Development of a Cheap Helicopter Assisted Landing System Method

Abstract This paper presents a relatively cheap helicopter assisted landing system concept. A frequency modulated continuous radar (FMCWR) is used to check an unprepared landing area for the presence of interfering objects. The spectrum processing of the converted signal is used to provide multi target resolution. The experimental research is done by using a 4.3 GHz FMCWR radar. The converted signal spectra are provided for mirror and rough surfaces, as well for multiple targets in a case of interfering object existence.

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Secondary flows in ducts of square cross-section

Journal of Fluid Mechanics ◽

10.1017/s0022112072000680 ◽

1972 ◽

Vol 54 (2) ◽

pp. 289-295 ◽

Cited By ~ 89

Author(s):

B. E. Launder ◽

W. M. Ying

Keyword(s):

Secondary Flow ◽

Cross Section ◽

Experimental Research ◽

Friction Velocity ◽

Rough Surfaces ◽

Axial Flow ◽

Secondary Flows ◽

Main Emphasis

The paper presents the outcome of experimental research on turbulence-induced secondary flows in square-sectioned ducts. The main emphasis of the experiments has been on the measurement of the secondary flows in a duct with equally roughened surfaces. Here the secondary flow is a substantially larger proportion of the axial flow than is the case in smooth-walled ducts. With the secondary velocities normalized by the friction velocity, however, the resultant profiles for smooth and rough surfaces are the same, within the precision of the measurements.

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Secondary Transfer Effect of Contact

Social Psychology ◽

10.1027/1864-9335.40.2.55 ◽

2009 ◽

Vol 40 (2) ◽

pp. 55-65 ◽

Cited By ~ 146

Author(s):

Thomas F. Pettigrew

Keyword(s):

Cognitive Dissonance ◽

Experimental Research ◽

Intergroup Contact ◽

Transfer Effect ◽

Evaluative Conditioning ◽

Transfer Effects ◽

Secondary Transfer ◽

Primary Reduction

This paper reviews the evidence for a secondary transfer effect of intergroup contact. Following a contact’s typical primary reduction in prejudice toward the outgroup involved in the contact, this effect involves a further, secondary reduction in prejudice toward noninvolved outgroups. Employing longitudinal German probability samples, we found that significant secondary transfer effects of intergroup contact exist, but they were limited to specific outgroups that are similar to the contacted outgroup in perceived stereotypes, status or stigma. Since the contact-prejudice link is bidirectional, the effect is inflated when prior prejudice reducing contact is not controlled. The strongest evidence derives from experimental research. Both cognitive (dissonance) and affective (evaluative conditioning) explanations for the effect are offered.

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