11,440 research outputs found
Captains' training at Swissair
The objectives, crucial points, and problems of the individual phase of the captain's basic training are examined. The prerequisites to pilot selection are given as well as a generalized outline of pilot career progression
The Szeg\"o metric associated to Hardy spaces of Clifford algebra valued functions and some geometric properties
In analogy to complex function theory we introduce a Szeg\"o metric in the
context of hypercomplex function theory dealing with functions that take values
in a Clifford algebra. In particular, we are dealing with Clifford algebra
valued functions that are annihilated by the Euclidean Dirac operator in
. These are often called monogenic functions. As a
consequence of the isometry between two Hardy spaces of monogenic functions on
domains that are related to each other by a conformal map, the generalized
Szeg\"o metric turns out to have a pseudo-invariance under M\"obius
transformations. This property is crucially applied to show that the curvature
of this metric is always negative on bounded domains. Furthermore, it allows us
to establish that this metric is complete on bounded domains.Comment: 21 page
Trace Analysis on Capillary Columns. Selected Practical Applications: Insecticides in Raw Butter Extract; Aroma Head Space from Liquors; Auto Exhaust Gas
Trace analysis on capillary columns becomes feasible provided appropriate injection techniques without stream splitting are used. To demonstrate potentialities and limitations of the methods, we investigated practical applications, the conditions of which were as dissimilar as possible. Insecticides in dairy products can be estimated by direct analysis of the raw petrol ether extract, without previous purification by column chromatography. 2-4 µl of extract are injected without splitting on a short inlet capillary fitted in a separate injection bloc. The inlet capillary is then connected to the capillary column mounted in the column oven with electron capture detector. Analysis is started by rapid heating to a constant temperature or by temperature programming resp. Head space analysis is another case in which trace components are important. Whereas several workers reported trapping of head space vapors in capillaries at low temperatures, we emphasize avoiding candensation, e.g. of water vapor, in the capillary. All sampling is done, therefore, near the original temperature of the head space material, i.e. at room temperature. In the case of coqnac aroma analysis in which most of the water and ethanol vapor are vented through the inlet capillary, the influences of most sampling variables—gas volume, length of inlet capillary—are studied. In the analysis of auto exhaust gas, again, bypassing of water is an important detail. In addition to hydrocarbons originating directly from the fuel as investigated by several authors, we found many combustion and conversion products, primarily naphthaline derivatives and phenol
Separation Efficiency Versus Column Length. An Experimental Study With Capillary Columns
The columns of different length used for studying the relation between HETP and column length are supposed to exhibit identical characteristics per meter. In the laboratory this condition cannot be rigorously fulfilled. The best approximation probably consists in starting the work with a relatively long capillary column followed by running shorter parts obtained by progressive cutting of the original column. Based on this procedure a marked increase of HETP with increasing column length is observe
Splitless Injection on Capillary Columns, Part II. Conditions and Limits, Practical Realization
Our procedure of direct splitless injection on capillary columns is based on the choice of column temperature for injection. Under appropriate conditions a marked concentration effect is observed, i.e. the eluted band is more concentrated than the injected one. The dependence of this effect on column temperature, injection time, sample size, and other variables has been studied experimentally. A solvent bypassing technique has been developed which allows the performance of trace analysis on capillary column
Splitless Injection on Capillary Columns, Part I. The Basic Technique; Steroid Analysis as an Example
A very simple procedure for splitless injection on capillary columns is discussed. In contrast to more sophisticated devices recently developed for the same purpose, the method described requires no additional equipment. The advantages of the method which broadens the use of capillary columns are discussed. Steroid analysis serves as an example of the application
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Pension fund finance and sponsoring companies: Empirical evidence on theoretical hypotheses
This study presents empirical evidence on the influence of sponsoring companies on the
funding and portfolio allocation of pension funds, an issue on which most extant literature is theoretical. We use a unique microdataset of 550 Dutch defined benefit company pension funds and 100 sponsoring firms over 1996-2005 to test the relevance of the main theoretical hypotheses, the first paper to do so in a comprehensive manner. We find that pension funds
have lower cover ratios when (1) their sponsoring company is highly leveraged, (2) the fund’s return on assets is relatively low, and (3) the sponsoring firm is small. Further, defined benefit pension funds are found to invest more in shares when their sponsoring companies are highly leveraged. These links in general suggest higher risk in the sponsor leads to correspondingly higher risk in the fund, and warrant close attention by regulators
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