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The purpose of this paper is to propose a new simplified numerical model, based on a very compact semi-empirical formulation, able to simulate the fluid dynamics behaviors of an electrohydraulic servovalve taking into account several effects due to valve geometry (e.g. flow leakage between spool and sleeve) and operating conditions (e.g. variable supply pressure or water hammer).

The proposed model simulates the valve performance through a simplified representation, deriving from the linearized approach based on pressure and flow gains, but able to evaluate the mutual interaction between boundary conditions, pressure saturation and leak assessment. Its performance was evaluated comparing with other fluid dynamics numerical models (a detailed physics-based high-fidelity one and other simplified models available in the literature).

Although still showing some limitations attributable to its simplified formulation, the proposed model overcomes several deficiencies typical of the most common fluid dynamic models available in the literature, describing the water hammer and the nonlinear dependence of the delivery differential pressure with the spool displacement.

Although still based on a simplified formulation with reduced computational costs, the proposed model introduces a new nonlinear approach that, approximating with suitable precision the pressure-flow fluid dynamic characteristic of a servovalve, overcomes the shortcomings typical of such models.

In the light of the risks involved in related party transactions, transparent disclosure is particularly important. The impact of related party transactions is relevant for all types of company, but there is greater complexity in business groups where they can be easier to hide. Focusing on business groups, this study aims to analyze the accuracy and transparency of related party transaction information, its understandability, compliance with legislation and comparability. It also examines whether shareholders can be fully informed of all related party transactions by reading only the consolidated financial statement.

Three case studies are used. The units of analysis are three corporate groups in which the parent company is listed on the Milan Stock Exchange as of 1 July 2015. The authors use two different sets of information. The first is secondary data from company procedures, annual reports and other official documents. They analyzed the separate financial statement of each firm, including the separate financial statement of the parent company and compared all relevant information from the consolidated financial statement and the separate financial statement. The second set is primary data from face-to-face semi-structured interviews and observation.

This study underlines that there is no requirement for a specific classification of related party transactions disclosure, and as a consequence, it is not possible to compare information. An unambiguous framework for disclosure, established by regulation or legislation, for use by companies supplying related party transactions information would be useful.

The results offer possible recommendations for regulators to improve presentation of related party transaction information without increasing the amount of information required.

MISS ANNE SHAW's presence on the platform at the annual general meeting of the Management Consultants Association was a solid assurance that work study still lies within its scope. The initial impression was weakened, however, when the chairman, Mr. D. J. Nicolson, mentioned that the bulk of consultancy work was no longer concerned with work study. Instead, it gave more than half its attention to policymaking and the broad aspects of organising financial, manufacturing and marketing resources.

It has often been said that a great part of the strength of Aslib lies in the fact that it brings together those whose experience has been gained in many widely differing fields but who have a common interest in the means by which information may be collected and disseminated to the greatest advantage. Lists of its members have, therefore, a more than ordinary value since they present, in miniature, a cross‐section of institutions and individuals who share this special interest.