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A quantitative method for the estimation of the discrete transition matrix is developed for the periodic time‐varying system of state differential equations governing electrical synchronous machine behaviour. The approach allows the eigensystem of this transition matrix to be calculated to an arbitrary accuracy without significant added computational burden by using modal structural properties of the state‐space equations.

The implementation of hierarchic agglomerative methods of cluster anlaysis for large datasets is very demanding of computational resources when implemented on conventional computers. The ICL Distributed Array Processor (DAP) allows many of the scanning and matching operations required in clustering to be carried out in parallel. Experiments are described using the single linkage and Ward's hierarchical agglomerative clustering methods on both real and simulated datasets. Clustering runs on the DAP are compared with the most efficient algorithms currently available implemented on an IBM 3083 BX. The DAP is found to be 2.9–7.9 times as fast as the IBM, the exact degree of speed‐up depending on the size of the dataset, the clustering method, and the serial clustering algorithm that is used. An analysis of the cycle times of the two machines is presented which suggests that further, very substantial speed‐ups could be obtained from array processors of this type if they were to be based on more powerful processing elements.

This paper examines the impact on the accounting profession of those aspects of new types of non‐traditional reporting which are actually used in practice. Empirical evidence about data collection and reporting in some organisations shows that the current scope of mainstream accounting may be too narrow. Drawing especially on environmental accounting initiatives, the paper discusses where the boundaries of accounting and annual reporting are currently set, and whether the accounting profession can respond proactively to push the boundaries of corporate reporting to reflect performance in more all‐embracing ways.

The purpose of this paper is to examine the impact of auditor switching on audit fee discounting in Iran. The increased competition in the Iranian audit market following audit market liberalization in 2001 has resulted in a rapid increase in auditor switching and reduces the relative bargaining power of auditors compared to the clients. It is expected that auditor switching results in fee discounting because the relative bargaining power of an auditor (client) is likely to be at the minimum (maximum) point during the initial period of engagement. Since the increased bargaining power of a client in initial year seems to be different in the case of different type of auditor switching (from a state auditor to a private and from a private auditor to another), the magnitude of fee discounting is expected to be different.

The objective is tested using a sample of 1,022 firm-year observations between 2001 and 2010. This study applies the multivariate regression model using the first difference specification of audit fee as a dependent variable.

Multivariate analysis reveals that auditor switching results in 14 percent of fee discounting. In addition, the results show that 18 and 13 percent of fees discounting during the initial year of engagement arise from cases of auditor switching involving a change from state auditors to private auditors, and a change from one private auditor to another, respectively. The findings support bargaining power view explanation in relation to audit fees discounting in initial year engagement.

This study is the first to examine the impact of auditor switching (and analyzed different types of auditor switching) on audit fee discounting using the bargaining power view.

The purpose of this paper is to investigate the enhancement of the performance of bubble absorber using hybrid nanofluid as a cooled NH₃/H₂O absorption system to reduce their size and to find the best fitting model. A numerical model for ammonia-water bubble absorber was developed to show the influence of operating conditions and design parameters on the absorber performance.

A finite difference numerical method is used to solve the numerical model. The model is subjected to the inlet conditions of liquid, vapor and coolant flow regimes. The absorber modeling was divided into small elements along the absorber length.

The model proposed is validated with previously published works. Then agreement between the both is considered as good.

Numerical results/The use of hybrid nanofluids.

The results showed that the hybrid nanofluid is the best cooling medium. Very high heat transfer rates are obtained because of the high thermal conductivity and specific heat of hybrid nanofluid, and consequently, the absorber size decreases. It was also found that the absorber thermal load and the mass absorption flux increase with increasing of solid volume fraction. Also, the existence of an optimal absorber length was revealed, required for complete absorption when using hybrid nanofluid as a cooling medium. It is recommended that using hybrid nanofluid to remove the heat from the absorber is the best candidate for NH₃/H₂O absorption performance enhancement.

This paper aims to investigate the performance and working fluids screening for an ejector refrigeration cycle (ERC) activated by solar energy. Several common and new hydrofluorocarbons, hydrocarbons, hydrofluoroolefins and hydrofluoroethers are proposed as refrigerants for the ERC to determine the most appropriate one.

The ejector performance is characterized by the ejector area ratio (EAR) and entrainment ratio (ω), while the cycle performance is described by the coefficient of performance (COP). The influences of many working parameters like the evaporator, condenser and generator temperatures on the ejector and cycle performances are investigated for all candidates as well.

The results indicate that the best ejector and cycle performances are attained with the highest critical temperature dry refrigerant, i.e. R601 under all studied working conditions. From the perspective of energy efficiency and environmental issues, R601 can be considered the most appropriate working fluid amongst all candidates. However, extra attention should be considered against its flammability. The maximum COP, the corresponding ω and the necessary EAR using R601 are 0.743, 1.02 and 15.5, respectively, with 25 ºC condenser temperature and the typical values for the rest operating conditions.

Many common and new hydrofluorocarbons, hydrocarbons, hydrofluoroolefins and hydrofluoroethers are suggested as working fluids for the ERC to determine the most appropriate one. The mixing process inside the ejector constant-area section is assumed constant-pressure process.

Although corporate social responsibility–corporate financial performance (CSR-CFP) research topics have been widely investigated, previous research has yet to examine the relationship between the specific dimension of CSR and CFP among Malaysian public-listed companies. Through literature review, it has been found that the CSR-CFP studies conducted in Malaysia have omitted the role of workplace diversity dimension in contribution to CFP. Failure to consider this variable may risk misrepresenting the relationship between CSR and CFP, thereby preclude consensus on the direction of the relationship between the variables. The purpose of this study is to investigate the relationship between individual CSR dimensions and CFP.

By using the CSR dimension disclosure-scoring method and cross-sectional data analysis, this research has conducted a content analysis on annual reports of the sample companies to evaluate the influence of CSR practices on companies’ profitability during 2015.

The results show that companies displaying CSR behavior are associated with higher CFP. That is to say, there is a positive relationship between CSR and CFP. However, the result has further revealed that the five CSR dimensions in isolation would differently associate with the two proxies of CFP.

To the best of the authors’ knowledge, this is the first study in Malaysia that considers workplace diversity issues as one of the dimensions of CSR. The findings will thus bring new insights into CSR application in Malaysia and its association with the CFP.

The purpose of this study is to empirically examine the effect of board multiple directorships and chief executive officer (CEO) characteristics on firm performance among nonfinancial firms listed on the Palestine Security Exchange (PSE) during the period from 2009 to 2016.

Based on 200 observations, this study utilizes panel data to examine the effect of the predictors on firm performance measured by return on assets. The analysis is repeated using the return on equity and two regression methods to evaluate the robustness of the main analysis (pooled regression, and backward stepwise regression analysis).

The results show that the “busyness” of a CEO reduces their effectiveness and is associated with losses in the companies where they are in charge. On the other hand, the results show that CEO tenure, CEO experience and CEO political connections have a positive effect on corporate performance.

This study is timely given that the practice of multiple directorships is widely common among firms in developing countries. Prior research in Palestine has not investigated the role of multiple directorships and the CEO characteristics on corporate outcomes. This study provides a picture of the potential benefits to firms, policymakers and professional bodies from considering CEO variables. The findings of such an examination can help them to set up suitable policies and enhance the role and the quality of the CEO in firms.

Driving cycle is an essential requirement to evaluate the exhaust emissions of various types of vehicles on the chassis dynamometer test. This study presents a real world comparison of the driving cycles of Edinburgh motorcycles in two world cities; Edinburgh in Scotland and Delhi in India. The two driving cycles (EMDC & DMDC) driving cycle (EMDC) that were was developed through the analysis of experimental data. This data was collected from trips on a number of routes in each city. In Edinburgh, five different routes between the home addresses in the surrounding areas and place of work at Edinburgh Napier University in Edinburgh were selected. In Delhi data were collected in East Delhi (Geeta Calony) to Central Delhi (Raisena Road). The data collected data was divided into two categories of urban and rural roads in the case of Edinburgh while it was only the urban route in Delhi.. Forty four trips were made on the five designated routes in both urban and rural areas and 12 trips were made in Delhi. The aims of the study were to assess the various parameters (i.e. motorcycle speed, cruise, accelerations and decelerations and percentage time spent in idling) and their statistical validity over total trip lengths for producing a real world EMDC in each of the two cities. The results show that EMDC in Edinburgh, the EMDC has a cycle length of 770 and 656 seconds for urban and rural trips, respectively, which was found more than ECE cycle length. Time spent in acceleration and deceleration modes were found to be significantly higher than any other driving cycle reported to date for motorcycles, reflecting a typical characteristic of the driving cycle in Edinburgh; this was presumably due to diverse driving conditions of motorcycles in the city. In Delhi on the other hand, the DMDC has a cycle length of 847.5 seconds for the urban trips, which higher than that of the EMDC length. The overall percentage time spent in acceleration in Delhi was higher than that of Edinburgh while the time spent in deceleration was lower in Delhi. The overall average speed in the case of Delhi was slightly higher than that of Edinburgh.