Frequency response measurement in closed loop:brushing up our knowledge

Abstract Determination of the frequency response function of a system, using cross-and powerspectrum is a commonly used technique. In the closed loop situation, usually the sensitivity will be measured. The reason for doing this is sometimes a bit slipped away. Therefore this report will brush up our knowledge and consider the theoretical background. First, a theoretical examination of the open loop case is done. Correlations are determined from the time-domain formulas. Using the fourier transform, they will be converted to spectra. The frequency response function can be determined in this way. This is also done by using the frequency domain approach from the start. The frequency domain approach is also used for the determination of the closed loop system. For the closed loop system, a number of methods to determine the system are found. These methods all have their own specific properties and are useful in different conditions. The theoretical methods are tested in practice. The found properties are checked and other phenomena are examined

Amsterdamse Emigranten: Onbekende Brieven Uit de Prairie van Iowa, 1846-1873 (Book Review)

Reviewed Title: Amsterdamse Emigranten, Onbekende Brieven Uit de Prairie van Iowa (1846-1873), by Dr. J. Stellingwerff, Buyten en Schipperheyn, Amsterdam, The Netherlands, 1975, 395 pages

On the Dutch expletive and related syntactic problems

In his Über das niederländische Adverbialpronomen \u27er\u27 Bech argues that the subject expletive of Dutch is inserted when the NP subject has an indefinite article. Bech also claims that the subjective expletive is a local subject and not a logical subject. This thesis proposes that the use of the subject expletive cannot be based upon a traditional structuralist concept. The author rejects some of Bech\u27s claims and argues for a semantic distinction between definiteness and non-definiteness as a basis for expletive insertion. An attempt is also made to apply the same distinction in accounting for the use of het with object complements. Working within the framework called Relational Grammar, the author shows that each of the expletives has true grammatical relations of subject, direct object, or location to a verb. Finally, constraints on combinations of er\u27s in one sentence are shown to be controlled by a hierarchical principle

Perspectives on the Christian Reformed Church: Studies in its History, Theology, and Ecumenicity (Book Review)

Reviewed Title: Perspectives on the Christian Reformed Church: Studies in its History, Theology, and Ecumenicity, by Peter De Klerk and Richard R. De Ridder, Editors, Grand Rapids, Michigan, Baker Book House, 1983