The engineering professor's role is dualistic in the sense that not only must s/he create an academic environment conducive to the acquisition of course content but must also prepare students to become practicing professionals. This dualism requires that the professor both motivate good study habits as well as build within students the confidence that they have the requisite capability to perform actual engineering. Self-efficacy, simply defined as one's self-judgment concerning capability, has been shown to be an important mediating factor in cognitive motivation. This paper describes the motivating role of the professor, theories of motivation, the role of self-efficacy in motivation, and guiding principles that can be used to enhance self-efficacy in engineering students. These principles can serve as guidelines in designing instructional delivery strategies that motivate engineering students to engage in behaviors conducive to becoming value-added practitioners.

The phenomenon of twin supersonic plume resonance is defined and studied as it pertains to high-level dynamic loads in the internozzle region of aircraft like the F-15 and B-1B. Using a l/40th-scale-model twin jet nacelle with powered choked nozzles, it is found that intense internozzle dynamic pressures are associated with the phased coupling of each plume's large-scale structure. This condition is most prevalent when each plume's large-scale structure has constituent elements composed of the B-type helical instabilities. The coupling of each plume's large-scale structure forces each plume to flap spatially in a preferred direction. Suppression of these dynamic loads was accomplished by simple geometric modifications to only one plume's nozzle. These modifications disrupt the natural selection of the B-type mode and thereby decouple the plumes. NomenclatureD = jet exit diameter Dj = fully expanded jet plume diameter, Eq. (4) f s = plume resonance frequency L = average plume shock cell spacing, Eq. (5) M c = convection Mach number large scale structure M d = nozzle design Mach number MJ = fully expanded plume Mach number St = Strouhal number, Eq. (3) V c = convection velocity of large-scale structure Vj = fully expanded jet plume velocity 7= ratio of specific heats X = acoustic wavelength

The near field fluctuating pressure of a cold subsonic jet (Mach 0.85) issuing from a contoured convergent nozzle was studied. Conventional time series analysis (i.e., correlation and spectral analysis) as well as a wavelet analysis were used to characterize time-dependent events thereby revealing features consistent with current understandings of jet noise while also uncovering modal features consistent with previous measurements of the jet flow field itself. Specifically, the measurements reveal extensive sources of multiple frequencies in the streamwise direction. The near field information of the present investigation should help to bridge our understanding of the relationship between the velocity field and the far field acoustic emission associated with subsonic jet noise as well as supply a data set that can be used for verification of computational efforts.

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The authors explored the relationship between the career aspirations of 89 preadolescents from low socioeconomic backgrounds and the actual occupations of the working adults in their homes with regard to status, job gender identification, and interest (Holland, 1997). There was a significant relationship between boys’ career aspirations and the occupations of the working male adults in their homes, specifically job gender identification and interest. More adult males had stereotypically male jobs—classified as Realistic by Holland (1997)—that was mirrored in the preadolescent boys’ career aspirations. There were no significant matches between the boys and working women or with the girls and the working adults of either gender.