Growth and business cycles

We present a class of convex endogenous growth models and analyze their performance in terms of both growth and business cycle criteria. The models we study have close analogs in the real business cycle literature. We interpret the exogenous growth rate of productivity as an endogenous growth rate of human capital. This perspective allows us to compare the strengths of the two classes of models. ; To highlight the mechanism that gives endogenous growth models the ability to improve upon their exogenous growth relatives, we study models that are symmetric in terms of human and physical capital formation—our two engines of growth. More precisely, we analyze models in which the technology used to produce human capital is identical to the technologies used to produce consumption and investment goods and in which the technology shocks in the two sectors are perfectly correlated.Business cycles ; Technological innovations ; Human capital

Full-Potential Modeling of Blade-Vortex Interactions

A study of the full-potential modeling of a blade-vortex interaction was made. A primary goal of this study was to investigate the effectiveness of the various methods of modeling the vortex. The model problem restricts the interaction to that of an infinite wing with an infinite line vortex moving parallel to its leading edge. This problem provides a convenient testing ground for the various methods of modeling the vortex while retaining the essential physics of the full three-dimensional interaction. A full-potential algorithm specifically tailored to solve the blade-vortex interaction (BVI) was developed to solve this problem. The basic algorithm was modified to include the effect of a vortex passing near the airfoil. Four different methods of modeling the vortex were used: (1) the angle-of-attack method, (2) the lifting-surface method, (3) the branch-cut method, and (4) the split-potential method. A side-by-side comparison of the four models was conducted. These comparisons included comparing generated velocity fields, a subcritical interaction, and a critical interaction. The subcritical and critical interactions are compared with experimentally generated results. The split-potential model was used to make a survey of some of the more critical parameters which affect the BVI

An incremental strategy for calculating consistent discrete CFD sensitivity derivatives

In this preliminary study involving advanced computational fluid dynamic (CFD) codes, an incremental formulation, also known as the 'delta' or 'correction' form, is presented for solving the very large sparse systems of linear equations which are associated with aerodynamic sensitivity analysis. For typical problems in 2D, a direct solution method can be applied to these linear equations which are associated with aerodynamic sensitivity analysis. For typical problems in 2D, a direct solution method can be applied to these linear equations in either the standard or the incremental form, in which case the two are equivalent. Iterative methods appear to be needed for future 3D applications; however, because direct solver methods require much more computer memory than is currently available. Iterative methods for solving these equations in the standard form result in certain difficulties, such as ill-conditioning of the coefficient matrix, which can be overcome when these equations are cast in the incremental form; these and other benefits are discussed. The methodology is successfully implemented and tested in 2D using an upwind, cell-centered, finite volume formulation applied to the thin-layer Navier-Stokes equations. Results are presented for two laminar sample problems: (1) transonic flow through a double-throat nozzle; and (2) flow over an isolated airfoil

Abundance: a new high-yielding storage-type hybrid onion

On Dec. 1, 1953, the Iowa and Idaho agricultural experiment stations and the United States Department of Agriculture, cooperating, announced the release of the F1 hybrid onion, Abundance, pedigree B 2108 x B 2215 . This is a long-day exceptionally high-yielding storage-type hybrid. The bulb is a high globe, light yellow in color. Abundance should find acceptance as a yellow globe type for limited storage where Early Yellow Globe is adapted.https://lib.dr.iastate.edu/specialreports/1001/thumbnail.jp

Diplomatic Metonymy and Antithesis in 3 Henry VI

This essay takes as its starting point the resemblance between the historical practice of diplomatic representation and the rhetorical practice of metonymy. The early modern ambassador acted as a substitute abroad for the sovereign who sent him and metonymy describes a comparable replacement – in words – of one thing by another associated thing. Yet metonyms can all too easily become confused with their referents or even come to replace them, as the sign is taken too literally for its signified, creating a kind of rivalry between representative and represented, as competing sources of authority, in a shift from relations of likeness to opposition. As 3 Henry VI points out – and as this essay argues – the metonymic characteristics of early modern ambassadorial representation made it vulnerable to this drift towards antithesis. Antithesis, the figure of opposition, governs the contentious disorder of 3 Henry VI, from the rhetorical patterning of its speeches to its structure and subject matter and politics. The Earl of Warwick’s embassy in Act 3 is no exception: it is the pivotal point around which the play’s oppositions turn. As Warwick moves from representing to replacing Edward IV, the figures that express his migration from substitution to subversion reflect on a comparable instability in European diplomatic culture. Diplomats could easily misrepresent.I would like to thank Sidney Sussex College, Cambridge, St John’s College, Cambridge and the Arts Humanities Research Council for enabling me to undertake this researchThis is the advanced access article published online distributed under a CC BY license, which can also be found on the publisher's website at: http://res.oxfordjournals.org/content/early/2014/06/19/res.hgu043.full.pdf+htm

Gender And Attitude Toward An International Career: A Survey Of Russian Nationals

This paper examines attitudes of Russian MBA students toward international careers and finds that gender is not an issue but that respondents with family constraints were less favorable toward an international career.  Respondents who are male, are single, or do not have children were slightly favorable toward international careers.  Women and respondents with spouses without a career were neutral toward international careers.  Respondents who are married, respondents with children, and respondents with a spouse with a career, were slightly unfavorable toward an international career.  The results of this survey indicate that Russian MBA students are, on average, only slightly favorable toward international careers.  These results contrast with an earlier study that found a stronger preference for international careers among Russian MBA students.  Current MBA students in Moscow have more career opportunities than before.  The results are based on the responses of twenty-nine Russian students in an AACSB accredited MBA program in Moscow who speak both Russian and English and work for an international company or agency

Adding a Brane to the Brane-Anti-Brane Action in BSFT

We attempt to generalize the effective action for the D-brane-anti-D-brane system obtained from boundary superstring field theory (BSFT) by adding an extra D-brane to it to obtain a covariantized action for 2 D-branes and 1 anti-D-brane. We discuss the approximations made to obtain the effective action in closed form. Among other properties, this effective action admits solitonic solutions of codimension 2 (vortices) when one of the D-brane is far separated from the brane-anti-brane pair.Comment: 23 pages, 2 figures, minor revision

Fluid inclusion gas chemistry in east Tennessee Mississippi Valley-type districts: Evidence for immiscibility and implications for depositional mechanisms

Analyses of fluid inclusion gases from Mississippi Valley-type districts in east Tennessee reveal the presence of several distinct aqueous solutions and vapors that were part of the mineralizing process. Inclusion contents were released by crushing 5 to 25 mg mineral samples and by decrepitating individual inclusions; all analyses were obtained by quadrupole mass spectrometry. Most analyzed inclusion fluids consist of H2O with significant amounts of CH4 (0.3 to 2.9 mol%), CO2 (0.1 to 4.7 mol%), and smaller amounts of C2H6, C3H8, H2S, SO2, N2, and Ar. In general, inclusion gas abundances are greatest for sphalerite from the Mascot-Jefferson City district, lower for the Sweetwater district, and lowest for the Copper Ridge district. Compositional similarities in the inclusion fluids from the three districts imply that mineralization probably formed from fluids that permeated the entire region, rather than from completely separate fluids at each site.Saturation pressures calculated for these fluid compositions range from 300 to 2200 bars. Burial depths for the host unit have been estimated to be about 2 to 3 km in the east Tennessee area during Devonian time, the age of mineralization indicated by recent isotopic ages. Pressures at these depths, whether hydrostatic or lithostatic, would not have been adequate to prevent phase separation. Thus, our gas analyses represent either a mixture of vapor-rich and liquid-rich inclusions, or liquid-rich inclusions that trapped excess vapor. A lack of visible vapor-rich inclusions, high gas contents in individual fluid inclusion gas analyses obtained by decrepitation, and a positive correlation between decrepitation temperature and gas content for individual inclusions strongly suggest that the samples contain liquid-rich inclusions that trapped varying amounts of excess vapor. This excess gas probably accounts for the anomalously high homogenization temperatures and the wide range of homogenization temperatures observed in fluid inclusions in these ores. The vapor phase could have formed either by phase separation resulting from over-pressured aqueous fluids migrating into a region of hydrostatic pressure, or by incorporation of a pre-existing gas cap at the sites of deposition into the invading aqueous fluid.Exsolution of a vapor phase from the mineralizing brines should cause precipitation of carbonate and sulfide minerals, but reaction path modelling indicates that the resulting sparry dolomite:sphalerite ratios would be too high to form an ore-grade deposit. On the other hand, if the vapor phase was from a pre-existing sour gas cap that was intercepted by a Zn-rich brine, large amounts of sphalerite would precipitate in a fairly small region. Preliminary mass balance calculations suggest that a gas cap of dimensions similar to the individual districts in east Tennessee could have contained enough H2S to account for the total amount of sphalerite precipitated.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/30308/1/0000710.pd