| Plantenna or a Plant made to Function as an Antenna |
30-Oct-2007 |
12 pages |
| Authors:
V Chandraselar; COLORADO STATE UNIV FORT COLLINS
|
 | The Plantenna project has the overlying goal to simply use a plant as an antenna. To do this, special plants called metal hyper accumulators are being tested to observe any antenna like properties. The testing so far has been focused at finding an appropriate testing procedure while analyzing the basic impedance properties of plants concerning the relationships between impedance and test frequency and impedance and plant length. This report will ... |
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| Magnetic Random Access Memory for Embedded Computing |
29 OCT 2007 |
212 pages |
| Authors:
Gregory W. Donohoe; IDAHO UNIV MOSCOW DEPT OF ELECTRICAL ENGINEERING
|
| The goal of this research was to develop an embedded magnetic memory technology to be integrated into Complementary Metal Oxide Semiconductor (CMOS) integrated circuit fabrication process to provide radiation-hard, logic elements and small random-access memories. The goal is not to provide large scale, bulk memory, but latches and flip flops that serve as state and data registers for sequential logic, and configuration registers for configurable logic. The benefits to spacecraft ... |
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| Synthesis of Nanostructured LaB6 Powders |
25-Oct-2007 |
10 pages |
| Authors:
Olivia A Graeve; NEVADA UNIV RENO
|
| Nanocrystalline powders of LaB6 with an average crystallite size of 20 nm, as determined from x-ray diffraction analysis, have been obtained using a combustion synthesis technique that makes use of lanthanum nitrate, boron, and carbohydrazide as precursors. The optimum fuel-to-oxidizer ratio was found to be 0.25, which is quite low compared to typical combustion synthesis experiments. The powders are phase-pure except for about a 3 mol% contamination of LaBO3. |
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| Applications of Nanotechnology in Biomimetics and Quantum Computing |
23 OCT 2007 |
4 pages |
| Authors:
Chung-Yuan Mou; NATIONAL TAIWAN UNIV TAIPEI (TAIWAN) DEPT OF CHEMISTRY
|
| The application of pulsed electron paramagnetic resonance "EPR" technique is used in quantum computing. Polarized electron spin created in the photo-excitation of organic molecules is used as the basis of quantum bit. The quantum coherence and superposition effects of the polarized electron spin at the level anti-crossing "LAC" region under the influence of an external magnetic field and microwave pulses is examined. Highly polarized state is present only during the ... |
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| Novel Magnetic Devices |
12 OCT 2007 |
7 pages |
| Authors:
Ivan Schuller; CALIFORNIA UNIV SAN DIEGO LA JOLLA OFFICE OF CONTRACT AND GRANT ADMINISTRATION
|
| This project was dedicated to the development of novel magnetic devices relevant to applications in the fields of sensors, storage, non-volatile, reprogrammable spin-based electronics. The devices envisioned in this project explored novel physical phenomena and new functionalities not yet explored. More specifically, devices the initial idea was to explore three types of phenomena will be explored: ballistic magnetoresistance, magnetic field proximity effect and spin drag. These three phenomena would then ... |
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| Flex Biohybrid Nanomembranes as a Platform for Multifunctional Sensors |
10 OCT 2007 |
11 pages |
| Authors:
Vladimir V. Tsukruk; GEORGIA INST OF TECH ATLANTA SCHOOL OF TEXTILE AND FIBER ENGINEERING
|
| The main focus of current activities was on synthesis of new branched and peptide-containing molecules and further development of sophisticated freely standing membranes with micropatterned structure. We synthesized several new amphiplilic hyperbranched molecules and silver-binding peptide for further incorporation into membrane film. Freely-standing arrays of carbon nanotubes and gold nanoparticles were fabricated as well and their properties tested with micromechanical studies and Raman spectroscopy. Specifically we studied: flexible nanomembranes with ... |
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| Micro Chemical Oxygen-Iodine Laser (COIL) |
OCT 2007 |
|
| Authors:
Carol Livermore-Clifford; MASSACHUSETTS INST OF TECH CAMBRIDGE
|
 | It has been previously proposed to improve the performance and compactness of chemical oxygen-iodine lasers (COIL) through the replacement of some of their macroscale components with arrays of higher-performing microscale (MEMS) components. In this program, a MEMS singlet oxygen generator (SOG) to power a COIL laser was designed, microfabricated from silicon and glass wafers, and successfully demonstrated. The MEMS SOG contained an array of reaction channels for the chemical reaction ... |
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| Fano Bounds for Compact Antennas. Phase I |
OCT 2007 |
77 pages |
| Authors:
J. C. Allen; J. Meloling; SPACE AND NAVAL WARFARE SYSTEMS CENTER SAN DIEGO CA
|
| Impedance matching is a canonical problem in electrical engineering -- design a matching network that transfers maximum power from a generator to a load. Although the loads in this report are restricted to compact antennas, the mathematical exposition applies to any lumped load. Finding a good matching network is a diffcult numerical optimization problem. Therefore, techniques that compute bounds on the matching provide valuable information. For example, the Fano bounds ... |
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| Synthesis of Biofluidic Microsystems (SYNBIOSYS) |
OCT 2007 |
121 pages |
| Authors:
Tamal Mukherjee; Steinar Hauan; James F. Hoburg; Qiao Lin; CARNEGIE-MELLON UNIV PITTSBURGH PA
|
| This report describes approaches to system-level design tools and methodologies. It incorporates significant advances in a behavioral modeling and simulation methodology for Lab-on-a-chip (LoC) design. This modeling and simulation methodology was developed with optimization for design synthesis in mind, enabling rapid automated design of highly complex biofluidic microsystems. This behavioral modeling methodology involves decomposing a complex LoC system into a small set of elements. Each of the elements is associated ... |
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| Novel Designs and Coupling Schemes for Affordable High Energy Laser Modules |
28 SEP 2007 |
74 pages |
| Authors:
Jerome V. Moloney; Axel Schulzgen; Pavel Polynkin; Masud Mansuripur; Mahmoud Fallahi; Yoel Fink; Chiping Chen; ARIZONA UNIV BOARD OF REGENTS TUCSON
|
| This multi-disciplinary research effort developed new classes of compact, highly-doped Er/Yb phosphate-doped glass fibers as high power, low noise single wavelength, single mode oscillators. Three world record powers in low-noise, single frequency laser oscillators at the eyesafe wavelength of 1.55 micrometers were reported. The project vertically integrated fabrication, testing, and optimization of all components necessary for manufacturing of fiber laser units including highly doped specialty glasses, fiber preforms, fiber drawing ... |
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| Two Cell Josephson Junction Qubits (Briefing Charts) |
25 SEP 2007 |
|
| Authors:
Stanford P. Yukon; AIR FORCE RESEARCH LAB HANSCOM AFB MA SENSORS DIRECTORATE
|
| As an extension of their extreme sensitivity to small DC magnetic fields, superconducting SQIF (Superconducting Quantum Interference Filter) arrays may be employed as sensitive RF sensors. RF SQIF arrays fabricated with high Tc Josephson junctions can be cooled with small Sterling microcoolers. This allows their deployment on UAV and satellite platforms. A key issue is whether high sensitivity RF SQIF sensors are able to detect weak signals among a background ... |
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| UF Biomotor/Biosensor Nanotechnologies |
25 SEP 2007 |
53 pages |
| Authors:
Richard B. Dickinson; Daniel L. Purich; Gary McGuire; Brian Holiday; Denis Wirtz; William Cooke; William Zeile; Suzanne Hens; Kimberly Interliggi; Colin Sturm; FLORIDA UNIV GAINESVILLE
|
| This report contains a summary of activities on the project "UF Biomotor/Biosensor Nanotechnologies". Nanoscale actuators for use as molecular shuttles in biosensing devices were developed based on actin filament end-tracking motors. Novel strategies were developed exploiting these motors and modified substrata to propel and guide motor-coated micro- and nanoparticles using substratum-bound actin filaments with their elongating plus-ends bound to the particle surface. Key accomplishments of this project include (1) optimization ... |
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| Nano-Thermoelectric Devices Fabricated by Ion Beam Writing |
24-Sep-2007 |
31 pages |
| Authors:
Maw K Wu; M N Ou; P C Lee; C T Chen; Y Y Chen; ACADEMIA SINICA NANKANG TAIPEI (TAIWAN) INST OF PHYSICS
|
| A lithographic process has been developed to construct the suspended structure. The self-heating 3W method and measurement systems for nanoscale material have been constructed. The thermal conductivity and specific heat of diameter of 180nm nickel sire are 23 W/m-K and 64.6 J/mol-K (at 25C), respectively. A 30 nano-wire has been fabricated for concept demonstration. |
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| Free Space Measured Loss Comparison of Single and Double Ring Resonators for Negative Index Media |
14 SEP 2007 |
6 pages |
| Authors:
John S. Derov; Beverly W. Turchinetz; James W. Dean; Everett E. Crisman; Alvin J. Drehman; AIR FORCE RESEARCH LAB HANSCOM AFB MA SENSORS DIRECTORATE
|
| Since the first demonstration of negative refractive index using nested or edge coupled split ring resonators and posts, various proposals have been made for improvement of the structures. Loss is an ongoing concern for these media at microwave frequencies and above. One alternate design uses broadside coupled split rings printed front to back on a substrate. This approach, which avoids bianisotropic effects of edge coupled rings, has been demonstrated successfully ... |
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| A Joint Meeting of the US-Korea Workshop on Nanostructured Materials and Nanomanufacturing (5th) and the US-Korea Workshop on Nanoelectronics (3rd). Held in Los Angeles, California on August 8-9, 2006 |
10-Sep-2007 |
12 pages |
| Authors:
H T Hahn; CALIFORNIA UNIV LOS ANGELES
|
| A Joint Meeting of the 3rd US-Korea Workshop on Nanoelectronics and the 5th US-Korea Workshop Nanostructured Materials and Nanomanufacturing was held at the University of California, Los Angeles on 8-9 August 2006. The Meeting started with 6 overview presentations on research programs in the subject areas supported by the AFOSR and the Center for Nanostructured Materials Technology, Korea, respectively. The Nanoelectronics Workshop included 10 U.S. papers and 14 Korean papers ... |
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| Microfabricated Multianalyte Sensor Arrays for Metabolic Monitoring |
01 SEP 2007 |
32 pages |
| Authors:
Michael V. Pishko; PENNSYLVANIA STATE UNIV UNIVERSITY PARK
|
| Glucose sensor arrays were fabricated on gold electrodes on flexible polyimide sheets by cross-linking glucose oxidase and redox polymer using UV-initiated free radical reaction. Using conventional silicon fabrication methods, five-element array Au microdisks were initially fabricated using mid-UV photolithography. Active glucose oxidase were entrapped by hydrogel by UV-intiated photo polymerization with poly(ethylene glycol) diacrylate or PEG-DA on the array electrodes. The fabricated microarray sensors were individually addressable and with no ... |
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| Electro-Magnetic Actuated Valve for MEMS Fuel Metering System |
01-Sep-2007 |
45 pages |
| Authors:
Albert P Pisano; CALIFORNIA UNIV BERKELEY
|
| The goal of this research project is to develop a fuel injection system which delivers the desired ratio of air/fuel mixture to small scale internal combustion engines. Small scale engines require precise fuel control, but the fuel delivery system must be small and low-power. Our research is focused on the development of a planar fuel valve with high fuel delivery rates. The planar nature allows for successful system integration with ... |
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| Hybrid Micro-Electro-Mechanical Tunable Filter |
SEP 2007 |
202 pages |
| Authors:
Edward M. Ochoa; AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING
|
| While advantages such as good thermal stability and processing-chemical compatibilities exist for common monolithic-integrated micro-electro-mechanically tunable filters (MEM-TF) and MEM-tunable vertical cavity surface emitting lasers (MT-VCSEL), they often require full processing to determine device characteristics. Alternatively, the MEM actuators and the optical parts may be fabricated separately, then subsequently bonded. This "hybrid approach" potentially increases design flexibility. Since hybrid techniques allow integration of heterogeneous material systems, "best of breed" compound ... |
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| Modeling Multiferroic Materials |
SEP 2007 |
14 pages |
| Authors:
Greg P. Carman; Gavin Chang; Grayson Bush; CALIFORNIA UNIV LOS ANGELES OFFICE OF CONTRACTS AND GRANTS ADMINISTRATION
|
| The study's focus during the last three years was to analytically understand the effects of material properties as well as configurations on the magnetoelectric coupling in monolithic mangetoelectric materials and magnetostrictive/piezoelectric layered composites (denoted as MELC). The models generated during the last three years provide valuable information on understanding the magnetoelectric coupling behavior and hence maximized the magnetoelectric coupling for magnetoelectric system. The first part of the efforts had been ... |
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| Analysis of Time-History data of Forces and Motions Measured at Towing Facilities |
SEP 2007 |
41 pages |
| Authors:
Young S. Hong; Anne Fullerton; NAVAL SURFACE WARFARE CENTER CARDEROCK DIV BETHESDA MD
|
| Methods to filter and to analyze measured data are described and the numerical results are validated with the generated data. A lowpass filter is used to eliminate the noise of the measured data. The methods of zero crossing, sine function and spectral analysis are applied to compute the amplitudes, periods and phase angles. The numerical results of the measured data are compared with those of different methods. When the measured ... |
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| Transformational Element Level Arrays (TELA) Testbed (Preprint) |
SEP 2007 |
27 pages |
| Authors:
Thomas Dalrymple; Jonathan Buck; Peter Buxa; John McCann; Robert Neidhard; Gary Scalzi; Caleb Shreffler; Dan Spendley; Paul Watson; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH AEROSPACE COMPONENTS AND SUBSYSTEMS TECHNOLOGY
|
| The Air Force is in need of antenna technologies to support surveillance needs in a complex Radio Frequency (RF) environment. Requirements dictate the need to find weak and strong emitters simultaneously over broad bandwidth, while resolving emitter data such as angle of arrival and time of arrival for signal identification and tracking. Previous work at AFRL has resulted in many technologies that support these needs. Many components exist today that ... |
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| Multilayer Reconfigurable GPS Antennas and Platform Effects |
SEP 2007 |
19 pages |
| Authors:
Roberto G. Rojas; OHIO STATE UNIV COLUMBUS DEPT OF ELECTRICAL ENGINEERING
|
| The work reported here discusses two topics. First, the design and test of a GPS pattern reconfigurable antenna is reported. It is shown through computer simulations and measurements that the beamwidth of the antenna can be changed by turning diode switches on and off. This antenna concept was developed to minimize the effect of interfering signals incident on the antenna along the horizon. This work also shows that microstrip antennas ... |
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| Wirelessly Networked Digital Phased Array: Analysis and Development of a Phase Synchronization Concept |
SEP 2007 |
88 pages |
| Authors:
Micael Grahn; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The ongoing research of a wirelessly networked aperstructure digital phased array (WNADPA) at NPS has investigated the possibility of using a distributed opportunistic array for radar, where array elements are placed at any available area of the ship structure. This could give an array that is as large as the ship itself, with 360 degrees coverage. It has advantages in the areas of survivability and adaptability, and the profile of ... |
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| Wireless Networks for Beamforming in Distributed Phased Array Radar |
SEP 2007 |
84 pages |
| Authors:
Jose S. Noris; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The Wirelessly Networked Aperstructure Digital Phased Array Radar (WNADPAR) applies three relatively new concepts: Opportunistic, Aperstructure, and Wirelessly Networked Digital Architecture concepts. Using this approach almost the full length of the ship becomes the aperture of the phased array radar by placing the antenna elements at available open areas and having the power supply as the only wired connection. This thesis research addressed the wireless networking of the full-scale radar ... |
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| Characterization, Optimization, and Test of the NPSAT1 MEMS 3-Axis Rate Sensor Suite for Use in Small Satellite Attitude Control |
SEP 2007 |
227 pages |
| Authors:
Thomas S. Pugsley; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| The NPSAT1 project is a Naval Postgraduate School (NPS) educational small satellite combining student education in satellite systems and operations, institutional research, and sponsored experiments with the objective of testing technologies for applications in space flight. The micro-electro-mechanical system (MEMS) rate sensor is one of these experimental technologies. Packaging three of these MEMS sensors together makes a 3-axis rate sensor suite. The MEMS experiment was originally conceived of as a ... |
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| MEMS PolyMUMPS-Based Miniature Microphone for Directional Sound Sensing |
SEP 2007 |
106 pages |
| Authors:
Timothy J. Shivok; NAVAL POSTGRADUATE SCHOOL MONTEREY CA
|
| A miniature directional sound sensor was fabricated using micro-electro-mechanical system (MEMS) technology based on the operational principle of Ormia ochracea fly s hearing organ. The fly uses coupled bars hinged at the center to achieve the directional sound sensing by monitoring the difference in vibration amplitude between them. The MEMS sensor design employed in this thesis was fabricated using the PolyMUMPs process. The sound sensor has two primary vibrational modes ... |
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| Microscale Self-Assembled Electrical Contacts |
SEP 2007 |
38 pages |
| Authors:
Christopher J. Morris; ARMY RESEARCH LAB ADELPHI MD SENSORS AND ELECTRON DEVICES DIRECTORATE
|
| Self-assembly, or the spontaneous organization of parts into larger structures via energy minimization, is an attractive solution to overcome packaging and integration challenges. Capillary forces from a molten alloy can be used to both bond microscale components and make electrical connections between them in a self-assembly process. This report presents a systematic study of a number of metal alloys and self-assembly media with the aim of reducing the metal contact ... |
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| Electrical and Mechanical Behavior of Silver-Coated Polymeric Fibers |
SEP 2007 |
20 pages |
| Authors:
Suzanne Bosselman; ARMY NATICK RESEARCH DEVELOPMENT AND ENGINEERING COMMAND MA NATICK SOLDIER CENTER
|
| The fundamental behavior of electrically-conductive, silver-coated nylon fibers was studied to understand the relationship between the fiber composition and morphology, tensile behavior, and electrical resistance in the strained state, as well as the post-strained or post-damaged state. Environmental effects on electrical resistance were also studied including immersion in aqueous solutions of various pH levels, as well as exposure to elevated temperatures and thermal cycling. Samples of continuous filament yarns (100 ... |
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| InP Transferred Electron Cathodes: Basic to Manufacturing Methods |
29 AUG 2007 |
139 pages |
| Authors:
P. Pianetta; D. Lee; S. Sun; Z. Liu; W. E. Spicer; STANFORD UNIV CA
|
| InP has gained an emerging importance as a negative electron affinity (NEA) transferred electron photocathode (TEP) material in imaging technologies. InP provides itself as a substrate to grow these small band gap materials, and also serves as an efficient electron emitter with a low work function at the surface. The high quantum efficiency (QE) of these TEP is realized by depositing Cs and O2 on the surface of heavily doped ... |
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| Effects of Helicon Wave Propagation Based on a Conical Antenna Design: Part I (Preprint) |
21 AUG 2007 |
32 pages |
| Authors:
Michael P. Reilly; George H. Miley; David E. Kirtley; Justin Koo; Jr. Hargus William A.; AIR FORCE RESEARCH LAB EDWARDS AFB CA PROPULSION DIRECTORATE
|
| An annular field reversed configuration (FRC) plasma concept is being developed by the University of Michigan and AFRL to investigate inductively-coupled high power electric propulsion. Presented is the continued exploration of an annular FRC with specific focus on main bank discharges, magnetized plasma toroid formation, and preliminary investigation into plasma translation. Additional detail is given towards discharge parameter space, optimization of energy input/translation, and predictive scaling laws of magnetic flux, ... |
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| Advanced, Non-Toxic, Anti-Corrosion, Anti-Fouling and Foul-Release Coatings Based on Covalently Attached Monolayers, Multilayers and Polymers |
08 AUG 2007 |
6 pages |
| Authors:
Thomas J. McCarthy; MASSACHUSETTS UNIV AMHERST DEPT OF POLYMER SCIENCE AND ENGINEERING
|
| This report describes 7 publications that led from this grant: Buried Interface Modification Using Supercritical Carbon Dioxide, Controlled Growth of Silicon Dioxide from "Nanoholes" in Silicon-Supported Tris(trimethylsiloxy)silyl Monolayers, Adsorption of Poly(vinyl alcohol) onto Hydrophobic Substrates (2 papers), A General Approach for Hydrophilizing and Chemically Activating Surfaces, Chemical Surface Modification of Poly(p-xylylene) Thin-Films, Nylon Surface Modification (2 papers). |
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| Enhancing the Interfacial and Dynamic Failure Behavior of Advanced Hybrid Structures Using Nanocomposite Materials |
08 AUG 2007 |
16 pages |
| Authors:
Luoyu R. Xu; VANDERBILT UNIV NASHVILLE TN DIV OF SPONSORED RESEARCH
|
| A novel interfacial joint was developed for reducing the interfacial stress levels. The proposed design, inspired by the shape and mechanics of trees, effectively removed the stress singularity at the interfacial joint for most engineering materials through an integrated theoretical and experimental investigation. Significant tensile loading capacity increase was obtained (up to 81%) using this new joint, while the material volume of the new joint actually was reduced. Dynamic tension ... |
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| Development of Process Technologies for High-Performance MOS-Based SiC Power Switching Devices |
01 AUG 2007 |
441 pages |
| Authors:
James A. Cooper; Michael A. Capano; Leonard C. Feldman; Marek Skowronski; John R. Williams; PURDUE UNIV LAFAYETTE IN
|
| In this work we developed the technology for 20 kV insulated gate bipolar transistors (IGBTs) in 4H-SiC. The p-channel IGBT is formed on a 175-micron p-type epilayer on an n+ substrate. The n-IGBT is formed on the C-face of a 200-micron n-type free-standing epilayer. When operated at 300 W/cm2, the p- and n-IGBTs carry 30 and 27 A/cm2 respectively, independent of temperature from 23 deg C to 175 deg C. ... |
|
| Entrapment of Enzymes and Carbon Nanotubes in Biologically Synthesized Silica: Glucose Oxidase-catalyzed Direct Electron Transfer, Preprint |
AUG 2007 |
24 pages |
| Authors:
Dmitri Invitski; Kateryna Artyuskova; Rosalba A. Rincon; Plamen Atanassov; Heather R. Luckarift; Glenn R. Johnson; NEW MEXICO UNIV ALBUQUERQUE DEPT OF CHEMICAL AND NUCLEAR ENGINEERING
|
| This work demonstrates a new approach for building bio-inorganic interfaces by integrating biomimetically-derived silica with single-walled carbon nanotubes to create a conductive matrix for immobilization of enzymes. Such a strategy not only allows simple integration into bio-devices but presents an opportunity to intimately interface an enzyme and manifest direct electron transfer features. Biologically-templated silica/carbon nanotube/enzyme composites were evaluated electrochemically and characterized by means of X-ray photoelectron spectroscopy. Voltammetry of the ... |
|
| Ultraviolet Electrically Injected Light Sources With Epitaxial ZnO-Based Heterojunctions |
AUG 2007 |
15 pages |
| Authors:
Pallab Bhattacharya; JAMIE PHILLIPS; MICHIGAN UNIV REGENTS ANN ARBOR DIV OF RESEARCH DEVELOPMENT AND ADMINISTRATION
|
| In this effort, significant emphasis was placed on the epitaxial growth and in situ doping of ZnO for optoelectronic devices. The materials research efforts on ZnO have resulted in device-quality material on sapphire substrates for the desired laser diodes, where the eventual material quality improvements necessary for the devices are anticipated for future growth on ZnO substrates. P-type doping of ZnO was demonstrated using nitrogen, though the p-type behavior was ... |
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| Numerical Modeling of Antenna Near Field |
AUG 2007 |
44 pages |
| Authors:
Surendra Singh; William P. Roach; AIR FORCE RESEARCH LAB BROOKS AFB TX HUMAN EFFECTIVENESS DIR/RADIOFREQUENCY RADIATION BRANCH
|
| This work provides numerical modeling for the near field of a wire antenna. The conventional near field definition is provided along with an explanation for the maximum power density in the near field. Numerical results are provided for the electric and magnetic fields in the near field region. The results obtained from the model are shown to compare very well with data available in the literature for the thin wire ... |
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| Peptide-Assembled Optically Responsive Nanoparticle Complexes |
AUG 2007 |
7 pages |
| Authors:
Joseph M. Slocik; Felicia Tam; Naomi J. Halas; Rajesh R. Naik; AIR FORCE RESEARCH LAB WRIGHT-PATTERSON AFB OH MATERIALS AND MANUFACTURING DIRECTORATE
|
| The design of active nanostructures whose form and properties can be modulated by remote means is an important challenge in nanoscience. Here we report two types of active nanoparticle complexes, with properties controlled by near-infrared illumination, resulting from the assembly of photothermally responsive plasmonic nanoparticles with thermally labile biomolecular linkers. Au nanoshells (NS) and quantum dots (QD) are assembled using coiled-coil peptides into NS-NS and NS-QD complexes. Illumination of the ... |
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| Advanced Non-Linear Control Algorithms Applied to Design Highly Maneuverable Autonomous Underwater Vehicles (AUVs) |
Aug-2007 |
7 pages |
| Authors:
Paul Miller; Vladimir Djapic; Rich Arrieta; Jay A Farrell; SPACE AND NAVAL WARFARE SYSTEMS COMMAND SAN DIEGO CA SIMULATION AND HUMAN SYSTEMS TECHNOLOGY DIV
|
| An increasing variety of sensors are becoming available for use onboard autonomous vehicles. Given these enhanced sensing capabilities, scientific and military personnel are interested in exploiting autonomous vehicles for increasingly complex missions. Most of these missions require the vehicle to function in complex, cluttered environments and react to changing environmental parameters. The present state-of-art vehicles are not maneuverable enough to successfully accomplish most of these tasks. In this research, a ... |
|
| Development of an Ultralight Pulse Gas Metal ARC Welding System for Shipyard Applications |
27 JUL 2007 |
40 pages |
| Authors:
Neil D. Fichtelberg; GENERAL DYNAMICS GROTON CT ELECTRIC BOAT DIV
|
| A significant cost in shipbuilding is setup during unit erection and outfitting to support welding operations. For small welding jobs such as hanger and tack welding, the labor associated with equipment relocation and setup can be a large part of the total cost of welding. This is primarily due to the need to move large and cumbersome welding equipment and cables through confined structures. As a result, many hangers and ... |
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| Addressable Immobilized Ion Channels: Optimization of Ion Channels Tethered to Device Surfaces |
25 JUL 2007 |
6 pages |
| Authors:
Randy Duran; FLORIDA UNIV GAINESVILLE
|
| This work is performed by a team at Florida, Mainz, Texas, Agave Biosystems and Miami. We are attempting to develop a sensitive and selective biomolecular detection system based on arrays ion channel covalently tethered over microelectronic devices. The technical approach involves inserting ion channels in non-native membrane bilayers, characterizing and optimizing the single channel stochastic response, and tethering these assemblies over device gate surfaces. Enhancing the stability of the assemblies ... |
|
| Electrical Filter System Using Multi-Stage Photonic Bandgap Resonator |
18 JUL 2007 |
9 pages |
| Authors:
Derke R. Hughes; DEPARTMENT OF THE NAVY WASHINGTON DC
|
| An electrical filter system includes a transmission line and three or more separated photonic bandgap (PBG) structures positioned successively therealong. |
|
| Stroboscopic Imaging Interferometer for MEMS Performance Measurement |
15 JUL 2007 |
21 pages |
| Authors:
J. A. Conway; J. V. Osborn; J. D. Fowler; AEROSPACE CORP EL SEGUNDO CA LAB OPERATIONS
|
| The insertion of MEMS components into aerospace systems requires advanced testing to characterize performance in a space environment. Here we report a novel stroboscopic interferometer test system that measures nanometer-scale displacements of moving MEMS devices. By combining video imagery and phase-shift interferometry with an environmental chamber, rapid visualization of the dynamic device motion under the actual operational conditions can be measured. The utility of this system is further enhanced by ... |
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| Design and Simulation of a Programmable Memory/Multiplier Array Using G4-FET Technology |
JUL 2007 |
21 pages |
| Authors:
Jay B. Brockman; Peter M. Kogge; NOTRE DAME UNIV IN OFFICE OF RESEARCH
|
| Field-programmable and mask-programmable gate arrays can greatly reduce the non-recurring costs of ASIC development by reusing both masks and physical design effort across many designs. The downside of gate arrays is that they result in suboptimal implementations in terms of area, speed, and power. In addition, there is very little flexibility in converting logic to memory or vice versa, a problem of increasing importance as memory-intensive applications gain in importance. ... |
|
| A Comparison of SiC Power Switches for High-Rel Defense Applications (preprint) |
JUL 2007 |
6 pages |
| Authors:
Michael S. Mazzola; Jeffrey B. Casady; MISSISSIPPI STATE UNIV MISSISSIPPI STATE CENTER FOR ADVANCED SEMICONDUCTOR PROTOTYPING
|
| SiC VJFETs are an ideal device for a number of power electronics applications, including, but not limited to, high temperature motor drives, switch modules, and DC-DC or DC-AC inverters/converters. These applications are relevant to a number of military applications, such as shipboard power systems, more electric vehicles (including hybrid vehicles), and power conditioning systems in hostile and/or high temperature environments. The SiC VJFETs combine the switching speed of Si MOSFETs ... |
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| Power-Aperture Product, Efficiency, Signal to Noise Ratio and Search Function Time of Weighted Phased Arrays |
JUL 2007 |
|
| Authors:
Aris Alexopoulos; Andrew Shaw; DEFENCE SCIENCE AND TECHNOLOGY ORGANISATION EDINBURGH (AUSTRALIA) ELECTRONIC WARFARE AND RADAR DIVISION
|
| The power-aperture product and efficiency of weighted phased arrays is examined for various windows. The impact on the signal to noise ratio is also investigated for the use of windows on the transmit and receive modes of operation of the array and we examine the dependence of the search function time on the array windows. In determining the search function time to conduct surveillance over a given region of space ... |
|
| Enhancement of Drain-Down Capabilities of Submarine Antennae |
JUL 2007 |
16 pages |
| Authors:
Jim Dimas; Andrew J. Scardino; John A. Lewis; DEFENSE SCIENCE AND TECHNOLOGY ORGANIZATION VICTORIA (AUSTRALIA) MARITIME PLATFORMS DIV
|
| Water droplets on submarine antennae degrade signal transmission and increase signature. To improve antennae coating performance a surface which repels water is required. In this study several experimental coatings were compared for their ability to remove water droplets from their surface. The contact angle of a drop of water on each surface was recorded as well as the hysteresis, which is a measure of how easily a droplet will roll ... |
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| Fabrication of a Lateral Polarity GaN MESFET: An Exploratory Study |
27-Jun-2007 |
16 pages |
| Authors:
Zlatko Sitar; Ramon Collazo; NORTH CAROLINA STATE UNIV AT RALEIGH DEPT OF MATERIALS SCIENCE AND ENGINEERING
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| This report describes exploratory studies in the fabrication of the GaN LPH structures and their application in the fabrication of a depletion-mode metal semiconductor field effect transistors (MESFETs). Exploiting LPH growth technology, and the difference in the electronic properties of the different type of domains, i.e. as grown N-polar domains are conductive and Ga-polar domains are insulating, laterally selective doped areas can be realized for improving contact resistance to the ... |
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| Quadrifilar Helical Antenna Array for Line-of-Sight Communications Above the Ocean Surface |
25 JUN 2007 |
76 pages |
| Authors:
Michael J. Josypenko; John P. Casey; Stephen M. Davis; NAVAL UNDERSEA WARFARE CENTER DIV NEWPORT RI
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| This report describes the development of a linear array consisting of four quadrifilar helical antennas (QHAs) that is mounted on a buoy to support transmit and receive communications at 2.45 GHz along line-of-sight (LOS) paths above a sea water half-space. The array elements are designed to be immune to the multipath interference created by reflections of an incident signal from the surface of the ocean. A novel feed design for ... |
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| The NRL Long-Wavelength Test Array |
22 JUN 2007 |
27 pages |
| Authors:
K. P. Stewart; B. C. Hicks; P. C. Crane; P. S. Ray; C. Gross; E. Polisensky; A. Cohen; N. E. Kassim; K. W. Weiler; NAVAL RESEARCH LAB WASHINGTON DC REMOTE SENSING DIV
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| The NRL Long-Wavelength Test Array (NLTA) was constructed to develop and test active baluns and electrically short dipoles for possible use as the primary wideband receiving elements for an emerging suite of large HF/VHF arrays including the Low Frequency Array (LOFAR) and the Long-Wavelength Array (LWA). Several dipoles of various designs and dimensions have been built and tested. Their useful range is when the dipoles arms are between approximately 1/8 ... |
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| Nascap-2k Self-Consistent Simulations of a VLF Plasma Antenna |
21 JUN 2007 |
17 pages |
| Authors:
M. J. Mandell; V. A. Davis; D. L. Cooke; A. T. Wheelock; C. J. Roth; AIR FORCE RESEARCH LAB HANSCOM AFB MA SPACE VEHICLES DIRECTORATE
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| We simulate the plasma response to a high voltage square wave VLF antenna in Medium Earth Orbit plasma with Nascap-2k. The plasma is modeled with a hybrid Particle-in-cell (PlC) approach with PlC ions and fluid barometric electron densities. The plasma response, collected ion currents, and chassis floating potential are computed self-consistently with a near-square-wave bias applied to the antennas. Particle injection and splitting are used to replenish the plasma depleted ... |
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