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University of South Carolina

Series

2000

Articles 1 - 30 of 35

Full-Text Articles in Engineering

High-Quality P-N Junctions With Quaternary Alingan/Ingan Quantum Wells, A. Chitnis, A. Kumar, M. Shatalov, V. Adivarahan, A. Lunev, J. W. Yang, Grigory Simin, M. Asif Khan, R. Gaska, M. Shur Dec 2000

High-Quality P-N Junctions With Quaternary Alingan/Ingan Quantum Wells, A. Chitnis, A. Kumar, M. Shatalov, V. Adivarahan, A. Lunev, J. W. Yang, Grigory Simin, M. Asif Khan, R. Gaska, M. Shur

Faculty Publications

We report on quaternary AlInGaN/InGaN multiple quantum well(MQW)light emitting diode structures grown on sapphire substrates. The structures demonstrate high quality of the p–njunctions with quaternary MQW. At low forward bias (below 2 V), the temperature dependent of current–voltage characteristics are exponential with the ideality factor of 2.28, which is in a good agreement with the model of the injected carrier recombination in the space charge region. This ideality factor value is approximately three times lower than for conventional GaN/InGaN light emitting diodes(LEDs). The obtained data indicate the recombination in p–njunction space charge region to be responsible for a current transport …

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Effect Of Gate Leakage Current On Noise Properties Of Algan/Gan Field Effect Transistors, S. L. Rumyantsev, N. Pala, M. S. Shur, R. Gaska, M. E. Levinshtein, M. Asif Khan, Grigory Simin, X. Hu, J. Yang Dec 2000

Effect Of Gate Leakage Current On Noise Properties Of Algan/Gan Field Effect Transistors, S. L. Rumyantsev, N. Pala, M. S. Shur, R. Gaska, M. E. Levinshtein, M. Asif Khan, Grigory Simin, X. Hu, J. Yang

Faculty Publications

The effect of the gate leakage current fluctuations on noiseproperties of AlGaN/GaN heterostructurefield effect transistors(HFETs) has been studied in conventional HFET structures and in AlGaN/GaN metal-oxide-semiconductorheterostructurefield effect transistors (MOS-HFETs). The comparison of the noiseproperties of conventional AlGaN/GaN HFETs and AlGaN/GaN MOS-HFETs fabricated on the same wafer, allowed us to estimate the contribution of the gate currentnoise to the HFET’s output noise. The effect of the gate current fluctuations on output noiseproperties of HFETs depends on the level of noise in the AlGaN/GaN HFETs. For the transistors with a relatively high magnitude of the Hooge parameter α∼10−3, even a …

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High Performance Micropane Electron Beam Window, Roger A. Dougal, Shengyi Liu Nov 2000

High Performance Micropane Electron Beam Window, Roger A. Dougal, Shengyi Liu

Faculty Publications

A silicon disk etched so that it contains a multitude of microscopic and thin window panes (micropanes) can potentially transmit a larger average electron beam current density and absorb a smaller fraction of the beam energy than a common metal foil window. The enhanced performance is achieved by a combination of decreased power loss due to the extremely small window thickness (~1 μm), and increased conductive cooling due to the small diameter (~50 μm) of the micropanes and the large cross section of the honeycomb structure that supports the micropanes. Beam current densities up to 34 A/cm2 are permitted within …

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Hop Integrity In Computer Networks, Mohamed G. Gouda, E.N. Elnozahy, Chin-Tser Huang, Tommy M. Mcguire Nov 2000

Hop Integrity In Computer Networks, Mohamed G. Gouda, E.N. Elnozahy, Chin-Tser Huang, Tommy M. Mcguire

Faculty Publications

A computer network is said to provide hop integrity iff when any router p in the network receives a message m supposedly from an adjacent router q, then p can check that m was indeed sent by q, was not modified after it was sent, and was not a replay of an old message sent from q to p. We describe three protocols that can be added to the routers in a computer network so that the network can provide hop integrity. These three protocols are a secret exchange protocol, a weak integrity protocol, and a strong integrity protocol. All …

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Enhanced Luminescence In Ingan Multiple Quantum Wells With Quaternary Alingan Barriers, Jianping Zhang, J. Yang, Grigory Simin, M. Shatalov, M. Asif Khan, M. S. Shur, R. Gaska Oct 2000

Enhanced Luminescence In Ingan Multiple Quantum Wells With Quaternary Alingan Barriers, Jianping Zhang, J. Yang, Grigory Simin, M. Shatalov, M. Asif Khan, M. S. Shur, R. Gaska

Faculty Publications

We report on the comparative photoluminescence studies of AlGaN/GaN, GaN/InGaN, and AlInGaN/InGaN multiple quantum well(MQW) structures. The study clearly shows the improvement in materials quality with the introduction of indium. Our results point out the localized state emission mechanism for GaN/InGaN structures and the quantum well emission mechanism for AlInGaN/InGaN structures. The introduction of indium is the dominant factor responsible for the observed differences in the photoluminescence spectra of these MQW structures.

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High Electron Mobility In Algan/Gan Heterostructures Grown On Bulk Gan Substrates, E. Frayssinet, W. Knap, P. Lorenzini, N. Grandjean, J. Massies, C. Skierbiszewski, T. Suski, I. Grzegory, S. Porowski, Grigory Simin, X. Hu, M. Asif Khan, M. S. Shur, R. Gaska, D. Maude Oct 2000

High Electron Mobility In Algan/Gan Heterostructures Grown On Bulk Gan Substrates, E. Frayssinet, W. Knap, P. Lorenzini, N. Grandjean, J. Massies, C. Skierbiszewski, T. Suski, I. Grzegory, S. Porowski, Grigory Simin, X. Hu, M. Asif Khan, M. S. Shur, R. Gaska, D. Maude

Faculty Publications

Dislocation-free high-quality AlGaN/GaN heterostructures have been grown by molecular-beam epitaxy on semi-insulating bulk GaN substrates. Hall measurements performed in the 300 K–50 mK range show a low-temperature electron mobility exceeding 60 000 cm2/V s for an electron sheet density of 2.4×1012 cm−2. Magnetotransport experiments performed up to 15 T exhibit well-defined quantum Hall-effect features. The structures corresponding to the cyclotron and spin splitting were clearly resolved. From an analysis of the Shubnikov de Hass oscillations and the low-temperature mobility we found the quantum and transport scattering times to be 0.4 and 8.2 ps, respectively. The …

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Preparation Of Mesoporous Sno2-Sio2 Composite As Electrodes For Lithium Batteries, Fanglin Chen, Zhong Shi, Meilin Liu Oct 2000

Preparation Of Mesoporous Sno2-Sio2 Composite As Electrodes For Lithium Batteries, Fanglin Chen, Zhong Shi, Meilin Liu

Faculty Publications

Mesoporous SnO2–SiO2 composite stable up to 600 °C with a BET surface area of 350 m2 g-1 and an average pore size of 3.4 nm is successfully prepared, which exhibits promising cycling properties as anodes for lithium batteries

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Preparation Of Mesoporous Yttria-Stabilized Zirconia (Ysz) And Ysz-Nio Using A Triblock Copolymer As Surfactant, Fanglin Chen, Meilin Liu Oct 2000

Preparation Of Mesoporous Yttria-Stabilized Zirconia (Ysz) And Ysz-Nio Using A Triblock Copolymer As Surfactant, Fanglin Chen, Meilin Liu

Faculty Publications

Mesoporous yttria-stabilized zirconia (YSZ) and YSZ-NiO have been prepared for the first time using Pluronic P103 as a structure-directing agent and inorganic chlorides as precursors in a nonaqueous medium. After being fired at 500°C for 2 h, mesostructured YSZ has a BET surface area of about 146 m2 g-1, with an average pore size of 3.8 nm, while mesostructured YSZ-NiO has a BET surface area of about 108 m2 g-1, with an average pore size of 4.5 nm.

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Optical Bandgap Formation In Alingan Alloys, G. Tamulaitis, K. Kazlauskas, S. Juršėnas, A. Žukauskas, M. A. Khan, J. W. Yang, J. Zhang, Grigory Simin, M. S. Shur, R. Gaska Oct 2000

Optical Bandgap Formation In Alingan Alloys, G. Tamulaitis, K. Kazlauskas, S. Juršėnas, A. Žukauskas, M. A. Khan, J. W. Yang, J. Zhang, Grigory Simin, M. S. Shur, R. Gaska

Faculty Publications

We report on the spectral dynamics of the reflectivity, site-selectively excited photoluminescence,photoluminescence excitation, and time-resolved luminescence in quaternary AlInGaN epitaxial layers grown on GaN templates. The incorporation of a few percents of In into AlGaN causes significant smoothening of the band-bottom potential profile in AlInGaN layers owing to improved crystal quality. An abrupt optical bandgap indicates that a nearly lattice-matched AlInGaN/GaN heterostructure with large energy band offsets can be grown for high-efficiency light-emitting devices.

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Algan/Gan Metal-Oxide-Semiconductor Heterostructure Field-Effect Transistors On Sic Substrates, M. Asif Khan, X. Hu, A. Tarakji, Grigory Simin, J. Yang, R. Gaska, M. S. Shur Aug 2000

Algan/Gan Metal-Oxide-Semiconductor Heterostructure Field-Effect Transistors On Sic Substrates, M. Asif Khan, X. Hu, A. Tarakji, Grigory Simin, J. Yang, R. Gaska, M. S. Shur

Faculty Publications

We report on AlGaN/GaN metal–oxide–semiconductor heterostructurefield-effect transistors (MOS-HFETs) grown over insulating 4H–SiC substrates. We demonstrate that the dc and microwave performance of the MOS-HFETs is superior to that of conventional AlGaN/GaN HFETs, which points to the high quality of SiO2/AlGaNheterointerface. The MOS-HFETs could operate at positive gate biases as high as +10 V that doubles the channel current as compared to conventional AlGaN/GaN HFETs of a similar design. The gate leakage current was more than six orders of magnitude smaller than that for the conventional AlGaN/GaN HFETs. The MOS-HFETs exhibited stable operation at elevated temperatures up to 300 …

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Sio2-Passivated Lateral-Geometry Gan Transparent Schottky-Barrier Detectors, V. Adivarahan, Grigory Simin, J. W. Yang, A. Lunev, M. Asif Khan, M. Pala, M. Shur, R. Gaska Aug 2000

Sio2-Passivated Lateral-Geometry Gan Transparent Schottky-Barrier Detectors, V. Adivarahan, Grigory Simin, J. W. Yang, A. Lunev, M. Asif Khan, M. Pala, M. Shur, R. Gaska

Faculty Publications

We report on a transparent Schottky-barrierultraviolet detector on GaN layers over sapphire substrates. Using SiO2 surface passivation, reverse leakage currents were reduced to a value as low as 1 pA at 5 V reverse bias for 200 μm diameter device. The device exhibits a high internal gain, about 50, at low forward biases. The response time (about 15 ns) is RC limited, even in the internal gain regime. A record low level of the noise spectral density, 5×10−23 A2/Hz, was measured at 10 Hz. We attribute this low noise level to the reduced reverse leakage current.

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Gan-Algan Heterostructure Field-Effect Transistors Over Bulk Gan Substrates, M. Asif Khan, J. W. Yang, W. Knap, E. Frayssinet, X. Hu, Grigory Simin, P. Prystawko, M. Leszczynski, I. Grzegory, S. Porowski, R. Gaska, M. S. Shur, B. Beaumont, M. Teisseire, G. Neu Jun 2000

Gan-Algan Heterostructure Field-Effect Transistors Over Bulk Gan Substrates, M. Asif Khan, J. W. Yang, W. Knap, E. Frayssinet, X. Hu, Grigory Simin, P. Prystawko, M. Leszczynski, I. Grzegory, S. Porowski, R. Gaska, M. S. Shur, B. Beaumont, M. Teisseire, G. Neu

Faculty Publications

We report on AlGaN/GaN heterostructures and heterostructurefield-effect transistors(HFETs) fabricated on high-pressure-grown bulk GaN substrates. The 2delectron gas channel exhibits excellent electronic properties with room-temperature electron Hall mobility as high as μ=1650 cm2/V s combined with a very large electron sheet density ns≈1.4×1013 cm−2.The HFET devices demonstrated better linearity of transconductance and low gate leakage, especially at elevated temperatures. We also present the comparative study of high-current AlGaN/GaN HFETs(nsμ>2×1016 V−1 s−1) grown on bulk GaN, sapphire, and SiC substrates under the same conditions. We demonstrate that in …

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Accumulation Hole Layer In P-Gan/Algan Heterostructures, M. S. Shur, A. D. Bykhovski, R. Gaska, J. W. Yang, Grigory Simin, M. A. Khan May 2000

Accumulation Hole Layer In P-Gan/Algan Heterostructures, M. S. Shur, A. D. Bykhovski, R. Gaska, J. W. Yang, Grigory Simin, M. A. Khan

Faculty Publications

We present the results on piezoelectric and pyroelectricdoping in AlGaN-on-GaN and GaN-on-AlGaN heterostructures and demonstrate p-GaN/AlGaN structures with accumulation hole layer. Our results indicate that polarization charge can induce up to 5×1013 cm−2 holes at the AlGaN/GaN heterointerfaces. We show that the transition from three-dimensional (3D) to two-dimensional (2D) hole gas can be only achieved for hole sheet densities on the order of 1013 cm−2 or higher. At lower densities, only 3D-hole accumulation layer may exist. These results suggest that a piezoelectrically induced 2D-hole gas can be used for the reduction of the base spreading resistance …

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3d Outside Cell Interference Factor For An Air-Ground Cdma ‘Cellular’ System, David W. Matolak May 2000

3d Outside Cell Interference Factor For An Air-Ground Cdma ‘Cellular’ System, David W. Matolak

Faculty Publications

We compute the outside-cell interference factor of a code-division multiple-access (CDMA) system for a three-dimensional (3-D) air-to-ground (AG) "cellular-like" network consisting of a set of uniformly distributed ground base stations and airborne mobile users. The CDMA capacity is roughly inversely proportional to the outside-cell interference factor. It is shown that for the nearly free-space propagation environment of these systems, the outside-cell interference factor can be larger than that for terrestrial propagation models (as expected) and depends approximately logarithmically upon both the cell height and cell radius.

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Lattice And Energy Band Engineering In Alingan/Ga Heterostructures, M. Asif Khan, J. W. Yang, Grigory Simin, R. Gaska, M. S. Shur, Hans-Conrad Zur Loye, G. Tamulaitis, A. Zukauskas, David J. Smith, D. Chandrasekhar, R. Bicknell-Tassius Feb 2000

Lattice And Energy Band Engineering In Alingan/Ga Heterostructures, M. Asif Khan, J. W. Yang, Grigory Simin, R. Gaska, M. S. Shur, Hans-Conrad Zur Loye, G. Tamulaitis, A. Zukauskas, David J. Smith, D. Chandrasekhar, R. Bicknell-Tassius

Faculty Publications

We report on structural, optical, and electrical properties of AlxInyGa1−x−yNGaNheterostructures grown on sapphire and 6H–SiC substrates. Our results demonstrate that incorporation of In reduces the lattice mismatch, Δa, between AlInGaN and GaN, and that an In to Al ratio of close to 1:5 results in nearly strain-free heterostructures. The observed reduction in band gap,ΔEg, determined from photoluminescence measurements, is more than 1.5 times higher than estimated from the linear dependencies of Δa and ΔEg on the In molar fraction. The incorporation of In and resulting changes in the built-in strain in …

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Selective Area Deposited Blue Gan-Ingan Multiple-Quantum Well Light Emitting Diodes Over Silicon Substrates, J. W. Yang, A. Lunev, Grigory Simin, A. Chitnis, M. Shatalov, M. Asif Khan, Joseph E. Van Nostrand, R. Gaska Jan 2000

Selective Area Deposited Blue Gan-Ingan Multiple-Quantum Well Light Emitting Diodes Over Silicon Substrates, J. W. Yang, A. Lunev, Grigory Simin, A. Chitnis, M. Shatalov, M. Asif Khan, Joseph E. Van Nostrand, R. Gaska

Faculty Publications

We report on fabrication and characterization of blue GaN–InGaN multi-quantum well (MQW)light-emitting diodes(LEDs) over (111) silicon substrates. Device epilayers were fabricated using unique combination of molecular beam epitaxy and low-pressure metalorganic chemical vapor depositiongrowth procedure in selective areas defined by openings in a SiO2mask over the substrates. This selective area deposition procedure in principle can produce multicolor devices using a very simple fabrication procedure. The LEDs had a peak emission wavelength of 465 nm with a full width at half maximum of 40 nm. We also present the spectral emission data with the diodes operating up to 250 …

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Studies On The Capacitance Of Nickel Oxide Films: Effect Of Heating Temperature And Electrolyte Concentration, Venkat Srinivasan, John W. Weidner Jan 2000

Studies On The Capacitance Of Nickel Oxide Films: Effect Of Heating Temperature And Electrolyte Concentration, Venkat Srinivasan, John W. Weidner

Faculty Publications

Nickel oxide films were prepared by electrochemically precipitating the hydroxide and heating it in air to form the oxide. The resulting oxide films behave as a capacitor. The capacitance of the oxide depends on the heating temperature, showing a maximum at 300°C. The mechanism of charge storage was studied by measuring the capacitance and surface area as a function of heating temperature, and the capacitance in different electrolytes and potential windows. The charge-storage mechanism is believed to be a surface redox reaction involving adsorbed hydroxyl ions.

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Development Of A New Electrodeposition Process For Plating Of Zn-Ni-X (X = Cd, P) Alloys: I. Corrosion Characteristics Of Zn-Ni-Cd Ternary Alloys, Anand Durairajan, Bala S. Haran, Ralph E. White, Branko N. Popov Jan 2000

Development Of A New Electrodeposition Process For Plating Of Zn-Ni-X (X = Cd, P) Alloys: I. Corrosion Characteristics Of Zn-Ni-Cd Ternary Alloys, Anand Durairajan, Bala S. Haran, Ralph E. White, Branko N. Popov

Faculty Publications

A new Zn-Ni-Cd plating process was developed which offers a unique way of controlling and optimizing the Ni and Cd contents in the final deposit. Zinc-nickel-cadmium alloy was deposited from a 0.5 M NiSO4 + 0.2 M ZnSO4 bath in the presence of 0.015 M CdSO4 and 1 g/L nonyl phenyl polyethylene oxide. Using this process a Zn-Ni-Cd ternary alloy, with a higher nickel content as compared to that obtained from conventional Zn-Ni baths, was synthesized. The Zn-Ni-Cd alloy coatings deposited from an electrolyte containing 0.015 M (0.3%) CdSO4 has a Zn to Ni ratio of …

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Modeling The Effects Of Ion Association On Direct-Current Polarization Of Solid Polymer Electrolytes, Changqing Lin, Ralph E. White, Harry J. Ploehn Jan 2000

Modeling The Effects Of Ion Association On Direct-Current Polarization Of Solid Polymer Electrolytes, Changqing Lin, Ralph E. White, Harry J. Ploehn

Faculty Publications

Considerable experimental evidence indicates that ion association occurs in solid polymer electrolytes. This work provides a thorough theoretical analysis of the effect of ion association on the conductivity, general current-potential behavior, and limiting current density in a solid polymer electrolyte. The model employs dilute solution theory to describe the fluxes of cations, anions, and ion pairs in a motionless continuum but neglects higher order association. The predictions of the model highlight the effects of the relative diffusion coefficients and dimensionless association constant on concentration distributions of simple ions and ion pairs, the limiting current density, and the potential drop required …

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Ni-Composite Microencapsulated Graphite As The Negative Electrode In Lithium-Ion Batteries Ii: Electrochemical Impedance And Self-Discharge Studies, P. Yu, James A. Ritter, Ralph E. White, Branko N. Popov Jan 2000

Ni-Composite Microencapsulated Graphite As The Negative Electrode In Lithium-Ion Batteries Ii: Electrochemical Impedance And Self-Discharge Studies, P. Yu, James A. Ritter, Ralph E. White, Branko N. Popov

Faculty Publications

Electrochemical impedance and self-discharge studies were carried out to investigate lithium intercalation into bare and Ni-coated KS10 graphite. Values of the charge-transfer resistances, exchange current densities, surface film resistances, and lithium-ion diffusion coefficients as functions of the state of charge (SOC) all favored the 10 wt % Ni composite KS10 graphite over bare KS10 graphite when these materials were used as the negative electrode in a Li-ion cell with mixed organic electrolyte. The charge-transfer resistances were always lower and gave rise to between 26 and 27% larger exchange current densities, which increased from 137 to 614 mA/g as the SOC …

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Modeling Lithium Intercalation Of A Single Spinel Particle Under Potentiodynamic Control, Dong Zhang, Branko N. Popov, Ralph E. White Jan 2000

Modeling Lithium Intercalation Of A Single Spinel Particle Under Potentiodynamic Control, Dong Zhang, Branko N. Popov, Ralph E. White

Faculty Publications

A mathematical model is presented for the lithium intercalation of a single spinel particle as a microelectrode under the stimulus of a cyclic linear potential sweep. The model includes both lithium diffusion within the particle and kinetics at the particle/electrolyte interface. The model is used to predict that peak current densities depend linearly on the scan rate to a certain power with a constant term, which is different from the predicted peak current density for a conventional redox system.

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Self‐Discharge Model Of A Nickel‐Hydrogen Cell, B. Wu, Ralph E. White Jan 2000

Self‐Discharge Model Of A Nickel‐Hydrogen Cell, B. Wu, Ralph E. White

Faculty Publications

No abstract provided.

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A Semianalytical Method For Predicting Primary And Secondary Current Density Distributions: Linear And Nonlinear Boundary Conditions, Dhanwa Thirumalai, Ralph E. White Jan 2000

A Semianalytical Method For Predicting Primary And Secondary Current Density Distributions: Linear And Nonlinear Boundary Conditions, Dhanwa Thirumalai, Ralph E. White

Faculty Publications

No abstract provided.

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Development Of A New Electrodeposition Process For Plating Of Zn‐Ni‐X (X = Cd, P) Alloys: I. Corrosion Characteristics Of Zn‐Ni‐Cd Ternary Alloys, Anand Durairajan, Bala S. Haran, Ralph E. White, Branko Popov Jan 2000

Development Of A New Electrodeposition Process For Plating Of Zn‐Ni‐X (X = Cd, P) Alloys: I. Corrosion Characteristics Of Zn‐Ni‐Cd Ternary Alloys, Anand Durairajan, Bala S. Haran, Ralph E. White, Branko Popov

Faculty Publications

No abstract provided.

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Modeling The Effect Of Plasticizer On The Viscoelastic Response Of Crosslinked Polymers Using The Tube-Junction Model, P. P. Simon, Harry J. Ploehn Jan 2000

Modeling The Effect Of Plasticizer On The Viscoelastic Response Of Crosslinked Polymers Using The Tube-Junction Model, P. P. Simon, Harry J. Ploehn

Faculty Publications

Plasticizers modify the mechanical properties of polymericmaterials. The effects of plasticizers on glass transition temperatures can be most clearly observed in isochronal temperature sweep profiles of viscoelastic dynamic moduli. However, no simple mathematical models of plasticization are available to those who wish to design and employ plasticized materials in specific applications. We extend a phenomenological, molecular-level model (known as the tube–junction model) for crosslinked polymers to describe the effect of plasticizers on dynamic moduli. We show that the increase in free volume fraction due to the presence of the plasticizer can account for the shift in the glass transition in …

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An Agent-Based Global Economy, Michael N. Huhns Jan 2000

An Agent-Based Global Economy, Michael N. Huhns

Faculty Publications

Many people are buying music CDs over the Web, but with multiple retail sites offering the same CDs, how do you decide which retailer to buy from? Typically, you visit a few sites and choose the one with the lowest price. Shopbotsshopping agents that automatically search the Internet to obtain information about prices and other attributes of goods and servicesare ideal helpers for such a task.1 The better ones can visit hundreds of sites, giving price-conscious consumers a powerful tool that could work to the detriment of some retailers.

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Structural And Electrical Characterization Of A Novel Mixed Conductor: Ceo2 - Sm2O3 - Zro2 Solid Solution, W. Huang, P. Shuk, M. Greenblatt, M. Croft, Fanglin Chen, M. Liu Jan 2000

Structural And Electrical Characterization Of A Novel Mixed Conductor: Ceo2 - Sm2O3 - Zro2 Solid Solution, W. Huang, P. Shuk, M. Greenblatt, M. Croft, Fanglin Chen, M. Liu

Faculty Publications

solid solutions were synthesized for the first time by the hydrothermal method. The electrical properties of the solid solutions have been studied in air and under reducing conditions. Solid solutions with the fluorite structure were formed in all of the studied range of substitution after calcination at 1500°C. With increasing substitution up to 30 mol %, the electronic conductivity increases under a reducing atmosphere. The solid solution has good mixed electronic and ionic conductivity; the total conductivity is 0.42 S/cm at and 700°C with an estimated ionic conductivity of ca. .

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The Emergence Of Language Among Autonomous Agents, Piotr Gmytrasiewicz, Michael N. Huhns Jan 2000

The Emergence Of Language Among Autonomous Agents, Piotr Gmytrasiewicz, Michael N. Huhns

Faculty Publications

Suppose some autonomous shopbot agents had been representing us by dealing with a vendor's pricebot, and suppose they didn't share an agent communication language (ACL). What should they know at a fundamental level, what could each point to, and how could they establish a common language? Recent research at the University of Texas at Arlington has shown that agents first establish a common vocabulary, progress to a primitive language similar to human pidgin, then enrich the language's grammar to develop a creole, and eventually arrive at a full-blown ACL. During this process, the vocabulary and grammatical structures most important to …

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Sensors + Agents + Networks = Aware Agents, Michael N. Huhns, Sreenath Seshadri Jan 2000

Sensors + Agents + Networks = Aware Agents, Michael N. Huhns, Sreenath Seshadri

Faculty Publications

Software agents are being deployed in increasing numbers to help users find and manage information, particularly in open environments such as the Internet. For the most part, they operate independently and are typically designed to be aware only of their users and the environment in which they perform their tasks. Thus, they fail to take advantage of each other's abilities or results. For example, a shopping agent might periodically access several online databases to find the best price for a music CD and then purchase it if the price falls below its user's threshold. Other agents might be tracking prices …

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Agent Teams: Building And Implementing Software, Michael N. Huhns Jan 2000

Agent Teams: Building And Implementing Software, Michael N. Huhns

Faculty Publications

Agents will become fundamental building blocks for general-purpose Internet-based software. The software may not display any explicitly agent-like characteristics, but it will exhibit the benefits of tolerance to errors, ease of maintenance, adaptability to change, and speed of construction that agents provide. Moreover, an agent-based approach to software development can lead to new types of software solutions that might not otherwise be obvious. The author considers how an approach based on teams of active, cooperative, and persistent software components, that is agents, shows special promise in enabling the rapid construction of robust and reusable software.

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