Notes on planar semimodular lattices. I. Construction

We construct all planar semimodular lattices in three simple steps from the direct product of two chains.Comment: 13 pages with 9 diagram

The Hedonic Price Structure of Faculty Compensation at U.S. Colleges and Universities

Economic theory suggests that the variation in academic salaries across institutions in part reflects compensating differences associated with variation in the levels of local quality of life factors such as environmental quality and the provision of local public services. This paper presents an econometric analysis of the hedonic, or implicit price structure, of faculty compensation at U.S. colleges and universities using data from AAUP merged with data on a host of location-specific characteristics. Quality of life factors are found to be important, accounting for between 7 percent and 12.8 percent of total compensation

Active clearance control system for a turbomachine

An axial compressor is provided with a cooling air manifold surrounding a portion of the shroud, and means for bleeding air from the compressor to the manifold for selectively flowing it in a modulating manner axially along the outer side of the stator/shroud to cool and shrink it during steady state operating conditions so as to obtain minimum shroud/rotor clearance conditions. Provision is also made to selectively divert the flow of cooling air from the manifold during transient periods of operation so as to alter the thermal growth or shrink rate of the stator/shroud and result in adequate clearance with the compressor rotor

GLSM realizations of maps and intersections of Grassmannians and Pfaffians

In this paper we give gauged linear sigma model (GLSM) realizations of a number of geometries not previously presented in GLSMs. We begin by describing GLSM realizations of maps including Veronese and Segre embeddings, which can be applied to give GLSMs explicitly describing constructions such as the intersection of one hypersurface with the image under some map of another. We also discuss GLSMs for intersections of Grassmannians and Pfaffians with one another, and with their images under various maps, which sometimes form exotic constructions of Calabi-Yaus, as well as GLSMs for other exotic Calabi-Yau constructions of Kanazawa. Much of this paper focuses on a specific set of examples of GLSMs for intersections of Grassmannians G(2,N) with themselves after a linear rotation, including the Calabi-Yau case N=5. One phase of the GLSM realizes an intersection of two Grassmannians, the other phase realizes an intersection of two Pfaffians. The GLSM has two nonabelian factors in its gauge group, and we consider dualities in those factors. In both the original GLSM and a double-dual, one geometric phase is realized perturbatively (as the critical locus of a superpotential), and the other via quantum effects. Dualizing on a single gauge group factor yields a model in which each geometry is realized through a simultaneous combination of perturbative and quantum effects.Comment: LaTeX, 50 pages; v2: typos fixed and a few comments on other dualities adde

The classification of LANDSAT data for the Orlando, Florida, urban fringe area

Procedures used to map residential land cover on the Orlando, Florida, Urban fringe zone are detailed. The NASA Bureau of the Census Applications Systems Verification and Transfer project and the test site are described as well as the LANDSAT data used as the land cover information sources. Both single-date LANDSAT data processing and multitemporal principal components LANDSAT data processing are described. A summary of significant findings is included

Strahlenpharmakologische untersuchungen mit neutronen an eisenhaltigen praparaten im Siemens unterrichtsreaktor SUR 100

Die stark eisenhaltigen Praparate Ferrlecit, Kobaltjerrlecit, Ferrojolsan, Ferrojolcamma und Irradian wurden im Siemens Unterrichtsreaktor SUR 100 des Instituts fur Kernenergetikder Universitat Struttgart und der Technischen Universitat, Berlin mit einem NeutronenfluB von ca. 5.l06n/cm2 sec bestrahlt. Es ollte dabei untersucht werden, wie stark eisenhaltige Praparate mit diesem Reaktor aktiviert werden konnen. Es wird festgestellt, daB Eisen praktisch kaum aktiviert wird. Die Ergebnisse zeigen, daB nur das Kobattjerrlecit und das Irradian starker durch Neutrosen aktiviert werden. Die hohere Aktivitat des Kobaltjerrlecit wird auf die darin enthaltenen Elemente Mangan, Kupfer und Kobalt zuruckgefuhrt, die mit thermischen Neutronen gut aktivierbar sind. Die hohere Aktivitat des Irradian geht hauptsachlich auf &#946;-Zerfalle zuruck. Das Phosphorisotop P-32 tragt einen gro&#946;en Anteil dazu bei. De r&#946;-Untergrund des Irradian bei hohen Energien, der mit einer kleinen Halbwertszeitabklingt, ist durch keines der angefuhrten Elemente im Irradian erklarbar. Der Mn-56Peak im Spektrum ist gut erkennbar, durch den &#946;-Untergrund wird er aber zu einer hoheren Energie hin verschoben.</p

Leading for Learning: Reflective Tools for School and District Leaders

Provides reflective ideas and tools for educators to enhance leadership in learning. Includes key ideas, real examples, and reflective questions that leaders can use can use to assess their organizations, enact strategic plans, and teach colleagues

Extended Poincar\'e supersymmetry in three dimensions and supersymmetric anyons

We classify the unitary representations of the extended Poincar\'e supergroups in three dimensions. Irreducible unitary representations of any spin can appear, which correspond to supersymmetric anyons. Our results also show that all irreducible unitary representations necessarily have physical momenta. This is in sharp contrast to the ordinary Poincar\'e group in three dimensions, that admits in addition irreducible unitary representations with non-physical momenta, which are discarded on physical grounds.Comment: 7 pages; commentaries added in Sect. IV A and in Conclusion; added reference