
UF Chemical Engineering > People > Faculty > Oscar D. Crisalle
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Oscar D. Crisalle
Ph.D.,1990,University of California-Santa
Barbara |
| Professor |
Ph : 352-392-5120
crisalle@che.ufl.edu
429 Chemical Engineering Building |
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| Areas |
| Analysis and design of control systems |
| Real-time remote control over the Internet |
| Manufacture of photovoltaic devices |
| Control of fuel-cell powered
systems |
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| Analysis and Design of Control Systems |
| Keywords : Process Control |
Models of processing systems only approximate physical
reality. A major challenge addressed by our research is
the design of controllers that, in spite of the uncertainty
present in the model, can deliver high performance and also
guarantee stable behavior. Such controllers are called robust.
The effort focuses on the synthesis of robust controllers
using methodologies such as pole-placement, predictive-control,
and frequency-domain techniques based on the novel concept
of a Nyquist Robust Stability Margin
proposed by our group.
Since many processes of interest are inherently nonlinear,
controllers designed using linear systems theory may experience
severe performance degradation. Appropriate control designs
that address relevant nonlinear features are needed. We
are investigating the use of new methods for the analysis
and design of adaptive, predictive, and sliding-mode control
strategies, and the integration of the resulting techniques
within the framework of computer aided tools.
We are developing technologies that enable the operation
of control laboratory facilities in real time by students
in geographically remote locations. The user accesses the
laboratory using the Internet and a standard web browser,
and can introduce manipulations and observe the response
of the physical system. Applications of these research results
include educational programs, as well as technology that
allows the operation of complex chemical plants by personnel
located in other parts of the world. |
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| Control of Fuel-Cell Powered Systems |
| Keywords : Process Control, Energy |
| One of our research branches focuses on the technological
challenges posed by systems powered by fuel cells. In particular,
transportation vehicles with on-board hydrogen generation
which require the deployment of effective multivariable and
highly coupled control strategies that operate at different
time scales. For example, the response time of the fuel cell
is faster than that of an on-board methanol reformer, though
it is slower than the response of the back-up battery systems
in the vehicle. Multivariable predictive control techniques
are being developed to support the key requirements of this
technology, with an emphasis on fuel-cell-powered urban buses
for passenger transportation. |
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| Manufacture of Thin-Film Photovoltaic Devices |
| Keywords : Energy, Materials/Devices |
| Our team is investigating novel photo-absorber materials
that we synthesize and using a plasma migration-enhanced epitaxial
growth reactor capable of growing single-crystal thin films.
In addition, photovoltaic buffer films are grown and optimized
using chemical bath deposition methods, and transparent conducting
oxides are deposited via magnetron sputtering methods, giving
our group full capabilities for manufacturing and characterizing
thin-film photovoltaic cells that achieve desirable solar-energy-to-electricity
conversion efficiencies. |
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| Recent Publications |
| 1. |
Kim, W.K., Payzant, E.A., Kim, S., Speakman,
S.A., Crisalle, O.D. and Anderson, T.J., “Reaction
Kinetics of CuGaSe2 Formation from a GaSe/CuSe Bilayer
Precursor Film,” Journal of Crystal Growth, 310(10)
(2008) 2987. |
| 2. |
Jung, K., Hayden, L.A., Crisalle, O.D.,
Eisenstadt, W.R., Fox, R.M., Navratil, P., Campbell,
R.L., McCuen, C. and Lewis, M., “A New Characterization
and Calibration Method for 3 dB-Coupled On-Wafer Measurements,”
IEEE Transactions on Microwave Theory and Techniques,
56(5) (2008) 1193. |
| 3 |
Braatz, R.D. and Crisalle, O.D., “Chemical
Process Control,” International Journal of Robust
and Nonlinear Control, 17(13) (2007) 1161. |
| 4. |
Kim, W.K., Payzant, E.A., Anderson, T.J.
and Crisalle, O.D., “In Situ Investigation of
the Selenization Kinetics of Cu-Ga Precursors using
Time-Resolved High-Temperature X-ray Diffraction,”
Thin Solid Films, 515 (2007) 5837. |
| 5. |
Al-Shamali, S.A. Ji, B., Crisalle, O.D.,
and Latchman, H.A., “The Nyquist Robust Sensitivity
Margin for Uncertain Closed-Loop Systems,” International
Journal of Robust and Nonlinear Control, 15, (2005)
619. |
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