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A two‐dimensional electromagnetic field model of a railway track and traction line is used to determine the equivalent track distributed transmission line parameters in the frequency range DC to 30kHz. The model is solved using the finite‐element method to find the minimum energy condition for two conditions: current excitation to obtain the resistance and inductance, and voltage excitation for the conductance and capacitance. The results have been confirmed using practical test data, and their application is illustrated in a time‐domain circuit simulation to model interference between power and signalling currents in a 750V DC electric railway.

dc electrified traction systems are a potential source of stray currents. The purpose of this paper is to evaluate the harmful effects (electrolytic corrosion) that an electrified railway has on nearby earth return circuits (e.g. pipelines).

The electric circuit approach, based on the earth return circuit theory, to model stray currents interference on extended structures is presented. An exact method of calculation is applicable to any dc railway system in which tracks can be represented by a single earth-return circuit (equivalent rail) with current energization. In the approximate method, the equivalent rail with current energization is modeled as a large multinode electrical equivalent circuit with lumped parameters. The circuit is a chain of basic circuits, which are equivalents of homogenous sections of the rail. The electrode kinetics (polarization phenomenon) is taken into account in the model developed.

Formulas in partially closed forms are derived applicable to the analysis of currents and potentials along a pipeline laid in the proximity with railway tracks. The attempt is undertaken, to incorporate the electrode kinetics into the simulation model in which the polarization phenomenon (Tafel equation) is modeled by a non-linear voltage source with source voltage being iteratively calculated. The polarization potential along the affected pipeline can be determined.

The pipeline electrochemical response (polarization behavior – non-linear phenomenon on the interface metal-soil electrolyte) to the dc stray currents interference is innovative incorporated into the simulation model with lumped parameters using the iterative process.

The aim of this paper is to present a reinforced version of structuration theory, known as strong structuration theory, set out in Stones as a disciplined approach to qualitative case study research in the organization, management and accounting fields. This framework challenges the belief held by certain critics that structuration theory cannot be used in substantive empirical research but is only a sensitising device or analytical tool.

A conceptual discussion is the approach of the paper.

The key concepts of strong structuration theory are outlined and then put in the context first of two attempts to apply the framework to empirical research and second of two recent papers which address theoretically informed qualitative research and the use of structuration theory in IT studies.

There are some limitations of this paper. The framework offered was not used to set the original research questions in the two case studies employed as these cases were conducted before the publication of Stones' book in 2005. Also, as weaknesses in the framework can best be assessed using empirical findings, a full evaluation cannot be carried out until such research is undertaken.

This paper draws on recent research and thinking in sociology that have yet to be brought into case studies in the fields of accounting and management in particular.

Cottage is a protein-rich food which is commonly consumed by people targeting weight reduction and athletes willing to eat whole-food instead of protein supplements. Yet out of common knowledge, the scientific community lacks solid evidences of the effect of the inclusion of cottage cheese in a diet. The purpose of this paper is to assess the evidences from scientific literature of the impact of inclusion of cottage cheese in a diet.

PubMed and Web of Science were searched for scientific literature dealing with “cottage cheese” and “diet.” There was no restriction regarding the type article type, date nor journal it is published in. References found to during the analysis of the articles extracted from database were also included. Studies search, screening and eligibility analysis were led in parallel by two independent reviewers.

This survey shows that cottage cheese is a good source of calcium (with 83 mg/100 g) – but not low fat cottage cheese because of its low vitamin S content (p < 0.001) –, a source of probiotic (1 serving providing the recommended dietary intake), a source of high quality proteins, reduces postprandial blood glucose level – healthy and type II diabetes subjects – (p < 0.05), is not linked to increased cardiovascular diseases nor cancer risks (p < 0.05).

Based on the findings reported in this review, the inclusion of cottage cheese in a diet can be advised for: women to build up calcium storage to fight osteoporosis; more generally calcium/vitamin D deficient subjects; athletes willing to increase their high-quality proteins intake through whole food consumption; dieters looking for low energy, high protein, high satiety food; untreated type II diabetes patients by reducing postprandial glucose level.

A new model able to describe the high frequency (HF) behaviour of the laminated cores of AC machines is proposed. The aim is to compute the external flux density of machine cores, corresponding to electromagnetic emissions in the HF range when the skin effect is predominant.

For high frequencies, the skin depth is much lower than the thickness of a lamination and the external flux density is determined using a new analytical model. The validity of this model is confirmed by measurements performed on a magnetic core representing a small part of a large machine and a finite element 3D simulation.

For high frequencies, the external flux density is computed considering an equivalent current layer flowing on the laminated core external surface. Eddy currents in the laminated core have a large influence on the current density in this current layer.

The new model proposed is valid when the skin depth is lower than half the thickness of a lamination.

The knowledge of the machine magnetic core behaviour in the frame of the HF electromagnetic emissions has practical applications for large AC machine maintenance such as the localization of partial discharges in the winding insulation. With this model, it is possible to analyse the information given by small magnetic sensors placed between the machine core and the external frame to solve all the insulation problems.

The new proposed model is able to establish a link between the electric HF phenomena in the windings of a working machine and the magnetic flux density outside the laminated core.

The purpose of this paper is to explore qualitative methodologies appropriate to a research project investigating the boundaries and scope of the information profession, with specific reference to the skills/knowledge base and concepts of “professionalism”.

Reviewed and critically evaluated here are social theory frameworks, focusing particularly on Structuration theory.

Strong Structuration Theory either singly or in combination with Social Identity Theory, appears to offer a sound methodology to explore concepts of change, conflict and professional identity, from both micro and macro perspectives.

Strong Structuration Theory stands as a powerful tool in discovering reconstituted “boundaries along which professions can build new strategies of legitimisation” and remake themselves.

This review provides a critical evaluation of some of the current methodologies available to help define professional expertise.

In this paper, I synthesize the prior psychology literature on ego depletion and apply this literature to an auditing setting. Ego depletion refers to a reduced desire or ability to use self-control in task performance due to using self-control on prior tasks. I focus on the likely causes and consequences of depletion in an auditing setting, as well as means of mitigating depletion and recovering self-control resources. While ego depletion theory is prevalent in the psychology literature, little is known about whether or how ego depletion affects professionals on meaningful task performance. As a result, this synthesis is aimed at stimulating future ego depletion research in accounting, and specifically auditing, by surveying existing literature and applying this literature to an auditing setting. Further, I develop 13 questions for future research to investigate. My synthesis reveals that ego depletion likely has a pervasive effect in an auditing setting, and can hinder auditors’ judgment and decision-making (JDM) quality. Therefore, this synthesis helps to provide a greater understanding of the impact of auditing tasks on individuals, and refines both auditor JDM and ego depletion theories.

Studies on the performance of agribusiness cooperatives in Brazil focus on economic and financial aspects. The purpose of this paper is to further delve into such studies by investigating which commonly measurable structural production factors (horizontal, vertical and lateral diversification; operating area; number of associates; and time in operation) have greater impacts on the financial performance of such cooperatives.

To achieve such a goal, a survey was conducted with a sampling pool divided by size (annual net revenues of US$ 50 million or higher), and the questionnaire was employed as a method of data collection. The sample was concentrated in the southern, south-eastern and mid-western regions of Brazil; classified by size; and deemed adequate after several adequacy tests.

The results were analysed using Spearman’s correlation, which showed that there were no significant correlations between the structural production factors considered in this study and the economic-financial performance of agricultural cooperatives, which leads to questions about the effectiveness of employing diversification strategies with a conjoint approach. Nonetheless, it was possible to identify several relationships not mentioned in the original hypotheses that might be addressed further in future studies.

The data obtained should be interpreted with caution because heteroscedasticity was detected. Although the cause could not be clearly identified, the presence of heteroscedasticity could mean that smaller and similar cooperatives present similar variation in their diversification and production base strategies.

This work sought to generate knowledge regarding operations management, which was achieved by demonstrating that production diversification in a dynamic and relevant economic sector, that is, agricultural cooperatives, is limited in terms of financial return when performed in an isolated mode. Hence, cooperatives’ production managers should take into account the totality of structural production factors during their planning activities.

Many farm producer organizations pursue growth and complexity in response to price volatility, industry consolidation and other external developments. Consequently, as ownership is dispersed and control is delegated, members may face increasing agency cost. In spite of the potential to impact performance and even survival, empirical attention to agency problems in farm producer organizations is limited. The purpose of this paper is to address the gap in the literature with an empirical study.

With survey responses from 365 farm producer organizations in the USA, the author uses a two-limit tobit model to estimate the relationships of six ownership and governance characteristics (i.e. board size, management size, director independence, manager independence, CEO independence and non-member ownership) to agency cost, which is proxied by the operating expense ratio.

While controlling for heterogeneity in scale and technology, the author finds positive relationships of board size, management size and CEO independence to agency cost. The novel result illustrates there is a significant cost to the adoption of non-traditional ownership and governance characteristics by farm producer organizations.

The presence of agency cost serves as motivation to farm producer organizations to implement new or adapt old agency mechanisms. One recommendation is to reconsider the payment structure of non-member CEOs. There may not be enough incentive to inspire an upstream bias, which is perhaps possible by linking CEO performance to price, patronage and member-oriented performance measurements.

Agency cost is rarely studied in relation to farm producer organizations. Recent contributions in the empirical literature lacked an explicit connection of ownership and governance characteristics to agency cost.