Experimental investigation of the effect of general imperfections on the buckling of cylindrical shells

Imperfection survey data on cylindrical shells before and during axial compression loading up to buckling loa

A Multimode Analysis for Calculating Buckling Loads of Imperfect Cylindrical Shells

By expanding the response of a cylindrical shell in truncated Fourier series, the nonlinear Donnell type shell equations for imperfect stiffened shells were reduced to a set of linear equations in the correction terms by Newton's method of quasilinearization. Solutions were obtained for isotropic and for ring and stringer stiffened shells. The amplitudes of the initial imperfections used in the analysis were calculated from the corresponding Imbert-Donnell imperfection models. The free parameters in this imperfection model were obtained by least square fitting the harmonics of the experimentally measured initial imperfections. It was possible in all cases to achieve satisfactory correlation using only a few suitably chosen deflection and imperfection modes

The Vatard Sisters

Les Soeurs Vatard, described by its author as a “lewd but exact” slice of life, was J.-K. Huysmans’ second novel. Huysmans abandoned poetry and turned to the novel at a time when the works of Emile Zola were intensely controversial; Les Soeurs Vatard is dedicated to Zola by his fervent admirer and devoted friend. In it, Huysmans vividly depicts the scene that for his generation of French writers stood for the contemporary world: the brutal, teeming life of the industrial quarters of Paris in the 1870s. Huysmans’ Vatard sisters are “Désirée, an urchin of fifteen, a brunette with large, pale eyes that were somewhat crossed, plump without being fat, attractive and clean; and Céline, the carouser, a big girl with clear eyes and hair the color of straw, a solid, vigorous girl whose blood raced and danced in her veins. The two are part of that “bizarre race of young women” who work as bookbinders, whose lives revolve around the gaslighted bindery works, the gaudy shop windows, and cheap wineshops that Huysmans describes with minute and colorful detail. His precisely observed sketches show that Naturalism as practiced by Buysmans had none of Zola\u27 s emphasis on “scientific” determinism, but centered primarily on the faithful rendering of what he described as “living persons in real milieus.” The Vatard Sisters is the first English translation of Les Soeurs Vatard. James C. Babcock is professor of French at Western Kentucky University.https://uknowledge.uky.edu/upk_french_and_francophone_literature/1005/thumbnail.jp

AN ANALYSIS OF REGIONAL ECONOMIC GROWTH IN THE US MIDWEST

In this paper we examine more closely some of the forces that underlie economic growth at the county level. In an effort to describe a much more comprehensive regional economic growth model, we address a variety of different growth hypotheses by introducing a large number of growth related variables. When formulating our hypotheses and specifying our growth model we make liberal use of GIS mapping software to "paint" a picture of where growth spots exist and why. Our empirical estimation indicates amenities, state and local tax burdens, population, amount of agricultural activity, and demographics have important economic growth impacts.Community/Rural/Urban Development,

A Computational Comparison of Optimization Methods for the Golomb Ruler Problem

The Golomb ruler problem is defined as follows: Given a positive integer n, locate n marks on a ruler such that the distance between any two distinct pair of marks are different from each other and the total length of the ruler is minimized. The Golomb ruler problem has applications in information theory, astronomy and communications, and it can be seen as a challenge for combinatorial optimization algorithms. Although constructing high quality rulers is well-studied, proving optimality is a far more challenging task. In this paper, we provide a computational comparison of different optimization paradigms, each using a different model (linear integer, constraint programming and quadratic integer) to certify that a given Golomb ruler is optimal. We propose several enhancements to improve the computational performance of each method by exploring bound tightening, valid inequalities, cutting planes and branching strategies. We conclude that a certain quadratic integer programming model solved through a Benders decomposition and strengthened by two types of valid inequalities performs the best in terms of solution time for small-sized Golomb ruler problem instances. On the other hand, a constraint programming model improved by range reduction and a particular branching strategy could have more potential to solve larger size instances due to its promising parallelization features

Astrometric-spectroscopic determination of the absolute masses of the HgMn binary star Phi Herculis

The Mercury-Manganese star Phi Her is a well known spectroscopic binary that has been the subject of a recent study by Zavala et al. (2006), in which they resolved the companion using long-baseline interferometry. The total mass of the binary is now fairly well established, but the combination of the spectroscopy with the astrometry has not resulted in individual masses consistent with the spectral types of the components. The motion of the center of light of Phi Her was clearly detected by the Hipparcos satellite. Here we make use of the Hipparcos intermediate data (`abscissa residuals') and show that by combining them in an optimal fashion with the interferometry the individual masses can be obtained reliably using only astrometry. We re-examine and then incorporate existing radial-velocity measurements into the orbital solution, obtaining improved masses of 3.05 +/- 0.24 M_Sun and 1.614 +/- 0.066 M_Sun that are consistent with the theoretical mass-luminosity relation from recent stellar evolution models. These mass determinations provide important information for the understanding of the nature of this peculiar class of stars.Comment: Total of 18 pages including figures and tables, in emulateapj format. To appear in The Astronomical Journal, June 2007 issu

Evaluation of aircraft microwave data for locating zones for well stimulation and enhanced gas recovery

Imaging radar was evaluated as an adjunct to conventional petroleum exploration techniques, especially linear mapping. Linear features were mapped from several remote sensor data sources including stereo photography, enhanced LANDSAT imagery, SLAR radar imagery, enhanced SAR radar imagery, and SAR radar/LANDSAT combinations. Linear feature maps were compared with surface joint data, subsurface and geophysical data, and gas production in the Arkansas part of the Arkoma basin. The best LANDSAT enhanced product for linear detection was found to be a winter scene, band 7, uniform distribution stretch. Of the individual SAR data products, the VH (cross polarized) SAR radar mosaic provides for detection of most linears; however, none of the SAR enhancements is significantly better than the others. Radar/LANDSAT merges may provide better linear detection than a single sensor mapping mode, but because of operator variability, the results are inconclusive. Radar/LANDSAT combinations appear promising as an optimum linear mapping technique, if the advantages and disadvantages of each remote sensor are considered

An Analysis of Regional Economic Growth in the U.S. Midwest

In this paper we examine some of the economic forces that underlie economic growth at the county level. In an effort to describe a much more comprehensive regional economic growth model, we address a variety of different growth hypotheses by introducing a large number of growth related variables. When formulating our hypotheses and specifying our growth model we make liberal use of GIS (geographical information systems) mapping software to paint a picture of where growth spots exist. Our empirical estimation indicates that amenities, state and local tax burdens, population, amount of primary agriculture activity, and demographics have important impacts on economic growth

Economic Perspectives on GMO Market Segregation

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