163,395 research outputs found
The effect of a single HOM-damper cell within a channel of undamped cells
No full textThe effect of a single HOM-damper cell within a channel of undamped cells is described theoretically using an equivalent circuit model. From this a simple equation can be derived which relates the Q-value of the single damping-cell, the bandwidth of the passband under consideration, and the additional phase shift which is introduced by the damper cell to provide energy flow into the damper cell. This equation immediately shows the limitations of such single cell damping systems. Comparisons with experimental results are shown
Picture of John W. Thomason outside home in Terrell TX
No full textPicture of John W. Thomason outside of Terrell, TX hom
On Hom-Leibniz and Hom-Lie-Yamaguti Superalgebras
No full textIn this paper some characterizations of Hom-Leibniz superalgebras are given and some of their basic properties are found. These properties can be seen as a generalization of corresponding well-known properties of Hom-Leibniz algebras. Considering the Hom-Akivis superalgebra associated to a given Hom-Leibniz superalgebra, it is observed that the Hom-super Akivis identity leads to an additional property of Hom-Leibniz superalgebras, which in turn gives a necessary and sufficient condition for Hom-super Lie admissibility of Hom-Leibniz superalgebras. We also show that every (left) Hom-Leibniz superalgebra has a natural super Hom-Lie-Yamaguti structure
John W. Thomason in the yard of his Huntsville, Tx home
No full textJohn W. Thomason in the yard of his Huntsville, Tx hom
Herbert Thomason, John W. Thomason's brother in the yard of his Huntsville, Tx home
No full textHerbert Thomason, brother of John W. Thomason in the yard of his Huntsville, Tx hom
Extensions of hom-Lie algebras in terms of cohomology
No full textsummary:We study (non-abelian) extensions of a given hom-Lie algebra and provide a geometrical interpretation of extensions, in particular, we characterize an extension of a hom-Lie algebra by another hom-Lie algebra and discuss the case where has no center. We also deal with the setting of covariant exterior derivatives, Chevalley derivative, Maurer-Cartan formula, curvature and the Bianchi identity for the possible extensions in differential geometry. Moreover, we find a cohomological obstruction to the existence of extensions of hom-Lie algebras, i.e., we show that in order to have an extendible hom-Lie algebra, there should exist a trivial member of the third cohomology
Bedeutung und Bekämpfung von Schadinsekten an Winterweizen und Winterraps in Schleswig-Holstein, 1999-2001, und der Trend der Insektizid-Behandlungen von 1999-2004
No full textIn the average of 1999 to 2004 winter wheat covered 64 % of the agricultural land of Schleswig-Holstein (331.000 ha), winter oilseed rape 31 %. These two important crops (covering 95 % of the acreage) were attacked in 1999 to 2001 by a) wheat: cereal leaf beetles (Oulema spp.Col., Chrysomelidae) and by cereal aphids (mainly Sitobion avenae and Metopolophium dirhodum; Hom., Aphididae; b) Oilseed rape: by pollen beetles (Meligethes aeneus F.; Col., Nitidulidae) and by the cabbage seed weevil Ceutorrhynchus assimlis (Payk.) (Col., Curculionidae). Studies (with six field experiments per crop, at two sites, 1999 to 2001) were done by the first author in the course of the work on a PhD thesis (Kirch 2006) to clarify the economic importance of these pests, and to look for the validity of the action thresholds published. Additionally, 51 farmers were inquired for their insecticide use, 1999 to 2004.Winterweizen bedeckte 1999-2004 64 % der Ackerfläche Schleswig-Holsteins, Winterraps 31 %. Die wichtigsten Schädlinge an Winterweizen waren die drei Getreideblattlausarten (Hom., Aphididae)(Sitobion avenae und Metopolophium dirhodum, selten Rhopalosiphum padi) und die beiden Oulema-Arten (Getreidehähnchen)(O. melanopus und O. lichenis) (Col., Chrysomelidae). An Winterraps traten im Untersuchungszeitraum auf: Meligethes aeneus (F.) (Rapsglanzkäfer) (Col., Nitidulidae) und Ceutorrhynchus assimilis (Payk.) (Kohlschotenrüßler) (Col., Curculionidae). In beiden Kulturen wurden sechs Feldversuche durchgeführt, mit frühen und späten Insektizid-Applikationen (an je zwei Standorten, mit vierfacher Wiederholung). Bei Weizen waren die Parzellen 50 m² groß, bei Raps 90 m². Bei Winterweizen zeigten beide Schaderreger-Gruppen negative Einflüsse auf den Ertrag, wenn sie nicht bei Bekämpfungsschwellen bekämpft wurden. Sowohl der Getreidehähnchen - als auch der Blattlausbefall waren signifikant negativ mit dem Ertrag korreliert. Die ökonomische Auswertung ergab, dass im Untersuchungszeitraum – bei Beachtung der Bekämpfungsschwellen - die frühe Bekämpfung der Getreidehähnchen-Larven wirtschaftlicher war als die spätere der Getreideblattläuse. Bei Winterraps erwies sich die Bekämpfung des Kohlschotenrüsslers als ertraglich und ökonomisch vorteilhaft, selbst ohne Auftreten von Dasineura brassicae (Winn.), der Kohlschotenmücke. Die Bekämpfung des Rapsglanzkäfers hingegen war nur in einem von sechs Versuchen ertragsmäßig und ökonomisch erfolgreich. Die Probleme bei diesem Schädling sind 1. die zu niedrige Bekämpfungsschwelle und 2. die Resistenz gegenüber synthetischen Pyrethroiden. Wurden in Schleswig-Holstein 1999 75.000 ha Ackerfläche mit Insektiziden behandelt (22.7 % AF), stieg die Fläche bis 2004 auf 220.000 (66.5 % AF). Die Anteile der einzelnen Wirkstoffe haben sich verändert
The design of the HOM-damping cells for the S-band linear collider
No full textDamping cells for the higher order modes are necessary for the S-band linear collider to minimize BBU (Beam-Break-Up). The construction of the damper cells has to take into account the different field geometries of the higher order modes. So two different types of dampers have been designed: a wall slotted an an iris slotted cell. In order to optimize the two types of damping cells with respect to damping strength, impedance matching between coupling system and waveguide dampers and between damping cell and undamped cells and the tuning system, damping cells of both types have been built and examinated
Prof. Th. W. Adorno and the author Hans Erich Nossack.
No full textProf. Th. W. Adorno and the author Hans Erich Nossack at a reception of Insel Verlag, Buchmesse Frankfurt 1966LB
Quality factor measurements in cavities with mode overlap
No full textA new method of measuring quality factors in cavities is presented. This method is well suited to measure quality factors in undamped cavities as well as in heavily damped cavities, and in addition this method provides a possibility of separating modes and measuring quality factors especially in cases of overlapping modes. Measurements have been carried out on HOM-damped cavities for the DESY/THD linear collider project. Results are presented
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