Measurement technique to assess the acoustic properties of a silencer component for transient engine conditions

This paper describes the development and validation of procedures for measuring the acoustic properties of an individual component of an exhaust system on a test bed under engine acceleration representing realistic operating conditions. However, collection of such data requires reliable induct pressure measurements where the contamination of the acoustic pressure field by shear layer turbulence and other hydrodynamic disturbances [1] make this a formidable challenge. The technique was first developed and optimized on a cold flow bench to simulate partly the acoustic conditions during engine acceleration, before applying it to an actual vehicle. Bench test results showed that order analysis measurement techniques can be employed to evaluate the acoustic performance of a silencer component for variable harmonic excitation in the presence of mean flow. The additional factors concerned in performing measurements on the test bed are illustrated by some preliminary measurements

Board diversity in the United Kingdom and Norway : an exploratory analysis

This paper examines the evolving pattern of gender diversity of the boards of directors of leading Norwegian and British companies on a longitudinal basis. The period covered by the study covers the run up to proposed affirmative action legislation in Norway and, as such, affords an insight into corporate actions in this emerging institutional context. The findings demonstrate that, while board diversity has grown substantially in both countries in recent years, it has done so considerably more rapidly in Norway than in the United Kingdom. The analysis highlights the sectoral variation between the countries in the pattern and growth of board diversity and suggests that the vast majority of the overall growth in board diversity is the result of changing firm behaviour rather than sectoral shift in the United Kingdom or Norwegian economies. It is also shown that as diversity has increased there has been no fall in how experienced female directors are; neither is there evidence of a rise in the number of boards that female directors sit on. This suggests that the rapid growth in board diversity has been achieved without any fall in the quality of female directors.14 page(s