Physical Sciences and Mathematics Commons^™

Generalised Surfaces In ℝ³, Brendan Guilfoyle, Wilhelm Klingenberg

Publications

The correspondence between 2-parameter families of oriented lines in ℝ³ and surfaces in Tℙ¹ is studied, and the geometric properties of the lines are related to the complex geometry of the surface. Congruences generated by global sections of Tℙ¹ are investigated, and a number of theorems are proven that generalise results for closed convex surfaces in ℝ³.

A Search For Tev Gamma-Ray Emission From High-Peaked Flat-Spectrum Radio Quasars Using The Whipple Air Cerenkov Telescope, P. T. Reynolds, Et. Al.

Physical Sciences Publications

Blazars have traditionally been separated into two broad categories based on their optical emission characteristics. Blazars with faint or no emission lines are referred to as BL Lacertae objects (BL Lacs), and blazars with prominent, broad emission lines are commonly referred to as flat-spectrum radio quasars (FSRQs). The spectral energy distribution of FSRQs has generally been thought of as being more akin to the low-peaked BL Lacs, which exhibit a peak in the infrared region of the spectrum, as opposed to high-peaked BL Lacs (HBLs), which exhibit a peak in UV/X-ray region of the spectrum. All blazars that are currently …

Tev Gamma-Ray Observations Of The Galactic Center, P. T. Reynolds, Et. Al.

Physical Sciences Publications

We report a possible detection of TeV gamma rays from the Galactic center by the Whipple 10 m gamma-ray telescope. Twenty-six hours of data were taken over an extended period from 1995 through 2003 resulting in a total significance of 3.7 σ. The measured excess corresponds to an integral flux of 1.6 × 10-8 ± 0.5 × 10-8 (stat) ± 0.3 × 10-8 (sys) photons m-2 s-1 above an energy of 2.8 TeV, roughly 40% of the flux from the Crab Nebula at this energy. The 95% confidence region has an angular extent of about 15' and includes the position …

Xmm-Newton Observations Of The Bl Lac Ms 0205.7+3509: A Dense, Low-Metallicity Absorber, Niall Smith, Et. Al.

Blackrock Castle Observatory Publications

The high-frequency-peaked BL Lac, MS 0205.7+3509 was observed twice with XMM-Newton. Both X-ray spectra are synchrotron-dominated, with mean 0.2–10 keV fluxes of and  erg cm^-2 s^-1. The X-ray spectra are well fit by a power-law with absorption above the Galactic value, however no absorption edges are detected, implying a low metallicity absorber () or an absorber with redshift above one (best-fit for an absorber with solar abundances). In either case the absorbing column density must be  cm^-2. A new optical spectrum is presented, with a absorption doublet detected at , but no other significant …

Constraints On The Very High Energy Emission From Bl Lacertae Objects, P. T. Reynolds, Et. Al.

Physical Sciences Publications

We present results from observations of 29 BL Lacertae objects, taken with the Whipple Observatory 10 m gamma-ray telescope between 1995 and 2000. The observed objects are mostly at low redshift (z < 0.2), but observations of objects of up to z = 0.444 are also reported. Five of the objects are EGRET sources and two are unconfirmed TeV sources. Three of the confirmed sources of extragalactic TeV gamma rays were originally observed as part of this survey and have been reported elsewhere. No significant excesses are detected from any of the other objects observed, on timescales of days, months, or years. We report 99.9% confidence level flux upper limits for the objects for each observing season. The flux upper limits are typically 20% of the Crab flux, although for some sources, limits as sensitive as 6% of the Crab flux were derived. The results are consistent with the synchrotron self-Compton model predictions considered in this work.

Observation Of M87 At 400 Gev With The Whipple 10 Meter Telescope, P. T. Reynolds, Et. Al.

Physical Sciences Publications

We present results from observations taken with the Whipple 10 m very high energy γ-ray telescope with maximal sensitivity at 400 GeV during 39 hr between 2000 and 2003 in the direction of the giant radio galaxy M87. Using the entire data set, we derive a 99% confidence level upper limit on the flux of γ-ray emission above 400 GeV from M87 to be ≤6.9 × 10-12 cm-2 s-1. This suggests variability at the 90% confidence level when compared to the flux measured by the HEGRA collaboration in 1999 if the differential spectrum is steeper than a power law of …

The Synthesis And Characterisation Of Diiron And Triiron Carbonyl Cluster Compounds With Sulphur And Phosphine Ligands, Geraldine Gray

Theses

This work is primarily concerned with the synthesis and characterisation of di and triiron carbonyl cluster derivatives which contain sulphur and phosphine ligands.

The first chapter is a review of the literature of such complexes. Included are diiron carbonyl clusters which contain phosphine ligands, those which contain sulphur, and those that contain phosphine and sulphur ligands. Triiron carbonyl clusters which contain phosphine ligands, sulphur ligands and both are also discussed.

Chapter two describes the synthesis of compounds of the type [{Fe₂(SR)₂(CO)₅)₂Ph₂P (CH₂)_nPPh₂] (R = …

Multi-Path Differential Optical Absorption Spectroscopy, John Gerard Murphy

Theses

A number of potential methods for the production of multiple light beams for long- path differential absorption spectroscopy have been considered and analysed. The system deemed most suitable has been designed, constructed and tested over two adjacent measurement paths.

The system was built in Cork Institute of Technology to the west of Cork City, Ireland during the period 2000 - 2004. The system has been tested during the winter period of 2003/2004 and ambient concentrations of SO₂ and NO₂ have been measured and are reported. The measurement of additional gaseous species and suspended particulate matter was excluded from …

Integrating Experiments And Simulators Into A Distributed E-Learning Environment, Frank Koehler

Theses

New information and communication technologies have emerged in the last few years which have made an impact on learning at all levels. At universities, the spectrum of learning support ranges from enriching traditional lectures and courses with multi- media elements to complete web-based interactive learning environments. A special aspect based on the new media technologies is learning within model worlds by use of simulations or real-life experiments. There are normally no links between these applications and the learning content, so it is impossible to tap the full potential of these applications. Research activities in the area of e-learning underline the …

Optimisation Of Heat Transfer And Fluid Flow In The Cooling Of Building Integrated Photovoltaic Facades., Eoin Patrick Hodge

Theses

The aim of this research was to explore the effects of mature and developing technologies from aeronautical industries such as impingement and film cooling, and electronic cooling techniques, in the setting up of different laminar and turbulent flow regimes on PV cooling duct heat transfer rates, with air flow as that brought about with natural buoyancy effects in a vertical building facade. The problem of efficiency losses in PV panels, due to overheating, is one of the factors restricting the development and use of this renewable power source. PV panels can experience very high temperatures, due to the heat input …

A Proposal To Meet The Biofuels Directive In Ireland, Karl Mccarthy

Theses

In 1990 the transport sector accounted for 9,5% of all Irish emissions. By 2010 it is predicted that transport emissions will have increased by 179%, accounting for 18.8% of all emissions. It is predicted that transport emissions will therefore be around 14,000 kt in 2010. This equates to around €370 million pa in carbon taxes if and when the taxation regime is introduced. This €370 million may be used to facilitate a biofuel industry (for example, by reducing excise duty on biofuels).

The proposed carbon tax along with the EU Biofuels Directive aims to encourage the use of renewable transport …

Speech Enabled E-Learning Technology For Adult Literacy Tutoring, Jason Meade

Theses

This research presents the work involved in developing a speech-enabled e-Learning prototype for use in literacy tutoring. As the main objective was to develop an interface for literacy learning, initial research concentrated on establishing a framework for literacy e-Leaming through the use of speech technology. Requirements for best practice e-Learning and the relevance of learning theories to an e-Learning application were also investigated. The technologies to facilitate this, such as text to speech technologies and mark-up languages, were addressed during the implementation of speech-enabled prototypes. Both server-side and client-side prototypes were implemented to investigate speech technology. Testing found the server-side …

Investigation Of Implementation Techniques For Backpropagation Neural Networks, John Culloty

Theses

Artificial neural networks are biologically inspired computational methods that have the ability to approximate discrete, real and vector valued target functions. For some problem domains this ability makes neural networks a more appealing solution than traditional computational techniques. Such problem domains typically contain a large number of parameters that are interrelated in a complex and often unknown manner. This makes rule based solutions all but impossible. However another feature of such problem domains is the presence of large volumes of real world data that can be used to tram a neural network until it learns the solution.

One of the …

Development Of Electrochemical Sensors For Monitoring Glucose, Michael Nesbitt

Theses

The thesis focuses on evaluating calcium alginate as an immobilisation matrix for the oxidase enzyme glucose oxidase for the amperometric determination of glucose. The basic principles of enzymology and enzyme immobilisation is discussed followed by a review of a variety of first, second and third generation type enzyme electrodes. Amperometry as governed by the Cottrell equation and mass transfer models relating to amperometric electrodes are also considered.

Bovine serum albumin (BSA / GOx) enzyme electrode system was employed as a model to evaluate a calcium alginate immobilisation technique for glucose oxidase. The principal methods employed for enzyme immobilisation were:

• …

Investigation Of Implementation Techniques For Backpropagation Neural Networks., John Culloty

Theses

Artificial neural networks are biologically inspired computational methods that have the ability to approximate discrete, real and vector valued target functions. For some problem domains this ability makes neural networks a more appealing solution than traditional computational techniques. Such problem domains typically contain a large number of parameters that are interrelated in a complex and often unknown manner. This makes rule based solutions all but impossible. However another feature of such problem domains is the presence of large volumes of real world data that can be used to tram a neural network until it learns the solution.

One of the …

A Toolkit For Xml-Based And Process-Oriented Application Integration, Volker Münch

Theses

Systems integration is hard work; different architectures with different interfaces and an innumerable amount of Legacy applications with non-standard interfaces exist. However the needs to meet changing business requirements and to implement faster and optimised procedures within an enterprise and in cooperation with other external enterprises mean that there is a continuing demand for such integration strategies and products. Integration was often an activity separate from system development and could not be accomplished without re-involving system designers and developers. Such a process is therefore inefficient and costly. This thesis proposes a process-oriented integration strategy that combines the tasks of integration …

On The Space Of Oriented Affine Lines In R-3, Brendan Guilfoyle, Wilhelm Klingenberg

Preprints

We introduce a local coordinate description for the correspondence between the space of oriented affine lines in Euclidean R 3 and the tangent bundle to the 2-sphere. These can be utilised to give canonical coordinates on surfaces in R 3 , as we illustrate with a number of explicit examples