Introductory Chapter: Introduction to the Design and the Control of Electrical Machines

The division of the total core losses in the electrical steel of the magnetic circuit into two components – losses dueto hysteresis and eddy currents – is a serious technical problem, the solution of which will effectively design and construct electrical machines with magnetic circuits having low magnetic losses. In this regard, an important parameter is the exponent α, with which the frequency of magnetization reversal is included in the total losses in steel. Theoretically, this indicator can take values from 1 to 2. Most authors take α equal to 1.3, which corresponds to the special case when the eddy current losses are three times higher than the hysteresis losses. In fact, for modern electrical steels, the opposite is true. To refine the index α, an attempt was made to separate the total core losses on the basis that the hysteresis component is proportional to the first degree of the magnetization reversal frequency, and the eddy current component is proportional to the second degree. In the article, the calculation formulas of these components are obtained, containing the values of the total losses measured in idling experiments at two different frequencies, and the ratio of these frequencies. It is shown that the rational frequency ratio is within 1.2. Presented the graphs and expressions to determine the exponent α depending on the measured no-load losses and the frequency of magnetization reversal.

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Introduction: Plato’s Nightmare

10.3366/edinburgh/9781474424561.003.0001 ◽

2018 ◽

Author(s):

John Marmysz

Keyword(s):

Immanuel Kant ◽

Martin Heidegger ◽

Friedrich Nietzsche ◽

Objective Reality

This introductory chapter examines the “problem” of nihilism, beginning with its philosophical origins in the ideas of Plato, Immanuel Kant, Friedrich Nietzsche and Martin Heidegger. It is argued that film is an inherently nihilistic medium involving the evocation of illusory worlds cut loose from objective reality. This nihilism of film is distinguished from nihilism in film; the nihilistic content also present in some (but not all) movies. Criticisms of media nihilism by authors such as Thomas Hibbs and Darren Ambrose are examined. It is then argued, contrary to such critics, that cinematic nihilism is not necessarily degrading or destructive. Because the nihilism of film encourages audiences to linger in the presence of nihilism in film, cinematic nihilism potentially trains audiences to learn the positive lessons of nihilism while remaining safely detached from the sorts of dangers depicted on screen.

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Introduction: Exploring Russian nationalisms

10.3366/edinburgh/9781474433853.003.0001 ◽

2018 ◽

Author(s):

Pål Kolstø ◽

Helge Blakkisrud

Keyword(s):

The State ◽

Complex Interplay ◽

Recent Developments ◽

Part Structure

Russian societal nationalism comes in various guises, both ethnic and imperialist. Also Putin’s rhetoric is marked by the tensions between ethnic and state-focused, imperialist thinking. Noting the complex interplay of state nationalism and societal nationalism, this introductory chapter examines the mental framework within which Russian politicians were acting prior to the decision to annex Crimea. The chapter develops a typology of Russian nationalisms, surveys recent developments, and presents the three-part structure of this book: official nationalism, radical and other societal nationalisms, and identities/otherings. It concludes that after the annexation of Crimea, when the state took over the agenda of both ethnic and imperialist nationalists in Russia, societal nationalism finds itself at low ebb.

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