toxicity characterization --- p.48 / Chapter 4.4.1 --- Effect of manipulations on Sample S1 --- p.48 / Chapter 4.4.2 --- Effect of manipulations on Sample S2 --- p.50 / Chapter 4.4.3 --- Effect of manipulations on Sample S3 --- p.50 / Chapter 4.4.4 --- Effect of manipulations on Sample S4 --- p.52 / Chapter 4.4.5 --- Effect of manipulations on Sample S5 --- p.55 / Chapter 4.4.6 --- Effect of manipulations on Sample S6 --- p.57 / Chapter 4.4.7 --- Summary of the Phase 1 manipulations on the Microtox® test --- p.59 / Chapter 4.5 --- Phase 2-Toxicity identification --- p.59 / Chapter 4.5.1 --- Summary of the Phase 2 toxicity identification --- p.70 / Chapter 4.6 --- Phase 3-Toxicity confirmation --- p.70 / Chapter 4.6.1 --- Result of Phase 3 for Sample S3 --- p.70 / Chapter 4.6.2 --- Result of Phase 3 for Sample S4 --- p.73 / Chapter 4.6.3 --- Result of Phase 3 for Sample S5 --- p.76 / Chapter 4.6.4 --- Result of Phase 3 for Sample S6 --- p.79 / Chapter 4.6.5 --- Summary of the Phase 3 toxicity confirmation --- p.79 / Chapter 5. --- DISCUSSION --- p.82 / Chapter 5.1 --- Phase 1 Toxicity characterization: Baseline toxicity test --- p.82 / Chapter 5.1.1 --- Baseline toxicity of whole pore water samples on the Microtox® test --- p.82 / Chapter 5.2 --- Phase 1-Toxicity characterization: Manipulations --- p.83 / Chapter 5.2.1 --- Effect of manipulations on the Microtox® test --- p.83 / Chapter 5.2.2 --- pH adjustment test --- p.83 / Chapter 5.2.3 --- pH adjustment filtration test --- p.84 / Chapter 5.2.4 --- pH adjustment aeration test --- p.85 / Chapter 5.2.5 --- Cation exchange test --- p.85 / Chapter 5.2.6 --- Anion exchange test --- p.86 / Chapter 5.2.7 --- pH adjustment C18 solid phase extraction (SPE) test --- p.86 / Chapter 5.3 --- Phase 2-Toxicity identification --- p.87 / Chapter 5.4 --- Phase 3-Toxicity confirmation --- p.88 / Chapter 5.4.1 --- Mass balance on the Microtox® test --- p.89 / Chapter 5.4.2 --- Spiking test on the Microtox® test --- p.90 / Chapter 5.5 --- Explanation of S as the major toxicant in Phase 1，Phase 2 and Phase3 --- p.90 / Chapter 5.6 --- Characteristics of Sulphide (S2-) --- p.91 / Chapter 5.6.1 --- Sources of S2- --- p.91 / Chapter 5.6.2 --- Harmful effect of S “ and its toxicity --- p.93 / Chapter 5.6.3 --- Sulphide determination by colorimetric method --- p.94 / Chapter 5.6.4 --- Sulphide determination by other methods --- p.95 / Chapter 5.6.5 --- Sulphide preservation --- p.95 / Chapter 5.7 --- Synergistic effect of S2- and C18 SPE test elutriate --- p.96 / Chapter 5.8 --- Treatment of contaminated marine sediment in Hong Kong --- p.97 / Chapter 5.9 --- Treatment of contaminated marine sediment in Kwun Tong Typhoon Shelter --- p.98 / Chapter 5.10 --- Treatment of sediment contaminated with sulphide in Hong Kong --- p.99 / Chapter 5.11 --- Other treatment method of sediment contaminated with sulphide --- p.100 / Chapter 5.12 --- Current limitations and abilities in identification of toxicants in pore water --- p.101 / Chapter 5.13 --- Improvement and Recommendations --- p.102 / Chapter 6. --- CONCLUSIONS --- p.104 / Chapter 7. --- REFERENCES --- p.105 / Chapter 8. --- APPENDICES --- p.125

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The visual image of the River Thames was central to the identity of London in the long eighteenth century. Art historical engagement with the subject has been dominated by refined upriver views, especially depictions of sites of royal residence and scenes of pageantry. This focus eclipses a significant untapped body of contemporary Thames imagery which suggests the existence of a more complex relationship between the visualisation of London's river and the larger social, ideological and economic contexts of Britain's rapidly developing global maritime and imperial power. This thesis proposes that only by reconnecting these works with the more familiar visual culture of eighteenth-century maritime London, can the full extent to which the river was identified as a signifier of national and imperial consciousness be fully understood. This identification is most apparent in depictions of the commercial and naval activity in the mercantile environs of the port to the east of London Bridge which effectively constitute a visual concordia discors with aggrandised upriver subjects. Thames imagery is also prevalent in the genre of satire where the countercultural nature of the port, characterised via its stereotypical portrayal of a bawdy labour force, undermines the polite pretensions of high art. In topographical views of the capital the dramatic physical rationalisation of the Thames in terms of new bridges and docks was harnessed to raise the profile of London and its river to that of an efficient cosmopolitan port suited for commercial empire. Above all, the image of the Thames evolved into a powerful and widely understood symbol reflecting a patriotic national identity constructed around maritime trade and naval power. This thesis argues for an alternative, more complex image of the Thames in the long eighteenth century which is informed by a range of ideological issues centred around the meaning of commerce and empire from a period when the river became the emblem of London's increasing self-identification as the centre of a maritime nation of unprecedented scale.

This thesis describes research performed into the segmentation and classification of features on images of wound terrain generated from an airborne millimetre wave radar. The principles of operation of the radar are established and it is shown how an image is produced from this particular radar. The parameters such as wavelength, antenna size and pulse length are related to the images and a mathematical description of the radar data is given. The effectiveness of established image processing techniques is reviewed when applied to millimetre wave radar images and a statistical classification technique is seen to yield encouraging results. This method of segmentation and classification is then extended to make optimal use of the available information from the radar. An orthogonal expansion of the Poincaré sphere representation of polarised radiation is established and it is shown how different terrain types cluster in the eigenspace of these spherical harmonics. Segmentation then follows from the clustering properties of pixels within this multidimensional eigenspace and classification from the locations of the clusters.

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No description available.