Reconfiguration is needed to meet the fight-through and survivability requirements of a shipboard power system. Reconfiguration involves the re-arrangement of power system topology through the opening and switching of breakers, and adjusting of total generators and load values. When the power system is reconfigured, the protection system needs to be attuned to the new power system state. This thesis focuses on developing an adaptive protection scheme for shipboard power systems that will automatically update relay settings after changes in power system topology and operational state. The developed adaptive protection scheme employs four main algorithms to achieve its goal. A topology-recognition algorithm uses the statuses (open/close) of breakers to determine the topological-configuration of the system. A powerlow and a fault-analysis algorithm are used to determine the system?s normal and fault currents, respectively. A protection-setting algorithm is used to determine and set the operating parameters of all the relays in the system. The scheme was implemented in MATLAB miles and tested on various configurations of a notional shipboard power system. The tests results were verified in CAPE.

Thesis (Ph. D.)--Rugers, The State University of New Jersey, 1997. / Includes abstract and vita. Includes bibliographical references (p. 245-257).

by Li Man Him. / Thesis (M.B.A.)--Chinese University of Hong Kong, 1975. / Includes bibliographical references. / Summary in Chinese.

As an important technique for corrosion control in marine environment, Cathodic Protection (CP) should be applied with a full understanding of environmental conditions and a good consideration of current requirements. Early studies on different kinds of steel specimens in the intertidal zone show severe corrosion losses. Nevertheless, there is evidence that CP can work in these regions of a steel structure because electrolyte pathway can remain some time on thin wetted surfaces when tides recede. This research aims to study corrosion activities and their behaviour under the influence of CP in a thin layer of electrolyte as a simulation of the inter-tidal zone. By means of a mechanical vibrating probe, Scanning Vibrating Electrode Technique (SVET) may be used to study local activities at coating defects in a thin electrolyte layer. The effect of CP on the local currents at the defect site was confirmed by SVET and, significantly, the development of calcareous films under these conditions in seawater was also observed. Such films are found to be effective in the absence of cathodic polarisation and only failed after damage. In order to explore the performance of applying CP, a Finite Element (FE) model of electrically connected zinc and steel samples beneath a specific thickness of electrolyte has been created, with full polarisation curves implemented for each metal based on experimental results obtained. The influence of the electrolyte conductivity and the geometry of the electrodes has also been considered. A comparison can then be made between experimental investigation and computational modelling of this corrosion cell. Epoxy-coated and uncoated mild steel samples obtained in the simulated tidal facility were also investigated. The formation of calcareous films was confirmed. Calcareous films were protective under these intermittent wetting conditions. Techniques used to understand the performance include optical observation, Scanning Electron Microscopy (SEM) together with Energy Dispersive X-ray (EDX) and X-ray Diffraction (XRD) analysis.

Thesis (M.Sc. (Plant protection )) --University of Limpopo, 2011 / Monsonia burkeana is widely used as a decoction for plant protection in South Africa. However, the accumulative capabilities (ACs) for essential nutrient elements and phenolic-antioxidant relationship in its organs are not documented. A study was conducted to determine whether: (1) the ACs for nutrient elements in fruit, leaf, stem and root of M. Burkeana were similar, (2) total phenolic and antioxidant contents in fruit, leaf, stem and root of M. burkeana were distributed equally, and (3) phenolic levels have an effect on accumulation of antioxidants in the four organs. Ten plants per plot, with three replicates, were harvested whole, oven-dried and separated into the four organs and then quantified for the above enlisted variables. The ACs for essential nutrient elements differed among the four organs. Generally, reproductive organs and leaves had high ACs for macro-nutrients, whereas roots had high ACs for micro-nutrients. Similarly, reproductive organs and leaves were good sources of phenolic and antioxidant compounds. Saturation factors in various organs of M. burkeana suggested that more than 90% of antioxidants were derivatives of the phenolic compounds. Optimum levels of antioxidant activities were attained at 5.39, 5.49, 4.36 and 4.13 mg/ 100 g of phenolic content in fruit, leaf, stem and root, respectively. Consequently, M. burkeana organs have the potential to provide fertiliser effect on crops, and both phenolics and antioxidants required as active ingredients for sprays used in plant protection. / the National Research Foundation,the National Department of Agriculture,Forestry and Fisheries,the National Department of Science and Technology

Thesis (M. Sc.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 107-116).

published_or_final_version / Public Administration / Master / Master of Social Sciences

Thesis (Ph. D.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 383-429).

Thesis (M. Sc.)--University of Hong Kong, 1994. / Includes bibliographical references.

Thesis (M. Sc.)--University of Hong Kong, 1993.