Why do people opt-out or not opt-out of automatic enrolment? A focus group study of automatic enrolment into a workplace pension in the United Kingdom

Automatic enrolment (AE) into a workplace pension is an important recent development in pension policy. An important question for this policy is why do people opt-out or not opt-out of AE? This question is important for understanding the power of suggestion associated with AE as well as responding to concerns that women might face undue pressure to opt-out. This article addresses this question through a focus group study into the United Kingdom’s new AE policy. Women were more likely than men to cite lack of affordability as a reason for opting out. Lack of information also seemed important for the power of suggestion associated with AE. Further research should explore how to make AE less gender blind as well as the types of information or advice that should be provided alongside AE

Modal analysis of high frequency acoustic signal approach for progressive failure monitoring in thin composite plates

During the past few decades, many successful research works have evidently shown remarkable capability of Acoustic Emission (AE) for early damage detection of composite materials. Modal Analysis of AE signals or Modal Acoustic Emission (MAE) offers a better theoretical background for acoustic emission analysis which is necessary to get more qualitative and quantitative result. In this paper, the application of MAE concept in a single channel AE source location detection method for failure characterization and monitoring in thin composite plates was presented. Single channel AE source location is one of the recent studies for composite early damage localization, owing to the growing interest and knowledge of modal analysis of AE wave. A tensile test was conducted for glass fiber epoxy resin specimen with small notch. A single channel of AE system was used to determine the AE source location on specimen under testing. The results revealed that AE single channel source location provides reasonable accuracy for glass fiber laminate which was tested

Review: Acoustic emission technique - Opportunities, challenges and current work at QUT

Acoustic emission (AE) is the phenomenon where high frequency stress waves are generated by rapid release of energy within a material by sources such as crack initiation or growth. AE technique involves recording these stress waves by means of sensors placed on the surface and subsequent analysis of the recorded signals to gather information such as the nature and location of the source. AE is one of the several non-destructive testing (NDT) techniques currently used for structural health monitoring (SHM) of civil, mechanical and aerospace structures. Some of its advantages include ability to provide continuous in-situ monitoring and high sensitivity to crack activity. Despite these advantages, several challenges still exist in successful application of AE monitoring. Accurate localization of AE sources, discrimination between genuine AE sources and spurious noise sources and damage quantification for severity assessment are some of the important issues in AE testing and will be discussed in this paper. Various data analysis and processing approaches will be applied to manage those issues

Characterization of Acoustic Emissions from Mechanical Seals for Fault Detection

The application of high-frequency Acoustic Emissions (AE) for mechanical seals diagnosis is gaining acceptance as a useful complimentary tool. This paper investigates the AE characteristics of mechanical seals under different rotational speed and fluid pressure (load) for develop a more comprehensive monitoring method. A theoretical relationship between friction in asperity contact and energy of AE signals is developed in present work. This model demonstrates a clear correlation between AE Root Mean Square (RMS) value and sliding speed, contact load and number of contact asperities. To benchmark the proposed model, a mechanical seal test rig was employed for collecting AE signals under different operating conditions. Then, the collected data was processed using time domain and frequency domain analysis methods to suppressing noise interferences from mechanical system for extracting reliably the AE signals from mechanical seals. The results reveal the potential of AE technology and data analysis method applied in this work for monitoring the contact condition of mechanical seals, which will be vital for developing a comprehensive monitoring systems and supporting the optimal design and operation of mechanical seals

Characterising the friction and wear between the piston ring and cylinder liner based on acoustic emission analysis

In this paper, an experimental investigation was carried out to evaluate the friction and wear between the cylinder liner and piston ring using acoustic emission (AE) technology. Based on a typical compression ignition (CI) diesel engine, four types of alternative fuels (Fischer-Tropsch fuel, methanol-diesel, emulsified diesel and standard diesel) were tested under dif-ferent operating conditions. AE signals collected from the cylinder block of the testing en-gine. In the meantime, the AE signals in one engine cycle are further segregated into small segments to eliminate the effects of valve events on friction events of cylinder liner. In this way, the resulted AE signals are consistent with the prediction of hydrodynamic lubrication processes. Test results show that there are clear evidences of high AE deviations between dif-ferent fuels. In particular, the methanol-diesel blended fuel produces higher AE energy, which indicates there are more wear between the piston ring and cylinder liner than using standard diesel. On the other hand, the other two alternative fuels have been found little dif-ferences in AE signal from the normal diesel. This paper has shown that AE analysis is an ef-fective technique for on-line assessment of engine friction and wear, which provides a novel approach to support the development of new engine fuels and new lubricants

Characterisation of Al corrosion and its impact on the mechanical performance of composite cement wasteforms by the acoustic emission technique

In this study acoustic emission (AE) non-destructive method was used to evaluate the mechanical performance of cementitious wasteforms with encapsulated Al waste. AE waves generated as a result of Al corrosion in small-size blast furnace slag/ordinary Portland cement wasteforms were recorded and analysed. The basic principles of the conventional parameter-based AE approach and signal-based analysis were combined to establish a relationship between recorded AE signals and different interactions between the Al and the encapsulating cement matrix. The AE technique was shown as a potential and valuable tool for a new area of application related to monitoring and inspection of the mechanical stability of cementitious wasteforms with encapsulated metallic wastes such as Al