Flight investigation of insect contamination and its alleviation

An investigation of leading edge contamination by insects was conducted with a JetStar airplane instrumented to detect transition on the outboard leading edge flap and equipped with a system to spray the leading edge in flight. The results of airline type flights with the JetStar indicated that insects can contaminate the leading edge during takeoff and climbout. The results also showed that the insects collected on the leading edges at 180 knots did not erode at cruise conditions for a laminar flow control airplane and caused premature transition of the laminar boundary layer. None of the superslick and hydrophobic surfaces tested showed any significant advantages in alleviating the insect contamination problem. While there may be other solutions to the insect contamination problem, the results of these tests with a spray system showed that a continouous water spray while encountering the insects is effective in preventing insect contamination of the leading edges

THE VERTICAL COORDINATION CONTINUUM AND THE DETERMINANTS OF FIRM-LEVEL COORDINATION STRATEGY

A number of past authors have argued that vertical coordination strategies lie along a continuum running from spot markets to vertical integration. However, the strategies that make up the middle of this continuum have remained ill defined and the sense in which the continuum is truly a continuum has not been made specific. This paper attempts to define the continuum and its "middle" strategies in such a manner that the continuum is truly a continuum has not been made specific. This paper attempts to define the continuum and its "middle" strategies in such a manner that the continuum becomes a useful means by which firm-level decision makers could examine their options for vertical coordination strategy.Industrial Organization,

Split-screen single-camera stereoscopic PIV application to a turbulent confined swirling layer with free surface

An annular liquid wall jet, or vortex tube, generated by helical injection inside a tube is studied experimentally as a possible means of fusion reactor shielding. The hollow confined vortex/swirling layer exhibits simultaneously all the complexities of swirling turbulence, free surface, droplet formation, bubble entrapment; all posing challenging diagnostic issues. The construction of flow apparatus and the choice of working liquid and seeding particles facilitate unimpeded optical access to the flow field. A split-screen, single-camera stereoscopic particle image velocimetry (SPIV) scheme is employed for flow field characterization. Image calibration and free surface identification issues are discussed. The interference in measurements of laser beam reflection at the interface are identified and discussed. Selected velocity measurements and turbulence statistics are presented at Re_λ = 70 (Re = 3500 based on mean layer thickness)

STRATEGIC CHOICE ALONG THE VERTICAL COORDINATION CONTINUUM

Fundamental changes are underway in the U.S. agri-food system, changes that are altering traditional marketing relationships. Parts of the food system are becoming tightly integrated, such as the poultry subsector and, increasingly, the pork subsector. The tightening of vertical linkages has been characterized by movement from open markets to various forms of managed coordination, e.g. contracting, strategic alliances, and single ownership of multiple market stages. 1998 AAEA SymposiumIndustrial Organization,

ESTIMATION OF DEMAND FOR WHEAT BY CLASSES FOR THE UNITED STATES AND THE EUROPEAN UNION

This study estimates demand for wheat differentiated by classes using a dynamic AIDS model for the United States and the European Union (EU). The results suggest that imported wheat is more price responsive than domestic wheat in the U.S. market but not in the EU market. This may suggest that the Canadian policy that reduces prices of Canadian wheat in the U.S. market or U.S. export subsidies that raise prices of U.S, wheat could be expected to give rise to substantial substitution of Canadian for U.S. wheat. It is also found that in the EU, complementary relationships exist between spring and other wheat groups, This complementary relationship between the lower and higher quality wheat in the EU is not surprising because EU millers blend cheaper wheat such as EU common wheat and U.S. other wheat with high protein (spring) to obtain the preferred characteristics.Crop Production/Industries, Demand and Price Analysis,

WHAT BUYERS ARE SAYING ABOUT MICHIGAN CELERY

Food Consumption/Nutrition/Food Safety,

Meteoroid detector

A meteoroid detector is described which uses, a cold cathode discharge tube with a gas-pressurized cell in space for recording a meteoroid puncture of the cell and for determining the size of the puncture