2,368 research outputs found
Untersuchungen zum didaktischen Ort der Booleschen Algebra im Rahmen einer modernen elementaren Algebra
No full textWinkelmann B. Untersuchungen zum didaktischen Ort der Booleschen Algebra im Rahmen einer modernen elementaren Algebra. Bielefeld; 1974
Money Illusion Under Test
No full textMuch progress has been made in recent years in developing and applying a direct measure of utility using survey questions on satisfaction with income and with life in general. In this paper we apply this new type of measurement to the study of money illusion. Using data from the German Socio-Economic Panel for the years 1993 to 2003, we cannot reject the hypothesis of no money illusion.North-South, cost-of-living, subjective well-being, fixed effects
Zullobalanus santamariaensis Buckeridge & Winkelmann, sp. nov.
No full text<i>Zullobalanus santamariaensis</i> Buckeridge & Winkelmann sp. nov. <p>(Figures 2–3)</p> <p> <b>Diagnosis.</b> <i>Zullobalanus</i> with shell lacking external apico-basal ribbing; tergum only weakly reflexed apically, but possessing extensive, well-formed crests for depressor muscle attachment; scutum with moderately produced articular ridge and moderate to weak adductor muscle scar.</p> <p> <b>Distribution and age.</b> Azores; Late Miocene – Early Pliocene.</p> <p> <b>Type material.</b> Holotype containing 2 sample compositions: DBUA-F 536.1, complete shell (3.23 mm in height and 3.39 mm in basal diameter), carina (5.44 mm in height), carinolatus, (5.36 mm in height), latus (1.84 mm in height), rostrum (2.59 mm in height), scutum (2.50 mm in articular margin), tergum (3.44 mm in articular margin); DBUA-F 536.2, complete shell (6.31 mm in height and 6.63 mm in basal diameter), carina (4.89 mm in height), carinolatus, (4.79 mm in height), latus (3.36 mm in height), rostrum (2.30 mm in height), scutum (2.43 mm in articular margin), tergum (3.61 mm in articular margin); Santa Maria, Malbusca outcrop (25°4'7.04"W, 36°55'45.53"N [30 m asl]); S.P. Ávila & K. Winkelmann, 22–29 June 2008. Paratypes all with same locality, collectors and date as the holotype: Natural History Museum Berlin: MB.A 1733, MB.A 1734; Natural History Museum Vienna: NHMW 2010/0088/0001, NHMW 2010/0088/0002; Royal Belgian Institute of Natural Sciences Brussels: IRSNB 7255a–g, IRSNB 7256a–g; Natural History Museum London: NHM IC 549 – NHM IC 562; Muséum National d’Histoire Naturelle Paris: MNHN A32053, MNHN A32054.</p> <p> <b>Description.</b> Shell conic, height approximating basal diameter; exterior rough, longitudinal ribbing weak to absent, lateral growth lines weak; orifice rhomboidal (Fig. 2 A, B); interior with strong ribbing, with minor bifurcation of some ribs near basis; rib cross-section showing simple arborescent interlaminate structures (Fig. 2 B, C); sheath smooth, well developed, pendant, occupying up to 50% of height of inner surface; basis firmly interlocking with parietal ribs; radii moderately narrow, with oblique summits, growth lines parallel to basis crossed by fine growth striae parallel to alar abutment (Fig. 2 B); alae with marginal extensions, summits almost horizontal (Fig. 2 B).</p> <p>Scutum (Fig. 3 A, B) very weakly reflexed apically; exterior with strong transverse growth ribs crossed by weak apico-basal striae; interior with articular ridge moderately produced, slightly pendant basally; adductor ridge weak, broadly rounded; adductor muscle scar moderate to weak, pit for lateral depressor muscles well formed lacking any obvious muscle attachment crests. Tergum (Fig. 3 C, D) moderately elongate, spur wellformed, removed from basi-scutal angle by own width and extending beyond same angle by approximately its own width, furrow well-formed distally, externally with well spaced growth lines, in some areas (especially basally), fine apico-basal striae present; interior with longitudinal furrow on articular margin wide, open, shallow, smooth except for weak growth striae; articular ridge well-formed, concave towards articular margin; crests for depressor muscles well developed basally, extending as a zone of raised papillae nearer the apex; articular ridge gently curved to extend slightly beyond a broadly concave basal margin; apex with approximately 3–4 strong transverse growth lines in adults.</p> <p> <b>Occurence at Santa Maria Island.</b> All the Late-Miocene and Early-Pliocene outcrops studied in Santa Maria contained the endemic barnacle <i>Zullobalanus santamariaensis</i> <b>sp. nov.</b> Most specimens were found at Malbusca and at “Pedra-que-Pica” outcrops. The beds at “Pedra-que-Pica” contained some well preserved but rare barnacles with opercula cemented to diverse marine molluscs (e.g. <i>Gigantopecten latissimus</i> (Brocchi, 1814) and <i>Lopha plicatuloides</i> (Mayer, 1864)); the beds at Malbusca contained a number of loose opercula in a sandy matrix. At Cré outcrop, rare single walls as well as opercula were present. In the more lithified marine sediments of Figueiral and Ponta do Castelo, barnacle fragments were only observed on eroded surfaces. At Ponta dos Frades, a few barnacle fragments were found together with well preserved micro-molluscs on eroded bottom surfaces. Nevertheless, we detected fragments of <i>Zullobalanus santamariaensis</i> <b>sp. nov.</b> in every sampled Miocene/Pliocene outcrop.</p> <p> <b>Remarks and affinities.</b> There is an extensive archaeobalanid fauna known from western Europe (Carriol, 2008) and the eastern seaboard of North America (Zullo 1984; Zullo & Kite 1985; Zullo & Perreault 1989; Zullo & Portell 1991). Of these, species of <i>Actinobalanus</i> are distinguished from this taxon by their porous bases; <i>Hesperibalanus</i>, the terga of which lack the well-formed nodose papillae on the internal surface and the broad spur; <i>Solidobalanus</i> by the externally smooth compartments; and <i>Lophobalanus</i> by their very narrow radii.</p> <p> <i>Zullobalanus santamariaensis</i> <b>sp. nov.</b> differs from all other <i>Zullobalanus</i> species by a lack of clearly formed external ribbing on the shell. Although there are some weak “ribs” these are somewhat obscured by the generally rough surface of the shell. The weakly reflexed scutal apex is close to that seen in the Australian species <i>Zullobalanus australiae victoriae</i> (Buckeridge, 1983) and in most respects it is closest to this species. In addition to the lack of external ribbing, it differs from <i>Z. australiae victoriae</i> by the presence of numerous well-formed crests for depressor muscles on the tergum.</p> <p> The scutal articular ridge is often basally pendant in larger specimens of <i>Zullobalanus</i> species (Buckeridge 1983), and although this has not been clearly seen in the material available, we should be mindful that all larger scuta are isolated and since shell disarticulation, have been abraded, as such wearing away delicate extensions.</p> <p> <b>Etymology.</b> Geographic: Island of Santa Maria (noun in apposition).</p>Published as part of <i>Winkelmann, Kai, Buckeridge, John S., Costa, Ana Cristina, Dionísio, Maria Ana Manso, Medeiros, André, Cachão, Mário & Ávila, Sérgio P., 2010, Zullobalanus santamariaensis sp. nov., a new late Miocene barnacle species of the family Archaeobalanidae (Cirripedia: Thoracica), from the Azores, pp. 33-44 in Zootaxa 2680</i> on pages 36-39, DOI: <a href="http://zenodo.org/record/199324">10.5281/zenodo.199324</a>
EBSD Kikuchi Pattern Analysis, Silicon 15kV
No full textSupplementary Data and Images for Si EBSD pattern analysis as presented in
A. Winkelmann, T.B. Britton, G. Nolze "Constraints on the effective electron energy spectrum in backscatter Kikuchi diffraction", Physical Review B (2019
On a quaternionic Picard theorem
No full textThe classical theorem of Picard states that a non-constant holomorphic
function can avoid at most one value.
We investigate how many values a
non-constant slice regular function of a quaternionic variable
may avoid
Veränderungen von Schülervorstellungen durch Experimentieren
No full textIm Rahmen des Forschungsprojekts „Fachwissenszuwachs durch Schüler- und Demonstrationsexperimentein der geometrischen Optik“ (Winkelmann & Erb, 2014) wurde im Winter 2013/14 an 22 hessischenSchulklassen unter anderem der Lernzuwachs nach einer Intervention erhoben.Die Unterrichtseinheit wurde auf drei verschiedene Arten durchgeführt, wobei der Grad der Schüleraktivitätvariiert wurde: 1. Die Schülerinnen und Schüler erhielten eine detaillierte Experimentieranleitung(„Kochbuch“), 2. die Schülerinnen und Schüler erhielten einen Arbeitsauftrag zum Experimentieren(„Guided“), 3. die Lehrkraft führte die Experimente vor („Demo“). Das Ziel einer im Rahmen einer WissenschaftlichenHausarbeit zum Ersten Staatsexamen durchgeführten Fragebogenerhebung war es, herauszu finden, welche Auswirkung die Art des Experimentierens auf die Schülervorstellungen hat. In diesemArtikel werden die Ergebnisse der Erhebung vorgestellt. Hierzu wird der Fokus auf den Zusammenhangzwischen Antwort und der Begründung der Schülerinnen und Schüler gelegt. Zusätzlich wird die Einschätzungder Schülerinnen und Schüler darüber, wie sicher sie sich bei der Beantwortung der Fragen waren,diskutiert
Lernzuwachs durch Schüler- und Demonstrationsexperimente
No full textAllgemein wird angenommen, dass das selbstständige Experimentieren durch Schülerinnen und Schüler in großem Maße zum Erfolg von Physikunterricht beitragen kann. Diese Einschätzung findet sich nicht allein in Überzeugungen von Schülerinnen und Schülern selbst (Behrendt 1990; Winkelmann & Erb 2011). Auch Lehrkräfte verbinden mit dem Einsatz von Schülerexperimenten die Hoffnung, eine Vielzahl ihrer Unterrichtsziele im Physikunterricht erreichen zu können (Welzel et al. 1998).Der vorliegende Artikel beschreibt zunächst das Studiendesign eines Forschungsprojektes, das unter anderem der Frage nachgeht, welchen Einfluss die Schüleraktivität während des Experimentierens auf den Lernzuwachs von Schülerinnen und Schülern hat. Hierfür wird zwischen der Methode des Schülerexperiments und des (Lehrer-) Demonstrationsexperiments unterschieden. Ein weiterer Abschnitt stellt Ergebnisse einer umfangreichen Erhebung aus dem Schuljahr 2012/13 an hessischen Gymnasien vor. Abschließend wird ein Ausblick über den weiteren Verlauf der Studie gegeben
Asymmetric Vertical Integration
No full textWe examine vertical backward integration in a reducedform model of successive oligopolies. Our key findings are: (i) There may be asymmetric equilibria where some firms integrate and others remain separated, even if firms are symmetric initially; (ii) Efficient firms are more likely to integrate vertically. As a result, integrated firms also tend to have a large market share. The driving force behind these findings are demand/mark-up complementarities in the product market. We also identify countervailing forces resulting from strong vertical foreclosure, upstream sales and endogenous acquisition costs.successive oligopolies, vertical integration, effciency, foreclosure
Architektonische und skulpturale Bildungsprozesse im Kunstunterricht
No full textHenning S. Architektonische und skulpturale Bildungsprozesse im Kunstunterricht. In: Budde C, Shatry B, Wagner I, Winkelmann A, eds. Architektur ganztags. Spielräume für baukulturelle Bildung. München: kopaed; 2014: 106-110
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