National University of Ireland, Maynooth
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Climate change impacts on spatial and seasonal meteorological drought characteristics for the island of Ireland
No full textUnderstanding how climate change is likely to impact on meteorological droughts is key to informing adaptation planning. For Ireland, little research has examined how droughts are likely to change in future. Here we examine changes in the monthly climate water balance, aridity index and changes in magnitude, frequency and duration of droughts using standardized drought indices for the island of Ireland derived from bias-adjusted CORDEX simulations for the 2080s(2070–2099), forced with a high (RCP8.5) and moderate (RCP4.5) emissions path-way. Findings highlight that increases in potential evapotranspiration, driven by increasing temperature, together with changing seasonal rainfall patterns increase aridity in summer with water deficits extending into spring months, especially in the east and midlands by the end of the century. Increases in drought frequency and magnitude are also evident, with greatest increases for RCP8.5. Critically, increases are considerably greater for the standardized precipitation evapotranspiration index (SPEI) than for the standardized precipitation index (SPI), emphasizing the importance of using metrics that capture potential evapotranspiration in monitoring and assessing future drought risk. Summer and spring show the greatest increase in drought magnitude and frequency, most marked in the east of the island. By contrast, multi seasonal droughts, assessed using 6-month accumulation periods show more modest changes in magnitude and duration. The resultant impacts of climate change on drought for Ireland would require considerable adaptation given the vulnerabilities exposed by the 2018 drough
Laser-Powered UAVs for Wireless Communication Coverage: A Large-Scale Deployment Strategy
No full textThe use of unmanned aerial vehicles (UAVs) is strongly advocated for sixth-generation (6G) networks, as the 6G standard will not be limited to improving broadband services, but will also target the extension of the geographical cellular coverage. In this context, the deployment of UAVs is considered a key solution for seamless connectivity and reliable coverage. That being said, it is important to underline that although UAVs are characterized by their high mobility and their ability to establish line-of-sight (LOS) links, their use is still impeded by several factors such as weather conditions, their limited computing power, and, most importantly, their limited energy. In this work, we are aiming for the novel technology that enables indefinite wireless power transfer for UAVs using laser beams. We propose a novel UAV deployment strategy, based on which we analyze the overall performance of the system in terms of wireless coverage. To this end, we use tractable tools from stochastic geometry to model the complex communication system. We analyze the user’s connectivity profile under different laser charging capabilities and in different type of environments. We show a decrease in the coverage probability by more than 12% in moderate-to-strong turbulence conditions compared to low turbulence conditions. We also show how the connection rate to the aerial network significantly decreases in favor of the terrestrial network for short laser charging ranges. We conclude that laser-powered drones are considered interesting alternatives when placed in LOS with users, in low-to-moderate optical turbulence, and at reasonable ranges from the charging stations
Nonparametric multivariate survival analysis of activated lymphocyte cell fates.
No full textUpon challenge, lymphocytes multiply and diversify to combat the infection,
however, the mechanisms that drive this process are not well understood. A
theoretical model has been proposed to explain how a diverse selection of
cell fates is achieved, the Cyton model [Hawkins et al, 2007, PNAS]. In that
model the censorship caused by competing drives for lymphocytes to undergo
certain fates results in complex correlations and impacts the observed
distribution of times to cellular events. In [Duffy et al, 2012, Science] the
competition hypothesis is tested for consistency with data collected using
a novel experimental procedure. Through the implementation and development
of a collection of multivariate nonparametric statistical techniques, we
create a set of tools that can aid the study of competition hypotheses in
biological systems. As a worked example these tools are used to study data
collected for the experiments in [Duffy et al, 2012, Science] to challenge some
of the underlying assumptions of their parametric analysis. As an additional
illustration further unpublished data collected during the experiments is used
to study the time at which B cells divide, die and differentiate when they
have already undergone class switching, allowing us to address the question
of a cell type dependent change
Tying the Knot – Linking Bootstrapping and Working Capital Management in Established Enterprises
No full textPurpose – Bootstrapping is a practitioner-based term adopted in entrepreneurship to describe the techniques
employed in micro, small and medium-sized enterprises (MSMEs) to minimise the need for external funding by
securing resources at little or no cost and applying strategies to effectively use resources. Working capital
management (WCM) is a term used in financial management to define a set of practices used to manage
business resources, including cash management. This paper explores the overlap and divergence between
these two disciplinary distinct concepts.
Design/methodology/approach – A dual methodology is employed. First, the usage of the two terms in
prior literature is analysed and synthesised. Second, the study uses factor analysis to explore how
bootstrapping practices described by owners of 167 established MSMEs relate to the components of WCM in
financial management.
Findings – The factor analysis identifies two main bootstrapping practices employed by MSMEs: (1) delaying
payments and owner-related bootstrapping and (2) customer-related bootstrapping. Delaying payments is an
integral practice in trade payables management and customer-related bootstrapping includes practices that are
integral to trade receivables management. Therefore, links between bootstrapping practices and WCM
practices are firmly established.
Research limitations/implications – The study is not without limitations. Based on cross-sectional
evidence for established firms in Ireland only, future studies could explore cross-country longitudinal panel
data to fully examine life cycle and sectoral effects, as well as other external shocks (for example, COVID-19) on
bootstrapping and WCM practices. This study does not explain why some factors (for example, joint utilisation
and inventory management) are present in some bootstrapping studies and not in others; further case study
research might help explain this. Finally, changes in the business environment facing start-ups and established
enterprise, including increased digitalisation, online trading, self-employment, remote hub working and
sustainability, offer new avenues for bootstrapping research.
Originality/value – This is the first study to comprehensively explore the conceptual and empirical links
between bootstrapping and WCM. This study will enable researchers and practitioners in these two distinct
disciplines to learn from each other. Accounting researchers and practitioners can broaden their understanding
of how WCM “works”in MSME settings. Similarly, entrepreneurship researchers and practitioners can deepen
their understanding of how bootstrapping can be adopted by businesses to manage resources effectively
‘Strikingly and stubbornly high’: Investigating the paradox of public confidence in the Irish police
No full textWhile levels of public confidence in the police have declined internationally, the Republic of Ireland appears to have bucked this trend with confidence levels that remain ‘strikingly and stubbornly high’ ( Mulcahy, 2016: 275). This situation appears all the more puzzling given the wave of scandals to have hit the force in recent decades, ranging from police corruption in Donegal in the late 1990s to a more recent whistleblower scandal that has resulted in the resignation of a slew of Ministers and high-ranking officials. Such developments beg important questions as to the factors sustaining public confidence over this tumultuous period. Drawing on international and domestic data, this article aims to probe this ‘paradox’ of public confidence in the Irish police. It argues that, although confidence is high, there is more to the dynamics of confidence in the police in Ireland than this initial appraisal suggests. Indeed, it advances the Irish case as an illustration both of the dimensionality of the public confidence concept and the complexity of the pathways to trust in the police
Optimising industry learners’ online experiences – lessons for a post-pandemic world
No full textThis study examines the experiences and impact COVID-19 has had on industry online learners. Exploring initially the term ‘industry learner' and explaining the background to the design of the online modules the learners participated on. The design and delivery of this programme resulted in minimal impacts from the COVID-19 pandemic. The study explores qualitative reports of industry learners’ experiences, and these are analysed using thematic analysis. The findings suggest that the design principle of maximising social interaction, at peer to peer and peer to educator levels, resulted in an enhanced student experience. Group based interactions were recognised by learners as both an occasional source of friction, but also as a valuable proxy for industry leadership roles and workplace group dynamics. This highlights the complex enhancing and inhibiting nature of group-based learning. Implications for further optimisation of online and blended learning environments are explored and associated future research priorities are identified
Refining a forecasting method for first emergence of an important forestry pest (Hylobius abietis) in Ireland through environmental modelling
No full textLarge pine weevil (Hylobius abietis) is a serious pest of coniferous plantations throughout Northern Europe including in Ireland, causing significant mortality in replanted trees. Replanted trees are new transplants set on clear fell sites. This mortality results in severe economic losses to foresters (Langstrom and Day, 2004). Development of weevils takes place in the stumps of felled conifer trees and emerging adults feed directly on new transplants on site. Currently, young trees are mainly protected by chemical insecticides applied when weevil attack is anticipated. In Integrated Pest Management (IPM), adequate timing of management actions can help reduce the necessity for pesticides, or the amount used. In the case of pine weevil, forecasting the extent of weevil infestation is centred around the process of stump hacking to estimate numbers of weevils developing there (Teagasc, 2020). The research outlined here adapts an existing UK simulation model developed to determine geographic variation in voltinism of pine weevil under climate change (Wainhouse et al., 2014) to forecast timing of first year emergence of pine weevil in Ireland. The model utilises historical temperature data, derived either from nearest synoptic stations (weighted for distance) or interpolated gridded (Walsh, 2012) to forecast cumulative weevil emergence for specific sites and years for which existing biological data of emerging weevil populations were available. Observed and model simulated emergence patterns were compared, both for an early version of the model and a corrected version (adapted with the machine learning algorithm random forest). Site-specific co-variates that affect the model forecast simulations of weevil emergence were identified. Previous research at Maynooth University (Williams et al., unpublished) had demonstrated that the original implementation of the UK model could be used to predict site-specific patterns of weevil emergence based on data from local weather stations. This project builds on these findings, resulting in the development of the pineR model, incorporating data from additional sites to detect potential site-specific factors of influence, such as elevation, that could be considered to provide more accurate predictions of first year weevil emergence in Ireland. It also lays the groundwork for future work that would potentially incorporate information on weevil population structure in stumps to create an accessible version of the model using the in-stump values and local weather data to forecast timing of weevil emergence from a specific stage. It is envisaged that pineR will ultimately help refine the stump assessment protocol (i.e., stump hacking) currently used by foresters in Ireland
Equilibrium existence and expected payoffs in all-pay auctions with constraints
No full textThis paper introduces constraints on player choices in a broad class of all-pay auctions
by allowing for upper bounds on players’ strategy sets. It proves the existence of
equilibrium and derives simple closed-form formulae for players’ expected payoffs in
any equilibrium. These formulae are straightforward to calculate in applications and do
not require the derivation of the equilibrium or equilibria. This may be useful because:
(i) In some applications players’ expected payoffs are the main item of interest. For
example, one may be concerned about the effect of a policy on the market participants.
In these cases the results can be used directly, bypassing the need for the full derivation
of the equilibrium. (ii) In all-pay auctions, equilibrium is typically in mixed strategies.
So in applications where the full characterization of the equilibrium is of interest,
finding the players’ expected payoffs is a crucial first step in the derivation of the
equilibrium
‘Cocooning’ in prison during COVID-19: Findings from recent research in Ireland
No full textThe advent of COVID-19 prompted the enforced isolation of elderly and vulnerable populations
around the world, for their own safety. For people in prison, these restrictions risked compounding the isolation and harm they experienced. At the same time, the pandemic created barriers to
prison oversight when it was most needed to ensure that the state upheld the rights and wellbeing
of those in custody. This article reports findings from a unique collaboration in Ireland between
the Office of the Inspector of Prisons – a national prison oversight body – and academic criminologists. Early in the pandemic, they cooperated to hear the voices of people ‘cocooning’ –
isolated because of their advanced age or a medical vulnerability – in Irish prisons by providing
journals to this cohort, analysing the data, and encouraging the Irish Prison Service to change practices accordingly. The findings indicated that ‘cocooners’ were initially ambivalent about these new
restrictions, both experiencing them as a punishment akin to solitary confinement, and understanding the goal of protection. As time passed, however, participants reported a drastic impact
on their mental and physical health, and implications for their (already limited) agency and relationships with others, experienced more or less severely depending on staff and management practices. The paper also discusses the implications for prison practices during and following the
pandemic, understanding isolation in the penological context, and collaboration between prison
oversight bodies and academics