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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.
201

Mass Balance Model of Mercury for the St. Lawrence River, Cornwall, Ontario

Lessard, Charlotte 14 May 2012 (has links)
We have developed a regional mass balance model for the St. Lawrence River near Cornwall, Ontario that describes the fate and transport of mercury in three forms, elemental mercury (Hg0), divalent mercury (Hg2+), and methyl mercury (MeHg), in a five compartment environment (air, water, sediments, periphyton, and benthos). Our first objective was to construct a steady-state mass balance model to determine the dominant sources and sinks of mercury in this environment. Our second objective was to construct a dynamic mass balance model to predict and hindcast mercury concentrations in this environment. We compiled mercury concentrations, fluxes, and transformation rates from previous studies completed in this section of the river to develop the model in STELLA®. The inflow of mercury was the major source to this system, accounting for 0.42 mol month-1, or 95.5% of all mercury inputs, whereas outflow was 0.28 mol month-1, or 63.6% of all losses, and sediment deposition was 0.12 mol month-1, or 27.3% of all losses. The dynamic mass balance model provides estimated results that are consistent with measured data and predicts historical local industrial emissions to be approximately 400 kg year-1. Uncertainty estimates were greatest for advective fluxes in surface water, porewater, periphyton, and benthic invertebrates. This model is useful for predicting and hindcasting mercury concentrations in other aquatic environments because it contains the three main environmental compartments, all forms of mercury, and compartments (e.g. periphyton) not included in previous mercury multi-media models.
202

Hybrid Pre-coded ST-BC MIMO-CDMA System with Semi-blind Channel Estimation

Liao, Chong-Zhih 30 August 2011 (has links)
In this thesis, a novel pre-coded direct-sequence code division multiple access (DS-CDMA) associated with the multiple-input multiple-output (MIMO) antennas, along with Alamouti¡¦s space-time block code (ST-BC) is considered. In the transmitter, the idea of hybrid pre-coded is exploited; it can be employed to counteract the inter-symbol interference (ISI) introduced by the channel fading duo to multipath propagation, and can be used to exacting the full information of channel impulse response (CIR) in the receiver for semi-blind channel estimation. Under this transceiver framework, we develop a semi-blind adaptive MIMO-CDMA receiver, based on the linearly constrained constant modulus (LCCM) criterion, for symbol recovery. Furthermore, to reduce the complexity of receiver design, the framework of the generalized sidelobe canceller (GSC) associated with the recursive least-squares (RLS) algorithm is adopted, and the gradient approach is applied to track the desired user¡¦s amplitude, simultaneously, and is named as the GSC-CM-IQRD-RLS algorithm. Via computer simulations, the superior performance and the advantages of proposed scheme is verified; it outperforms the conventional LCMV-based algorithm, and slightly better than the convention CM-GSC-RLS receiver, with the paid of spectral efficient.
203

Performance Analysis of Complementary Code Based MIMO-CDMA Systems in Correlated Multi-Carrier Channels

Tsai, Tsung-chi 30 August 2005 (has links)
This thesis mainly focuses on the integration of Space-Time Block Coding (STBC) and Complementary Code based CDMA system. Our proposed integration systems have not only the merit of complementary code but also the extra advantage of diversity gain from STBC. Especially, when the different frequency channel gain has strong correlation, the complementary code will cancel most of interference.
204

Blood and water; the archaeological excavation and historical analysis of the Wreck of the Industry, a North-American transport sloop chartered by the British army at the end of the Seven Years' War: British colonial navigation and trade to supply Spanish Florida in the eighteenth century

Franklin, Marianne 12 April 2006 (has links)
In the 10-mer RNA duplex model system a 4-isocyano TEMPO spin-label is individually attached to one strand and two strands are annealed to measure distances. This methodology is limited to systems in which two oligonucleotides are annealed together. To circumvent this limitation and also to explore single-strand dynamics a new methodology was implemented, double spin-labeling. Double spin-labeled single-stranded RNA was investigated as a single-strand and within a duplex via MALDI-TOF-MS, EPR spectroscopy and RP-HPLC. A double spin-labeling strategy in this work will be applicable to large complex RNAs like Group I intron of Tetrahymena thermophilia. Captain Daniel Lawrence, was one of four sloops detailed to serve as a transport to supply the British Florida garrisons. The Industry ran aground on the bar outside of St. Augustine's harbour on May 6, 1764. The transport was carrying six-pound cannons, ammunition and artificer's tools. Further investigation of documents describing eighteenth-century trade and shipping to St. Augustine led to the discovery that the Lawrence family of sea captains provided a vital link between British New York and Spanish St. Augustine. An examination of the materials recovered from Site 8SJ3478 sheds light on exactly what a particular vessel carried during a period of transition in Florida's history.
205

Die Traditionen des Kollegiatstifts St. Kastulus in Moosburg /

Höflinger, Klaus. January 1994 (has links)
Texte remanié de: Diss.--Philosophische Fakultät für Geschichts- und Kunstwissenschaften--München--Ludwig-Maximilians-Universität, 1987. / Bibliogr. p. 263-281. Index.
206

The beginnings of evangelization in Eastern Uganda : 1895-1924 : an effort undertaken by the missionaries of St. Joseph's society, London - the Mill Hill missionaries /

Okello, Francis Xavier. January 2007 (has links)
Texte extrait de: Dissertazione--Facoltà di storia ecclesiastica--Pontificia università gregoriana. / Bibliogr. p. 201-205.
207

Food and feeding of the brine shrimp Artemia franciscana (Brazilian "Macau" population) in semi-intensive culture /

Campos, Alberto Alves, January 2000 (has links)
Thesis (M.Sc.), Memorial University of Newfoundland, 2000. / Bibliography: leaves 98-111.
208

The pharmacokinetics of oxytetracycline in Atlantic cod (Gadus morhua) /

Vatcher, Susan L., January 1999 (has links)
Thesis (M.Sc.), Memorial University of Newfoundland, 2000. / Bibliography: leaves 69-72.
209

Oil pollution and the Newfoundland and Labrador fishery : current and potential threats for the conservation of commercial fisheries resources in Placentia Bay /

Carew, Andrea M. E. January 2001 (has links)
Thesis (M.M.S.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 94-101. Also available online.
210

The impact of mobile fishing gear on benthic habitat and the implications for fisheries management /

McCallum, Barry R., January 2001 (has links)
Thesis (M.M.S.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 75-82.

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