A5036132274- Photonic and Optical Devices
- Parallel Computing and Optimization Techniques
- Advanced Fiber Laser Technologies
- Gyrotron and Vacuum Electronics Research
- Fish Ecology and Management Studies
- Particle accelerators and beam dynamics
- Distributed and Parallel Computing Systems
- Remote Sensing and LiDAR Applications
- Electromagnetic Launch and Propulsion Technology
- Remote Sensing in Agriculture
- Energy Harvesting in Wireless Networks
- Interconnection Networks and Systems
- Advanced Data Compression Techniques
- Advanced Data Storage Technologies
- Advanced Photonic Communication Systems
- Fish Biology and Ecology Studies
- Wireless Power Transfer Systems
- Plasma Diagnostics and Applications
- Algorithms and Data Compression
- Advanced Vision and Imaging
- Satellite Communication Systems
- Cancer Treatment and Pharmacology
- Educational Challenges and Innovations
- Advanced Image Processing Techniques
- Global Health and Surgery
BAE Systems (United States)
2023-2024
BAE Systems (Sweden)
2024
University of Maryland, College Park
2016-2023
Goddard Space Flight Center
2020
American Institute for Voice and Ear Research
2016-2017
University of California, Davis
2008
Advanced Applications (United States)
2003
University of Arizona
1992-2002
Ocean Acoustical Services and Instrumentation Systems (United States)
1994
Hanazono University
1994
The transfer of digital images between data archives and scientific workstations is likely to consume a significant amount network bandwidth in the very near future. This paper examines image problem from an end-to-end perspective, that is, it describes complete protocol takes into account both nature imagery properties underlying network. Specifically, simple algorithm for encoding packets such way receiver can recover dropped without requiring sender retransmit them. Avoiding...
Abstract Fertilization of freshwater striped bass rearing ponds with cottonseed meal or chicken manure and litter in combination liquid inorganic fertilizers zooplankton inoculation were evaluated 10 0.04-ha (0.10 acre) over a 4-week period. Chlorophyll α levels pH significantly higher, alkalinity Secchi disk visibility lower, fertilized meal. Ponds produced more crustacean than did litter. Fish survival production averaged 63% 49 kg/ha (43.7 lbs/acre) 46% 26 (23.3 Adult copepods small...
This study investigates the ability to locally ignite metallized propellants via microwave absorption. Metallized energetic composite films incorporating high mass loadings of aluminum and titanium nanoparticle fuels within a polyvinylidene fluoride (PVDF) polymer matrix were constructed by direct-write additive manufacturing (3D printing). Simulations power absorption for both Ti Al nanoparticles reveal that passivating shell composition likely plays significant role in observed ignition...
Many public fishing lakes constructed in Alabama first contained the state's native largemouth bass Micropterus salmoides, which has allozyme frequencies similar to those of pure northern subspecies, M. s. salmoides. these then were supplementally stocked with fingerlings Florida subspecies floridanus. The supplemental introductions had varying success, and 10 11 populations we examined undergone significant (P < 0.05) allele-frequency changes–representing introgression alleles-at diagnostic...
Telehealth-embedded knowledge packets in conjuction with point-of-care testing strategically placed small-world networks for regional health care delivery can provide multilingual education and intellectual connectivity at levels of sophistication appropriate the practice modern evidence-based medicine worldwide. In addition, demographic topographic integration efficient critical, emergency, disaster thereby improve public preparedness, especially underserved low-resource settings most need help.
<title>Abstract</title> Extremely high-Q microresonators provide an attractive platform for a plethora of photonic applications including optical frequency combs, high-precision metrology, telecommunication, microwave generation, narrow linewidth lasers, and stable references. Moreover, the desire compactness low power threshold nonlinear phenomena have spurred investigation into integrated scalable solutions. Historically, crystalline with Q~10^9 were one first material platforms providing...
Abstract Extremely high- Q microresonators provide an attractive platform for a plethora of photonic applications including optical frequency combs, high-precision metrology, telecommunication, microwave generation, narrow linewidth lasers, and stable references. Moreover, the desire compactness low power threshold nonlinear phenomena have spurred investigation into integrated scalable solutions. Historically, crystalline with $$\sim$$ 10 9 were one first material platforms providing...
The property inheritance network (PIN) is a dynamically controlled machine that accesses information stored in hierarchical content addressable memory. associative memory implemented using adaptive resonance circuits. These circuits are monitored by set of control neurons become active when certain system states occur and generate signals sequential search through taxonomy information. This paper reviews pertinent knowledge representation concepts summarizes the theory Carpenter Grossberg as...
The transfer of digital images between data archives and scientific workstations is likely to consume a significant amount network bandwidth in the very near future. This paper examines image problem from an end-to-end perspective, that is, it describes complete protocol takes into account both nature imagery properties underlying network. Specifically, simple algorithm for encoding packets such way receiver can recover dropped without requiring sender retransmit them. Avoiding...
The sub-mm wave region of the electromagnetic spectrum, especially span 70 GHz centered on 556.9 H2O water line, offers a rich harvest highly diagnostic volatile species that provide powerful insights into planetary body's origins, thermal history, and conditions for habitability. Previous spaceborne Heterodyne Sub-mm Wave Spectrometers (HSWS) process small fraction their capable bandwidth at given moment. design each spectrometer channel also depends priori knowledge observable spectral...
This article presents a high-rejection, thin-film high-temperature superconductor, microstrip bandstop filter to prevent local, and high-power radio-frequency interference (RFI) source from interfering with NASA Goddard Geophysical Astronomical Observatory (GGAO)’s very long baseline interferometry (VLBI) global observing system (VGOS) cryogenic receiver. has an excellent 2.7%, 50-dB-fractional-bandwidth, center stopband frequency of 9.41 GHz. It does not contain any narrow or interdigital...
Thermoreflectance Microscopy (TRM) is an optical technique for imaging the thermal profiles of photonic and electronic devices with sub-micron spatial resolutions. TRM has been applied to integrated circuits consisting many different conductor semiconductor materials. Time-Domain (TDTR) measurement techniques have polymers measure their properties (e.g. heat conductance), but there a lack data polymer-based devices. In this letter, we demonstrate can be successfully acrylate-based resin....
Data parallel languages are gaining interest as it becomes clear that they support a wider range of computation than previously believed. With improved network technology, is now feasible to build data supercomputers using traditional RISC-based workstations connected by highspeed network. The paper presents an in-depth look at the communication behavior nine C/sup */ programs (J.L. Frankel, 1991). It also compares performance these on both cluster 8 HP 720 and 32 node (128 Vector Unit)...
Development of Mobile Ionospheric Heating sources (MIHs) would allow investigators to conduct needed research at different latitudes without building permanent and costly installations. As part an Air Force Multi-University Research Initiative (MURI), the University Maryland is designing a prototype powerful Radio Frequency (RF) source utilizing Inductive Output Tube (IOT) technology operating in class-D with mod-anode controlled electron gun [1]. This was chosen because it has potential...
We report progress on the development of a high-power, high-efficiency source for moveable ionospheric heater. The is based Inductive Output Tube concept. application requires operation in 3-10 MHz range, thus opening possibility to achieve true class - D and with that high efficiency. Our designs incorporate solid-state driver, grid-less gun, tunable output circuit. Preliminary results scaled device will be presented.
Biological diversity is decreasing at an alarming rate worldwide. Improved ecosystem monitoring can help detect problems in time to intervene. Earth orbiting satellites collecting terabytes of imagery daily, support effective many habitats. Data parallelism ideal for automated image analysis algorithms, but less natural the complex spatial structure most ecosystems. This paper presents a coarse-to-fine processing framework: based on set transformations, that compact disconnected regions...
A heterogeneous network of parallel computers developed for complex distributed-processing applications is described. Network include a Connection Machine, Butterfly multiprocessor, WARP systolic array, and Symbolics several SUN workstations. An Ethernet high-bandwidth APTEC bus support data transfers. Distributed are built from individual processes executing on in the network. powerful asynchronous communication facility upon multiple computer operating systems to provide uniform message...
The effect of Si3N4 deposition conditions on the electrical properties ON dielectric films smooth and as-deposited rugged polycrystalline silicon is investigated. results show that leakage current, breakdown strengths, charge trapping characteristics are influenced by conditions. Larger capacitance increases electrodes, lower currents, higher fields, electron rates observed for fabricated with low NH3:SiH2Cl2 gas ratio deposited at temperature. These also expected to have a thicker bottom...
Abstract Culture ponds were stocked with 10-d-old larvae of striped bass (Morone saxatilis) and bass–white hybrids (M. saxatills × M. chrysops) sampled a tow net 36–96 h later. Excessive stocking mortality could be detected when sampling occurred 36–48 after stocking, but not at later times. A threshold value six per indicated adequate survival.
The ionosphere plays an important role in the performance of critical civilian and defense communication systems. Perturbation studies allow us to investigate improve communications that rely on as well develop new applications. A key instrument ionospheric modification is heater, a powerful high frequency transmitter perturbs properties plasma by modulating electron temperature at preselected altitudes. latest technology uses stationary facilities, among which HAARP largest. There are...
The resonant circuit in an Inductive Output Tube (IOT) extracts the kinetic energy of modulated electron beam converting it to electromagnetic energy. For application considered here, mobile low-frequency sources (5-10 MHz) for ionospheric heating, high efficiency is important, and thus class D operation desired. broad frequency range requires be tunable, need a constant decelerating voltage impedance. This paper discusses design construction with highly coupled transformer that has above...
Microwave photonic circuits are capable of processing large bandwidths radiometric data ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$>$ </tex-math></inline-formula> 100 GHz) in an unprecedented number analog spectrometer channels 100) at narrow spectral resolutions (< MHz) and a small device footprint. However, simultaneously this entire bandwidth requires dynamic range. In work, heterodyne...
A mobile heater for ionospheric modification studies will require a new megawatt class RF source operating with an antenna array that is 1/20 the area of HAARP [1]. In order to deliver effective power density comparable HAARP, total must be in range 16 MW, thus demanding highly efficient sources [2]. The design we are currently pursuing utilizes grid-less electron gun uses mod-anode turn thin annular beam on and off D operation. passed through decelerating gap its kinetic energy extracted...