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A computer‐based expert system to help industry diagnose and solve corrosion problems has been developed by the U.K.'s National Physical Laboratory and Harwell's Metals Technology Centre. A prototype of the system has already been demonstrated widely in both the U.K. and the U.S. Other industrial sectors could well follow this lead and develop similar systems using expert systems. The main users of this system will be those associated with the metal, process and petrochemical industries. Such a system will be able to provide direct and rapid access to an extensive database on corrosion together with diagnostic and evaluation facilities for identifying and solving corrosion problems. The aim is to construct the full knowledge system and link it with the database in the same way as existing expert systems have been developed. One of the key elements of this system is the use of STATUS, the U.K.'s Harwell information storage and retrieval software package.

As part of an ongoing Ashridge Management College project, attempts to understand some of the reasons why there is a certain reluctance on the part of management educators to become too heavily involved in evaluation. In terms of its methodology, it is based on ten in‐depth, semistructured interviews with a sample of course tutors across a broad range of subject disciplines. Begins by outlining the emerging major themes from the perspective of the provider. Then goes on to discuss an evaluation system, adapted from the literature, which is intended to be viewed as organic, meaning that it is, intentionally made up of systematically interrelated parts. Concludes by discussing the implications of applying such a model to the emerging major themes.

The Management Charter Initiative (MCI) has now been in existence for several years. Its major objective is to promote the notion of “competency” and facilitate the introduction of a list of generic management standards into British organizations. In the light of the debate which this movement has provoked, attempts to summarize the major conceptual issues. Takes a big picture overview of the major advantages, disadvantages and “grey” areas as they are perceived by British management generally (i.e. organizations and academia). As far as possible, it is a balanced review, which it is hoped will assist human resource practitioners in the area of strategy formulation.

Proposes a framework for gaining a greater understanding of all types of managerial learning which builds upon Gregory Bateson′s (1973) notions of levels of learning. Goes on to discuss a major emergent issue, which has implications for the everyday realities of course content and design, namely a cyclical view of the learning process. As a means of grounding theory in reality, concludes by exploring the rudiments of a particular Ashridge course, which uses this framework extensively to guide its development. Ultimately, the course is guided by the notion of “individually tailored learning”.

Nelco were pleased to announce the appointment of Mr George Grant to the position of Sales Manager from June 1st 1990. Mr Grant, who has considerable stature in the industry and brings a wealth of experience to Nelco from his previous 13 years with Gould Foil Division and more recently as Sales Director with GTS Flexible Materials, will report to Mr Charles Carter, President European Operations.

Proposes a framework for gaining a greater understanding of all types of managerial learning, which builds on Bateson′s notion of levels of learning, which provides an ideal context in which to position the range of views expressed by the management tutors. Reveals that their assumptions and beliefs about learning and teaching tend to be guided by the essential nature of their respective subject discipline, which revolves around the notion of “hard” and “soft” disciplines and, hence, provides a rationale for teaching different types of learning and affects course content and design. Analyses the differences of approach by dissecting the learning process into a series of phases which are part of a cyclical model. Reveals large variations in the degree of importance placed on pre‐ and post‐course activity. Explores this model in greater depth by discussing a particular Ashridge general management programme, which uses this framework extensively to guide its development. Concludes by suggesting that management educators should refrain from deluding both themselves and their clients that all tutors, from a variety of subject disciplines, share the same basic assumptions about learning. In fact, it is imperative that they do not share the same basic assumptions, if they are really serious about tailoring learning to individual client needs.

This paper aims to understand what leadership is and how it occurs within organizations.

Highlights four key principles which serve as a guiding template or frame of reference to help enhance managers' confidence and credibility and encourage strong leadership inside an organization.

Followers choose our leaders – leaders do not choose their followers. This kind of relationship and connection between people goes beyond the transactional (i.e. managers and their direct reports) and into the realm of the transformational.

The phenomenon we call leadership/followership is an episodic series of events intending significant change. So, to be clear, leadership does not reside in a person or even several persons; it resides in a dynamic and ever‐changing relationship among people.

Creating leadership energy is an inside job, the stimulus for it comes from inside an individual. It can come from inside any individual of any type. This sits in opposition to the view that there is a universal list of character traits which determines who becomes a leader in any culture or any industry.

A method has been developed for the solution of inverse heat diffusion problems to find the initial condition, boundary condition, and the source and sink function in the heat diffusion equation. The method has been used in the development of a source‐and‐sink method to find the boundary conditions in inverse Stefan problems. Green's functions have been used in the solution, and the problems are solved by using two approaches: a series solution approach, and a time incremental approach. Both can be used to find the boundary conditions without reliance on the flux information to be supplied at both sides of the interface. The methods are efficient in that they require less equations to be solved for the conditions. The numerical results have shown to be accurate, convergent, and stable. Most of all, the results do not degrade with time as in other time marching schemes reported in the literature. Algorithms can also be easily developed for the solution of the conditions.

This paper aims to propose a semi-analytical benchmarking framework for enthalpy-based methods used in problems involving phase change with latent heat. The benchmark is based on a class of semi-analytical solutions of spatially symmetric Stefan problems in an arbitrary spatial dimension. Via a public repository this study provides a finite element numerical code based on the FEniCS computational platform, which can be used to test and compare any method of choice with the (semi-)analytical solutions. As a particular demonstration, this paper uses the benchmark to test several standard temperature-based implementations of the enthalpy method and assesses their accuracy and stability with respect to the discretization parameters.

The class of spatially symmetric semi-analytical self-similar solutions to the Stefan problem is found for an arbitrary spatial dimension, connecting some of the known results in a unified manner, while providing the solutions’ existence and uniqueness. For two chosen standard semi-implicit temperature-based enthalpy methods, the numerical error assessment of the implementations is carried out in the finite element formulation of the problem. This paper compares the numerical approximations to the semi-analytical solutions and analyzes the influence of discretization parameters, as well as their interdependence. This study also compares accuracy of these methods with other traditional approach based on time-explicit treatment of the effective heat capacity with and without iterative correction.

This study shows that the quantitative comparison between the semi-analytical and numerical solutions of the symmetric Stefan problems can serve as a robust tool for identifying the optimal values of discretization parameters, both in terms of accuracy and stability. Moreover, this study concludes that, from the performance point of view, both of the semi-implicit implementations studied are equivalent, for optimal choice of discretization parameters, they outperform the effective heat capacity method with iterative correction in terms of accuracy, but, by contrast, they lose stability for subcritical thickness of the mushy region.

The proposed benchmark provides a versatile, accessible test bed for computational methods approximating multidimensional phase change problems. The supplemented numerical code can be directly used to test any method of choice against the semi-analytical solutions.

While the solutions of the symmetric Stefan problems for individual spatial dimensions can be found scattered across the literature, the unifying perspective on their derivation presented here has, to the best of the authors’ knowledge, been missing. The unified formulation in a general dimension can be used for the systematic construction of well-posed, reliable and genuinely multidimensional benchmark experiments.

The purpose of this paper is concerned with a reliable treatment of the classical Stephan problem. The Adomian decomposition method (ADM) is used to carry out the analysis, Moreover, the authors extend the work to examine the Stefan problem with variable latent heat. The study confirms the accuracy and efficiency of the employed method.

The new technique, as presented in this paper in extending the applicability of the ADM, has been shown to be very efficient for solving the Stefan problem.

The Stefan problem with variable latent heat was examined as well. The ADM was effectively used for analytic treatment of the Stefan problem with and without variable latent heat.

The paper presents a new solution algorithm for the Stefan problem.