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This paper examines the Random Walk Hypothesis (RWH) for aggregate New Zealand share market returns, as well as the CRSP NYSE‐AMEX (USA) index during the 1980‐2001 period. Using several indices, we rely on the variance‐ratio test and find evidence to support the rejection of the RWH with some evidence of a momentum effect. However, we find evidence to suggest the behaviour of share prices to be time‐dependent in New Zealand. For example, we find the indices tested were closer to random after the 1987 share market crash. Further analysis showed even stronger results for periods subsequent to the passage of the Companies Act 1993 and the Financial Reporting Act 1993. We also find evidence that indices based on large capitalisation stocks are more likely to follow a random walk compared to those based on smaller stocks. For the USA index, we find stronger evidence of random behaviour in our sample period compared to the earlier period examined by Lo and Mackinlay (1988)

The bulk of jet engine noise developed at high powers arises from the turbulent mixing of the jet efflux in the surrounding air, as judged from model experiments, and has a continuous spectrum with a single flat maximum. The high frequency sound arises from fairly close to the orifice, and reaches its maximum intensity at fairly large acute angles to the jet direction. Lower frequency noise arises from lower down stream and its maxima make smaller acute angles with the jet axis. The possible origins are briefly discussed in view of Lighthill's theory and refraction effects. The most intensesound has a wave‐length of the order of three or four exit diameters, and originates between five and ten diameters from the orifice. A semi‐empirical rule of noise energy depending on the jet velocity to the eighth power and the jet diameter squared gives a rough estimate of the noise level for both cold and heated jets. Further noise from heated or supersonic jets may occur through eddies travelling at supersonic speed and so producing small Shockwaves. Model experiments have shown that interaction between shock‐wave configurations in choked jets and passing eddy trains generates sound and this initiates further eddies at the orifice. The directional properties of this sound are quite distinctive, the maximum being in the upstream direction. Methods of reducing jet noise are briefly discussed.

Analysing the intersectional race and gender politics of the England women's national team, this chapter, based on oral history interviews, shows the historical forces shaping the diversity of the squad over time, from 1972 to the present. Class is important here, as many of the first black and mixed heritage England women players were the daughters of the Windrush generation of Caribbean migrants who settled in working-class areas of urban, and to a lesser extent, rural England. In the case of London-based players, this gave a proximity to important development centres, available by public transport. In the case of Kerry Davis, from Stoke on Trent, access to private transport was important. As head coach, Hope Powell oversaw the first Black-British captain of an England women's side, but when succeeded by Mark Sampson much of this development receded, notably as Eni Aluko, a centurion capped star of Nigerian descent was de-selected for ‘Unlioness behaviour’. In the ensuing legal analysis, the FA showed itself to lack awareness of diversity and inclusion issues in its own sport. The chapter analyses the effect of this, on an England team that includes several high profile LGBTQ+ stars, which is diverse in different ways than the England men's team.

Increased demands from North Sea oil has provided the opportunity for a Kent manufacturer of electrical terminal boxes to build a new factory.

THE nuisance caused by the noise produced by aircraft is a matter which has been arousing antagonism now for some forty years and there have been repeated demands that ‘something should be done about it’.

THE St. Venant theory as applied to long beams of constant cross‐section could generally be used with sufficient accuracy for the solution of the structures encountered in aircraft until the last few years. The wings of high‐speed aircraft, with smaller aspect ratios, large angles of sweep‐back, and small thickness/chord ratios, introduce a new problem. There is an extensive literature on the subject, and all the methods which have been proposed are necessarily studies of redundant systems, the degree of redundancy varying according to the accuracy required. As these solutions require that the scantlings of the structure be known in advance, it was thought interesting to establish a simple method which would determine to a good approximation the skin thicknesses required. This is based on the application of the theorem of least work, which gives exact solutions of elasticity problems so long as all the terms in the strain energy expression are taken into account.

A Theoretical Approach to Assessing the Thermodynamic Process Within the Combustion Chamber of the Propulsive Duct, an Examination of the Potential of the Duct with Special Reference to the Application of Feedback and Spark Discharge Techniques. Development of the propulsive duct has been retarded by the absence of a suitable theoretical analysis. This paper, based on four years of experimental investigation by the author, discusses the problems involved and puts forward a theory which closely follows practical results. The theory is then used to examine the potential of the duct and it is shown that by applying feedback and spark‐discharge techniques, a low specific fuel consumption and unlimited thrust, outside the audible range, is theoretically possible. Finally, it is shown that the marriage of the duct to electrical power generated from atomic sources otters attractive possibilities for V.T.O.L. and aircraft propulsion of the future.

Output from the Irish Dairy Industry has grown rapidly since the abolition of quotas in 2015, with processors investing heavily in capacity expansion to deal with the extra milk volumes. Further capacity gains may be achieved by extending the processing season into the winter, a key enabler for which being the reduction of duration of the winter maintenance overhaul period. This paper aims to investigate if Lean Six Sigma tools and techniques can be used to enhance operational maintenance performance, thereby releasing additional processing capacity.

Combining the Six-Sigma Define, Measure, Analyse, Improve, Control (DMAIC) methodology and the structured approach of Turnaround Maintenance (TAM) widely used in process industries creates a novel hybrid model that promises substantial improvement in maintenance overhaul execution. This paper presents a case study applying the DMAIC/TAM model to Ireland’s largest dairy processing site to optimise the annual maintenance shutdown. The objective was to deliver a 30% reduction in the duration of the overhaul, enabling an extension of the processing season.

Application of the DMAIC/TAM hybrid resulted in process enhancements, employee engagement and a clear roadmap for the operations team. Project goals were delivered, and original objectives exceeded, resulting in €8.9m additional value to the business and a reduction of 36% in the duration of the overhaul.

The results demonstrate that the model provides a structure that promotes systematic working and a continuous improvement focus that can have substantial benefits for wider industry. Opportunities for further model refinement were identified and will enhance performance in subsequent overhauls.

To the best of the authors’ knowledge, this is the first time that the structure and tools of DMAIC and TAM have been combined into a hybrid methodology and applied in an Irish industrial setting.

The purpose of this paper is to report on an evaluation of the UK Healthy Universities Network (UKHUN), which explored engagement of network members; identified what members value about the network; examined facilitators and barriers to engagement; and informed the network’s future development.

The study was a two phase mixed-method study, with participants being staff from Higher Education institutions. Phase 1 involved a documentary review and an online 14-question survey (n=32). Phase 2 comprised follow-up semi-structured interviews and focus groups, conducted using Skype (n=11). These were audio recorded and transcripts were thematically analysed in a two-stage process.

A number of key themes emerged from the thematic analysis: value of network meetings and events; popularity of the network website; increased communication and collaboration; sense of leadership offered by the network; interest and inclusion of an international perspective; importance of institutional support.

Only six universities who are involved in the network took part in Phase 2. Although a range of organisations were chosen purposively, it is possible that additional key issues at other universities were excluded.

The UKHUN is valued by its membership, particularly its biannual meetings, online presence, leadership, ethos and communication methods. Key barriers include the capacity of staff to attend meetings and contribute to the network, influenced by a lack of institutional commitment and prioritisation. Findings from the evaluation have informed a “refresh” of the network’s website and a revision of its membership structure, as well as guiding its positioning to achieve greater strategic influence.