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As well known, in the finite element method, the calculation and the location of the elements of the matrix C of the coefficients requires a lot of calculation times and memory employment especially for 3D problems. Besides, once the matrix C is properly filled, the solution of the system of linear equations is computationally expensive.

The paper consists of two parts. In the first part, to quickly calculate and store only the non‐null terms of the matrix of the system, a geometrical analysis on three‐dimensional domains has been carried out. The second part of the paper deals with the solution of the system of linear equations and proposes a procedure for increasing the solution speed: the traditional method of the conjugate gradient is hybridized with an adequate genetic algorithm (Genetic Conjugate Gradient).

The proposed geometrical procedure allows us to calculate the non‐null terms and their location within the matrix C by simple recursive formulas. The results concerning the genetic conjugate gradient show that the convergence to the solution of the linear system is obtained in a much smaller number iterations and the calculation time is also significantly decreased.

The approach proposed to analyze the geometrical space has been turned out to be very useful in terms of memory saving and computational cost. The genetic conjugate gradient is an original hybrid method to solve large scale problems quicker than the traditional conjugate gradient. An application of the method has been shown for current fields generated by grounding electrodes.

This paper aims to design an algorithm able to locate all the possible dangerous areas generated by the leaking of a fault current in a grounding system (i.e. the areas where the limits of the technical standards are not respected) and thus locate, inside each area, the point which takes locally the maximum value of touch voltage.

A fast evolutionary‐deterministic algorithm to solve constrained multimodal optimization problems is proposed. The algorithm is composed by three algorithmic blocks: a Quasi Genetic Algorithm to find a population of feasible solutions, a Fitness Sharing Selection to choose a subpopulation of feasible and fitter solutions having high diversity, a Hooke‐Jeeves Algorithm to find all the global and local feasible maxima.

The proposed algorithm has been successfully applied to various current field (i.e. to many shapes of grounding grids) problems to find the dangerous values of touch voltages generated by various grounding systems having any shape and it has turned out to be fast and reliable.

For this kind of problems, in fact, there is a lack, in literature, of multimodal optimization methods under safety constraints and the application of classical methods (e.g. genetic algorithms or deterministic methods) would be often inadequate since these methods are made so as to converge towards a single maximum point and so they unavoidably lose the information related to all the other possible maxima. On the contrary, a good application of the proposed allows the overcoming of these limits.

Sets out a method for determining the dangerous areas on the soil surface. The touch voltages are calculated by a Maxwell's subareas program. The search for the areas in which the touch voltages are dangerous is performed by a suitably modified genetic algorithm. The fitness is redefined so that the genetic algorithm does not lead directly to the only optimum solution, but to a certain number of solutions having pre‐arranged “goodness” characteristics. The algorithm has been called “quasi‐genetic” algorithm and has been successfully applied to various grounding systems.

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.

The more the rate of sub‐division of the grid into subareas is high, the more the Maxwell’s sub‐areas method of studying the current field generated by a grounding grid is accurate. In this paper the authors suggest a fuzzy approach applied to a horizontal cylindrical electrode which allows them to determine in advance the errors due to the different rates of subdivision.

All the algorithms introduced by the authors in their finite‐element computational program for studying fields easily and quickly are described in the paper. Moreover, an application of the analysis of the thermal field to a three‐phase transformer is proposed. This analysis gives a valid help to designing transformers having to provide services to satisfy some particular needs.

For a new technology-based firm, the ability to learn is crucial to their growth process. However, firms constantly face the challenge of maintaining the ambidexterity of two different learning activities, namely learning by exploiting existing competencies and learning through exploring new ones. The purpose of this study is to examine how small technology-based firms at incubators perform both activities. Using the index of network openness, we argue that firms perform ambidexterity by maintaining a balance between a high and low level of network openness. Our first hypothesis was constructed as firms pursuing explorative learning will develop a high level of network openness while those pursuing exploitative learning will develop a low level of network openness. In the second hypothesis, we argue that firms need to balance network openness. Developing too low level of network openness will not add more benefits as the cost for maintaining relationship increases. Similarly, developing too high level of openness may potentially hinder firms’ progress as firms face distractions and difficulties in maintaining a wide variety of relationships. Using the empirical data from new technology-based firms located at the Daresbury SIC, we confirm the hypotheses. The result also found a trend of a curvilinear relationship between network openness and the firms’ performance which confirm the second hypothesis. The overall findings have illustrated how a network has a positive impact on helping small and new technology-based firms perform learning ambidexterity.

Introduces the fourth and final chapter of the ISEF 1999 Proceedings by stating electric and magnetic fields are influenced, in a reciprocal way, by thermal and mechanical fields. Looks at the coupling of fields in a device or a system as a prescribed effect. Points out that there are 12 contributions included ‐ covering magnetic levitation or induction heating, superconducting devices and possible effects to the human body due to electric impressed fields.

The 15 years spanning from the end of the nineteenth century till the outbreak of the First World War formed, perhaps, the richest period in the history of Marxian economics. The main development between the time of Marx's writing and that of the German-Russian debates was the change in the competitive nature of the capitalist system. In the early stages of capitalism, the forces of competition created an imperative for capitalist firms to invest all their profits, or lose out in the competitive struggle to other firms which did. However, as large firms and oligopolistic structures emerged, the nature of competition changed, with price competition no longer the only form, leading to an erosion of this imperative, and an increase in capitalist consumption. Kalecki showed that, in this case, total profits were determined by capitalist's consumption and investment expenditures. The result, according to Kalecki, was a chronic tendency towards stagnation in capitalist economies. The long boom could be explained as ‘exports’ to a market external to the private sector, namely armaments and military expenditures.

Resurgent interest in the life and work of the Italian Cambridge economist Piero Sraffa is leading to New Directions in Sraffa Scholarship. This chapter introduces readers to some of these developments. First and perhaps foremost is the fact that as of September 2016 Sraffa’s archival material has been uploaded onto the website of the Wren Library, Trinity College, Cambridge University, as digital colour images; this chapter introduces readers to the history of these events. This history provides sharp relief on the extant debates over the role of the archival material in leading to the final publication of Production of Commodities by Means of Commodities, and readers are provided a brief sketch of these matters. The varied nature of Sraffa scholarship is demonstrated by the different aspects of Sraffa’s intellectual legacy which are developed and discussed in the various entries of our Symposium. The conclusion is reached that we are on the cusp of an exciting phase change of tremendous potential in Sraffa scholarship.