Now showing 1 - 10 of 621
  • Publication
    Extension of semi-analytical approach to determine natural frequencies and mode shapes of multi-span orthotropic bridge deck
    This paper extends a single equation, semi-analytical approach for three-span bridges to multispan ones for the rapid and precise determination of natural frequencies and natural mode shapes of an orthotropic, multi-span plate. This method can be used to study the dynamic interaction between bridges and vehicles. It is based on the modal superposition method taking into account intermodal coupling to determine natural frequencies and mode shapes of a bridge deck. In this paper, a four- and a five-span orthotropic roadway bridge decks are compared in the first 10 modes with a finite element method analysis using ANSYS software. This simplified implementation matches numerical modeling within 2% in all cases. The paper verifies that applicability of single formula approach as a simpler alternative to finite element modeling.
  • Publication
    The Waterford mental health survey
    (University College Dublin. School of Psychology; Health Services Executive, 2015-02) ; ; ;
    The primary objective of the Waterford Mental Health Survey was to document the prevalence of co-morbid personality disorders in a sample of inpatients and outpatients attending the HSE mental health service in Waterford and outline the implications of this for service development. Between July 2011 and June 2014, 100 inpatients and 99 outpatients were evaluated with the Structured Clinical Interviews for DSM-IV axis I and II disorders, the Childhood Trauma Questionnaire, the Global Assessment of Functioning rating scale, the SCORE family assessment instrument, the Camberwell Assessment of Need Short Appraisal Schedule, and the Readiness for Psychotherapy Index. Participants were consenting, consecutive referrals who were not too unwell to engage with the study. The sample interviewed was probably slightly higher functioning than all cases attending the service. With regard to the primary objective of the study, we found that 98.4% of cases had DSM-IV axis I psychiatric disorders and 39.3% of these had comorbid axis II personality disorders. Between approximately a half and three-quarters of cases with personality disorders had comorbid anxiety, depressive or alcohol and substance use disorders. Compared to those without personality disorders, cases with personality disorders had experienced more child maltreatment; had poorer personal and family functioning and more severe presenting problems; and reported greater unmet service needs and motivation for psychotherapy. In terms of service development, approximately 2 out of 5 patients attending the public mental health services in Waterford require specialist psychological therapy for personality disorders which addresses low levels of personal and family functioning and past history ofchild maltreatment. Specialist psychological therapies include dialectical behaviour therapy (Linehan, 1993. 2014), schema therapy (Young et al., 2007), cognitive behaviour therapy (Beck et al., 2004) and brief psychodynamic psychotherapy such as mentalization-based treatment (Bateman & Fonagy, 2006; Clarkin et al., 2010). A review of psychology staffing levels is required to determine the number of psychologists required to provide this type of service in line with recommendations in the national mental health policy - Vision for Change (Department of Health & Children, 2006) - and the HPSI Psychology briefing paper for the HSE mental health division (Heads of Psychology Services Ireland, 2014). Intensive initial staff training and ongoing supervision are required for psychologists to provide these specialist evidence-based interventions. 
  • Publication
    Early occupation at Ille Cave, New Ibajay, El Nido, Palawan, Philippines: Report on the 2005 excavation season
    Excavations were carried out at the East and West Mouths of the rockshelter at Ille Cave, New Ibajay, Palawan, a site comprising a later prehistoric/palaeohistoric cemetery overlying a midden of shell and animal bones, and lower levels with Palaeolithic occupation materials. The 2005 project extend ed the previously investigated trenches (Szabó et al. 2004; Paz & Ronquill o 2004; Paz 2004), with the aims of: 1) exploring the extent and nature of the later prehistoric cemetery and underlying shell midden horizons , 2) exposing deep burning deposits discovered during 2004 recording of a looter’s pit, and 3) collecting further samples for dating and palaeoenvironmental analyses from all horizons to characterise use of the cave and the nature of the surrounding landscape from historic times back into the earl y Holocene. Additional test trenches were investigated to the south of t he cave platform and within the East Mouth chamber, to explor e platform history and a gradient exposed in rock shelter deposits during the 2004 excavations. The East Mouth chamber trench also provided an ‘in - cave’ setting, which was anticipated to reveal d ifferent remains and/or preservation environments to the rock shelter are
  • Publication
    Large-area sub-micron structured surfaces using micro injection moulding templates of nanoporous anodized Aluminum Oxide
    (Research Publishing Services, 2012) ; ; ;
    This study demonstrates a mass production method using nanoporous Anodized Aluminum Oxide (AAO) templates as mould insert tools that are used to structure large area polymer surfaces by a micro injection moulding process. SEM and water contact angle measurements served to evaluate the effect of nanostructures on surface properties. Human umbilical vein endothelial cells were cultured on nano-structured and ultra-smooth surfaces of polymer parts. Experimental results indicated that nano-pillar features sized from ~100nm to 250nm were easily replicated on these same polymer surfaces. The contact angles varied from 3o to 9o. The nanoporous AAO templates were able to retain their pore integrity very well for ~80 injection moulding cycles: this suggests they they could be a potential mould tool for large area patterning of polymer surfaces. The endothelial cell culture analysis indicates that cell growth was not significantly affected by nano-topography compared to the smooth surfaces (baseline RA ~6nm) and both surfaces had equally good cell adhesion.
  • Publication
    Clumped C-O isotope temperature constraints for carbonate precipitation associated with the Irish-type Lisheen and Navan Zn-Pb orebodies
    Mineral C-O isotope values are controlled by crystallization temperature and the isotopic composition of the fluid.
  • Publication
    Production of medicated bedding straw: challenges and perspectives
    Previous bacteriological findings have reported that animal disease outbreaks are associated with the quality of the animal environment. Animal bedding straw is a good source of bacteria and fungi, typically contaminated with (mycelia) yeasts and filamentous fungi species such as Aspergillus, Fusarium, Alternaria, Cladosporium, Epicoccum, Penicillium, Verticillium and Enterobacteria. The objective of this work was to assess the efficacy of different technologies on the production of medicated bedding straw. Four critical control points of an industrial straw disinfection processing line were identified. The levels of fungi and bacteria present in the straw during an industrially applied mechanical – chemical process were quantified. The plate counting revealed that propionic acid and formaldehyde chemicals reduced the microbial levels from the raw material and that they were more efficient on moulds than on bacteria. The potential use of ozone gas as an alternative greener technology to the current liquid chemical treatments was also evaluated. Trials conducted on ozone treatments (flow rates: 0.031, 0.125, 0.5 L/min, concentrations: 36, 99, 150 μg/mL, treatment time: 0, 5, 15, 30 mins, and residual times of 0 to 18 hrs) indicated that ozone successfully reduces the microbial counts and the fungi levels by more than 1.5 logs (cfu/g).
  • Publication
    The eSMART Project: real time symptom management in the oncology setting
    In 2013 European Union funding was awarded for the eSMART (Electronic Symptom Management Using the ASyMS Remote Technology) study, to evaluate the use of mobile phone technology for management of chemotherapy symptoms in a two-part, pragmatic, RCT across fourteen European clinical sites, including four in the Republic of Ireland (ROI).
  • Publication
    Micromechanical Study of Strength and Toughness of Advanced Ceramics
    Numerical investigations using the finite volume (FV) method were conducted to examine the effect of microstructure and mi- crostructural properties on the fracture strength of advanced ceramics with industrial applications. Statistically representative microstructural volumes were created using a diffuse-interface model using OpenFOAM-1.6-ext. Crack initiation and growth was modeled using a recently developed arbitrary crack propagation model. It was found that by varying the Young's modulus of the second phase material, a significant change in the maximum failure load was observed. It was also shown that there exists an opti- mum Young's modulus for which a maximum failure load will be reached. A number of microstructures with a varying percentage second phase material were investigated in this study. Results indicate that for a given set of material and cohesive parameters the maximum failure load was insensitive to the percentage second phase material. This study highlights the role that microstructure adconstituent properties of brittle ceramics have on influencing the fracture strength of such material. With this in mind, a para- metric study was undertaken to examine the competition between crack deflection and crack penetration at the interface between two materials. It was found that appropriate choice of interface strength and toughness as well as second phase material compliance was required in order to promote an overall strength and toughness increase through crack deflection and bridging. Such numerical modeling is essential in order to gain a greater understanding into the structure-property relationship that exists for such advanced ceramics.
  • Publication
    Data-Requirements Specification to Support BIM-Based HVAC-Definitions in Modelica
    Recent developments in Building Information Model (BIM) capable software are leading to increased interoperability among heterogeneous tools. The results are representing greater levels of data available for all stakeholders involved in the building industry. The increasing range of data within BIMs enables the reuse of data for downstream applications such as Building Energy Performance Simulation (BEPS). Current BEPS tools work well in many modeling scenarios, but fail to support innovative and flexible model configurations due to existing tool limitations. Modelica is an object-oriented, equation-based programming language used for detailed dynamic simulation purposes across different industries. The use of Modelica in the building industry is increasing and it is a promising and flexible tool to provide modeling solutions addressing the upcoming challenges in the building industry and beyond. This paper illustrates a method of using BIM based information as the primary data source for a flexible simulation application. It includes an implementation for a defined generic use case.
  • Publication
    How did Immigrants fare in the Irish Labour Market over the Great Recession?
    (University College Dublin. Geary Institute for Public Policy, 2015-07) ; ; ;
    Much research has been undertaken to study the effects of the Great Recession on overall labour market dynamics, but less is known about the impact on immigrants and how it has evolved over the business cycle. Understanding how immigrants were affected is particularly important for Ireland given the important role migrants play in the labour market. This paper attempts to fill this gap by identifying the labour market impact of the Great Recession on immigrants compared to natives and how this relationship has evolved since the downturn. In particular, we compare both groups’ likelihood of being employed and their risk of unemployment pre (2006), at the start of (2008) and during the depth of the employment crisis (2010 and 2012), and as the economy begun to recover (2014). In our analyses, we separately identify the impact of the recession on immigrants who have gained Irish citizenship through naturalisation, from those that retained their country of birth nationality. The main findings of the paper are twofold: i) The employment penalty suffered by immigrant workers, relative to native workers, increased significantly over the Irish recession and subsequent recovery. Differences in labour market outcomes between immigrants and natives were accentuated by the recession, when the employment penalty was the highest. The penalty narrowed in the recovery, although it remains higher than before the crisis; ii) The more recent evolution of the employment penalty appears to be related to a composition effect, as many refugee immigrants with weak labour market attachment became naturalised citizens during the recession. This suggests that the difficulties that some immigrants experience in the labour market would be under-estimated without taking due account of naturalisation processes, as is done in this paper for the first time in Ireland.