Physical Sciences and Mathematics Commons^™

Measured Stark Widths Of A 425,94 Nm Ari Spectral Line, Ljiljana Skuljan, Vladimir Milosavljevic, Aleksandar Sreckovic, Stevan Djenize

Articles

No abstract provided.

Chp And Energy Conservation, Jim Mcgovern

Articles

The principles of the use of 'combined heat and power' (CHP) for the achievement of fuel energy conservation, minimisation of environmental impact and economic advantage are explained. A distinction is made between the two types of outputs: heat and work. It is argued that an efficiency value that is defined as the sum of the heat and work outputs divided by the energy of the fuel used is not very meaningful. An alternative, rational, efficiency is explained. It is concluded that CHP is an option to be considered where both heating and power are required, but is not a general …

A New Photopolymer Recording Material For Holographic Applications: Photochemical And Holographic Studies Towards An Optimized System, Suzanne Martin

Doctoral

Photopolymer materials are a practical alternative to high resolution silver halide photographic emulsions for the recording of holograms and high spatial frequency holographic gratings. The new holographic recording material reported in this thesis consists of a green sensitive dye (erythrosine B), an electron donor (triethanolamine), and a monomer mixture (acrylamide and methylene bisacrylamide) in a polyvinyl alcohol binder. ON illumination with light of the appropriate wavelength the dye absorbs a photon and the excited triplet state of the dye reacts with the electron donor to produce free radicals. These free radicals may then initiate local polymerization of the monomer. The …

The Trace Of An Abelian Group:An Application To Digraphs, J. M. Burns, Brendan Goldsmith

Articles

The trace of a finite Abelian group is used to give a short proof of a result of Arlinghaus and Harary on the digraph number of such a group

Experimental Stark Shift Of Several Nii And Oii Spectral Lines, Mara Scepanovic, Vladimir Milosavljevic, Stevan Djenize, Mihajlo Platisa, Jaroslav Labat

Articles

Stark shift of four NII and seven OII spectral lines have been measured for the first time in the linear low pressure pulsed arc plasma and compared with existing theoretical values.

Dielectric Response Of Ferroelectric Liquid Crystal Cells, Yuri Panarin, Huan Xu, Seamus Mac Lughadha, Jagdish Vij

Articles

No abstract provided.

On Endomorphisms And Automorphisms Of Some Pure Subgroups Of The Baer-Specker Group, A. L.S. Corner, Brendan Goldsmith

Articles

The endomoprhism algebras of certain pure subgroups of the Baer-Specker group are investigated to answer a question of Irwin. Automorphism groups of these Abelian groups are investigated and a realization theme is established.

Cyclic Voltammetry Of Polypyrroledodecylbenzenesulfonate Layers, T. Mccormac, W. Breen, A. Mcgee, John Cassidy, M. E.G. Lyons

Articles

Polypyrrole was deposited from solutions of NaCIO. and NaDBS, where DBS is dodecylbenzenesulfonate in aqueous solu\ion and characterizcd by voltammetry. It is found that the absence of the so-called 'double laver charging current' during cyclic voltammetry of the layers formed from solutions with surfactant is not because of' the" order in morphology of the layer, but irreversible incorporation of' the surfactant anion.

Resonant Vibrations Of The Irish Folk Harp, Patrick Healy

Other Resources

An analysis of the resonant vibration of an O’Meachair cedar and mahogany Irish folk harp is reported. A report is also made of a small number of measurements carried out on an O’Meachair spruce and maple Irish folk harp. The structure and operation of the harp is described.

The theory of small vibrations of plates and wooden boards is set out.

The system devised to measure input admittance at driving points on the harp body over a frequency range O-2 kHz is described. Tests of its linearity and out of its frequency flatness are reported.

Resonant vibrations of an isolated …

On Quasi-Permutation Representations Of Finite Groups, J. M. Burns, Brendan Goldsmith, B. Hartley, R. Sandling

Articles

In [6], Wong defined a quasi-permutation group of degree n to be a finite group G of automorphisms of an n-dimensional complex vector space such that every element of G has non-negative integral trace. The terminology derives from the fact that if G is a finite group of permutations of a set ω of size n, and we think of G as acting on the complex vector space with basis ω, then the trace of an element g ∈ G is equal to the number of points of ω fixed by g. In [6] and [7], Wong studied the extent …

Cotorsion-Free Algebras As Endomorphism Algebras In L - The Discrete An Topological Cases., R. Gobel, Brendan Goldsmith

Articles

The discrete algebras A over a commutative ring R which can be realised as the full endomorphism algebra of a torsion-free R-module have been investigated by Dugas and Gobel under the additional set-theoretic axiom of constructibility, V = L. Many interesting results have been obtained for cotorsion-free algebras but the proofs involve rather elaborate calculations in linear algebra. Here these results are rederived in a more natural topological setting and substantial generalizations to topological algebras (which could not be handled in the previous linear algebra approach) are obtained. The results obtained are independent of the usual Zermelo-Fraenkel set theory ZFC.

The Walker Endomorphism Algebra Of A Mixed Module, Brendan Goldsmith, P. Zanardo

Articles

Archimedian valuation domains R are characterised in terms of the endomorphism algebras of non-splitting mixed modules of rank 1, in the Walker category.

The Kaplansky Test Problems - An Approach Via Radicals, R. Gobel, Brendan Goldsmith

Articles

The existence of non-free, K-free Abelian groups and modules (over some non-left perfect rings R) having prescribed endomorphism algebra is established within ZFC + 0 set theory. The principal technique used exploits free resolutions of non-free R-modules X and is similar to that used previously by Griffith and Eklof; much stronger results than have been obtained heretofore are obtained by coding additional information into the module X. As a consequence we can show, inter alia, that the Kaplansky Test Problems have negative answers for strongly K,-free Abelian groups of cardinality K1 in ZFC and assuming the weak Continuum Hypothesis.

Aspects Of Gold Recovery From An Indigenous Ore, Cormac Patrick Mcnamee

Masters

This project involved the investigation into the basic electrochemistry of the thiourea-formamidine disulphide redox couple and an estimation of the formal potential, Eo1 for the couple. By carrying out optimisation experiments on the leaching of gold from an ore sample from the Avoca mine in Co. Wicklow, the optimum leaching conditions were determined for maximum gold extraction. The effects of various organic and inorganic species on the adsorption of gold onto activated carbon and modified peat were investigated with the use of factorial designed experiments. The Langmuir Isotherm model was applied to estimate the capacity of the carbon for these …

Hysteresis And Anchoring Energy In Ferroelectric Liquid Crystals, Yuri Panarin

Articles

The frequency dispersion of the coercive force of Ferroelectric Liquid Crystals (FLC) cells has been detected and examined in the range of infralow (lower than 0.1 Hz) frequencies. To clarify the low-frequency dispersion, the model has been suggested, based on the arrangement of free charges and well describing the experimental curves. The method for determination of the energy of FLC anchoring at the surface, developed on the basis of the static hysteresis loop, has been proposed. The dependence of bistability and the anchoring energy upon the orientant layer thickness has experimentally been investigated.

Some Developments In Information Technology In The Irish Hotel And Catering Industry, Sean Connell, Elaine Sunderland, Ciaran Mcdonnell

Conference papers

This paper describes the current and potential future use of computers in the Hospitality Industry in Ireland. It briefly outlines two research projects which are being carried out in the Dublin College of Catering in the application of computers to the Industry.

Applying Metrics To Rule-Based Systems, Paul Doyle, Renaat Verbruggen

Other

Since the introduction of software measurement theory in the early seventies it has been accepted that in order to control software it must first be measured. Unambiguous and reproducible measurements are considered to be the most useful in controlling software productivity, costs and quality, and diverse sets of measurements are required to cover all aspects of software. This paper focuses on measures for rule-based language systems and also describes a process for developing measures for other non-standard 3GL development tools. This paper uses KEL as an example and the method allows the re-use of existing measures and indicates if and …

A Case For The Use Of Application Generators In The Creation Of Software For The Hotel Industry, Peter O'Connor, Ciaran Mcdonnell

Conference papers

The article makes the case for the use of Program Generators in producing software for the Hotel and Catering Industry

Degnerate Four-Wave Mixing In Rhodamine Doped Epoxy Waveguides, B. Rossi, Hugh Byrne, W. Blau

Articles

Self-diffraction from laser-induced gratings is observed in a 13 pm-thick film of rhodamine I3 doped epoxy. The decay of the grating is measured to be 2.05 ns. Degenerate forward four-wave mixing in a guided geometry is observed by coupling out all beams after nronagation over 1 mm. At 595 nm the third-order nonlinear susceptibility of the film is measured to be 1.5~10-‘~ m2Ve2.

Shadow Casting Phenomena At Newgrange, Frank Prendergast

Articles

A digital model of the Newgrange passage tomb and surrounding ring of monoliths known as the Great Circle is used to investigate sunrise shadow casting phenomena at the monument. Diurnal variation in shadow directions and lengths are analysed for their potential use in the Bronze Age to indicate the passage of seasonal time. Computer-aided simulations are developed from a photogrammetric survey to accurately show how three of the largest monoliths, located closest to the tomb entrance and archaeologically coded GC1, GC-1 and GC-2, cast their shadows onto the vertical face of the entrance kerbstone, coded K1. The phenomena occur at …

On Separable Torsion- Free Modules Of Countable Density Character, R. Gobel, Brendan Goldsmith

Articles

The endomorphism algebras of modules of large cardinalities have been extensively studied in recent years using the combinatorial set-theoretic techniques of Shelah-the so-called black-box methods (see, e.g., [4, 5, 151). Despite the spectacular success of these methods, they are not suitable for realization theorems at small carinalities. Of course at the level of countability (or rather more generally for cardinals ~2’~) there are in some cases the original dramatic results of A. L. S. Corner [ 1, 2, 31 and the more recent generalizations of Gobel and May [ 111. Very recently the study of realization problems at cardinalities

Mixed Modules In L, R. Gobel, Brendan Goldsmith

Articles

By assuming the set-theoretic hypothesis V = L we show that, for a large class of rings R, there exist, for any regular not weekly compact cardinals K, strongly k-cyclic mixed R-modules having endomorphism algebra isomorphic to the split extension of the R-algebra A by the ideal of bounded endomorphism provided A is free qua R-module and K./Az/

On Almost-Free Modules Over Complete Discrete Valuation Rings, Brendan Goldsmith, R. Gobel

Articles

No abstract available

Maximal Order Abelian Subgroups Of Symmetric Groups, J. M. Burns, Brendan Goldsmith

Articles

No abstract available

Reactions Of Hydroxyl Radicals And Chlorine Atoms With Compounds Of Group Iv Elements., Denis J. O'Farrell

Doctoral

Rate data are reported for the reaction of hydroxyl radicals with a series of substituted silanes. The data presented suggest the presence of polar effects in the transition state. Good agreement is reported between a relative rate study and an absolute rate study, Table (i). The corresponding reaction of chlorine atoms with the series of substituted silanes support the suggestion of polar effects in the transition state, Table (ii). Rate data are also reported for the reaction of hydroxyl radicals with a series of tetramethyl and tetraethyl compounds of the Group IV elements. The data presented show an enhanced reactivity …

A Note On Coslender Groups, R. Dimitric, Brendan Goldsmith

Articles

The notion of a coslender group has been introduced previously by the first author. This work continues the investigation of such groups, defines coslender part of a group, proves embeddability results, gives a characterization of finite rank coslender grops, and proves a result on smooth ascending chains of coslender groups with a conjecture that every countable coslender torsion free group is a smooth ascending union of finite rank coslender pure subgroups.

Essentially Indecomposable Modules Which Are Almost Free, Brendan Goldsmith, R. Gobel

Articles

No abstract provided

On Endomorphism And Automorphisms Of Some Torsion-Free Modules, Brendan Goldsmith

Articles

The relationship between the endomorphism ring and the automorphism group of an abelian p-group has been extensively investigated. It is known that theautomorphism group need not generate the full endomorphism ring. In this paper we investigate the analagous problem for torsion free modules over a complete discrete valuation ring obtaining similar results.

Structural, Remote Sensing And Multivariate Correlation Methods As Aids To Mineral Exploration, Central Ireland, D.W. Coller, M.F. Critchley, J.M. Dolan, Ciaran Mcdonnell, C.J. Murphy, W.E.A. Phillips, D.J. Sanderson

Books/Book chapters

This work discusses structural, remote sensing and multivariate correlation methods as aids to mineral exploration in West Central Ireland. The work was performed as part of the EU-funded CREST project.

Realising Rings As Endomorphism Rings: The Impact Of Logic, Brendan Goldsmith

Articles

No abstract available