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Machine builders often use mechanical solutions to translate a rotation motion into linear motion, and to synchronize several axes with one another, or with other moving parts. Higher production speeds are usually obtained by faster machine cycles, but mechanical limitations are increasingly leading machine builders to use electronic camming and gearing.

The purpose of this paper is to minimize the volume of straight bevel gear and to develop resistance towards scoring failure in the straight bevel gear. Two evolutionary and more advance optimization techniques were used for performing optimization of straight bevel gears, which will also save computational time and will be less computationally expensive compared to a previously used optimization for design optimization of straight bevel gear.

The following two different cases are considered for the study: the first mathematical model similar to that used earlier and without any modification to show efficiency of the optimization algorithm for straight bevel gear design optimization and the second mathematical model consist of constraints on scoring and contact ratio along with other generally used design constraints. Real coded genetic algorithm (RCGA) and accelerated particle swarm optimization (APSO) are used to optimize the straight bevel gear design. The effectiveness of the algorithms used has been validated by comparing the obtained results with previously published results.

It has been found that APSO and RCGA outperform other algorithms for straight bevel gear design. Optimized design values have reduced the scoring effect significantly. The values of the contact ratio obtained further enhances the meshing operation of the bevel gear drive by making it smoother and quieter.

Low volume is one of the essential requirements of gearing applications. Scoring is a critical gear failure aspect that leads to the broken tooth in both high speed and low-speed applications of gears. The occurrence of scoring is hard to detect early and analyse. Scoring failure and contact ratio have been introduced as design constraints in the mathematical model. So, the mathematical model demonstrated in this paper minimizes the volume of the straight bevel gear drive, which has been very less attempted in previous studies, with scoring and contact ratio as some of the important design constraints, which the objective function has been subjected to. Also, two advanced and evolutionary optimization algorithms have been used to implement the mathematical model to reduce the computational time required to attain the optimal solution.

Outlines the development of mechanical transmission elements used to drive industrial robots. Examines the performance requirements for precision gears and actuators, concentrating on harmonic drive reduction gearing and the key features which make it superior to conventional transmissions. Concludes that the unique features of the new harmonic drives gears will assist in the realization of completely new robot concepts and that to enable this to happen the process of continuous product development must be on‐going.

This paper aims to analyse the longitudinal performative effects of accounting, focusing on how accounting shapes the stability/instability of economic frames over time.

To explore the performative effects of accounting over time, a longitudinal case study narrates the transformation of a large, listed manufacturing company's financial strategy over 20 years. Using extensive document collection, the authors trace the shift from an “industrial” frame to a “shareholder value” frame in the mid-1990s, followed by the gradual entrenchment of this shareholder value frame until its decline in the wake of the financial crisis in 2008.

Our findings show how accounting has different performative temporalities, capable of precipitating sudden shifts between different economic frames and stabilising an ever-more entrenched and narrowly defined enactment of a specific frame. We conceptualise these different temporalities as performative moments and performative momentum respectively, explaining how accounting produces these performative effects over time. Moreover, in contrast to extant accounting research, the authors provide insight into the performative role of accounting not only in contested but also “cold” situations marked by consensus regarding the overarching economic frame.

Our paper draws attention to the longitudinal performative effects of accounting. In particular, the analysis of how accounting entrenches and refines economic frames over time adds to prior research, which has focused mainly on the contestation and instability of framing processes.

This paper aims to examine the interest rate risk management (IRRM) practices of UK‐listed companies. In particular, it examines the significance of interest rate risk (IRR) to these companies as well as the risk management practices adopted, including: the methods used to assess the level of IRR and the types of interest rate forecasts used in the process; derivatives activity; and corporate governance, reporting and control.

A series of semi‐structured interviews was conducted with the treasurers of ten UK companies in order to provide an in‐depth analysis of IRRM.

The results of this research suggest that IRR is important to UK companies and that their IRR hedging strategies are geared towards managing shareholder considerations and protecting banking covenants and corporate credit ratings. Moreover, companies rely extensively on financial derivatives to manage their IRR although their corporate governance practices relating to derivatives usage, in some instances, are lacking. Finally, there was a mixed response in relation to the implications of International Accounting Standard (IAS) 39; while some companies fear that the new standard may curb managerial practices, others are in favour of the more stringent reporting requirements.

The research indicates that IRRM is important to UK companies, and especially so for firms that have loan covenants in place. Thus, the interest rate decisions of the Bank of England will have a major effect on UK industry. The study also suggests that the implementation of IAS 39 may have unanticipated consequences on the risk management behaviour of UK firms as the possible reduction in the use of options and exchange‐traded products may result in less efficient IRRM within companies. Finally, the research suggests that corporate governance practices relating to financial risk management need to be improved.

The use of an interview‐based approach facilitates an investigation of the IRRM practices of companies on an individual basis rather than the aggregated analysis offered by most studies in the area. In addition, the paper addresses the more qualitative aspects of IRRM, such as the form and significance of IRR, IRR policy and strategy, and the use of derivative instruments.

The purpose of this paper is to inspect whether bank‐specific and macro‐economic determinants influence Islamic banks' profitability in the selected countries of different regions.

In order to achieve the study objective and to answer the question, the balanced panel data regression model has been used. Bank level data is used and this study examines the alternative measures ROA and ROE as a bank‐specific function and macro‐economic determinants.

The study results signify that banks with larger assets size and with efficient management lead to greater return on assets.

The paper shows that management efficiency regarding operating expenses positively and significantly affects the banks' profitability.

This paper seeks to examine the long‐run financial and return performance of UK companies which are grouped according to whether or not they have changed their dividends and earnings. Prior research has been conducted using US data and they are limited to extreme dividend changes such as dividend initiations and omissions. They have also arrived at contradicting results; some report a drift in performance, while others document evidence of mean reversion in performance. The current paper hopes to resolve this conflict using data for a large sample of UK firms which disclosed more general changes in dividends and earnings.

The aims of the paper are addressed using a stock market‐based study of share price performance and a detailed analysis of company performance based on financial ratios. These analyses are conducted from five years before to five years after the announcement of dividend/earnings news.

At the time of the announcements, share returns tend to be positive (negative) where companies have increased (decreased) the dividend and earnings. There is also evidence to suggest that the stock market has anticipated some of this news in the preceding 12 months. However, the dividend/earnings news does not appear to act as a signal of long‐term future company performance; companies which cut this dividend and reported lower earnings achieved the largest excess returns over the next five years. A similar mean‐revealing pattern existed in the financial ratios. Finally, most of the future long‐term share performance was attributable to the earnings rather than to the dividend news.

The main implication of this research is that current dividend/earnings news is not a good guide to future company performance. Indeed, it is these firms which cut their dividends along with reporting a reduction of earnings which achieve excellent results over a subsequent five‐year period. Of course, there are a number of limitations with the research; it draws on data from two previous studies, looks only at the UK and does not consider sophisticated models of investors' expectations with regard to dividend and earnings information.

The main contribution of this paper is the long‐run analysis of UK company performance following joint dividend‐earnings announcements. The analysis is comprehensive in that it considers both stock market performance as well as financial ratio performance for a period of up to five years following the dividend‐earnings news. Thus, it should be of interest to most UK investors as well as to financial managers with large quoted firms. Academics will also be interested in the results since they shed some light on an existing debate in the literature.

ROLLS‐ROYCE, LIMITED, have now been building aero‐engines for twenty‐one years, the original “Eagle” having been produced in 1914 when the late Sir Henry Royce was requested by the Admiralty to apply to the problem of aircraft motors his vast store of knowledge on the subject of internal combustion engines. It will be remembered that two Rolls‐Royce Eagle engines accomplished the first direct flight across the North Atlantic in 1919.

Besides other approaches, fuel savings in automotive applications and energy savings, in general, also require high‐efficiency gearboxes. Different approaches are shown regarding how to further improve gearbox efficiency. This paper aims to address these issues.

The paper takes the following approach: theoretical and experimental investigations of bearing arrangements and gear design as well as lubricant type and lubricant supply to the components lead to efficiency optimisation.

No‐load losses can be reduced, especially at low temperatures and part‐load conditions when using low‐viscosity oils with a high viscosity index and low oil immersion depth or low spray oil supply of the components. Bearing systems can be optimised when using more efficient systems than cross‐loading arrangements with high preload. Low‐loss gears can contribute substantially to load‐dependent power loss reduction in the gear mesh. Low‐friction oils are available for further reduction of gear and bearing mesh losses. All in all, a reduction of the gearbox losses in an average of 50 per cent is technically feasible.

Results from different projects of the authors and from the literature are combined to quantitatively evaluate the potential of power loss reduction in gearboxes.

An estimate of the fair rate of return on capital is a critical input into tariff regulation. A too high estimate will lead to high tariffs for consumers; a too low estimate will not provide adequate incentives for investment. The Airport Economic Regulatory Authority of India has issued a consultation paper for finalizing the norms and procedure for estimating the fair rate of return. It now needs to reconcile the differing view and approaches of different stakeholders.