42,042 research outputs found

    The Deskilling vs Upskilling Debate: The Role of BLS Projections

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    [Excerpt] The growing shortage of professionally trained workers and the rising skill premiums will tend to cause supply to increase more rapidly than we have projected. But the gap between the projected growth of demand and supply is huge. Just to maintain the balance between the growth of supply and the growth of occupational demand that prevailed in the 1980s, itself a period of shortage, it will be necessary to increase in the stock of college graduates in the year 2000 by 3.7 million or, put another way, to raise the number of college graduates entering the labor forces by 462,000 or 42 percent between 1992 and the year 2000

    The Worsening Shortage of College-Graduate Workers

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    The Bureau of Labor Statistics (BLS) projections of occupational employment growth have consistently underpredicted the growth of skilled occupations. BLS currently projects that professional, technical, and managerial jobs will account for 44.5% of employment growth between 1988 and 2000, while we project they will account for 70% of employment growth. Between March 1988 and March 1991 these occupations, in fact, accounted for 87% of employment growth. The BLS\u27s projections of the supply/demand balance for college graduates have also been off the mark-predicting a surplus for the 1980s when, in fact, a shortage developed, and relative wage ratios for college graduates rose to all-time highs. We project that the supply of college educated workers will grow more slowly during the 1990s and that there will be a continuing escalation of wage premiums for college graduates

    Chaotic string-capture by black hole

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    We consider a macroscopic charge-current carrying (cosmic) string in the background of a Schwarzschild black hole. The string is taken to be circular and is allowed to oscillate and to propagate in the direction perpendicular to its plane (that is parallel to the equatorial plane of the black hole). Nurmerical investigations indicate that the system is non-integrable, but the interaction with the gravitational field of the black hole anyway gives rise to various qualitatively simple processes like "adiabatic capture" and "string transmutation".Comment: 13 pages Latex + 3 figures (not included), Nordita 93/55

    Thermodynamic and transport properties of frozen and reacting pH2-oH2 mixtures

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    Application of experimental state data and spectroscopic term values shows that the thermodynamic and transport properties of reacting pH2-oH2 mixtures are considerably different than those of chemically frozen pH2 at temperatures below 300 R. Calculated H-S data also show that radiation-induced pH2-oH2 equilibration at constant enthalpy produces a temperature drop of at least 28 R, corresponding to an ideal shaft work loss of 15% or more for a turbine operating downstream from the point of conversion. Aside from differences in thermodynamic and transport properties, frozen pH2-oH2 mixtures may differ from pure pH2 on a purely hydrodynamical basis

    Winter ozone formation and VOC incremental reactivities in the Upper Green River Basin of Wyoming

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    The Upper Green River Basin (UGRB) in Wyoming experiences ozone episodes in the winter when the air is relatively stagnant and the ground is covered by snow. A modeling study was carried out to assess relative contributions of oxides of nitrogen (NO_x) and individual volatile organic compounds (VOCs), and nitrous acid (HONO) in winter ozone formation episodes in this region. The conditions of two ozone episodes, one in February 2008 and one in March 2011, were represented using a simplified box model with all pollutants present initially, but with the detailed SAPRC-07 chemical mechanism adapted for the temperature and radiation conditions arising from the high surface albedo of the snow that was present. Sensitivity calculations were conducted to assess effects of varying HONO inputs, ambient VOC speciation, and changing treatments of temperature and lighting conditions. The locations modeled were found to be quite different in VOC speciation and sensitivities to VOC and NO_x emissions, with one site modeled for the 2008 episode being highly NO_x-sensitive and insensitive to VOCs and HONO, and the other 2008 site and both 2011 sites being very sensitive to changes in VOC and HONO inputs. Incremental reactivity scales calculated for VOC-sensitive conditions in the UGRB predict far lower relative contributions of alkanes to ozone formation than in the traditional urban-based MIR scale and that the major contributors to ozone formation were the alkenes and the aromatics, despite their relatively small mass contributions. The reactivity scales are affected by the variable ambient VOC speciation and uncertainties in ambient HONO levels. These box model calculations are useful for indicating general sensitivities and reactivity characteristics of these winter UGRB episodes, but fully three-dimensional models will be required to assess ozone abatement strategies in the UGRB

    Status, distribution and use of threatened tree species in the walnut-fruit forests of Kyrgyzstan

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    Information is lacking on the status of threatened tree species in Central Asia. This paper aims to provide preliminary information for 10 fruit and nut tree species of Kyrgyzstan. A field survey was conducted throughout the range of walnut-fruit forests in this country, supported by a socio-economic survey. Results indicated that species differed markedly in abundance. Whereas Malus sieversii was found in all locations, four species (Crataegus pontica,Pistacia vera,Pyrus korshinskyi and Sorbus persica) were only found in a minority (≤ 30%) of sites. Four species showed evidence of a bimodal distribution of stem diameters, which could be attributed to fuelwood harvesting, as indicated by the socio-economic survey. A majority of respondents reported a decline in the available grazing resource, a decline in the availability of harvested fruits and an increase in time required to collect fuelwood over the past decade. These results suggest that unsustainable land-use practices may be impacting negatively on populations of threatened fruit tree species. These results highlight the need to regulate local forest use to ensure that threatened fruit and nut tree species are effectively conserved, and the need for targeted actions to conserve the most threatened species, such as P. korshinskyi. © 2014 © 2014 Taylor & Francis

    NASTRAN data generation of helicopter fuselages using interactive graphics

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    The development and implementation of a preprocessor system for the finite element analysis of helicopter fuselages is described. The system utilizes interactive graphics for the generation, display, and editing of NASTRAN data for fuselage models. It is operated from an IBM 2250 cathode ray tube (CRT) console driven by an IBM 370/145 computer. Real time interaction plus automatic data generation reduces the nominal 6 to 10 week time for manual generation and checking of data to a few days. The interactive graphics system consists of a series of satellite programs operated from a central NASTRAN Systems Monitor. Fuselage structural models including the outer shell and internal structure may be rapidly generated. All numbering systems are automatically assigned. Hard copy plots of the model labeled with GRID or elements ID's are also available. General purpose programs for displaying and editing NASTRAN data are included in the system. Utilization of the NASTRAN interactive graphics system has made possible the multiple finite element analysis of complex helicopter fuselage structures within design schedules

    Workshop on Applications of Phase Diagrams in Metallurgy and Ceramics

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    A workshop was held to assess the current national and international status of phase diagram determinations and evaluations for alloys, ceramics, and semiconductors; to determine the needs and priorities, especially technological, for phase diagram determinations and evaluations; and to estimate the resources being used and potentially available for phase diagram evaluation. Highlights of the workshop, description of a new poster board design used in the poster sessions, lists of attendees and demonstrations, the program, and descriptions of the presentations are included

    Thomas-forbidden particle capture

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    At high energies, in particle-capture processes between ions and atoms, classical kinematic requirements show that generally double collision Thomas processes dominate. However, for certain mass-ratios these processes are kinematically forbidden. This paper explores the possibility of capture for such processes by triple or higher order collision processes.Comment: 34 pages and three figure

    Low speed aerodynamic characteristics of the GD/C B-18E3 booster

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    A 0.02 scale model of the B-18E3 space shuttle booster was tested in a low speed wind tunnel to evaluate the low speed aerodynamic charactersitics. The basic configuration, including build-up, was tested at a Mach number of 0.201 and Reynolds number per foot of 1.39 million. The normal angle-of-attack range was -4 to +24 degrees in 2 degree increments, at sideslip angles of 0 and 5 degrees. Some lateral data were obtained at the sideslip angle range of -6 to 10 degrees at angles-of attack of 0, 10, and 15 degrees. Data were obtained for canard, split elevon, and split rudder deflections
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