Physical Sciences and Mathematics Commons^™

Quantitative And Qualitative Assessment Of Groundwater Resources In Al-Khatim Area, Uae, Ahmed Khaled Othman

Theses

The UAE has achieved remarkable progress in transformation from separated small emirates to a modern union country with a high standard of living. The country is however, considered an extreme arid region.

In spite of these harsh conditions, The UAE government has encouraged plantation in towns, villages and country side. This has led to sharp increase in the agricultural sector particularly during the last three decades. As the irrigated land kept increasing, there was a deep concern about the water demand and the impact of agriculture activities on groundwater systems. Al-Khatim area is considered one of the most important agricultural …

Radio Resource Management For Cellular Wireless Local Area Networks., Olivia Brickley

Theses

The growing demand for mobile computing worldwide has led to the increasing deployment and use of Wireless Local Area Networks (WLANs) in the last number of years. During this time, user requirements have evolved, resulting in a more diverse mix of services being carried over the wireless medium. In particular, delay sensitive real-time applications such as streaming multimedia and voice over IP are growing in importance. The widely accepted IEEE 802.11b standard, however, was not designed with sufficient Quality of Service (QoS) constraints for such applications. A new draft of the standard named 802.1 le has been proposed that deals …

Salmonella Infection Among Farm Animals In Al Ain, United Arab Emirates., Dalal Saeed Saeed Mansour Al Kaabi

Theses

Salmonellosis is considered one of the most economically significant diseases, affecting man and different animals. The disease affects all ages of domesticated and wild living animals. Salmonellosis manifests a variety of clinical signs such as diarrhea, abortion, arthritis and respiratory problems. The natural habitat of Salmonella species is the intestinal tract of most animal species. Carrier animals represent a continuous source of shedding the bacteria in the surrounding environment. Salmonella infection among animals and then to man causing public health hazard.

In this study, a total of 882 samples were collected from different animal species in Al Ain area of …

A Salt On The Land: The Osmolyte Production And Physiological Responses Of Selected Myrtaceae Species Exposed To Salt And Water Stress, Janelle Atkinson

Theses: Doctorates and Masters

Glasshouse trials were conducted on Calothamnus quadrifidus, Eucalyptus camaldulensis and Melaleuca uncinata

to test relative tolerance and uniformity of response in the Myrtaceae family to salt, waterlogging and salt x waterlogging. Seed sources from both saline (SA) and non-saline areas were used to compare differences in survival, growth and proline production to these stresses.

Opto-Vlsi Processing For Reconfigurable Optical Devices, Chung-Kiak Poh

Theses: Doctorates and Masters

The implementation of Wavelength Division Multiplexing system (WDM) optical fibre transmission systems has the potential to realise this high capacity data rate exceeding 10 Tb/s. The ability to reconfigure optical networks is a desirable attribute for future metro applications where light paths can be set up or taken down dynamically as required in the network. The use of microelectronics in conjunction with photonics enables intelligence to be added to the high-speed capability of photonics, thus realising reconfigurable optical devices which can revolutionise optical telecommunications and many more application areas. In this thesis, we investigate and demonstrate the capability of Opto-VLSI …

The Pedagogical And Practical Issues Of Using Ict In Post-Primary Schools, Kay O'Sullivan Mc Carty

Theses

This study was an investigation into some of the pedagogical and practical issues that need to be considered when using ICT, with particular reference to post-primary schools. This investigation was prompted by the introduction of broadband into Irish schools in the next twelve months. Resources need to be developed that are subject specific and relevant to the Irish curriculum. The principle learning theories were examined and their pedagogical implications for post-primary teachers were discussed. The definition of learning styles was explored, different measurements were looked at and several internet based inventories were examined. The VARK questionnaire was administered to a …

Environment Friendly Organic Synthesis Using Bismuth Compounds. An Efficient Method For Carbonyl-Ene Reactions Catalyzed By Bismuth Triflate, Ram Mohan, Erin Anderson, Justin Ernat, Mai Nguyen, Ann Palma

Scholarship

Bismuth triflate (0.1 mol %) is a highly efficient catalyst for the cyclization of citronellal 1, a reaction that yields a ratio of 80:20 of isopulegol 2 and neoisopulegol 3. This methodology has also been extended to the synthesis of substituted piperidines. The bismuth triflate catalyzed ene reaction of aldehyde 4 gives a 70:30 mixture of piperidines 5 and 6. The advantages of these methods include the use of a highly efficient catalyst that is relatively nontoxic, cheap and easy to handle.

The Discovery-Oriented Approach To Organic Chemistry. 6. Selective Reduction In Organic Chemistry: Reduction Of Aldehydes In The Presence Of Esters Using Sodium Borohydride, Ram Mohan, Ashvin Baru

Scholarship

Chemoselective reductions are valuable in organic synthesis and are routinely discussed in a sophomore organic chemistry course. Yet, there are few examples of laboratory experiments that illustrate such chemoselectivity. A reaction that is routinely discussed in sophomore organic chemistry is the selective reduction of aldehydes and ketones using sodium borohydride. Esters are typically not affected by NaBH₄. However, none of the lab experiments reported to date illustrate this chemoselectivity (1). We have developed a discovery-oriented lab experiment that illustrates the chemoselective nature of reductions using sodium borohydride. The experiments involve the reduction of vanillin acetate (Scheme I) …

Efficacy Of Innovative Anti-Microbial Decontamination Of Minimally Processed Vegetables, Christina Busquets I Tortosa

Masters

Chlorine has widespread use commercially as a disinfectant wash for raw vegetables. However, it is an extremely corrosive gas and it may have severe health and environmental implications. The aim of this thesis was to find safe, alternative decontamination treatments for ready-to-eat Iceberg lettuce. The efficacy of 1% acetic acid, 2% citric acid; calcium lactate concentrations of 0.5%, 1.5%, 2.5% and 3% at wash temperature of 4,25 and 50°C, ozone alone (1 mg 1-1) and in combination with calcium lactate (2.5%) were compared with chlorine as decontaminating treatments. Microbiological analyses were performed following decontamination treatments using the pour plate method …

Study Of An Acrylamide-Based Photopolymer For Use As A Holographic Data Storage Medium, Hosam Sherif, Izabela Naydenova, Suzanne Martin, Colm Mcginn, G Berger, C Denz, Vincent Toal

Conference Papers

An acrylamide-based photopolymer formulated in the Centre for Industrial and Engineering Optics has been investigated with a view to further optimisation for holographic optical storage. Series of 15 to 30 gratings were angularly multiplexed in a volume of the photopolymer layers with different thickness at a spatial frequency of 1500 lines/mm. Since the photopolymer is a saturable material, an exposure scheduling method was used to exploit the entire dynamic range of the material and allow equal strength gratings to be recorded. From this investigation the photopolymer layer’s M/# was determined with regard to the recording geometry used. The temporal stability …

Holographic Recording Of Patterns In Thin Film Acrylamide-Based Photopolymer, Izabela Naydenova, Kotakonda Pavani, Emilia Mihaylova, Katia Loudmer, Suzanne Martin, Vincent Toal

Conference Papers

A study of the light induced surface relief modulation in thin photopolymer layers is reported. Due to the nature of the photopolymer used no additional post-processing is required after holographic recording. An investigation of the dependence of the amplitude of the photoinduced relief modulation on different parameters of recording such as spatial frequency, intensity of the beams and times of exposure has been carried out. The surface relief modulation is characterized by white light interferometry. Photopolymer layer thickness ranges from 1-5m. A model of the mechanism of surface relief formation is proposed on the basis of the measured dependencies. A …

Investigation Of Polymerization Rate In An Acrylamide-Based Photopolymer Using Raman Spectroscopy, Raghavendra Jallapuram, Izabela Naydenova, Hugh Byrne, Suzanne Martin, Robert Howard, Vincent Toal

Conference Papers

Diffusion models predict that polymerization and diffusion rates are the key factors that control the dynamics and the final properties of a holographic grating recorded in a photopolymerizable material. Diffusion rates during the initial phase of holographic recording have already been studied and reported. We now report the investigation of the polymerization rate in an acrylamide-based photopolymer using Raman spectroscopy. The polymerization rate constant was estimated by monitoring the intensity of the characteristic Raman peaks at 1284 cm-1 corresponding to the bending mode of CH vinyl bond in acrylamide and 1609 cm-1 corresponding to the carbon-carbon double bond (C=C) in …

On-Road Emissions In Asia Measured By Remote Sensing (Presentation), Donald H. Stedman, Gary A. Bishop

Fuel Efficiency Automobile Test Publications

No abstract provided.

Structure Property Relationships In Organic Conjugated Systems, Luke O'Neill, Patrick Lynch, Mary Mcnamara

Articles

A series of π conjugated oligomers were studied by absorption and photoluminescence spectroscopy. A linear relationship between the positioning of the absorption and photoluminescence maxima plotted against inverse conjugation length is observed. The relationships are in good agreement with the simple particle in a box method, one of the earliest descriptions of the properties of one-dimensional organic molecules. In addition to the electronic transition energies, it was observed that the Stokes shift also exhibited a well-defined relationship with increasing conjugation length, implying a correlation between the electron-vibrational coupling and chain length. This correlation is further examined using Raman spectroscopy, whereby …

Structural Property Relationships In Conjugated Polymers, Patrick Lynch, Luke O'Neill, J. Whelan, Mary Mcnamara, Hugh Byrne

Articles

The synthesis of a series of PPV derivative polymers by the Wittig-Horner reaction is described. The structure of each polymer is varied and the effects of these variations on the optical properties is explored. The effects of alkyloxy side chains is observed between the PPV derivatives Poly(-p-phenylvinylene-co-2,5-bis-octyloxy phenylvinylene.) PPV-OPV and Poly (para-2,5-bis-(n-octyloxy)-phenylvinylene) POPV. The phenyl units of the soluble PPV derivative POPV are replaced by alternate naphthyl units in the polymer Poly(2,5-bis(n-octyloxy)-1,4-phenylene vinylene-1,5-bis(n-octyloxy)-2,6-naphthylene vinylene) POPN-ONV and then fully by naphthyl units in Poly(2,6-bis-(n-octyloxy)-1,5-NaphthyleneVinylene) PONV. The addition of alkyloxy sidechains served to red shift the fluorescence emission as expected. The systematic …

Correlation Of Spectroscopic And Biochemical Assays Postionising Radiation Exposure In Human Skin Cell Analogues, Aidan Meade, Hugh Byrne, Fiona Lyng

Conference papers

Raman spectroscopy, as an evaluation of the products of ionising radiation exposure in biological systems, has been utilised mainly in the evaluation of the impact of exposure in tissue, cellular constituents and live animals. It has also been recently demonstrated that Raman spectroscopy can demonstrate key spectroscopic changes in the live cell associated with significant apoptotic and necrotic chemical damage. The present preliminary work utilises Raman spectroscopy at 514.5 nm to evaluate the results of exposure to -rays in HaCaT cells from a Co-60 therapy source, in tandem with other biological assays. The results demonstrate that a number of spectral …

Electroabsorption Studies Of Structurally Modified Fullerene Thin Films, Gerald Farrell, Gordon Chambers, Hugh Byrne

Conference papers

Ultraviolet (UV/Vis) and Electroabsorption (EA) spectroscopy is used to examine and differentiate between intermolecular and intra molecular excited state species in fullerene films. Charge Transfer (CT) states are identified at 2.4 eV and 2.7 eV and dipole moments are calculated. Thermal annealing of C60 films is monitored in situ using absorption spectroscopy and electroabsorption spectroscopy. Recorded spectra display both some temperature dependent and partially irreversible effects, indicating the occurrence of an annealing process. EA shows that the CT states associated with the transferring an electron from the HOMO of one molecule located at the (0,0,0) position to the LUMO of …

Use Of Raman Spectroscopy In The Investigation Of Debundling Of Single Walled Carbon Nanotubes, Elizabeth Gregan, Sinead Keogh, Theresa Hedderman, Gordon Chambers, Hugh Byrne

Conference papers

Samples of raw nanotubes are compared to those deposited from solutions to examine separation of nanotube bundles. Single wall nanotubes bundles produced by the arc-discharge and HiPco methods were solubilised in toluene, DMF and 1,2 dichloroethane. Resonant Raman spectroscopy was used to determine if debundling of the tubes sample occurred. The results showed some degree of debundling, best for the 1,2 dichloroethane solvent, which also shows long term solubility.

A Context-Dependent Model Of Proximity In Physically Situated Environments, John D. Kelleher, Geert-Jan M. Kruijff

Conference papers

The paper presents a computational model for a context-dependent analysis of a physical environment in terms of spatial proximity. The model provides a basis for grounding linguistic analyses of spatial expressions in visual perception. The model uses potential fields to model spatial proximity. It has been implemented, and when combined with a handcrafted grammar, is used to enable a conversational robot to carry out a situated dialogue with a human. The key concept in our approach is defining the region that is proximal to a landmark based on the spatial configuration of other objects in the scene. The model extends …

Nmr And Modulated Differential Scanning Calorimetry Of Adsorbed Poly(Methyl Acrylate) On Silica, Frank D. Blum, Burak Metin

Chemistry Faculty Research & Creative Works

The interaction between polymers and solid substrates can be studied by a variety of techniques. The results from different experiments can be affected by the nature of the polymer, surface, polymer-surface interactions and, also, the experiment. A great deal has been learned about the behavior of polymers at interfaces, but there is also much to be learned about the interactions and how they affect the physical properties of adsorbed polymers. In the present study, we report both deuterium nuclear magnetic resonance (NMR) and modulated differential scanning calorimetry (MDSC) of poly(methyl acrylate) (PMA) adsorbed on Cab-O-Sil silica. The focus of this …

Coupled Electrical And Magnetic Properties In (La,Sr)Feo3-Δ, X.-D. Zhou, Qingsheng Cai, Jinbo Yang, M. S. Kim, William B. Yelon, William Joseph James, Y.-W. Shin, B. J. Scarfino, Harlan U. Anderson

Materials Science and Engineering Faculty Research & Creative Works

This article is aimed at studying the temperature dependence oxygen nonstoichiometry, magnetic moments, Fe³⁺ fraction, Néel temperature and conductivity of (La,Sr)FeO_3-δ. It is found that the magnetic properties in La_0.60 Sr_0.40 Fe_3-δ is determined by Fe³⁺ and its concentration, and the conductance is resulted from Fe⁴⁺ ions, which act as electron holes. Both of magnetic and electrical properties were directly governed by oxygen nonstoichiometry (δ). when δ=0.2, the compound has maximum Fe³⁺, the saturation magnetic moments and Néel temperature are 3.8 µB and 410 °C, both at the highest level, …

Mcnair Research Journal

Georgia Southern University McNair Scholars Journal (Archived)

Full issue of the Georgia Southern University McNair Journal presented by the Ronald E. McNair Post-Baccalaureate Achievement Program at Georgia Southern University.

• The Acceptability of Aggressive Behaviors in Dating Relationships Kirsten Barnard; Dr. Janice Kennedy

• A Response to My Bank Teller: How Has a Nation of Immigrants Become So Anti-immigrant Angel Beal; Darin Van Tassell, PhD.

• Glucose Fermentation Profiles of Geographically Diverse Spiroplasma Bacteria David Bostick; Laura B. Regassa, PhD.

• An Analysis of the Relation Between High Discretionary Quarterly Revenue Accruals and Fraudulent Earnings Management Enforcement Actions Taken by the Sec Korey S. Castleberry; Timothy Cairney, PhD.

• How Has the …

  ---

  Go to article

Stability In Dynamical Polysystems, George Cazacu

LSU Doctoral Dissertations

A dynamical polysystem consists of a family of continuous dynamical systems, all acting on a given metric space. The first chapter of the present thesis shows a generalization of control systems via dynamical polysystems and establishes the equivalence of the two notions under certain lipschitz condition on the function defining the dynamics. The remaining chapters are focused on a basic theory of dynamical polysystems. Some topological properties of limit sets are described in Chapter 2. Chapters 3 and 4 provide characterizations for various notions of strong stability. Chapter 5 makes use of the theory of closed relations to study Lyapunov …

Fabrication Of Inverted Opal Zno Photonic Crystals By Atomic Layer Deposition, Michael Scharrer, Xiaohua Wu, Alexey Yamilov, Hui Cao, Robert P. H. Chang

Physics Faculty Research & Creative Works

We have fabricated three-dimensional optically active ZnO photonic crystals by infiltrating polystyrene opal templates using a low-temperature atomic layer deposition process. The polystyrene is removed by firing the samples at elevated temperatures, and reactive ion etching is used to remove the top layer of ZnO and expose the (111) photonic crystal surface. The resulting structures have high filling fractions, possess photonic band gaps in the near-UV to visible spectrum, and exhibit efficient photoluminescence.

Maintaining The Identity Of Dynamically Embodied Agents, Alan Martin, Gregory O'Hare, Brian Duffy, Bianca Schoen-Phelan, John Bradley

Conference papers

Virtual agents are traditionally constrained in their embod- iment, as they are restricted to one form of body. We propose allowing them to change their embodiment in order to expand their capabili- ties. This presents users with a number of di±culties in maintaining the identity of the agents, but these can be overcome by using identity cues, certain features that remain constant across embodiment forms. This pa- per outlines an experiment that examines these identity cues, and shows that they can be used to help address this identity problem.

Intentional Embodied Agents, Alan Martin, Gregory M.P. O'Hare, Brian R. Duffy, John F. Bradley, Bianca Schoen-Phelan

Conference papers

The notion of embodiment within a virtual environment and an intelligent agent could be intimately linked, in order to form a single Agent Chameleon. This paper presents an architecture for achieving this, while allowing agents freedom to chose an embodiment suitable to the task at hand..

The Amphere Algorithm: Area Masking With The Performance Equation, Bianca Schoen-Phelan, Gregory O'Hare, Brian Duffy, Alan Martin, John Bradley

Conference papers

This paper is concerned with the employment of an autonomous and intelligent agent within the context of a 3-dimensional virtual environment. As the agent is immersed within the virtual environment, it empowers the 3D world with mechanisms to adjust itself to the specific needs of its user. Therefore, the agent serves as a middle layer between user and the environment. The 3-dimensional environment thus evolved into an intelligent user interface. We track user’s motion within this environment and present an equation upon which the agent classifies the user’s performance. Based upon this performance value, the agent autonomously determines if the …

Bi-Directional Ontology Versioning Bov, Siyang Zhao, Brendan Tierney

Conference papers

his paper defines a new type of ontology versioning: Bi-directional Ontology Versioning: BOV. BOV provides bi-directional mappings and transformations between concepts in two ontology versions. BOV is identified by two levels mapping processes: linguistic mapping and structural mapping. BOV can satisfy the requirement of mapping in distributed environment.

Generating Estimates Of Classification Confidence For A Case-Based Spam Filter, Sarah Jane Delany, Padraig Cunningham, Donal Coyle, Anton Zamolotskikh

Conference papers

Producing estimates of classification confidence is surprisingly difficult. One might expect that classifiers that can produce numeric classification scores (e.g. k-Nearest Neighbour, Na¨ıve Bayes or Support Vector Machines) could readily produce confidence estimates based on thresholds. In fact, this proves not to be the case, probably because these are not probabilistic classifiers in the strict sense. The numeric scores coming from k-Nearest Neighbour, Na¨ıve Bayes and Support Vector Machine classifiers are not well correlated with classification confidence. In this paper we describe a case-based spam filtering application that would benefit significantly from an ability to attach confidence predictions to positive …

Macroinvertebrate Community Of Ecology Of Lowland, Subtropical Streams In Louisiana, Michael Douglas Kaller

LSU Doctoral Dissertations

Freshwater ecosystems, particularly streams and rivers, have been the subject of prodigious research. Unfortunately, in comparison to neighboring regions, the Gulf of Mexico coastal plain has not received as much attention. Therefore, I collected data on the macroinvertebrates of these streams to begin the understanding of the relationships between community structure and environmental characteristics. In contrast to the hypothesized ancestral streams of these macroinvertebrates, coastal plain streams are commonly devoid of rocks leaving only woody debris as usable hard substrates and are typically lower in dissolved oxygen. I examined habitat selection by colonization of woody debris with large and small …