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1 – 10 of 16Andreas Ruf, Michael Schröder, Aryanti Kusuma Putri, Roman Konrad, David Franck and Kay Hameyer
The purpose of this paper is to focus on the mechanical bearing load caused by the unbalanced magnetic pull (UMP), which is studied in detail. The applied approach is based on an…
Abstract
Purpose
The purpose of this paper is to focus on the mechanical bearing load caused by the unbalanced magnetic pull (UMP), which is studied in detail. The applied approach is based on an analysis of static and dynamic eccentricities at different positions and different amplitudes. The influence of the operating points is calculated to show the effective bearing load for machines operating at different speeds. The decreasing lifetime of the applied bearings is examined and evaluated in detail.
Design/methodology/approach
To evaluate the proposed methodology a permanent magnet synchronous machine (PMSM) with buried magnets is used. To consider effects of slotting and saturation, a finite element (FE) model is employed. The Monte Carlo method is used to determine the most likely amplitudes of the eccentricities. Calculating the UMP for all possible operating points using a control strategy for the machine and coupling this results with a drive cycle, determines the effective force acting on the bearing.
Findings
It has been shown that the position of the eccentricity has a not significant influence on the behavior of the UMP and may therefore be neglected. The amplitude of the eccentricity vector influences the amplitude of the UMP including all harmonic force components. For technical relevant eccentricities, the influence is approximately linear for the average and the dominant harmonics of the UMP. In most cases, it is sufficient to displace the rotor at an arbitrary position and amplitude. It is sufficient to simulate one type of eccentricity (static or dynamic) with an arbitrary value of displacement (rotor or stator) to evaluate all possible airgap unbalances. Using stochastic simulations of the eccentricity amplitudes enables an a priori design and lifetime estimation of bearings.
Originality/value
This paper gives a close insight on the effect of mechanical bearing load caused by rotor eccentricities. The effect of the position of the eccentricity vector, the operational range and a drive cycle are considered. A stochastic simulation and an empirical lifetime model of one bearing gives an example of using this methodological approach.
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Andreas Ruf, Simon Steentjes, David Franck and Kay Hameyer
The purpose of this paper is to focus on the frequency-dependent non-linear magnetization behaviour of the soft magnetic material, which influences both the energy loss and the…
Abstract
Purpose
The purpose of this paper is to focus on the frequency-dependent non-linear magnetization behaviour of the soft magnetic material, which influences both the energy loss and the performance of the electrical machine. The applied approach is based on measured material characteristics for various frequencies and magnetic flux densities. These are varied during the simulation according to the operational conditions of the rotating electrical machine. Therewith, the fault being committed neglecting the frequency-dependent magnetization behaviour of the magnetic material is examined in detail.
Design/methodology/approach
The influence of non-linear frequency-dependent material properties is studied by variation of the frequency-dependent magnetization characteristics. Two different non-oriented electrical steel grades having the same nominal losses at 1.5 T and 50 Hz, but different thickness, classified as M330-35A and M330-50A are studied in detail. Both have slightly different magnetization and loss behaviour.
Findings
This analysis corroborates that it is important to consider the frequency-dependency and saturation behaviour of the ferromagnetic material as well as its magnetic utilization when simulating electrical machines, i.e., its performance. The necessity to change the magnetization curve according to the applied frequency for the calculation of operating points depends on the applied material and the frequency range. Using materials, whose magnetization behaviour is marginally affected by frequency, causes a deviation in the flux-linkage and the electromagnetic torque in a small frequency range. However, analysing larger frequency ranges, the frequency behaviour of the material cannot be neglected. For instance, a poorer magnetizability requires a higher quadrature current to keep the same torque leading to increased copper losses. In addition, the applied iron-loss model plays a central role, since changes in magnetization behaviour with frequency lead to changes in the iron losses. In order to study the impact, the iron-loss model has to be capable to incorporate the harmonic content, because particularly the field harmonics are influenced by the shape of the magnetization curve.
Originality/value
This paper gives a close insight on the way the frequency-dependent non-linear magnetization behaviour affects the energy loss and the performance of electrical machines. Therewith measures to tackle this could be derived.
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Andrzej Demenko, Ivo Doležel, Kay Hameyer, Wojciech Pietrowski and Krzysztof Zawirski
Sarah Lisa Schuhbauer and Andrea Hausmann
This study aims to identify pitfalls in the use of cooperation for the implementation of digital applications in rural cultural tourism marketing and derive practical implications…
Abstract
Purpose
This study aims to identify pitfalls in the use of cooperation for the implementation of digital applications in rural cultural tourism marketing and derive practical implications for avoiding them.
Design/methodology/approach
A total of 14 semi-structured in-depth interviews were conducted with the participants of the cooperation project around the Web app “The Legend of the Call of the Mountain” in the Zugspitz Region in Germany.
Findings
The study has identified four key pitfalls: challenges in the long-term financing, destination-specific characteristics of rural areas, doubts about the use of evaluations and the limited horizon of many cultural institutions.
Research limitations/implications
Because of the qualitative approach and the single case study, the results may lack generalisability. Therefore, future research should place the results to a larger scale, for example, with a mixed methods approach.
Practical implications
Practical implications can be derived from the study for avoiding pitfalls and thus for a successful use of such cooperation projects. The implications draw attention to the different possibilities of long-term financing, the important role of a central tourism organisation, the special possibilities of evaluations and the important role of general awareness raising for the added values of such cooperation.
Originality/value
By examining an exemplary cooperation project, the paper fills an existing research gap, as there has been little knowledge in empirical cultural tourism research about the special conditions for using cooperation to implement digital applications in rural cultural tourism marketing.
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Tereza Hájková and Andrea Kalendova
– This paper aims to synthesise anticorrosion pigments containing molybdenum for paints intended for corrosion protection of metals.
Abstract
Purpose
This paper aims to synthesise anticorrosion pigments containing molybdenum for paints intended for corrosion protection of metals.
Design/methodology/approach
The anticorrosion pigments were prepared by high-temperature solid-state synthesis from the appropriate oxides, carbonates and calcium metasilicate. Stoichiometric molybdates and core-shell molybdates with a non-isometric particle shape containing Ca, Sr, Zn, Mg and Fe were synthesised. The pigments were examined by X-ray diffraction analysis and scanning electron microscopy. Paints based on an epoxy resin and containing the substances at a pigment volume concentration of 10 volume per cent were prepared. The paints were subjected to physico-mechanical tests and to tests in corrosion atmospheres. The corrosion test results were compared to those of the paint with a commercial pigment, which is used in many industrial applications.
Findings
The molybdate structure of each pigment prepared was elucidated. The core-shell molybdates exhibit a non-isometric particle shape. The pigments prepared were found to impart a very good anticorrosion efficiency to the paints. A high anticorrosion efficiency was found with the pigments Fe2(MoO4)3 and Fe2(MoO4)3/CaSiO3 and with Mg and Zn molybdates.
Practical implications
The pigments can be used for the formulation of paints intended for the corrosion protection of metals. The pigments also improve the paints’ physical properties.
Originality/value
The use of the pigments in anticorrosion paints for the protection of metals is new. The benefits include the use and the procedure of synthesis of the anticorrosion pigments which are free from heavy metals and are acceptable from the aspect of environmental protection. Moreover, the core-shell molybdates, whose high efficiency is comparable to that of the stoichiometric molybdates, have lower molybdenum contents.
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Andrea Friedrich, Rüdiger Kabst, Wolfgang Weber and Maria Rodehuth
This article raises the question of to what extent functional flexibility is an operatively designed approach with which European companies confront current short‐term changes in…
Abstract
This article raises the question of to what extent functional flexibility is an operatively designed approach with which European companies confront current short‐term changes in their environment, and whether functional flexibility is integrated into long‐term human resource strategies. The proposition is tested that organisations with a strategic human resource management in the sense of a coordinated, objective‐oriented personnel management pattern, show a higher probability of using job rotation than organisations lacking a strategic‐oriented human resource management approach.
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Alexandra L. Ferrentino, Meghan L. Maliga, Richard A. Bernardi and Susan M. Bosco
This research provides accounting-ethics authors and administrators with a benchmark for accounting-ethics research. While Bernardi and Bean (2010) considered publications in…
Abstract
This research provides accounting-ethics authors and administrators with a benchmark for accounting-ethics research. While Bernardi and Bean (2010) considered publications in business-ethics and accounting’s top-40 journals this study considers research in eight accounting-ethics and public-interest journals, as well as, 34 business-ethics journals. We analyzed the contents of our 42 journals for the 25-year period between 1991 through 2015. This research documents the continued growth (Bernardi & Bean, 2007) of accounting-ethics research in both accounting-ethics and business-ethics journals. We provide data on the top-10 ethics authors in each doctoral year group, the top-50 ethics authors over the most recent 10, 20, and 25 years, and a distribution among ethics scholars for these periods. For the 25-year timeframe, our data indicate that only 665 (274) of the 5,125 accounting PhDs/DBAs (13.0% and 5.4% respectively) in Canada and the United States had authored or co-authored one (more than one) ethics article.
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Valentina Cucino, Cristina Marullo, Eleonora Annunziata and Andrea Piccaluga
Humane Entrepreneurship (HumEnt) is strongly purpose-oriented and characterized by a focus on inclusiveness and social and environmental sustainability, with attention to both…
Abstract
Purpose
Humane Entrepreneurship (HumEnt) is strongly purpose-oriented and characterized by a focus on inclusiveness and social and environmental sustainability, with attention to both internal and external stakeholders and their needs. In the attempt to provide new research in this field, this study aims to conduct an empirical investigation within the theory of HumEnt and, in particular, of the Human Resource Orientation (HRO) model among Italian Small and Medium-size Enterprises.
Design/methodology/approach
Based on quantitative data, this study used a deductive approach to investigate the relationship between the HumEnt model and firms’ relational embeddedness with different types of stakeholders (value chain stakeholders and societal stakeholders, respectively). More concretely, to investigate the relationships between the dimensions of the HumEnt model and firms’ relational embeddedness, partial least squares structural equation modeling was applied.
Findings
Findings of this study suggest that Entrepreneurial Orientation (EO) directly contributes only to value chain embeddedness. However, the results also show that if EO is mediated by an HRO (i.e. companies with a high HRO), a high level of societal embeddedness is also present.
Originality/value
This study represents a first attempt to provide comprehensive empirical evidence about the different dimensions characterizing the HumEnt theoretical model, and to highlight their relevance in supporting companies’ relational embeddedness capacity with different categories of stakeholders.
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Petr Mošner, Andrea Kalendová, Ladislav Koudelka and Petr Kalenda
Four pigments derived from the SrO–ZnO–B2O3–P2O5 system were tested in a solvent coating system based on a modified alkyd resin and water‐borne system based on a styrene–acrylate…
Abstract
Four pigments derived from the SrO–ZnO–B2O3–P2O5 system were tested in a solvent coating system based on a modified alkyd resin and water‐borne system based on a styrene–acrylate dispersion. The pigments pastes were applied on activated steel panels and after conditioning standard corrosion tests were performed comprising the determination of resistance to humid atmospheres containing SO2 and also the resistance to a neutral salt fog. Test results were compared with those performed on the coatings prepared with standard anticorrosion pigments of Zn3(PO4)2.2H2O, Ca(BO2)2, Zn(BO2)2 a Ba(BO2)2. Some tested pigments revealed at least comparable corrosion‐inhibition properties with standard pigments. Coatings based on alkyd resins gave better results than those prepared form water‐borne system.
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The purpose of this paper is to focus on the comparative analysis of the Balanced Scorecards of four higher education institutions and aims to define the general framework of the…
Abstract
Purpose
The purpose of this paper is to focus on the comparative analysis of the Balanced Scorecards of four higher education institutions and aims to define the general framework of the Balanced Scorecard for the higher education institution which concerns: the structure and elements of the Balanced Scorecard; development of the Balanced Scorecards on the different levels of the management system of the higher education institution; definition of the main functions of the Balanced Scorecard which it performs in the process of the strategic management of the German higher education institutions. Balanced Scorecard is analyzed as a strategic management system that translates a higher education institution’s strategy into a comprehensive set of performance measures that provides a framework for a strategic measurement and management system.
Design/methodology/approach
The comparative content analysis of the Balanced Scorecards of one Austrian and three German higher education institutions – Johanes Gutenberg University Mainz, Münster University of Applied Sciences (Fachhochschule Münster), Cologne University of Applied Sciences (Fachhochschule Köln), Montan University Leoben.
Findings
Using a comparative analysis of the Balanced Scorecards of four higher education institutions this paper argues that Balanced Scorecard provides a systemic view of the strategy of a higher education institution. It ensures a full complex framework for implementation and controlling of the strategy and sets a basis for further learning in the process of the strategic management of the higher education institution according to the scheme “plan-do-check-act”.
Research limitations/implications
This paper provides a basis for the substantial further work on the development of the general framework of the Balanced Scorecard for the higher education institution.
Practical implications
The framework presented in this paper can be used as the basis for the development of general framework of the Balanced Scorecard of the higher education institution.
Social implications
The framework presented in this paper can be used as the basis for the development of general framework of the Balanced Scorecard of the higher education institution.
Originality/value
This paper indicates the particularities of the structure and elements of the Balanced Scorecard, its development in the different levels of the management system of the higher education institution.
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