Physical Sciences and Mathematics Commons^™

Information Brokerage - A New Approach Using Knowledge Management, Robert Loew

Theses

Traditional knowledge management attempts to store the total enterprise knowledge into IT related structures, but knowledge management strategies should focus also on people and organisations and not just on technology.

This can be addressed in part by communicating knowledge between people, in and across organisations. Such communication focuses on the development and exchange of people’s experience.

This thesis introduces a hybrid knowledge management solution consisting of an automated system that includes people: employees, experts and Knowledge Brokers (KB). The hybrid concept supports the identification of suitable people for certain topics of discussion. Further, it supports the knowledge communication process by …

Characterisation Of Immunosensor Surfaces Using Scanning Force Microscopy, Eva Maria Gil Romero

Theses

The overall aim of this thesis was twofold. Firstly, to evaluate how scanning force microscopy (SFM) could be used to characterise the surfaces of immunosensors. Four aspects of immunosensor characteristics where SFM has particular application potential have been identified: (a) immobilisation chemistry and (b) the surface density, (c) orientation and (d) specificity of the immobilised antibodies. Secondly, to examine experimentally how the Explorer SFM instrument could be used for such characterisation.

The Explorer SFM instrument is of an open-loop actuator design that is exposed to the intrinsic inadequacies of piezoelectric actuators. In this regard, careful calibration has shown that achieving …

Fluoride And Phosphate Glass Whispering Gallery Micro-Resonators, Jonathan Ward

Theses

This PhD work focuses on spherical microlasers made from commercial and experimental laser glasses. The laser light in a microsphere is confined in a region called a whispering gallery mode, which has unique properties that allow for many nonlinear effects to be observed with only sub-mW pump powers. Efficient coupling of light into the microsphere is attained by using adiabatically tapered fibres fabricated using various heating methods including a CO₂ laser, a sapphire tube furnace and electric heaters. However, the best result is obtained using a fibre pulling rig with an oxy-butane torch as the heat source. This system …

Ultrafast Carrier Dynamics Of An Inas/Gaas Semiconductor Quantum Dot Absorber, Gillian Emma Madden

Theses

High-speed semiconductor quantum dot saturable absorbers have dramatically improved lasers to generate ultrafast optical pulses with a diverse range of applications. The carrier escape and relaxation dynamics of an InAs/GaAs quantum dot absorber waveguide were investigated using a heterodyne pump-probe spectroscopy technique. The measurements of the absorption recovery of the quantum dot waveguide were performed under applied reverse bias utilising both single-colour and two-colour pump probe spectroscopy. The study revealed differences in the intradot relaxation dynamics related to the initial population of the ground state or the excited state of the quantum dots. It was concluded that phonon mediated recovery …

Automated Network Planning For Industrial Ethernet Networks, Holger Machens

Theses

Engineers usually use computer aided methods to ease the increasingly complex planning task of automation plants. One such computer aided method for automated planning of Industrial Ethernet networks under given network QoS requirements is presented in this thesis. The method is based on partitioning the given set of network nodes according to specified communication relationships between the nodes, thereby creating subsets of nodes which are joined using given networking algorithms. Several networking algorithms may be applicable for each subset of nodes and any complete solution is a combination of several partial solutions, one for each subset of nodes. Enumeration through …

Manipulation Tools For Laser-Cooled Rubidium Atoms : Ultrathin Optical Fibres And Magnetic Diffraction Gratings / Michael J. Morrissey., Michael J. Morrissey

Theses

This thesis describes the construction and characterisation of a standard six-beam configuration magneto-optical trap (MOT) used to cool and trap neutral ⁸⁵Rb atoms. This system is capable of producing a cloud of ~10⁸ atoms whose average temperature is in the sub-Doppler range. The fabrication process for the production of subwavelength tapered optical nanofibres (TONFs) is also described, as well as their guiding properties. These have many proposed applications in the field of cold atoms. However, significant technical progress must be made before many of these applications can be realised. The objective of the research work was to combine …

Application Of Multiple Mass Spectrometric Techniques In The Isolation, Determination And Characterisation Of The Marine Toxins; Azaspiracid, Keith O'Callaghan

Theses

The Azaspiracids are a class of polyether marine biotoxins that present a significant health risk to consumers of shellfish. Since their discovery in the late 1990s several human intoxications have been reported, and traced to Irish shellfish farms resulting in closures or harvest rejections. As such incidents involving azaspiracid shellfish poisoning have a major socio-economic impact on communities that rely on shellfish farming revenues.

Recent evidence suggests that azaspiracid poisoning events may become more commonplace. With this increased risk the understanding of azaspiracids mode of action and biological targets becomes crucial. To support these endeavours effective analytical methods need to …

The Geometry Of The Space Of Oriented Geodesics Of Hyperbolic 3-Space, Nikos Georgiou

Theses

In this thesis we construct a Kähler structure (J, Ω, G) on the space L(H³) of oriented geodesics of hyperbolic 3-space H³ and investigate its properties. We prove that (L(H³),J) is biholomorphic to (see thesis pdf), and that the Kähler metric G is of neutral signature, conformally flat and scalar flat.

We establish that the identity component of the isometry group of the metric G on L(H³) is isomorphic to the identity component of the hyperbolic isometry group. We show that the geodesics of G correspond to ruled minimal surfaces in H3, which …