774 resultados para Paper addresses
Resumo:
In the context of burgeoning research on multinational corporations (MNCs), this paper addresses the issue of the representativeness of databases of MNCs in Ireland. It identifies some important deficiencies in existing databases much used by scholars in the field. Drawing on the international literature, it finds that this problem also characterises research on MNCs in many other countries. In the Irish context, we find that the extant empirical research has generally excluded two key categories of MNCs, namely, (a) foreign MNCs which are not grant-aided by the main industrial promotions agencies and (b) Irish-owned MNCs. The paper outlines our experience in identifying and addressing these deficiencies and describes the methods that might be employed in more precisely defining the MNC population in Ireland. More generally the paper reviews some of the issues and obstacles confronting scholars investigating the MNC sector in Ireland and abroad.
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This paper highlights the role of narratives in expressing, shaping and ordering urban life, and as tools for analysing urban conflicts. The paper distinguishes analytically between two prominent epistemological meta-narratives in contemporary urban studies and multiple ontological narratives in a given city-in this case Belfast. The first meta-narrative represents cities as sites of deepening coercion, violence and inequality and the second sees them as engines of new forms of transnational capitalism. Both are marked by the strategy of specifying 'exemplar' or 'paradigm' cities. The core of the paper addresses how these two meta-narratives map onto and interact with, three contemporary ontological narratives of urban regeneration in Belfast. We conceive of narratives-epistemological and ontological-as analytical tools and objects of analysis but also as tools for social action for competing political and economic interests and coalitions. While in the urban studies literature Belfast is typically studied as an exemplar 'conflict city', it is now being promoted as a 'new capitalist city'. In the context of post-Agreement Belfast, we explore not only the 'pull' of exemplar narratives but also resistances to them that are linked to multiple and hybrid senses of place in the city. We conclude that any significant move beyond the exigencies of rampant commodification or recurring inter-communal antagonism must firstly, encourage new forms of grassroots place-making and, secondly, reform of Belfast's (and Northern Ireland's) fragmented governance structures. © 2013 Copyright Taylor and Francis Group, LLC.
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Frequency stability has not necessarily been a major problem for the majority of power systems in the past. However, for economic and environmental reasons, power systems are now operated closer to stability limits to maximise the use of the existing networks. Therefore, introduction of new, more efficient and renewable generation technologies, and their effect on the power system must be fully understood if a reliable and secure electricity supply is to be maintained. Using the Northern Ireland, and interconnected Republic of Ireland electricity networks as a case study, this paper addresses some of the issues regarding integration and modelling of combined cycle gas turbines (CCGT), and wind turbine generator (WTG) technology on a small islanded power system.
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In finite difference time domain simulation of room acoustics, source functions are subject to various constraints. These depend on the way sources are injected into the grid and on the chosen parameters of the numerical scheme being used. This paper addresses the issue of selecting and designing sources for finite difference simulation, by first reviewing associated aims and constraints, and evaluating existing source models against these criteria. The process of exciting a model is generalized by introducing a system of three cascaded filters, respectively, characterizing the driving pulse, the source mechanics, and the injection of the resulting source function into the grid. It is shown that hard, soft, and transparent sources can be seen as special cases within this unified approach. Starting from the mechanics of a small pulsating sphere, a parametric source model is formulated by specifying suitable filters. This physically constrained source model is numerically consistent, does not scatter incoming waves, and is free from zero- and low-frequency artifacts. Simulation results are employed for comparison with existing source formulations in terms of meeting the spectral and temporal requirements on the outward propagating wave.
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Mortality models used for forecasting are predominantly based on the statistical properties of time series and do not generally incorporate an understanding of the forces driving secular trends. This paper addresses three research questions: Can the factors found in stochastic mortality-forecasting models be associated with real-world trends in health-related variables? Does inclusion of health-related factors in models improve forecasts? Do resulting models give better forecasts than existing stochastic mortality models? We consider whether the space spanned by the latent factor structure in mortality data can be adequately described by developments in gross domestic product, health expenditure and lifestyle-related risk factors using statistical techniques developed in macroeconomics and finance. These covariates are then shown to improve forecasts when incorporated into a Bayesian hierarchical model. Results are comparable or better than benchmark stochastic mortality models.
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The finite difference time domain (FDTD) method has direct applications in musical instrument modeling, simulation of environmental acoustics, room acoustics and sound reproduction paradigms, all of which benefit from auralization. However, rendering binaural impulse responses from simulated
data is not straightforward to accomplish as the calculated pressure at FDTD grid nodes does not contain any directional information. This paper addresses this issue by introducing a spherical array to capture sound pressure on a finite difference grid, and decomposing it into a plane-wave density
function. Binaural impulse responses are then constructed in the spherical harmonics domain by combining the decomposed grid data with free field head-related transfer functions. The effects of designing a spherical array in a Cartesian grid are studied, and emphasis is given to the relationships
between array sampling and the spatial and spectral design parameters of several finite-difference
schemes.
Resumo:
Following the UK Medical Research Council’s (MRC) guidelines for the development and evaluation of complex interventions, this study aimed to design, develop and optimise an educational intervention about young men and unintended teenage pregnancy based around an interactive film. The process involved identification of the relevant evidence base, development of a theoretical understanding of the phenomenon of unintended teenage pregnancy in relation to young men, and exploratory mixed methods research. The result was an evidence-based, theory-informed, user-endorsed intervention designed to meet the much neglected pregnancy education needs of teenage men and intended to increase both boys’ and girls’ intentions to avoid an unplanned pregnancy during adolescence. In prioritising the development phase, this paper addresses a gap in the literature on the processes of research-informed intervention design. It illustrates the application of the MRC guidelines in practice while offering a critique and additional guidance to programme developers on the MRC prescribed processes of developing interventions. Key lessons learned were: 1) know and engage the target population and engage gatekeepers in addressing contextual complexities; 2) know the targeted behaviours and model a process of change; and 3) look beyond development to evaluation and implementation.
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The paper addresses two connected questions: firstly, in what ways might ‘public’ and ‘private’ spaces in cities be gendered; and secondly, what might this mean for the possibilities for complex forms of civility in a divided city such as Belfast? The specific focus on gendered dynamics of entitlement to inhabit urban space in this paper begins with some consideration of debates about the quality and experience of everyday life in cities, and the emergence of commonsense notions of ‘public’ and ‘private’ behaviour. Following this, key research concerned with the gendered dynamics of claimed collective, and particularly national, identities are outlined, in order to consider the significance of this literature for any study of the gender dynamics of life in a contested political context such as Belfast.
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The paper addresses the issue of choice of bandwidth in the application of semiparametric estimation of the long memory parameter in a univariate time series process. The focus is on the properties of forecasts from the long memory model. A variety of cross-validation methods based on out of sample forecasting properties are proposed. These procedures are used for the choice of bandwidth and subsequent model selection. Simulation evidence is presented that demonstrates the advantage of the proposed new methodology.
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System efficiency and cost effectiveness are of critical importance for photovoltaic (PV) systems. This paper addresses the two issues by developing a novel three-port DC-DC converter for stand-alone PV systems, based on an improved Flyback-Forward topology. It provides a compact single-unit solution with a combined feature of optimized maximum power point tracking (MPPT), high step-up ratio, galvanic isolation and multiple operating modes for domestic and aerospace applications. A theoretical analysis is conducted to analyze the operating modes followed by simulation and experimental work. The paper is focused on a comprehensive modulation strategy utilizing both PWM and phase-shifted control that satisfies the requirement of PV power systems to achieve MPPT and output voltage regulation. A 250 W converter was designed and prototyped to provide experimental verification in term of system integration and high conversion efficiency.
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The paper addresses the possibility of the existence of a ‘hidden curriculum’ in nineteenth- and early twentieth-century National Schools by comparing working practices evident from an analysis of a sample of schools from two case study areas in the north of Ireland – Derry City and the rural area of Boho/Derrygonnelly in western County Fermanagh. The relationship between the placement of the school buildings and variations in their external appearances are examined in respect to their relationships with different churches. The possible significance of this relationship is scrutinised given that the primary aim of the National School system was joint secular education in a religiously divided society. Both the external and internal architecture of the buildings are also examined for the purposes of reconstructing aspects of the intentions and practices that governed their use. In particular, the relationship between allocated space and the categories of age and gender are studied by means of an access analysis of the floor plans of a representative sample of primary schools from both case study areas. Information derived from oral history accounts, archived material from the Public Record Office of Northern Ireland (PRONI) and school registers is used to supplement the findings obtained from the architectural analyses.
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The potential use of Irish-grown Sitka spruce for cross-laminated timber (CLT) manufacture is investigated as this would present new opportunities and novel products for Irish timber in the home and export markets. CLT is a prefabricated multilayer engineered wood product made of at least three orthogonally bonded layers of timber. In order to increase rigidity and stability, successive layers of boards are placed cross-wise to form a solid timber panel. Load-bearing CLT wall and floor panels are easily assembled on site to form multi-storey buildings. This improves construction and project delivery time, reduces costs,
and maximises efficiency on all levels.
The paper addresses the quality of the interface bond between the laminations making up the panels, which is of fundamental importance to the load bearing capacity. Therefore, shear tests were carried out on nine test bars of three glue lines each. Moreover, delamination tests were performed on samples subjected to accelerated aging, in order to assess the durability of bonds subjected to severe environmental conditions. In addition, this paper gives an indication on thickness tolerances of planed Irish Sitka spruce lamellas, which is likely to be a critical factor for bonding quality and adhesive selection. The test results of bond quality presented in this study were within requirements of prEN 16351:2013.
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This paper addresses the problems of effective in situ measurement of the real-time strain for bridge weigh in motion in reinforced concrete bridge structures through the use of optical fiber sensor systems. By undertaking a series of tests, coupled with dynamic loading, the performance of fiber Bragg grating-based sensor systems with various amplification techniques were investigated. In recent years, structural health monitoring (SHM) systems have been developed to monitor bridge deterioration, to assess load levels and hence extend bridge life and safety. Conventional SHM systems, based on measuring strain, can be used to improve knowledge of the bridge's capacity to resist loads but generally give no information on the causes of any increase in stresses. Therefore, it is necessary to find accurate sensors capable of capturing peak strains under dynamic load and suitable methods for attaching these strain sensors to existing and new bridge structures. Additionally, it is important to ensure accurate strain transfer between concrete and steel, adhesives layer, and strain sensor. The results show the benefits in the use of optical fiber networks under these circumstances and their ability to deliver data when conventional sensors cannot capture accurate strains and/or peak strains.
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Photovoltaic (PV) solar power generation is proven to be effective and sustainable but is currently hampered by relatively high costs and low conversion efficiency. This paper addresses both issues by presenting a low-cost and efficient temperature distribution analysis for identifying PV module mismatch faults by thermography. Mismatch faults reduce the power output and cause potential damage to PV cells. This paper first defines three fault categories in terms of fault levels, which lead to different terminal characteristics of the PV modules. The investigation of three faults is also conducted analytically and experimentally, and maintenance suggestions are also provided for different fault types. The proposed methodology is developed to combine the electrical and thermal characteristics of PV cells subjected to different fault mechanisms through simulation and experimental tests. Furthermore, the fault diagnosis method can be incorporated into the maximum power point tracking schemes to shift the operating point of the PV string. The developed technology has improved over the existing ones in locating the faulty cell by a thermal camera, providing a remedial measure, and maximizing the power output under faulty conditions.
Resumo:
The parasitical relationship between the grand piano and the myriad objects used in its preparation as pioneered by John Cage in the late 1940’s is here discussed from a perspective of free improvisation practice. Preparations can be defined as the use of a “non-instrument” object (screws, bolts, rubbers etc…) to alter or modify the behaviour of an instrument or part of an instrument. Although also present in instrumental practices based on the electric guitar or the drum kit, the piano provides a privileged space of exploration given its large‐scale resonant body. It also highlights the transgressive aspect of preparation (the piano to be prepared often belongs to a venue rather than to the pianist herself, hence highlighting relationships of trust, care and respect). Since 2007 I have used a guitar-object (a small wooden board with strings and pick ups) connected to a small amplifier to prepare the grand piano in my free improvisation practice. This paper addresses the different relationships afforded by this type preparation which is characterised by the fact that the object for preparation is in itself an instrument (albeit a simplified one), and the preparation is ephemeral and intrinsic to the performance. The paper also reflects on the process of designing an interface from and for a particular practice and in collaboration with a guitar luthier.