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An Investigation on the Enhancement of Electromechanical Performance of Polymer Composites using Supercritical Carbon Dioxide for Electroactive Applications
Get PDFElectroactive polymers (EAPs), also known as artificial muscles, are a type of polymer which responds to an electric field with structural or mechanical changes. However, current plastic research and manufacturing sectors are still lacking the use of EAP’s for smart applications, due to their diverse thermal, mechanical and electrical behavioural changes depending on small variations in their processing conditions. Therefore, this research investigated the effects of novel supercritical carbon dioxide (scCO2) fluid assisted polymer processing techniques on the thermal, mechanical and electrical properties of EAPs. Semi-crystalline polymer Pebax and rubber elastomer Poly(styrene-ethylene-butylene-styrene) - SEBS was chosen as the base polymeric material; and in order to enhance the electroactive properties, graphene-graphene oxide were used as filler material. The research begins with preliminary investigations of the scCO2 processing of polymers at various critical pressures. This initial study indicated that both polymers resulted in increased microphase formation producing a more homogeneous co-polymer base material and decreased the mechanical properties due to the foaming effect. In order to enhance the electroactive properties of the base polymers, graphene-based filler materials at low concentrations (<2.5% wt.) were used, processed with and without scCO2. Clear enhancement with respect to mechanical properties and crystallisation kinetics were observed below 1% filler loading and additional information on the exfoliation and agglomeration effects were drawn. Finally, the effects of reprocessing scCO2 processed composites were investigated. Various crystallisation kinetics theories were used to understand the effects of scCO2 processing on the crystallisation process; these results were validated using X-ray diffraction through crystallite size calculation. An in-depth understanding of results obtained from thermal, mechanical and electrical behaviour were co-related. The thesis concludes that the use of scCO2 processing induced rearrangement of polymer chains into favourable configurations resulting in exfoliation of filler particles with improved homogeneity, mechanical and electrical properties. Bending capabilities were evaluated by sulfonation of the manufactured SEBS graphene oxide composites. The sSEBS graphene oxide composites processed with scCO2 demonstrated a maximum bending actuation of 27 degrees
MaaS: An application-centric, dynamic, end-to-end QoS framework utilizing SDN Federation
Get PDFInternet is a collection of many distributed autonomous network domains. These domains deploy only limited control services amongst each other, most notably Border Gateway Protocol (BGP), primarily due to understandable security, integrity and management reasons. This construct can thus be attributed to hindering in development of powerful inter-domain control services that perform end-to-end network service provisioning such as QoS. The benefits though of having a dynamic end-to-end Quality of Service (QoS) provisioning service for multi-domain networks are in tuning to real-time application resource requirements. The need for such an application-centric QoS framework is now more than ever as Internet traffic is continuously increasing and ability to provision network service in real-time at user application level would result in efficiency saving on under and overprovisioning. Existing end-to-end QoS frameworks such as IntServ and Multi-protocol Label Switching (MPLS) lack dynamicity primarily attributed to distributed domain control-plane apart from also being hindered in deployment due to lack of activity in inter-domain control-plane as discussed previously. This Thesis proposes solution in form of a dynamic application-centric QoS framework utilizing Software Defined Networking (SDN) breakthrough. SDN controller is proposal of a centralized and thus dynamic domain control-plane, while collaboration between such per-domain control-planes referred to as SDN Federation enables ground for securing and enriching inter-domain control-plane as well, potentially improving upon the dynamicity limitations of legacy frameworks. The proposed framework named MPLS-as-a-Service (MaaS), is an implementation of prominent Internet Traffic Engineering (TE) framework - MPLS in SDN controller. The resultant SDN-MPLS control-plane made dynamic by SDN (Federation) enables network operators to swiftly provision QoS Label Switched Path (LSP)s and offer MPLS as a service model compared to present day long-term contracts. The complete design of MaaS is provided in the thesis, while the design of supporting underlying SDN-IP-BGP control-plane is also considered. This highlights a stand-out feature of the proposal as current research direction in end-to-end QoS provisioning is from outside domain control-plane orchestrated by third-party vendors, while we propose a native and in-network solution courtesy of this SDN-MPLS-IP-BGP control-plane. An easy to provision multi-domain network testbed is also created through virtual devices. MaaS and the underlying SDN control-plane is developed as well as demonstrated on this testbed. Apart from the dynamic inter-domain QoS property, MaaS is equipped with more adaptive error-handling through a service renegotiation mechanism and scalability enhancement measures over legacy MPLS which as well are demonstrated on the testbed
Modelo de Ganho de Canal em Comunicações Moleculares para um Sistema Circulatório de Gestantes
Get PDFGestation is a period in which the body and the immune system of women undergo progressive changes, resulting in hemodynamic changes characteristic of this period. This phenomenos can affect circulatory molecular communication systems with changes in the propagation of signals in arteries and artery trees. In this paper we present a mathematical model that allows the calculation of the blood flow values during the gestational period, taking into account the new parameters obtained by the changes that occurred during pregnancy. We perform an analysis of the molecular channel gain, and we observed that the blood flow can increase 85,58% for pregnant women and the gain of the channel can get to a total of 2dB
Advocacy and the Magdalene Laundries: towards a psychology of social change
Get PDFThis article will describe how a project documenting inter- views with survivors of Ireland’s Magdalene Laundries explores the relationship between psychology and advocacy. The Waterford Memories Project focuses on documenting survivor narratives both for subsequent qualitative analysis and a publicly accessible record of the women’s experiences about events, which remain silenced and hidden in Irish society. The process of documenting the women’s narratives is, in itself, an action toward social change because it chal- lenges the lacuna of information and data available from the Irish Government and Religious Orders. The archives of the Laundries are heavily restricted, and the women’s voices sup- pressed, which has implications for the ability of survivors to integrate their experiences of violence into personal narra- tives. In this project, an action-approached focus to psycho- logical research with the survivors of the Magdalene Laundries provides strong evidence for the suitability of applying psychological methods to social and moral issues
Using Social Media to Enable Staff Knowledge Sharing in Higher Education Institutions
Get PDFHigher education institutions (HEIs) are knowledge intensive environments by nature.
However, the management of organisational knowledge and the promotion of staff
knowledge sharing is largely neglected in these institutions. This study examines how
enterprise social networks can enable staff knowledge sharing in communities of practice in
that context. The study is framed as an Action Research project, covering three cycles over a
12 month period. A conceptual model was developed for empirical testing and data was
collected through focus groups and interviews, supplemented by reflective journaling and
content analysis. The findings support the conceptual model and provide insight into the
antecedents necessary for the creation of an enterprise social network enabled knowledge
sharing environment, the motivators for and barriers to participation, and the perceived
organisational and individual benefits of increased staff knowledge sharing activity. The
findings indicate that the barriers to participation are influenced by the prevalent organisation
structure and culture, and a divide between faculty and other staff. However, individual
benefits that accrue from participation may influence greater participation, and organisational
benefits that accrue may influence organisational strategies that drive change in structure and
culture to promote the development of the knowledge sharing environment. A number of
findings have practical implications for the management of higher education institutions, such
as the evidence of a divide between faculty and other staff, and the perceived existence of an
organisational culture that inhibits staff communication, interaction and collaboration. In
general, the study findings provide an opportunity for educationalists to better understand
the scope and impact of employing social media platforms for knowledge sharing. This study
adds to the growing body of work on organisational implementations of social media, and
should be of interest to practitioners and researchers undertaking similar projects
Music from other Worlds A portfolio of original compositions with a critical analysis Volume 2
Get PDFMATERIALS CHARACTERISATION OF CRYSTALLINE BECLOMETHASONE DIPROPIONATE: IMPACT OF MANUFACTURING CONDITIONS ON PHYSICOCHEMICAL PROPERTIES
Get PDFActive pharmaceutical ingredients in dry powder inhaler (DPI) formulations need to have well-defined material properties. These can be influenced by the choice of processing parameters. The impact of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 1-pentanol and acetone on the crystallisation of beclomethasone dipropionate (BDP), an anti-inflammatory agent, was studied using infrared spectroscopy, X-ray powder diffraction, thermal analysis, gas chromatography with mass spectrometry, scanning electron microscopy and atomic force microscopy. Crystallisation from methanol, 1-butanol and 1-pentanol resulted in particulate BDP with a predominantly anhydrous character. In contrast, BDP solvates were formed using ethanol, 1-propanol, 2-propanol and acetone. The physical properties of the solvates were found to depending on the solvent used.
Single crystal X-ray diffraction and solid state NMR confirmed the inclusion of ethanol, 1-propanol, 2-propanol and acetone within the crystalline BDP host. Based on NMR titration, DOSY, thermal analysis and XRD, the intermolecular interactions leading to the preferred formation of either solvated or anhydrous BDP from solution were analysed. The same combination of techniques can be potentially used to predict the formation of solvated compounds in general by assessing the forces acting between the host and guest molecules and analysing their impact on solvate formation and stability.
The size, shape and surface characteristics of the crystalline particles were found to be influenced by the choice of solvent in a reproducible way. These properties were also found to translate to the anhydrous products prepared from the solvates through controlled desolvation. Thus, anhydrous BDP with defined surface properties were prepared. AFM was used to evaluate the adhesive and cohesive forces between lactose, a commonly used carrier material in DPI formulations, and anhydrous BDP prepared from the BDP ethanol, 1-propanol and 2-propanol solvates.
The interparticulate forces in a DPI formulation depend to a large part on the surface roughness of the drug particles and the carrier material. It was demonstrated that the surface roughness of anhydrous BDP can be controlled through the manufacturing process. This is an important step towards the targeted preparation of well-defined formulations which have the potential to be tailored to specific patient needs
An Evaluation of Phase 2 of the GAA Healthy Club Project
Get PDFIntroduction: The GAA, in partnership with the HSE, have developed the ‘GAA Healthy Club’ project. A pilot phase of the project was evaluated (Lane et al., 2015) and findings supported the delivery of health promotion through the GAA club setting. In Phase 2, the overall objectives of the evaluation were; (i) to assess the impact of healthy club initiatives on the health of individuals and communities, and (ii) to assess the impact of the project on the daily workings of the GAA club unit. Methods: 60 clubs took part in Phase 2 of the ‘GAA Healthy Club’ project along with 27 control clubs. Mixed methods were used to gather data. Clubs completed a Healthy Club Questionnaire adapted from an index developed by Kokko et al., (2009) at baseline and at the end of Phase 2. The Healthy Club Index indicates the health promotion orientation of a sports club and includes a number of sub-indices such as Policy, Ideology, Practice and Environment. Clubs also self-reported on their overall activity at the end of the 18 month project. Finally, in order to assess objective I a focused evaluation was carried out on three initiatives in the areas of physical activity (PA), healthy eating and community development. Questionnaires, Interviews and FGDs were used to evaluate these initiatives. Results: At follow up, intervention clubs showed significant improvements in overall health promotion orientation (PRE: 18.24, POST: 25.40), while control clubs showed little change (PRE: 22.28, POST: 22.25). Significant improvements were also evident across the subindices. Overall, it was notable that a sense of clarity and purpose existed in clubs, but did so within resistance, which clubs actively worked to overcome. The PA initiative included the delivery of the Men on the Move programme with participants reporting an average 2kg weight loss and improvement in cardiorespiratory fitness that was maintained up to 26 weeks. Waist circumference dropped by 3-4 cm and again this was maintained up to 26 weeks. Of the 3 clubs who engaged in the healthy eating evaluation, 2 had adopted healthy eating guidelines and the third club was in the process of developing their guidelines. Across all clubs in the evaluation, 52% had partially or fully implemented these same guidelines. Conclusion(s): The GAA club displays an affiliation and commitment to health promotion that identifies it as an ideal setting for delivering health interventions. Specialist agencies should be encouraged and supported to partner with these sports clubs to ensure the delivery of evidence based, effective initiatives
The Experience and Performance of ‘Appropriate Femininity’ by Teenage Girls in Contemporary Ireland: Collision of Online and Offline Selves
Get PDFThis qualitative research project explored a two-folded issue: how teenage girls experienced what it meant to be a girl in contemporary Ireland while being subjected by the global and local discourses of neoliberalism and postfeminism. Literature highlights that dominant media discourses address contemporary young girls as the subject of capacity (‘can-do’ femininity): able and capable of exercising their rights and feminine power. However, throughout media advertising, female power is continuously presented as primarily deriving from the possession of a young fit sexual female body. On the other hand, Irish cultural scripts of femininity – chaste, caring and family orientated – inform young girls about how to function in Irish society. To date, there have been few published studies that explored the experiences of teenage girls’ lives in Ireland. However, there is a gap in knowledge in understanding how teenage girls construct their online as well as offline female identities in contemporary Ireland. Thus, the question arises: how do teenage girls in Ireland navigate their online and offline identities when they are subjectified by local and global ethics of self-realisation? In-depth semi-structured qualitative consecutive interviews were employed (three times) to collect data from a sample of Transition Year (15-17 year-olds) teenage girls. The interviews followed a carnal hermeneutic approach to account for embodied teenage girls’ experiences. Data were thematically analysed following an interpretivist paradigm and informed by a Foucauldian and feminist theoretical standpoint. The research findings indicate that on social media the patriarchal power transforms itself through the positive affirmations of ‘Like’, resulting in a disembodied form of power. While teenage girls employ the language of ‘can-do’ femininity when constructing their social media identity, that identity is tightly policed to contain it within the stereotypical boundaries of femininity
Tool Condition Performance Monitoring, Evaluation and Analysis in a Modern Industrial Precision Manufacturing Environment
Get PDFThis thesis presents research and evaluation of the various phenomena that potentially contain worthwhile information in the performance of machining operations. In particular what these phenomena can tell a computer-controlled machine, or the machine operator, about the degree of tool wear being experienced during the operation. Tool wear is an unavoidable element of machining operations and a variety of approaches have been investigated and implemented to delay the onset of wear, e.g. cutting fluid, tool coatings. However, there is currently no reliable system whereby tool wear itself can be monitored during the cutting operation; this information is only available at the end of the operation, through tool or work piece inspection and interrogation. It was the intention of this research to determine which of the machining phenomena, or fusions of these phenomena, is likely to provide the most worthwhile information for such monitoring. All the data gathered during this research and presented in this thesis was from machines working in a commercial environment, carrying out typical live production cutting operations, thus providing data that could be worthwhile for modern industry. While this work started as the author’s own research into process monitoring of the machining process, it expanded into an FP7 funded project with the acronym “REALISM” Realism project (2015), with the author’s organisation Schivo and WIT as the Lead Partners. This pan-European project formally commenced in Jan 2014 and had a 2-year duration, concluding at the end of 2015. REALISM’s aim was to build and test a tool condition monitoring system and, based on that, to lay the groundwork for the future goal of optimizing tool usage and the tool change decision