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Social Partnership and its Continuities
Get PDFSocial partnership has long been pronounced ‘dead’ and buried, lamented by few. But thirty years on from the watershed Programme for National Recovery of 1987, the underlying influence of the 22-year construct is stronger than it might seem. How pay formation in the private and public sectors works today; how management-union disputes are resolved; how employers and trade unions engage; and how the social partners manage key industrial relations issues, all suggest important continuities with the partnership era
Multiwavelength Observations of the Blazar BL Lacertae: A New Fast TeV Gamma-Ray Flare
Get PDFCombined with measurements made by very-long-baseline interferometry, the observations of fast TeV gamma-ray flares probe the structure and emission mechanism of blazar jets. However, only a handful of such flares have been detected to date, and only within the last few years have these flares been observed from lower-frequency-peaked BL Lac objects and flat-spectrum radio quasars. We report on a fast TeV gamma-ray flare from the blazar BL Lacertae observed by the Very Energetic Radiation Imaging Telescope Array System (VERITAS). with a rise time of ~2.3 hr and a decay time of ~36 min. The peak flux above 200 GeV is (4.2 ± 0.6) × 10−6 photon m−2 s−1 measured with a 4-minute-binned light curve, corresponding to ~180% of the flux that is observed from the Crab Nebula above the same energy threshold. Variability contemporaneous with the TeV gamma-ray flare was observed in GeV gamma-ray, X-ray, and optical flux, as well as in optical and radio polarization. Additionally, a possible moving emission feature with superluminal apparent velocity was identified in Very Long Baseline Array observations at 43 GHz, potentially passing the radio core of the jet around the time of the gamma-ray flare. We discuss the constraints on the size, Lorentz factor, and location of the emitting region of the flare, and the interpretations with several theoretical models that invoke relativistic plasma passing stationary shocks
Results Of WEBT, VLBA And RXTE Monitoring Of 3C 279 During 2006-2007
Get PDFContext. The quasar 3C 279 is among the most extreme blazars in terms of luminosity and variability of flux at all wavebands. Its variations in flux and polarization are quite complex and therefore require intensive monitoring observations at multiple wavebands to characterise and interpret the observed changes.
Aims. In this paper, we present radio-to-optical data taken by the WEBT, supplemented by our VLBA and RXTE observations, of 3C 279. Our goal is to use this extensive database to draw inferences regarding the physics of the relativistic jet.
Methods. We assemble multifrequency light curves with data from 30 ground-based observatories and the space-based instruments SWIFT (UVOT) and RXTE, along with linear polarization vs. time in the optical R band. In addition, we present a sequence of 22 images (with polarization vectors) at 43 GHz at resolution 0.15 milliarcsec, obtained with the VLBA. We analyse the light curves and polarization, as well as the spectral energy distributions at different epochs, corresponding to different brightness states.
Results. We find that the IR-optical-UV continuum spectrum of the variable component corresponds to a power law with a constant slope of -1.6, while in the 2.4–10 keV X-ray band it varies in slope from -1.1 to -1.6. The steepest X-ray spectrum occurs at a flux minimum. During a decline in flux from maximum in late 2006, the optical and 43 GHz core polarization vectors rotate by ~300°.
Conclusions. The continuum spectrum agrees with steady injection of relativistic electrons with a power-law energy distribution of slope -3.2 that is steepened to -4.2 at high energies by radiative losses. The X-ray emission at flux minimum comes most likely from a new component that starts in an upstream section of the jet where inverse Compton scattering of seed photons from outside the jet is important. The rotation of the polarization vector implies that the jet contains a helical magnetic field that extends ~20 pc past the 43 GHz core
Design and Implementation of a Micro-Inverter for Photovoltaic Applications
Get PDFThe objective of this work is to design and build a novel topology of a micro-inverter to directly convert DC power from a photovoltaic module to AC power. In the proposed micro-inverter, a structure with two power stages, which are DC/DC and then DC/AC converters, is used. A novel MPPT algorithm is implemented and evaluated in the DC/DC converter to optimize the solar panel energy production. The new method operates with an efficiency of 97.9%, which is a 1% improvement on the standard method, and a response time of
In this research, the following approach is taken. A literature review was conducted, to identify potential converter topologies. A topology for both converters was selected by comparison of performance through simulations. Maximum Power Point Tracking algorithms were also investigated, to select an appropriate control scheme. A design for two converters was then performed, leading to a prototype for experimental verificatio
University-Industry Collaboration: where to next?
Get PDFThe focus on the third mission of Universities is now some decades old. Boyer’s assertion that ‘theory simply cannot be divorced from practice’ and that any consideration of the role of faculty ‘must give new dignity and new status to the scholarship of application’ (Boyer, 1992) has been embodied in the almost ubiquitous linking of scholarship to real world issues and applications. There is a general acceptance that the knowledge and skills required in existing and emerging labour markets are often not well served by universities while at the same time there is a realisation that these skill requirements are rapidly changing (Muller, 2015). Collaboration between universities and industries is seen as essential to innovation sys-tems, with a number of researchers pointing to the impact of such collaboration on both the company’s ability to innovate and the generation of economic value within the country and the region. In Ireland a plethora of documents and a range of agencies purport to support and incentivise various forms of engage-ment interactions (Department of Education and Skills, 2017, 2016, 2015). Despite the significant apparent importance placed on university enterprise interactions, concrete measures of impact are severely lacking. Focus at a government agency level tends to be on the (relatively few) impact measures associated with technology transfer activity (Knowledge Transfer Ireland) while the myriad of more common interactions such work-placement opportunities for students, industry-based project activity, site visits, cultural and community interactions, subject matter expert seminars and customised and practice-based learning for those in the workplace tend not to attract as much attention. This full range of possible interactions has been the focus of the work of the CIT Extended Campus – a codification of interactions and an engagement mapping exercise provide a valuable perspective on the potential of collaboration across the academic-industry divide. It is recognised that the motivation and ability to collaborate changes with company size, sector and culture. Geography impacts on collaboration with many companies in collaboration with neighbouring universities, however the quality of the university is also a factor (Laursen, Reichstein, & Salter, 2011) (Fitjar & Gjelsvik, 2018). The factors that influence the scale and scope of engagement within a university differ from those which impact from the business perspective and while ‘the cultural divide between universities and industry runs deep’, effective measures can make a lasting difference (Science | Business Innovation Board, 2012). According to the Central Statistics Office over 99% of enterprises in Ireland are SMEs. While Cork Institute of Technology has worked to support interactions with all sectors and sizes of industry partners over many years it is still not clear that local industry has a knowledge of the possibilities and benefits of engaging. Using the initial results of the State of University-Business Cooperation study (Science to Business Mark-ing Research Centre, 2017) as a framework and question guide, a brief review of the motivators and barriers as experienced by small and medium enterprises is conducted and the findings provide some direction for future efforts
Drivers of Early Technology Sector Development in Ireland
Get PDFThis paper explores the origins of the electronics and software sector, now called the Information Communications and Technology (ICT) Sector in the Republic of Ireland and its subsequent development from 1960 to 2010 inclusive. The research sought to identify key developments that influenced the emergence of the sector. For the purposes of this study, the ICT sector is defined as the foreign-owned and indigenous firms actively involved in the production, design and/or servicing of hardware and software electronic products within the Republic of Ireland. Empirical evidence in the form of 15 semi-structured interviews was analysed and validated by three respondents as well as one external ICT expert. Two key drivers found in the data were the development of a capable managerial cohort and a spinoff mechanism
Identification and Characterisation of Novel Phages of Pectobacterium and Erwinia
Get PDFLosses in crop yields due to disease need to be reduced to meet increasing global food demands associated with growth in the human population. There is a well-recognised need to develop new environmentally-friendly control strategies to combat bacterial crop diseases. There are several crop diseases for which no effective bactericidal agents are currently available, such as potato blackleg and soft rot disease caused by Pectobacterium atrosepticum and other members of soft rot Enterobacteriaceae (Czajkowski et al., 2011). Furthermore, current control measures involving the use of traditional chemicals or antibiotics are losing their efficacy due to the natural development of bacterial resistance to these agents, as seen for fire blight of the pear and apple tree caused by Erwinia amylovora (de León Door et al., 2013; Mayerhofer et al., 2009; Ordax et al., 2006; Russo et al., 2008). Bacteriophages (phage), the viruses of bacteria, have received increased research interest in recent years as an environmentally friendly means of controlling bacterial diseases. However, not all phages possess the features that would enable them to be effective bactericidal agents. To this end, this thesis provides a detailed study of phages that infect Pectobacterium atrosepticum and Erwinia amylovora. The knowledge gained in the execution of this PhD thesis contributes to the pool knowledge about the lifestyles of the phages examined thus enabling a more informed choice with regard to the selection of suitable phages for biocontrol applications for the relevant phytopathogens
Examining the Potential of Design Thinking for Marketing Students in the Context of Workplace Learning and Performance Challenges
Get PDFDesign thinking, which initially emerged in the 1980s, has notably been recently receiving increased attention, particularly in business communities, as a process that enables rapid, innovative, and user-centric problem solving (Lockwood, 2010). As the forthcoming generations of marketing graduates enter this ‘Consumer Age’, they will be forced to think innovatively and empathetically in order to adjust to constant and rapid changes in our environment (Hanttu, 2013). Design thinking equips modern marketers with the opportunity to become consumercentric and effectively generate innovative solutions on a constant basis to complex challenges that exists (Mohr, 2015).
While the concept is gaining increasing hold amongst practitioners, surprisingly little academic attention has been devoted to applications of Design Thinking specifically in Marketing education settings, though the methodology’s strong emphasis on obtaining a deep understanding of the user would seem to connect with the principles of marketing (Glen et al., 2014). Notably, research has mainly been focused on business environments, leaving a gap where empirical research of Design Thinking specific to the Marketing student is needed. Thus the research question that I address in this study looks to determine:
“What potential can Design Thinking offer Marketing students in meeting workplace learning and performance challenges?
The research design is itself based on the principles of design thinking thus applies the iterative, cyclical and human-centred nature of the process, predominantly relying on frequent engagement and interactions with the marketing student to aid in addressing the research question. This thesis contributes to the area of Marketing education by offering insight into the Marketing students’ unarticulated issues and needs in relation to the Marketing curriculum, and in addition explores the most sought after requirements by today’s Marketing industry employees. This study also offers recommendations for the development of a collaborative and engaging toolkit that can support a Marketing students’ creative and solution-orientated thinking
The Impact of Entrepreneurship Education on Graduate Employability: A Cross Country Comparison
Get PDFThis thesis identifies and addresses a major gap in Entrepreneurship Education (EE) research. Specifically, it focuses on the entrepreneurial skills and attitudes embedded in employability skills. It tests the widely accepted assertion that employers desire more well-rounded graduates who possess entrepreneurial skills. Pittaway and Cope (2007) highlight an absence of evidence in the literature establishing a link between EE and employability skills.
It is the intersection of EE and graduate employability that provides the context for this study. This study examines the knowledge, skills and attitudes resulting from education and, in particular, from EE and ascertains the extent to which educators, employers and students value employability skills, with a focus on entrepreneurial skills. The core objectives of this study are to establish which employability and in particular, entrepreneurial skills are deemed most desirable for graduates to make them employable, who is responsible and is there agreement amongst stakeholders as to the employability skills most valued in an Irish context. This thesis further contributes a cross-country comparison between the impacts of EE and graduate employability viewpoints between Ireland and Croatia and provides points of similarity as well as differences.
To provide a multi-perspective viewpoint, three sampling frames were chosen. The first sample frame comprised of recruitment professionals in Irish organisations who actively employ graduates. The second sample frame was limited to lecturers with experience in EE modules. The third sampling frame comprised senior-level students who had received some level of EE during their studies within Cork Institute of Technology, a large HEI located in the Republic of Ireland. Survey data in the form of questionnaires were gathered and analysed from each sampling frame. The results indicate that a relationship exists between educators and employers’ viewpoints however; students differed in their attitudes towards employability and entrepreneurial skills to that of educators and employers
Aerodynamic Design and Analysis of a Large-Scale Stall-Regulated H-Type Vertical Axis Wind Turbine for an Offshire Floating Installation
Get PDFWind energy has witnessed a consistent expansion over the past decade, especially with the move to offshore installation. There is an increasing need to further exploit superior offshore wind resources, which is pushing multi-megawatt wind turbines into deeper water locations where the current popular horizontal axis wind turbine configuration is not entirely suitable. In particular, there has been a renewed interest in the vertical axis wind turbine (VAWT) configuration due to its inherent design attributes for an offshore floating application and also its potential to provide a significant reduction in the system cost of energy. However, challenges still remain as the current offshore VAWT technology status lags greatly behind its horizontal axis counterpart. This research concentrates on the aerodynamic design and simulation of a large-scale stall-regulated H-type VAWT for this offshore application. At this large-scale, the VAWT\u27s blades will operate at high Reynolds numbers and encounter dynamic stall at low tip-speed ratios (TSRs). A validated computational fluid dynamics (CFD) method was developed to stimulate the unsteady aerodynamics experienced by a VAWT at this scale. The performance of Unsteady Reynolds-Averaged Navier-Stokes (URANS) and Detached Eddy Simulation (DES) modelling methods are compared in simulating the aerodynamics of an isolated NACA 0018 blade experiencing Darrieus pitching motion. The URANS turbulence models employed were the Spalart-Allmaras (S-A) model and the k-w SST model. Investigations were conducted to ensure satisfactory independency of the solution for both spatial and temporal discretisations, respectively. A quantitative assessment identified the S-A model as the most applicable for a VAWT design study, as it showed the most desirable compromise between model fidelity and computational requirement. A qualitative analysis revealed that the thick VAWT blade creates a dynamic stall vortex topology highly concentrated at the trailing edge region. Increasing the Reynolds number showed to be beneficial to the blade\u27s aerodynamic performance as a higher maximum tangential force coefficient is attained, owing to the delay in flow separation to much higher angles of attack. Increasing the freestream turbulence intensity similarly delayed the dynamic stall onset and the blade flow reattachment feature following the dynamic stall event. Investigation of the blade mounting point position during dynamic stall showed the chordwise range x/c=0.2-0.3 resulted in the lowest blade pitching moments. A low-order model (LOM) was developed to provide a rapid calculation of the VAWT performance and improve the design process efficiency. The LOM incorporates different sub-models for various aerodynamic effects, including a Beddoes-Leishman (B-L) dynamic stall model to account for unsteady dynamic stall effects. To provide enhanced numerical efficiency and stability, an iterative time-advancement scheme with adaptive under-relaxation has been integrated into the developed LOM. A comparative study of the LOM an the CFD model was undertaken to assess predictive accuracy with actual VAWT aerodynamic blade force experimental data and power coefficient measurements. The LOM showed good agreement with the CFD model and the measurements with a low computational cost requirement. The CFD results identified that as the TSR was increased, the rotating tower downwind wake region became increasingly more skewed and more influential over a wider range of downwind azimuthal angles. The 2D CFD model captured the qualitative shape of the VAWT performance curve but greatly overestimated efficiency at all the simulated TSRs. An approach for computing the B-L dynamic stall model steady and unsteady airfoil parameters using CFD was investigated to extend its applicability for VAWTs. This method permits the calculation of the blade dynamic stall characteristics over a range of reduced pitch rate by employing a user-defined sliding mesh motion. This technique was shown to be successful and can be employed where the required B-L model input empirical coefficients are not readily available and particularly useful for new airfoils. The variation in the blade Reynolds number over the VAWT operating envelope is also considered by this approach. The geometrical and operating specifications for a variable-speed 5 MW VAWT were identified. The VAWT solidity, blade orientation, blade aspect ratio and the support strut design was investigated. A VAWT solidity of 0.263 maximised the aerodynamic efficiency and ensured blade dynamic stall was avoided at the optimum TSR function regime. Results showed the concave-out configuration for the cambered blade increased the peak torque coefficient by 4.5% compared to the concave-in arrangement. It was observed that the blade aerodynamic forces were more sensitive to the blade orientation at low TSRs than at high TSRs. A non-prismatic tapered strut design was utilised and created a 6.5% reduction in the peak efficiency. Structural analysis of the blade structure subject to a critical load case was investigated with two methods, an analytical model and a finite element (FE) model. It was shown that the utilisation of a composite blade topology can resist the induced flapwise loading and the material strains were contained within their allowable limits. The analytical approach was demonstrated to be a quick and accurate technique to compute the composite blade strain distribution when compared to the FE model results. A 3D CFD model was employed to examine the 5MW VAWT aerodynamic phenomena and wake evolution. Dynamic stall causes the VAWT streamwise wake to become increasingly asymmetrical as the TSR is reduced. The impact of the blade tip vortex varies wit the azimuthal angle and the upwinde tip vortex is more intense compared to the downwide tip vortex. Blade end plates were investigated displaying a 4.71% increase and a 23.1% decrease in the mean torque coefficient for the upwind and downwind phases, respectively. A 0.73% reduction in peak efficiency was realised by utilising blade end plates. A tower fairing was also examined and was demonstrated to be an effective device to eliminate the vortex shedding created by the rotating VAWT tower