Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 11 of 11

Full-Text Articles in Engineering

Applicationofspectroscopic Ellipsometry To In-Stu. Real-Time Fabrication Of Multiple Layer Alternating High/Low Refractive Index Filters, Blaine D. Johs, Jeffery S. Hale, John A. Woollam, Craig M. Herzinger Sep 2005

Applicationofspectroscopic Ellipsometry To In-Stu. Real-Time Fabrication Of Multiple Layer Alternating High/Low Refractive Index Filters, Blaine D. Johs, Jeffery S. Hale, John A. Woollam, Craig M. Herzinger

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed is application of oblique angle of incidence, reflection and/or transmission mode spectroscopic ellipsometry PSI and/or DELTA, (including combinations thereof and/or mathematical equivalents), vs. wavelength data to monitor and/or control fabrication of multiple layer high/low refractive index band-pass, band-reject and varied attenuation vs. wavelength filters, either alone or in combination with transmissive non-ellipsometric electromagnetic beam turning point vs. layer data obtained at an essentially normal angle of incidence.


System And Method Enabling Simultaneous Investigation Of Sample With Two Beams Of Electromagnetic Radiation, John A. Woollam, Galen L. Pfeiffer, Daniel W. Thompson, Blaine D. Johs, Craig M. Herzinger Aug 2005

System And Method Enabling Simultaneous Investigation Of Sample With Two Beams Of Electromagnetic Radiation, John A. Woollam, Galen L. Pfeiffer, Daniel W. Thompson, Blaine D. Johs, Craig M. Herzinger

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed are system and method for a characterizing system consisting of a fluid sample on a two-sided stage, utilizing data obtained by applying, from both sides thereof, beams of electromagnetic radiation to a fluid coated surface in a containing cell volume. The beams can have the same or different wavelength content and/or polarization state and can be applied at the same or different magnitude angles-of-incidence, and a third typically unpolarized beam can be applied at a normal angle-of-incidence.


System And Method Enabling Simultaneous Investigation Of Sample With Two Beams Of Electromagnetic Radation, John A. Woollam, Galen L. Pfeiffer, Daniel W. Thompson, Blaine D. Johs, Craig M. Herzinger Aug 2005

System And Method Enabling Simultaneous Investigation Of Sample With Two Beams Of Electromagnetic Radation, John A. Woollam, Galen L. Pfeiffer, Daniel W. Thompson, Blaine D. Johs, Craig M. Herzinger

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed are System and method for characterizing a System consisting of a fluid Sample on a two sided Stage, utilizing data obtained by applying, from both sides thereof, beams of electromagnetic radiation to a fluid coated Surface in a containing cell Volume. The beams can have the same or different wavelength content and/or polarization State, and can be applied at the same or different magnitude angles-of-incidence, and a third typically unpolarized beam can be applied at a normal angle-of-incidence.


Multi-Aoi-System For Easy Changing Angles Of Incidence In Ellipsometer, Polarimeter And Reflectometer Systems, Blaine D. Johs, Ping He, Martin M. Liphardt, Christopher A. Goeden, John A. Woollam, James D. Welch Feb 2005

Multi-Aoi-System For Easy Changing Angles Of Incidence In Ellipsometer, Polarimeter And Reflectometer Systems, Blaine D. Johs, Ping He, Martin M. Liphardt, Christopher A. Goeden, John A. Woollam, James D. Welch

Department of Electrical and Computer Engineering: Faculty Publications

Disclosed is a system for enabling easy sequential setting of different Angles-of-Incidence of a beam of electromagnetic radiation to a surface of a sample system, and to regression based methodology for evaluating and compensating the effects of the presence of electromagnetic beam intercepting angle-of-incidence changing systems, including where desired, parameterization of calibration parameters.


Editorial, Robert W. Stewart, Michael W. Hoffman, Stephan Weiss Jan 2005

Editorial, Robert W. Stewart, Michael W. Hoffman, Stephan Weiss

Department of Electrical and Computer Engineering: Faculty Publications

In the past years, digital signal processing (DSP) algorithms and architectures for baseband communication systems have fuelled the delivery of applications such as 3G mobile communications and wireless LAN to mass markets. This was made possible by a tremendous growth in the performance of computational devices such as digital signal processors and FPGAs, as well as an increase in sampling rates of conversion devices to potentially several 100 MHz. While the development of both computational devices and ADCs/DACs continues, thus permitting DSP to be applied at IF sampling rates and possibly beyond, the opportunities for further enhancing radio devices by …


Comparison Of Antenna Array Systems Using Ofdm For Software Radio Via The Sibic Model, Khoi D. Le, Michael W. Hoffman, Robert D. Palmer Jan 2005

Comparison Of Antenna Array Systems Using Ofdm For Software Radio Via The Sibic Model, Khoi D. Le, Michael W. Hoffman, Robert D. Palmer

Department of Electrical and Computer Engineering: Faculty Publications

This paper investigates the performance of two candidates for software radio WLAN, reconfigurable OFDM modulation and antenna diversity, in an indoor environment. The scenario considered is a 20m × 10m × 3m room with two base units and one mobile unit. The two base units use omnidirectional antennas to transmit and the mobile unit uses either a single antenna with equalizer, a fixed beamformer with equalizer, or an adaptive beamformer with equalizer to receive. The modulation constellation of the data is QPSK and 16-QAM. The response of the channel at the mobile unit is simulated using a three-dimensional indoor WLAN …


Preconditioning Of Primary Human Endothelial Cells With Inflammatory Mediators Alters The “Set Point” Of The Cell, Youichiro Wada, Hasan H. Otu, Shengqian Wu, Md. Ruhul Abid, Hitomi Okada, Towia Libermann, Tatsuhiko Kodama, Shu-Ching Shih, Takashi Minami, William C. Aird Jan 2005

Preconditioning Of Primary Human Endothelial Cells With Inflammatory Mediators Alters The “Set Point” Of The Cell, Youichiro Wada, Hasan H. Otu, Shengqian Wu, Md. Ruhul Abid, Hitomi Okada, Towia Libermann, Tatsuhiko Kodama, Shu-Ching Shih, Takashi Minami, William C. Aird

Department of Electrical and Computer Engineering: Faculty Publications

Endothelial cells are highly sensitive to changes in the extracellular milieu. Sepsis results in activation of inflammatory and coagulation pathways. We hypothesized that sepsis-associated mediators may alter the response capacity (so-called “set point”) of endothelial cells. Human umbilical vein endothelial cells (HUVEC) were preincubated in the presence or absence of tumor necrosis factor (TNF)-α, lipopolysaccharide (LPS), hypoxia, hyperthermia, and/or high glucose; treated with or without thrombin for 4 h; and then processed for RNase protection assays of selected activation markers. Priming with TNF-α and LPS significantly inhibited thrombin-mediated induction of vascular cell adhesion molecule-1, intercellular adhesion molecule-1, tissue factor, and …


A Novel Role For Gadd45Β As A Mediator Of Mmp-13 Gene Expression During Chondrocyte Terminal Differentiation, Kosei Ijiri, Luiz F. Zerbini, Haibing Peng, Ricardo G. Correa, Binfeng Lu, Nicole Walsh, Yani Zhao, Noboru Taniguchi, Xu-Ling Huang, Hasan H. Otu, Hong Wang, Jian Fei Wang, Setsuro Komiya, Patricia Ducy, Mahboob U. Rahman, Richard A. Flavell, Ellen M. Gravallese, Peter Oettgen, Towia A. Libermann, Mary B. Goldring Jan 2005

A Novel Role For Gadd45Β As A Mediator Of Mmp-13 Gene Expression During Chondrocyte Terminal Differentiation, Kosei Ijiri, Luiz F. Zerbini, Haibing Peng, Ricardo G. Correa, Binfeng Lu, Nicole Walsh, Yani Zhao, Noboru Taniguchi, Xu-Ling Huang, Hasan H. Otu, Hong Wang, Jian Fei Wang, Setsuro Komiya, Patricia Ducy, Mahboob U. Rahman, Richard A. Flavell, Ellen M. Gravallese, Peter Oettgen, Towia A. Libermann, Mary B. Goldring

Department of Electrical and Computer Engineering: Faculty Publications

The growth arrest and DNA damage-inducible 45β (GADD45β) gene product has been implicated in the stress response, cell cycle arrest, and apoptosis. Here we demonstrated the unexpected expression of GADD45β in the embryonic growth plate and uncovered its novel role as an essential mediator of matrix metalloproteinase-13 (MMP-13) expression during terminal chondrocyte differentiation. We identified GADD45β as a prominent early response gene induced by bone morphogenetic protein-2 (BMP-2) through a Smad1/Runx2-dependent pathway. Because this pathway is involved in skeletal development, we examined mouse embryonic growth plates, and we observed expression of Gadd45β mRNA coincident with Runx2 protein …


Range Imaging Observations Of Pmse Using The Eiscat Vhf Radar: Phase Calibration And First Results, J. R. Fernandez, R. D. Palmer, P. B. Chilson, I. Haggstrom, M. T. Rietveld Jan 2005

Range Imaging Observations Of Pmse Using The Eiscat Vhf Radar: Phase Calibration And First Results, J. R. Fernandez, R. D. Palmer, P. B. Chilson, I. Haggstrom, M. T. Rietveld

Department of Electrical and Computer Engineering: Faculty Publications

A novel phase calibration technique for use with the multiple-frequency Range IMaging (RIM) technique is introduced based on genetic algorithms. The method is used on data collected with the European Incoherent SCATter (EISCAT) VHF radar during a 2002 experiment with the goal of characterizing the vertical structure of Polar Mesosphere Summer Echoes (PMSE) over northern Norway. For typical Doppler measurements, the initial phases of the transmitter and receiver are not required to be the same. The EISCAT receiver systems exploit this fact, allowing a multistatic configuration. However, the RIM method relies on the small phase differences between closely spaced frequencies. …


Phased-Array Design For Biological Clutter Rejection: Simulation And Experimental Validation, B.L. Cheong, Michael Hoffman, R.D. Palmer, Stephen J. Frasier, F.J. Lopez-Dekker Jan 2005

Phased-Array Design For Biological Clutter Rejection: Simulation And Experimental Validation, B.L. Cheong, Michael Hoffman, R.D. Palmer, Stephen J. Frasier, F.J. Lopez-Dekker

Department of Electrical and Computer Engineering: Faculty Publications

This paper highlights recent results obtained with the Turbulent Eddy Profiler (TEP), which was devel- oped by the University of Massachusetts. This unique 915-MHz radar has up to 64 spatially separated receiving elements, each with an independent receiver. The calibrated raw data provided by this array could be processed using sophisticated imaging algorithms to resolve the horizontal structures within each range gate. After collecting all of the closely spaced horizontal slices, the TEP radar can produce three- dimensional images of echo power, radial velocity, and spectral width. From the radial velocity measure- ments, it is possible to estimate the three-dimensional …


Observations Of The Small-Scale Variability Of Precipitation Using An Imaging Radar, Robert D. Palmer, Boon Leng Cheong, Michael Hoffman, Stephen J. Frasier, F.J. Lopez-Dekker Jan 2005

Observations Of The Small-Scale Variability Of Precipitation Using An Imaging Radar, Robert D. Palmer, Boon Leng Cheong, Michael Hoffman, Stephen J. Frasier, F.J. Lopez-Dekker

Department of Electrical and Computer Engineering: Faculty Publications

For many years, spatial and temporal inhomogeneities in precipitation fields have been studied using scanning radars, cloud radars, and disdrometers, for example. Each measurement technique has its own advantages and disadvantages. Conventional profiling radars point vertically and collect data while the atmosphere advects across the field of view. Invoking Taylor’s frozen turbulence hypothesis, it is possible to construct time-history data, which are used to study the structure and dynamics of the atmosphere. In the present work, coherent radar imaging is used to estimate the true three-dimensional structure of the atmosphere within the field of view of the radar. The 915-MHz …