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The purpose of this paper is to propose a method of optimal control of current commutation of switched reluctance motor drive.

The problem of optimal current commutation control is solved by off‐line selection of switching‐on and switching‐off angles. Selection of optimal values of angles is provided on computer model of the drive with help of particle swarm optimisation method. The optimal angle values are detected as functions of phase current and rotor speed. These calculated optimal values are stored in microcomputer control system memory in form of two‐input look‐up tables. The results are validated on laboratory set up.

Three different criteria of optimal control, which are taken into account: the maximum electromagnetic torque for given reference current, the maximum ratio of electromagnetic torque to root mean square value of phase current and the minimum electromagnetic torque ripples, gave a good results validated by simulation and experimental investigations.

A simple control method is proposed to optimise switched reluctance motors drive behaviour. Such an approach can be recommended for practical implementations.

The off‐line optimisation of switching angles, which is realised on computer model, is sufficient to obtain a good control effect.

Discusses the 27 papers in ISEF 1999 Proceedings on the subject of electromagnetisms. States the groups of papers cover such subjects within the discipline as: induction machines; reluctance motors; PM motors; transformers and reactors; and special problems and applications. Debates all of these in great detail and itemizes each with greater in‐depth discussion of the various technical applications and areas. Concludes that the recommendations made should be adhered to.

Gives introductory remarks about chapter 1 of this group of 31 papers, from ISEF 1999 Proceedings, in the methodologies for field analysis, in the electromagnetic community. Observes that computer package implementation theory contributes to clarification. Discusses the areas covered by some of the papers ‐ such as artificial intelligence using fuzzy logic. Includes applications such as permanent magnets and looks at eddy current problems. States the finite element method is currently the most popular method used for field computation. Closes by pointing out the amalgam of topics.

This study examines the value relevance of recognised and disclosed revaluations of land and buildings for a large sample of Australian firms from 1993 through 1997. In contrast to prior research, we control for risk and cyclical effects and find no difference between recognised and disclosed revaluations, using yearly‐cross‐sectional and pooled regressions and using both market and non‐market dependent variables. We also find only weak evidence that revaluations of recognised and disclosed land and buildings are value relevant.

During the 1990s the value to an intending professional accountant of undertaking a period of liberal (general) studies was promoted internationally by a number of individuals and organisations, including the International Federation of Accountants (IFAC) and the New Zealand Institute of Chartered Accountants (the “Institute”). The Institute significantly changed its admissions policy for Chartered Accountants in 1996 and one change was to require four years of degree level study with a compulsory liberal studies component. This study surveys the perceptions of New Zealand accounting practitioners on the impact of this compulsory liberal component. The results of this study demonstrate that there is little support from accounting practitioners for IFAC’s claim that liberal education “can contribute significantly to the acquisition of professional skills”, including intellectual, personal and communication skills. In addition, the majority of respondents did not perceive any improvements in the professional skills of the staff that had qualified under the Institute’s current admissions policy. However, any perceived improvements were mainly attributed to the Institute’s admissions policy change. Notwithstanding the lack of support for the assertion that liberal education develops professional skills, there is a strong belief by respondents in the value of liberal education for intending professional accountants.

The purpose of this paper is to investigate whether the political setting (civil war versus temporary truce) in a country has an influence on firms' current narrative, visual, and numerical intellectual capital disclosure being included in the current market value of equity.

Using content analysis for data generation, this study identifies narrative, visual, and numerical intellectual capital disclosure in firms' annual reports. Financial data were obtained from firms' annual reports and the stock exchange. Fixed effect panel regression was conducted separately for the civil war period and temporary truce period.

The paper finds that during the period entirely beset by civil war, the current market value of equity includes net book value and current earnings only, and does not include narrative, visual, or numerical intellectual capital disclosure. During the period of temporary truce, the current market value of equity includes net book value, current earnings, and narrative disclosure, but not visual or numerical intellectual capital disclosure.

The findings provide insights into the effectiveness of disclosure strategies in politically unstable environments.

This study analyses the disclosure strategies in a civil war and temporary truce context.

Part 2 of this article appeared in the February issue. Basic principles were explained, followed by a description with illustrations of the various methods which could be used to produce flux in the required direction. This part will deal mainly with the values used in magnetic particle testing, the different current wave forms with a discussion on the advantages and limitation of each. A short abbreviated table of values used in various standards and codes is also included for comparison.

Flying‐capacitor multilevel converters (FCC) need a passive or active regulation of the capacitor voltages. Recently the trend is towards active control, often implemented separately from the current control. The advantages of a true multi‐variable control sparked the interest to apply Model Based Predictive Control (MBPC) for FCC. In this paper an objective analysis method to evaluate the effects of several design choices is presented. The effects of the weight factor selection, model simplification, and prediction horizon expansion for MBPC of a 3‐level FCC are analyzed in a systematical way.

The analysis is mainly based on the mean square error (MSE) of current and capacitor voltage. The results are analysed for different lengths of the prediction horizon and for a wide range of weight factor values. Similarly the effect of a model simplification, neglecting the neutral point voltage, is studied when implementing MBPC for FCCs while considering the computational aspects. Validation of the simulation results is done by experiments on an FPGA‐based setup.

Including the effect of the neutral point voltage considerably increases the current control quality and a much wider range of good values for the weight factor exists. As this good range is not critically dependent on the current amplitude it is possible to select one weight factor value for all operating points. Furthermore, it is concluded that increasing the prediction horizon increases the computational load without improving the control quality.

The effects of increasing the prediction horizon when including other controlled variables is to be investigated, as well as the robustness to modeling errors. The MSE analysis methodology is very suitable for this further research.

For practitioners of MBPC in power electronics the paper proves that by means of simulations and the MSE one value for weight factor can be chosen for all operating points. The paper clearly shows that a practical implementation is feasible and demonstrates that neglecting the neutral point voltage is not good practice.

The MSE‐based analysis is shown to be a systematical and unbiased methodology to evaluate the effects of design choices. The results from this analysis can be directly applied in practical setups.

Prior literature suggests that stock prices lead earnings in reflecting value-relevant information because accounting income incorporates information discretely to satisfy recognition principles while stock prices incorporate it continuously. The purpose of this paper is to derive an analytical model that relates the time lag of earnings to the incremental informativeness of future anticipated earnings in equity prices after controlling for current realized earnings.

This study models the extent to which forward-looking information about future earnings is capitalized into current stock returns. Specifically, this study derives an analytical future earnings response coefficient (FERC) model that regresses current stock returns on both current and future earnings surprises, and examines the properties of the regression coefficients on current earnings (i.e. current earnings response coefficient, CERC) and future earnings (i.e. FERC).

The analytical FERC model shows that the pricing coefficient on future earnings (FERC) is positive in the presence of stock prices leading earnings. More importantly, the pricing coefficient on future earnings (FERC) increases with the recognition lag, but the pricing coefficient on current earnings (CERC) decreases with the lag. The results suggest that recognition principles that intend to enhance the reliability of earnings inadvertently lower the timeliness of earnings and, thus, shift the investors’ demand for value-relevant information from current realized earnings to future anticipated earnings.

This study makes two major contributions. First, it fills the gap between the lack of an analytical model and the abundance of empirical findings in previous FERC studies. As the recognition lag of earnings increases, stock investors shift the pricing weight on value-relevant information from current realized earnings to future anticipated earnings. Second, it provides support for the validity of the FERC model as an empirical model that examines the lack of earnings timeliness. As the timeliness of earnings relative to stock prices declines, the FERC increases but the CERC decreases.

Recent studies on the securities market’s differential pricing of earnings components have shown that cash flow from operations is more highly valued than total accruals and that moderate cash flow from operations has higher valuation than extreme total accruals. An interesting question that follows is whether these findings hold regarding the differential valuations of cash flow and current accruals. This study aims to extend prior research by addressing this issue in two ways. First, the authors examine the incremental information content of cash flow from operations beyond working capital from operations. Second, the authors assess the effect of extreme working capital from operations on the incremental information content of cash flow from operations. This study aims to extend prior research by addressing this issue in two ways.

This study adopts market-based accounting research to test its hypotheses and to achieve its objectives. Specifically, this study uses statistical associations between accounting data and stock returns to examine the incremental information content (value relevance) of cash flow and working capital from operations and the effect of extreme working capital from operations on the incremental information content of cash flow.

The results show that cash flow from operations is not more highly valued than current accruals (both being valued equivalently). However, moderate cash flow from operations has higher valuation than extreme current accruals (each is valued differently). Overall, these research findings indicate that cash flow becomes more important for valuation as accruals get “extreme”.

As accruals are unlikely to persist to be permanent across the years, these results can be interpreted as indicating that cash flow and accruals information are used jointly by investors, with one being more important than the other depending on the relative “extremeness” of each. Therefore, both are of value to the investor and both should be reported.

The paper contributes to the UK research on determining the preferred level of disaggregation of earnings components, i.e. operating cash flow, current accruals and non-current accruals. This would help investors to improve their investment and credit decisions.