Dublin City University

About: Dublin City University is a education organization based out in Dublin, Ireland. It is known for research contribution in the topics: Context (language use) & Machine translation. The organization has 5904 authors who have published 17178 publications receiving 389376 citations. The organization is also known as: National Institute for Higher Education, Dublin & DCU.

Temperature-corrected pressure-sensitive paint measurements using a single camera and a dual-lifetime approach

Abstract: The temperature dependence of luminescent coatings which measure surface pressure is a well established problem. Temperature correction of the surface pressure measurement is often carried out by incorporating a second luminescent coating or by co-immobilizing a second luminophore to provide a surface temperature profile. This usually complicates the measurement process by requiring a second camera or sophisticated filtering to distinguish between the two luminescent processes. Here, a single-camera, temperature-corrected PSP (pressure-sensitive paint) system was developed. A new oxygen-permeable sol–gel-based paint, containing both a temperature- and a pressure-sensitive luminophore is described. The fluorescence decay times of the two luminophores are separated by several orders of magnitude. This allows pressure- and temperature-dependent luminescent decay measurements to be separated in the time domain. In addition, the two luminophores were selected such that their absorption and emission spectra occur in similar spectral regions. This avoids the need for different excitation sources or detection filters. Hence a single camera with a gated image intensifier can be used to measure the lifetime of each luminophore within the same cycle. Image alignment issues experienced in dual-camera systems are also avoided. This new PSP has the potential to provide a temperature-corrected surface pressure profile using a single excitation source and detection system.

Quasi-static response and multi-objective crashworthiness optimization of oblong tube under lateral loading

Abstract: This paper addresses the energy absorption responses and crashworthiness optimization of thin-walled oblong tubes under quasi-static lateral loading. The oblong tubes were experimentally compressed using three various forms of indenters named as the flat plate, cylindrical and a point load indenter. The oblong tubes were subjected to inclined and vertical constraints to increase the energy absorption capacity of these structures. The variation in responses due to these indenters and external constraints were demonstrated. Various indicators which describe the effectiveness of energy absorbing systems were used as a marker to compare the various systems. It was found that unconstrained oblong tube (FIU) exhibited an almost ideal response when a flat plate indenter was used. The design information for such oblong tubes as energy absorbers can be generated through performing parametric study. To this end, the response surface methodology (RSM) for the design of experiments (DOE) was employed along with finite element modeling (FEM) to explore the effects of geometrical parameters on the responses of oblong tubes and to construct models for the specific energy absorption capacity (SEA) and collapse load ( F ) as functions of geometrical parameters. The FE model of the oblong tube was constructed and experimentally calibrated. In addition, based on the developed models of the SEA and F , multi-objective optimization design (MOD) of the oblong tube system is carried out by adopting a desirability approach to achieve maximum SEA capacity and minimum F . It is found that the optimal design of FIU can be achieved if the tube diameter and tube width are set at their minimum limits and the maximum tube thickness is chosen.

Parliamentary Questions, the Behaviour of Legislators, and the Function of Legislatures: An Introduction

Abstract: The ability of parliamentarians to ask questions of members of the executive either in written form or on the floor of the chamber is a feature of many legislatures. Parliamentary questions often generate significant media attention and public interest. Despite the interest and importance, the nature and consequences of questioning in parliament remains obscure. As a working tool of parliamentarians, questions provide recorded data on individual members and the parliament as a collective institution. This paper suggests an analysis of parliamentary questions as a method for gaining better understanding of the preferences and behaviour of individual legislators and the role and function of modern-day parliaments.