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Article
Publication date: 7 March 2016

Andreas 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…

231

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.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 35 no. 2
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 June 2003

Barbara F.H. Allen

Discusses collection building of contemporary German belles‐lettres and introduces 20 contemporary German‐language writers of the younger generation, presenting their…

923

Abstract

Discusses collection building of contemporary German belles‐lettres and introduces 20 contemporary German‐language writers of the younger generation, presenting their bio‐bibliographies. Librarians who are not already collecting these authors might consider expanding their German literature collections by adding some of the works listed.

Details

Collection Building, vol. 22 no. 2
Type: Research Article
ISSN: 0160-4953

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Article
Publication date: 1 March 1985

Tomas Riha

Nobody concerned with political economy can neglect the history of economic doctrines. Structural changes in the economy and society influence economic thinking and, conversely…

2717

Abstract

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.

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International Journal of Social Economics, vol. 12 no. 3/4/5
Type: Research Article
ISSN: 0306-8293

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Article
Publication date: 1 April 1993

Peter R. Senn

Investigates the importance of English language sources ofFriedrich Theodor Althoff (1839‐1908), a German of great influence bothin his own country and, indirectly, in the United…

85

Abstract

Investigates the importance of English language sources of Friedrich Theodor Althoff (1839‐1908), a German of great influence both in his own country and, indirectly, in the United States. Explores some measures of his influence in education and international understanding. Examines a wide variety of sources. Explains how it could happen that an influential person would end up in intellectual history with almost no recognition. Challenges several conventional assessments. Althoff′s most important contributions are in print and more almost certainly exist in university archives, but the material is scattered and unorganized. Because we do not yet have the full story of this remarkable and complex man, firm conclusions about his influence are not yet possible.

Details

Journal of Economic Studies, vol. 20 no. 4/5
Type: Research Article
ISSN: 0144-3585

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Book part
Publication date: 7 October 2020

Helen Thompson

Both the ideals of the European Union (EU) and the EU's recent political difficulties have attracted comparison with the Habsburg empire. In recent years, some of those making…

Abstract

Both the ideals of the European Union (EU) and the EU's recent political difficulties have attracted comparison with the Habsburg empire. In recent years, some of those making comparison have turned to the Austrian Jewish novelists, Stefan Zweig and Joseph Roth, who were crucial to the imaginative emergence of the Habsburg Myth. This paper analyses their writings and those of Robert Musil and Gregor von Rezzori in relation to the Habsburg Myth as a story about European unity, about Austria-Hungary as a supranational polity and about Austria-Hungary's self-proclaimed providential purpose in European affairs. It explores the dissonance between the Habsburg Myth and the EU's territorial composition and argues that the Habsburg Myth is, nonetheless, revealing about the EU's internal hierarchies and its geopolitical difficulties in relation to Russia.

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Article
Publication date: 1 June 2000

A. Savini

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…

1158

Abstract

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.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 19 no. 2
Type: Research Article
ISSN: 0332-1649

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Book part
Publication date: 1 September 2008

Urs Luterbacher and Carla Norrlöf

Is conflict driven by environmental scarcities or an abundance of natural resources? For quite some time, this question has generated a lively academic debate. The theoretical…

Abstract

Is conflict driven by environmental scarcities or an abundance of natural resources? For quite some time, this question has generated a lively academic debate. The theoretical literature and empirical evidence it offers are inconclusive. On the one hand, authors such as Homer-Dixon (1994) have emphasized the importance of resource scarcities in explaining conflict. On the other hand, scholars such as Collier and Hoeffler (1998) have tried to link conflict with a relative abundance of natural resources. We believe that the failure to provide a coherent explanation upon which rigorous predictions can be based is due to the neglect of institutions in understanding resource use. What we will try to highlight here is the importance of institutional settings to explain this apparent paradox.

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War, Peace and Security
Type: Book
ISBN: 978-1-84950-535-2

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Article
Publication date: 15 May 2021

Konrad Szocik and Rakhat Abylkasymova

Current covid-19 pandemic challenges health-care ethics. Ones of the most important challenges are medical resources allocation and a duty to treat, often addressed to medical…

438

Abstract

Purpose

Current covid-19 pandemic challenges health-care ethics. Ones of the most important challenges are medical resources allocation and a duty to treat, often addressed to medical personnel. This paper suggests that there are good reasons to rethink our health-care ethics for future global catastrophic risks. Current pandemic shows how challenging can be an issue of resources allocation even in a relatively small kind of catastrophic event such as covid-19 pandemic. In this paper, the authors show that any future existential bigger catastrophe may require new guidelines for the allocation of medical resources. The idea of assisted dying is considered as a hypothetical scenario.

Design/methodology/approach

This is a conceptual work based on conceptual analysis at the intersection of risk studies, health-care ethics and future studies. This study builds the argument on the assumption that the covid-19 pandemic should be treated as a sort of global catastrophic risk. Findings show that there are no such attempts in currently published peer-reviewed academic literature. This is crucial concept for the meta-analysis. This study shows why and how current pandemic can be interpreted in terms of global catastrophic risk even if, literally, covid-19 does not meet all criteria required in the risk studies to be called a global catastrophe.

Findings

We can expect an emergence of discriminatory selection policy which will require some actions taken by future patients like, for example, genetic engineering. But even then it is inevitable that there will still be a large number of survivors who require medical assistance, which they have no chance of receiving. This is why this study has considered the concept of assisted dying understood as an official protocol for health-care ethics and resources allocation policy in the case of emergency situations. Possibly more controversial idea discussed in this paper is an idea of assisted dying for those who cannot receive required medical help. Such procedure could be applied in a mass-scale during a global catastrophic event.

Research limitations/implications

Philosophers and ethicists should identify and study all possible pros and cons of this discrimination rule. As this study’s findings suggested above, a reliable point of reference is the concept of substantial human enhancement. Human enhancement as such, widely debated, should be studied in that specific context of discrimination of patients in an access to limited medical resources. Last but not least, scientific community should study the concept of assisted dying which could be applied for those survivors who have no chance of obtaining medical care. Such criteria and concepts as cost-benefit analysis, the ethics of quality of life, autonomy of patients and duty of medical personnel should be considered.

Practical implications

Politicians and policymakers should prepare protocols for global catastrophes where these discrimination criteria would have to be applied. The same applies to the development of medical robotics aimed at replacing human health-care personnel. We assume that this is important implication for practical policy in healthcare. Our prediction, however plausible, is not a good scenario for humanity. But given this realistic development trajectory, we should do everything possible to prevent the need for the discriminatory rules in medical care described above.

Originality/value

This study offers the idea of assisted dying as a health-care policy in emergency situations. The authors expect that next future global catastrophes – looking at the current pandemic only as a mild prelude – will force a radical change in moral values and medical standards. New criteria of selection and discrimination will be perceived as much more exclusivist and unfair than criteria applied today.

Details

International Journal of Human Rights in Healthcare, vol. 15 no. 4
Type: Research Article
ISSN: 2056-4902

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Article
Publication date: 1 March 1996

Lucy A. Tedd

This paper, based on the experience of running a workshop on library automation in Estonia combined with visits to several major libraries, outlines the main problems faced by…

63

Abstract

This paper, based on the experience of running a workshop on library automation in Estonia combined with visits to several major libraries, outlines the main problems faced by Estonian libraries in recent years and the steps taken to improve the situation. It provides insight, through analysis of articles published by (mostly) Estonian professionals into the problems of identifying the problems — lack of funds, lack of qualifications, organisational problems, and searching for possible solutions: networking, resource sharing, use of information technology and international co‐operation. A description of the role of the Open Society's Regional Library Programme in supporting these steps and details about some of the Estonian libraries that were visited prior to the workshop complete the picture of a varied library landscape, richer for its splendid new national library in one of the smallest states on the outskirts of the new Europe.

Details

Program, vol. 30 no. 3
Type: Research Article
ISSN: 0033-0337

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Book part
Publication date: 14 December 2016

Abstract

Details

Emotions, Decision-Making, Conflict and Cooperation
Type: Book
ISBN: 978-1-78635-032-9

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