Exhaust cloud rise and diffusion in the atmosphere

Analytical approach develops physical-mathematical model of rocket engine exhaust cloud rise, growth, and diffusion. Analytic derivations and resultant model apply to hot exhaust cloud study or industrial stack plumes, making work results applicable to air pollution. Model formulations apply to all exhaust cloud types and various atmospheric conditions

Experimental dynamic stiffness and damping of externally pressurized gas-lubricated journal bearings

A rigid vertical shaft was operated with known amounts of unbalance at speeds to 30,000 rpm and gas supply pressure ratios to 4.8. From measured amplitude and phase angle data, dynamic stiffness and damping coefficients of the bearings were determined. The measured stiffness was proportional to the supply pressure, while damping was little affected by supply pressure. Damping dropped rapidly as the fractional frequency whirl threshold was approached. A small-eccentricity analysis overpredicted the stiffness by 20 to 70 percent. Predicted damping was lower than measured at low speeds but higher at high speeds

Rise and growth of space vehicle engine exhaust and associated diffusion models

Space vehicle plume rise and associated diffusion models at Cape Kennedy Launch Comple

Recent Structural Change in the U.S. Farm Sector: A Household Income Equivalency Perspective

Structural change in the U.S. farm sector remains a source of continuing national interest. This interest has been heightened recently by concern over vertical integration and the passage of a new farm bill. Structural change is commonly examined in terms of the scale of the farm, such as the dollar value of sales or the number of acres farmed. However, to many farmers and non-farmers, structural change is not about physical or financial scale, but about the ability of the farm to provide an acceptable standard of living relative to other Americans. In this article, we use a household income equivalency perspective to examine recent changes in farm structure. The picture which emerges differs from the conventionally accepted story in several respects

UPDATING CORN PROGRAM PAYMENT YIELDS: ARE FARM OPERATORS DIFFERENTIALLY AFFECTED?

Crop yields which determine farm income deficiency payments have been frozen at 1981-1985 levels since 1986. Data from a longitudinal survey of Ohio farm operators are analyzed to evaluate whether updating payment yields will differentially affect farm operators. Results of the analysis imply that farm operators who operate larger farms, live in counties with higher yields, and have higher fertilizer and pesticide expenses per acre of corn will benefit more. In addition, low (high) existing payment yields are understated (overstated) relative to updated payment yields.Agricultural Finance,

Use of ERTS-1 data in the educational and applied research programs of agricultural extension

There are no author-identified significant results in this report

Integrating Writing To Improve Math Achievement

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