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A full consistent discretization scheme of the improved carrier density, momentum‐ and energy‐conservation equations is presented. The carrier heat flux as well as the convection and recombination terms are considered. The convection terms are averaged and then the differential constitutive relations of the current density and the energy flux are solved. The proposed discretization scheme generalizes the Scharfetter‐Gummel (S‐G) difference approximation to the generalized hydrodynamic model (HDM). On the basis of this scheme the hydrodynamic equations (HDE's) are solved for both electrons and holes. The transport of hot carriers in the p‐i‐n diode is investigated over a large scale of biasing values. The electric field distribution is not severely purturbed by the hot electron effects up to the medium biasing range. However, the minority carrier distribution is significantly affected by the carrier temperature‐gradients near the space‐charge‐regions. The minority carriers that are diffused to the edge of depleted regions are heated and if the carrier temperature gradient is sufficiently strong they diffuse back to the neutral cold region rather than to be captured by the electric field as known from the standard DDM theory.

Post-socialist transition affected rural gender regimes in multiple ways. This chapter focuses on how changes in the distribution of reproductive responsibilities between state, market and family affected the gender division of childcare and household labour in the newly established family farms and, as a result, affected the overall rural gender regime. The gender division of family care and household labour informs the genderedness of social and economic citizenship as it determines men's and women's opportunities to participate in productive work and their relations of economic and social dependency.¹ Local (in this case rural) care regimes are formed not only by the conditions of the hegemonic welfare state, but also by the specific conditions characterizing the locality, the local class, age, ethnicity and gender relations.

Most of the proposed decision aid methods provide the user only with a prescriptive approach (quantitative analysis) without any descriptive approach (qualitative analysis). It is therefore not possible to justify and recommend ways of improvement. The purpose of this paper is to introduce visualization techniques to complement prescriptive approaches.

Visual techniques have been developed for the FlowSort sorting method, namely the FS‐GAIA and stacked bar diagrams.

It is found that with visual techniques, fine details can be captured, e.g. detection of incomparability (with FS‐GAIA) and the composition of a score (with stacked bar diagrams).

In the future, it is expected that other multi‐criteria decision methods will be complemented by prescriptive approaches.

A real case study is introduced in order to illustrate the practicality of the visual techniques. In this paper, the innovation performances of small and medium enterprises from the French Lorraine region are assessed.

It is expected that the quality of the decisions taken are improved because of being better informed.

The paper, using a real case study, provides important new tools to enhance decision quality.

EVERY librarian in his inmost heart dislikes newspapers. He regards them as bad literature; attractors of undesirable readers; a drain upon the limited resources of the library; and a target against which the detractors of public libraries are constantly battering. From the standpoint of the librarian, newspapers are the most expensive and least productive articles stocked by a library, and their lavish provision is, perhaps, the most costly method of purchasing waste‐paper ever devised. Pressure of circumstances and local conditions combine, however, to muzzle the average librarian, and the consequence is that a perfectly honest and outspoken discussion of the newspaper question is very rarely seen. In these circumstances, an attempt to marshal the arguments for and against the newspaper, together with some account of a successful practical experiment at limitation, may prove interesting to readers of this magazine.

THE Programme of the Library Association Conference which reached us on April 22nd is one of much interest. Every year increases the difficulty of providing matter which has such appeal that members can say at the close that the time has been spent profitably. The pre‐print of the papers—a rather incomplete affair—raises the thought that Conference time could be better used than in discussions on such “Research Committee” matters as library vans and temporary buildings, excellent as we admit the enquiries and results of them to be. Yet this reflection is accompanied by the certainty that there have been few conferences which have not contributed something of material use to every participator and we still hold the view that more is learned in “a week at one than in months of hermit‐like seclusion.” That last quotation was written in the first edition of Brown's Manual and is valid to this day. Our representatives will write impressions after the event, not by way of detailed report, but as endeavouring to sum up what, if anything, material has been achieved. The report published by the Association usually gives the papers in extenso, but we wish its issue could be delayed long enough to provide more informative records of the discussions. As the best contributions occasionally come from the floor, the bare‐bones notes of the names of speakers and almost telegram‐like utterances they are supposed to have made, which have been the customary report, could be greatly improved.

This paper aims to focus on the trade-off between losses and converter cost.

The continual development of power electronic converters, for a wide range of applications such as renewable energy systems (interfacing photovoltaic panels via power converters), is characterized by the requirements for higher efficiency and lower production costs. To achieve such challenging objectives, a computer-aided design optimization based on genetic algorithms is developed in Matlab environment. The elitist non-dominated sorting genetic algorithm is used to perform search and optimization, whereas averaged models are used to estimate power losses in different semiconductors devices. The design problem requires minimizing the losses and cost of the boost converter under electrical constraints. The optimization variables are, as for them, the switching frequency, the boost inductor, the DC capacitor and the types of semiconductor devices (IGBT and MOSFET). It should be pointed out that boost topology is considered in this paper but the proposed methodology is easily applicable to other topologies.

The results show that such design methodology for DC-DC converters presents several advantages. In particular, it proposes to the designer a set of solutions – as an alternative of a single one – so that the authors can choose a posteriori the adequate solution for the application under consideration. This then allows the possibility of finding the best design among all the available choices. Furthermore, the design values for the selected solution were obtainable components.

The authors focus on the general aspect of the discrete optimization approach proposed here. It can also be used by power electronics designers with the help of additional constraints in accordance with their specific applications. Furthermore, the use of such non-ideal average models with the multi-objective optimization is the original contribution of the paper and it has not been suggested so far.

Doubly fed induction generator (DFIG) is widely used in wind energy conversion systems and it can operate with other primary movers. The purpose of this paper is to focus on the standalone operation of DFIG which may expand the area of possible applications and increase capabilities of the generation system in terms of power quality.

Synthesis of the control method was preceded by analysis of mathematical model of the machine. The control method based on the negative sequence and high harmonics extraction has been developed and verified in the laboratory unit. Control of the fundamental frequency component uses neither rotor speed nor position sensors.

The original method allows to compensate negative sequence and high harmonics of the generated voltage. At the same time, due to the active filtering capability of the grid side converter, the stator phase current shape is close to sine wave. Thus, it is seen by the machine as a linear load, what eliminates the electromagnetic torque ripples.

The system and control method can be applied in variable speed generation systems, e.g. wind turbines or diesel engines operating in the standalone mode.

Although the selective compensation of negative sequence and harmonics are known in the literature, until now the methods have been verified for the system with a rotor position sensor. Moreover, the stator current feed-forward improving the transient properties, as well as results of transient states caused by the load step change, have not been proposed in publications.

An electrochemical impedance spectroscopy technique based on an equivalent circuit used for the evaluation of metallic substratum/organic coating/electrolyte systems as well as the importance of each parameter and the way to calculate it is analysed. It is emphasised that the classical semi circumference in the complex plot, which describes the response of a parallel RC circuit, is not real axis centred. This fact makes it necessary to consider the organic film and electrochemical double layer capacitance as pseudo‐capacitances which depend on a fractional power of the frequency. Starting from mathematical relationships over the total impedance algorithms based on the least squares methods are proposed to fit experimental data requiring less processing time than iterative techniques. The methodology is described analysing the charge transfer resistance, ionic resistance and dielectric capacitance variation at increasing immersion times for naval steel/chlorinated rubber (with different PVC)/artificial sea water systems. Parameters thus obtained correlate well with the naval steel/organic coating deterioration with time, also determined by using corrosion potential measurements and visual assessment.

This paper aims to map literature about innovation capabilities (IC) taking into consideration industrial clusters to propose a conceptual framework that synthetizes the main factors and subfactors responsible for ICs; in addition, the paper also proposes a research agenda.

A systematic literature review (SLR) was performed; academic papers were analyzed qualitatively and quantitatively.

The authors provide a descriptive analysis followed by a thematic synthesis, in which we present 05 enablers and 20 critical factors (CF) of IC in clusters. The proposed framework emphasizes what needs to be done or improved to increase IC in cluster-based companies. Based on this systematic review and the framework proposed, the authors identified opportunities for future research.

The enablers and CF identified through SLR were not validated empirically. Therefore, future studies on the current topic are required to validate the framework by investigating which factors are more relevant to cluster-based companies that intend to improve their innovative performance.

The present findings have important implications for the identification of the factors and subfactors that may contribute to the development of IC, which may help managers and decision-makers in recognizing which factors are the most responsible for business innovation.

The paper identifies enablers related to the development of IC in industrial cluster and presents a research agenda. The framework represents a guideline for companies to achieve better innovation performance.