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The purpose of this paper is to devote the optimal substitution of slip rings through an inductive power transfer system for field winding supply of generators or motors with a wound rotor. By a rotational pot-core transformer approach, the rotor-side energizing of the excitation windings can be provided isolated and free of wear.

For design purpose, an analytical model of the inductive link and the compensation network elements is shown. Based on a pot-core transformer approach, possible types of compensation networks regarding motor-specific constraints were carried out and compared among themselves by parameter studies. The analytical parts of the model were subsequently validated with measured data of an appropriate core and accompanying FEM calculations. On the basis of an experimental prototype system, the approach has been tested both stationary and transient.

The publication exemplifies how a brushless excitation system for generators and motors can be inexpensively designed and implemented.

This paper systematically presents a comprehensive analytical approach for brushless excitation systems as well as a prototypical system. Compensation network elements regarding motor-specific constraints were carried out and compared among themselves by parameter studies.

Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely, innovative thought structures and attitudes have almost always forced economic institutions and modes of behaviour to adjust. We learn from the history of economic doctrines how a particular theory emerged and whether, and in which environment, it could take root. We can see how a school evolves out of a common methodological perception and similar techniques of analysis, and how it has to establish itself. The interaction between unresolved problems on the one hand, and the search for better solutions or explanations on the other, leads to a change in paradigma and to the formation of new lines of reasoning. As long as the real world is subject to progress and change scientific search for explanation must out of necessity continue.

The design of microwave circuits requires detailed knowledge on the electromagnetic properties of the transmission lines used. This can be obtained by applying Maxwell’s equations to a longitudinally homogeneous waveguide structure, which results in an eigenvalue problem for the propagation constant. Special attention is paid to the so‐called perfectly matched layer boundary conditions (PML). Using the finite integration technique we get an algebraic formulation. The finite volume of the PML introduces additional modes that are not an intrinsic property of the waveguide. In the presence of losses or absorbing boundary conditions the matrix of the eigenvalue problem is complex. A method which avoids the computation of all eigenvalues is presented in an effort to find the few propagating modes one is interested in. This method is an extension of a solver presented by the authors in a previous paper which analyses the lossless case. Using mapping relations between the planes of eigenvalues and propagation constants a strip in the complex plane is determined containing the desired propagation constants and some that correspond to the PML modes. In an additional step the PML modes are eliminated.The numerical effort of the presented method is reduced considerably compared to a full calculation of all eigenvalues.

After some introductory words about the preeminence of German accounting research during the first half of the 20th century, the paper offers a survey of the most important theories of accounts classes that still prevailed during the first two decades or longer. Following World War I, the issue of hyperinflation in Austria and Germany stimulated a considerable amount of original accounting research. After the inflationary period, a series of competing Bilanztheorien, discussed in the text, dominated the scene. Two figures emerged supremely from this struggle. The first was Eugen Schmalenbach, with his “dynamic accounting”, a series of further important contributions to inflation accounting, to the master chart of accounts, to cost accounting, and to other areas of business economics. The other scholar was Fritz Schmidt, with his organic accounting theory that promoted replacement values and his emphasis on the profit and loss account, no less than the balance sheet. The gamut of further eminent personalities, listed in chronological order, contains the following names: Schär, Penndorf, Leitner, Gomberg, Nicklisch, Rieger, Prion, Osbahr, Passow, Dörfel, Sganzini, Walb, Calmes, Kalveram, Meithner, Lion, Töndury, Mahlberg, le Coutre, Geldmacher, Max Lehmann, Leopold Mayer, Karl Seidel, Alfred Isaac, Mellerowicz, Seyffert, Beste, Gutenberg, Käfer, Seischab, Kosiol, Münstermann, and others. Separate Sections or Sub‐Sections are devoted to charts and master charts of accounts in German accounting theory, as well as to cost accounting and the writing of accounting history.

Die touristische Standortsbestimmung umfasst im Grunde genommen die Erscheinung Fremdenverkehr an sich. Sie projiziert diese lediglich nach örtlichen Gesichtspunkten. Dafür kann entweder die Methode der Beschreibung oder aber jene der Erklärung Platz greifen. Jene überwiegt bei den Geographen, diese bei den Wirtschaftswissenschaftern. Wirtschaftliche und geographische Betrachtungsweisen werden auch im folgenden auseinandergehalten. Beide berücksichtigen indes alle Elemente, die den Fremdenverkehr konstituieren. In Betracht fallen einmal die natrlichen und kulturellen Komponenten, die einen Fremdenverkehrsort kennzeichnen und den Bedarf darauf lenken. Eine bedeutsame Rolle kommt sodann dem Faktor Entfernung zu. Ausserdem kann aber die Standortsbestimmung auch unter dem Gesichtswinkel der Marktbildung erfolgen. Sie umfasst dann alle Bestandteile des Fremdenverkehrsmarktes und die Regeln, die fr deren Zusammenspiel in örtlicher Hinsicht massgebend sind.

The purpose of this paper is to investigate the effect of different heating approaches during thermal rounding of polymer powders on powder bulk properties such as particle size, shape and flowability, as well as on the yield of process.

This study focuses on the rounding of commercial high-density polyethylene polymer particles in two different downer reactor designs using heated walls (indirect heating) and preheated carrier gas (direct heating). Powder bulk properties of the product obtained from both designs are characterized and compared.

Particle rounding with direct heating leads to a considerable increase in process yield and a reduction in powder agglomeration compared to the design with indirect heating. This subsequently leads to higher powder flowability. In terms of shape, indirect heating yields not only particles with higher sphericity but also entails substantial agglomeration of the rounded particles.

Shape modification via thermal rounding is the decisive step for the success of a top-down process chain for selective laser sintering powders with excellent flowability, starting with polymer particles from comminution. This report provides new information on the influence of the heating mode (direct/indirect) on the performance of the rounding process and particle properties.

This paper aims to offer scholars and practitioners critical arguments on the strengths and weaknesses of the shared value concept and of the mental model of economics that lies at its heart. On the basis of these arguments, it proposes the paradigm of ethicological value-added creation as a new economic framework extending the shared value concept into a concept of lastingly viable business strategy.

Conceptual and philosophical analysis of the mental model of economics and of basic concepts and premises regarding scarcity, competition, growth and raising value. Application of this analysis to the re-design of the shared value approach and to the development of practical guidelines for sustainably viable business models.

This paper highlights how the shared value approach can be transformed into an even stronger strategic tool for the design of viable business models.

Scholars, entrepreneurs and managers receive a new conceptual framework to design lastingly viable business models on the basis of re-defined tools and concepts.

Leading texts on strategy and business development as well as CSR-driven texts on designing sustainable business models do not bridge the paradox of destructive wealth creation, i.e. the fact that individually rational and, in itself, highly successful economic behaviors lead, on the group level and the level of the whole system, to an outcome that by and large is highly destructive, as it places the social, ecological and economic sources of this wealth creation process in existential jeopardy. The paper proposes a new framework of economic reasoning for solving the paradoxes that shape current economic models and the shared value approach. It offers a first set of indicators, the parameters by which the shared value approach can be transformed into a living model for generating resource growth and added value creation cycles that stop the present downward spiral of acceleration, disruption, concentration and resource depletion. The paper thus presents forms of shared value creation that are more holistic and sustainable.