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201 Stringfellow, Gerald B.Effects of low surfactant Sb coverage on Zn and C incorporation in GaPThe use of surfactants during the vapor phase growth of III-V materials to control fundamental characteristics of epitaxial layers is becoming increasingly important. We have investigated the remarkable effects of Sb, from triethylantimony (TESb) Pyrolysis, on the Zn doping during the organometallic...Surfactants; Organometallic vapor phase epitaxy; Gallium phosphide2007
202 Stringfellow, Gerald B.Effects of substrate misorientation and growth rate on ordering in GaInPEpitaxial layers of Ga,Tn,_,P with 1=0.52 have been grown by-organometallic vapor-phase apitaxy on GaAs substrates misoriented from the (001) plane in the [ 1 IO] direction by angles 6,) of O", 3", 6", and 9". For each substrate orientation growth rates rg of 1, 2, and 4 pm/h have been used. The ...Transmission electron diffraction; Dark-field imaging; Photoluminescence1994
203 Stringfellow, Gerald B.Effects of surfactants Sb and Bi on the incorporation of zinc and carbon in III/V materials grown by organometallic vapor-phase epitaxyThe incorporation of both dopants and background impurities during the organometallic vapor phase epitaxial _x0002_OMVPE_x0003_ growth of GaAs, GaInP, and GaP has been significantly altered by the use of the surfactants Sb and Bi. Sb and Bi are isoelectronic with the group V host elements, and so ...Physical and chemical processes; Surfactants isoelectronic; Electrochemical C-V profilometry2006
204 Stringfellow, Gerald B.Effects of V/III ratio on ordering and antiphase boundaries in GaInP layersTransmission electron microscope (TEM) and transmission electron diffraction (TED) studies have been performed to investigate the effects of V/III ratio on ordering and antiphase boundaries (APBs) in organometallic vapor phase epitaxial Ga0.5In0.5P layers grown onto (001) GaAs vicinal substrates ...Antiphase boundaries; APB; Heterostructures; Organometallics1997
205 Stringfellow, Gerald B.Effects of V/III ratio on ordering in GaInP: atomic scale mechanismsGa0.5In0.5P layers have been grown by organometallic vapor-phase epitaxy using various values of input V/III ratio for two phosphorus precursors, phosphine, the conventional precursor, and tertiarybutylphosphine (TBP), a newly developed, less-hazardous precursor. For growth on nominally (001) GaAs s...Photoabsorption spectroscopy; Transmission electron diffraction; Phosphorus precursor1996-05-01
206 Hendee, Shonn P.; Faour, Fouad A.; Christensen, Douglas A.; Patrick, Baharah; Durney, Carl H.; Blumenthal, Donald K.Effects of weak extremely low frequency magnetic fields on calcium/calmodulin interactions.Mechanisms by which weak electromagnetic fields may affect biological systems are of current interest because of their potential health effects. Lednev has proposed an ion parametric resonance hypothesis (Lednev, 1991, Bioelectromagnetics, 12:71-75), which predicts that when the ac, frequency of a c...Electromagnetic Fields; Calcium-binding Proteins; Lednev's Theory1996-06
207 Khan, Faisal HabibEfficiency characterization and impedance modeling of a multilevel switched-capacitor converter using pulse dropping switching schemeApulse dropping switching technique (PDT) has been presented in this paper to accomplish variable conversion ratio (CR) in a multilevel modular capacitor-clamped dc-dc converter in the step-up conversion mode. The switching pattern is generated by comparing a triangular wave with a rectangular wave,...2014-01-01
208 Mathews, V. JohnEfficient block-adaptive parallel-cascade quadratic filtersAbstract-This brief presents computationally efficient block-adaptive algorithms for quadratic filters employing parallel-cascade realizations of the system model. Parallel-cascade realizations implement higher order Volterra systems using a parallel connection of multiplicative combinations of lowe...1999
209 Myers, Chris J.Efficient exact two-level hazard-free logic minimizationAbstract This paper presents a new approach to two-level hazard-free sum-of-products logic minimization. No currently available minimizers for single-output literal-exact two-level hazard-free logic minimization can handle large circuits without synthesis times ranging up over thousands of seconds....2001
210 Mathews, V. JohnEfficient FIR adaptive filter using DPCM and the sign algorithmThis correspondence introduces an adaptive filter structure that requires zero multiplications for its implementation. The primary input signal is quantized using DPCM, and the DPCM outputs are processed by a conventional adaptive filter. The filter coefficients are updated using the sign algorithm....1989
211 Simpson, Jamesina J.Efficient modeling of impulsive ELF antipodal propagation about the earth sphere using an optimized two-dimensional geodesic FDTD gridThis letter reports the initial application of a geodesic finite-difference time-domain (FDTD) grid to model impulsive extremely low frequency electromagnetic wave propagation about the Earth sphere. The two-dimensional transverse-magnetic grid is comprised entirely of hexagonal cells, except for a ...2004-01-01
212 Myers, Chris J.Efficient timing analysis algorithms for timed state space exploration*Abstract This paper presents new timing analysis algorithms for efficient state space exploration during timed circuit synthesis. Timed circuits are a class of asynchronous circuits that incorporate explicit timing information in the specification which is used throughout the synthesis procedure t...1997
213 Myers, Chris J.Efficient verification of hazard-freedom in gate-level timed asynchronous circuitsAbstract-This paper presents an efficient method for verifying hazard-freedom in gate-level timed asynchronous circuits. Timed circuits are a class of asynchronous circuits that are optimized using explicit timing information. In asynchronous circuits, correct operation requires that there are no ha...2007
214 Mastrangelo, Carlos H.Electrical characterization of 26 × 26 ground reaction sensor array interfaced with two parallel electronic detection channelsThis paper presents the electrical characterization results of a 26 x 26 high-density ground reaction sensor array (HD-GRSA) interfaced with two parallel electronic detection channels. The system was developed for improving inertial measurement unit (IMU) positioning accuracy. The HD-GRSA is compose...2013-01-01
215 Furse, Cynthia M.; Lazzi, Gianluca; Gandhi, Om P.Electrical energy absorption in the human head from a cellular telephoneThe antenna of a cellular telephone in close proximity to the human head for a variety of time periods raises questions. This research uses finite-difference time-domain (FDTD) method to calculate the power deposition from a cellular telephone on a high-resolution model of a human head as measured b...Finite-difference time-domain method; FDTD; Power deposition; Human head model; Electrical energy absorption; Specific absorption rate1996
216 Stringfellow, Gerald B.Electrical properties of nitrogen doped GaPThe electrical properties namely, electron concentration and mobility, have been investigated in the temperature range from 53 to 400 K for undoped and nitrogen-doped VPE GaP.Electron concentration; Ionization energy; Electron mobility1975
217 Simpson, Jamesina J.Electrokinetic effect of the loma prieta earthquake calculated by an entire-earth FDTD solution of Maxwell's equationsWe report what we believe to be the first three-dimensional computational solution of the full-vector Maxwell's equations for hypothesized pre-seismic electromagnetic phenomena propagated within the entire Earth-ionosphere cavity. Periodic boundary conditions are used in conjunction with a variable-...2005-01-01
218 Furse, Cynthia M.; Gandhi, Om P.; Lazzi, GianlucaElectromagnetic absorption in the human head and neck for mobile telephones at 835 and 1900 MHzWe have used the finite-difference time-domain method and a new millimeter-resolution anatomically based model of the human to study electromagnetic energy coupled to the head due to mobile telephones at 835 and 1900 MHz. Assuming reduced dimensions characteristic of today's mobile telephones, we h...Electromagnetic absorption; FDTD; Finite-difference time-domain; Specific absorption rates; SAR1996-01-01
219 Furse, Cynthia M.Electromagnetics education in North AmericaThis paper starts with a description of the activities of the education committees of the IEEE Antennas and Propagation, Microwave Theory and Techniques, and Electromagnetic Compatibility societies and the United States National Committee of the International Union of Radio Science (USNC/URSI).We t...2005
220 Stringfellow, Gerald B.Electron mobility in AlxGa1-xAshe electron mobility in AlxGa1-xAs grown by several techniques has been studied to determine whether VPE layers are more highly compensated than comparable LPE layers. The techniques used to grow layers included (1) organometallic VPE using Al(CH3)3, AsH3, and Ga(C2H5)3 or Ga(CH3)3, (2) ''hybrid'' o...Alloys; Organometallics1979-06
221 Stringfellow, Gerald B.Electron mobility in compensated GaAs and AlGaAsThe dependence of electron mobility on temperature in GaAs and Al Ga As indicates that for cimpensated material a term having causes a significant reduction in the mobility measured at high temperatures. The magnitude of the term in mobility, denoted is found to be linearly proportional to the compe...Unspecified mobility; Reduced mobility; Space charge regions1980
222 Simpson, Jamesina J.ELF radar system proposed for localized D-region ionospheric anomaliesThis letter proposes a novel extremely low frequency (ELF) radar for localized D-region (altitude < 95 km) ionospheric anomalies that have been generated by natural geophysical processes. The proposed system would use the former U.S. Navy Wisconsin Transmitting Facility as a distant well-characteriz...2006-01-01
223 Furse, Cynthia M.Enabling wireless communication in aircraft using multipe antenna systemsSensor technology is advancing to provide the robust, miniaturized sensors needed for aircraft prognostics health management (PHM). Aircraft maintainers would like to add numerous pressure, temperature, vibration, fuel quantity, moisture/chemical sensors, but a major challenge of retrofitting old ai...2009-01-01
224 Stevens, KennethEnergy and performance models for clocked and asynchronous communicationParameterized first-order models for throughput, energy, and bandwidth are presented in this paper. Models are developed for many common pipeline methodologies, including clocked flopped, clocked time-borrowing latch protocols, asynchronous two-cycle, four-cycle, delay-insensitive, and source synch...2003
225 Stevens, KennethEnergy and performance models for synchronous and asynchronous communicationCommunication costs, which have the potential to throttle design performance as scaling continues, are mathematically modeled and compared for various pipeline methodologies. First-order models are created for common pipeline protocols, including clocked flopped, clocked time-borrowing latch, async...2010
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