The thesis presented here is that the result of
engineering is the design, construction, or operation of
systems or their subsystems and components and that the
teaching of systems must be central to engineering education.
It is maintained that current undergraduate engineering
curricula do not give the student adequate appreciation
of this major intellectual element of their profession.
Five proposals for approaches to correct this deficiency
are offered: opportunities for clinical practice throughout
all the undergraduate years; the use of distributed interactive
simulation technology in semester-long projects; courses
or course material on the phenomenology and behavior of
systems; use of project management tools in engineering
clinics; and encouraging engineering faculty to spend some
part of their sabbaticals engaged in system design or operation.
Issues of implementation are addressed, including the scaling
of these ideas to universities that must meet the needs
of large numbers of students.
By means of a technique involving an acoustical resonant cavity, the vibrational relaxation time in nitrogen has been measured at 1186, 1020, 778°K. The lifetime of an excited vibrational level in nitrogen at the above temperatures is found to be 2.29X10 6 , 4.55X10 6 , 6.55X10 6 collisions, respectively. These results are in good agreement with shock-tube measurements of Blackman in the temperature range of 3500-5600 o K. The effect of water vapor on the relaxation time is discussed. Previous measurements by Huber and Kantrowitz are shown to have been affected by water vapor impurities; the present measurements are believed to be relatively free from this effect since the concentration of water vapor was at most 0,005%. design the physical facility and J. Lebel who constructed the electronic control system.
Thirty‐minute simultaneous records of bottom pressure and bottom fluid velocity have been made in 12‐m water depths off Block Island, R. I. Small glass‐enclosed bead thermistors were used in the velocity measurements. Four runs were made with the thermistor at various heights above the sand bottom, ranging from zero to 38cm. These data have been digitized at 1‐sec intervals and analyzed to extract power spectrums and cross spectrums. Both the pressure and the velocity measurements made at a height of 38 cm above the bottom show a typical double‐peak spectrum having maximums at wave periods of 8 and 13 sec. In the peak regions of the spectrum the coherency of the two variables is of the order of 70 to 80 per cent. Quantitatively, the pressure and the velocity power spectrums agree in magnitude to within 30 per cent over the major part of the frequency range. The pressure and the velocity are in phase to within 10° over the major part of the frequency range. Theoretical calculations suggest that at the bottom there is a viscous boundary layer about 0.5 cm thick. Since the thermistor bead is approximately 0.12 cm in diameter, it is capable of resolving a boundary layer of this thickness. Measurements made with the thermistor on the bottom do in fact reveal the presence of such a boundary layer. The operation of the velocity sensor has been checked independently by means of convolution calculations based on the measured bottom pressure.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.