27,946 research outputs found
A Hands-On, Active Learning Approach to Increasing Manufacturing Knowledge in Engineering Students
This paper describes a new learning module implemented as part of the senior capstone design course at Marquette University to teach engineering students about basic manufacturing processes, lean manufacturing principles, and design for manufacturability. The module includes several examples of active and student centered learning as part of an in-class assembly line simulation exercise. Students reflected on this experience, and suggested process improvements to save time, reduce cost and waste, and improve the assembly line process. They learned of the importance of manufacturing documentation, process design, and design for assembly. At the end of the module, students understood the importance of designing a product not only for the end user, but also for the assemblers and inspectors. Details of the module design and implementation will be presented along with comments from students
Evidence of Skyrmion excitations about in n-Modulation Doped Single Quantum Wells by Inter-band Optical Transmission
We observe a dramatic reduction in the degree of spin-polarization of a
two-dimensional electron gas in a magnetic field when the Fermi energy moves
off the mid-point of the spin-gap of the lowest Landau level, . This
rapid decay of spin alignment to an unpolarized state occurs over small changes
to both higher and lower magnetic field. The degree of electron spin
polarization as a function of is measured through the magneto-absorption
spectra which distinguish the occupancy of the two electron spin states. The
data provide experimental evidence for the presence of Skyrmion excitations
where exchange energy dominates Zeeman energy in the integer quantum Hall
regime at
Using giant scarlet runner bean embryos to uncover regulatory networks controlling suspensor gene activity.
One of the major unsolved issues in plant development is understanding the regulatory networks that control the differential gene activity that is required for the specification and development of the two major embryonic regions, the embryo proper and suspensor. Historically, the giant embryo of scarlet runner bean (SRB), Phaseolus coccineus, has been used as a model system to investigate the physiological events that occur early in embryogenesis-focusing on the question of what role the suspensor region plays. A major feature distinguishing SRB embryos from those of other plants is a highly enlarged suspensor containing at least 200 cells that synthesize growth regulators required for subsequent embryonic development. Recent studies have exploited the giant size of the SRB embryo to micro-dissect the embryo proper and suspensor regions in order to use genomics-based approaches to identify regulatory genes that may be involved in controlling suspensor and embryo proper differentiation, as well as the cellular processes that may be unique to each embryonic region. Here we review the current genomics resources that make SRB embryos a compelling model system for studying the early events required to program embryo development
Exact Nonperturbative Unitary Amplitudes for 1->N Transitions
I present an extension to arbitrary N of a previously proposed field
theoretic model, in which unitary amplitudes for processes were
obtained. The Born amplitude in this extension has the behavior
expected in a bosonic field theory. Unitarity
is violated when , or when Numerical
solutions of the coupled Schr\"odinger equations shows that for weak coupling
and a large range of N>\ncrit, the exact unitary amplitude is reasonably fit
by a factorized expression |A(1->N)| \sim (0.73 /N) \cdot \exp{(-0.025/\g2)}.
The very small size of the coefficient 1/\g2 , indicative of a very weak
exponential suppression, is not in accord with standard discussions based on
saddle point analysis, which give a coefficient The weak dependence
on could have experimental implications in theories where the exponential
suppression is weak (as in this model). Non-perturbative contributions to
few-point correlation functions in this theory would arise at order $K\ \simeq\
\left((0.05/\g2)+ 2\ ln{N}\right)/ \ ln{(1/\g2)}\g2.$Comment: 11 pages, 3 figures (not included
A modeling analysis program for the JPL Table Mountain Io sodium cloud data
Progress and achievements in the second year are discussed in three main areas: (1) data quality review of the 1981 Region B/C images; (2) data processing activities; and (3) modeling activities. The data quality review revealed that almost all 1981 Region B/C images are of sufficient quality to be valuable in the analyses of the JPL data set. In the second area, the major milestone reached was the successful development and application of complex image-processing software required to render the original image data suitable for modeling analysis studies. In the third area, the lifetime description of sodium atoms in the planet magnetosphere was improved in the model to include the offset dipole nature of the magnetic field as well as an east-west electric field. These improvements are important in properly representing the basic morphology as well as the east-west asymmetries of the sodium cloud
A modeling analysis program for the JPL table mountain Io sodium cloud
Progress and achievements in the first year are discussed in three main areas: (1) review and assessment of the massive JPL Table Mountain Io sodium cloud data set, (2) formulation and execution of a plan to perform further processing of this data set, and (3) initiation of modeling activities. The complete 1976-79 and 1981 data sets are reviewed. Particular emphasis is placed on the superior 1981 Region B/C images which provide a rich base of information for studying the structure and escape of gases from Io as well as possible east-west and magnetic longitudinal asymmetries in the plasma torus. A data processing plan is developed and is undertaken by the Multimission Image Processing Laboratory of JPL for the purpose of providing a more refined and complete data set for our modeling studies in the second year. Modeling priorities are formulated and initial progress in achieving these goals is reported
A modeling analysis program for the JPL table mountain Io sodium cloud
A data quality review for the entire set of the 1981 Region B/C images has been completed and is presented. The review indicates that almost all images are of sufficient quality to be valuable in our analysis of this data set. Five data-correlation studies for the same data set have also been completed and are useful in classifying and studying the sodium cloud morphology and its interactions with solar radiation pressure and the plasma torus. Additional progress in developing new image processing techniques and in improving the Io sodium cloud model is also discussed
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