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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 73 records · Page 4
All sourcesNASA NTRSDOE OSTI
NASA NTRS1993

A low-power battery ampere-hour meter

A digital device has been developed to meter the current drain of a battery in ampere hours. The device consists of a voltage controlled oscillator (VCO), a frequency divider, an accumulator, and a liquid crystal display. A voltage proportional to load current is converted into a clock signal whose pulse rate is scaled by the frequency divider to the desired engineering units. Final output pulses are counted and displayed. The use of MOSFET and CMOS integrated circuits allows continuous battery-powered operation over a 3-month time period to an accuracy of +/- 2 percent. The instrument will find application where accurate monitoring of battery charge/discharge status is required over long time intervals.

Tripp, John S.↗
NASA NTRS2001

Not Your Ordinary GEM

Through Small Business Innovation Research (SBIR) funding from NASA's Stennis Space Center, Geophex devised a new design for broadband electromagnetic sensors. Geophex developed a patented sensing technology, capable not only of coastal monitoring, but also a variety of other functions, including environmental pollution characterization, groundwater contamination detection, archaeological study, and mineral detection. The new technology is offered in several of the company's products the GEM-2, GEM-2A, and the GEM-3. The Geophex products consist of two primary electromagnetic coils, which are stimulated by alternating currents that generate a magnetic field in the object targeted for investigation. GEM-2 is a handheld, lightweight, programmable, digital device. GEM-2A is an airborne version of the sensor. Suspended from a helicopter, the GEM-2A is used to search for mineral deposits and to survey large tracts of land. The GEM-3 is capable of detecting buried landmines and other active munitions. GEM-3 identifies landmines by their brand names. Because each landmine has its own unique electromagnetic response to the broad frequency band emitted by the GEM-3, bomb identification and disposal strategies are made easier.

Source record↗
NASA NTRS2005

Modern Radar Techniques for Geophysical Applications: Two Examples

The last decade of the evolution of radar was heavily influenced by the rapid increase in the information processing capabilities. Advances in solid state radio HF devices, digital technology, computing architectures and software offered the designers to develop very efficient radars. In designing modern radars the emphasis goes towards the simplification of the system hardware, reduction of overall power, which is compensated by coding and real time signal processing techniques. Radars are commonly employed in geophysical radio soundings like probing the ionosphere; stratosphere-mesosphere measurement, weather forecast, GPR and radio-glaciology etc. In the laboratorio di Geofisica Ambientale of the Istituto Nazionale di Geofisica e Vulcanologia (INGV), Rome, Italy, we developed two pulse compression radars. The first is a HF radar called AIS-INGV; Advanced Ionospheric Sounder designed both for the purpose of research and for routine service of the HF radio wave propagation forecast. The second is a VHF radar called GLACIORADAR, which will be substituting the high power envelope radar used by the Italian Glaciological group. This will be employed in studying the sub glacial structures of Antarctica, giving information about layering, the bed rock and sub glacial lakes if present. These are low power radars, which heavily rely on advanced hardware and powerful real time signal processing. Additional information is included in the original extended abstract.

Arokiasamy, B. J.↗
NASA NTRS2003

Dual-Pump Coherent Anti-Stokes Raman Scattering Temperature and CO2 Concentration Measurements

Measurements of temperature and CO2 concentration using dual-pump coherent anti-Stokes Raman scattering, (CARS) are described. The measurements were performed in laboratory flames,in a room-temperature gas cell, and on an engine test stand at the U.S. Air Force Research Laboratory, Wright-Patterson Air Force Base. A modeless dye laser, a single-mode Nd:YAG laser, and an unintensified back-illuminated charge-coupled device digital camera were used for these measurements. The CARS measurements were performed on a single-laser-shot basis. The standard deviations of the temperatures and CO2 mole fractions determined from single-shot dual-pump CARS spectra in steady laminar propane/air flames were approximately 2 and 10% of the mean values of approximately 2000 K and 0.10, respectively. The precision and accuracy of single-shot temperature measurements obtained from the nitrogen part of the dual-pump CARS system were investigated in detail in near-adiabatic hydrogen/air/CO2 flames. The precision of the CARS temperature measurements was found to be comparable to the best results reported in the literature for conventional two-laser, single-pump CARS. The application of dual-pump CARS for single-shot measurements in a swirl-stabilized combustor fueled with JP-8 was also demonstrated.

Lucht, Robert P.↗
NASA NTRS2010

The New Generation Russian VLBI Network

This paper deals with a new project of the Russian VLBI Network dedicated for Universal Time determinations in quasi on-line mode. The basic principles of the network design and location of antennas are explained. Variants of constructing receiving devices, digital data acquisition system, and phase calibration system are specially considered. The frequency ranges and expected values of noise temperature are given.

Finkelstein, Andrey↗
NASA NTRS2006

Modern Space Craft - Antique Specifications

Spacecraft now and of the future are being controlled by EMC requirements of the past. Little has been done by the launch vehicle/spacecraft manufacturers to abandon MIL-STD-461C which was released in 1986 because most of the electronics equipment being used aboard current launch vehicles is approved by similarity and heritage to MIL-STD-46 1 C and its predecessors. Twenty years later these electronic equipment items are still not tested to today's MIL-STD-461E requirements because there is a risk that the items will fail to meet the requirements and thus the cost will increase if it becomes necessary to redesign the equipment. That cost is insignificant compared with the cost of losing an entire mission! In the 20 years that have elapsed since MIL-STD-461C was released, the EMC environment has undergone major changes. High speed digital devices have been created that have fundamental clock and bus frequencies that span the entire LV/SC frequency range from the Flight Termination Systems through C and S-Band telemetry. Personnel involved in ground operations routinely carry and use hand held transceivers and cellular telephones close by sensitive electronics equipment. There are now many more orbiting receivers and emitters, plus range assets have increased dramatically since 2001. It's way past time to bring requirements up-to-date!

Brewer, Ron↗
NASA NTRSDate not supplied

Identification of Health Events in Astronaut Missions Using Longitudinal Molecular Signature Detection

Individualized health monitoring can now incorporate a precision medicine approach, profiling multiple molecular and physiological measures of health (generalized omics) longitudinally to enable the timely diagnosis and treatment of disease. Such measurements can include blood chemistries, gene expression data, metabolite measurements, and digital device data. We will present our work on extending such an approach to monitoring individual astronaut health for deep space missions. We have developed and implemented novel algorithms to monitor and detect physiolgical state departures from individualized healthy astronaut baselines , utilizing and biologically annotating generalized omics. Our new methods can detect baseline deviations across omics corresponding to potentially adverse medical events. Events pointing to changes in individual health are then compared across individuals to identify common responses and detect changes affecting multiple crewmembers. We show the utility of our methods in detecting temporal health changes across subjects using retrospective Earth and astronaut mission data (metabolite and immune marker data across multiple missions), in order for this technique t o be applicable for future missions.

G I Mias↗
DOE OSTI2023

Late Breaking Results: COPPER: Computation Obfuscation by Producing Permutations for Encoding Randomly

Deployed embedded devices face security risks due to increased ease of physical access to the devices by unauthorized users. Capable adversaries can intercept a device to recover the data in memory, including results of performed sensitive computations. Device owners require data confidentiality on their physically insecure devices. To satisfy this goal we implement a novel method, COPPER (Computation Obfuscation by Producing Permutations for Encoding Randomly), to create data which never exists on the device digitally in plaintext format and which is subsequently used for computation. In this paper we utilize COPPER to calculate a moving average computation on encoded data.

embedded systems↗
NASA NTRS2009

Network device interface for digitally interfacing data channels to a controller via a network

A communications system and method are provided for digitally connecting a plurality of data channels, such as sensors, actuators, and subsystems, to a controller using a network bus. The network device interface interprets commands and data received from the controller and polls the data channels in accordance with these commands. Specifically, the network device interface receives digital commands and data from the controller, and based on these commands and data, communicates with the data channels to either retrieve data in the case of a sensor or send data to activate an actuator. Data retrieved from the sensor is converted into digital signals and transmitted to the controller. Network device interfaces associated with different data channels can coordinate communications with the other interfaces based on either a transition in a command message sent by the bus controller or a synchronous clock signal.

Ellerbrock, Philip J.↗
NASA NTRS2004

Digital Beam Steering Device Based on Decoupled Birefringent Prism Deflector and Polarization Rotator

We describe digital beam deflectors (DBDs) based on liquid crystals. Each stage of the device comprises a polarization rotator and a birefringent prism deflector. The birefringent prism deflects the beam by an angle that depends on polarization of the incident beam. The prism can be made of the uniaxial smectic A (SmA) liquid crystal (LC) or a solid crystal such as yttrium orthovanadate (YVO4). SmA prisms have high birefringence and can be constructed in a variety of shapes, including single prisms and prismatic blazed gratings of different angles and profiles. We address the challenges of uniform alignment of SmA, such as elimination of focal conic domains. Rotation of linear polarization is achieved by an electrically switched twisted nematic (TN) cell. A DBD composed of N rotator-deflector pairs steers the beam into 2(sup N) directions. As an example, we describe a four-stage DBD deflecting normally incident laser beam within the range of +/- 56 mrad with 8 mrad steps. Redirection of the beam is achieved by switching the TN cells.

Pishnyak, Oleg↗
DOE OSTI2021

An adaptive masking method for beam halo measurement by a digital micro mirror device

We report that in high intensity particle beams, irregularities in cathode emission, scattering effects, dark current and space charge forces can lead to a common phenomenon termed beam halo with associated emittance growth, beam loss and overall beam quality degradation. It is of fundamental interest and practical importance to precisely monitor such beam halo, which could offer valuable insights into the experimental strategy for the suppression of this undesired feature. A Digital Micro mirror Device (DMD) is a computer-controlled micro-electrical-mechanical system that contains a compact array of physically independent reflective mirrors. Using a standard DMD, we come up with an adaptive masking method for halo measurement, which demonstrates superior robustness and efficiency comparing to the conventional approaches as confirmed by simulation and experimental results. Our development includes an integrated package of hardware, software and a graphic user interface (GUI) that is robust and portable and can be applied as a beam halo diagnostic for electron guns or radiating charged particle beams in general.

43 PARTICLE ACCELERATORS↗
NASA NTRS1977

A serial digital data communications device

A general purpose computer peripheral device which is used to provide a full-duplex, serial, digital data transmission link between a Xerox Sigma computer and a wide variety of external equipment, including computers, terminals, and special purpose devices is reported. The interface has an extensive set of user defined options to assist the user in establishing the necessary data links. This report describes those options and other features of the serial communications interface and its performance by discussing its application to a particular problem.

Fetter, J. L.↗
NASA NTRS2022

Turning Limitations into Opportunities in the Development of the Orion Medical System: Incorporation of mHealth Devices

INTRODUCTION: Selection of medical devices for the Orion medical system is a complex task which is dependent on the current state of terrestrial technology. In this work we review the interplay between NASA requirements, constraints, and opportunities for synergy during the development of the Orion medical system. METHODS: The “plan to treat” list of conditions, and subsequently the medical resource list for the Orion Artemis II lunar flyby mission was completed using semi-quantitative methods. During this process, some medical resources were excluded to comply with mass and volume limits, while other resources applicable to multiple medical requirements were prioritized for inclusion. Choices were also examined considering NASA level of care standards for the Artemis design reference missions. As a means to optimize capabilities in spite of mass and volume constraints, ideas for integration of multiple devices into a single platform were explored, including a ‘hackathon’ challenge which was conducted to generate and evaluate concepts for combining medical devices into a single app-based mobile device (ultrasound, ECG, etc.). RESULTS: The Orion team identified 128 medical conditions that we “plan to treat”, with 139 unique medical resources to address these conditions, including 5 digital diagnostic devices (ECG, otoscope, stethoscope, pulse oximeter, and blood pressure monitor). During selection of these digital devices the team noted that miniaturized medical devices often use mobile device platforms (mHealth), some displaying and transmitting data exclusively via mobile device. Of the 5 initially selected devices, all are capable of mobile connection, one which cannot function without a mobile device (ECG). Furthermore, only one of these devices connects natively to a Windows platform, which is currently the only operating system available on Orion. DISCUSSION: Significant savings in mass and volume as well as training and usability improvements can be achieved by leveraging mHealth technologies. However, the platform presents significant challenges for deployment within the Artemis Program including lack of internet connectivity, incompatible operating systems, and radiation concerns. Each of these drawbacks are surmountable with investment in the supporting vehicle architecture, which may become necessary to support the technology trends seen in commercially available medical devices today. Objective: Learn about the opportunities and challenges of leveraging mHealth devices in the development of medical capabilities for austere environments. Learn about the constraints of the NASA spaceflight environment with regards to digital medical device integration.

Douglas Ebert↗
NASA NTRS1980

Study of digital charge coupled devices

Charge coupled devices represent unique usage of the metal oxide semiconductor concept. These devices can sample an AC signal at the input, transfer charge proportional to this signal through the CCD shift register and then provide an output of the same frequency and shape as the input. The delay time between input and output is controlled by the CCD operating frequency and the number of stages in the shift resistor. This work is a reliability evaluation of the buried channel and surface channel CCD technologies. The constructions are analyzed, failure modes are described, and test results are reported.

Wilson, D. D.↗
DOE OSTI2020

Detecting compounds in microfluidic droplets using mass spectrometry

Disclosed herein are devices and methods for detecting compounds in droplets using mass spectrometry. In some embodiments, the device comprises: a microfluidics-MS (microMS) device, wherein the microMS device comprises: a droplet-to-digital microfluidic device, wherein the droplet-to-digital microfluidic device comprises: a glass layer; an electrode layer comprising chrome electrodes etched onto one side of the glass layer; a dielectric layer configured for electrowetting; and a microfluidics layer comprising channels, pockets, and a droplet generator, for example a T-junction droplet generator, wherein the pockets are connected to the channels; and a mass spectrometry plate, wherein the mass spectrometry plate is reversibly sealed to the microfluidic device.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗