A5042800360- Plasma Diagnostics and Applications
- Astro and Planetary Science
- Ionosphere and magnetosphere dynamics
- Planetary Science and Exploration
- Speech and Audio Processing
- Radiation Effects in Electronics
- Solar and Space Plasma Dynamics
- Space Satellite Systems and Control
- Spacecraft Design and Technology
- Electrohydrodynamics and Fluid Dynamics
- Spacecraft and Cryogenic Technologies
- Magnetic confinement fusion research
- Semantic Web and Ontologies
- Space Exploration and Technology
- Silicone and Siloxane Chemistry
- Structural Health Monitoring Techniques
- Global Financial Crisis and Policies
- Particle accelerators and beam dynamics
- Advanced Adaptive Filtering Techniques
- Market Dynamics and Volatility
- solar cell performance optimization
- Digital Filter Design and Implementation
- Analog and Mixed-Signal Circuit Design
- Data Quality and Management
- Advanced Data Compression Techniques
Marshall Space Flight Center
2013-2023
International Monetary Fund
2007-2021
Mitre (United States)
2017
National Aeronautics and Space Administration
2006-2015
PDS (United States)
2014
RTX (United States)
2012
ON Semiconductor (Canada)
2010
Technical University of Darmstadt
2005
University of California, Berkeley
2002
Western University
1993-2002
Filterbanks for digital hearing aids must use significantly different criteria than those designed coding applications. For aids, the filterbank channel gains be adjustable over a large dynamic range to compensate loss. This adjustability violates alias cancellation properties of critically sampled filterbanks coding. paper describes exclusively aid Consideration will given extremely limited memory, low delay and power requirements that met in typical application.
ProblemCurrently, there is no agreed on methodology for development of ontologies, and consensus how ontologies should be evaluated.Consequently, evaluation techniques tools are not widely utilized in the ontologies.This can lead to poor quality an obstacle successful deployment as a technology. ApproachThe goal Ontology Summit 2013 was create guidance ontology developers users evaluate ontologies.Over period four months variety approaches were discussed by participants, who represented...
The role that ontologies play or can in designing and employing semantic technologies has been widely acknowledged by the Semantic Web Linked Data communities.But level of collaboration between these communities Applied Ontology community much less than expected.Also, ontological techniques appear to be marginalized use Big its applications.To understand this situation foster greater collaboration, Summit 2014 brought together representatives from Web, Data, communities, address three basic...
©International Monetary Fund.Not for Redistribution 1 Other market-based mechanisms to finance climate adaptation needs including through greater private sector involvement such as green bonds, catastrophe debt swaps and insurance are either still emerging require further exploration or not relevant PICs.Thus,
A set of multijunction GaAs/Ge solar array test coupons provided by Space Systems/Loral was subjected to a sequence five-year increments combined space environmental exposure tests. The capture an integrated design intended for use in geosynchronous (GEO) environment. key component this campaign is performing electrostatic discharge (ESD) tests the inverted gradient mode. protocol ESD based on ISO standard testing panels [ISO-11221]. schematic reference has been modified with System/Loral...
There are many connections among artificial intelligence, learning, reasoning and ontologies. The Ontology Summit 2017 explored, identified articulated the relationships these areas. As part of general advocacy Ontolog Forum to bring ontology science engineering into ma instream, we endeavored abstract a conversational toolkit from sessions that may facilitate discussion knowledge sharing amongst stakeholders concerned with topic. Our findings supported examples various domains interest....
Low-power and low-voltage embedded microcontrollers are required more for portable applications. Power reduction can be addressed at the software level as well architecture while searching to reduce number of executed instructions a given task. An 8-b RISC-like pipelined microcontroller family is presented achieving one clock per instruction. It compared various architectures existing microcontrollers. According an efficiency model taking into account registers, cores provide four ten times...
The floating potential measurement unit (FPMU) is a multiprobe package designed to measure the of International Space Station (ISS) as well density and temperature local ionospheric plasma environment. purpose FPMU provide direct measurements ISS spacecraft charging continuing construction leads dramatic changes in size configuration. data are used for refinement validation models evaluate severity frequency occurrence hazards. also effectiveness proposed hazard controls. consists four...
The purpose of this test program is to understand the changes and degradation space solar array panel components, including its electrostatic discharge (ESD) mitigation design features in their integrated form, after multiple years (up 15) simulated Earth geosynchronous (GEO) environment. A set multijunction GaAs/Ge coupons was subjected five-year increments combined environmental exposure tests. These tests consisted following: ultraviolet (UV) radiation, ESD, electron/proton particle...
Multi-channel compression schemes are a practical methods of mapping the wide dynamic range speech signals into reduced hearing impaired listeners. These systems address two shortcomings single-channel systems: (1) reduction gain as result narrow-band non-speech stimuli and (2) that often occurs when high-frequency components followed by intense low-frequency components. They also provide frequency-dependent ratios needed many newer supra-threshold fitting strategies (e.g., DSL I/O). This...
Simulation of the low Earth orbit (LEO) plasma environment in ground-based vacuum facilities is important for studies spacecraft interaction with ionospheric plasmas. In this paper we describe design and performance a magnetic filter-equipped source. Experimental data collected expanding downstream source suggest it good candidate use as LEO simulator that has very electron temperature contains streaming ions—the encountered by satellites LEO. Adjustable operating conditions flow rate,...
Ontologies and related reasoning systems are key to the facilitation of semantic integration interoperability. But several questions involved. How do we define tools, methodologies frameworks which support this interoperability? What is required achieve optimal performance ac ross applications domains? frame conversation when discussing role ontologies in interoperability with various stakeholders? Ontology Summit 2016 explored these questions. This document a summary Summit, where present...
The International Space Station (ISS) will be the largest, highest power spacecraft placed in orbit. Because of this design electrical system diverged markedly from previous systems. solar arrays operate at 160 V and distribution voltage 120 V. structure is grounded to negative side so under right circumstances it possible drive ISS potential very negative. A plasma contactor has been added provide control relative ambient plasma. requirement that not greater than 40 positive or local What...
It is generally agreed that the interpretation of information, in any form, context-dependent. The goal recent Ontology Summit 2018 was to explore various relationships spanning ontology and context. This article end product summit associated symposium. describes motivation for creating explicit, formal context specifications, discusses approaches finding, understanding formalizing We present this work materials with foster research development contexts drive towards context-aware solutions...
The first preliminary results are reported from the U.S. Round-Robin Test on Plasma Expansion Speed. tests were performed at NASA Glenn Research Center two coupons (six strings) of International Space Station (ISS) solar cell arrays, with a separate small array to obtain arcs (because it is so difficult get ISS arrays arc). used because they have no exposed interconnects act as bare current collectors and confuse experimental results. preconstructed strings laid out approximately parallel...
Tests of arcing and current collection in simulated-space-plasma conditions have been performed at the National Aeronautics Space Administration (NASA) Glenn Research Center (GRC) Cleveland, OH, for over 30 years Marshall Flight (MSFC) Huntsville, AL, almost as long. During this period, proper test an accurate meaningful space simulation worked out, comparisons with actual performance spaceflight tests real operational satellites made, NASA has achieved authors' own internal standards...
The validation of the floating potential measurement unit (FPMU) plasma density and temperature measurements is an important step in process evaluating International Space Station (ISS) spacecraft charging issues including vehicle arcing hazards to crew during extravehicular activities. highest potentials observed on are due combined V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">sp</sub> times B effects a large collection ionospheric...
To reduce the incidence of surgical site infections, preoperative prophylactic antibiotics should be administered within 60 minutes before initial incision is made. A recent study and anecdotal observations, however, indicate that rates for compliance with these guidelines are low. quality improvement project was undertaken at a Florida health care facility to determine if implementing changes in processes would increase antibiotic administration guidelines. After strategies were...
The Langmuir probe (LP) is generally accepted as an effective and relatively simple <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in situ</i> space plasma instrument (plasma density, electron temperature, spacecraft potential). As LPs transition to small spacecraft, their implementation encounters new technical challenges. For example, a negative charge induced on the while positively biasing LP due surface area ratios (spacecraft ≪ 1000)....
With the negative grounding of 160V Photovoltaic (PV) arrays, International Space Station (ISS) can experience varied and interesting charging events. Since August 2006, there has been a multi-probe p ackage, called Floating Potential Measurement Unit (FPMU), availa ble to provide redundant measurements floating potential th e ISS as well density temperature local plasma environment. The FPMU operated during intermittent data campaigns since 2006 collected over 160 days information reg...
The Ontology Summit 2012 explored the current and potential uses of ontology, its methods paradigms, in big systems data: How ontology can be used to design, develop, operate such systems. addressed were not just software
The Compact Auburn Torsatron (CAT) is a low-aspect ratio, continuous coil, toroidal magnetic fusion device. It has two main helical coils: an l = 2, m 5 coil and 1, coil. machine major radius of 53 cm, average plasma 11 steady-state field 1 kG. was designed using optimization scheme that employs the positions winding laws as parameters. Once CAT operational, research program will focus on study flux surfaces ion cyclotron heating. choices compromises encountered in building ratio torsatron...
Covers advancements in spacecraft and tactical strategic missile systems, including subsystem design application, mission analysis, materials structures, developments space sciences, processing manufacturing, operations, applications of technologies to other fields.
The speed plasma propagates across a charged solar panel after primary arc is one of the most important, yet poorly known, quantities in determining Electrostatic Discharge (ESD) currents for spacecraft arcing events. A review literature over last two decades reveals that measured propagation velocity varies by as much an order magnitude. To overcome this deficiency, round-robin set tests was initiated with partners from industry, academia, NASA and U.S. Air Force. This paper will provide...