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Sample records for cu-polyimide flex circuit

  1. Conveyorized Photoresist Stripping Replacement for Flex Circuit Fabrication

    SciTech Connect

    Megan Donahue

    2009-02-24

    A replacement conveyorized photoresist stripping system was characterized to replace the ASI photoresist stripping system. This system uses the qualified ADF-25c chemistry for the fabrication of flex circuits, while the ASI uses the qualified potassium hydroxide chemistry. The stripping process removes photoresist, which is used to protect the copper traces being formed during the etch process.

  2. A 16-channel flex circuit for cryogenic microwave signal transmission

    NASA Astrophysics Data System (ADS)

    McGarey, Patrick; Mani, Hamdi; Wheeler, Caleb; Groppi, Christopher

    2014-07-01

    Heterodyne focal plane arrays used in the terahertz (THz) regime currently require a discrete set of rigid coaxial cables for the transmission of individual intermediate frequency (IF) signals. Consequently, the size of an array is limited to ~10s of pixels due to limited physical space and the complexity of assembly. In order to achieve an array with ~1000 pixels or greater, new interconnections must be developed capable of carrying multiple IF signals on a single carrier which is flexible, robust to noise, and terminated with a high density RF connector. As an intermediate step to the development of a ~1000 pixel heterodyne focal plane array, the Kilopixel Array Pathfinder Project (KAPPa) has developed a 16 channel IF flex circuit. Initially, design simulations were performed to evaluate various means of high-frequency (1~10 GHz) signal transmission, including microstrip, stripline and coplanar waveguides. The method allowing for the closest signal spacing and greatest resistance to radio frequency interference (RFI) was determined to be stripline. Designs were considered where stripline transitioned to microstrip in order to terminate the signal. As microstrip transmission lines are sensitive to RFI, a design featuring just stripline was evaluated. In both the stripline-to-microstrip and stripline-only designs, a three-layer copper-coated polyimide substrate was used. Signal transitions were accomplished by a signal carrying "hot" via passing through a series of three conductive pads, similar to work by Leib et al. (2010). The transition design essentially mimics a coaxial line, where the radial distance between the pads and the ground plane is optimized in order to achieve desired impedances. In simulation, 50 Ohm impedances were achieved throughout, with crosstalk and return loss limited to -30dB. Terminations are made via an array of Corning Gilbert G3PO blind mate connectors, which are small enough to match the 6mm pixel pitch of the KAPPa focal plane unit

  3. Mechanical and Cryogenic Teting of VLPC Flex Circuits Made by Litchfield, Cirexx, and Speedy Circuit

    SciTech Connect

    Rucinski, R.; /Fermilab

    1998-12-28

    Four flex circuits were tested. They are categorized as: (1) Litchfield narrow; (2) Litchfield wide; (3) Cirexx wide; and (4) Speedy Circuit green. The cross sectional area of copper was calculated from trace resistance measurements. All the flex circuits had an acceptable amount of copper cross section. about 6 e-8 m{sup 2} for all except the Cirexx flex which had 4.5 e-8 m{sup 2}. The thickness of the ribbons was 0.006-inch for the Litchfield and about 0.004-inch for the Cirexx and Speed circuit. The room temperature resistivity ratio (RRR) was measured to be 15 for all the circuits. This was expected and means that the trace material resistivity at helium temperatures is 1/15th of what it is at room temperature. This is good from the standpoint of thermal heat load. Purer copper, with an RRR > 30 would result in an unacceptable heat load. The cryogenic cycling and bending tests to liquid nitrogen proved that both the Cirexx wide and Speedy circuit green were made of acceptable materials. Both Litchfield flex circuits had significant cracking of the coverlay when bent at cold temperatures and are not acceptable. The Litchfield narrow was in bad physical condition to start with and got worse through the testing with many more crazing cracks appearing. The crazing is bad enough that the coverlay began to peel and expose the copper beneath. This candidate is unacceptable. The Litchfield wide started out testing in good condition with no cracks. It ended up with much crazing in the coverlay. Within 1 mm of the edge of the coverlay at the cold end. the copper traces were bulged away from the base material. Traces became nadhered and lifted off of the base material at the ends where the coverlay was not present. Numerous electrical opens (7 out of 24 checked) were found at the end of the testing. Visual inspection of the opens leaves open the possibility that the traces are broken below the coverlay in the cold bend area. Obviously this candidate is unacceptable. The

  4. Self-shielding flex-circuit drift tube, drift tube assembly and method of making

    DOEpatents

    Jones, David Alexander

    2016-04-26

    The present disclosure is directed to an ion mobility drift tube fabricated using flex-circuit technology in which every other drift electrode is on a different layer of the flex-circuit and each drift electrode partially overlaps the adjacent electrodes on the other layer. This results in a self-shielding effect where the drift electrodes themselves shield the interior of the drift tube from unwanted electro-magnetic noise. In addition, this drift tube can be manufactured with an integral flex-heater for temperature control. This design will significantly improve the noise immunity, size, weight, and power requirements of hand-held ion mobility systems such as those used for explosive detection.

  5. [PhysioFlex: a target-controlled self-regulating closed-circuit inhalation anesthesia regulator].

    PubMed

    Nathan, N; Sperandio, M; Erdmann, W; Westerkamp, B; Van Dijk, G; Scherpereel, P; Feiss, P

    1997-01-01

    Physi Flex is the first commercially available apparatus capable for quantitative, or self-regulating target controlled inhalational anaesthesia, with a totally closed circuit, in adults and children. The fresh gas supply to the circuit is intermittent, automatically regulated by continuous monitoring of the volume and composition of the gas mixture in the breathing circuit. The circle system includes, instead of the two conventional one way valves, a blower creating a continuous unidirectional flow at 70 L.min-1. In addition to the CO2-absorber it contains an absorber with carbon, absorbing the anaesthetic vapour when switched into the circuit. The ventilator consists of four ventilating chambers, each one with a membrane separating the patient and the motor compartments. The displacement of the membranes generates and measures the tidal volume. Automatic ventilation is achieved by electric valves and motor gas, and manual ventilation using a bag. Spontaneous ventilation is also possible. The machine is operated via a computer with selects the number of ventilating chambers (one, two or four), and the tidal volume between 50 and 2,000 mL, depending on age, gender and weight of the patient. The computer maintains the gas volume and the gas and vapour concentrations at their preset values. The O2-flow and consumption, the N2O flow and uptake, FICO2 and FETCO2, FI and FET of the volatile anaesthetic, all other important data are displayed in a numerical and graphical form on a color screen and registered for a delayed analysis. The end tidal concentration of the volatile anaesthetic drives a stepmotor with a syringe containing the selected volatile anaesthetic agent with is directly injected into the breathing circuit where it is vaporized. Therefore the concentration of the anaesthetic vapour can be instantaneously increased with this injector at induction and lowered at end of anaesthesia with the carbon absorber, and the fresh gas consumption is significantly

  6. Nonlinear electromagnetic energy harvesters fabricated by rigid-flex printed circuit board technology

    NASA Astrophysics Data System (ADS)

    Chiu, Yi; Hong, Hao-Chiao; Hsu, Wei-Hung

    2015-12-01

    In this paper, a wideband electromagnetic energy harvester designed and fabricated by commercial rigid-flex PCB technology is demonstrated. The rigid FR-4 boards are used for mechanical frames and coil winding whereas the flexible polyimide film is used for mechanical springs and mass platforms. The total dimension of the device is 20 × 20 × 2 mm3. The internal coil resistance is 15 Ω. In vibration tests, nonlinearity can be observed even at 0.1 g vibration level due to the spring hardening effect. The peak frequency was increased as the vibration level increased. The effective bandwidth was increased from 6 Hz at 0.1 g to 21 Hz at 0.5 g and 27 Hz at 1 g, respectivel, due to the hysteresis effect. For a matched load and 1 g vibration at 240 Hz, the maximum output power is 24.5 nW, corresponding to a power density of 31 nW/cm3.

  7. Transmission lines implementation on HDI flex circuits for the CMS tracker upgrade

    NASA Astrophysics Data System (ADS)

    Blanchot, G.; De Canio, F.; Gadek, T.; Honma, A.; Kovacs, M.; Rose, P.; Traversi, G.

    2016-01-01

    The upgrade of the CMS tracker at the HL-LHC relies on hybrid modules built on high density interconnecting flexible circuits. They contain several flip chip readout ASICs having high speed digital ports required for configuration and data readout, implemented as customized Scalable Low-Voltage Signalling (SLVS) differential pairs. This paper presents the connectivity requirements on the CMS tracker hybrids; it compares several transmission line implementations in terms of board area, achievable impedances and expected crosstalk. The properties obtained by means of simulations are compared with measurements made on a dedicated test circuit. The different transmission line implementations are also tested using a custom 65nm SLVS driver and receiver prototype ASIC.

  8. [Femtosecond lenticule extraction (FLEx)].

    PubMed

    Blum, M; Sekundo, W

    2010-10-01

    Starting in 2006 a new "all femto" method of refractive correction for myopia and myopic astigmatism was introduced. This new method was originally introduced as femtosecond lenticule extraction (FLEx) and further developed with a small incision into SMILE (small incision lenticule extraction). To simplify the terminology the manufacturer brought this onto the market in April 2010 as ReLEx (refractive lenticule extraction). In this procedure a lenticule of intrastromal corneal tissue and a flap-like access cut are subsequently cut utilizing the VisuMax® femtosecond system (Carl Zeiss Meditec, Jena, Germany). The lenticule is then manually removed and the flap repositioned (only by FLEx). In approximately 1,000 successful surgical operations only few side effects were found. The number of eyes treated is currently being expanded in order to further standardize this new clinical procedure. PMID:20694728

  9. FLEX: fluorescence explorer

    NASA Astrophysics Data System (ADS)

    Stoll, Marc-Ph.; Court, Andrew; Smorenburg, Kees; Visser, Huib; Crocco, Luiggi; Heilimo, Jyro; Honig, Andre

    1999-12-01

    FLEX is a scientifically driven space mission to provide demonstration/validation of the instrumentation and technique for measuring the natural fluorescence of vegetation in the Fraunhofer lines. The payload consists of high spectral resolution (0.1 - 0.3 nm) CCD imaging grating spectrometer with two channels: one in the red (648 - 664 nm) and one in the blue (391 - 438 nm) for working with several Fraunhofer lines. The across track FOV is 8.4 degrees; ground spatial resolution is better than 0.5 X 0.5 km2. To increase the S/N ratio a steering mirror will be used, if necessary, to 'freeze' the image and also to provide plus or minus 4 degrees across track depointing. Calibration is made by viewing the sun via a diffuser plate switched into the telescope field of view. A separate CCD camera will allow cloud detection and scene identification. A TIR radiometer will provide simultaneous surface temperature measurements. The spacecraft, overall mass estimated at 200 kg, is derived from the ASI-MITA bus which provides all the necessary subsystems and stabilized platform. By use of on-board storage, ground requirements for satellite control and data link are minimized; the possibility of local stations for real time reception/distribution is also envisaged. Provisional orbit characteristics are: LEO sun synchronous, 500 - 900 km altitude. Priority will be given to highest revisit frequency on a sufficient number of selected test sites.

  10. Pressure vessel flex joint

    NASA Technical Reports Server (NTRS)

    Kahn, Jon B. (Inventor)

    1992-01-01

    An airtight, flexible joint is disclosed for the interfacing of two pressure vessels such as between the Space Station docking tunnel and the Space Shuttle Orbiter bulkhead adapter. The joint provides for flexibility while still retaining a structural link between the two vessels required due to the loading created by the internal/external pressure differential. The joint design provides for limiting the axial load carried across the joint to a specific value, a function returned in the Orbiter/Station tunnel interface. The flex joint comprises a floating structural segment which is permanently attached to one of the pressure vessels through the use of an inflatable seal. The geometric configuration of the joint causes the tension between the vessels created by the internal gas pressure to compress the inflatable seal. The inflation pressure of the seal is kept at a value above the internal/external pressure differential of the vessels in order to maintain a controlled distance between the floating segment and pressure vessel. The inflatable seal consists of either a hollow torus-shaped flexible bladder or two rolling convoluted diaphragm seals which may be reinforced by a system of straps or fabric anchored to the hard structures. The joint acts as a flexible link to allow both angular motion and lateral displacement while it still contains the internal pressure and holds the axial tension between the vessels.

  11. Resistive flex sensors: a survey

    NASA Astrophysics Data System (ADS)

    Saggio, Giovanni; Riillo, Francesco; Sbernini, Laura; Quitadamo, Lucia Rita

    2016-01-01

    Resistive flex sensors can be used to measure bending or flexing with relatively little effort and a relatively low budget. Their lightness, compactness, robustness, measurement effectiveness and low power consumption make these sensors useful for manifold applications in diverse fields. Here, we provide a comprehensive survey of resistive flex sensors, taking into account their working principles, manufacturing aspects, electrical characteristics and equivalent models, useful front-end conditioning circuitry, and physic-bio-chemical aspects. Particular effort is devoted to reporting on and analyzing several applications of resistive flex sensors, related to the measurement of body position and motion, and to the implementation of artificial devices. In relation to the human body, we consider the utilization of resistive flex sensors for the measurement of physical activity and for the development of interaction/interface devices driven by human gestures. Concerning artificial devices, we deal with applications related to the automotive field, robots, orthosis and prosthesis, musical instruments and measuring tools. The presented literature is collected from different sources, including bibliographic databases, company press releases, patents, master’s theses and PhD theses.

  12. Flex bearing UUEC, volume 2

    NASA Technical Reports Server (NTRS)

    Clapper, M. L.

    1993-01-01

    This volume, Volume 2, of this Flex Bearing UUEC Final Report documents findings and data pertaining to Team B's tasks. Team B was organized as one of two sub-teams of the Unplanned/Unintended Event or Condition (UUEC) board established per InterOffice Memorandum (IOM) A100-FY93-072. Team A determined the cause of the unacceptable unbonds (referred to as 'heat-affect' unbonds), including the initial, light rust film, in the FSM #3 flex bearing was overheating of the Forward End Ring (FER) during cure, specifically in zone 8 of the mold. Team A's findings are documented in Volume 1 of this report. Team B developed flight rationale for existing bearings, based on absence or presence of an unpropitious unbond condition like that in FSM #3's flex bearing.

  13. The FLEX/32 multicomputing environment

    NASA Technical Reports Server (NTRS)

    Matelan, N.

    1984-01-01

    The FLEX/32 Multicomputer is a generic environment for cooperating multiple processors. The FLEX/32 supports a number of different processors, making it heterogeneous in terms of the instruction sets it supports, and homogeneous in its ability to provide consistent storage and input/output facilities to its differing processors. These facilities are accessed through standard 32-bit VMEbus connections. The FLEX/32 supports the full UNIX System V Operating System and languages associated with it, plus the extended ConCurrent C and Concurrent FORTRAN 77 languages that allow programming of concurrent software at a high level. Direct programming support at all levels is provided by the environment hardware for concurrent software execution and optimization, including hardware support for shared resource access arbitration, conditional critical region arbitration, and interprocessor messages.

  14. FlexMod Scheduling Redux

    ERIC Educational Resources Information Center

    Murray, Shannon

    2008-01-01

    Flexible modular scheduling (flex mod)--a schedule philosophy and system that has been in place at Wausau West High School in Wausau, Wisconsin, for the last 35 years and aligns nicely with current research on student learning--is getting more and more attention from high school administrators across the country. Flexible modular scheduling was…

  15. Flex joint incorporating enclosed conductors

    SciTech Connect

    Tomek, M.L.

    1989-06-27

    This patent describes a downhole elongate oil tool adapted to flex as required in placing the elongate tool in a crooked well borehole wherein electrical signals are transmitted along conductors along the elongate tool. The elongate tool incorporating a flex tool consists of: (a) a generally spherical knuckle; (b) a surrounding socket engaging the knuckle with a limited rotational range relative to a defined axis through the knuckle and socket; (c) a passage through the knuckle opening at an outlet into the socket; (d) a serially communicated passage through the socket aligned with the knuckle; (e) means cooperative with the knuckle and the socket; (1) permitting flexure in a conic angle relative to an axis through the knuckle and socket; and (2) preventing relative axial rotation between the knuckle and the socket; and (f) means for filling the passages with a pressure isolated oil bath for contacting structural components in the passages, and further wherein the oil bath is pressure isolated by a piston responsive to external fluid pressure in the well borehole to sustain a pressure on the oil bath equal to and in excess of prevailing external pressure.

  16. City FLEX 89: Meeting the Challenge.

    ERIC Educational Resources Information Center

    Alfano, Kathy

    Information is provided on San Diego City College's Flex 89 Program, a 3-day staff development effort offered for the college's administrators, full-time and adjunct faculty, and classified staff. The packet includes the flyer sent to all participants, the Flex Catalog and registration form, an example of an enrollment confirmation, the program…

  17. Flex-Time. A Catalyst Occasional Paper.

    ERIC Educational Resources Information Center

    Catalyst, New York, NY.

    Contains history, case studies, and discussion of the use and benefits of flex-time employment, a pattern of working hours in which individual employees begin and end their work day at times of their choice, within certain limits, as long as they work a prescribed number of hours. The paper addresses the following topics: (1) What is flex-time,…

  18. LARC-SI Flatwire Twin Conduction Circuits

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Eight 2-line, L-shaped gold flex circuits have been imprinted on 1-mil LARC-SI. Each circuit was embedded in a space-applications trapezoidal truss made of carbon fiber reinforced resin composite (with protruding ends) to facilitate electrical connection of electronic devices mounted on the truss. LARC-SI is an advanced polymer highly suitable for multi layered electrical circuits.

  19. Bimaterial Thermal Strip With Increased Flexing

    NASA Technical Reports Server (NTRS)

    Morrison, Andrew D.

    1994-01-01

    In proposed bimaterial thermal strip, one layer has negative coefficient of thermal expansion, thereby increasing difference between coefficients of thermal expansion of two outer layers and consequently increasing flexing caused by change in temperature. Proposed bimaterial strips used in thermostats.

  20. 12 CFR 742.4 - RegFlex Relief.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false RegFlex Relief. 742.4 Section 742.4 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS REGULATORY FLEXIBILITY PROGRAM § 742.4 RegFlex Relief. (a) Exemptions. RegFlex credit unions are exempt from the following regulatory restrictions: (1)...

  1. Flex-gear electrical power transmission

    NASA Technical Reports Server (NTRS)

    Vranish, John; Peritt, Jonathan

    1993-01-01

    This study was conducted to develop an alternative way of transferring electricity across a continuously rotating joint, with little wear and the potential for low electrical noise. The problems with wires, slip rings, electromagnetic couplings, and recently invented roll-rings are discussed. Flex-gears, an improvement of roll-rings, are described. An entire class of flexgear devices is developed. Finally, the preferred flex-gear device is optimized for maximum electrical contact and analyzed for average mechanical power loss and maximum stress. For a device diameter of six inches, the preferred device is predicted to have a total electrical contact area of 0.066 square inches. In the preferred device, a small amount of internal sliding produces a 0.003 inch-pound torque that resists the motion of the device.

  2. Deployment of FlexCHP System

    SciTech Connect

    Cygan, David

    2015-11-01

    The Gas Technology Institute (GTI), along with its partner Integrated CHP Systems Corporation, has developed and demonstrated an Ultra-Low-Nitrogen Oxide (ULN) Flexible Combined Heat and Power (FlexCHP) system that packages a state-of-the-art Capstone C65 gas microturbine and Johnston PFXX100 boiler with an innovative natural gas-fired supplemental burner. Supplemental burners add heat as needed in response to facility demand, which increases energy efficiency, but typically raises exhaust NOx levels, degrading local air quality unless a costly and complicated catalytic treatment system is added. The FlexCHP system increases energy efficiency and achieves the 2007 California Air Resource Board (CARB) distributed generation emissions standards for Nitrogen oxides (NOx), Carbon Monoxide (CO), and Total Hydrocarbons (THC) without catalytic exhaust gas treatment. The key to this breakthrough performance is a simple and reliable burner design which utilizes staged combustion with engineered internal recirculation. This ULN burner system successfully uses turbine exhaust as an oxidizer, while achieving high efficiencies and low emissions. In tests at its laboratory facilities in Des Plaines, Illinois, GTI validated the ability of the system to achieve emissions of NOx, CO, and THC below the CARB criteria of 0.07, 0.10, and 0.02 lb/MW-h respectively. The FlexCHP system was installed at the field demonstration site, Inland Empire Foods, in Riverside, California to verify performance of the technology in an applied environment. The resulting Combined Heat and Power (CHP) package promises to make CHP implementation more attractive, mitigate greenhouse gas emissions, and improve the reliability of electricity supply.

  3. Space Station Live: FLEX in Space for Safer Combustion

    NASA Video Gallery

    Flame Extinguishment Experiment (FLEX) Principal Investigator Mark Hickman, from Glenn Research Center, discusses why scientists study flames in space. One reason is to create a safer environment t...

  4. Automated Facility For Cleaning Large Flex Hoses

    NASA Technical Reports Server (NTRS)

    Landry, Louis E.

    1995-01-01

    Technicians no longer exposed to hazardous cleaning materials. Proposed computer-controlled facility cleans bellow-type expansion joints and large flex hoses. Major portions of automated cleaning facility contained in clean room. One piece of equipment in clean room tower in which hose or expansion joint to be cleaned hoisted by hydraulic machinery and hung vertically. Once hose or expansion joint hung in required position, technician initiates programmed cleaning procedure from console on computer monitoring system. Procedure includes degreasing, cleaning with detergents, rinsing, pickling, and passivating operations. After cleaning completed, technician removes hose or expansion joint from tower and wraps open ends to prevent recontamination of interior.

  5. FlexSnap: Flexible Non-sequential Protein Structure Alignment

    PubMed Central

    2010-01-01

    Background Proteins have evolved subject to energetic selection pressure for stability and flexibility. Structural similarity between proteins that have gone through conformational changes can be captured effectively if flexibility is considered. Topologically unrelated proteins that preserve secondary structure packing interactions can be detected if both flexibility and Sequential permutations are considered. We propose the FlexSnap algorithm for flexible non-topological protein structural alignment. Results The effectiveness of FlexSnap is demonstrated by measuring the agreement of its alignments with manually curated non-sequential structural alignments. FlexSnap showed competitive results against state-of-the-art algorithms, like DALI, SARF2, MultiProt, FlexProt, and FATCAT. Moreover on the DynDom dataset, FlexSnap reported longer alignments with smaller rmsd. Conclusions We have introduced FlexSnap, a greedy chaining algorithm that reports both sequential and non-sequential alignments and allows twists (hinges). We assessed the quality of the FlexSnap alignments by measuring its agreements with manually curated non-sequential alignments. On the FlexProt dataset, FlexSnap was competitive to state-of-the-art flexible alignment methods. Moreover, we demonstrated the benefits of introducing hinges by showing significant improvements in the alignments reported by FlexSnap for the structure pairs for which rigid alignment methods reported alignments with either low coverage or large rmsd. Availability An implementation of the FlexSnap algorithm will be made available online at http://www.cs.rpi.edu/~zaki/software/flexsnap. PMID:20047669

  6. Evaluation of SRM flex bearing materials and processes

    NASA Technical Reports Server (NTRS)

    Wood, T. E.

    1980-01-01

    Tensile, peel, and shear testing was performed on combinations of primers, adhesives, tycements and rubber compounds cured at various times and temperatures. The materials used in the fabrication of the solid rocket motor flex bearing as well as in other systems were evaluated. A compatibility study between adhesives and tycements was initiated. The flex bearing mold design was reviewed by our tooling experts.

  7. The V-Flex, Triangle Orientation, and Catalan Numbers in Hexaflexagons

    ERIC Educational Resources Information Center

    Iacob, Ionut E.; McLean, T. Bruce; Wang, Hua

    2012-01-01

    Regular hexaflexagons mysteriously change faces as you pinch flex them. This paper describes a different flex, the V-flex, which allows the hexahexaflexagon (with only 9 faces under the pinch flex) to have 3420 faces. The article goes on to explain the classification of triangle orientations in a hexaflexagon and gives an example of the…

  8. Flex fuel polygeneration: Integrating renewable natural gas

    NASA Astrophysics Data System (ADS)

    Kieffer, Matthew

    Flex Fuel Polygeneration (FFPG) is the use of multiple primary energy sources for the production of multiple energy carriers to achieve increased market opportunities. FFPG allows for adjustments in energy supply to meet market fluctuations and increase resiliency to contingencies such as weather disruptions, technological changes, and variations in supply of energy resources. In this study a FFPG plant is examined that uses a combination of the primary energy sources natural gas and renewable natural gas (RNG) derived from MSW and livestock manure and converts them into energy carriers of electricity and fuels through anaerobic digestion (AD), Fischer-Tropsch synthesis (FTS), and gas turbine cycles. Previous techno-economic analyses of conventional energy production plants are combined to obtain equipment and operating costs, and then the 20-year NPVs of the FFPG plant designs are evaluated by static and stochastic simulations. The effects of changing operating parameters are investigated, as well as the number of anaerobic digestion plants on the 20-year NPV of the FTS and FFPG systems.

  9. High Power Flex-Propellant Arcjet Performance

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.

    2011-01-01

    implied nearly frozen flow in the nozzle and yielded performance ranges of 800-1100 sec for hydrogen and 400-600 sec for ammonia. Inferred thrust-to-power ratios were in the range of 30-10 lbf/MWe for hydrogen and 60-20 lbf/MWe for ammonia. Successful completion of this test series represents a fundamental milestone in the progression of high power arcjet technology, and it is hoped that the results may serve as a reliable touchstone for the future development of MW-class regeneratively-cooled flex-propellant plasma rockets.

  10. Attachment method for stacked integrated circuit (IC) chips

    DOEpatents

    Bernhardt, Anthony F.; Malba, Vincent

    1999-01-01

    An attachment method for stacked integrated circuit (IC) chips. The method involves connecting stacked chips, such as DRAM memory chips, to each other and/or to a circuit board. Pads on the individual chips are rerouted to form pads on the side of the chip, after which the chips are stacked on top of each other whereby desired interconnections to other chips or a circuit board can be accomplished via the side-located pads. The pads on the side of a chip are connected to metal lines on a flexible plastic tape (flex) by anisotropically conductive adhesive (ACA). Metal lines on the flex are likewise connected to other pads on chips and/or to pads on a circuit board. In the case of a stack of DRAM chips, pads to corresponding address lines on the various chips may be connected to the same metal line on the flex to form an address bus. This method has the advantage of reducing the number of connections required to be made to the circuit board due to bussing; the flex can accommodate dimensional variation in the alignment of chips in the stack; bonding of the ACA is accomplished at low temperature and is otherwise simpler and less expensive than solder bonding; chips can be bonded to the ACA all at once if the sides of the chips are substantially coplanar, as in the case for stacks of identical chips, such as DRAM.

  11. Attachment method for stacked integrated circuit (IC) chips

    DOEpatents

    Bernhardt, A.F.; Malba, V.

    1999-08-03

    An attachment method for stacked integrated circuit (IC) chips is disclosed. The method involves connecting stacked chips, such as DRAM memory chips, to each other and/or to a circuit board. Pads on the individual chips are rerouted to form pads on the side of the chip, after which the chips are stacked on top of each other whereby desired interconnections to other chips or a circuit board can be accomplished via the side-located pads. The pads on the side of a chip are connected to metal lines on a flexible plastic tape (flex) by anisotropically conductive adhesive (ACA). Metal lines on the flex are likewise connected to other pads on chips and/or to pads on a circuit board. In the case of a stack of DRAM chips, pads to corresponding address lines on the various chips may be connected to the same metal line on the flex to form an address bus. This method has the advantage of reducing the number of connections required to be made to the circuit board due to bussing; the flex can accommodate dimensional variation in the alignment of chips in the stack; bonding of the ACA is accomplished at low temperature and is otherwise simpler and less expensive than solder bonding; chips can be bonded to the ACA all at once if the sides of the chips are substantially coplanar, as in the case for stacks of identical chips, such as DRAM. 12 figs.

  12. flexTMS--a novel repetitive transcranial magnetic stimulation device with freely programmable stimulus currents.

    PubMed

    Gattinger, Norbert; Moessnang, Georg; Gleich, Bernhard

    2012-07-01

    Transcranial magnetic stimulation (TMS) is able to noninvasively excite neuronal populations due to brief magnetic field pulses. The efficiency and the characteristics of stimulation pulse shapes influence the physiological effect of TMS. However, commercial devices allow only a minimum of control of different pulse shapes. Basically, just sinusoidal and monophasic pulse shapes with fixed pulse widths are available. Only few research groups work on TMS devices with controllable pulse parameters such as pulse shape or pulse width. We describe a novel TMS device with a full-bridge circuit topology incorporating four insulated-gate bipolar transistor (IGBT) modules and one energy storage capacitor to generate arbitrary waveforms. This flexible TMS (flexTMS ) device can generate magnetic pulses which can be adjusted with respect to pulse width, polarity, and intensity. Furthermore, the equipment allows us to set paired pulses with a variable interstimulus interval (ISI) from 0 to 20 ms with a step size of 10  μs. All user-defined pulses can be applied continually with repetition rates up to 30 pulses per second (pps) or, respectively, up to 100 pps in theta burst mode. Offering this variety of flexibility, flexTMS will allow the enhancement of existing TMS paradigms and novel research applications. PMID:22531742

  13. Building flexible real-time systems using the Flex language

    NASA Technical Reports Server (NTRS)

    Kenny, Kevin B.; Lin, Kwei-Jay

    1991-01-01

    The design and implementation of a real-time programming language called Flex, which is a derivative of C++, are presented. It is shown how different types of timing requirements might be expressed and enforced in Flex, how they might be fulfilled in a flexible way using different program models, and how the programming environment can help in making binding and scheduling decisions. The timing constraint primitives in Flex are easy to use yet powerful enough to define both independent and relative timing constraints. Program models like imprecise computation and performance polymorphism can carry out flexible real-time programs. In addition, programmers can use a performance measurement tool that produces statistically correct timing models to predict the expected execution time of a program and to help make binding decisions. A real-time programming environment is also presented.

  14. Design of Experiments to Determine Causes of Flex Cable Solder Wicking, Discoloration and Hole Location Defects

    SciTech Connect

    Wolfe, Larry

    2009-04-22

    Design of Experiments (DoE) were developed and performed in an effort to discover and resolve the causes of three different manufacturing issues; large panel voids after Hot Air Solder Leveling (HASL), cable hole locations out of tolerance after lamination and delamination/solder wicking around flat flex cable circuit lands after HASL. Results from a first DoE indicated large panel voids could be eliminated by removing the pre-HASL cleaning. It also revealed eliminating the pre-HASL bake would not be detrimental when using a hard press pad lamination stackup. A second DoE indicated a reduction in hard press pad stackup lamination pressure reduced panel stretch in the y axis approximately 70%. A third DoE illustrated increasing the pre-HASL bake temperature could reduce delamination/solder wicking when using a soft press pad lamination stackup.

  15. Flex Year: A Concept to Optimize Human Resources.

    ERIC Educational Resources Information Center

    Wulf, Gary W.

    1981-01-01

    Flex Year, which was designed to provide a variety of work schedules for employees, tailored to the college or university's needs and the individual's preference, is being used within the university system of New Hampshire. This concept provides for year-round employment with voluntary leaves without pay. (MLW)

  16. Measuring circuit

    DOEpatents

    Sun, Shan C.; Chaprnka, Anthony G.

    1977-01-11

    An automatic gain control circuit functions to adjust the magnitude of an input signal supplied to a measuring circuit to a level within the dynamic range of the measuring circuit while a log-ratio circuit adjusts the magnitude of the output signal from the measuring circuit to the level of the input signal and optimizes the signal-to-noise ratio performance of the measuring circuit.

  17. The UltraFlex solar array qualification testing program

    SciTech Connect

    Jones, P.A.; Harvey, T.J.; Douglas, M.V.

    1995-12-31

    A low-cost, lightweight spacecraft power source can help maximize mission efficiency to meet the realities imposed by today`s reduced space budgets. Solar cell technology advances can improve specific power, however, the issues of large-scale manufacturability and cost diminish their near-term potential. Spacecraft designed in the near future must therefore rely on array advances based on established solar cell technologies to meet the goal of increased specific power at a reasonable cost. A joint ABLE-Spectrolab development program has resulted in just such a solar array, the UltraFlex system. The maturation of the UltraFlex design through a successful flight qualification testing program and the resulting evolution of its performance predictions are reported. End of life (EOL) specific power performance of over 100 W/kg with silicon cells and over 180 W/kg with near term multijunction cells is reported.

  18. Preliminary reliability evaluation of flip chip on flex interconnect technology

    NASA Technical Reports Server (NTRS)

    Shaw, Jack J.; Virmani, Naresh

    1997-01-01

    The study was carried out to evaluate the flip-chip-on-flex (FCOF) interconnection process in order to determine its feasibility for space flight applications. The key objectives were to: develop and apply simple and cost effective process steps needed to manufacture FCOFs and build test samples; perform a preliminary technology validation, and determine any initial environmental or application risks. The FCOF was shown to be simpler and more economical than other chip interconnection schemes.

  19. LANCE Q-flex accelerometer qualification test program

    NASA Astrophysics Data System (ADS)

    Hunter, J. S.; Mitchell, J. N.; Hester, T.; Searcy, D.

    1982-03-01

    This report covers the performance obtained on six Sundstrand Q-Flex accelerometers during the qualification test program for the LANCE missile. The Qualification Test Program was divided into three parts: (1) Flight Assurance Tests (FAT), (2) Storage and Transportation Tests (SATT), and (3) Reliability Overstress Tests (ROT). All testing was performed in accordance with Vought accelerometer procurement specification 704-166C dated 8 June 1978.

  20. An aerodynamic study on flexed blades for VAWT applications

    NASA Astrophysics Data System (ADS)

    Micallef, Daniel; Farrugia, Russell; Sant, Tonio; Mollicone, Pierluigi

    2014-12-01

    There is renewed interest in aerodynamics research of VAWT rotors. Lift type, Darrieus designs sometimes use flexed blades to have an 'egg-beater shape' with an optimum Troposkien geometry to minimize the structural stress on the blades. While straight bladed VAWTs have been investigated in depth through both measurements and numerical modelling, the aerodynamics of flexed blades has not been researched with the same level of detail. Two major effects may have a substantial impact on blade performance. First, flexing at the equator causes relatively strong trailing vorticity to be released. Secondly, the blade performance at each station along the blade is influenced by self-induced velocities due to bound vorticity. The latter is not present in a straight bladed configuration. The aim of this research is to investigate these effects in relation to an innovative 4kW wind turbine concept being developed in collaboration with industry known as a self-adjusting VAWT (or SATVAWT). The approach used in this study is based on experimental and numerical work. A lifting line free-wake vortex model was developed. Wind tunnel power and hot-wire velocity measurements were performed on a scaled down, 60cm high, three bladed model in a closed wind tunnel. Results show a substantial axial wake induction at the equator resulting in a lower power generation at this position. This induction increases with increasing degree of flexure. The self-induced velocities caused by blade bound vorticity at a particular station was found to be relatively small.

  1. Experimental Charging Behavior of Orion UltraFlex Array Designs

    NASA Technical Reports Server (NTRS)

    Golofaro, Joel T.; Vayner, Boris V.; Hillard, Grover B.

    2010-01-01

    The present ground based investigations give the first definitive look describing the charging behavior of Orion UltraFlex arrays in both the Low Earth Orbital (LEO) and geosynchronous (GEO) environments. Note the LEO charging environment also applies to the International Space Station (ISS). The GEO charging environment includes the bounding case for all lunar mission environments. The UltraFlex photovoltaic array technology is targeted to become the sole power system for life support and on-orbit power for the manned Orion Crew Exploration Vehicle (CEV). The purpose of the experimental tests is to gain an understanding of the complex charging behavior to answer some of the basic performance and survivability issues to ascertain if a single UltraFlex array design will be able to cope with the projected worst case LEO and GEO charging environments. Stage 1 LEO plasma testing revealed that all four arrays successfully passed arc threshold bias tests down to -240 V. Stage 2 GEO electron gun charging tests revealed that only the front side area of indium tin oxide coated array designs successfully passed the arc frequency tests

  2. 12 CFR 742.3 - Loss and revocation of RegFlex designation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Loss and revocation of RegFlex designation. 742.3 Section 742.3 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS REGULATORY FLEXIBILITY PROGRAM § 742.3 Loss and revocation of RegFlex designation. (a) Loss of authority. RegFlex authority is lost when...

  3. Experience in using FlexCtrl SCADA for accelerator automation

    NASA Astrophysics Data System (ADS)

    Nikiforov, A.; Aleinikov, V.; Sychev, A.; Borina, I.; Rukavishnikov, A.

    2012-07-01

    The programmed component of the automatic control of accelerators on the basis of licensed software packages (FlexCtrl SCADA, Photon Application Builder, and Cogent DataHub) and an additionally developed library of classes (related to visual programming with regard to functional capabilities and which all together represent an integrated media for producing the automation system) is described in the article. The number of features of the media components and the number of the components themselves can be increased since the developed media is characterized as open.

  4. A stack-based flex-compressive piezoelectric energy harvesting cell for large quasi-static loads

    NASA Astrophysics Data System (ADS)

    Wang, Xianfeng; Shi, Zhifei; Wang, Jianjun; Xiang, Hongjun

    2016-05-01

    In this paper, a flex-compressive piezoelectric energy harvesting cell (F-C PEHC) is proposed. This cell has a large load capacity and adjustable force transmission coefficient assembled from replaceable individual components. A statically indeterminate mechanical model for the cell is established and the theoretical force transmission coefficient is derived based on structural mechanics. An inverse correlation between the force transmission coefficient and the relative stiffness of Element 1’s limbs is found. An experimental study is also conducted to verify the theoretical results. Both weakened and enhanced modes are achieved for this experiment. The maximum power output approaches 4.5 mW at 120 kΩ resistive load under a 4 Hz harmonic excitation with 600 N amplitude for the weakened mode, whereas the maximum power output approaches 17.8 mW at 120 kΩ under corresponding load for the enhanced mode. The experimental measurements of output voltages are compared with the theoretical ones in both weakened and enhanced modes. The experimental measurements of open-circuit voltages are slightly smaller for harmonic excitations with amplitudes that vary from 400 N to 800 N and the errors are within 14%. During the experiment, the maximum load approaches 2.8 kN which is quite large but not the ultimate bearing capacity of the present device. The mechanical model and theoretical transmission coefficient can be used in other flex-compressive mode energy transducers.

  5. ADDER CIRCUIT

    DOEpatents

    Jacobsohn, D.H.; Merrill, L.C.

    1959-01-20

    An improved parallel addition unit is described which is especially adapted for use in electronic digital computers and characterized by propagation of the carry signal through each of a plurality of denominationally ordered stages within a minimum time interval. In its broadest aspects, the invention incorporates a fast multistage parallel digital adder including a plurality of adder circuits, carry-propagation circuit means in all but the most significant digit stage, means for conditioning each carry-propagation circuit during the time period in which information is placed into the adder circuits, and means coupling carry-generation portions of thc adder circuit to the carry propagating means.

  6. Survey of Flex Fuel in 2014. CRC Project E-85-3

    SciTech Connect

    Alleman, Teresa L.

    2015-07-27

    ASTM D5798 sets the specifications for Ethanol Flex Fuel, which currently permits between 51 volume percent (vol%) and 83 vol% ethanol. The vapor pressure varies seasonally and geographically and is divided into four distinct classes to ensure year-round driveability. This project is the first survey of Ethanol Flex Fuel since these specification changes were made to Specification D5798.

  7. 12 CFR 742.2 - Criteria to qualify for RegFlex designation.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Criteria to qualify for RegFlex designation. 742.2 Section 742.2 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS REGULATORY FLEXIBILITY PROGRAM § 742.2 Criteria to qualify for RegFlex designation. (a) Automatic qualification. A credit union...

  8. Uniqueness of place: uniqueness of models. The FLEX modelling approach

    NASA Astrophysics Data System (ADS)

    Fenicia, F.; Savenije, H. H. G.; Wrede, S.; Schoups, G.; Pfister, L.

    2009-04-01

    The current practice in hydrological modelling is to make use of model structures that are fixed and a-priori defined. However, for a model to reflect uniqueness of place while maintaining parsimony, it is necessary to be flexible in its architecture. We have developed a new approach for the development and testing of hydrological models, named the FLEX approach. This approach allows the formulation of alternative model structures that vary in configuration and complexity, and uses an objective method for testing and comparing model performance. We have tested this approach on three headwater catchments in Luxembourg with marked differences in hydrological response, where we have generated 15 alternative model structures. Each of the three catchments is best represented by a different model architecture. Our results clearly show that uniqueness of place necessarily leads to uniqueness of models.

  9. Fabrication of Flex Joint Utilizing Additively Manufactured Parts

    NASA Technical Reports Server (NTRS)

    Eddleman, David; Richard, Jim

    2015-01-01

    The Selective Laser Melting (SLM) manufacturing technique has been utilized in the manufacture of a flex joint typical of those found in rocket engine and main propulsion system ducting. The SLM process allowed for the combination of parts that are typically machined separately and welded together. This resulted in roughly a 65% reduction of the total number of parts, roughly 70% reduction in the total number of welds, and an estimated 60% reduction in the number of machining operations. The majority of the new design was in three SLM pieces. These pieces, as well as a few traditionally fabricated parts, were assembled into a complete unit, which has been pressure tested. The design and planned cryogenic testing of the unit will be presented.

  10. FLEX: A Decisive Step Forward in NASA's Combustion Research Program

    NASA Technical Reports Server (NTRS)

    Hickman, John M.; Dietrich, Daniel L.; Hicks, Michael C.; Nayagam, Vedha; Stocker, Dennis

    2012-01-01

    Stemming from the need to prevent, detect and suppress on-board spacecraft fires, the NASA microgravity combustion research program has grown to include fundamental research. From early experiment, we have known that flames behave differently in microgravity, and this environment would provide an ideal laboratory for refining many of the long held principals of combustion science. A microgravity environment can provide direct observation of phenomena that cannot be observed on Earth. Through the years, from precursor work performed in drop towers leading to experiments on the International Space Station (ISS), discoveries have been made about the nature of combustion in low gravity environments. These discoveries have uncovered new phenomena and shed a light on many of the fundamental phenomena that drive combustion processes. This paper discusses the NASA microgravity combustion research program taking place in the ISS Combustion Integrated Rack, its various current and planned experiments, and the early results from the Flame Extinguishment (FLEX) Experiment.

  11. FLEX: A Modular Software Architecture for Flight License Exam

    NASA Astrophysics Data System (ADS)

    Arsan, Taner; Saka, Hamit Emre; Sahin, Ceyhun

    This paper is about the design and implementation of an examination system based on World Wide Web. It is called FLEX-Flight License Exam Software. We designed and implemented flexible and modular software architecture. The implemented system has basic specifications such as appending questions in system, building exams with these appended questions and making students to take these exams. There are three different types of users with different authorizations. These are system administrator, operators and students. System administrator operates and maintains the system, and also audits the system integrity. The system administrator can not be able to change the result of exams and can not take an exam. Operator module includes instructors. Operators have some privileges such as preparing exams, entering questions, changing the existing questions and etc. Students can log on the system and can be accessed to exams by a certain URL. The other characteristic of our system is that operators and system administrator are not able to delete questions due to the security problems. Exam questions can be inserted on their topics and lectures in the database. Thus; operators and system administrator can easily choose questions. When all these are taken into consideration, FLEX software provides opportunities to many students to take exams at the same time in safe, reliable and user friendly conditions. It is also reliable examination system for the authorized aviation administration companies. Web development platform - LAMP; Linux, Apache web server, MySQL, Object-oriented scripting Language - PHP are used for developing the system and page structures are developed by Content Management System - CMS.

  12. Advances in Current Rating Techniques for Flexible Printed Circuits

    NASA Technical Reports Server (NTRS)

    Hayes, Ron

    2014-01-01

    Twist Capsule Assemblies are power transfer devices commonly used in spacecraft mechanisms that require electrical signals to be passed across a rotating interface. Flexible printed circuits (flex tapes, see Figure 2) are used to carry the electrical signals in these devices. Determining the current rating for a given trace (conductor) size can be challenging. Because of the thermal conditions present in this environment the most appropriate approach is to assume that the only means by which heat is removed from the trace is thru the conductor itself, so that when the flex tape is long the temperature rise in the trace can be extreme. While this technique represents a worst-case thermal situation that yields conservative current ratings, this conservatism may lead to overly cautious designs when not all traces are used at their full rated capacity. A better understanding of how individual traces behave when they are not all in use is the goal of this research. In the testing done in support of this paper, a representative flex tape used for a flight Solar Array Drive Assembly (SADA) application was tested by energizing individual traces (conductors in the tape) in a vacuum chamber and the temperatures of the tape measured using both fine-gauge thermocouples and infrared thermographic imaging. We find that traditional derating schemes used for bundles of wires do not apply for the configuration tested. We also determine that single active traces located in the center of a flex tape operate at lower temperatures than those on the outside edges.

  13. MULTIPLIER CIRCUIT

    DOEpatents

    Thomas, R.E.

    1959-01-20

    An electronic circuit is presented for automatically computing the product of two selected variables by multiplying the voltage pulses proportional to the variables. The multiplier circuit has a plurality of parallel resistors of predetermined values connected through separate gate circults between a first input and the output terminal. One voltage pulse is applied to thc flrst input while the second voltage pulse is applied to control circuitry for the respective gate circuits. Thc magnitude of the second voltage pulse selects the resistors upon which the first voltage pulse is imprcssed, whereby the resultant output voltage is proportional to the product of the input voltage pulses

  14. GATING CIRCUITS

    DOEpatents

    Merrill, L.C.

    1958-10-14

    Control circuits for vacuum tubes are described, and a binary counter having an improved trigger circuit is reported. The salient feature of the binary counter is the application of the input signal to the cathode of each of two vacuum tubes through separate capacitors and the connection of each cathode to ground through separate diodes. The control of the binary counter is achieved in this manner without special pulse shaping of the input signal. A further advantage of the circuit is the simplicity and minimum nuruber of components required, making its use particularly desirable in computer machines.

  15. TRIPPING CIRCUIT

    DOEpatents

    Lees, G.W.; McCormick, E.D.

    1962-05-22

    A tripping circuit employing a magnetic amplifier for tripping a reactor in response to power level, period, or instrument failure is described. A reference winding and signal winding are wound in opposite directions on the core. Current from an ion chamber passes through both windings. If the current increases at too fast a rate, a shunt circuit bypasses one or the windings and the amplifier output reverses polarity. (AEC)

  16. The force on the flex: Global parallelism and portability

    NASA Technical Reports Server (NTRS)

    Jordan, H. F.

    1986-01-01

    A parallel programming methodology, called the force, supports the construction of programs to be executed in parallel by an unspecified, but potentially large, number of processes. The methodology was originally developed on a pipelined, shared memory multiprocessor, the Denelcor HEP, and embodies the primitive operations of the force in a set of macros which expand into multiprocessor Fortran code. A small set of primitives is sufficient to write large parallel programs, and the system has been used to produce 10,000 line programs in computational fluid dynamics. The level of complexity of the force primitives is intermediate. It is high enough to mask detailed architectural differences between multiprocessors but low enough to give the user control over performance. The system is being ported to a medium scale multiprocessor, the Flex/32, which is a 20 processor system with a mixture of shared and local memory. Memory organization and the type of processor synchronization supported by the hardware on the two machines lead to some differences in efficient implementations of the force primitives, but the user interface remains the same. An initial implementation was done by retargeting the macros to Flexible Computer Corporation's ConCurrent C language. Subsequently, the macros were caused to directly produce the system calls which form the basis for ConCurrent C. The implementation of the Fortran based system is in step with Flexible Computer Corporations's implementation of a Fortran system in the parallel environment.

  17. Watching individual molecules flex within lipid membranes using SERS

    PubMed Central

    Taylor, Richard W.; Benz, Felix; Sigle, Daniel O.; Bowman, Richard W.; Bao, Peng; Roth, Johannes S.; Heath, George R.; Evans, Stephen D.; Baumberg, Jeremy J.

    2014-01-01

    Interrogating individual molecules within bio-membranes is key to deepening our understanding of biological processes essential for life. Using Raman spectroscopy to map molecular vibrations is ideal to non-destructively ‘fingerprint’ biomolecules for dynamic information on their molecular structure, composition and conformation. Such tag-free tracking of molecules within lipid bio-membranes can directly connect structure and function. In this paper, stable co-assembly with gold nano-components in a ‘nanoparticle-on-mirror’ geometry strongly enhances the local optical field and reduces the volume probed to a few nm3, enabling repeated measurements for many tens of minutes on the same molecules. The intense gap plasmons are assembled around model bio-membranes providing molecular identification of the diffusing lipids. Our experiments clearly evidence measurement of individual lipids flexing through telltale rapid correlated vibrational shifts and intensity fluctuations in the Raman spectrum. These track molecules that undergo bending and conformational changes within the probe volume, through their interactions with the environment. This technique allows for in situ high-speed single-molecule investigations of the molecules embedded within lipid bio-membranes. It thus offers a new way to investigate the hidden dynamics of cell membranes important to a myriad of life processes. PMID:25113088

  18. Flexible tab-assisted control concept (FlexTAC)

    NASA Astrophysics Data System (ADS)

    Nguyen, Thang D.; Carpenter, Bernie F.; Hall, Jeffrey

    2001-06-01

    In late 1997 under ONR and DARPA funding members of the SAMPSON Marine Naval Team (Naval Surface Warfare Center, Lockeed Martin and General Dynamics Electric Boat) began investigating the benefits of the tab assisted control (TAC) concept for underwater control surfaces. Results of water tunnel tests conducted in 1998 indicated that the addition of a small trailing-edge tab, typically 10% of the mean chord of the entire control surface structure, vastly enhances the versatility of the control surface system. Depending on the orientation of the tab with respect to the primary control surface (flap) this tab may be used to significantly modify lift, reduce torque, and increase maneuvering capabilities. In 1999 a plan was established to actuate the tab with Shape Memory Alloy (SMA) actuators as a first step towards development of a continuously compliant or flexible control surface similar to that demonstrated in the DARPA Smart Vortex Leveraging Tab (SVLT) program. Testing of a SMA-actuated TAC device occurred late summer 2000. This paper presents a summary of these activities as well as current plant to test and evaluate the FlexTAC (Flexible Tab Assisted Control) concept, which replaces the tab with a continuously compliant trailing edge.

  19. MULTIPLIER CIRCUIT

    DOEpatents

    Chase, R.L.

    1963-05-01

    An electronic fast multiplier circuit utilizing a transistor controlled voltage divider network is presented. The multiplier includes a stepped potentiometer in which solid state or transistor switches are substituted for mechanical wipers in order to obtain electronic switching that is extremely fast as compared to the usual servo-driven mechanical wipers. While this multiplier circuit operates as an approximation and in steps to obtain a voltage that is the product of two input voltages, any desired degree of accuracy can be obtained with the proper number of increments and adjustment of parameters. (AEC)

  20. Chip-on-flex with 5-micron features

    NASA Astrophysics Data System (ADS)

    Salmon, Peter C.

    2003-01-01

    A new module packaging method is proposed for electronic systems comprising a motherboard and integrated circuit (IC) chips. Pitches of 10 microns for conductive traces, and 100 microns for bonding pads are achievable. The enabling technology is glass panel manufacture, using equipment and techniques similar to those employed for fabricating liquid crystal display (LCD) panels. Flexible circuits are produced on a glass carrier using a release layer, and the carrier is removed after most of the processing is complete. IC chips are stud bumped and flip chip bonded to wells filled with solder, provided on the flexible circuit. The fabrication density achievable with wafer level packaging (WLP) using silicon wafers is substantially more than is needed for module packaging, as described herein. It is possible to provide WLP performance on glass at a much lower cost. The conductor features on glass are fine enough for the most demanding packaging and assembly techniques. The lowered cost of glass applies to the interconnection circuit plus assembly, test and rework. A test method called Tester-On-Board (TOB) is proposed, employing special-purpose test chips that are directly mounted in the system and mimic the capabilities of external testers. Methods for hermetic sealing, electromagnetic screening, and high-density off-board connections are also proposed.

  1. Picosecond laser cutting and drilling of thin flex glass

    NASA Astrophysics Data System (ADS)

    Wlodarczyk, Krystian L.; Brunton, Adam; Rumsby, Phil; Hand, Duncan P.

    2016-03-01

    We investigate the feasibility of cutting and drilling thin flex glass (TFG) substrates using a picosecond laser operating at wavelengths of 1030 nm, 515 nm and 343 nm. 50 μm and 100 μm thick AF32®Eco Thin Glass (Schott AG) sheets are used. The laser processing parameters such as the wavelength, pulse energy, pulse repetition frequency, scan speed and the number of laser passes which are necessary to perform through a cut or to drill a borehole in the TFG substrate are studied in detail. Our results show that the highest effective cutting speeds (220 mm/s for a 50 μm thick TFG substrate and 74 mm/s for a 100 μm thick TFG substrate) are obtained with the 1030 nm wavelength, whereas the 343 nm wavelength provides the best quality cuts. The 515 nm wavelength, meanwhile, can be used to provide relatively good laser cut quality with heat affected zones (HAZ) of <25 μm for 50 μm TFG and <40 μm for 100 μm TFG with cutting speeds of 100 mm/s and 28.5 mm/s, respectively. The 343 nm and 515 nm wavelengths can also be used for drilling micro-holes (with inlet diameters of ⩽75 μm) in the 100 μm TFG substrate with speeds of up to 2 holes per second (using 343 nm) and 8 holes per second (using 515 nm). Optical microscope and SEM images of the cuts and micro-holes are presented.

  2. Circuit Training.

    ERIC Educational Resources Information Center

    Nelson, Jane B.

    1998-01-01

    Describes a research-based activity for high school physics students in which they build an LC circuit and find its resonant frequency of oscillation using an oscilloscope. Includes a diagram of the apparatus and an explanation of the procedures. (DDR)

  3. FlexAID: Revisiting Docking on Non-Native-Complex Structures.

    PubMed

    Gaudreault, Francis; Najmanovich, Rafael J

    2015-07-27

    Small-molecule protein docking is an essential tool in drug design and to understand molecular recognition. In the present work we introduce FlexAID, a small-molecule docking algorithm that accounts for target side-chain flexibility and utilizes a soft scoring function, i.e. one that is not highly dependent on specific geometric criteria, based on surface complementarity. The pairwise energy parameters were derived from a large dataset of true positive poses and negative decoys from the PDBbind database through an iterative process using Monte Carlo simulations. The prediction of binding poses is tested using the widely used Astex dataset as well as the HAP2 dataset, while performance in virtual screening is evaluated using a subset of the DUD dataset. We compare FlexAID to AutoDock Vina, FlexX, and rDock in an extensive number of scenarios to understand the strengths and limitations of the different programs as well as to reported results for Glide, GOLD, and DOCK6 where applicable. The most relevant among these scenarios is that of docking on flexible non-native-complex structures where as is the case in reality, the target conformation in the bound form is not known a priori. We demonstrate that FlexAID, unlike other programs, is robust against increasing structural variability. FlexAID obtains equivalent sampling success as GOLD and performs better than AutoDock Vina or FlexX in all scenarios against non-native-complex structures. FlexAID is better than rDock when there is at least one critical side-chain movement required upon ligand binding. In virtual screening, FlexAID results are lower on average than those of AutoDock Vina and rDock. The higher accuracy in flexible targets where critical movements are required, intuitive PyMOL-integrated graphical user interface and free source code as well as precompiled executables for Windows, Linux, and Mac OS make FlexAID a welcome addition to the arsenal of existing small-molecule protein docking methods. PMID

  4. Urethane/Silicone Adhesives for Bonding Flexing Metal Parts

    NASA Technical Reports Server (NTRS)

    Edwards, Paul D.

    2004-01-01

    Adhesives that are blends of commercially available urethane and silicone adhesives have been found to be useful for bonding metal parts that flex somewhat during use. These urethane/silicone adhesives are formulated for the specific metal parts to be bonded. The bonds formed by these adhesives have peel and shear strengths greater than those of bonds formed by double-sided tapes and by other adhesives, including epoxies and neat silicones. In addition, unlike the bonds formed by epoxies, the bonds formed by these adhesives retain flexibility. In the initial application for which the urethane/silicone adhesives were devised, there was a need to bond spring rings, which provide longitudinal rigidity for inflatable satellite booms, with the blades that provide the booms axial strength. The problem was to make the bonds withstand the stresses, associated with differences in curvature between the bonded parts, that arose when the booms were deflated and the springs were compressed. In experiments using single adhesives (that is, not the urethane/ silicone blends), the bonds were broken and, in each experiment, it was found that the adhesive bonded well with either the ring or with the blade, but not both. After numerous experiments, the adhesive that bonded best with the rings and the adhesive that bonded best with the blades were identified. These adhesives were then blended and, as expected, the blend bonded well with both the rings and the blades. The two adhesives are Kalex (or equivalent) high-shear-strength urethane and Dow Corning 732 (or equivalent) silicone. The nominal mixture ratio is 5 volume parts of the urethane per 1 volume part of the silicone. Increasing the proportion of silicone makes the bond weaker but more flexible, and decreasing the proportion of silicone makes the bond stronger but more brittle. The urethane/silicone blend must be prepared and used quickly because of the limited working time of the urethane: The precursor of the urethane

  5. Flex-gear power transmission system for transmitting EMF between Sun and ring gears

    NASA Technical Reports Server (NTRS)

    Vranish, John M. (Inventor)

    1994-01-01

    A plurality of flexible cylindrical members, termed flex-gears and having gear tooth type perimeters are located in an annular space between two concentric rotating gear members, one an inner gear member and the other an outer ring gear member, both of which have mutually facing toothed surfaces which engage the flex-gears. The flex-gears rotate and orbit around the annular space as planetary gears when the inner and outer gear members rotate with respect to one another. Pairs of these elements located in two mutually parallel planes and separated by insulators provide two electrical conductor paths across which an electrical signal source, AC or DC, can be connected and coupled to an electrical device. Alternatively, one set of elements including outer gears segmented into mutually insulated semicircles and inner gears segmented into mutually insulated quadrants can be used.

  6. Flex-gear power transmission system for transmitting EMF between Sun and ring gears

    NASA Astrophysics Data System (ADS)

    Vranish, John M.

    1994-10-01

    A plurality of flexible cylindrical members, termed flex-gears and having gear tooth type perimeters are located in an annular space between two concentric rotating gear members, one an inner gear member and the other an outer ring gear member, both of which have mutually facing toothed surfaces which engage the flex-gears. The flex-gears rotate and orbit around the annular space as planetary gears when the inner and outer gear members rotate with respect to one another. Pairs of these elements located in two mutually parallel planes and separated by insulators provide two electrical conductor paths across which an electrical signal source, AC or DC, can be connected and coupled to an electrical device. Alternatively, one set of elements including outer gears segmented into mutually insulated semicircles and inner gears segmented into mutually insulated quadrants can be used.

  7. Circuit Connectors

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The U-shaped wire devices in the upper photo are Digi-Klipsm; aids to compact packaging of electrical and electronic devices. They serve as connectors linking the circuitry of one circuit board with another in multi-board systems. Digi-Klips were originally developed for Goddard Space Flight Center to meet a need for lightweight, reliable connectors to replace hand-wired connections formerly used in spacecraft. They are made of beryllium copper wire, noted for its excellent conductivity and its spring-like properties, which assure solid electrical contact over a long period of time.

  8. An object simulation model for modeling hypothetical disease epidemics – EpiFlex

    PubMed Central

    Hanley, Brian

    2006-01-01

    Background EpiFlex is a flexible, easy to use computer model for a single computer, intended to be operated by one user who need not be an expert. Its purpose is to study in-silico the epidemic behavior of a wide variety of diseases, both known and theoretical, by simulating their spread at the level of individuals contracting and infecting others. To understand the system fully, this paper must be read together in conjunction with study of the software and its results. EpiFlex is evaluated using results from modeling influenza A epidemics and comparing them with a variety of field data sources and other types of modeling. EpiFlex is an object-oriented Monte Carlo system, allocating entities to correspond to individuals, disease vectors, diseases, and the locations that hosts may inhabit. EpiFlex defines eight different contact types available for a disease. Contacts occur inside locations within the model. Populations are composed of demographic groups, each of which has a cycle of movement between locations. Within locations, superspreading is defined by skewing of contact distributions. Results EpiFlex indicates three phenomena of interest for public health: (1) R0 is variable, and the smaller the population, the larger the infected fraction within that population will be; (2) significant compression/synchronization between cities by a factor of roughly 2 occurs between the early incubation phase of a multi-city epidemic and the major manifestation phase; (3) if better true morbidity data were available, more asymptomatic hosts would be seen to spread disease than we currently believe is the case for influenza. These results suggest that field research to study such phenomena, while expensive, should be worthwhile. Conclusion Since EpiFlex shows all stages of disease progression, detailed insight into the progress of epidemics is possible. EpiFlex shows the characteristic multimodality and apparently random variation characteristic of real world data, but does

  9. An Effective GA-Based Scheduling Algorithm for FlexRay Systems

    NASA Astrophysics Data System (ADS)

    Ding, Shan; Tomiyama, Hiroyuki; Takada, Hiroaki

    An advanced communication system, the FlexRay system, has been developed for future automotive applications. It consists of time-triggered clusters, such as drive-by-wire in cars, in order to meet different requirements and constraints between various sensors, processors, and actuators. In this paper, an approach to static scheduling for FlexRay systems is proposed. Our experimental results show that the proposed scheduling method significantly reduces up to 36.3% of the network traffic compared with a past approach.

  10. Detailed Results from the Flame Extinguishment Experiment (FLEX) March 2009 to December 2011

    NASA Technical Reports Server (NTRS)

    Dietrich, Daniel L.; Ferkul, Paul V.; Bryg, Victoria M.; Nayagam, M. Vedha; Hicks, Michael C.; Williams, Forman A.; Dryer, Frederick L.; Shaw, Benjamin D.; Choi, Mun Y.; Avedisian, C. Thomas

    2015-01-01

    The Flame Extinguishment Experiment (FLEX) program is a continuing set of experiments on droplet combustion, performed employing the Multi-User Droplet Combustion Apparatus (MDCA), inside the chamber of the Combustion Integrated Rack (CIR), which is located in the Destiny module of the International Space Station (ISS). This report describes the experimental hardware, the diagnostic equipment, the experimental procedures, and the methods of data analysis for FLEX. It also presents the results of the first 284 tests performed. The intent is not to interpret the experimental results but rather to make them available to the entire scientific community for possible future interpretations.

  11. A generic multi-flex-body dynamics, controls simulation tool for space station

    NASA Technical Reports Server (NTRS)

    London, Ken W.; Lee, John F.; Singh, Ramen P.; Schubele, Buddy

    1991-01-01

    An order (n) multiflex body Space Station simulation tool is introduced. The flex multibody modeling is generic enough to model all phases of Space Station from build up through to Assembly Complete configuration and beyond. Multibody subsystems such as the Mobile Servicing System (MSS) undergoing a prescribed translation and rotation are also allowed. The software includes aerodynamic, gravity gradient, and magnetic field models. User defined controllers can be discrete or continuous. Extensive preprocessing of 'body by body' NASTRAN flex data is built in. A significant aspect, too, is the integrated controls design capability which includes model reduction and analytic linearization.

  12. Introducing a domain flexing function in the Jiles-Atherton hysteresis model

    NASA Astrophysics Data System (ADS)

    Miljavec, Damijan; Zidarič, Bogomir

    The Jiles-Atherton hysteresis model (J-A model) exhibits a certain unphysical behavior when magnetic excitation reaches or reverses from the extremity of the hysteresis loop. Introducing a domain flexing function, coherent with the magnetic excitation level, improves accuracy of the J-A hysteresis model and at the same time prevents its unphysical behavior. Moreover, applying this function also improves representation of inner (lower excitation level) hysteresis loops. Implementation of magnetic excitation dependence in the domain flexing function adds a valuable parameter to the J-A original model on the way towards its further optimization. In the proposed hysteresis model, genetic algorithms are used in parameters optimization.

  13. LOGIC CIRCUIT

    DOEpatents

    Strong, G.H.; Faught, M.L.

    1963-12-24

    A device for safety rod counting in a nuclear reactor is described. A Wheatstone bridge circuit is adapted to prevent de-energizing the hopper coils of a ball backup system if safety rods, sufficient in total control effect, properly enter the reactor core to effect shut down. A plurality of resistances form one arm of the bridge, each resistance being associated with a particular safety rod and weighted in value according to the control effect of the particular safety rod. Switching means are used to switch each of the resistances in and out of the bridge circuit responsive to the presence of a particular safety rod in its effective position in the reactor core and responsive to the attainment of a predetermined velocity by a particular safety rod enroute to its effective position. The bridge is unbalanced in one direction during normal reactor operation prior to the generation of a scram signal and the switching means and resistances are adapted to unbalance the bridge in the opposite direction if the safety rods produce a predetermined amount of control effect in response to the scram signal. The bridge unbalance reversal is then utilized to prevent the actuation of the ball backup system, or, conversely, a failure of the safety rods to produce the predetermined effect produces no unbalance reversal and the ball backup system is actuated. (AEC)

  14. Evaluation of Flexibility Under "No Child Left Behind": Volume III--The Rural Education Achievement Program (REAP Flex)

    ERIC Educational Resources Information Center

    Christensen, Gayle S.; Amerikaner, Ary; Klasik, Daniel; Cohodes, Sarah

    2007-01-01

    This study focuses on flexibility provisions in the Rural Education Achievement Program (REAP) provision of NCLB. Specifically, it addresses REAP Flex, a program that allows rural districts additional control over how to spend portions of their federal funding. REAP Flex is part of a series of NCLB flexibility initiatives aimed at rural schools.…

  15. FLEX+DMFT approach to the d -wave superconducting phase diagram of the two-dimensional Hubbard model

    NASA Astrophysics Data System (ADS)

    Kitatani, Motoharu; Tsuji, Naoto; Aoki, Hideo

    2015-08-01

    The dynamical mean-field theory (DMFT) combined with the fluctuation exchange (FLEX) method, namely, FLEX+DMFT, is an approach for correlated electron systems to incorporate both local and nonlocal long-range correlations in a self-consistent manner. We formulate FLEX+DMFT in a systematic way starting from a Luttinger-Ward functional, and apply it to study the d -wave superconductivity in the two-dimensional repulsive Hubbard model. The critical temperature (Tc) curve obtained in the FLEX+DMFT exhibits a dome structure as a function of the filling, which has not been clearly observed in the FLEX approach alone. We trace back the origin of the dome to the local vertex correction from DMFT that renders a filling dependence in the FLEX self-energy. We compare the results with those of GW+DMFT, where the Tc-dome structure is qualitatively reproduced due to the same vertex correction effect, but a crucial difference from FLEX+DMFT is that Tc is always estimated below the Néel temperature in GW+DMFT. The single-particle spectral function obtained with FLEX+DMFT exhibits a double-peak structure as a precursor of the Hubbard bands at temperatures above Tc.

  16. Effect of weed management on quality of Roundup Ready Flex cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Roundup Ready Flex cotton will be commercially available to growers in 2006. Alabama growers need information about this new technology under their growing conditions and weeds. Field trials were conducted at the Prattville Experiment Field, Prattville, AL and the Field Crops Unit, Shorter, AL in 20...

  17. USER'S GUIDE TO FLEXIBLE MEMBRANE LINER ADVISORY EXPERT SYSTEM: FLEX VERSION 3.0

    EPA Science Inventory

    The guide is a user manual for the Flexible Membrane Liner Advisory Expert System (FLEX). The system assists in determining if a proposed synthetic liner material will be chemically resistant to a proposed or anticipated leachate from a hazardous waste land disposal site. More sp...

  18. Assessing the operational life of flexible printed boards intended for continuous flexing applications : a case study.

    SciTech Connect

    Beck, David Franklin

    2011-01-01

    Through the vehicle of a case study, this paper describes in detail how the guidance found in the suite of IPC (Association Connecting Electronics Industries) publications can be applied to develop a high level of design assurance that flexible printed boards intended for continuous flexing applications will satisfy specified lifetime requirements.

  19. FLEX: AN EXPERT SYSTEM FOR REVIEWING THE CHEMICAL RESISTANCE OF FLEXIBLE MEMBRANE LINERS FOR WASTE MANAGEMENT

    EPA Science Inventory

    A computerized, expert system (FLEX) has been developed that will assess the chemical resistance of flexible membrane liners (FML) used at waste management facilities. hese FML's must be chemically resistant to the waste, its leachates, or both. o demonstrate chemical resistancy,...

  20. Measurement of Flexed Posture for Flexible Mono-Tread Mobile Track

    NASA Astrophysics Data System (ADS)

    Kinugasa, Tetsuya; Akagi, Tetsuya; Ishii, Kuniaki; Haji, Takafumi; Yoshida, Koji; Amano, Hisanori; Hayashi, Ryota; Tokuda, Kenichi; Iribe, Masatsugu; Osuka, Koichi

    We have proposed Flexible Mono-tread mobile Track (FMT) as a mobile mechanism on rough terrain for rescue activity, environmental investigation and planetary explorer, etc. Generally speaking, one has to teleoperate robots under invisible condition. In order to operate the robots skillfully, it is necessary to detect not only condition around the robots and its position but also posture of the robots at any time. Since flexed posture of FMT decides turning radius and direction, it is important to know its posture. FMT has vertebral structure composed of vertebrae as rigid body and intervertebral disks made by flexible devices such as rubber cylinder and spring. Since the intervertebral disks flex in three dimension, traditional sensors such as potentiometers, rotary encoders and range finders can hardly use for measurement of its deformation. The purpose of the paper, therefore, is to measure flexed posture of FMT using a novel flexible displacement sensor. We prove that the flexed posture of FMT with five intervertebral disks can be detected through experiment.

  1. USER'S GUIDE TO FLEXIBLE MEMBRANE LINER ADVISORY EXPERT SYSTEM: FLEX VERSION 3.0

    EPA Science Inventory

    A user manual for the Flexible Membrane Liner Advisory Expert System (FLEX). his system assists in determining if a proposed synthetic liner material will be chemically resistant to a proposed or anticipated leachate from a hazardous waste land disposal site. ore specifically, it...

  2. Open-source modular solutions for flexural isostasy: gFlex v1.0

    NASA Astrophysics Data System (ADS)

    Wickert, A. D.

    2016-03-01

    Isostasy is one of the oldest and most widely applied concepts in the geosciences, but the geoscientific community lacks a coherent, easy-to-use tool to simulate flexure of a realistic (i.e., laterally heterogeneous) lithosphere under an arbitrary set of surface loads. Such a model is needed for studies of mountain building, sedimentary basin formation, glaciation, sea-level change, and other tectonic, geodynamic, and surface processes. Here I present gFlex (for GNU flexure), an open-source model that can produce analytical and finite difference solutions for lithospheric flexure in one (profile) and two (map view) dimensions. To simulate the flexural isostatic response to an imposed load, it can be used by itself or within GRASS GIS for better integration with field data. gFlex is also a component with the Community Surface Dynamics Modeling System (CSDMS) and Landlab modeling frameworks for coupling with a wide range of Earth-surface-related models, and can be coupled to additional models within Python scripts. As an example of this in-script coupling, I simulate the effects of spatially variable lithospheric thickness on a modeled Iceland ice cap. Finite difference solutions in gFlex can use any of five types of boundary conditions: 0-displacement, 0-slope (i.e., clamped); 0-slope, 0-shear; 0-moment, 0-shear (i.e., broken plate); mirror symmetry; and periodic. Typical calculations with gFlex require ≪ 1 s to ˜ 1 min on a personal laptop computer. These characteristics - multiple ways to run the model, multiple solution methods, multiple boundary conditions, and short compute time - make gFlex an effective tool for flexural isostatic modeling across the geosciences.

  3. Open-source modular solutions for flexural isostasy: gFlex v1.0

    NASA Astrophysics Data System (ADS)

    Wickert, A. D.

    2015-06-01

    Isostasy is one of the oldest and most widely applied concepts in the geosciences, but the geoscientific community lacks a coherent, easy-to-use tool to simulate flexure of a realistic (i.e. laterally heterogeneous) lithosphere under an arbitrary set of surface loads. Such a model is needed for studies of mountain-building, sedimentary basin formation, glaciation, sea-level change, and other tectonic, geodynamic, and surface processes. Here I present gFlex, an open-source model that can produce analytical and finite difference solutions for lithospheric flexure in one (profile) and two (map view) dimensions. To simulate the flexural isostatic response to an imposed load, it can be used by itself or within GRASS GIS for better integration with field data. gFlex is also a component with the Community Surface Dynamics Modeling System (CSDMS) and Landlab modeling frameworks for coupling with a wide range of Earth-surface-related models, and can be coupled to additional models within Python scripts. As an example of this in-script coupling, I simulate the effects of spatially variable lithospheric thickness on a modeled Iceland ice cap. Finite difference solutions in gFlex can use any of five types of boundary conditions: 0-displacement, 0-slope (i.e. clamped); 0-slope, 0-shear; 0-moment, 0-shear (i.e. broken plate); mirror symmetry; and periodic. Typical calculations with gFlex require ≪ 1s to ~1 min on a personal laptop computer. These characteristics - multiple ways to run the model, multiple solution methods, multiple boundary conditions, and short compute time - make gFlex an effective tool for flexural isostatic modeling across the geosciences.

  4. Commutation circuit for an HVDC circuit breaker

    DOEpatents

    Premerlani, William J.

    1981-01-01

    A commutation circuit for a high voltage DC circuit breaker incorporates a resistor capacitor combination and a charging circuit connected to the main breaker, such that a commutating capacitor is discharged in opposition to the load current to force the current in an arc after breaker opening to zero to facilitate arc interruption. In a particular embodiment, a normally open commutating circuit is connected across the contacts of a main DC circuit breaker to absorb the inductive system energy trapped by breaker opening and to limit recovery voltages to a level tolerable by the commutating circuit components.

  5. Commutation circuit for an HVDC circuit breaker

    DOEpatents

    Premerlani, W.J.

    1981-11-10

    A commutation circuit for a high voltage DC circuit breaker incorporates a resistor capacitor combination and a charging circuit connected to the main breaker, such that a commutating capacitor is discharged in opposition to the load current to force the current in an arc after breaker opening to zero to facilitate arc interruption. In a particular embodiment, a normally open commutating circuit is connected across the contacts of a main DC circuit breaker to absorb the inductive system energy trapped by breaker opening and to limit recovery voltages to a level tolerable by the commutating circuit components. 13 figs.

  6. User assessment of Norditropin NordiFlex®, a new prefilled growth hormone pen: a Phase IV multicenter prospective study

    PubMed Central

    Tauber, Maithé; Jaquet, Delphine; Jesuran-Perelroizen, Monique; Petrus, Marc; Bertrand, Anne Marie; Coutant, Regis

    2013-01-01

    Background/aim In growth disorders, ensuring long-term growth hormone therapy (GHT) remains a challenge that might compromise the clinical outcome. Consequently, strategies aiming at alleviating the burden of daily injection might improve the treatment benefit. The study reported here was performed to assess the ease of use of Norditropin NordiFlex® (Novo Nordisk, Princeton, NJ, USA) compared with that of the devices previously used in children treated with GHT with recombinant somatropin. Methods This Phase IV prospective, multicenter, open-label study was conducted in France. All patients received Norditropin NordiFlex for 6 weeks. Oral questionnaires were administered by the physician to the patients and/or the parents at inclusion and at the final visit. Results This study included 103 patients aged between 6 and 17 years. The patients assessed Norditropin NordiFlex as significantly easier to use than their previous device (median value = 7.5, P < 0.001). Almost three-quarters of patients (64.4%) preferred Norditropin NordiFlex to their previous device. Among physicians and nurses, 73% assessed Norditropin NordiFlex training as “very easy” and 26% as “easy.” Norditropin NordiFlex improved patient autonomy, with 41% of patients able to self-inject the treatment. Conclusion This study has shown that Norditropin NordiFlex is reliable, safe, and easy to use and most study patients preferred it to their previous device. These characteristics may improve the adherence to GHT. PMID:23737664

  7. A simple tachometer circuit

    NASA Technical Reports Server (NTRS)

    Dimeff, J.

    1972-01-01

    Electric circuit to measure frequency of repetitive sinusoidal or rectangular wave is presented. Components of electric circuit and method of operation are explained. Application of circuit as tachometer for automobile is discussed.

  8. Photomultiplier blanking circuit

    NASA Technical Reports Server (NTRS)

    Mcclenahan, J. O.

    1972-01-01

    Circuit for protecting photomultiplier equipment from current surges which occur when exposed to brilliant illumination is discussed. Components of circuit and details of operation are provided. Circuit diagram to show action of blanking pulse on zener diode is included.

  9. Electronics box having internal circuit cards interconnected to external connectors sans motherboard

    NASA Technical Reports Server (NTRS)

    Hockett, John E. (Inventor)

    2005-01-01

    An electronics chassis box includes a pair of opposing sidewalls, a pair of opposing end walls, a bottom surface, a top cover, and ring connectors assemblies mounted in selective ones of the walls of the electronic box. Boss members extend from the bottom surface at different heights upon which circuit cards are mounted in spatial relationship to each other. A flex interconnect substantially reduces and generally eliminates the need of a motherboard by interconnecting the circuit cards to one another and to external connectors mounted within the ring connector assemblies.

  10. Technical evaluation and assessment of CNG/LPG bi-fuel and flex-fuel vehicle viability

    SciTech Connect

    Sinor, J E

    1994-05-01

    This report compares vehicles using compressed natural gas (CNG), liquefied petroleum gas (LPG), and combinations of the two in bi-fuel or flex-fuel configurations. Evidence shows that environmental and energy advantages can be gained by replacing two-fuel CNG/gasoline vehicles with two-fuel or flex-fuel systems to be economically competitive, it is necessary to develop a universal CNG/LPG pressure-regulator-injector and engine control module to switch from one tank to the other. For flex-fuel CNG/LPG designs, appropriate composition sensors, refueling pumps, fuel tanks, and vaporizers are necessary.

  11. [Effects of application resistive and flex resistance to breath in training sportsmen].

    PubMed

    Gorbaneva, E P; Solopov, A I; Vlasov, A A; Voskresenskiĭ, S A

    2010-01-01

    Research on studying influence of a rate of muscular training in conditions of additional aerodynamic and flex resistance to breath on a level of physical working capacity, aerobic productivity and a functional condition of system of breath is executed. It is shown, that regular muscular training on a background of use of the dosed out breath with increased aerodynamic and flex resistance to respiratory stream and respiratory movements, first of all. provides essential growth of functionalities of the respiratory muscles expressed in authentic increase of power and speed-power parameters, shortening of time of impellent reaction of respiratory muscles. Improvement of a functional condition of respiratory system, and, in particular, respiratory muscles, caused significant growth of physical working capacity and physical readiness of young sportsmen. PMID:20432701

  12. CABS-flex: server for fast simulation of protein structure fluctuations

    PubMed Central

    Jamroz, Michal; Kolinski, Andrzej; Kmiecik, Sebastian

    2013-01-01

    The CABS-flex server (http://biocomp.chem.uw.edu.pl/CABSflex) implements CABS-model–based protocol for the fast simulations of near-native dynamics of globular proteins. In this application, the CABS model was shown to be a computationally efficient alternative to all-atom molecular dynamics—a classical simulation approach. The simulation method has been validated on a large set of molecular dynamics simulation data. Using a single input (user-provided file in PDB format), the CABS-flex server outputs an ensemble of protein models (in all-atom PDB format) reflecting the flexibility of the input structure, together with the accompanying analysis (residue mean-square-fluctuation profile and others). The ensemble of predicted models can be used in structure-based studies of protein functions and interactions. PMID:23658222

  13. Semi-flexible gas-insulated transmission line using sandwiched discs for intermittent flexing joints

    DOEpatents

    Kommineni, P.R.

    1983-02-15

    A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by the use of main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. The flexing elements are formed by sandwiching together, by fusing, a pair of thin hollow discs which are fixedly secured to both the main conductor sections and the conductor hub section. 4 figs.

  14. Semi-flexible gas-insulated transmission line using sandwiched discs for intermittent flexing joints

    DOEpatents

    Kommineni, Prasad R.

    1983-02-15

    A gas-insulated transmission line includes an outer sheath, an inner conductor, an insulating gas electrically insulating the inner conductor from the outer sheath, and insulating supports insulatably supporting the inner conductor within the outer sheath. The inner conductor is provided with flexibility by the use of main conductor sections which are joined together through a conductor hub section and flexible flexing elements. Stress shields are provided to control the electric field at the locations of the conductor hub sections where the insulating supports are contacting the inner conductor. The flexing elements are formed by sandwiching together, by fusing, a pair of thin hollow discs which are fixedly secured to both the main conductor sections and the conductor hub section.

  15. Experimental Evaluation of a New Tubular Coronary Stent (V-Flexª).

    PubMed

    Shun; Wang; Zhou; Verbeken; Ping; Szilard; Yanming; Jianhua; De Scheerder IK

    1998-11-01

    The safety, efficacy, angiographic and histological effects of a new 316 L, SS seamless stainless steel tubular stent (V-Flexª, Global Therapeutics, Broomfield, Colorado) was evaluated in a porcine coronary and peripheral artery model. Implantation in the right coronary artery was successful in all 16 pigs. Eight pigs were angiographically controlled after 6 weeks and then sacrificed for morphometric analysis. All stented coronary vessels were widely patent at this moment and morphometric analysis showed only a mild fibromuscular neointimal hyperplasia resulting in a neointimal hyperplasia of 1.15 +/- 0.38 mm2. The remaining 8 pigs were controlled and sacrificed at 12 weeks. At that time, all stented vessels were patent and neointimal hyperplasia was 1.22 +/- 0.34 mm2. Comparison with the Palmaz-Schatzª coronary stent (Cordis, Miami, Florida) in a porcine peripheral artery model demonstrated significantly less neointimal hyperplasia at 6 weeks (1.11 +/- 0.73 vs. 2.40 +/- 0.36, p = 0.001) and at 12 weeks (1.53 +/- 0.42 vs. 2.47 +/- 0.63, p = 0.003) for the V-Flex stent. In conclusion, V-Flex coronary stent implantation in a porcine coronary and peripheral arteries results in a high procedural success rate without subacute thrombotic occlusions, despite no further anticoagulation nor antiplatelet therapy. Six and 12 week histopathological and morphometric evaluation demonstrated only a mild fibromuscular neointimal hyperplasia. Comparison with the Palmaz-Schatz coronary stent in a peripheral artery model showed significantly less neointimal hyperplasia in the V-Flex stent. PMID:10762839

  16. Temperature Rise in Human Muscle During Ultrasound Treatments Using Flex-All as a Coupling Agent

    PubMed Central

    Ashton, Douglas F.; Draper, David O.; Myrer, J. William

    1998-01-01

    Objective: To determine if Flex-all 454, as advertised, is effective as a thermal ultrasound couplant. Design and Setting: Research design was a one-factor analysis of variance. Subjects received three (alternating order) ultrasound treatments (1 MHz at 1.5 W/cm2 for 10 minutes) using the following couplants: 50% Flex-all mixed with 50% ultrasound gel; 100% ultrasound gel; and sham ultrasound with 100% Flex-all. Data were collected in a ventilated laboratory. Subjects: Fifteen male and female students (mean age = 24.2 ± 3.7 years). Measurements: Muscle temperature was measured via hypodermic microprobes inserted 3 and 5 cm deep in the medial triceps surae. A visual analogue scale was used to measure perceived heat. Results: At 3 cm, the increases for the gel, 50/50 mixture, and sham were 3.2°C, 2.6°C, and -0.82°C, respectively. At 5 cm, the increases were 2.17°C, 1.80°C, and -0.50°C, respectively. Subjects rated the sham treatment as mild heating (although the temperature dropped) and perceived treatments using the 50/50 mixture to be warmer than treatments using 100% gel couplant. Conclusion: Ultrasound treatments delivered with a 50/50 Flex-all/gel couplant felt warmer to subjects; however, identical treatments with 100% ultrasound gel produced higher muscle temperatures. Clinicians desiring optimal thermal effects should use 100% ultrasound gel as the couplant. ImagesFig 1. PMID:16558500

  17. FlexSAR, a high quality, flexible, cost effective, prototype SAR system

    NASA Astrophysics Data System (ADS)

    Jensen, Mark; Knight, Chad; Haslem, Brent

    2016-05-01

    The FlexSAR radar system was designed to be a high quality, low-cost, flexible research prototype instrument. Radar researchers and practitioners often desire the ability to prototype new or advanced configurations, yet the ability to enhance or upgrade existing radar systems can be cost prohibitive. FlexSAR answers the need for a flexible radar system that can be extended easily, with minimal cost and time expenditures. The design approach focuses on reducing the resources required for developing and validating new advanced radar modalities. Such an approach fosters innovation and provides risk reduction since actual radar data can be collected in the appropriate mode, processed, and analyzed early in the development process. This allows for an accurate, detailed understanding of the corresponding trade space. This paper is a follow-on to last years paper and discusses the advancements that have been made to the FlexSAR system. The overall system architecture is discussed and presented along with several examples illustrating the system utility.

  18. FlexSAR, a high-quality, flexible, cost-effective, prototype SAR system

    NASA Astrophysics Data System (ADS)

    Jensen, Mark; Knight, Chad; Haslem, Brent

    2015-05-01

    The FlexSAR radar system was designed to be a high quality, low-cost, flexible prototype instrument. Many radar researchers and practitioners desire the ability to efficiently prototype novel configurations. However, the cost and time required to modify existing radar systems is a challenging hurdle that can be prohibitive. The FlexSAR system couples an RF design that leverages connectorized components with digital commercial-off-the-shelf (COTS) cards. This design allows for a scalable system that supports software defined radio (SDR) capabilities. This paper focuses on the RF and digital system design, discussing the advantages and disadvantages. The FlexSAR system design objective was to support diverse configurations with minimal non-recurring engineering (NRE) costs. Multiple diverse applications are examined, demonstrating the flexible system nature. The configurations discussed utilize different system parameters (e.g., number of phase-centers, transmit configurations, etc.). The resultant products are examined, illustrating that high-quality data products are still attained.

  19. Flexing is Not Stretching: An Analog Study of Flexure-Induced Fault Growth

    NASA Astrophysics Data System (ADS)

    Supak, S. K.; Bohnenstiehl, D. R.; Buck, W. R.

    2003-12-01

    A thin (5 mm thick) plaster layer floating on a foam rubber substrate is bent and fractured in an analog model of extensional fault growth during lithospheric flexing. The size-frequency scaling of the resulting crack populations were analyzed. Unlike lithospheric stretching models, crack populations formed during these experiments indicate that length- and spacing- frequency distributions are not well described by a power-law model. Rather, these size-frequency data are better described by a negative exponential distribution. The absence of a power-law fault distribution reflects the preferential nucleation and growth of faults in association with stress maxima along the axis of the flexing plate. In contrast, the cracks formed in response to stretching evolve, due to elastic interaction during simultaneous growth, from an initially random distribution of nucleation points to form a self-similar network of fractures. The model predicts a non-power-law fault distribution for any area of moderate or large magnitude lithospheric flexure. The outer rise of trenches is an area of undisputed flexural faulting; however, in these environments, fault distributions have not yet been analyzed. A recent model for axial highs of fast-spreading ridges suggests that lithosphere is flexed significantly as it rafts away from ridge axes. Several studies of ocean floor fault populations near axial highs report non-power-law scaling, consistent with our analog model predictions for plate flexure.

  20. The use of Flex as a viable toolkit for astronomy software applications

    NASA Astrophysics Data System (ADS)

    Gillies, Kim; Conti, Alberto; Rogers, Anthony

    2010-07-01

    The challenges facing the developers of user interfaces for astronomy applications has never been greater. Astronomers and engineers often use well-designed commercial and web applications outside their work environment and have come to expect a similar user experience with applications developed for their work tasks. The connectivity provided by the Internet and the ability to work from anywhere can improve user productivity, but it is a challenge to provide the kind of interactivity and responsiveness needed for astronomical applications to web based projects. It is fair to say that browserbased applications have not been adequate for many kinds of workhorse astronomy applications. The Flex/Actionscript framework from Adobe has been used successfully at the Space Telescope Science Institute in a variety of situations that were not possible with other technologies. In this paper, the Flex framework and technology is briefly introduced followed by a discussion of its advantages and disadvantages and how it addresses user expectations. Three astronomy applications will be presented demonstrating the technology capabilities with useful performance data. Flex/Actionscript is not well known within the astronomy development community, and our goal is to demonstrate that it can be the right choice for many astronomy applications.

  1. Flexible circuits with integrated switches for robotic shape sensing

    NASA Astrophysics Data System (ADS)

    Harnett, C. K.

    2016-05-01

    Digital switches are commonly used for detecting surface contact and limb-position limits in robotics. The typical momentary-contact digital switch is a mechanical device made from metal springs, designed to connect with a rigid printed circuit board (PCB). However, flexible printed circuits are taking over from the rigid PCB in robotics because the circuits can bend while carrying signals and power through moving joints. This project is motivated by a previous work where an array of surface-mount momentary contact switches on a flexible circuit acted as an all-digital shape sensor compatible with the power resources of energy harvesting systems. Without a rigid segment, the smallest commercially-available surface-mount switches would detach from the flexible circuit after several bending cycles, sometimes violently. This report describes a low-cost, conductive fiber based method to integrate electromechanical switches into flexible circuits and other soft, bendable materials. Because the switches are digital (on/off), they differ from commercially-available continuous-valued bend/flex sensors. No amplification or analog-to-digital conversion is needed to read the signal, but the tradeoff is that the digital switches only give a threshold curvature value. Boundary conditions on the edges of the flexible circuit are key to setting the threshold curvature value for switching. This presentation will discuss threshold-setting, size scaling of the design, automation for inserting a digital switch into the flexible circuit fabrication process, and methods for reconstructing a shape from an array of digital switch states.

  2. Efficacy, safety, predictability, aberrations and corneal biomechnical parameters after SMILE and FLEx: Meta-analysis

    PubMed Central

    Ma, Jing; Cao, Nan-Jue; Xia, Li-Kun

    2016-01-01

    AIM To identify possible differences of efficacy, safety, predictability, higher-order aberrations and corneal biomechnical parameters after small-incision lenticule extraction (SMILE) and femtosecond lenticule extraction (FLEx). METHODS A systematic literature retrieval was conducted in Medline, Embase and the Cochrane Library, up to October, 2015. The included studies were subject to a Meta-analysis. Comparison between SMILE and FLEx was measured as pooled odds ratio (OR) or weighted mean differences (WMD). Of 95% confidence intervals (CI) were used to analyze data. RESULTS A total of seven studies were included. Firstly, there were no differences in uncorrected distance visual acuity (UDVA) 20/20 or better (OR, 1.37; 95% CI, 0.69 to 2.69; P=0.37) and logMAR UDVA (WMD, -0.02; 95% CI, -0.05 to 0.01; P=0.17) after SMILE versus FLEx. We found no differences in corrected distance visual acuity (CDVA) unchanged (OR, 0.98; 95% CI, 0.46 to 2.11; P=0.97) and logMAR CDVA (WMD, -0.00; 95% CI, -0.01 to 0.01; P=0.90) either. Secondly, we found no differences in refraction within ±1.00 D (OR, 0.98; 95% CI, 0.13 to 7.28; P=0.99) and ±0.50 D (OR, 1.62; 95% CI, 0.62 to 4.28; P=0.33) of target postoperatively. Thirdly, for higher-order aberrations, we found no differences in the total higher-order aberrations (WMD, -0.04; 95% CI, -0.09 to 0.01; P=0.14), coma (WMD, -0.04; 95% CI, -0.09 to 0.01; P=0.11), spherical (WMD, 0.01; 95% CI, -0.02 to 0.03; P=0.60) and trefoil (WMD, -0.00; 95% CI, -0.04 to 0.03; P=0.76). Furthermore, for corneal biomechanical parameters, we also found no differences (WMD, 0.08; 95% CI, -0.17 to 0.33; P=0.54) after SMILE versus FLEx. CONCLUSION There are no statistically differences in efficacy, safety, predictability, higher-order aberrations and corneal biomechnical parameters postoperative between SMILE and FLEx. PMID:27275436

  3. Charge regulation circuit

    DOEpatents

    Ball, Don G.

    1992-01-01

    A charge regulation circuit provides regulation of an unregulated voltage supply in the range of 0.01%. The charge regulation circuit is utilized in a preferred embodiment in providing regulated voltage for controlling the operation of a laser.

  4. Linear integrated circuits

    NASA Astrophysics Data System (ADS)

    Young, T.

    This book is intended to be used as a textbook in a one-semester course at a variety of levels. Because of self-study features incorporated, it may also be used by practicing electronic engineers as a formal and thorough introduction to the subject. The distinction between linear and digital integrated circuits is discussed, taking into account digital and linear signal characteristics, linear and digital integrated circuit characteristics, the definitions for linear and digital circuits, applications of digital and linear integrated circuits, aspects of fabrication, packaging, and classification and numbering. Operational amplifiers are considered along with linear integrated circuit (LIC) power requirements and power supplies, voltage and current regulators, linear amplifiers, linear integrated circuit oscillators, wave-shaping circuits, active filters, DA and AD converters, demodulators, comparators, instrument amplifiers, current difference amplifiers, analog circuits and devices, and aspects of troubleshooting.

  5. Electrical Circuits and Water Analogies

    ERIC Educational Resources Information Center

    Smith, Frederick A.; Wilson, Jerry D.

    1974-01-01

    Briefly describes water analogies for electrical circuits and presents plans for the construction of apparatus to demonstrate these analogies. Demonstrations include series circuits, parallel circuits, and capacitors. (GS)

  6. Sense circuit arrangement

    NASA Technical Reports Server (NTRS)

    Bohning, Oliver D. (Inventor)

    1976-01-01

    A unique, two-node sense circuit is disclosed. The circuit includes a bridge comprised of resistance elements and a differential amplifier. The two-node circuit is suitably adapted to be arranged in an array comprised of a plurality of discrete bridge-amplifiers which can be selectively energized. The circuit is arranged so as to form a configuration with minimum power utilization and a reduced number of components and interconnections therebetween.

  7. Experimental Tests of UltraFlex Array Designs in Low Earth Orbital and Geosynchronous Charging Environments

    NASA Technical Reports Server (NTRS)

    Galofaro, Joel T.; Vayner, Boris V.; Hillard, Grover B.

    2011-01-01

    The present ground based investigations give the first definitive look describing the expected on-orbit charging behavior of Orion UltraFlex array coupons in the Low Earth Orbital and Geosynchronous Environments. Furthermore, it is important to note that the LEO charging environment also applies to the International Space Station as well as to the lunar mission charging environments. The GEO charging environment includes the bounding case for all lunar orbital and lunar surface mission environments. The UltraFlex thin film photovoltaic array technology has been targeted to become the sole power system for life support and on-orbit power for the manned Aires Crew Exploration Vehicle. It is therefore, crucial to gain an understanding of the complex charging behavior to answer some of the basic performance and survivability issues in an attempt to ascertain that a single UltraFlex array design will be able to cope with the projected worst case LEO and GEO charging environments. Testing was limited to four array coupons, two coupons each from two different array manufactures, Emcore and Spectrolab. The layout of each array design is identical and varies only in the actual cell technology used. The individual array cells from each manufacturer have an antireflection layered coating and come in two different varieties either uncoated (only AR coating) or coated with a thin conducting ITO layer. The LEO Plasma tests revealed that all four coupons passed the arc threshold -120 V bias tests. GEO electron gun charging tests revealed that only front side area of ITO coated coupons passed tests. Only the Emcore AR array passed backside Stage 2 GEO Tests.

  8. Improved lenticule shape for hyperopic femtosecond lenticule extraction (ReLEx(®) FLEx): a pilot study.

    PubMed

    Sekundo, Walter; Reinstein, Dan Z; Blum, Marcus

    2016-05-01

    The aim of this study is to establish and to prove a new lenticule shape for the treatment of hyperopia using a 500 kHz femtosecond laser and the femtosecond lenticule extraction (ReLEx(®) FLEx) technique. Improved lenticule shapes with a large transition zone of at least 2 mm adjusted to the 5.75 mm optical zone were designed. A prospective pilot study on nine eyes of five patients who underwent an uncomplicated FLEx using VisuMax(®) femtosecond laser (Carl Zeiss Meditec AG) for spherical hyperopia was performed. Patients' mean age was 55.5 years, and the preoperative manifest spherical equivalent (SE) was +1.82 D (range +1.25 to +3.00 D). Because of the presbyopic age and in order to compensate for a possible regression, the treatment was aimed at low myopia (mean target SE was -0.88 D with a mean treatment refraction of +2.69 D). At the last follow-up, after 9 months, 33 % were within ±0.50 D and 78 % within ±1.00 D of intended correction. Thirty-three percent lost one line, and 11 % gained one line corrected distance visual acuity (CDVA). On average, the centre of the optical zone was 0.34 ± 0.17 mm from the corneal vertex. No adverse effects were observed. This pilot study confirms that the improved lenticule's design with a large optical and transition zone can achieve good centration and acceptable results for spherical hyperopia using FLEx. The next steps are to extend the study to spherocylindrical hyperopic treatments and to increase the number of eyes for better assessment of refractive outcome. PMID:26868029

  9. Electrical Circuit Simulation Code

    Energy Science and Technology Software Center (ESTSC)

    2001-08-09

    Massively-Parallel Electrical Circuit Simulation Code. CHILESPICE is a massively-arallel distributed-memory electrical circuit simulation tool that contains many enhanced radiation, time-based, and thermal features and models. Large scale electronic circuit simulation. Shared memory, parallel processing, enhance convergence. Sandia specific device models.

  10. Piezoelectric drive circuit

    DOEpatents

    Treu, C.A. Jr.

    1999-08-31

    A piezoelectric motor drive circuit is provided which utilizes the piezoelectric elements as oscillators and a Meacham half-bridge approach to develop feedback from the motor ground circuit to produce a signal to drive amplifiers to power the motor. The circuit automatically compensates for shifts in harmonic frequency of the piezoelectric elements due to pressure and temperature changes. 7 figs.

  11. Piezoelectric drive circuit

    DOEpatents

    Treu, Jr., Charles A.

    1999-08-31

    A piezoelectric motor drive circuit is provided which utilizes the piezoelectric elements as oscillators and a Meacham half-bridge approach to develop feedback from the motor ground circuit to produce a signal to drive amplifiers to power the motor. The circuit automatically compensates for shifts in harmonic frequency of the piezoelectric elements due to pressure and temperature changes.

  12. Thermal tests of MC3811 rigid/flex printed wiring boards

    SciTech Connect

    Gentry, F.L.

    1990-10-01

    Rigid/flex multilayer printed wiring boards are more sensitive to thermal environmental changes than conventional printed wiring boards. This is manifested because of a composition of dissimilar materials used within the construction of this type of product. During fabrication and assembly, stresses can develop within the plated-through holes from differences in thermal properties of the rigid and flexible materials, primarily thermal coefficient of expansion. Thermal shock and thermal stress tests and rework simulation as defined in MIL-P-50884 have been performed in this study as indicators of processing quality to detect faults and to verify improvements in board reliability. 3 refs., 17 figs., 3 tabs.

  13. Topographic Analysis of HyFlex® Controlled Memory Nickel–Titanium Files

    PubMed Central

    Al-Sudani, Dina

    2014-01-01

    Background: The multiple uses of HyFlex® controlled memory (CM) rotary instruments (Coltene-Whaledent, Allstetten, Switzerland) have been recommended after sterilization. The purpose of this study was to analyze the surface defects on HyFlex® instruments after use and to determine their ability to return to their original shape after autoclaving. Materials and Methods: Twenty-four new HyFlex® files were scanned using micro-computed tomography before the initial use, after use until defects were visible and after autoclaving. Surface analysis was performed on each file to determine the changes in the files after deformation; defects were recorded as unwinding and curving. These changes were categorized according to the severity, and the initial and final scans of the files were superimposed to illustrate the recovery of the files to their original shape. The data were analyzed using Chi-square and t-test. Results: The t-test of Student’s Newman–Keuls revealed a significant difference (P < 0.05) between unused and used files, almost all files exhibited visible defects without fractures, including unwinding and curving associated with unwinding. The most frequently observed defect was unwinding of the spirals (100%), whereas curving associated with unwinding was infrequently observed. A Chi-square test showed that the deformation (curve: P = 0.000, and unwinding: P = 0.011, incidence depended on the size of the files. The greatest frequency of curving occurred in the small files #20/0.04 and #20/0.06, the difference was statistically significant from all file sizes (P < 0.05). The majority of the files (79%) were able to restore the unwinding and regain their original shape after autoclaving. The highest rate of unrestored files was observed on #20/0.04 and #20/0.06 instruments, and the difference was statistically significant from all file sizes (P < 0.05). Conclusion: HyFlex® CM nickel-titanium files appear to regain their original shape after sterilization

  14. Performance of FORTRAN floating-point operations on the Flex/32 multicomputer

    NASA Technical Reports Server (NTRS)

    Crockett, Thomas W.

    1987-01-01

    A series of experiments has been run to examine the floating-point performance of FORTRAN programs on the Flex/32 (Trademark) computer. The experiments are described, and the timing results are presented. The time required to execute a floating-point operation is found to vary considerbaly depending on a number of factors. One factor of particular interest from an algorithm design standpoint is the difference in speed between common memory accesses and local memory accesses. Common memory accesses were found to be slower, and guidelines are given for determinig when it may be cost effective to copy data from common to local memory.

  15. The Flex Track: Flexible Partitioning between Low- and High-Acuity Areas of an Emergency Department

    PubMed Central

    Laker, Lauren F.; Froehle, Craig M.; Lindsell, Christopher J.; Ward, Michael J.

    2014-01-01

    Study Objective EDs with both low- and high-acuity treatment areas often have fixed allocation of resources, regardless of demand. We demonstrate the utility of discrete-event simulation to evaluate flexible partitioning between low- and high-acuity ED areas to identify the best operational strategy for subsequent implementation. Methods A discrete-event simulation was used to model patient flow through a 50-bed, urban, teaching ED that handles 85,000 patient visits annually. The ED has historically allocated ten beds to a Fast Track for low-acuity patients. We estimated the effect of a Flex Track policy, which involved switching up to five of these Fast Track beds to serving both low- and high-acuity patients, on patient waiting times. When the high-acuity beds were not at capacity, low-acuity patients were given priority access to flexible beds. Otherwise, high-acuity patients were given priority access to flexible beds. Wait times were estimated for patients by disposition and emergency severity index (ESI) score. Results A Flex Track policy using three flexible beds produced the lowest mean patient waiting of 30.9 (95% CI 30.6–31.2) minutes. The typical Fast Track approach of rigidly separating high- and low–acuity beds produced a mean patient wait time of 40.6 (95% CI 40.2–50.0) minutes, 31% higher than the three-bed Flex Track. A completely flexible ED, where all beds can accommodate any patient, produced mean wait times of 35.1 (95% CI 34.8–35.4) minutes. The results from the three-bed Flex Track scenario were robust, performing well across a range of scenarios involving higher and lower patient volumes and care durations. Conclusion Using discrete-event simulation, we have shown that adding some flexibility into bed allocation between low- and high-acuity can provide substantial reductions in overall patient waiting and a more efficient ED. PMID:24954578

  16. Evaluation of Ares-I Control System Robustness to Uncertain Aerodynamics and Flex Dynamics

    NASA Technical Reports Server (NTRS)

    Jang, Jiann-Woei; VanTassel, Chris; Bedrossian, Nazareth; Hall, Charles; Spanos, Pol

    2008-01-01

    This paper discusses the application of robust control theory to evaluate robustness of the Ares-I control systems. Three techniques for estimating upper and lower bounds of uncertain parameters which yield stable closed-loop response are used here: (1) Monte Carlo analysis, (2) mu analysis, and (3) characteristic frequency response analysis. All three methods are used to evaluate stability envelopes of the Ares-I control systems with uncertain aerodynamics and flex dynamics. The results show that characteristic frequency response analysis is the most effective of these methods for assessing robustness.

  17. P80 SRM low torque flex-seal development - thermal and chemical modeling of molding process

    NASA Astrophysics Data System (ADS)

    Descamps, C.; Gautronneau, E.; Rousseau, G.; Daurat, M.

    2009-09-01

    The development of the flex-seal component of the P80 nozzle gave the opportunity to set up new design and manufacturing process methods. Due to the short development lead time required by VEGA program, the usual manufacturing iterative tests work flow, which is usually time consuming, had to be enhanced in order to use a more predictive approach. A newly refined rubber vulcanization description was built up and identified on laboratory samples. This chemical model was implemented in a thermal analysis code. The complete model successfully supports the manufacturing processes. These activities were conducted with the support of ESA/CNES Research & Technologies and DGA (General Delegation for Armament).

  18. Tech Flex

    ERIC Educational Resources Information Center

    Demski, Jennifer

    2012-01-01

    On many college campuses, the 21st century classroom is the exception rather than the norm. Here's what usually happens: A forward-thinking administrator pushes for a pilot program to redesign a handful of classrooms. The resulting learning spaces are cutting edge and successful--in high demand among faculty and students alike. And that's as far…

  19. CIRCUITS FOR CURRENT MEASUREMENTS

    DOEpatents

    Cox, R.J.

    1958-11-01

    Circuits are presented for measurement of a logarithmic scale of current flowing in a high impedance. In one form of the invention the disclosed circuit is in combination with an ionization chamber to measure lonization current. The particular circuit arrangement lncludes a vacuum tube having at least one grid, an ionization chamber connected in series with a high voltage source and the grid of the vacuum tube, and a d-c amplifier feedback circuit. As the ionization chamber current passes between the grid and cathode of the tube, the feedback circuit acts to stabilize the anode current, and the feedback voltage is a measure of the logaritbm of the ionization current.

  20. In Vitro Analysis of Pyrogenicity and Cytotoxicity Profiles of Flex Sensors to be Used to Sense Human Joint Postures

    PubMed Central

    Saggio, Giovanni; Bianchi, Luigi; Castelli, Silvia; Santucci, Marilina B.; Fraziano, Maurizio; Desideri, Alessandro

    2014-01-01

    Flex sensors can be usefully adopted as mechanical-electrical transducers to measure human joint movements, since their electrical resistance varies proportionally to the angle assumed by the joint under measure. Over time, these sensors have been investigated in terms of mechanical and electrical behavior, but no reports have detailed the possibility of their adoption not just on top but under the human skin of the joint. To this aim, our work investigated in vitro the pyrogenic potential and cytotoxicity of some commercially available flex sensors as a first step toward the necessary requirements regarding their biocompatibility, to predict possible foreign body reactions when used in vivo. Results demonstrated that some specific flex sensors satisfy such requirements. PMID:24988382

  1. A flex-compressive-mode piezoelectric transducer for mechanical vibration/strain energy harvesting.

    PubMed

    Li, Xiaotian; Guo, Mingsen; Dong, Shuxiang

    2011-04-01

    A piezoelectric transducer for harvesting energy from ambient mechanical vibrations/strains under pressure condition was developed. The proposed transducer was made of two ring-type piezoelectric stacks, one pair of bow-shaped elastic plates, and one shaft that pre-compresses them. This transducer works in flex-compressive (F-C) mode, which is different from a conventional flex-tensional (F-T) one, to transfer a transversely applied force F into an amplified longitudinal force N pressing against the two piezo-stacks via the two bowshaped elastic plates, generating a large electric voltage output via piezoelectric effect. Our experimental results show that without an electric load, an F-C mode piezo-transducer could generate a maximum electric voltage output of up to 110 Vpp, and with an electric load of 40 κΩ, it a maximum power output of 14.6 mW under an acceleration excitation of 1 g peak-peak at the resonance frequency of 87 Hz. PMID:21507747

  2. Tracking C. elegans and its neuromuscular activity using NemaFlex

    NASA Astrophysics Data System (ADS)

    van Bussel, Frank; Rahman, Mizanur; Hewitt, Jennifer; Blawzdziewicz, Jerzy; Driscoll, Monica; Szewczyk, Nathaniel; Vanapalli, Siva

    Recently, a novel platform has been developed for studying the behavior and physical characteristics of the nematode C. elegans. This is NemaFlex, developed by the Vanapalli group at Texas Tech University to analyze movement and muscular strength of crawling C. elegans. NemaFlex is a microfluidic device consisting of an array of deformable PDMS pillars, with which the C. elegans interacts in the course of moving through the system. Deflection measurements then allow us to calculate the force exerted by the worm via Euler-Bernoulli beam theory. For the procedure to be fully automated a fairly sophisticated software analysis has to be developed in tandem with the physical device. In particular, the usefulness of the force calculations is highly dependent on the accuracy and volume of the deflection measurements, which would be prohibitively time-consuming if carried out by hand/eye. In order to correlate the force results with muscle activations the C. elegans itself has to be tracked simultaneously, and pillar deflections precisely associated with mechanical-contact on the worm's body. Here we will outline the data processing and analysis routines that have been implemented in order to automate the calculation of these forces and muscular activations.

  3. The FlexX database docking environment--rational extraction of receptor based pharmacophores.

    PubMed

    Claussen, Holger; Gastreich, Marcus; Apelt, Volker; Greene, Jonathan; Hindle, Sally A; Lemmen, Christian

    2004-01-01

    We present an integrated docking environment that allows for iterative and interactive detailed analysis of many docking solutions. All docking information is stored in an ORACLE database. New scoring schemes (e.g. target-specific scoring functions) as well as various types of filters can be easily defined and tested within this environment. As an example application we investigated the validity of the following hypothesis: If a docking procedure can lead to enrichments significantly better than random then a bias towards (partially) correct placements should be detectable. Such bias in terms of a preference for certain interacting groups within the active site can be used to select a set of receptor-based pharmacophore constraints, which in turn might be used to enhance the docking procedure. As a proof of concept for this approach we performed docking studies on three targets: thrombin, the cyclin-dependent kinase 2 (CDK2) and the angiotensin converting enzyme (ACE). We docked a set of known active compounds with standard FlexX and derived three sets of target-specific receptor-based pharmacophore constraints by statistical analysis of the predicted placements. Applying these receptor-based constraints in a virtual screening protocol utilizing FlexX-Pharm led to significantly improved enrichments. PMID:16472219

  4. Refinement of atomic models in high resolution EM reconstructions using Flex-EM and local assessment

    PubMed Central

    Joseph, Agnel Praveen; Malhotra, Sony; Burnley, Tom; Wood, Chris; Clare, Daniel K.; Winn, Martyn; Topf, Maya

    2016-01-01

    As the resolutions of Three Dimensional Electron Microscopic reconstructions of biological macromolecules are being improved, there is a need for better fitting and refinement methods at high resolutions and robust approaches for model assessment. Flex-EM/MODELLER has been used for flexible fitting of atomic models in intermediate-to-low resolution density maps of different biological systems. Here, we demonstrate the suitability of the method to successfully refine structures at higher resolutions (2.5–4.5 Å) using both simulated and experimental data, including a newly processed map of Apo-GroEL. A hierarchical refinement protocol was adopted where the rigid body definitions are relaxed and atom displacement steps are reduced progressively at successive stages of refinement. For the assessment of local fit, we used the SMOC (segment-based Manders’ overlap coefficient) score, while the model quality was checked using the Qmean score. Comparison of SMOC profiles at different stages of refinement helped in detecting regions that are poorly fitted. We also show how initial model errors can have significant impact on the goodness-of-fit. Finally, we discuss the implementation of Flex-EM in the CCP-EM software suite. PMID:26988127

  5. Refinement of atomic models in high resolution EM reconstructions using Flex-EM and local assessment.

    PubMed

    Joseph, Agnel Praveen; Malhotra, Sony; Burnley, Tom; Wood, Chris; Clare, Daniel K; Winn, Martyn; Topf, Maya

    2016-05-01

    As the resolutions of Three Dimensional Electron Microscopic reconstructions of biological macromolecules are being improved, there is a need for better fitting and refinement methods at high resolutions and robust approaches for model assessment. Flex-EM/MODELLER has been used for flexible fitting of atomic models in intermediate-to-low resolution density maps of different biological systems. Here, we demonstrate the suitability of the method to successfully refine structures at higher resolutions (2.5-4.5Å) using both simulated and experimental data, including a newly processed map of Apo-GroEL. A hierarchical refinement protocol was adopted where the rigid body definitions are relaxed and atom displacement steps are reduced progressively at successive stages of refinement. For the assessment of local fit, we used the SMOC (segment-based Manders' overlap coefficient) score, while the model quality was checked using the Qmean score. Comparison of SMOC profiles at different stages of refinement helped in detecting regions that are poorly fitted. We also show how initial model errors can have significant impact on the goodness-of-fit. Finally, we discuss the implementation of Flex-EM in the CCP-EM software suite. PMID:26988127

  6. Effects of an adapted physical activity program in a group of elderly subjects with flexed posture: clinical and instrumental assessment

    PubMed Central

    Benedetti, Maria Grazia; Berti, Lisa; Presti, Chiara; Frizziero, Antonio; Giannini, Sandro

    2008-01-01

    Background Flexed posture commonly increases with age and is related to musculoskeletal impairment and reduced physical performance. The purpose of this clinical study was to systematically compare the effects of a physical activity program that specifically address the flexed posture that marks a certain percentage of elderly individuals with a non specific exercise program for 3 months. Methods Participants were randomly divided into two groups: one followed an Adapted Physical Activity program for flexed posture and the other one completed a non-specific physical activity protocol for the elderly. A multidimensional clinical assessment was performed at baseline and at 3 months including anthropometric data, clinical profile, measures of musculoskeletal impairment and disability. The instrumental assessment of posture was realized using a stereophotogrammetric system and a specific biomechanical model designed to describe the reciprocal position of the body segments on the sagittal plane in a upright posture. Results The Adapted Physical Activity program determined a significant improvement in several key parameters of the multidimensional assessment in comparison to the non-specific protocol: decreased occiput-to-wall distance, greater lower limb range of motion, better flexibility of pectoralis, hamstrings and hip flexor muscles, increased spine extensor muscles strength. Stereophotogrammetric analysis confirmed a reduced protrusion of the head and revealed a reduction in compensative postural adaptations to flexed posture characterized by knee flexion and ankle dorsiflexion in the participants of the specific program. Conclusion The Adapted Physical Activity program for flexed posture significantly improved postural alignment and musculoskeletal impairment of the elderly. The stereophotogrammetric evaluation of posture was useful to measure the global postural alignment and especially to analyse the possible compensatory strategies at lower limbs in flexed

  7. A comparison of conventional tube and EndoFlex tube for tracheal intubation in patients with a cervical spine immobilisation

    PubMed Central

    2013-01-01

    Background The EndoFlex is a new type of tracheal tube with an adjustable distal tip that can be bent without the use of a stylet. The aim of this study was to compare a standard endotracheal tube with the EndoFlex tracheal tube for intubation in patients with simulated cervical spine injury. Methods A group of 60 patients without any kind of the cervical spine injury, classified as the ASA physiological scale I or II and qualified for elective surgery procedures were intubated with the use of classical Macintosh laryngoscope, and either a standard endotracheal tube with the intubation stylet in it or EndoFlex tube without stylet. The subjects were randomized into two subgroups. All patients have had the cervical collar placed on their neck for the simulation of intubation procedure in case of the spinal injury. Results The intubation procedure was performed by 16 anesthetists with different experience (5-19 yrs). Time of intubation with the use of EndoFlex tube was similar to that with a the use of standard endotracheal tube and intubation stylet: Me (median) 19.5 s [IQR (interquatile range) 18-50] vs. Me 20 s [IQR 17-60] respectively (p = 0.9705). No significant additional maneuvers were necessary during intubation with the use of EndoFlex tube in comparison with standard endotracheal tube (70% vs. 56.6%) (p = 0.4220). Subjective assessment of the usability of both tubes revealed that more anesthesiologists found intubations with the use of EndoFlex more demanding than intubation with conventional tracheal tube and intubation stylet. The assessment of usability: very easy 3.3% vs. 20%, easy 83.4% vs. 56.7%, difficult 10% vs. 20% and very difficult 3.3% vs. 3.3% for standard endotracheal tube with stylet and EndoFlex, respectively. Conclusion In conclusion we asses, that the EndoFlex tube does not improve intubation success rate, in fact it requires more maneuvers facilitating intubation and was found to be more difficult to use. PMID:24267640

  8. Traumatic Dislodgement of Tibial Polyethylene Insert after a High-Flex Posterior-Stabilized Total Knee Replacement

    PubMed Central

    Astoul Bonorino, Juan Felix; Slullitel, Pablo Ariel Isidoro; Kido, Gonzalo Rodrigo; Bongiovanni, Santiago; Vestri, Renato; Carbó, Lisandro

    2015-01-01

    Many pathologic entities can produce a painful total knee replacement (TKR) that may lead to potential prosthetic failure. Polyethylene insert dissociation from the tibial baseplate has been described most frequently after mobile-bearing and cruciate-retaining TKRs. However, only 3 tibial insert dislocations in primary fixed-bearing High-Flex posterior-stabilized TKRs have been reported. We present a new case of tibial insert dislocation in a High-Flex model that shares similarities and differences with the cases reported, facilitating the analysis of the potential causes, which still remain undefined. PMID:26457215

  9. Source circuit design considerations

    NASA Astrophysics Data System (ADS)

    Noel, G. T.

    1983-11-01

    The cost of several circuit configurations for large (5MW) array fields were investigated to assess the relative costs of high and low voltage configurations. Three source circuit NOC voltages were evaluated: 400V (ungrounded), 800V (+ or 400V center grounded), and 2000V (+ or - 1000V center grounded). Four source circuit configurations were considered for each of the three NOC voltages. The configurations correspond to source circuit currents of 15, 30, 45, and 60 amperes, respectively. Conceptual layouts for 5MW building blocks for each of the above configurations were developed. The designs were optimized to minimize BOS electrical and structural costs. Only the BOS electrical costs were evaluated. The designs were broken down into the following elements for cost: (1) basic source circuit intermodule wiring, bypass diodes and associated hardware, source circuit to J-Box wiring, etc; (2) J-Box blocking diodes, varistors, heat sinks, and housing; (3) disconnects source circuit disconnects, fuses, and housing; (4) bus cabling J-Box to PCU interface wiring, and trenching; (5) interface bus bar, group disconnects, and fuses; and (6) fault detection shunts, signal wire, electronics, and alarm. It is concluded that high voltage low current circuits are not economical, at higher currents high and low voltage circuit costs approach each other, high voltage circuits are not likely to offer near term advantage, and development work/manufacturer stimulation is needed to develop low cost high voltage hardware.

  10. Source circuit design considerations

    NASA Technical Reports Server (NTRS)

    Noel, G. T.

    1983-01-01

    The cost of several circuit configurations for large (5MW) array fields were investigated to assess the relative costs of high and low voltage configurations. Three source circuit NOC voltages were evaluated: 400V (ungrounded), 800V (+ or 400V center grounded), and 2000V (+ or - 1000V center grounded). Four source circuit configurations were considered for each of the three NOC voltages. The configurations correspond to source circuit currents of 15, 30, 45, and 60 amperes, respectively. Conceptual layouts for 5MW building blocks for each of the above configurations were developed. The designs were optimized to minimize BOS electrical and structural costs. Only the BOS electrical costs were evaluated. The designs were broken down into the following elements for cost: (1) basic source circuit intermodule wiring, bypass diodes and associated hardware, source circuit to J-Box wiring, etc; (2) J-Box blocking diodes, varistors, heat sinks, and housing; (3) disconnects source circuit disconnects, fuses, and housing; (4) bus cabling J-Box to PCU interface wiring, and trenching; (5) interface bus bar, group disconnects, and fuses; and (6) fault detection shunts, signal wire, electronics, and alarm. It is concluded that high voltage low current circuits are not economical, at higher currents high and low voltage circuit costs approach each other, high voltage circuits are not likely to offer near term advantage, and development work/manufacturer stimulation is needed to develop low cost high voltage hardware.

  11. Introduction of argon beam coagulation functionality to robotic procedures using the ABC D-Flex probe: equivalency to an existing laparoscopic instrument

    NASA Astrophysics Data System (ADS)

    Merchel, Renée. A.; Barnes, Kelli S.; Taylor, Kenneth D.

    2015-03-01

    INTRODUCTION: The ABC® D-Flex Probe utilizes argon beam coagulation (ABC) technology to achieve hemostasis during minimally invasive surgery. A handle on the probe allows for integration with robotic surgical systems and introduces ABC to the robotic toolbox. To better understand the utility of D-Flex, this study compares the performance of the D-Flex probe to an existing ABC laparoscopic probe through ex vivo tissue analysis. METHODS: Comparisons were performed to determine the effect of four parameters: ABC device, tissue type, activation duration, and distance from tissue. Ten ABC D-Flex probes were used to create 30 burn samples for each comparison. Ex vivo bovine liver and porcine muscle were used as tissue models. The area and depth of each burn was measured using a light microscope. The resulting dimensional data was used to correlate tissue effect with each variable. RESULTS: D-Flex created burns which were smaller in surface area than the laparoscopic probe at all power levels. Additionally, D-Flex achieved thermal penetration levels equivalent to the laparoscopic probe. CONCLUSION: D-Flex implements a small 7F geometry which creates a more focused beam. When used with robotic precision, quick localized superficial hemostasis can be achieved with minimal collateral damage. Additionally, D-Flex achieved equivalent thermal penetration levels at lower power and argon flow-rate settings than the laparoscopic probe.

  12. [Shunt and short circuit].

    PubMed

    Rangel-Abundis, Alberto

    2006-01-01

    Shunt and short circuit are antonyms. In French, the term shunt has been adopted to denote the alternative pathway of blood flow. However, in French, as well as in Spanish, the word short circuit (court-circuit and cortocircuito) is synonymous with shunt, giving rise to a linguistic and scientific inconsistency. Scientific because shunt and short circuit made reference to a phenomenon that occurs in the field of the physics. Because shunt and short circuit are antonyms, it is necessary to clarify that shunt is an alternative pathway of flow from a net of high resistance to a net of low resistance, maintaining the stream. Short circuit is the interruption of the flow, because a high resistance impeaches the flood. This concept is applied to electrical and cardiovascular physiology, as well as to the metabolic pathways. PMID:17257492

  13. Automatic circuit interrupter

    NASA Technical Reports Server (NTRS)

    Dwinell, W. S.

    1979-01-01

    In technique, voice circuits connecting crew's cabin to launch station through umbilical connector disconnect automatically unused, or deadened portion of circuits immediately after vehicle is launched, eliminating possibility that unused wiring interferes with voice communications inside vehicle or need for manual cutoff switch and its associated wiring. Technique is applied to other types of electrical actuation circuits, also launch of mapped vehicles, such as balloons, submarines, test sleds, and test chambers-all requiring assistance of ground crew.

  14. Regenerative feedback resonant circuit

    DOEpatents

    Jones, A. Mark; Kelly, James F.; McCloy, John S.; McMakin, Douglas L.

    2014-09-02

    A regenerative feedback resonant circuit for measuring a transient response in a loop is disclosed. The circuit includes an amplifier for generating a signal in the loop. The circuit further includes a resonator having a resonant cavity and a material located within the cavity. The signal sent into the resonator produces a resonant frequency. A variation of the resonant frequency due to perturbations in electromagnetic properties of the material is measured.

  15. Remote reset circuit

    DOEpatents

    Gritzo, R.E.

    1985-09-12

    A remote reset circuit acts as a stand-along monitor and controller by clocking in each character sent by a terminal to a computer and comparing it to a given reference character. When a match occurs, the remote reset circuit activates the system's hardware reset line. The remote reset circuit is hardware based centered around monostable multivibrators and is unaffected by system crashes, partial serial transmissions, or power supply transients. 4 figs.

  16. Remote reset circuit

    DOEpatents

    Gritzo, Russell E.

    1987-01-01

    A remote reset circuit acts as a stand-alone monitor and controller by clocking in each character sent by a terminal to a computer and comparing it to a given reference character. When a match occurs, the remote reset circuit activates the system's hardware reset line. The remote reset circuit is hardware based centered around monostable multivibrators and is unaffected by system crashes, partial serial transmissions, or power supply transients.

  17. Printed circuit board industry.

    PubMed

    LaDou, Joseph

    2006-05-01

    The printed circuit board is the platform upon which microelectronic components such as semiconductor chips and capacitors are mounted. It provides the electrical interconnections between components and is found in virtually all electronics products. Once considered low technology, the printed circuit board is evolving into a high-technology product. Printed circuit board manufacturing is highly complicated, requiring large equipment investments and over 50 process steps. Many of the high-speed, miniaturized printed circuit boards are now manufactured in cleanrooms with the same health and safety problems posed by other microelectronics manufacturing. Asia produces three-fourths of the world's printed circuit boards. In Asian countries, glycol ethers are the major solvents used in the printed circuit board industry. Large quantities of hazardous chemicals such as formaldehyde, dimethylformamide, and lead are used by the printed circuit board industry. For decades, chemically intensive and often sloppy manufacturing processes exposed tens of thousands of workers to a large number of chemicals that are now known to be reproductive toxicants and carcinogens. The printed circuit board industry has exposed workers to high doses of toxic metals, solvents, acids, and photolithographic chemicals. Only recently has there been any serious effort to diminish the quantity of lead distributed worldwide by the printed circuit board industry. Billions of electronics products have been discarded in every region of the world. This paper summarizes recent regulatory and enforcement efforts. PMID:16580876

  18. Open-source modular solutions for isostasy and flexure of the lithosphere: gFlex v1.0

    NASA Astrophysics Data System (ADS)

    Wickert, Andrew

    2015-04-01

    In convergent margin settings, flexural subsidence of sedimentary basins is initiated by tectonically-induced stresses, and continues with a combination of (1) sediment loading, (2) concurrent erosional unloading of the surrounding mountain ranges, and (3) water loading and/or unloading. These stresses and the implicit positive feedback -- that sediment loading helps to maintain a topographic low into which more sediments are deposited -- has long been recognized and deserves explicit treatment in numerical models. Here I present the newly-released version 1.0 of the open-source model gFlex, simulates isostasy and flexure of the lithosphere. gFlex can compute flexural isostasy along one-dimensional transects and across two-dimensional surfaces with either constant or variable lithospheric effective elastic thickness. Variable elastic thickness is an especially important component to modeling convergent margins, where active tectonics can produce an underlying lithosphere with nonuniform rheology. gFlex can be run as a standalone model, as part of the GRASS GIS environment (for straightforward integration with data and to take advantage of the GRASS GIS graphical user interface), or as a coupled component of a larger model simulation as part of the Community Surface Dynamics Modeling System (CSDMS). The source code is freely available from the University of Minnesota Earth-surface science GitHub repository at https://github.com/umn-earth-surface/gFlex, and potential users are encouraged to download and run the model and to suggest possible future improvements.

  19. Feasibility Study of NI's FlexRIO Platform for High-Throughput Data Acquisition

    NASA Astrophysics Data System (ADS)

    Sprow, Aaron; Crawford, Christopher; Lovell, Simon; Nab Collaboration

    2013-10-01

    The Nab neutron decay correlation experiment requires high energy and time resolution, and a multipixel low threshold trigger to efficiently detect 30 keV protons. Digital waveforms must be read out for offline pulse-shape analysis from all neighboring channels of hits in the two 128-pixel ion implanted silicon detectors. National Instrument's FlexRIO system has a unique data acquisition architecture based on a single 500 ms ring buffer which continuously records data. Custom discriminators can be programmed by the user on the FPGA with LabVIEW graphical programming language, and multichannel trigger logic can be implemented on the CPU using the bidirectional, high bandwidth, low latency PCI bus. We developed a low-threshold trigger using a trapezoid energy filter to test the feasibility of this system. We will present our experience programming the trigger and the resulting performance, including detection efficiency and background noise rejection.

  20. Replacement for a Flex Hose Coating at the Space Shuttle Launch Pad

    NASA Technical Reports Server (NTRS)

    Whitten, Mary; Vinje, Rubiela; Curran, Jerome; Meneghelli, Barry; Calle, Luz Marina

    2009-01-01

    Aerocoat AR-7 is a coating that has been used to protect stainless steel flex hoses at NASA's Kennedy Space Center launch complex and hydraulic lines of the mobile launch platform (MLP). This coating has great corrosion control performance and low temperature application. AR-7 was developed by NASA and produced exclusively for NASA but its production has been discontinued due to its high content of volatile organic compounds (VOC) and significant environmental impact. The purpose of this project was to select and evaluate candidate coatings to find a replacement coating that is more environmentally friendly, with similar properties to AR-7. No coatings were identified that perform the same as AR-7 in all areas. Candidate coatings failed in comparison to AR-7 in salt fog, beachside atmospheric exposure, pencil hardness, Mandrel bend, chemical compatibility, adhesion, and ease of application tests. However, two coatings were selected for further evaluation.

  1. The first North American use of the Pipeline Flex flow diverter.

    PubMed

    Duckworth, Edward A M; Nickele, Christopher; Hoit, Daniel; Belayev, Andrey; Moran, Christopher J; Arthur, Adam S

    2015-01-01

    Flow diversion for the management of intracranial aneurysms represents a paradigm shift in how aneurysms are managed. The Pipeline embolization device (PED) is, to date, the only flow diverter approved for use in the USA by the Food and Drug Administration. Limitations and complications with new treatment strategies are inevitable, and with the PED there have been reports of complications, most commonly with challenging deployments. Once deployment has been initiated, the device is 'one-way'; it can only be deployed further or removed. Yet, situations arise in which the ability to recapture or reposition the device would be advantageous. A second-generation Pipeline has been developed that addresses these concerns. We report the first use in North America of this second-generation Pipeline device: the Pipeline Flex. We discuss our rationale for using the device, our impressions of its operation, and the relevant literature concerning the current state of flow diversion. PMID:25636625

  2. Evaluation of candidate alloys for the construction of metal flex hoses in the STS launch environment

    NASA Technical Reports Server (NTRS)

    Macdowell, Louis G., III; Ontiveros, Cordelia

    1988-01-01

    Various vacuum jacketed cryogenic supply lines at the Shuttle launch site use convoluted flexible expansion joints. The atmosphere at the launch site has a very high salt content, and during a launch fuel combustion products include hydrochloric acid. This extremely corrosive environment has caused pitting corrosion failure in the flex hoses, which were made out of 304L stainless steel. A search was done to find a more corrosion resistant replacement material. Nineteen metal alloys were tested. Tests which were performed include electrochemical corrosion testing, accelerated corrosion testing in a salt fog chamber, long term exposure at the beach corrosion testing site, and pitting corrosion tests in ferric chloride solution. Based on the results, the most corrosion resistant alloys were found to be, in order, Hastelloy C-22, Inconel 625, Hastelloy C-276, Hastelloy C-4, and Inco Alloy G-3. Of these top five alloys, the Hastelloy C-22 stands out as being the best of the alloys tested.

  3. Design, analysis and testing of a piezoelectric flex transducer for harvesting bio-kinetic energy

    NASA Astrophysics Data System (ADS)

    Daniels, A.; Zhu, M.; Tiwari, A.

    2013-12-01

    The increasing prevalence of low power consuming electronics brings greater potential to mobile energy harvesting devices as a possible power source. A new piezoelectric energy harvesting device, called the piezoelectric flex transducer (PFT), is presented and developed. A Finite Element Model (FEM) was developed to design and analyse the PFT. The PFT consists of a piezoelectric element sandwiched between substrate layers and metal endcaps that are able to amplify the axial force on the piezoelectric element. Based on the concept of the Cymbal transducer, the PFT can withstand higher forces, was retrofitted into a shoe and used to power a wireless sensor module whilst the subject with a body weight of 760N was wearing the shoe and ran at 3.1mph (1.4HZ on shoe), the PFT produced an average maximum power of 2.5mW (over 2MΩ load).

  4. Dynamic analysis of rotor flex-structure based on nonlinear anisotropic shell models

    NASA Astrophysics Data System (ADS)

    Bauchau, Olivier A.; Chiang, Wuying

    1991-05-01

    In this paper an anisotropic shallow shell model is developed that accommodates transverse shearing deformations and arbitrarily large displacements and rotations, but strains are assumed to remain small. Two kinematic models are developed, the first using two DOF to locate the direction of the normal to the shell's midplane, the second using three. The latter model allows for an automatic compatibility of the shell model with beam models. The shell model is validated by comparing its predictions with several benchmark problems. In actual helicopter rotor blade problems, the shell model of the flex structure is shown to give very different results shown compared to beam models. The lead-lag and torsion modes in particular are strongly affected, whereas flapping modes seem to be less affected.

  5. Construct validity of a modification of the flexed arm hang test.

    PubMed

    Clemons, Jim M

    2014-12-01

    Despite the ubiquitous use of the flexed arm hang (FAH) as a field test of muscular fitness, evidence for the construct validity of it is lacking. The strongest validity coefficients (r) to date are 0.71 and 0.72 found by correlating modified versions of the FAH (i.e., 90 and 180° of elbow extension, respectively) with relative dynamic strength (i.e., 1 repetition maximum [1RM] lat pull downs × body mass). Considering a significant portion of all FAH and modified flexed arm hang (MFAH) performances are isometric, the test may be more correlated with the construct of relative isometric strength (RIS) rather than relative dynamic strength. The purpose of this study was to determine if the construct validity of the 90° MFAH might be strengthened by correlating it with either absolute isometric strength (AIS) (i.e., maximum volitional isometric contraction [MVIC]) or RIS (i.e., MVIC × body mass). Thirty-one college-aged women participated in the study. Inter-rater reliability coefficients for two 90° MFAH tests were determined using intraclass correlation coefficient (ICC): F1,30 = 1.356, ICC = 0.99; F1,30 = 0.675, ICC = 0.99. In addition, test-retest reliability was also found to be excellent: F1,30 = 3.809; ICC = 0.98. Pearson product moment correlation (r) was used at an adjusted alpha level of 0.025 to examine construct validity of the 90° MFAH with both AIS (MVIC) and RIS (MVIC × body mass). Results indicated no significant relationship with AIS (r = 0.096, p = 0.606); however, a strong significant relationship emerged with RIS (r = 0.878, p = 0.000). It was concluded that 90° MFAH scores alone were not related to absolute strength; however, they were found to be a valid and reliable estimate of the construct of RIS. PMID:24983850

  6. Understanding Simple Circuits

    ERIC Educational Resources Information Center

    Mant, Jenny; Wilson, Helen

    2007-01-01

    Many envisage electricity as the "power" to "do things." They know that electricity needs "circuits" and that something is "flowing" in the circuits, but they are not sure what or why. Words such as "current" and "voltage" are part of electricity but their meaning, and the difference between them, is not always clear. In this article, the authors…

  7. Liquid detection circuit

    DOEpatents

    Regan, Thomas O.

    1987-01-01

    Herein is a circuit which is capable of detecting the presence of liquids, especially cryogenic liquids, and whose sensor will not overheat in a vacuum. The circuit parameters, however, can be adjusted to work with any liquid over a wide range of temperatures.

  8. Computer circuit card puller

    NASA Technical Reports Server (NTRS)

    Sawyer, R. V.; Szuwalski, B. (Inventor)

    1981-01-01

    The invention generally relates to hand tools, and more particularly to an improved device for facilitating removal of printed circuit cards from a card rack characterized by longitudinal side rails arranged in a mutually spaced parallelism and a plurality of printed circuit cards extended between the rails of the rack.

  9. A Virtual Circuits Lab

    ERIC Educational Resources Information Center

    Vick, Matthew E.

    2010-01-01

    The University of Colorado's Physics Education Technology (PhET) website offers free, high-quality simulations of many physics experiments that can be used in the classroom. The Circuit Construction Kit, for example, allows students to safely and constructively play with circuit components while learning the mathematics behind many circuit…

  10. Genetic circuit design automation.

    PubMed

    Nielsen, Alec A K; Der, Bryan S; Shin, Jonghyeon; Vaidyanathan, Prashant; Paralanov, Vanya; Strychalski, Elizabeth A; Ross, David; Densmore, Douglas; Voigt, Christopher A

    2016-04-01

    Computation can be performed in living cells by DNA-encoded circuits that process sensory information and control biological functions. Their construction is time-intensive, requiring manual part assembly and balancing of regulator expression. We describe a design environment, Cello, in which a user writes Verilog code that is automatically transformed into a DNA sequence. Algorithms build a circuit diagram, assign and connect gates, and simulate performance. Reliable circuit design requires the insulation of gates from genetic context, so that they function identically when used in different circuits. We used Cello to design 60 circuits forEscherichia coli(880,000 base pairs of DNA), for which each DNA sequence was built as predicted by the software with no additional tuning. Of these, 45 circuits performed correctly in every output state (up to 10 regulators and 55 parts), and across all circuits 92% of the output states functioned as predicted. Design automation simplifies the incorporation of genetic circuits into biotechnology projects that require decision-making, control, sensing, or spatial organization. PMID:27034378

  11. Amplifier improvement circuit

    NASA Technical Reports Server (NTRS)

    Sturman, J.

    1968-01-01

    Stable input stage was designed for the use with a integrated circuit operational amplifier to provide improved performance as an instrumentation-type amplifier. The circuit provides high input impedance, stable gain, good common mode rejection, very low drift, and low output impedance.

  12. Parasitic suppressing circuit

    NASA Technical Reports Server (NTRS)

    Fowler, J. T.; Raposa, F. L. (Inventor)

    1973-01-01

    A circuit for suppressing parasitic oscillations across an inductor operating in a resonant mode is described. The circuit includes a switch means and resistive means connected serially across the inductor. A unidirectional resistive-capacitive network is also connected across the inductor and to the switch means to automatically render the switch means conducting when inductive current through the inductor ceases to flow.

  13. Completing a Simple Circuit.

    ERIC Educational Resources Information Center

    Slater, Timothy F.; Adams, Jeffrey P.; Brown, Thomas R.

    2000-01-01

    Students have problems successfully arranging an electric circuit to make the bulb produce light. Investigates the percentage of students able to complete a circuit with a given apparatus, and the effects of prior experience on student success. Recommends hands-on activities at the elementary and secondary school levels. (Contains 14 references.)…

  14. Differentiation and Distribution of Marrow Stem Cells in Flex-Flow Environments Demonstrate Support of the Valvular Phenotype

    PubMed Central

    Rath, Sasmita; Salinas, Manuel; Villegas, Ana G.; Ramaswamy, Sharan

    2015-01-01

    For treatment of critical heart valve diseases, prosthetic valves perform fairly well in most adults; however, for pediatric patients, there is the added requirement that the replacement valve grows with the child, thus extremely limiting current treatment options. Tissue engineered heart valves (TEHV), such as those derived from autologous bone marrow stem cells (BMSCs), have the potential to recapitulate native valve architecture and accommodate somatic growth. However, a fundamental pre-cursor in promoting directed integration with native tissues rather than random, uncontrolled growth requires an understanding of BMSC mechanobiological responses to valve-relevant mechanical environments. Here, we report on the responses of human BMSC-seeded polymer constructs to the valve-relevant stress states of: (i) steady flow alone, (ii) cyclic flexure alone, and (iii) the combination of cyclic flexure and steady flow (flex-flow). BMSCs were seeded onto a PGA: PLLA polymer scaffold and cultured in static culture for 8 days. Subsequently, the aforementioned mechanical conditions, (groups consisting of steady flow alone—850ml/min, cyclic flexure alone—1 Hz, and flex-flow—850ml/min and 1 Hz) were applied for an additional two weeks. We found samples from the flex-flow group exhibited a valve-like distribution of cells that expressed endothelial (preference to the surfaces) and myofibroblast (preference to the intermediate region) phenotypes. We interpret that this was likely due to the presence of both appreciable fluid-induced shear stress magnitudes and oscillatory shear stresses, which were concomitantly imparted onto the samples. These results indicate that flex-flow mechanical environments support directed in vitro differentiation of BMSCs uniquely towards a heart valve phenotype, as evident by cellular distribution and expression of specific gene markers. A priori guidance of BMSC-derived, engineered tissue growth under flex-flow conditions may serve to

  15. Differentiation and Distribution of Marrow Stem Cells in Flex-Flow Environments Demonstrate Support of the Valvular Phenotype.

    PubMed

    Rath, Sasmita; Salinas, Manuel; Villegas, Ana G; Ramaswamy, Sharan

    2015-01-01

    For treatment of critical heart valve diseases, prosthetic valves perform fairly well in most adults; however, for pediatric patients, there is the added requirement that the replacement valve grows with the child, thus extremely limiting current treatment options. Tissue engineered heart valves (TEHV), such as those derived from autologous bone marrow stem cells (BMSCs), have the potential to recapitulate native valve architecture and accommodate somatic growth. However, a fundamental pre-cursor in promoting directed integration with native tissues rather than random, uncontrolled growth requires an understanding of BMSC mechanobiological responses to valve-relevant mechanical environments. Here, we report on the responses of human BMSC-seeded polymer constructs to the valve-relevant stress states of: (i) steady flow alone, (ii) cyclic flexure alone, and (iii) the combination of cyclic flexure and steady flow (flex-flow). BMSCs were seeded onto a PGA: PLLA polymer scaffold and cultured in static culture for 8 days. Subsequently, the aforementioned mechanical conditions, (groups consisting of steady flow alone-850ml/min, cyclic flexure alone-1 Hz, and flex-flow-850ml/min and 1 Hz) were applied for an additional two weeks. We found samples from the flex-flow group exhibited a valve-like distribution of cells that expressed endothelial (preference to the surfaces) and myofibroblast (preference to the intermediate region) phenotypes. We interpret that this was likely due to the presence of both appreciable fluid-induced shear stress magnitudes and oscillatory shear stresses, which were concomitantly imparted onto the samples. These results indicate that flex-flow mechanical environments support directed in vitro differentiation of BMSCs uniquely towards a heart valve phenotype, as evident by cellular distribution and expression of specific gene markers. A priori guidance of BMSC-derived, engineered tissue growth under flex-flow conditions may serve to subsequently

  16. From Local to EXtreme Environments (FLEXE): Promoting Earth Systems Science Literacy Through Student Inquiry and Real Data

    NASA Astrophysics Data System (ADS)

    Goehring, E. C.; Carlsen, W.; Larsen, J.; Simms, E.; Smith, M.

    2007-12-01

    From Local to EXtreme Environments (FLEXE) is an innovative new project of the GLOBE Program that involves middle and high school students in systematic, facilitated analyses and comparisons of real environmental data. Through FLEXE, students collect and analyze data from various sources, including the multi-year GLOBE database, deep-sea scientific research projects, and direct measurements of the local environment collected by students using GLOBE sampling protocols. Initial FLEXE materials and training have focused on student understanding of energy transfer through components of the Earth system, including a comparison of how local environmental conditions differ from those found at deep-sea hydrothermal vent communities. While the importance of data acquisition, accuracy and replication is emphasized, FLEXE is also uniquely structured to deepen students' understanding of multiple aspects of the process and nature of science, including written communication of results and on-line peer review. Analyses of data are facilitated through structured, web-based interactions and culminating activities with at-sea scientists through an online forum. The project benefits from the involvement of a professional evaluator, and as the model is tested and refined, it may serve as a template for the inclusion of additional "extreme" earth systems. FLEXE is a partnership of the international GLOBE web- based education program and the NSF Ridge 2000 mid-ocean ridge and hydrothermal vent research program, and includes the expertise of the Center for Science and the Schools at Penn State University. International collaborators also include the InterRidge and ChEss international research programs.

  17. Thermocouple-Signal-Conditioning Circuit

    NASA Technical Reports Server (NTRS)

    Simon, Richard A.

    1991-01-01

    Thermocouple-signal-conditioning circuit acting in conjunction with thermocouple, exhibits electrical behavior of voltage in series with resistance. Combination part of input bridge circuit of controller. Circuit configured for either of two specific applications by selection of alternative resistances and supply voltages. Includes alarm circuit detecting open circuit in thermocouple and provides off-scale output to signal malfunctions.

  18. Compensated gain control circuit for buck regulator command charge circuit

    DOEpatents

    Barrett, David M.

    1996-01-01

    A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit.

  19. Compensated gain control circuit for buck regulator command charge circuit

    DOEpatents

    Barrett, D.M.

    1996-11-05

    A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit. 5 figs.

  20. A Comparison of Performance of Endotracheal Intubation Using the Levitan FPS Optical Stylet or Lary-Flex Videolaryngoscope in Morbidly Obese Patients

    PubMed Central

    Szewczyk, Tomasz; Gaszynska, Ewelina

    2014-01-01

    Introduction. The use of videolaryngoscopes is recommended for morbidly obese patients. The aim of the study was to evaluate the Levitan FPS optical stylet (Levitan) vs Lafy-Flex videolaryngoscope (Lary-Flex) in a group of MO patients. Methods. Seventy-nine MO (BMI > 40 kg m−2) patients scheduled for bariatric surgery were included in the study and randomly allocated to the Levitan FPS or Lary-Flex group. The primary endpoint was time to intubation and evaluation laryngoscopic of glottic view. Anesthesiologists were asked to evaluate the glottic view first under direct laryngoscopy using the videolaryngoscope as a standard laryngoscope (monitor display was excluded from use) and then using devices. The secondary endpoint was the cardiovascular response to intubation and the participant's evaluation of such devices. Results. The time to intubation was 8.572.66 sec. versus 5.790.2 sec. for Levitan and Lary-Flex, respectively (P < 0.05). In all cases of CL grade >1 under direct laryngoscopy, the study devices improved CL grade to 1. The Levitan FPS produced a greater cardiovascular response than the Lary-Flex videolaryngoscope. Conclusion. The Lary-Flex videolaryngoscope and the Levitan FPS optical stylet improve the laryngeal visualization in morbidly obese patients, allowing for fast endotracheal intubation, but Lary-Flex produces less cardiovascular response to intubation attempt. PMID:24967423

  1. Sensor readout detector circuit

    DOEpatents

    Chu, D.D.; Thelen, D.C. Jr.

    1998-08-11

    A sensor readout detector circuit is disclosed that is capable of detecting sensor signals down to a few nanoamperes or less in a high (microampere) background noise level. The circuit operates at a very low standby power level and is triggerable by a sensor event signal that is above a predetermined threshold level. A plurality of sensor readout detector circuits can be formed on a substrate as an integrated circuit (IC). These circuits can operate to process data from an array of sensors in parallel, with only data from active sensors being processed for digitization and analysis. This allows the IC to operate at a low power level with a high data throughput for the active sensors. The circuit may be used with many different types of sensors, including photodetectors, capacitance sensors, chemically-sensitive sensors or combinations thereof to provide a capability for recording transient events or for recording data for a predetermined period of time following an event trigger. The sensor readout detector circuit has applications for portable or satellite-based sensor systems. 6 figs.

  2. Sensor readout detector circuit

    DOEpatents

    Chu, Dahlon D.; Thelen, Jr., Donald C.

    1998-01-01

    A sensor readout detector circuit is disclosed that is capable of detecting sensor signals down to a few nanoamperes or less in a high (microampere) background noise level. The circuit operates at a very low standby power level and is triggerable by a sensor event signal that is above a predetermined threshold level. A plurality of sensor readout detector circuits can be formed on a substrate as an integrated circuit (IC). These circuits can operate to process data from an array of sensors in parallel, with only data from active sensors being processed for digitization and analysis. This allows the IC to operate at a low power level with a high data throughput for the active sensors. The circuit may be used with many different types of sensors, including photodetectors, capacitance sensors, chemically-sensitive sensors or combinations thereof to provide a capability for recording transient events or for recording data for a predetermined period of time following an event trigger. The sensor readout detector circuit has applications for portable or satellite-based sensor systems.

  3. Polymorphic Electronic Circuits

    NASA Technical Reports Server (NTRS)

    Stoica, Adrian

    2004-01-01

    Polymorphic electronics is a nascent technological discipline that involves, among other things, designing the same circuit to perform different analog and/or digital functions under different conditions. For example, a circuit can be designed to function as an OR gate or an AND gate, depending on the temperature (see figure). Polymorphic electronics can also be considered a subset of polytronics, which is a broader technological discipline in which optical and possibly other information- processing systems could also be designed to perform multiple functions. Polytronics is an outgrowth of evolvable hardware (EHW). The basic concepts and some specific implementations of EHW were described in a number of previous NASA Tech Briefs articles. To recapitulate: The essence of EHW is to design, construct, and test a sequence of populations of circuits that function as incrementally better solutions of a given design problem through the selective, repetitive connection and/or disconnection of capacitors, transistors, amplifiers, inverters, and/or other circuit building blocks. The evolution is guided by a search-and-optimization algorithm (in particular, a genetic algorithm) that operates in the space of possible circuits to find a circuit that exhibits an acceptably close approximation of the desired functionality. The evolved circuits can be tested by computational simulation (in which case the evolution is said to be extrinsic), tested in real hardware (in which case the evolution is said to be intrinsic), or tested in random sequences of computational simulation and real hardware (in which case the evolution is said to be mixtrinsic).

  4. Approximate circuits for increased reliability

    SciTech Connect

    Hamlet, Jason R.; Mayo, Jackson R.

    2015-08-18

    Embodiments of the invention describe a Boolean circuit having a voter circuit and a plurality of approximate circuits each based, at least in part, on a reference circuit. The approximate circuits are each to generate one or more output signals based on values of received input signals. The voter circuit is to receive the one or more output signals generated by each of the approximate circuits, and is to output one or more signals corresponding to a majority value of the received signals. At least some of the approximate circuits are to generate an output value different than the reference circuit for one or more input signal values; however, for each possible input signal value, the majority values of the one or more output signals generated by the approximate circuits and received by the voter circuit correspond to output signal result values of the reference circuit.

  5. Approximate circuits for increased reliability

    SciTech Connect

    Hamlet, Jason R.; Mayo, Jackson R.

    2015-12-22

    Embodiments of the invention describe a Boolean circuit having a voter circuit and a plurality of approximate circuits each based, at least in part, on a reference circuit. The approximate circuits are each to generate one or more output signals based on values of received input signals. The voter circuit is to receive the one or more output signals generated by each of the approximate circuits, and is to output one or more signals corresponding to a majority value of the received signals. At least some of the approximate circuits are to generate an output value different than the reference circuit for one or more input signal values; however, for each possible input signal value, the majority values of the one or more output signals generated by the approximate circuits and received by the voter circuit correspond to output signal result values of the reference circuit.

  6. Gallium Arsenide Domino Circuit

    NASA Technical Reports Server (NTRS)

    Yang, Long; Long, Stephen I.

    1990-01-01

    Advantages include reduced power and high speed. Experimental gallium arsenide field-effect-transistor (FET) domino circuit replicated in large numbers for use in dynamic-logic systems. Name of circuit denotes mode of operation, which logic signals propagate from each stage to next when successive stages operated at slightly staggered clock cycles, in manner reminiscent of dominoes falling in a row. Building block of domino circuit includes input, inverter, and level-shifting substages. Combinational logic executed in input substage. During low half of clock cycle, result of logic operation transmitted to following stage.

  7. DIFFERENTIAL FAULT SENSING CIRCUIT

    DOEpatents

    Roberts, J.H.

    1961-09-01

    A differential fault sensing circuit is designed for detecting arcing in high-voltage vacuum tubes arranged in parallel. A circuit is provided which senses differences in voltages appearing between corresponding elements likely to fault. Sensitivity of the circuit is adjusted to some level above which arcing will cause detectable differences in voltage. For particular corresponding elements, a group of pulse transformers are connected in parallel with diodes connected across the secondaries thereof so that only voltage excursions are transmitted to a thyratron which is biased to the sensitivity level mentioned.

  8. Power supply conditioning circuit

    NASA Technical Reports Server (NTRS)

    Primas, Lori E. (Inventor); Loveland, Rohan C. (Inventor)

    1988-01-01

    A conditioning circuit is provided with a constant current diode in series with a zener diode, the former having a high dynamic impedance and the latter a low dynamic impedance. The constant current diode can receive an input voltage with PARD. In conjunction with the zener diode fixed to a ground, a voltage divider is provided which can give an output voltage whose PARD was significantly reduced. The conditioning circuit is effective down to dc.

  9. Summary of Results Obtained in Full-Scale Tunnel Investigation of the Ryan Flex-Wing Airplane

    NASA Technical Reports Server (NTRS)

    Johnson, Joseph L., Jr.; Hassell, James L., Jr.

    1962-01-01

    The performance and static stability and control characteristics of the Ryan Flex-Wing airplane were determined in an investigation conducted in the Langley full-scale tunnel through an angle-of-attack range of the keel from about 14 to 44 deg. for power-on and -off conditions. Comparisons of the wind-tunnel data with flight-test data obtained with the same airplane by the Ryan Aeronautical Company were made in a number of cases.

  10. A new twist on gyroscopic sensing: body rotations lead to torsion in flapping, flexing insect wings.

    PubMed

    Eberle, A L; Dickerson, B H; Reinhall, P G; Daniel, T L

    2015-03-01

    Insects perform fast rotational manoeuvres during flight. While two insect orders use flapping halteres (specialized organs evolved from wings) to detect body dynamics, it is unknown how other insects detect rotational motions. Like halteres, insect wings experience gyroscopic forces when they are flapped and rotated and recent evidence suggests that wings might indeed mediate reflexes to body rotations. But, can gyroscopic forces be detected using only changes in the structural dynamics of a flapping, flexing insect wing? We built computational and robotic models to rotate a flapping wing about an axis orthogonal to flapping. We recorded high-speed video of the model wing, which had a flexural stiffness similar to the wing of the Manduca sexta hawkmoth, while flapping it at the wingbeat frequency of Manduca (25 Hz). We compared the three-dimensional structural dynamics of the wing with and without a 3 Hz, 10° rotation about the yaw axis. Our computational model revealed that body rotation induces a new dynamic mode: torsion. We verified our result by measuring wing tip displacement, shear strain and normal strain of the robotic wing. The strains we observed could stimulate an insect's mechanoreceptors and trigger reflexive responses to body rotations. PMID:25631565

  11. A new twist on gyroscopic sensing: body rotations lead to torsion in flapping, flexing insect wings

    PubMed Central

    Eberle, A. L.; Dickerson, B. H.; Reinhall, P. G.; Daniel, T. L.

    2015-01-01

    Insects perform fast rotational manoeuvres during flight. While two insect orders use flapping halteres (specialized organs evolved from wings) to detect body dynamics, it is unknown how other insects detect rotational motions. Like halteres, insect wings experience gyroscopic forces when they are flapped and rotated and recent evidence suggests that wings might indeed mediate reflexes to body rotations. But, can gyroscopic forces be detected using only changes in the structural dynamics of a flapping, flexing insect wing? We built computational and robotic models to rotate a flapping wing about an axis orthogonal to flapping. We recorded high-speed video of the model wing, which had a flexural stiffness similar to the wing of the Manduca sexta hawkmoth, while flapping it at the wingbeat frequency of Manduca (25 Hz). We compared the three-dimensional structural dynamics of the wing with and without a 3 Hz, 10° rotation about the yaw axis. Our computational model revealed that body rotation induces a new dynamic mode: torsion. We verified our result by measuring wing tip displacement, shear strain and normal strain of the robotic wing. The strains we observed could stimulate an insect's mechanoreceptors and trigger reflexive responses to body rotations. PMID:25631565

  12. Evaluation of candidate alloys for the construction of metal flex hoses in the STS launch environment

    NASA Technical Reports Server (NTRS)

    Ontiveros, Cordelia

    1988-01-01

    Various vacuum jacketed cryogenic supply lines at the Shuttle launch site use convoluted flexible expansion joints. The atmosphere at the launch site has a very high salt content, and during a launch, fuel combustion products include hydrochloric acid. This extremely corrosive environment has caused pitting corrosion failure in the flex hoses, which were made of 304L stainless steel. A search was done to find a more corrosion resistant replacement material. This study focused on 19 metal alloys. Tests which were performed include electrochemical corrosion testing, accelerated corrosion testing in a salt fog chamber, long term exposure at the beach corrosion testing site, and pitting corrosion tests in ferric chloride solution. Based on the results of these tests, the most corrosion resistant alloys were found to be (in order) Hastelloy C-22, Inconel 625, Hastelloy C-276, Hastelloy C-4, and Inco Alloy G-3. Of these top five alloys, the Hastelloy C-22 stands out as being the best of those tested for this application.

  13. Parker Flex-Tip and Standard-Tip Endotracheal Tubes: A Comparison During Nasotracheal Intubation

    PubMed Central

    Prior, Simon; Heaton, Jarom; Jatana, Kris R.; Rashid, Robert G.

    2010-01-01

    Abstract The placement of endotracheal tubes in the airway, particularly through the nose, can cause trauma. Their design might be an important etiologic factor, but they have changed little since their introduction. Recently Parker Medical (Bridgewater, Conn ) introduced the Parker Flex-Tip (PFT) tube, suggesting that it causes less trauma. This study aimed to compare the PFT endotracheal tube to a side-beveled, standard-tip endotracheal tube (ETT) for nasotracheal intubation (Figures 1 and 2). Forty consecutive oral surgery patients requiring nasotracheal intubation were randomized to receive either a standard ETT or the PFT tube. Intubations were recorded using a fiber-optic camera positioned proximal to the Murphy eye of the tube. This allowed visualization of the path and action of the tube tip as it traversed the nasal, pharyngeal, laryngeal, and tracheal airway regions. Video recordings made during intubation and extubation were evaluated for bleeding, trauma, and intubation time. Both bleeding and trauma were recorded using a visual analogue scale (VAS) and by 3 different evaluators. The PFT received significantly better VAS values than the standard tubes from all 3 raters (P < 0.05) in both the extent of trauma and bleeding. Since the intubations were purposefully conducted slowly for photographic reasons, neither tube displayed a time advantage. This study suggests that the PFT tube design may be safer by causing less trauma and bleeding than standard tube designs for nasotracheal intubation. PMID:20331335

  14. Circuit simulation: some humbling thoughts

    SciTech Connect

    Wendt, Manfred; /Fermilab

    2006-01-01

    A short, very personal note on circuit simulation is presented. It does neither include theoretical background on circuit simulation, nor offers an overview of available software, but just gives some general remarks for a discussion on circuit simulator needs in context to the design and development of accelerator beam instrumentation circuits and systems.

  15. Superconducting flux flow digital circuits

    DOEpatents

    Hietala, V.M.; Martens, J.S.; Zipperian, T.E.

    1995-02-14

    A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs) are disclosed. Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics. 8 figs.

  16. Superconducting flux flow digital circuits

    DOEpatents

    Hietala, Vincent M.; Martens, Jon S.; Zipperian, Thomas E.

    1995-01-01

    A NOR/inverter logic gate circuit and a flip flop circuit implemented with superconducting flux flow transistors (SFFTs). Both circuits comprise two SFFTs with feedback lines. They have extremely low power dissipation, very high switching speeds, and the ability to interface between Josephson junction superconductor circuits and conventional microelectronics.

  17. Parker Flex-It stylet is as effective as GlideRite Rigid stylet for orotracheal intubation by Glidescope

    PubMed Central

    Sheta, Saad A.; Abdelhalim, Ashraf A.; ElZoughari, Ismail A.; AlZahrani, Tariq A.; Al-Saeed, Abdulhamid H.

    2015-01-01

    Objectives: To evaluate Parker Flex-It stylet as an alternative to GlideRite Rigid stylet to aid tracheal intubation with the Glidescope. Methods: This prospective randomized trial was conducted at King Abdulaziz University Hospital, College of Medicine, King Saud University, Riyadh, Saudi Arabia between May and December 2014. Sixty American Society of Anesthesiologists I-II patients were randomly assigned to one of 2 equal groups receiving intubation by Glidescope using either GlideRite Rigid stylet (Group GS) or Parker Flex-It stylet (Group PS). The total intubation time, ease of intubation, incidences of successful intubation at first attempt, number of intubation attempts, use of optimization maneuvers, and possible complications were recorded. Results: No significant differences between both groups regarding the total intubation time (p=0.08) was observed. Intubation was significantly easier in group PS compared with group GS as measured by visual analogue scale (p=0.001) with no significant differences between the groups regarding the rate of successful tracheal intubation from first attempt (p=0.524). However, the number of attempts at intubation and usage of external laryngeal manipulation were similar in both groups (p>0.05). The incidence of sore throat, dysphagia, hoarseness, and trauma were significantly higher in group GS (p<0.05). Conclusion: Parker Flex-It stylet is as effective as GlideRite Rigid stylet when used by experienced operators in patients with normal airways using Glidescope; however, it is easier and less traumatic. PMID:26620987

  18. Manufacturing Cost Analysis for YSZ-Based FlexCells at Pilot and Full Scale Production Scales

    SciTech Connect

    Scott Swartz; Lora Thrun; Robin Kimbrell; Kellie Chenault

    2011-05-01

    Significant reductions in cell costs must be achieved in order to realize the full commercial potential of megawatt-scale SOFC power systems. The FlexCell designed by NexTech Materials is a scalable SOFC technology that offers particular advantages over competitive technologies. In this updated topical report, NexTech analyzes its FlexCell design and fabrication process to establish manufacturing costs at both pilot scale (10 MW/year) and full-scale (250 MW/year) production levels and benchmarks this against estimated anode supported cell costs at the 250 MW scale. This analysis will show that even with conservative assumptions for yield, materials usage, and cell power density, a cost of $35 per kilowatt can be achieved at high volume. Through advancements in cell size and membrane thickness, NexTech has identified paths for achieving cell manufacturing costs as low as $27 per kilowatt for its FlexCell technology. Also in this report, NexTech analyzes the impact of raw material costs on cell cost, showing the significant increases that result if target raw material costs cannot be achieved at this volume.

  19. Liver acquisition with volume acceleration flex on 70-cm wide-bore and 60-cm conventional-bore 3.0-T MRI.

    PubMed

    Saito, Shigeyoshi; Tanaka, Keiko; Hashido, Takashi

    2016-07-01

    This study aimed to compare the uniformity of fat suppression and image quality between liver acquisition with volume acceleration flex (LAVA-Flex) and LAVA on 60-cm conventional-bore and 70-cm wide-bore 3.0-T magnetic resonance imaging (MRI). The uniformity of fat suppression by LAVA-Flex and LAVA was assessed as the efficiency of suppression of superficial fat at the levels of the liver dome, porta, and renal hilum. Percentage standard deviation (%SD) was calculated using the following equation: %SD (%) = 100 × SD of the regions of interest (ROIs)/mean value of the signal intensity (SI) in the ROIs. Signal-to-noise ratio (SNR) and contrast ratio (CR) were calculated. In the LAVA sequence, the %SD in all slices on wide-bore 3.0-T MRI was significantly higher than that on conventional-bore 3.0-T MRI (P < 0.01). However, there was no significant difference in fat signal uniformity between the conventional and wide-bore scanners when LAVA-Flex was used. In the liver, there were no significant differences in SNR between the two sequences. However, the SNR in the pancreas was lower for the wide-bore scanner than for the conventional-bore scanner for both sequences (P < 0.05). There were no significant differences in CR for the liver and fat between LAVA-Flex and LAVA in both scanners. The CR in the LAVA-Flex images obtained by wide-bore MRI was significantly higher than that in the LAVA-Flex images recorded by conventional-bore MRI (P < 0.001). LAVA-Flex offers more homogenous fat suppression in the upper abdomen than LAVA for both conventional and wide-bore 3.0-T MRI. PMID:26739299

  20. Comparison of the shaping ability of RaCe and FlexMaster rotary nickel-titanium systems in simulated canals.

    PubMed

    Merrett, Sarah J; Bryant, Susan T; Dummer, Paul M H

    2006-10-01

    The aim of this study was to compare the shaping ability of RaCe and FlexMaster rotary nickel-titanium instruments in simulated canals. A total of 80 canals with four different shapes were prepared with either RaCe or FlexMaster instruments. Pre- and postoperative images of each canal were recorded and combined using image analysis software. The development of canal aberrations and transportation was assessed. There was a significant difference (p < 0.001) between the systems for time of preparation to apical size 30, .06 taper; FlexMaster instruments took on average 1.86 min and RaCe 1.66 min. One RaCe and two FlexMaster instruments fractured. No zips, elbows, or danger zones were created. One perforation and eight outer widenings were created using FlexMaster instruments; RaCe instruments created two outer widenings. No differences were found between the instruments for direction of transportation. RaCe and FlexMaster nickel-titanium instruments prepared canals rapidly with few aberrations. PMID:16982273

  1. ELECTRONIC MULTIPLIER CIRCUIT

    DOEpatents

    Thomas, R.E.

    1959-08-25

    An electronic multiplier circuit is described in which an output voltage having an amplitude proportional to the product or quotient of the input signals is accomplished in a novel manner which facilitates simplicity of circuit construction and a high degree of accuracy in accomplishing the multiplying and dividing function. The circuit broadly comprises a multiplier tube in which the plate current is proportional to the voltage applied to a first control grid multiplied by the difference between voltage applied to a second control grid and the voltage applied to the first control grid. Means are provided to apply a first signal to be multiplied to the first control grid together with means for applying the sum of the first signal to be multiplied and a second signal to be multiplied to the second control grid whereby the plate current of the multiplier tube is proportional to the product of the first and second signals to be multiplied.

  2. ELECTRONIC TRIGGER CIRCUIT

    DOEpatents

    Russell, J.A.G.

    1958-01-01

    An electronic trigger circuit is described of the type where an output pulse is obtained only after an input voltage has cqualed or exceeded a selected reference voltage. In general, the invention comprises a source of direct current reference voltage in series with an impedance and a diode rectifying element. An input pulse of preselected amplitude causes the diode to conduct and develop a signal across the impedance. The signal is delivered to an amplifier where an output pulse is produced and part of the output is fed back in a positive manner to the diode so that the amplifier produces a steep wave front trigger pulsc at the output. The trigger point of the described circuit is not subject to variation due to the aging, etc., of multi-electrode tabes, since the diode circuit essentially determines the trigger point.

  3. Logsum Using Garbled Circuits

    PubMed Central

    Portêlo, José; Raj, Bhiksha; Trancoso, Isabel

    2015-01-01

    Secure multiparty computation allows for a set of users to evaluate a particular function over their inputs without revealing the information they possess to each other. Theoretically, this can be achieved using fully homomorphic encryption systems, but so far they remain in the realm of computational impracticability. An alternative is to consider secure function evaluation using homomorphic public-key cryptosystems or Garbled Circuits, the latter being a popular trend in recent times due to important breakthroughs. We propose a technique for computing the logsum operation using Garbled Circuits. This technique relies on replacing the logsum operation with an equivalent piecewise linear approximation, taking advantage of recent advances in efficient methods for both designing and implementing Garbled Circuits. We elaborate on how all the required blocks should be assembled in order to obtain small errors regarding the original logsum operation and very fast execution times. PMID:25811740

  4. ELECTRONIC PHASE CONTROL CIRCUIT

    DOEpatents

    Salisbury, J.D.; Klein, W.W.; Hansen, C.F.

    1959-04-21

    An electronic circuit is described for controlling the phase of radio frequency energy applied to a multicavity linear accelerator. In one application of the circuit two cavities are excited from a single radio frequency source, with one cavity directly coupled to the source and the other cavity coupled through a delay line of special construction. A phase detector provides a bipolar d-c output signal proportional to the difference in phase between the voltage in the two cavities. This d-c signal controls a bias supply which provides a d-c output for varying the capacitnce of voltage sensitive capacitors in the delay line. The over-all operation of the circuit is completely electronic, overcoming the time response limitations of the electromechanical control systems, and the relative phase relationship of the radio frequency voltages in the two caviiies is continuously controlled to effect particle acceleration.

  5. Picosecond Imaging Circuit Analysis

    NASA Astrophysics Data System (ADS)

    Kash, Jeffrey A.

    1998-03-01

    With ever-increasing complexity, probing the internal operation of a silicon IC becomes more challenging. Present methods of internal probing are becoming obsolete. We have discovered that a very weak picosecond pulse of light is emitted by each FET in a CMOS circuit whenever the circuit changes logic state. This pulsed emission can be simultaneously imaged and time resolved, using a technique we have named Picosecond Imaging Circuit Analysis (PICA). With a suitable imaging detector, PICA allows time resolved measurement on thousands of devices simultaneously. Computer videos made from measurements on real IC's will be shown. These videos, along with a more quantitative evaluation of the light emission, permit the complete operation of an IC to be measured in a non-invasive way with picosecond time resolution.

  6. Inrush Current Control Circuit

    NASA Technical Reports Server (NTRS)

    Cole, Steven W. (Inventor)

    2002-01-01

    An inrush current control circuit having an input terminal connected to a DC power supply and an output terminal connected to a load capacitor limits the inrush current that charges up the load capacitor during power up of a system. When the DC power supply applies a DC voltage to the input terminal, the inrush current control circuit produces a voltage ramp at the load capacitor instead of an abrupt DC voltage. The voltage ramp results in a constant low level current to charge up the load capacitor, greatly reducing the current drain on the DC power supply.

  7. Electrical Circuit Tester

    DOEpatents

    Love, Frank

    2006-04-18

    An electrical circuit testing device is provided, comprising a case, a digital voltage level testing circuit with a display means, a switch to initiate measurement using the device, a non-shorting switching means for selecting pre-determined electrical wiring configurations to be tested in an outlet, a terminal block, a five-pole electrical plug mounted on the case surface and a set of adapters that can be used for various multiple-pronged electrical outlet configurations for voltages from 100 600 VAC from 50 100 Hz.

  8. Small circuits for cryptography.

    SciTech Connect

    Torgerson, Mark Dolan; Draelos, Timothy John; Schroeppel, Richard Crabtree; Miller, Russell D.; Anderson, William Erik

    2005-10-01

    This report examines a number of hardware circuit design issues associated with implementing certain functions in FPGA and ASIC technologies. Here we show circuit designs for AES and SHA-1 that have an extremely small hardware footprint, yet show reasonably good performance characteristics as compared to the state of the art designs found in the literature. Our AES performance numbers are fueled by an optimized composite field S-box design for the Stratix chipset. Our SHA-1 designs use register packing and feedback functionalities of the Stratix LE, which reduce the logic element usage by as much as 72% as compared to other SHA-1 designs.

  9. Micromachined Silicon Waveguide Circuits

    NASA Technical Reports Server (NTRS)

    McGrath, W. R.

    1995-01-01

    Rectangular waveguides are commonly used as circuit elements in remote-sensing heterodyne receivers at millimeter wavelengths. The advantages of waveguides are low loss and mechanical tunability. However, conventional machining techniques for waveguide components operating above a few hundred GHz are complicated and costly. Waveguides micromachined from silicon however would have several important advantages including low-cost; small size for very high frequency (submillimeter wave) operation; high dimensional accuracy (important for high-Q circuits); atomically smooth walls, thereby reducing rf losses; and the ability to integrate active and passive devices directly in the waveguide on thin membranes, thereby solving the traditional problem of mounting thin substrates.

  10. High transmission 3D printed flex-PCB-based ion funnel.

    PubMed

    Tridas, Eric Miguel; Allemang, Christopher; Mast, Fabian; Anthony, J Mark; Schlaf, Rudiger

    2015-07-01

    In this study a novel fabrication method for a radio frequency (RF) ion funnel is presented. RF ion funnels are important devices for focusing ion clouds at low vacuum conditions for mass spectrometry or deposition-related applications. Typically, ion funnels are constructed of stainless steel plate ring electrodes with a decreasing diameter where RF and direct current potentials are applied to the electrodes to focus the ion cloud. The presented novel design is based on a flexible circuit board that serves both as the signal distribution circuit and as the electrodes of the ion funnel. The flexible circuit board is rolled into a 3D printed scaffold to create a funnel shape with ring electrodes formed by the copper electrodes of the flexible circuit board. The design is characterized in direct comparison with a conventional steel-plate electrode design. The discussed results show that the new funnel has similar performance to the conventionally designed funnel despite much lower manufacturing costs. PMID:26349649

  11. Bioluminescent bioreporter integrated circuit

    DOEpatents

    Simpson, Michael L.; Sayler, Gary S.; Paulus, Michael J.

    2000-01-01

    Disclosed are monolithic bioelectronic devices comprising a bioreporter and an OASIC. These bioluminescent bioreporter integrated circuit are useful in detecting substances such as pollutants, explosives, and heavy-metals residing in inhospitable areas such as groundwater, industrial process vessels, and battlefields. Also disclosed are methods and apparatus for environmental pollutant detection, oil exploration, drug discovery, industrial process control, and hazardous chemical monitoring.

  12. The Global Circuit.

    ERIC Educational Resources Information Center

    Lansford, Henry

    1983-01-01

    Discusses the nature of and research related to a theory explaining the earth's electric budget. The theory suggests a global electric circuit completed by a positive current flowing up into thunderstorm clouds, from clouds to ionosphere, distributed around the globe, and down to earth through the lower atmosphere in fair-weather regions. (JN)

  13. A Step Circuit Program.

    ERIC Educational Resources Information Center

    Herman, Susan

    1995-01-01

    Aerobics instructors can use step aerobics to motivate students. One creative method is to add the step to the circuit workout. By incorporating the step, aerobic instructors can accommodate various fitness levels. The article explains necessary equipment and procedures, describing sample stations for cardiorespiratory fitness, muscular strength,…

  14. Circuit breaker lockout device

    DOEpatents

    Kozlowski, L.J.; Shirey, L.A.

    1992-11-24

    An improved lockout assembly for locking a circuit breaker in a selected off or on position is provided. The lockout assembly includes a lock block and a lock pin. The lock block has a hollow interior which fits over the free end of a switch handle of the circuit breaker. The lock block includes at least one hole that is placed in registration with a hole in the free end of the switch handle. A lock tab on the lock block serves to align and register the respective holes on the lock block and switch handle. A lock pin is inserted through the registered holes and serves to connect the lock block to the switch handle. Once the lock block and the switch handle are connected, the position of the switch handle is prevented from being changed by the lock tab bumping up against a stationary housing portion of the circuit breaker. When the lock pin installed, an apertured-end portion of the lock pin is in registration with another hole on the lock block. Then a special scissors conforming to O.S.H.A. regulations can be installed, with one or more padlocks, on the lockout assembly to prevent removal of the lock pin from the lockout assembly, thereby preventing removal of the lockout assembly from the circuit breaker. 2 figs.

  15. Circuit breaker lockout device

    DOEpatents

    Kozlowski, Lawrence J.; Shirey, Lawrence A.

    1992-01-01

    An improved lockout assembly for locking a circuit breaker in a selected off or on position is provided. The lockout assembly includes a lock block and a lock pin. The lock block has a hollow interior which fits over the free end of a switch handle of the circuit breaker. The lock block includes at least one hole that is placed in registration with a hole in the free end of the switch handle. A lock tab on the lock block serves to align and register the respective holes on the lock block and switch handle. A lock pin is inserted through the registered holes and serves to connect the lock block to the switch handle. Once the lock block and the switch handle are connected, the position of the switch handle is prevented from being changed by the lock tab bumping up against a stationary housing portion of the circuit breaker. When the lock pin installed, an apertured-end portion of the lock pin is in registration with another hole on the lock block. Then a special scissors conforming to O.S.H.A. regulations can be installed, with one or more padlocks, on the lockout assembly to prevent removal of the lock pin from the lockout assembly, thereby preventing removal of the lockout assembly from the circuit breaker.

  16. Energy management circuit

    SciTech Connect

    Corless, R. W.

    1985-10-15

    An energy management circuit for use in a telephone or other device which includes an electronic memory is disclosed. The invention provides a capacitive keep alive power supply to maintain said memory in an active condition during extended periods when the device is disconnected from a line power source, as in a telephone on-hook condition. A large capacitor charge is maintained within a predetermined voltage range during such disconnect conditions by a resistively coupled trickle charge power source. A comparator is operated to monitor capacitor charge and to produce a control signal when the voltage at the capacitor falls below a selected memory keep alive level. The control signal operates a switch to bypass the trickle charge circuit. The switch couples line power directly to the capacitor to charge the capacitor to a voltage sufficient to maintain memory contents intact. A switch inhibit circuit is provided to prevent trickle charge bypass during an inadequate or excessive line voltage condition. A sleep timer circuit is also provided to conserve energy required to operate the present invention by allowing the invention to operate periodically and only for short intervals.

  17. Automatic sweep circuit

    DOEpatents

    Keefe, Donald J.

    1980-01-01

    An automatically sweeping circuit for searching for an evoked response in an output signal in time with respect to a trigger input. Digital counters are used to activate a detector at precise intervals, and monitoring is repeated for statistical accuracy. If the response is not found then a different time window is examined until the signal is found.

  18. "Printed-circuit" rectenna

    NASA Technical Reports Server (NTRS)

    Dickinson, R. M.

    1977-01-01

    Rectifying antenna is less bulky structure for absorbing transmitted microwave power and converting it into electrical current. Printed-circuit approach, using microstrip technology and circularly polarized antenna, makes polarization orientation unimportant and allows much smaller arrays for given performance. Innovation is particularly useful with proposed electric vehicles powered by beam microwaves.

  19. A coherent RC circuit

    NASA Astrophysics Data System (ADS)

    Gabelli, J.; Fève, G.; Berroir, J.-M.; Plaçais, B.

    2012-12-01

    We review the first experiment on dynamic transport in a phase-coherent quantum conductor. In our discussion, we highlight the use of time-dependent transport as a means of gaining insight into charge relaxation on a mesoscopic scale. For this purpose, we studied the ac conductance of a model quantum conductor, i.e. the quantum RC circuit. Prior to our experimental work, Büttiker et al (1993 Phys. Lett. A 180 364-9) first worked on dynamic mesoscopic transport in the 1990s. They predicted that the mesoscopic RC circuit can be described by a quantum capacitance related to the density of states in the capacitor and a constant charge-relaxation resistance equal to half of the resistance quantum h/2e2, when a single mode is transmitted between the capacitance and a reservoir. By applying a microwave excitation to a gate located on top of a coherent submicronic quantum dot that is coupled to a reservoir, we validate this theoretical prediction on the ac conductance of the quantum RC circuit. Our study demonstrates that the ac conductance is directly related to the dwell time of electrons in the capacitor. Thereby, we observed a counterintuitive behavior of a quantum origin: as the transmission of the single conducting mode decreases, the resistance of the quantum RC circuit remains constant while the capacitance oscillates.

  20. Electrifying Inquiry: Electrical Circuits

    ERIC Educational Resources Information Center

    Godbey, Susan; Barnett, Jessica; Webster, Lois

    2005-01-01

    An activity involving parallel electrical circuits was modified to incorporate an open inquiry approach. Both the original and revised versions of the activity were tested in the middle school classroom. We present a comparison of the two versions of the activity in terms of facilitating learning and engaging students' interests.

  1. Integrated circuit reliability testing

    NASA Technical Reports Server (NTRS)

    Buehler, Martin G. (Inventor); Sayah, Hoshyar R. (Inventor)

    1990-01-01

    A technique is described for use in determining the reliability of microscopic conductors deposited on an uneven surface of an integrated circuit device. A wafer containing integrated circuit chips is formed with a test area having regions of different heights. At the time the conductors are formed on the chip areas of the wafer, an elongated serpentine assay conductor is deposited on the test area so the assay conductor extends over multiple steps between regions of different heights. Also, a first test conductor is deposited in the test area upon a uniform region of first height, and a second test conductor is deposited in the test area upon a uniform region of second height. The occurrence of high resistances at the steps between regions of different height is indicated by deriving the measured length of the serpentine conductor using the resistance measured between the ends of the serpentine conductor, and comparing that to the design length of the serpentine conductor. The percentage by which the measured length exceeds the design length, at which the integrated circuit will be discarded, depends on the required reliability of the integrated circuit.

  2. Integrated circuit reliability testing

    NASA Technical Reports Server (NTRS)

    Buehler, Martin G. (Inventor); Sayah, Hoshyar R. (Inventor)

    1988-01-01

    A technique is described for use in determining the reliability of microscopic conductors deposited on an uneven surface of an integrated circuit device. A wafer containing integrated circuit chips is formed with a test area having regions of different heights. At the time the conductors are formed on the chip areas of the wafer, an elongated serpentine assay conductor is deposited on the test area so the assay conductor extends over multiple steps between regions of different heights. Also, a first test conductor is deposited in the test area upon a uniform region of first height, and a second test conductor is deposited in the test area upon a uniform region of second height. The occurrence of high resistances at the steps between regions of different height is indicated by deriving the measured length of the serpentine conductor using the resistance measured between the ends of the serpentine conductor, and comparing that to the design length of the serpentine conductor. The percentage by which the measured length exceeds the design length, at which the integrated circuit will be discarded, depends on the required reliability of the integrated circuit.

  3. Wein bridge oscillator circuit

    NASA Technical Reports Server (NTRS)

    Lipoma, P. C.

    1971-01-01

    Circuit with minimum number of components provides stable outputs of 2 to 8 volts at frequencies of .001 to 100 kHz. Oscillator exhibits low power consumption, portability, simplicity, and drive capability, it has application as loudspeaker tester and audible alarm, as well as in laboratory and test generators.

  4. Resistor Combinations for Parallel Circuits.

    ERIC Educational Resources Information Center

    McTernan, James P.

    1978-01-01

    To help simplify both teaching and learning of parallel circuits, a high school electricity/electronics teacher presents and illustrates the use of tables of values for parallel resistive circuits in which total resistances are whole numbers. (MF)

  5. Electronic circuits and systems: A compilation. [including integrated circuits, logic circuits, varactor diode circuits, low pass filters, and optical equipment circuits

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Technological information is presented electronic circuits and systems which have potential utility outside the aerospace community. Topics discussed include circuit components such as filters, converters, and integrators, circuits designed for use with specific equipment or systems, and circuits designed primarily for use with optical equipment or displays.

  6. Methods of fabricating applique circuits

    DOEpatents

    Dimos, Duane B.; Garino, Terry J.

    1999-09-14

    Applique circuits suitable for advanced packaging applications are introduced. These structures are particularly suited for the simple integration of large amounts (many nanoFarads) of capacitance into conventional integrated circuit and multichip packaging technology. In operation, applique circuits are bonded to the integrated circuit or other appropriate structure at the point where the capacitance is required, thereby minimizing the effects of parasitic coupling. An immediate application is to problems of noise reduction and control in modern high-frequency circuitry.

  7. High voltage MOSFET switching circuit

    DOEpatents

    McEwan, T.E.

    1994-07-26

    The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET. 2 figs.

  8. Ladder-Type Circuits Revisited

    ERIC Educational Resources Information Center

    Yoon, Sung Hyun

    2007-01-01

    Ladder-type circuits where a given unit is repeated infinitely many times are dealt with in many textbooks on electromagnetism as examples of filter circuits. Determining the impedance of such circuits seems to be regarded as simple, which may be due to the fact that the invariance of the infinite system under the operation of adding one more unit…

  9. High voltage MOSFET switching circuit

    DOEpatents

    McEwan, Thomas E.

    1994-01-01

    The problem of source lead inductance in a MOSFET switching circuit is compensated for by adding an inductor to the gate circuit. The gate circuit inductor produces an inductive spike which counters the source lead inductive drop to produce a rectangular drive voltage waveform at the internal gate-source terminals of the MOSFET.

  10. Neuromorphic silicon neuron circuits.

    PubMed

    Indiveri, Giacomo; Linares-Barranco, Bernabé; Hamilton, Tara Julia; van Schaik, André; Etienne-Cummings, Ralph; Delbruck, Tobi; Liu, Shih-Chii; Dudek, Piotr; Häfliger, Philipp; Renaud, Sylvie; Schemmel, Johannes; Cauwenberghs, Gert; Arthur, John; Hynna, Kai; Folowosele, Fopefolu; Saighi, Sylvain; Serrano-Gotarredona, Teresa; Wijekoon, Jayawan; Wang, Yingxue; Boahen, Kwabena

    2011-01-01

    Hardware implementations of spiking neurons can be extremely useful for a large variety of applications, ranging from high-speed modeling of large-scale neural systems to real-time behaving systems, to bidirectional brain-machine interfaces. The specific circuit solutions used to implement silicon neurons depend on the application requirements. In this paper we describe the most common building blocks and techniques used to implement these circuits, and present an overview of a wide range of neuromorphic silicon neurons, which implement different computational models, ranging from biophysically realistic and conductance-based Hodgkin-Huxley models to bi-dimensional generalized adaptive integrate and fire models. We compare the different design methodologies used for each silicon neuron design described, and demonstrate their features with experimental results, measured from a wide range of fabricated VLSI chips. PMID:21747754

  11. PHASE DIFFERENTIAL INDICATING CIRCUIT

    DOEpatents

    Kirsten, F.A.

    1962-01-01

    An electronic circuit for totalizing the net phase difference between two alternating current signals is designed which responds to both increasing and decreasing phase changes. A phase comparator provldes an output pulse for each 360 deg of phase difference occurring, there being a negative pulse for phase shtft in one direction and a positive pulse for a phase shift in the opposite direction. A counting circuit utilizing glow discharge tubes receives the negative and positive pulses at a single input terminal and provides a running net total, pulses of one polarity dded and pulses of the opposite polarity being subtracted. The glow discharge tubes may be decaded to increase the total count capacity. (AEC)

  12. LC-circuit calorimetry

    SciTech Connect

    Bossen, O.; Schilling, A.

    2011-09-15

    We present a new type of calorimeter in which we couple an unknown heat capacity with the aid of Peltier elements to an electrical circuit. The use of an electrical inductance and an amplifier in the circuit allows us to achieve autonomous oscillations, and the measurement of the corresponding resonance frequency makes it possible to accurately measure the heat capacity with an intrinsic statistical uncertainty that decreases as {approx}t{sub m}{sup -3/2} with measuring time t{sub m}, as opposed to a corresponding uncertainty {approx}t{sub m}{sup -1/2} in the conventional alternating current method to measure heat capacities. We have built a demonstration experiment to show the feasibility of the new technique, and we have tested it on a gadolinium sample at its transition to the ferromagnetic state.

  13. GAS PHOTOTUBE CIRCUIT

    DOEpatents

    Richardson, J.H.

    1958-03-01

    This patent pertains to electronic circuits for measuring the intensity of light and is especially concerned with measurement between preset light thresholds. Such a circuit has application in connection with devices for reading-out information stored on punch cards or tapes where the cards and tapes are translucent. By the novel arrangement of this invention thc sensitivity of a gas phototube is maintained at a low value when the light intensity is below a first threshold level. If the light level rises above the first threshold level, the tube is rendered highly sensitive and an output signal will vary in proportion to the light intensity change. When the light level decreases below a second threshold level, the gas phototube is automatically rendered highly insensitive. Each of these threshold points is adjustable.

  14. Neuromorphic Silicon Neuron Circuits

    PubMed Central

    Indiveri, Giacomo; Linares-Barranco, Bernabé; Hamilton, Tara Julia; van Schaik, André; Etienne-Cummings, Ralph; Delbruck, Tobi; Liu, Shih-Chii; Dudek, Piotr; Häfliger, Philipp; Renaud, Sylvie; Schemmel, Johannes; Cauwenberghs, Gert; Arthur, John; Hynna, Kai; Folowosele, Fopefolu; Saighi, Sylvain; Serrano-Gotarredona, Teresa; Wijekoon, Jayawan; Wang, Yingxue; Boahen, Kwabena

    2011-01-01

    Hardware implementations of spiking neurons can be extremely useful for a large variety of applications, ranging from high-speed modeling of large-scale neural systems to real-time behaving systems, to bidirectional brain–machine interfaces. The specific circuit solutions used to implement silicon neurons depend on the application requirements. In this paper we describe the most common building blocks and techniques used to implement these circuits, and present an overview of a wide range of neuromorphic silicon neurons, which implement different computational models, ranging from biophysically realistic and conductance-based Hodgkin–Huxley models to bi-dimensional generalized adaptive integrate and fire models. We compare the different design methodologies used for each silicon neuron design described, and demonstrate their features with experimental results, measured from a wide range of fabricated VLSI chips. PMID:21747754

  15. Power supply conditioning circuit

    NASA Technical Reports Server (NTRS)

    Primas, L. E.; Loveland, R.

    1987-01-01

    A power supply conditioning circuit that can reduce Periodic and Random Deviations (PARD) on the output voltages of dc power supplies to -150 dBV from dc to several KHz with no measurable periodic deviations is described. The PARD for a typical commercial low noise power supply is -74 dBV for frequencies above 20 Hz and is often much worse at frequencies below 20 Hz. The power supply conditioning circuit described here relies on the large differences in the dynamic impedances of a constant current diode and a zener diode to establish a dc voltage with low PARD. Power supplies with low PARD are especially important in circuitry involving ultrastable frequencies for the Deep Space Network.

  16. Monolithic Optoelectronic Integrated Circuit

    NASA Technical Reports Server (NTRS)

    Bhasin, Kul B.; Walters, Wayne; Gustafsen, Jerry; Bendett, Mark

    1990-01-01

    Monolithic optoelectronic integrated circuit (OEIC) receives single digitally modulated input light signal via optical fiber and converts it into 16-channel electrical output signal. Potentially useful in any system in which digital data must be transmitted serially at high rates, then decoded into and used in parallel format at destination. Applications include transmission and decoding of control signals to phase shifters in phased-array antennas and also communication of data between computers and peripheral equipment in local-area networks.

  17. PARTICLE BEAM TRACKING CIRCUIT

    DOEpatents

    Anderson, O.A.

    1959-05-01

    >A particle-beam tracking and correcting circuit is described. Beam induction electrodes are placed on either side of the beam, and potentials induced by the beam are compared in a voltage comparator or discriminator. This comparison produces an error signal which modifies the fm curve at the voltage applied to the drift tube, thereby returning the orbit to the preferred position. The arrangement serves also to synchronize accelerating frequency and magnetic field growth. (T.R.H.)

  18. Integrated Circuit Immunity

    NASA Technical Reports Server (NTRS)

    Sketoe, J. G.; Clark, Anthony

    2000-01-01

    This paper presents a DOD E3 program overview on integrated circuit immunity. The topics include: 1) EMI Immunity Testing; 2) Threshold Definition; 3) Bias Tee Function; 4) Bias Tee Calibration Set-Up; 5) EDM Test Figure; 6) EMI Immunity Levels; 7) NAND vs. and Gate Immunity; 8) TTL vs. LS Immunity Levels; 9) TP vs. OC Immunity Levels; 10) 7805 Volt Reg Immunity; and 11) Seventies Chip Set. This paper is presented in viewgraph form.

  19. All Spin Digital Circuits

    NASA Astrophysics Data System (ADS)

    Behin-Aein, Behtash; Datta, Deepanjan; Salahuddin, Sayeef; Datta, Supriyo

    2009-03-01

    Switching of a magnetic free layer using spin polarized current has been demonstrated in Magnetic Tunnel Junction (MTJ) devices. Currently MTJ's are being studied for memory and microwave oscillator applications. The purpose of this talk is to explore a modified MTJ where a clock pulse via the fixed layer facilities the switching of the free layer in accordance with a weak bias provided by an input magnet in the form of a spin current. Based on the Landau-Lifshitz-Gilbert equation (LLG) augmented with spin torque functions, we show the switching energy and the switching time of the free layer which indicates the possibility of very low power digital logic applications. Ordinary digital circuits store information in the form of capacitor charges that communicate through electrical interconnects. The purpose of this paper is to show that modified MTJ's can be the basis for all spin digital circuits. Our primary objective is to stimulate proof of concept experiments that could usher in a whole new set of devices suitable for spintronic circuits.

  20. Optical Circuit Switched Protocol

    NASA Technical Reports Server (NTRS)

    Monacos, Steve P. (Inventor)

    2000-01-01

    The present invention is a system and method embodied in an optical circuit switched protocol for the transmission of data through a network. The optical circuit switched protocol is an all-optical circuit switched network and includes novel optical switching nodes for transmitting optical data packets within a network. Each optical switching node comprises a detector for receiving the header, header detection logic for translating the header into routing information and eliminating the header, and a controller for receiving the routing information and configuring an all optical path within the node. The all optical path located within the node is solely an optical path without having electronic storage of the data and without having optical delay of the data. Since electronic storage of the header is not necessary and the initial header is eliminated by the first detector of the first switching node. multiple identical headers are sent throughout the network so that subsequent switching nodes can receive and read the header for setting up an optical data path.

  1. Driven superconducting quantum circuits

    NASA Astrophysics Data System (ADS)

    Nakamura, Yasunobu

    2014-03-01

    Driven nonlinear quantum systems show rich phenomena in various fields of physics. Among them, superconducting quantum circuits have very attractive features such as well-controlled quantum states with design flexibility, strong nonlinearity of Josephson junctions, strong coupling to electromagnetic driving fields, little internal dissipation, and tailored coupling to the electromagnetic environment. We have investigated properties and functionalities of driven superconducting quantum circuits. A transmon qubit coupled to a transmission line shows nearly perfect spatial mode matching between the incident and scattered microwave field in the 1D mode. Dressed states under a driving field are studied there and also in a semi-infinite 1D mode terminated by a resonator containing a flux qubit. An effective Λ-type three-level system is realized under an appropriate driving condition. It allows ``impedance-matched'' perfect absorption of incident probe photons and down conversion into another frequency mode. Finally, the weak signal from the qubit is read out using a Josephson parametric amplifier/oscillator which is another nonlinear circuit driven by a strong pump field. This work was partly supported by the Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST), Project for Developing Innovation Systems of MEXT, MEXT KAKENHI ``Quantum Cybernetics,'' and the NICT Commissioned Research.

  2. Inkjet deposited circuit components

    NASA Astrophysics Data System (ADS)

    Bidoki, S. M.; Nouri, J.; Heidari, A. A.

    2010-05-01

    All-printed electronics as a means of achieving ultra-low-cost electronic circuits has attracted great interest in recent years. Inkjet printing is one of the most promising techniques by which the circuit components can be ultimately drawn (i.e. printed) onto the substrate in one step. Here, the inkjet printing technique was used to chemically deposit silver nanoparticles (10-200 nm) simply by ejection of silver nitrate and reducing solutions onto different substrates such as paper, PET plastic film and textile fabrics. The silver patterns were tested for their functionality to work as circuit components like conductor, resistor, capacitor and inductor. Different levels of conductivity were achieved simply by changing the printing sequence, inks ratio and concentration. The highest level of conductivity achieved by an office thermal inkjet printer (300 dpi) was 5.54 × 105 S m-1 on paper. Inkjet deposited capacitors could exhibit a capacitance of more than 1.5 nF (parallel plate 45 × 45 mm2) and induction coils displayed an inductance of around 400 µH (planar coil 10 cm in diameter). Comparison of electronic performance of inkjet deposited components to the performance of conventionally etched items makes the technique highly promising for fabricating different printed electronic devices.

  3. Fundamental Atomtronic Circuit Elements

    NASA Astrophysics Data System (ADS)

    Lee, Jeffrey; McIlvain, Brian; Lobb, Christopher; Hill, Wendell T., III

    2012-06-01

    Recent experiments with neutral superfluid gases have shown that it is possible to create atomtronic circuits analogous to existing superconducting circuits. The goals of these experiments are to create complex systems such as Josephson junctions. In addition, there are theoretical models for active atomtronic components analogous to diodes, transistors and oscillators. In order for any of these devices to function, an understanding of the more fundamental atomtronic elements is needed. Here we describe the first experimental realization of these more fundamental elements. We have created an atomtronic capacitor that is discharged through a resistance and inductance. We will discuss a theoretical description of the system that allows us to determine values for the capacitance, resistance and inductance. The resistance is shown to be analogous to the Sharvin resistance, and the inductance analogous to kinetic inductance in electronics. This atomtronic circuit is implemented with a thermal sample of laser cooled rubidium atoms. The atoms are confined using what we call free-space atom chips, a novel optical dipole trap produced using a generalized phase-contrast imaging technique. We will also discuss progress toward implementing this atomtronic system in a degenerate Bose gas.

  4. Coating Circuit Boards With Silicone

    NASA Technical Reports Server (NTRS)

    Gaudiano, S.

    1986-01-01

    Techniques appropriate to boards containing CMOS circuits detailed. Document presents procedure for applying thin conformal coating to such electronic assemblies as printed-circuit boards and wire-wrapped boards. Coating is from 1 to 7 mils (25 to 178 micrometers) thick and composed of room-temperature-vulcanizing (RTV) silicone. Specifies materials, equipment, spraying method, and quality requirements. Takes into account special needs of circuits made with complementary metal-oxide/semiconductor (CMOS) devices on circuit boards. Special attention given to preventing damage by electrostatic discharge, to which CMOS circuits especially sensitive.

  5. Power system with an integrated lubrication circuit

    SciTech Connect

    Hoff, Brian D.; Akasam, Sivaprasad; Algrain, Marcelo C.; Johnson, Kris W.; Lane, William H.

    2009-11-10

    A power system includes an engine having a first lubrication circuit and at least one auxiliary power unit having a second lubrication circuit. The first lubrication circuit is in fluid communication with the second lubrication circuit.

  6. Integrated coherent matter wave circuits

    NASA Astrophysics Data System (ADS)

    Ryu, C.; Boshier, M. G.

    2015-09-01

    An integrated coherent matter wave circuit is a single device, analogous to an integrated optical circuit, in which coherent de Broglie waves are created and then launched into waveguides where they can be switched, divided, recombined, and detected as they propagate. Applications of such circuits include guided atom interferometers, atomtronic circuits, and precisely controlled delivery of atoms. Here we report experiments demonstrating integrated circuits for guided coherent matter waves. The circuit elements are created with the painted potential technique, a form of time-averaged optical dipole potential in which a rapidly moving, tightly focused laser beam exerts forces on atoms through their electric polarizability. The source of coherent matter waves is a Bose-Einstein condensate (BEC). We launch BECs into painted waveguides that guide them around bends and form switches, phase coherent beamsplitters, and closed circuits. These are the basic elements that are needed to engineer arbitrarily complex matter wave circuitry.

  7. Memristor based startup circuit for self biased circuits

    NASA Astrophysics Data System (ADS)

    Das, Mangal; Singh, Amit Kumar; Rathi, Amit; Singhal, Sonal

    2016-04-01

    This paper presents the design of a Memristor based startup circuit for self biased circuits. Memristor has many advantages over conventional CMOS devices such as low leakage current at nanometer scale, easy to manufacture. In this work the switching characteristics of memristor is utilized. First the theoretical equations describing the switching behavior of memristor are investigated. To prove the switching capability of Memristor, a startup circuit based on memristor is proposed which uses series combination of Memristor and capacitor. Proposed circuit is compared with the previously reported MOSFET based startup circuits. Comparison of different circuits was done to validate the results. Simulation results show that memristor based circuit can attain on (I = 12.94 µA) to off state (I = 1 .2 µA) in 25 ns while the MOSFET based startup circuits take on (I = 14.19 µA) to off state (I = 1.4 µA) in more than 90 ns. The benefit comes in terms of area because the number of components used in the circuit are lesser than the conventional startup circuits.

  8. Electromechanical properties of MgZnO/ZnO heterostructures on flexible polyimide and stainless steel substrates under flexing

    NASA Astrophysics Data System (ADS)

    Wu, Tsung-Han; Chen, Jian-Zhang; Hsu, Cheng-Che; Cheng, I.-Chun

    2014-06-01

    We investigate the electromechanical properties of radio frequency (rf)-sputtered MgZnO/ZnO heterostructures on flexible polyimide (PI) and stainless steel 304 (StSt304) substrates. By subjecting ZnO to ultra-short (30-40 s) atmospheric pressure plasma jet treatment and prolonged (>3 h) thermal annealing at 300 °C, highly conductive interfaces are induced in rf-sputtered MgZnO/ZnO heterostructures on flexible PI and StSt304 substrates. The electrical properties of on-StSt MgZnO/ZnO annealed at 400 °C for 30 min are evaluated under the inward and outward bending conditions. Furthermore, the electrical properties of on-PI MgZnO/ZnO heterostructures annealed at 300 °C for 3 h are examined under the bending and stretching conditions. Compared with ZnO, MgZnO/ZnO heterostructures show better electrical stability under mechanical flexing; deviations in the electrical properties of MgZnO/ZnO heterostructures occur under larger strain levels. Piezoelectric polarization is induced under flexing, resulting in an increase or decrease in the resistance of MgZnO/ZnO heterostructures.

  9. Incidence of patellar clunk syndrome in fixed versus high-flex mobile bearing posterior-stabilized total knee arthroplasty.

    PubMed

    Snir, Nimrod; Schwarzkopf, Ran; Diskin, Brian; Takemoto, Richelle; Hamula, Mathew; Meere, Patrick A

    2014-10-01

    The geometry of the intercondylar box plays a significant role in the development of patellar clunk syndrome. We reviewed the incidence of patella clunk at mid-to-long-term follow-up of a rotating high-flex versus fixed bearing posterior stabilized TKA design. 188-mobile and 223-fixed bearing TKAs were reviewed for complications, incidence of patellar clunk, treatment, recurrence rates, range of motion, and patient satisfaction. Patellar clunk developed in 22 knees in the mobile (11.7%) and in 4 (1.8%) in the fixed bearing group (P<0.001). 23 out of 26 cases resolved with a single arthroscopic treatment and 2 resolved with a second procedure. The mean postoperative range of motion was 122.4°. All but one patient reported overall satisfaction with the index procedure. In contrast with other recent studies we found a significant incidence of patellar clunk in high-flex mobile bearings. Despite the high rate of patellar clunk syndrome, overall patients did well and were satisfied with their outcomes. PMID:24961894

  10. Dynamic pulse difference circuit

    DOEpatents

    Erickson, Gerald L.

    1978-01-01

    A digital electronic circuit of especial use for subtracting background activity pulses in gamma spectrometry comprises an up-down counter connected to count up with signal-channel pulses and to count down with background-channel pulses. A detector responsive to the count position of the up-down counter provides a signal when the up-down counter has completed one scaling sequence cycle of counts in the up direction. In an alternate embodiment, a detector responsive to the count position of the up-down counter provides a signal upon overflow of the counter.

  11. Base drive circuit

    DOEpatents

    Lange, A.C.

    1995-04-04

    An improved base drive circuit having a level shifter for providing bistable input signals to a pair of non-linear delays. The non-linear delays provide gate control to a corresponding pair of field effect transistors through a corresponding pair of buffer components. The non-linear delays provide delayed turn-on for each of the field effect transistors while an associated pair of transistors shunt the non-linear delays during turn-off of the associated field effect transistor. 2 figures.

  12. Biophotonic integrated circuits

    NASA Astrophysics Data System (ADS)

    Cohen, Daniel A.; Nolde, Jill A.; Wang, Chad S.; Skogen, Erik J.; Rivlin, A.; Coldren, Larry A.

    2004-12-01

    Biosensors rely on optical techniques to obtain high sensitivity and speed, but almost all biochips still require external light sources, optics, and detectors, which limits the widespread use of these devices. The optoelectronics technology base now allows monolithic integration of versatile optical sources, novel sensing geometries, filters, spectrometers, and detectors, enabling highly integrated chip-scale sensors. We discuss biophotonic integrated circuits built on both GaAs and InP substrates, incorporating widely tunable lasers, novel evanescent field sensing waveguides, heterodyne spectrometers, and waveguide photodetectors, suitable for high sensitivity transduction of affinity assays.

  13. Digital Optical Circuit Technology

    NASA Technical Reports Server (NTRS)

    Dove, B. L. (Editor)

    1985-01-01

    The Proceedings for the 48th Meeting of the AGARD Avionics Panel contain the 18 papers presented a Technical Evaluation Report, and discussions that followed the presentations of papers. Seven papers were presented in the session devoted to optical bistability. Optical logic was addressed by three papers. The session on sources, modulators and demodulators presented three papers. Five papers were given in the final session on all optical systems. The purpose of this Specialists' Meeting was to present the research and development status of digital optical circuit technology and to examine its relevance in the broad context of digital processing, communication, radar, avionics and flight control systems implementation.

  14. Photonic Integrated Circuits

    NASA Technical Reports Server (NTRS)

    Merritt, Scott; Krainak, Michael

    2016-01-01

    Integrated photonics generally is the integration of multiple lithographically defined photonic and electronic components and devices (e.g. lasers, detectors, waveguides passive structures, modulators, electronic control and optical interconnects) on a single platform with nanometer-scale feature sizes. The development of photonic integrated circuits permits size, weight, power and cost reductions for spacecraft microprocessors, optical communication, processor buses, advanced data processing, and integrated optic science instrument optical systems, subsystems and components. This is particularly critical for small spacecraft platforms. We will give an overview of some NASA applications for integrated photonics.

  15. Base drive circuit

    DOEpatents

    Lange, Arnold C.

    1995-01-01

    An improved base drive circuit (10) having a level shifter (24) for providing bistable input signals to a pair of non-linear delays (30, 32). The non-linear delays (30, 32) provide gate control to a corresponding pair of field effect transistors (100, 106) through a corresponding pair of buffer components (88, 94). The non-linear delays (30, 32) provide delayed turn-on for each of the field effect transistors (100, 106) while an associated pair of transistors (72, 80) shunt the non-linear delays (30, 32) during turn-off of the associated field effect transistor (100, 106).

  16. Seeing Circuits Assemble

    PubMed Central

    Lichtman, Jeff W.; Smith, Stephen J.

    2009-01-01

    Developmental neurobiology has been greatly invigorated by a recent string of breakthroughs in molecular biology and optical physics that permit direct in vivo observation of neural circuit assembly. The imaging done thus far suggests that as brains are built, a significant amount of unbuilding is also occurring. We offer the view that this tumult is the result of the intersecting behaviors of the many single-celled creatures (i.e., neurons, glia, and progenitors) that inhabit brains. New tools will certainly be needed if we wish to monitor the myriad cooperative and competitive interactions at play in the cellular society that builds brains. PMID:18995818

  17. Itch Mechanisms and Circuits

    PubMed Central

    Han, Liang; Dong, Xinzhong

    2014-01-01

    The itch-scratch reflex serves as a protective mechanism in everyday life. However, chronic persistent itching can be devastating. Despite the clinical importance of the itch sensation, its mechanism remains elusive. In the past decade, substantial progress has been made to uncover the mystery of itching. Here, we review the molecules, cells, and circuits known to mediate the itch sensation, which, coupled with advances in understanding the pathophysiology of chronic itching conditions, will hopefully contribute to the development of new anti-itch therapies. PMID:24819620

  18. Integrated circuit cell library

    NASA Technical Reports Server (NTRS)

    Whitaker, Sterling R. (Inventor); Miles, Lowell H. (Inventor)

    2005-01-01

    According to the invention, an ASIC cell library for use in creation of custom integrated circuits is disclosed. The ASIC cell library includes some first cells and some second cells. Each of the second cells includes two or more kernel cells. The ASIC cell library is at least 5% comprised of second cells. In various embodiments, the ASIC cell library could be 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more comprised of second cells.

  19. Optically controllable molecular logic circuits

    NASA Astrophysics Data System (ADS)

    Nishimura, Takahiro; Fujii, Ryo; Ogura, Yusuke; Tanida, Jun

    2015-07-01

    Molecular logic circuits represent a promising technology for observation and manipulation of biological systems at the molecular level. However, the implementation of molecular logic circuits for temporal and programmable operation remains challenging. In this paper, we demonstrate an optically controllable logic circuit that uses fluorescence resonance energy transfer (FRET) for signaling. The FRET-based signaling process is modulated by both molecular and optical inputs. Based on the distance dependence of FRET, the FRET pathways required to execute molecular logic operations are formed on a DNA nanostructure as a circuit based on its molecular inputs. In addition, the FRET pathways on the DNA nanostructure are controlled optically, using photoswitching fluorescent molecules to instruct the execution of the desired operation and the related timings. The behavior of the circuit can thus be controlled using external optical signals. As an example, a molecular logic circuit capable of executing two different logic operations was studied. The circuit contains functional DNAs and a DNA scaffold to construct two FRET routes for executing Input 1 AND Input 2 and Input 1 AND NOT Input 3 operations on molecular inputs. The circuit produced the correct outputs with all possible combinations of the inputs by following the light signals. Moreover, the operation execution timings were controlled based on light irradiation and the circuit responded to time-dependent inputs. The experimental results demonstrate that the circuit changes the output for the required operations following the input of temporal light signals.

  20. Optically controllable molecular logic circuits

    SciTech Connect

    Nishimura, Takahiro Fujii, Ryo; Ogura, Yusuke; Tanida, Jun

    2015-07-06

    Molecular logic circuits represent a promising technology for observation and manipulation of biological systems at the molecular level. However, the implementation of molecular logic circuits for temporal and programmable operation remains challenging. In this paper, we demonstrate an optically controllable logic circuit that uses fluorescence resonance energy transfer (FRET) for signaling. The FRET-based signaling process is modulated by both molecular and optical inputs. Based on the distance dependence of FRET, the FRET pathways required to execute molecular logic operations are formed on a DNA nanostructure as a circuit based on its molecular inputs. In addition, the FRET pathways on the DNA nanostructure are controlled optically, using photoswitching fluorescent molecules to instruct the execution of the desired operation and the related timings. The behavior of the circuit can thus be controlled using external optical signals. As an example, a molecular logic circuit capable of executing two different logic operations was studied. The circuit contains functional DNAs and a DNA scaffold to construct two FRET routes for executing Input 1 AND Input 2 and Input 1 AND NOT Input 3 operations on molecular inputs. The circuit produced the correct outputs with all possible combinations of the inputs by following the light signals. Moreover, the operation execution timings were controlled based on light irradiation and the circuit responded to time-dependent inputs. The experimental results demonstrate that the circuit changes the output for the required operations following the input of temporal light signals.

  1. FLORIS: phase A status of the fluorescence imaging spectrometer of the Earth Explorer mission candidate FLEX

    NASA Astrophysics Data System (ADS)

    Kraft, S.; Bézy, J.-L.; Del Bello, U.; Berlich, R.; Drusch, M.; Franco, R.; Gabriele, A.; Harnisch, B.; Meynart, R.; Silvestrin, P.

    2013-10-01

    The Fluorescence Explorer (FLEX) mission is currently subject to feasibility (Phase A) study as one of the two candidates of ESA's 8th Earth Explorer opportunity mission. The FLuORescence Imaging Spectrometer (FLORIS) will be an imaging grating spectrometer onboard of a medium sized satellite flying in tandem with Sentinel-3 in a Sun synchronous orbit at a height of about 815 km. FLORIS will observe vegetation fluorescence and reflectance within a spectral range between 500 nm and 780 nm. It will thereby cover the photochemical reflection features between 500 nm and 600 nm, the Chlorophyll absorption band between 600 and 677 nm, and the red-edge in the region from 697 nm to 755 nm being located between the Oxygen A and B absorption bands. By this measurement approach, it is expected that the full spectrum and amount of the vegetation fluorescence radiance can be retrieved, and that atmospheric corrections can efficiently be applied. FLORIS will measure Earth reflected spectral radiance at a relatively high spectral resolution of ~0.3 nm around the Oxygen absorption bands. Other spectral band areas with less pronounced absorption features will be measured at medium spectral resolution between 0.5 and 2 nm. FLORIS will provide imagery at 300 m resolution on ground with a swath width of 150 km. This will allow achieving global revisit times of less than one month so as to monitor seasonal variations of the vegetation cycles. The mission life time is expected to be at least 4 years. The fluorescence retrieval will make use of information coming from OLCI and SLSTR, which are onboard of Sentinel-3, to monitor temperature, to detect thin clouds and to derive vegetation reflectance and information on the aerosol content also outside the FLORIS spectral range. In order to mitigate the technological and programmatic risk of this Explorer mission candidate, ESA has initiated two comprehensive bread-boarding activities, in which the most critical technologies and instrument

  2. Vegetation stress from soil moisture and chlorophyll fluorescence: synergy between SMAP and FLEX approaches

    NASA Astrophysics Data System (ADS)

    Moreno, Jose; Moran, Susan

    2014-05-01

    Vegetation stress detection continues being a focal objective for remote sensing techniques. It has implications not only for practical applications such as irrigation optimization or precision agriculture, but also for global climate models, providing data to better link water and carbon exchanges between the surface and the atmospheric and improved parameterization of the role of terrestrial vegetation in the coupling of water and carbon cycles. Traditional approaches to map vegetation stress using remote sensing techniques have been based on measurements of soil moisture status, canopy (radiometric) temperature and, to a lesser extent, canopy water content, but new techniques such as the dynamics of vegetation fluorescence emission, are also now available. Within the context of the preparatory activities for the SMAP and FLEX missions, a number of initiatives have been put in place to combine modelling activities and field experiments in order to look for alternative and more efficient ways of detecting vegetation stress, with emphasis on synergistic remote sensing approaches. The potential of solar-induced vegetation fluorescence as an early indicator of stress has been widely demonstrated, for different type of stress conditions: light amount (excess illumination) and conditions (direct/diffuse), temperature extremes (low and high), soil water availability (soil moisture), soil nutrients (nitrogen), atmospheric water vapour and atmospheric CO2 concentration. The effects caused by different stress conditions are sometimes difficult to be decoupled, also because different causes are often combined, but in general they then to change the overall fluorescence emission (modulating amplitude) or changing the relative contributions of photosystems PSI and PSII or the relative fluorescence re-absorption effects caused by modifications in the structure of pigment bed responsible for light absorption, in particular for acclimation for persistent stress conditions. While

  3. Sequential circuit design for radiation hardened multiple voltage integrated circuits

    DOEpatents

    Clark, Lawrence T.; McIver, III, John K.

    2009-11-24

    The present invention includes a radiation hardened sequential circuit, such as a bistable circuit, flip-flop or other suitable design that presents substantial immunity to ionizing radiation while simultaneously maintaining a low operating voltage. In one embodiment, the circuit includes a plurality of logic elements that operate on relatively low voltage, and a master and slave latches each having storage elements that operate on a relatively high voltage.

  4. Time in Cortical Circuits

    PubMed Central

    Shadlen, Michael N.; Jazayeri, Mehrdad; Nobre, Anna C.; Buonomano, Dean V.

    2015-01-01

    Time is central to cognition. However, the neural basis for time-dependent cognition remains poorly understood. We explore how the temporal features of neural activity in cortical circuits and their capacity for plasticity can contribute to time-dependent cognition over short time scales. This neural activity is linked to cognition that operates in the present or anticipates events or stimuli in the near future. We focus on deliberation and planning in the context of decision making as a cognitive process that integrates information across time. We progress to consider how temporal expectations of the future modulate perception. We propose that understanding the neural basis for how the brain tells time and operates in time will be necessary to develop general models of cognition. SIGNIFICANCE STATEMENT Time is central to cognition. However, the neural basis for time-dependent cognition remains poorly understood. We explore how the temporal features of neural activity in cortical circuits and their capacity for plasticity can contribute to time-dependent cognition over short time scales. We propose that understanding the neural basis for how the brain tells time and operates in time will be necessary to develop general models of cognition. PMID:26468192

  5. Noise in biological circuits

    SciTech Connect

    Simpson, Michael L; Allen, Michael S.; Cox, Chris D.; Dar, Roy D.; Karig, David K; McCollum, James M.; Cooke, John F

    2009-01-01

    Noise biology focuses on the sources, processing, and biological consequences of the inherent stochastic fluctuations in molecular transitions or interactions that control cellular behavior. These fluctuations are especially pronounced in small systems where the magnitudes of the fluctuations approach or exceed the mean value of the molecular population. Noise biology is an essential component of nanomedicine where the communication of information is across a boundary that separates small synthetic and biological systems that are bound by their size to reside in environments of large fluctuations. Here we review the fundamentals of the computational, analytical, and experimental approaches to noise biology. We review results that show that the competition between the benefits of low noise and those of low population has resulted in the evolution of genetic system architectures that produce an uneven distribution of stochasticity across the molecular components of cells and, in some cases, use noise to drive biological function. We review the exact and approximate approaches to gene circuit noise analysis and simulation, and reviewmany of the key experimental results obtained using flow cytometry and time-lapse fluorescent microscopy. In addition, we consider the probative value of noise with a discussion of using measured noise properties to elucidate the structure and function of the underlying gene circuit. We conclude with a discussion of the frontiers of and significant future challenges for noise biology.

  6. Quasi-Linear Circuit

    NASA Technical Reports Server (NTRS)

    Bradley, William; Bird, Ross; Eldred, Dennis; Zook, Jon; Knowles, Gareth

    2013-01-01

    This work involved developing spacequalifiable switch mode DC/DC power supplies that improve performance with fewer components, and result in elimination of digital components and reduction in magnetics. This design is for missions where systems may be operating under extreme conditions, especially at elevated temperature levels from 200 to 300 degC. Prior art for radiation-tolerant DC/DC converters has been accomplished utilizing classical magnetic-based switch mode converter topologies; however, this requires specific shielding and component de-rating to meet the high-reliability specifications. It requires complex measurement and feedback components, and will not enable automatic re-optimization for larger changes in voltage supply or electrical loading condition. The innovation is a switch mode DC/DC power supply that eliminates the need for processors and most magnetics. It can provide a well-regulated voltage supply with a gain of 1:100 step-up to 8:1 step down, tolerating an up to 30% fluctuation of the voltage supply parameters. The circuit incorporates a ceramic core transformer in a manner that enables it to provide a well-regulated voltage output without use of any processor components or magnetic transformers. The circuit adjusts its internal parameters to re-optimize its performance for changes in supply voltage, environmental conditions, or electrical loading at the output

  7. Jitter compensation circuit

    DOEpatents

    Sullivan, J.S.; Ball, D.G.

    1997-09-09

    The instantaneous V{sub co} signal on a charging capacitor is sampled and the charge voltage on capacitor C{sub o} is captured just prior to its discharge into the first stage of magnetic modulator. The captured signal is applied to an averaging circuit with a long time constant and to the positive input terminal of a differential amplifier. The averaged V{sub co} signal is split between a gain stage (G = 0.975) and a feedback stage that determines the slope of the voltage ramp applied to the high speed comparator. The 97.5% portion of the averaged V{sub co} signal is applied to the negative input of a differential amplifier gain stage (G = 10). The differential amplifier produces an error signal by subtracting 97.5% of the averaged V{sub co} signal from the instantaneous value of sampled V{sub co} signal and multiplying the difference by ten. The resulting error signal is applied to the positive input of a high speed comparator. The error signal is then compared to a voltage ramp that is proportional to the averaged V{sub co} values squared divided by the total volt-second product of the magnetic compression circuit. 11 figs.

  8. Jitter compensation circuit

    DOEpatents

    Sullivan, James S.; Ball, Don G.

    1997-01-01

    The instantaneous V.sub.co signal on a charging capacitor is sampled and the charge voltage on capacitor C.sub.o is captured just prior to its discharge into the first stage of magnetic modulator. The captured signal is applied to an averaging circuit with a long time constant and to the positive input terminal of a differential amplifier. The averaged V.sub. co signal is split between a gain stage (G=0.975) and a feedback stage that determines the slope of the voltage ramp applied to the high speed comparator. The 97.5% portion of the averaged V.sub.co signal is applied to the negative input of a differential amplifier gain stage (G=10). The differential amplifier produces an error signal by subtracting 97.5% of the averaged V.sub.co signal from the instantaneous value of sampled V.sub.co signal and multiplying the difference by ten. The resulting error signal is applied to the positive input of a high speed comparator. The error signal is then compared to a voltage ramp that is proportional to the averaged V.sub.co values squared divided by the total volt-second product of the magnetic compression circuit.

  9. Simple Cell Balance Circuit

    NASA Technical Reports Server (NTRS)

    Johnson, Steven D.; Byers, Jerry W.; Martin, James A.

    2012-01-01

    A method has been developed for continuous cell voltage balancing for rechargeable batteries (e.g. lithium ion batteries). A resistor divider chain is provided that generates a set of voltages representing the ideal cell voltage (the voltage of each cell should be as if the cells were perfectly balanced). An operational amplifier circuit with an added current buffer stage generates the ideal voltage with a very high degree of accuracy, using the concept of negative feedback. The ideal voltages are each connected to the corresponding cell through a current- limiting resistance. Over time, having the cell connected to the ideal voltage provides a balancing current that moves the cell voltage very close to that ideal level. In effect, it adjusts the current of each cell during charging, discharging, and standby periods to force the cell voltages to be equal to the ideal voltages generated by the resistor divider. The device also includes solid-state switches that disconnect the circuit from the battery so that it will not discharge the battery during storage. This solution requires relatively few parts and is, therefore, of lower cost and of increased reliability due to the fewer failure modes. Additionally, this design uses very little power. A preliminary model predicts a power usage of 0.18 W for an 8-cell battery. This approach is applicable to a wide range of battery capacities and voltages.

  10. A bit serial sequential circuit

    NASA Technical Reports Server (NTRS)

    Hu, S.; Whitaker, S.

    1990-01-01

    Normally a sequential circuit with n state variables consists of n unique hardware realizations, one for each state variable. All variables are processed in parallel. This paper introduces a new sequential circuit architecture that allows the state variables to be realized in a serial manner using only one next state logic circuit. The action of processing the state variables in a serial manner has never been addressed before. This paper presents a general design procedure for circuit construction and initialization. Utilizing pass transistors to form the combinational next state forming logic in synchronous sequential machines, a bit serial state machine can be realized with a single NMOS pass transistor network connected to shift registers. The bit serial state machine occupies less area than other realizations which perform parallel operations. Moreover, the logical circuit of the bit serial state machine can be modified by simply changing the circuit input matrix to develop an adaptive state machine.

  11. Automated Design of Quantum Circuits

    NASA Technical Reports Server (NTRS)

    Williams, Colin P.; Gray, Alexander G.

    2000-01-01

    In order to design a quantum circuit that performs a desired quantum computation, it is necessary to find a decomposition of the unitary matrix that represents that computation in terms of a sequence of quantum gate operations. To date, such designs have either been found by hand or by exhaustive enumeration of all possible circuit topologies. In this paper we propose an automated approach to quantum circuit design using search heuristics based on principles abstracted from evolutionary genetics, i.e. using a genetic programming algorithm adapted specially for this problem. We demonstrate the method on the task of discovering quantum circuit designs for quantum teleportation. We show that to find a given known circuit design (one which was hand-crafted by a human), the method considers roughly an order of magnitude fewer designs than naive enumeration. In addition, the method finds novel circuit designs superior to those previously known.

  12. Source-circuit design overview

    NASA Technical Reports Server (NTRS)

    Ross, R. G., Jr.

    1983-01-01

    The source circuit is the fundamental electrical building block of a large central-station array; it consists of a series-parallel network of solar cells that develops full system voltage. The array field is generally made up of a large number of parallel source circuits. Source-circuit electrical configuration is driven by a number of design considerations, which must be considered simultaneously. Array fault tolerance and hot spot heating endurance are examined in detail.

  13. Audio distribution and Monitoring Circuit

    NASA Technical Reports Server (NTRS)

    Kirkland, J. M.

    1983-01-01

    Versatile circuit accepts and distributes TV audio signals. Three-meter audio distribution and monitoring circuit provides flexibility in monitoring, mixing, and distributing audio inputs and outputs at various signal and impedance levels. Program material is simultaneously monitored on three channels, or single-channel version built to monitor transmitted or received signal levels, drive speakers, interface to building communications, and drive long-line circuits.

  14. Power-Supply-Conditioning Circuit

    NASA Technical Reports Server (NTRS)

    Primas, L. E.; Loveland, R. C.

    1989-01-01

    Fluctuations of voltage suppressed in power supplies for precise radio-frequency circuits. Circuit suppresses both periodic and random deviations of dc supply voltage from desired steady level. Highly-stable feedback voltage regulator, conditioner intended in conjunction with conventional power-supply circuit to provide constant voltage to atomic frequency standard or other precise oscillator. Without conditioners, outputs of most commercial power supplies contain fluctuations causing unacceptably-large phase and amplitude modulation of precise oscillators.

  15. Electronic control circuits: A compilation

    NASA Technical Reports Server (NTRS)

    1973-01-01

    A compilation of technical R and D information on circuits and modular subassemblies is presented as a part of a technology utilization program. Fundamental design principles and applications are given. Electronic control circuits discussed include: anti-noise circuit; ground protection device for bioinstrumentation; temperature compensation for operational amplifiers; hybrid gatling capacitor; automatic signal range control; integrated clock-switching control; and precision voltage tolerance detector.

  16. Four-junction superconducting circuit.

    PubMed

    Qiu, Yueyin; Xiong, Wei; He, Xiao-Ling; Li, Tie-Fu; You, J Q

    2016-01-01

    We develop a theory for the quantum circuit consisting of a superconducting loop interrupted by four Josephson junctions and pierced by a magnetic flux (either static or time-dependent). In addition to the similarity with the typical three-junction flux qubit in the double-well regime, we demonstrate the difference of the four-junction circuit from its three-junction analogue, including its advantages over the latter. Moreover, the four-junction circuit in the single-well regime is also investigated. Our theory provides a tool to explore the physical properties of this four-junction superconducting circuit. PMID:27356619

  17. PRECISION TIME-DELAY CIRCUIT

    DOEpatents

    Creveling, R.

    1959-03-17

    A tine-delay circuit which produces a delay time in d. The circuit a capacitor, an te back resistance, connected serially with the anode of the diode going to ground. At the start of the time delay a negative stepfunction is applied to the series circuit and initiates a half-cycle transient oscillatory voltage terminated by a transient oscillatory voltage of substantially higher frequency. The output of the delay circuit is taken at the junction of the inductor and diode where a sudden voltage rise appears after the initiation of the higher frequency transient oscillations.

  18. Four-junction superconducting circuit

    NASA Astrophysics Data System (ADS)

    Qiu, Yueyin; Xiong, Wei; He, Xiao-Ling; Li, Tie-Fu; You, J. Q.

    2016-06-01

    We develop a theory for the quantum circuit consisting of a superconducting loop interrupted by four Josephson junctions and pierced by a magnetic flux (either static or time-dependent). In addition to the similarity with the typical three-junction flux qubit in the double-well regime, we demonstrate the difference of the four-junction circuit from its three-junction analogue, including its advantages over the latter. Moreover, the four-junction circuit in the single-well regime is also investigated. Our theory provides a tool to explore the physical properties of this four-junction superconducting circuit.

  19. Magnetic compression laser driving circuit

    DOEpatents

    Ball, D.G.; Birx, D.; Cook, E.G.

    1993-01-05

    A magnetic compression laser driving circuit is disclosed. The magnetic compression laser driving circuit compresses voltage pulses in the range of 1.5 microseconds at 20 kilovolts of amplitude to pulses in the range of 40 nanoseconds and 60 kilovolts of amplitude. The magnetic compression laser driving circuit includes a multi-stage magnetic switch where the last stage includes a switch having at least two turns which has larger saturated inductance with less core material so that the efficiency of the circuit and hence the laser is increased.

  20. Magnetic compression laser driving circuit

    DOEpatents

    Ball, Don G.; Birx, Dan; Cook, Edward G.

    1993-01-01

    A magnetic compression laser driving circuit is disclosed. The magnetic compression laser driving circuit compresses voltage pulses in the range of 1.5 microseconds at 20 Kilovolts of amplitude to pulses in the range of 40 nanoseconds and 60 Kilovolts of amplitude. The magnetic compression laser driving circuit includes a multi-stage magnetic switch where the last stage includes a switch having at least two turns which has larger saturated inductance with less core material so that the efficiency of the circuit and hence the laser is increased.

  1. Four-junction superconducting circuit

    PubMed Central

    Qiu, Yueyin; Xiong, Wei; He, Xiao-Ling; Li, Tie-Fu; You, J. Q.

    2016-01-01

    We develop a theory for the quantum circuit consisting of a superconducting loop interrupted by four Josephson junctions and pierced by a magnetic flux (either static or time-dependent). In addition to the similarity with the typical three-junction flux qubit in the double-well regime, we demonstrate the difference of the four-junction circuit from its three-junction analogue, including its advantages over the latter. Moreover, the four-junction circuit in the single-well regime is also investigated. Our theory provides a tool to explore the physical properties of this four-junction superconducting circuit. PMID:27356619

  2. Primary emissions and secondary organic aerosol formation from the exhaust of a flex-fuel (ethanol) vehicle

    NASA Astrophysics Data System (ADS)

    Suarez-Bertoa, R.; Zardini, A. A.; Platt, S. M.; Hellebust, S.; Pieber, S. M.; El Haddad, I.; Temime-Roussel, B.; Baltensperger, U.; Marchand, N.; Prévôt, A. S. H.; Astorga, C.

    2015-09-01

    Incentives to use biofuels may result in increasing vehicular emissions of compounds detrimental to air quality. Therefore, regulated and unregulated emissions from a Euro 5a flex-fuel vehicle, tested using E85 and E75 blends (gasoline containing 85% and 75% of ethanol (vol/vol), respectively), were investigated at 22 and -7 °C over the New European Driving Cycle, at the Vehicle Emission Laboratory at the European Commission Joint Research Centre Ispra, Italy. Vehicle exhaust was comprehensively analyzed at the tailpipe and in a dilution tunnel. A fraction of the exhaust was injected into a mobile smog chamber to study the photochemical aging of the mixture. We found that emissions from a flex-fuel vehicle, fueled by E85 and E75, led to secondary organic aerosol (SOA) formation, despite the low aromatic content of these fuel blends. Emissions of regulated and unregulated compounds, as well as emissions of black carbon (BC) and primary organic aerosol (POA) and SOA formation were higher at -7 °C. The flex-fuel unregulated emissions, mainly composed of ethanol and acetaldehyde, resulted in very high ozone formation potential and SOA, especially at low temperature (860 mg O3 km-1 and up to 38 mg C kg-1). After an OH exposure of 10 × 106 cm-3 h, SOA mass was, on average, 3 times larger than total primary particle mass emissions (BC + POA) with a high O:C ratio (up to 0.7 and 0.5 at 22 and -7 °C, respectively) typical of highly oxidized mixtures. Furthermore, high resolution organic mass spectra showed high 44/43 ratios (ratio of the ions m/z 44 and m/z 43) characteristic of low-volatility oxygenated organic aerosol. We also hypothesize that SOA formation from vehicular emissions could be due to oxidation products of ethanol and acetaldehyde, both short-chain oxygenated VOCs, e.g. methylglyoxal and acetic acid, and not only from aromatic compounds.

  3. A Circuit to Demonstrate Phase Relationships in "RLC" Circuits

    ERIC Educational Resources Information Center

    Sokol, P. E.; Warren, G.; Zheng, B.; Smith, P.

    2013-01-01

    We have developed a circuit to demonstrate the phase relationships between resistive and reactive elements in series "RLC" circuits. We utilize a differential amplifier to allow the phases of the three elements and the current to be simultaneously displayed on an inexpensive four channel oscilloscope. We have included a novel circuit…

  4. ELECTRONIC PULSE SCALING CIRCUITS

    DOEpatents

    Cooke-Yarborough, E.H.

    1958-11-18

    Electronic pulse scaling circults of the klnd comprlsing a serles of bi- stable elements connected ln sequence, usually in the form of a rlng so as to be cycllcally repetitive at the highest scallng factor, are described. The scaling circuit comprises a ring system of bi-stable elements each arranged on turn-off to cause, a succeeding element of the ring to be turned-on, and one being arranged on turn-off to cause a further element of the ring to be turned-on. In addition, separate means are provided for applying a turn-off pulse to all the elements simultaneously, and for resetting the elements to a starting condition at the end of each cycle.

  5. Laser diode protection circuit

    SciTech Connect

    Burgyan, L.; Hand, W.L.

    1990-05-08

    This patent describes a method for protecting a laser diode included within an electro-optical circuit. It comprises: the laser diode, a DC bias supply for supplying forward conduction current to the laser diode to cause it to emit light energy at a predetermined quiescent operating point, and an RF amplifier means for supplying an RF amplitude of an analog modulating signal to the laser diode for modulating the intensity of the emitted light energy about the quiescent operating point thereof, the method including providing a very high impedance to the laser diode during its nominal operating conditions about the quiescent point and, sensing an instantaneous amplitude of the RF amplitude modulating signal to detect amplitude surges therein, and responding to the sensing means by removing forward conduction current from the laser diode during the sense amplitude surges int he RF amplitude of the analog modulating signal, thereby causing the laser diode to reduce emission of light energy to a safe level.

  6. Modeling cortical circuits.

    SciTech Connect

    Rohrer, Brandon Robinson; Rothganger, Fredrick H.; Verzi, Stephen J.; Xavier, Patrick Gordon

    2010-09-01

    The neocortex is perhaps the highest region of the human brain, where audio and visual perception takes place along with many important cognitive functions. An important research goal is to describe the mechanisms implemented by the neocortex. There is an apparent regularity in the structure of the neocortex [Brodmann 1909, Mountcastle 1957] which may help simplify this task. The work reported here addresses the problem of how to describe the putative repeated units ('cortical circuits') in a manner that is easily understood and manipulated, with the long-term goal of developing a mathematical and algorithmic description of their function. The approach is to reduce each algorithm to an enhanced perceptron-like structure and describe its computation using difference equations. We organize this algorithmic processing into larger structures based on physiological observations, and implement key modeling concepts in software which runs on parallel computing hardware.

  7. ELECTRONIC INTEGRATING CIRCUIT

    DOEpatents

    Englemann, R.H.

    1963-08-20

    An electronic integrating circuit using a transistor with a capacitor connected between the emitter and collector through which the capacitor discharges at a rate proportional to the input current at the base is described. Means are provided for biasing the base with an operating bias and for applying a voltage pulse to the capacitor for charging to an initial voltage. A current dividing diode is connected between the base and emitter of the transistor, and signal input terminal means are coupled to the juncture of the capacitor and emitter and to the base of the transistor. At the end of the integration period, the residual voltage on said capacitor is less by an amount proportional to the integral of the input signal. Either continuous or intermittent periods of integration are provided. (AEC)

  8. Photoconductive circuit element reflectometer

    DOEpatents

    Rauscher, C.

    1987-12-07

    A photoconductive reflectometer for characterizing semiconductor devices at millimeter wavelength frequencies where a first photoconductive circuit element (PCE) is biased by a direct current voltage source and produces short electrical pulses when excited into conductance by short first laser light pulses. The electrical pulses are electronically conditioned to improve the frequency related amplitude characteristics of the pulses which thereafter propagate along a transmission line to a device under test. Second PCEs are connected along the transmission line to sample the signals on the transmission line when excited into conductance by short second laser light pulses, spaced apart in time a determinable period from the first laser light pulses. Electronic filters connected to each of the second PCEs act as low-pass filters and remove parasitic interference from the sampled signals and output the sampled signals in the form of slowed-motion images of the signals on the transmission line. 4 figs.

  9. Photoconductive circuit element reflectometer

    DOEpatents

    Rauscher, Christen

    1990-01-01

    A photoconductive reflectometer for characterizing semiconductor devices at millimeter wavelength frequencies where a first photoconductive circuit element (PCE) is biased by a direct current voltage source and produces short electrical pulses when excited into conductance by short first laser light pulses. The electrical pulses are electronically conditioned to improve the frequency related amplitude characteristics of the pulses which thereafter propagate along a transmission line to a device under test. Second PCEs are connected along the transmission line to sample the signals on the transmission line when excited into conductance by short second laser light pulses, spaced apart in time a variable period from the first laser light pulses. Electronic filters connected to each of the second PCEs act as low-pass filters and remove parasitic interference from the sampled signals and output the sampled signals in the form of slowed-motion images of the signals on the transmission line.

  10. VLSI circuits implementing computational models of neocortical circuits.

    PubMed

    Wijekoon, Jayawan H B; Dudek, Piotr

    2012-09-15

    This paper overviews the design and implementation of three neuromorphic integrated circuits developed for the COLAMN ("Novel Computing Architecture for Cognitive Systems based on the Laminar Microcircuitry of the Neocortex") project. The circuits are implemented in a standard 0.35 μm CMOS technology and include spiking and bursting neuron models, and synapses with short-term (facilitating/depressing) and long-term (STDP and dopamine-modulated STDP) dynamics. They enable execution of complex nonlinear models in accelerated-time, as compared with biology, and with low power consumption. The neural dynamics are implemented using analogue circuit techniques, with digital asynchronous event-based input and output. The circuits provide configurable hardware blocks that can be used to simulate a variety of neural networks. The paper presents experimental results obtained from the fabricated devices, and discusses the advantages and disadvantages of the analogue circuit approach to computational neural modelling. PMID:22342970

  11. The Influence of Age at Single-Event Multilevel Surgery on Outcome in Children with Cerebral Palsy Who Walk with Flexed Knee Gait

    ERIC Educational Resources Information Center

    Svehlik, Martin; Steinwender, Gerhard; Kraus, Tanja; Saraph, Vinay; Lehmann, Thomas; Linhart, Wolfgang E.; Zwick, Ernst B.

    2011-01-01

    Aim: Information on the timing and long-term outcome of single-event multilevel surgery in children with bilateral spastic cerebral palsy (CP) walking with flexed knee gait is limited. Based on our clinical experience, we hypothesized that older children with bilateral spastic CP would benefit more from single-event multilevel surgery than younger…

  12. From Local to EXtreme Environments (FLEXE) Student-Scientist Online Forums: hypothesis-based research examining ways to involve scientists in effective science education

    NASA Astrophysics Data System (ADS)

    Goehring, L.; Carlsen, W.; Fisher, C. R.; Kerlin, S.; Trautmann, N.; Petersen, W.

    2011-12-01

    Science education reform since the mid-1990's has called for a "new way of teaching and learning about science that reflects how science itself is done, emphasizing inquiry as a way of achieving knowledge and understanding about the world" (NRC, 1996). Scientists and engineers, experts in inquiry thinking, have been called to help model these practices for students and demonstrate scientific habits of mind. The question, however, is "how best to involve these experts?" given the very real challenges of limited availability of scientists, varying experience with effective pedagogy, widespread geographic distribution of schools, and the sheer number of students involved. Technology offers partial solutions to enable Student-Scientist Interactions (SSI). The FLEXE Project has developed online FLEXE Forums to support efficient, effective SSIs, making use of web-based and database technology to facilitate communication between students and scientists. More importantly, the FLEXE project has approached this question of "how best to do this?" scientifically, combining program evaluation with hypothesis-based research explicitly testing the effects of such SSIs on student learning and attitudes towards science. FLEXE Forums are designed to showcase scientific practices and habits of mind through facilitated interaction between students and scientists. Through these Forums, students "meet" working scientists and learn about their research and the environments in which they work. Scientists provide students with intriguing "real-life" datasets and challenge students to analyze and interpret the data through guiding questions. Students submit their analyses to the Forum, and scientists provide feedback and connect the instructional activity with real-life practice, showcasing their activities in the field. In the FLEXE project, Forums are embedded within inquiry-based instructional units focused on essential learning concepts, and feature the deep-sea environment in contrast

  13. Physical Activity, Function, and Quality of Life: Design and Methods of the FlexToBa™ Trial

    PubMed Central

    McAuley, Edward; Wójcicki, Thomas R.; White, Siobhan M.; Mailey, Emily L.; Szabo, Amanda N.; Gothe, Neha; Olson, Erin A.; Mullen, Sean P.; Fanning, Jason; Motl, Robert W.; Rosengren, Karl; Estabrooks, Paul

    2011-01-01

    The Flexibility, Toning, and Balance (FlexToBa™) Trial is a two-armed randomized controlled trial which will contrast the effects of a DVD-delivered, home-based, physical activity intervention and a Healthy Aging attention control condition on physical activity, functional performance, functional limitations, and quality of life in low active, older adults. This innovative trial will recruit 300 participants across central Illinois who will be randomized into the intervention arm or control arm of the study. The intervention will last 6 months with a 6 month follow-up. Assessments at baseline, post intervention and follow-up will include physical activity (self-report and accelerometry), a battery of functional performance measures, functional limitations, quality of life, and an array of psychological health measures. In addition, measures of external validity will be included to determine public health significance of a successful outcome. Participants will engage in a progressive series of activities focusing on flexibility, strengthening, and balance exercises which are demonstrated by a trained exercise leader and age-appropriate models on a series of DVDs. Delivery of the intervention has its basis in social cognitive theory. The specific aims of the trial are (a) to determine the effects of the DVD-delivered FlexToBa™ program on physical activity, functional performance, functional limitations, and quality of life, (b) to examine the mediators of the relationships between physical activity and functional limitations and quality of life, (c) to assess external validity indicators relative to the intervention, and (d) to determine differential effects of the intervention on psychosocial health measures. PMID:22024470

  14. Sequential Polarity-Reversing Circuit

    NASA Technical Reports Server (NTRS)

    Labaw, Clayton C.

    1994-01-01

    Proposed circuit reverses polarity of electric power supplied to bidirectional dc motor, reversible electro-mechanical actuator, or other device operating in direction depending on polarity. Circuit reverses polarity each time power turned on, without need for additional polarity-reversing or direction signals and circuitry to process them.

  15. Postirradiation Effects In Integrated Circuits

    NASA Technical Reports Server (NTRS)

    Shaw, David C.; Barnes, Charles E.

    1993-01-01

    Two reports discuss postirradiation effects in integrated circuits. Presents examples of postirradiation measurements of performances of integrated circuits of five different types: dual complementary metal oxide/semiconductor (CMOS) flip-flop; CMOS analog multiplier; two CMOS multiplying digital-to-analog converters; electrically erasable programmable read-only memory; and semiconductor/oxide/semiconductor octal buffer driver.

  16. Demonstrations with an "LCR" Circuit

    ERIC Educational Resources Information Center

    Kraftmakher, Yaakov

    2011-01-01

    The "LCR" circuit is an important topic in the course of electricity and magnetism. Papers in this field consider mainly the forced oscillations and resonance. Our aim is to show how to demonstrate the free and self-excited oscillations in an "LCR" circuit. (Contains 4 figures.)

  17. Compact Circuit Preprocesses Accelerometer Output

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr.

    1993-01-01

    Compact electronic circuit transfers dc power to, and preprocesses ac output of, accelerometer and associated preamplifier. Incorporated into accelerometer case during initial fabrication or retrofit onto commercial accelerometer. Made of commercial integrated circuits and other conventional components; made smaller by use of micrologic and surface-mount technology.

  18. Hybrid temperature-monitoring circuit

    NASA Technical Reports Server (NTRS)

    Rinard, G. A.; Steffen, D. A.; Sturm, R. E.

    1979-01-01

    Hybrid circuit developed for use in hand-held vital signs monitor converts resistance of thermistor probe to 3 1/2 digit BCD (binary-coded-decimal) temperature readout. If used alone circuit can form 'stand alone' temperature monitor or can transmit temperature data via telemetry to data acquisition systems.

  19. Time domain analog circuit simulation

    NASA Astrophysics Data System (ADS)

    Fijnvandraat, J. G.; Houben, S. H. M. J.; Ter Maten, E. J. W.; Peters, J. M. F.

    2006-01-01

    Recent developments of new methods for simulating electric circuits are described. Emphasis is put on methods that fit existing datastructures for backward differentiation formulae methods. These methods can be modified to apply to hierarchically organized datastructures, which allows for efficient simulation of large designs of circuits in the electronics industry.

  20. Pharmacokinetics and "RC" Circuit Concepts

    ERIC Educational Resources Information Center

    De Cock, Mieke; Janssen, Paul

    2013-01-01

    Most introductory physics courses include a chapter on "RC" circuits in which the differential equations for the charging and discharging of a capacitor are derived. A number of papers in this journal describe lab experiments dealing with the measurement of different parameters in such "RC" circuits. In this contribution, we…

  1. Dive In to Aquatic Circuits.

    ERIC Educational Resources Information Center

    Goldfarb, Joseph M.

    1995-01-01

    The article presents a method for swimming teachers and coaches to stave off workout boredom in their students by using a circuit in the pool. After explaining how to set up a training circuit, the article describes sample stations and notes important safety precautions. (SM)

  2. Digital circuits using universal logic gates

    NASA Technical Reports Server (NTRS)

    Whitaker, Sterling R. (Inventor); Miles, Lowell H. (Inventor); Cameron, Eric G. (Inventor); Donohoe, Gregory W. (Inventor); Gambles, Jody W. (Inventor)

    2004-01-01

    According to the invention, a digital circuit design embodied in at least one of a structural netlist, a behavioral netlist, a hardware description language netlist, a full-custom ASIC, a semi-custom ASIC, an IP core, an integrated circuit, a hybrid of chips, one or more masks, a FPGA, and a circuit card assembly is disclosed. The digital circuit design includes first and second sub-circuits. The first sub-circuits comprise a first percentage of the digital circuit design and the second sub-circuits comprise a second percentage of the digital circuit design. Each of the second sub-circuits is substantially comprised of one or more kernel circuits. The kernel circuits are comprised of selection circuits. The second percentage is at least 5%. In various embodiments, the second percentage could be at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 95%.

  3. Genetic Dissection of Neural Circuits

    PubMed Central

    Luo, Liqun; Callaway, Edward M.; Svoboda, Karel

    2009-01-01

    Understanding the principles of information processing in neural circuits requires systematic characterization of the participating cell types and their connections, and the ability to measure and perturb their activity. Genetic approaches promise to bring experimental access to complex neural systems, including genetic stalwarts such as the fly and mouse, but also to nongenetic systems such as primates. Together with anatomical and physiological methods, cell-type-specific expression of protein markers and sensors and transducers will be critical to construct circuit diagrams and to measure the activity of genetically defined neurons. Inactivation and activation of genetically defined cell types will establish causal relationships between activity in specific groups of neurons, circuit function, and animal behavior. Genetic analysis thus promises to reveal the logic of the neural circuits in complex brains that guide behaviors. Here we review progress in the genetic analysis of neural circuits and discuss directions for future research and development. PMID:18341986

  4. Demultiplexer circuit for neural stimulation

    DOEpatents

    Wessendorf, Kurt O; Okandan, Murat; Pearson, Sean

    2012-10-09

    A demultiplexer circuit is disclosed which can be used with a conventional neural stimulator to extend the number of electrodes which can be activated. The demultiplexer circuit, which is formed on a semiconductor substrate containing a power supply that provides all the dc electrical power for operation of the circuit, includes digital latches that receive and store addressing information from the neural stimulator one bit at a time. This addressing information is used to program one or more 1:2.sup.N demultiplexers in the demultiplexer circuit which then route neural stimulation signals from the neural stimulator to an electrode array which is connected to the outputs of the 1:2.sup.N demultiplexer. The demultiplexer circuit allows the number of individual electrodes in the electrode array to be increased by a factor of 2.sup.N with N generally being in a range of 2-4.

  5. Twin reservoir heat transfer circuit

    SciTech Connect

    Urch, J.F.

    1986-09-23

    This patent describes a heat transfer means comprising circuitry defining a closed flow path for working fluid; a primary circuit forming part of the path and having two ends at one of which the working fluid is at a high pressure and at the other of which the working fluid is at a low pressure. The circuitry defines a fluid supply reservoir and a fluid collection reservoir disposed respectively at the two ends; ejector means in the primary circuit; a drive fluid inlet, and exhaust outlet and a suction inlet provided on the ejector means. Also included are a branch circuit bridging a section of the primary circuit and an outlet end of the branch circuit connected to the suction inlet of the ejector means.

  6. Electronic design with integrated circuits

    NASA Astrophysics Data System (ADS)

    Comer, D. J.

    The book is concerned with the application of integrated circuits and presents the material actually needed by the system designer to do an effective job. The operational amplifier (op amp) is discussed, taking into account the electronic amplifier, the basic op amp, the practical op amp, analog applications, and digital applications. Digital components are considered along with combinational logic, digital subsystems, the microprocessor, special circuits, communications, and integrated circuit building blocks. Attention is given to logic gates, logic families, multivibrators, the digital computer, digital methods, communicating with a computer, computer organization, register and timing circuits for data transfer, arithmetic circuits, memories, the microprocessor chip, the control unit, communicating with the microprocessor, examples of microprocessor architecture, programming a microprocessor, the voltage-controlled oscillator, the phase-locked loop, analog-to-digital conversion, amplitude modulation, frequency modulation, pulse and digital transmission, the semiconductor diode, the bipolar transistor, and the field-effect transistor.

  7. A comparison of stainless steel Flexofiles and nickel-titanium NiTiFlex files during the shaping of simulated canals.

    PubMed

    Bishop, K; Dummer, P M

    1997-01-01

    The aim of this study was to compare the shaping ability of stainless steel Flexofiles and nickel-titanium NiTiFlex files during the preparation of simulated canals in resin blocks. A total of 80 canals with various angles and position of curvature were prepared by one operator using either Flexofiles or NiTiFlex files in a modified double-flared technique with balanced force method of instrument manipulation. Canal shape was assessed at two stages during the procedure, after apical enlargement to size 30 and subsequently at size 45. Pre- and post-operative images of the canals were taken with a video camera and stored and manipulated in a computer with image analysis software. The presence of canal aberrations and the amount of material removed as a result of preparation were determined from composite images of superimposed pre- and post-operative views. Canal preparation using NiTiFlex files was significantly quicker (P < 0.0001) up to size 30. More instrument failures occurred with Flexofiles (12) compared to NiTiFlex files (7) but there were no statistically significant differences between file type, instrument size or canal shape. Flexofiles created significantly more zips, perforations and ledges; there were no differences in terms of danger zones. Overall, canals prepared with Flexofiles were significantly wider because more material was removed from the outer aspect of the curve at the end-point of preparation and from the inner aspect of the curve at the apex. Under the conditions of this study, preparation with NiTiFlex files was more effective and produced more appropriate canal shapes than Flexofiles. PMID:9477791

  8. 49 CFR 236.728 - Circuit, trap.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, trap. 236.728 Section 236.728... Circuit, trap. A term applied to a circuit used where it is desirable to provide a track circuit but where it is impracticable to maintain a track circuit....

  9. An Electronics Course Emphasizing Circuit Design

    ERIC Educational Resources Information Center

    Bergeson, Haven E.

    1975-01-01

    Describes a one-quarter introductory electronics course in which the students use a variety of inexpensive integrated circuits to design and construct a large number of useful circuits. Presents the subject matter of the course in three parts: linear circuits, digital circuits, and more complex circuits. (GS)

  10. Gate drive latching circuit for an auxiliary resonant commutation circuit

    NASA Technical Reports Server (NTRS)

    Delgado, Eladio Clemente (Inventor); Kheraluwala, Mustansir Hussainy (Inventor)

    1999-01-01

    A gate drive latching circuit for an auxiliary resonant commutation circuit for a power switching inverter includes a current monitor circuit providing a current signal to a pair of analog comparators to implement latching of one of a pair of auxiliary switching devices which are used to provide commutation current for commutating switching inverters in the circuit. Each of the pair of comparators feeds a latching circuit which responds to an active one of the comparators for latching the associated gate drive circuit for one of the pair of auxiliary commutating switches. An initial firing signal is applied to each of the commutating switches to gate each into conduction and the resulting current is monitored to determine current direction and therefore the one of the switches which is carrying current. The comparator provides a latching signal to the one of the auxiliary power switches which is actually conducting current and latches that particular power switch into an on state for the duration of current through the device. The latching circuit is so designed that the only time one of the auxiliary switching devices can be latched on is during the duration of an initial firing command signal.

  11. A circuit to demonstrate phase relationships in RLC circuits

    NASA Astrophysics Data System (ADS)

    Sokol, P. E.; Warren, G.; Zheng, B.; Smith, P.

    2013-05-01

    We have developed a circuit to demonstrate the phase relationships between resistive and reactive elements in series RLC circuits. We utilize a differential amplifier to allow the phases of the three elements and the current to be simultaneously displayed on an inexpensive four channel oscilloscope. We have included a novel circuit that provides a visual indication of the magnitude and direction of the voltage or current using LEDs. This allows the phase relationships to be demonstrated directly using the very intuitive measurement of the brightness of a light.

  12. Nanofluidic Transistor Circuits

    NASA Astrophysics Data System (ADS)

    Chang, Hsueh-Chia; Cheng, Li-Jing; Yan, Yu; Slouka, Zdenek; Senapati, Satyajyoti

    2012-02-01

    Non-equilibrium ion/fluid transport physics across on-chip membranes/nanopores is used to construct rectifying, hysteretic, oscillatory, excitatory and inhibitory nanofluidic elements. Analogs to linear resistors, capacitors, inductors and constant-phase elements were reported earlier (Chang and Yossifon, BMF 2009). Nonlinear rectifier is designed by introducing intra-membrane conductivity gradient and by asymmetric external depletion with a reverse rectification (Yossifon and Chang, PRL, PRE, Europhys Lett 2009-2011). Gating phenomenon is introduced by functionalizing polyelectrolytes whose conformation is field/pH sensitive (Wang, Chang and Zhu, Macromolecules 2010). Surface ion depletion can drive Rubinstein's microvortex instability (Chang, Yossifon and Demekhin, Annual Rev of Fluid Mech, 2012) or Onsager-Wien's water dissociation phenomenon, leading to two distinct overlimiting I-V features. Bipolar membranes exhibit an S-hysteresis due to water dissociation (Cheng and Chang, BMF 2011). Coupling the hysteretic diode with some linear elements result in autonomous ion current oscillations, which undergo classical transitions to chaos. Our integrated nanofluidic circuits are used for molecular sensing, protein separation/concentration, electrospray etc.

  13. Piezo-optomechanical circuits

    NASA Astrophysics Data System (ADS)

    Coimbatore Balram, Krishna; Davanco, Marcelo; Ilic, B. Robert; Srinivasan, Kartik

    Coherent links between the optical, radio frequency (RF), and mechanical domains are critical for applications ranging from quantum state transfer between the RF and optical domains to signal processing in the acoustic domain for microwave photonics. We develop such a piezo optomechanical circuit platform in GaAs, in which localized and interacting 1550 nm photons and 2.4 GHz phonons are combined with photonic and phononic waveguides. GaAs allows us to exploit the photoelastic effect to engineer cavities with strong optomechanical coupling (g0/2 π ~ 1.1 MHz) and the piezoelectric effect to couple RF fields to mechanical motion through surface acoustic waves, which are routed on-chip using phononic crystal waveguides. This platform enables optical readout of electrically-injected mechanical states with an average coherent intracavity phonon number as small as ~0.05 and the ability to drive mechanical motion with equal facility through either the optical or electrical channel. This is used to demonstrate a novel acoustic wave interference effect in which optically-driven motion is completely cancelled by electrically-driven motion, and vice versa. As an application of this, we present time-domain measurements of optically-controlled acoustic pulse propagation. Secondary Affiliation is Maryland Nanocenter, University of Maryland, College Park, MD.

  14. PHOTOSENSITIVE RELAY CONTROL CIRCUIT

    DOEpatents

    Martin, C.F.

    1958-01-14

    adapted for the measurement of the time required for an oscillating member to pass through a preselected number of oscillations, after being damped to a certain maximum amplitude of oscillation. A mirror is attached to the moving member and directs light successively to a photocell which is part of a trigger unit and to first and second photocells which are part of a starter unit, as the member swings to its maximum amplitude. The starter and trigger units comprise thyratrons and relays so interconnected that the trigger circuit, although generating a counter pulse, does not register a count in the counter when the light traverses both photocells of the starter unit. When the amplitude of oscillation of the member decreases to where the second photocell is not transversed, the triggei pulse is received by the counter. The counter taen operates to register the desired number of oscillations and initiates and terminates a timer for measuring the time irterval for the preselected number of oscillations.

  15. Variational integrators for electric circuits

    SciTech Connect

    Ober-Blöbaum, Sina; Tao, Molei; Cheng, Mulin; Owhadi, Houman; Marsden, Jerrold E.

    2013-06-01

    In this contribution, we develop a variational integrator for the simulation of (stochastic and multiscale) electric circuits. When considering the dynamics of an electric circuit, one is faced with three special situations: 1. The system involves external (control) forcing through external (controlled) voltage sources and resistors. 2. The system is constrained via the Kirchhoff current (KCL) and voltage laws (KVL). 3. The Lagrangian is degenerate. Based on a geometric setting, an appropriate variational formulation is presented to model the circuit from which the equations of motion are derived. A time-discrete variational formulation provides an iteration scheme for the simulation of the electric circuit. Dependent on the discretization, the intrinsic degeneracy of the system can be canceled for the discrete variational scheme. In this way, a variational integrator is constructed that gains several advantages compared to standard integration tools for circuits; in particular, a comparison to BDF methods (which are usually the method of choice for the simulation of electric circuits) shows that even for simple LCR circuits, a better energy behavior and frequency spectrum preservation can be observed using the developed variational integrator.

  16. 49 CFR 236.731 - Controller, circuit.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Controller, circuit. A device for opening and closing electric circuits. ... 49 Transportation 4 2014-10-01 2014-10-01 false Controller, circuit. 236.731 Section 236.731 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD...

  17. 49 CFR 236.731 - Controller, circuit.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Controller, circuit. A device for opening and closing electric circuits. ... 49 Transportation 4 2013-10-01 2013-10-01 false Controller, circuit. 236.731 Section 236.731 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD...

  18. 49 CFR 236.731 - Controller, circuit.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Controller, circuit. A device for opening and closing electric circuits. ... 49 Transportation 4 2010-10-01 2010-10-01 false Controller, circuit. 236.731 Section 236.731 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD...

  19. 49 CFR 236.731 - Controller, circuit.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Controller, circuit. A device for opening and closing electric circuits. ... 49 Transportation 4 2011-10-01 2011-10-01 false Controller, circuit. 236.731 Section 236.731 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD...

  20. 49 CFR 236.731 - Controller, circuit.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Controller, circuit. A device for opening and closing electric circuits. ... 49 Transportation 4 2012-10-01 2012-10-01 false Controller, circuit. 236.731 Section 236.731 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD...

  1. Performance analysis of electrical circuits /PANE/

    NASA Technical Reports Server (NTRS)

    Johnson, K. L.; Steinberg, L. L.

    1968-01-01

    Automated statistical and worst case computer program has been designed to perform dc and ac steady circuit analyses. The program determines the worst case circuit performance by solving circuit equations.

  2. 30 CFR 75.800 - High-voltage circuits; circuit breakers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage circuits; circuit breakers. 75.800... § 75.800 High-voltage circuits; circuit breakers. High-voltage circuits entering the underground area of any coal mine shall be protected by suitable circuit breakers of adequate interrupting...

  3. 30 CFR 75.800 - High-voltage circuits; circuit breakers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... with devices to provide protection against under-voltage grounded phase, short circuit, and overcurrent. ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false High-voltage circuits; circuit breakers. 75.800... § 75.800 High-voltage circuits; circuit breakers. High-voltage circuits entering the underground...

  4. Framed 4-graphs: Euler tours, Gauss circuits and rotating circuits

    SciTech Connect

    Il'yutko, Denis P

    2011-09-30

    We consider connected finite 4-valent graphs with the structure of opposite edges at each vertex (framed 4-graphs). For any of such graphs there exist Euler tours, in travelling along which at each vertex we turn from an edge to a nonopposite one (rotating circuits); and at the same time, it is not true that for any such graph there exists an Euler tour passing from an edge to the opposite one at each vertex (a Gauss circuit). The main result of the work is an explicit formula connecting the adjacency matrices of the Gauss circuit and an arbitrary Euler tour. This formula immediately gives us a criterion for the existence of a Gauss circuit on a given framed 4-graph. It turns out that the results are also valid for all symmetric matrices (not just for matrices realisable by a chord diagram). Bibliography: 24 titles.

  5. Framed 4-graphs: Euler tours, Gauss circuits and rotating circuits

    NASA Astrophysics Data System (ADS)

    Il'yutko, Denis P.

    2011-09-01

    We consider connected finite 4-valent graphs with the structure of opposite edges at each vertex (framed 4-graphs). For any of such graphs there exist Euler tours, in travelling along which at each vertex we turn from an edge to a nonopposite one (rotating circuits); and at the same time, it is not true that for any such graph there exists an Euler tour passing from an edge to the opposite one at each vertex (a Gauss circuit). The main result of the work is an explicit formula connecting the adjacency matrices of the Gauss circuit and an arbitrary Euler tour. This formula immediately gives us a criterion for the existence of a Gauss circuit on a given framed 4-graph. It turns out that the results are also valid for all symmetric matrices (not just for matrices realisable by a chord diagram). Bibliography: 24 titles.

  6. Integrated circuits, and design and manufacture thereof

    SciTech Connect

    Auracher, Stefan; Pribbernow, Claus; Hils, Andreas

    2006-04-18

    A representation of a macro for an integrated circuit layout. The representation may define sub-circuit cells of a module. The module may have a predefined functionality. The sub-circuit cells may include at least one reusable circuit cell. The reusable circuit cell may be configured such that when the predefined functionality of the module is not used, the reusable circuit cell is available for re-use.

  7. Ladder supported ring bar circuit

    NASA Technical Reports Server (NTRS)

    Kosmahl, H. G. (Inventor)

    1983-01-01

    An improved slow wave circuit especially useful in backward wave oscillators includes a slow wave circuit in a waveguide. The slow wave circuit is comprised of rings disposed between and attached to respective stubs. The stubs are attached to opposing sidewalls of the waveguide. To the end that opposed, interacting magnetic fields will be established to provide a very high coupling impedance for the slow wave structure, axially orientated bars are connected between rings in alternate spaces and adjacent to the attachment points of stubs. Similarly, axial bars are connected between rings in the spaces which do not include bars and at points adjacent to the attachment of bars.

  8. Searching Circuit For A Servoloop

    NASA Technical Reports Server (NTRS)

    Sigman, E. H.

    1988-01-01

    Feedback error voltage forced into range of stability. Circuit connected in series with error-voltage line of feedback loop. When loop operates normally in stable region, searching circuit does not disturb operation, and error-voltage output of loop filter is control voltage. When servo unlocks and error-voltage output of loop filter wanders into unstable range, searching circuit forces control voltage to sweep through stable region repeatedly until lock recovered. Consists of two halves identical except polarities of some parts in each half opposite of corresponding parts in other half.

  9. Counterpulse railgun energy recovery circuit

    DOEpatents

    Honig, E.M.

    1984-09-28

    The invention presented relates to a high-power pulsing circuit and more particularly to a repetitive pulse inductive energy storage and transfer circuit for an electromagnetic launcher. In an electromagnetic launcher such as a railgun for propelling a projectile at high velocity, a counterpulse energy recovery circuit is employed to transfer stored inductive energy from a source inductor to the railgun inductance to propel the projectile down the railgun. Switching circuitry and an energy transfer capacitor are used to switch the energy back to the source inductor in readiness for a repetitive projectile propelling cycle.

  10. Overpulse railgun energy recovery circuit

    DOEpatents

    Honig, E.M.

    1984-09-28

    The invention presented relates to a high-power pulsing circuit and more particularly to a repetitive pulse inductive energy storage and transfer circuit for an electromagnetic launcher. In an electromagnetic launcher such as a railgun for propelling a projectile at high velocity, an overpulse energy recovery circuit is employed to transfer stored inductive energy from a source inductor to the railgun inductance to propel the projectile down the railgun. Switching circuitry and an energy transfer capacitor are used to switch the energy back to the source inductor in readiness for a repetitive projectile propelling cycle.

  11. Midbrain circuits for defensive behaviour.

    PubMed

    Tovote, Philip; Esposito, Maria Soledad; Botta, Paolo; Chaudun, Fabrice; Fadok, Jonathan P; Markovic, Milica; Wolff, Steffen B E; Ramakrishnan, Charu; Fenno, Lief; Deisseroth, Karl; Herry, Cyril; Arber, Silvia; Lüthi, Andreas

    2016-06-01

    Survival in threatening situations depends on the selection and rapid execution of an appropriate active or passive defensive response, yet the underlying brain circuitry is not understood. Here we use circuit-based optogenetic, in vivo and in vitro electrophysiological, and neuroanatomical tracing methods to define midbrain periaqueductal grey circuits for specific defensive behaviours. We identify an inhibitory pathway from the central nucleus of the amygdala to the ventrolateral periaqueductal grey that produces freezing by disinhibition of ventrolateral periaqueductal grey excitatory outputs to pre-motor targets in the magnocellular nucleus of the medulla. In addition, we provide evidence for anatomical and functional interaction of this freezing pathway with long-range and local circuits mediating flight. Our data define the neuronal circuitry underlying the execution of freezing, an evolutionarily conserved defensive behaviour, which is expressed by many species including fish, rodents and primates. In humans, dysregulation of this 'survival circuit' has been implicated in anxiety-related disorders. PMID:27279213

  12. Noise consideration in RSFQ circuits

    NASA Astrophysics Data System (ADS)

    Kaplunenko, V.

    2002-08-01

    Recently we reported a direct time jitter measurement, obtained using a ring-like Josephson transmission line (JTL). The jitter value of 0.2 ps/ n ( n--number of junctions in JTL) was obtained for the circuit that was fabricated using the 1 kA/cm 2 Hypres process. In this paper, we report the following investigation of the noise impact on rapid single flux quantum circuits in general, and particularly on two types of clock recovery circuits. The study explains the previously obtained results and shows that a wide frequency band clock recovery unit can be made using 50-junctions and a low-yield high-temperature superconductor technology and operating at 50 K. This approach would relatively easily enable us to implement such a circuit using the packaging of Conductus' commercial products for the wireless industry, which include a cryo-cooler, low noise amplifiers, and a high-frequency interface.

  13. Leveling circuits and crustal movements

    NASA Technical Reports Server (NTRS)

    Chi, S. C.; Reilinger, R. E.; Brown, L. D.; Oliver, J. E.

    1980-01-01

    An investigation of further possible vertical crustal movements in the Western United States made with circuit microclosure analysis is presented. The San Andreas fault in Cal., the Nevada seismic zone in Nev., and the Sierra Nevada in Calif. were studied based on supposition that in areas undergoing crustal movement the misclosure for a particular circuit should have the smallest value when the circuit is formed from the most temporarily homogeneous survey data; it should have larger, predictable values when the circuit is closed with surveys conducted at other times. Leveling surveys along the San Andreas fault and the Nevada seismic zone are discussed, noting the possibility of regional tilting in the Great Basin between 1934 and 1955, and of elevation changes in the Northern Nevada Range using results of leveling surveys between Roseville, Cal. and Reno, Nev.

  14. Focal plane infrared readout circuit

    NASA Technical Reports Server (NTRS)

    Pain, Bedabrata (Inventor)

    2002-01-01

    An infrared imager, such as a spectrometer, includes multiple infrared photodetectors and readout circuits for reading out signals from the photodetectors. Each readout circuit includes a buffered direct injection input circuit including a differential amplifier with active feedback provided through an injection transistor. The differential amplifier includes a pair of input transistors, a pair of cascode transistors and a current mirror load. Photocurrent from a photodetector can be injected onto an integration capacitor in the readout circuit with high injection efficiency at high speed. A high speed, low noise, wide dynamic range linear infrared multiplexer array for reading out infrared detectors with large capacitances can be achieved even when short exposure times are used. The effect of image lag can be reduced.

  15. Automated Design of Quantum Circuits

    NASA Technical Reports Server (NTRS)

    Williams, C.; Gray, G.

    1998-01-01

    In order to design a quantum circuit that performs a desired quantum computation, it is necessary to find a decomposition of the unitary matrix that represents that computation in terms of a sequence of quantum gate operations.

  16. Student Conceptions of Simple Circuits.

    ERIC Educational Resources Information Center

    Fredette, Norman; Lochhead, John

    1980-01-01

    Investigates some conceptual difficulties which college students have with regard to simple direct current circuits. The clinical interview technique was used with 57 students in a freshman level engineering course. (HM)

  17. Principles of Genetic Circuit Design

    PubMed Central

    Brophy, Jennifer A.N.; Voigt, Christopher A.

    2014-01-01

    Cells are able to navigate environments, communicate, and build complex patterns by initiating gene expression in response to specific signals. Engineers need to harness this capability to program cells to perform tasks or build chemicals and materials that match the complexity seen in nature. This review describes new tools that aid the construction of genetic circuits. We show how circuit dynamics can be influenced by the choice of regulators and changed with expression “tuning knobs.” We collate the failure modes encountered when assembling circuits, quantify their impact on performance, and review mitigation efforts. Finally, we discuss the constraints that arise from operating within a living cell. Collectively, better tools, well-characterized parts, and a comprehensive understanding of how to compose circuits are leading to a breakthrough in the ability to program living cells for advanced applications, from living therapeutics to the atomic manufacturing of functional materials. PMID:24781324

  18. Detector verifier for circuit analyzers

    NASA Technical Reports Server (NTRS)

    Pope, D. L.; Wooters, R. L.

    1980-01-01

    Economical tool checks operation of automatic circuit analyzer. Each loop is addressed directly from analyzer console by switching internal analyzer bridge to resistance equal that of connecting cable plus specified limiting test value. Procedure verifies whether detected faults in circuit under test are actually due to analyzer malfunction. Standard-length universal test cables make it possible to shift detector tool from cable to cable without resistance compensation.

  19. Reverse engineering of integrated circuits

    DOEpatents

    Chisholm, Gregory H.; Eckmann, Steven T.; Lain, Christopher M.; Veroff, Robert L.

    2003-01-01

    Software and a method therein to analyze circuits. The software comprises several tools, each of which perform particular functions in the Reverse Engineering process. The analyst, through a standard interface, directs each tool to the portion of the task to which it is most well suited, rendering previously intractable problems solvable. The tools are generally used iteratively to produce a successively more abstract picture of a circuit, about which incomplete a priori knowledge exists.

  20. Sutures, Sinkers, Shear zones and Sills: Cryptic Targets and Explicit Strategies for EARTHSCOPE FlexArray in the East

    NASA Astrophysics Data System (ADS)

    Brown, L. D.

    2006-05-01

    Given the 3D framework represented by EarthScope's USArray as it scans eastward, the strategic challenge falls to defining cost-effective deployments of FlexArray to address specific lithospheric targets. Previous deep geophysical surveys (e.g. COCORP, USGS, GLIMPCE, et al.) provide guidance not only in framing the geological issues involved, but in designing field experiments that overcome the limitations of previous work. Opportunities highlighted by these precursor studies include: a) Collisional sutures (e.g. Brunswick Anomaly/Suwannee terrane) which lie buried beneath overthrust terranes/ younger sedimentary covers. Signal penetration in previous controlled source surveys has been insufficient. High resolution passive surveys designed to map intralithospheric detachments, Moho, and mantle subduction scars is needed to validate the extrapolations of the existing upper crustal information; b) Intracratonic basins and domes (e.g. Michigan Basin, Adirondack Dome) are perhaps the greatest geological mystery hosted in the east. Previous geophysical studies have lacked the resolution or penetration needed to identify the buoyancy drivers presumed to be responsible for such structures. It is likely that these drivers lie in the upper mantle and will require detailed velocity imaging to recognized. c) Distributed shear fabrics are a defining characteristic of the deep crust in many deformation zones (e.g. Grenville Front). Detailed mapping of crustal anisotropy associated with such shear zones should help delineate ductile flow directions associated with the orogenies that accreted the eastern U.S. 3 component, 3D active+passive surveys are needed to obtain definitive remote measures of such vector characteristics in the deep crust. d) Extensive reflectors in the central U.S. may mark important buried Precambrian basins and/or sill complexes. If the latter, the magmatic roots of those systems remain unrecognized, as does their volumetric contribution to crustal growth

  1. Receiver Gain Modulation Circuit

    NASA Technical Reports Server (NTRS)

    Jones, Hollis; Racette, Paul; Walker, David; Gu, Dazhen

    2011-01-01

    A receiver gain modulation circuit (RGMC) was developed that modulates the power gain of the output of a radiometer receiver with a test signal. As the radiometer receiver switches between calibration noise references, the test signal is mixed with the calibrated noise and thus produces an ensemble set of measurements from which ensemble statistical analysis can be used to extract statistical information about the test signal. The RGMC is an enabling technology of the ensemble detector. As a key component for achieving ensemble detection and analysis, the RGMC has broad aeronautical and space applications. The RGMC can be used to test and develop new calibration algorithms, for example, to detect gain anomalies, and/or correct for slow drifts that affect climate-quality measurements over an accelerated time scale. A generalized approach to analyzing radiometer system designs yields a mathematical treatment of noise reference measurements in calibration algorithms. By treating the measurements from the different noise references as ensemble samples of the receiver state, i.e. receiver gain, a quantitative description of the non-stationary properties of the underlying receiver fluctuations can be derived. Excellent agreement has been obtained between model calculations and radiometric measurements. The mathematical formulation is equivalent to modulating the gain of a stable receiver with an externally generated signal and is the basis for ensemble detection and analysis (EDA). The concept of generating ensemble data sets using an ensemble detector is similar to the ensemble data sets generated as part of ensemble empirical mode decomposition (EEMD) with exception of a key distinguishing factor. EEMD adds noise to the signal under study whereas EDA mixes the signal with calibrated noise. It is mixing with calibrated noise that permits the measurement of temporal-functional variability of uncertainty in the underlying process. The RGMC permits the evaluation of EDA by

  2. Design of a satellite end-to-end mission performance simulator for imaging spectrometers and its application to the ESA's FLEX/Sentinel-3 tandem mission

    NASA Astrophysics Data System (ADS)

    Vicent, Jorge; Sabater, Neus; Tenjo, Carolina; Acarreta, Juan R.; Manzano, María.; Rivera, Juan P.; Jurado, Pedro; Franco, Raffaella; Alonso, Luis; Moreno, Jose

    2015-09-01

    The performance analysis of a satellite mission requires specific tools that can simulate the behavior of the platform; its payload; and the acquisition of scientific data from synthetic scenes. These software tools, called End-to-End Mission Performance Simulators (E2ES), are promoted by the European Space Agency (ESA) with the goal of consolidating the instrument and mission requirements as well as optimizing the implemented data processing algorithms. Nevertheless, most developed E2ES are designed for a specific satellite mission and can hardly be adapted to other satellite missions. In the frame of ESA's FLEX mission activities, an E2ES is being developed based on a generic architecture for passive optical missions. FLEX E2ES implements a state-of-the-art synthetic scene generator that is coupled with dedicated algorithms that model the platform and instrument characteristics. This work will describe the flexibility of the FLEX E2ES to simulate complex synthetic scenes with a variety of land cover classes, topography and cloud cover that are observed separately by each instrument (FLORIS, OLCI and SLSTR). The implemented algorithms allows modelling the sensor behavior, i.e. the spectral/spatial resampling of the input scene; the geometry of acquisition; the sensor noises and non-uniformity effects (e.g. stray-light, spectral smile and radiometric noise); and the full retrieval scheme up to Level-2 products. It is expected that the design methodology implemented in FLEX E2ES can be used as baseline for other imaging spectrometer missions and will be further expanded towards a generic E2ES software tool.

  3. Anatomical study of the posterior cruciate ligament with the knee flexed at 90°☆☆☆

    PubMed Central

    Cho, Daniel Kyubin; Rosa, Sthéphano Pellizzaro; Prestes, Guilherme Bello; da Cunha, Luiz Antônio Munhoz; de Moura, Márcio Fernando Aparecido; Stieven Filho, Edmar

    2014-01-01

    Objective To study the anatomy of the posterior cruciate ligament (PCL) and define anatomical parameters with the knee flexed at 90°. Methods Eight knees from cadavers were dissected in order to make measurements from the center of the anterolateral band to the roof (AL1), from the center of the anterolateral band to the anterior cartilage (AL2), from the center of the posteromedial band to the roof (PM1), from the center of the posteromedial band to the anterior cartilage (PM2), from the center of the tibial insertion to the medial region of the tibia (TIM), from the center of the tibial insertion to the lateral region of the tibia (TIL), from the center of the medial insertion to the medial meniscus (IMM) and the width of the origin of the PCL (WO). To obtain the results from each anatomical structure, the means and standard deviations of the measurements were calculated. Results The measurements in millimeters that were found were AL1, 6.2; AL2, 4.9; PM1, 11.7; PM2, 5.5; TIM, 32.5; TIL, 40.6; IMM, 9.4; and WO, 32.5. Conclusions The PCL has an extensive origin. The center of the anterolateral band is 6 mm from the roof and 5 mm from the anterior cartilage of the knee. The tibial insertion is slightly medial and 10 mm distal to the posterior cornu of the medial meniscus. PMID:26229851

  4. 46 CFR 169.670 - Circuit breakers.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Circuit breakers. 169.670 Section 169.670 Shipping COAST... Gross Tons § 169.670 Circuit breakers. Each circuit breaker must be of the manually reset type designed for— (a) Inverse time delay; (b) Instantaneous short circuit protection; and (c) Repeated opening...

  5. 46 CFR 169.670 - Circuit breakers.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Circuit breakers. 169.670 Section 169.670 Shipping COAST... Gross Tons § 169.670 Circuit breakers. Each circuit breaker must be of the manually reset type designed for— (a) Inverse time delay; (b) Instantaneous short circuit protection; and (c) Repeated opening...

  6. 46 CFR 169.670 - Circuit breakers.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Circuit breakers. 169.670 Section 169.670 Shipping COAST... Gross Tons § 169.670 Circuit breakers. Each circuit breaker must be of the manually reset type designed for— (a) Inverse time delay; (b) Instantaneous short circuit protection; and (c) Repeated opening...

  7. 46 CFR 169.670 - Circuit breakers.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Circuit breakers. 169.670 Section 169.670 Shipping COAST... Gross Tons § 169.670 Circuit breakers. Each circuit breaker must be of the manually reset type designed for— (a) Inverse time delay; (b) Instantaneous short circuit protection; and (c) Repeated opening...

  8. Bypassing An Open-Circuit Power Cell

    NASA Technical Reports Server (NTRS)

    Wannemacher, Harry E.

    1994-01-01

    Collection of bypass circuits enables battery consisting series string of cells to continue to function when one of its cells fails in open-circuit (high-resistance) condition. Basic idea simply to shunt current around defective cell to prevent open circuit from turning off battery altogether. Bypass circuits dissipate little power and are nearly immune to false activation.

  9. Improved self arbitrated VLSI asynchronous circuits

    NASA Technical Reports Server (NTRS)

    Winterrowd, P.

    1991-01-01

    This paper introduces an improved method for designing the class of CMOS VLSI asynchronous sequential circuits introduced in the paper by Sterling R. Whitaker and Gary K. Maki, 'Self Arbitrated VLSI Asynchronous Circuits.' Of main interest here is the simple design by inspection rules that arise from these circuits. This paper presents a variation on these circuits which reduces the number of transistors required.

  10. Tunable circuit for tunable capacitor devices

    SciTech Connect

    Rivkina, Tatiana; Ginley, David S.

    2006-09-19

    A tunable circuit (10) for a capacitively tunable capacitor device (12) is provided. The tunable circuit (10) comprises a tunable circuit element (14) and a non-tunable dielectric element (16) coupled to the tunable circuit element (16). A tunable capacitor device (12) and a method for increasing the figure of merit in a tunable capacitor device (12) are also provided.

  11. Difference-Equation/Flow-Graph Circuit Analysis

    NASA Technical Reports Server (NTRS)

    Mcvey, I. M.

    1988-01-01

    Numerical technique enables rapid, approximate analyses of electronic circuits containing linear and nonlinear elements. Practiced in variety of computer languages on large and small computers; for circuits simple enough, programmable hand calculators used. Although some combinations of circuit elements make numerical solutions diverge, enables quick identification of divergence and correction of circuit models to make solutions converge.

  12. Multi-Layer E-Textile Circuits

    NASA Technical Reports Server (NTRS)

    Dunne, Lucy E.; Bibeau, Kaila; Mulligan, Lucie; Frith, Ashton; Simon, Cory

    2012-01-01

    Stitched e-textile circuits facilitate wearable, flexible, comfortable wearable technology. However, while stitched methods of e-textile circuits are common, multi-layer circuit creation remains a challenge. Here, we present methods of stitched multi-layer circuit creation using accessible tools and techniques.

  13. Modular integration of electronics and microfluidic systems using flexible printed circuit boards.

    PubMed

    Wu, Amy; Wang, Lisen; Jensen, Erik; Mathies, Richard; Boser, Bernhard

    2010-02-21

    Microfluidic systems offer an attractive alternative to conventional wet chemical methods with benefits including reduced sample and reagent volumes, shorter reaction times, high-throughput, automation, and low cost. However, most present microfluidic systems rely on external means to analyze reaction products. This substantially adds to the size, complexity, and cost of the overall system. Electronic detection based on sub-millimetre size integrated circuits (ICs) has been demonstrated for a wide range of targets including nucleic and amino acids, but deployment of this technology to date has been limited due to the lack of a flexible process to integrate these chips within microfluidic devices. This paper presents a modular and inexpensive process to integrate ICs with microfluidic systems based on standard printed circuit board (PCB) technology to assemble the independently designed microfluidic and electronic components. The integrated system can accommodate multiple chips of different sizes bonded to glass or PDMS microfluidic systems. Since IC chips and flex PCB manufacturing and assembly are industry standards with low cost, the integrated system is economical for both laboratory and point-of-care settings. PMID:20126694

  14. [Successful Intubation in a Patient with Limited Oral Opening by Using a Combination of the Parker Flex-IT™ Stylet and McGRATH® MAC Laryngoscopy].

    PubMed

    Ueshima, Hironobu; Terao, Kazuhisa; Kitamura, Akira

    2015-10-01

    A 74-year-old female patient underwent a coil embolization for an unruptured cerebral aneurysm. A routine anesthetic protocol was devised as there was no risk of a difficult airway. We attempted to intubate by using direct laryngoscopy but were unable to because the mouth only opened approximately one finger-breadth. We then attempted to intubate using Mc-GRATH® MAC laryngoscopy; the McGRATH® MAC laryngoscope could be inserted orally by force, but a tracheal tube and stylet could not been guided into the glottis. We changed the stylet to a Parker Flex-IT™ Stylet (Parker Medical, CO, USA), which can be freely curved by pushing the sum button on the top of the stylet. As a result, easy intubation was possible, and the DLT was maneuvered at a proper angle while examining the vocal cords by using the Parker Flex-IT™ Stylet In conclusion, when a McGRATH® MAC laryngoscope cannot be operated freely in the oral cavity owing to a limited oral opening, we can instead intubate easily and effectively by using a combination of a Parker Flex-IT™ Stylet and the McGRATH® MAC video laryngoscope. PMID:26742408

  15. Investigation of a FAST-OrcaFlex Coupling Module for Integrating Turbine and Mooring Dynamics of Offshore Floating Wind Turbines: Preprint

    SciTech Connect

    Masciola, M.; Robertson, A.; Jonkman, J.; Driscoll, F.

    2011-10-01

    To enable offshore floating wind turbine design, the following are required: accurate modeling of the wind turbine structural dynamics, aerodynamics, platform hydrodynamics, a mooring system, and control algorithms. Mooring and anchor design can appreciably affect the dynamic response of offshore wind platforms that are subject to environmental loads. From an engineering perspective, system behavior and line loads must be studied well to ensure the overall design is fit for the intended purpose. FAST (Fatigue, Aerodynamics, Structures and Turbulence) is a comprehensive simulation tool used for modeling land-based and offshore wind turbines. In the case of a floating turbine, continuous cable theory is used to emulate mooring line dynamics. Higher modeling fidelity can be gained through the use of finite element mooring theory. This can be achieved through the FASTlink coupling module, which couples FAST with OrcaFlex, a commercial simulation tool used for modeling mooring line dynamics. In this application, FAST is responsible for capturing the aerodynamic loads and flexure of the wind turbine and its tower, and OrcaFlex models the mooring line and hydrodynamic effects below the water surface. This paper investigates the accuracy and stability of the FAST/OrcaFlex coupling operation.

  16. Mechanism for interfacial adhesion strength of an ion beam mixed Cu/polyimide with a thin buffer layer

    NASA Astrophysics Data System (ADS)

    Chang, G. S.; Chae, K. H.; Whang, C. N.; Kurmaev, E. Z.; Zatsepin, D. A.; Winarski, R. P.; Ederer, D. L.; Moewes, A.; Lee, Y. P.

    1999-01-01

    A Cu (400 Å)/Al (50 Å)/polyimide system showed larger adhesion strength than that of Cu (400 Å)/polyimide after N2+ ion beam mixing. X-ray emission spectroscopy was performed to elucidate the mechanism of adhesion enhancement of the ion beam mixed Cu (400 Å)/polyimide with a thin Al buffer layer. Cu L2,3 x-ray emission spectra showed the formation of a CuAl2O4 layer which is strongly correlated with the large adhesion strength of a Cu/Al/polyimide. A decrease in adhesion strength at an ion dose higher than 5×1015cm-2 was also explained by the formation of an amorphous carbon. This was understood by investigating C Kα x-ray emission spectra. The overall spectroscopic results were in accordance with the behavior of quantitative adhesion strength.

  17. Digital first order hold circuit

    NASA Technical Reports Server (NTRS)

    Chan, Fred N. (Inventor); Wensley, Gerald J. (Inventor)

    1989-01-01

    There is provided a digitally controlled first order hold circuit and waveform synthesizer for digitally controlling the representation of a function over an approximation interval. In accordance with the operation of the invention, the first order hold circuit and waveform generator receives a digital data input signal which contains initial condition data, up/down data, and slope data for the approximation interval. The initial condition data is loaded into an up/down counter which is incremented using counting data at a rate depending on the value of the slope data and in a direction depending on the value of the up-down data. In order to minimize delays arising from data acquistion, two frequency synthesizer circuits are provided such that one frequency synthesizer provides counting data while the other frequency synthesizer receives slope data. During alternating intervals, the other frequency synthesizer circuit provides counting data while the other circuit receives slope data. In addition, long length data input signals covering a plurality of approximation intervals are provided to reduce the demands on a main system central processing unit.

  18. Bioluminescent bioreporter integrated circuits (BBICs)

    NASA Astrophysics Data System (ADS)

    Simpson, Michael L.; Sayler, Gary S.; Nivens, David; Ripp, Steve; Paulus, Michael J.; Jellison, Gerald E.

    1998-07-01

    As the workhorse of the integrated circuit (IC) industry, the capabilities of CMOS have been expanded well beyond the original applications. The full spectrum of analog circuits from switched-capacitor filters to microwave circuit blocks, and from general-purpose operational amplifiers to sub- nanosecond analog timing circuits for nuclear physics experiments have been implemented in CMOS. This technology has also made in-roads into the growing area of monolithic sensors with devices such as active-pixel sensors and other electro-optical detection devices. While many of the processes used for MEMS fabrication are not compatible with the CMOS IC process, depositing a sensor material onto a previously fabricated CMOS circuit can create a very useful category of sensors. In this work we report a chemical sensor composed of bioluminescent bioreporters (genetically engineered bacteria) deposited onto a micro-luminometer fabricated in a standard CMOS IC process. The bioreporter used for this work emitted 490-nm light when exposed to toluene. This luminescence was detected by the micro- luminometer giving an indication of the concentration of toluene. Other bioluminescent bioreporters sensitive to explosives, mercury, and other organic chemicals and heavy metals have been reported. These could be incorporated (individually or in combination) with the micro-luminometer reported here to form a variety of chemical sensors.

  19. Decoupling with Random Quantum Circuits

    NASA Astrophysics Data System (ADS)

    Brown, Winton; Fawzi, Omar

    2015-12-01

    Decoupling has become a central concept in quantum information theory, with applications including proving coding theorems, randomness extraction and the study of conditions for reaching thermal equilibrium. However, our understanding of the dynamics that lead to decoupling is limited. In fact, the only families of transformations that are known to lead to decoupling are (approximate) unitary two-designs, i.e., measures over the unitary group that behave like the Haar measure as far as the first two moments are concerned. Such families include for example random quantum circuits with O( n 2) gates, where n is the number of qubits in the system under consideration. In fact, all known constructions of decoupling circuits use Ω( n 2) gates. Here, we prove that random quantum circuits with O( n log2 n) gates satisfy an essentially optimal decoupling theorem. In addition, these circuits can be implemented in depth O(log3 n). This proves that decoupling can happen in a time that scales polylogarithmically in the number of particles in the system, provided all the particles are allowed to interact. Our proof does not proceed by showing that such circuits are approximate two-designs in the usual sense, but rather we directly analyze the decoupling property.

  20. Neurotrophins and spinal circuit function

    PubMed Central

    Boyce, Vanessa S.; Mendell, Lorne M.

    2014-01-01

    Work early in the last century emphasized the stereotyped activity of spinal circuits based on studies of reflexes. However, the last several decades have focused on the plasticity of these spinal circuits. These considerations began with studies of the effects of monoamines on descending and reflex circuits. In recent years new classes of compounds called growth factors that are found in peripheral nerves and the spinal cord have been shown to affect circuit behavior in the spinal cord. In this review we will focus on the effects of neurotrophins, particularly nerve growth factor (NGF), brain derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3), on spinal circuits. We also discuss evidence that these molecules can modify functions including nociceptive behavior, motor reflexes and stepping behavior. Since these substances and their receptors are normally present in the spinal cord, they could potentially be useful in improving function in disease states and after injury. Here we review recent findings relevant to these translational issues. PMID:24926235

  1. Normal Development of Brain Circuits

    PubMed Central

    Tau, Gregory Z; Peterson, Bradley S

    2010-01-01

    Spanning functions from the simplest reflex arc to complex cognitive processes, neural circuits have diverse functional roles. In the cerebral cortex, functional domains such as visual processing, attention, memory, and cognitive control rely on the development of distinct yet interconnected sets of anatomically distributed cortical and subcortical regions. The developmental organization of these circuits is a remarkably complex process that is influenced by genetic predispositions, environmental events, and neuroplastic responses to experiential demand that modulates connectivity and communication among neurons, within individual brain regions and circuits, and across neural pathways. Recent advances in neuroimaging and computational neurobiology, together with traditional investigational approaches such as histological studies and cellular and molecular biology, have been invaluable in improving our understanding of these developmental processes in humans in both health and illness. To contextualize the developmental origins of a wide array of neuropsychiatric illnesses, this review describes the development and maturation of neural circuits from the first synapse through critical periods of vulnerability and opportunity to the emergent capacity for cognitive and behavioral regulation, and finally the dynamic interplay across levels of circuit organization and developmental epochs. PMID:19794405

  2. Introduction to lethal circuit transformations

    NASA Astrophysics Data System (ADS)

    Fišer, Petr; Schmidt, Jan

    2015-12-01

    Logic optimization is a process that takes a logic circuit description (Boolean network) as an input and tries to refine it, to reduce its size and/or depth. An ideal optimization process should be able to devise an optimum implementation of a network in a reasonable time, given any circuit structure at the input. However, there are cases where it completely fails to produce even near-optimum solutions. Such cases are typically induced by non-standard circuit structure modifications. Surprisingly enough, such deviated structures are frequently present in standard benchmark sets too. We may only wonder whether it is an intention of the benchmarks creators, or just an unlucky coincidence. Even though synthesis tools should be primarily well suited for practical circuits, there is no guarantee that, e.g., a higher-level synthesis process will not generate such unlucky structures. Here we present examples of circuit transformations that lead to failure of most of state-of-the-art logic synthesis and optimization processes, both academic and commercial, and suggest actions to mitigate the disturbing effects.

  3. Architecture and algorithm of a circuit simulator

    NASA Astrophysics Data System (ADS)

    Marranghello, Norian; Damiani, Furio

    1990-11-01

    Software-based circuit simulators had a ten-fold speed improvement in the last 15 years. Despite this they are not fast enough to cost- effectively deal with current VLSI circuits. In this paper we describe the current status of the ABACUS circuit simulator project, which takes advantage of both a dedicated hardware to speed up circuit simulation and a new methodology, where each parallel processor behaves like a circuit element.

  4. 30 CFR 75.518 - Electric equipment and circuits; overload and short circuit protection.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Equipment-General § 75.518 Electric equipment and circuits; overload and short circuit protection. Automatic... electric equipment and circuits against short circuit and overloads. Three-phase motors on all electric... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electric equipment and circuits; overload...

  5. 30 CFR 75.518 - Electric equipment and circuits; overload and short circuit protection.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Equipment-General § 75.518 Electric equipment and circuits; overload and short circuit protection. Automatic... electric equipment and circuits against short circuit and overloads. Three-phase motors on all electric... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electric equipment and circuits; overload...

  6. 30 CFR 75.518 - Electric equipment and circuits; overload and short circuit protection.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Equipment-General § 75.518 Electric equipment and circuits; overload and short circuit protection. Automatic... electric equipment and circuits against short circuit and overloads. Three-phase motors on all electric... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electric equipment and circuits; overload...

  7. 30 CFR 75.518 - Electric equipment and circuits; overload and short circuit protection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Equipment-General § 75.518 Electric equipment and circuits; overload and short circuit protection. Automatic... electric equipment and circuits against short circuit and overloads. Three-phase motors on all electric... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electric equipment and circuits; overload...

  8. 30 CFR 75.518 - Electric equipment and circuits; overload and short circuit protection.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Equipment-General § 75.518 Electric equipment and circuits; overload and short circuit protection. Automatic... electric equipment and circuits against short circuit and overloads. Three-phase motors on all electric... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electric equipment and circuits; overload...

  9. 30 CFR 77.800 - High-voltage circuits; circuit breakers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage circuits; circuit breakers. 77.800... COAL MINES Surface High-Voltage Distribution § 77.800 High-voltage circuits; circuit breakers. High-voltage circuits supplying power to portable or mobile equipment shall be protected by suitable...

  10. 49 CFR 236.5 - Design of control circuits on closed circuit principle.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Design of control circuits on closed circuit..., AND APPLIANCES Rules and Instructions: All Systems General § 236.5 Design of control circuits on closed circuit principle. All control circuits the functioning of which affects safety of train...

  11. 30 CFR 77.800 - High-voltage circuits; circuit breakers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... devices to provide protection against under voltage, grounded phase, short circuit and overcurrent. High... 30 Mineral Resources 1 2011-07-01 2011-07-01 false High-voltage circuits; circuit breakers. 77.800... COAL MINES Surface High-Voltage Distribution § 77.800 High-voltage circuits; circuit breakers....

  12. 30 CFR 75.601-1 - Short circuit protection; ratings and settings of circuit breakers.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Short circuit protection; ratings and settings... Trailing Cables § 75.601-1 Short circuit protection; ratings and settings of circuit breakers. Circuit breakers providing short circuit protection for trailing cables shall be set so as not to exceed...

  13. 30 CFR 75.601-1 - Short circuit protection; ratings and settings of circuit breakers.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit protection; ratings and settings... Trailing Cables § 75.601-1 Short circuit protection; ratings and settings of circuit breakers. Circuit breakers providing short circuit protection for trailing cables shall be set so as not to exceed...

  14. Nuclear sensor signal processing circuit

    DOEpatents

    Kallenbach, Gene A.; Noda, Frank T.; Mitchell, Dean J.; Etzkin, Joshua L.

    2007-02-20

    An apparatus and method are disclosed for a compact and temperature-insensitive nuclear sensor that can be calibrated with a non-hazardous radioactive sample. The nuclear sensor includes a gamma ray sensor that generates tail pulses from radioactive samples. An analog conditioning circuit conditions the tail-pulse signals from the gamma ray sensor, and a tail-pulse simulator circuit generates a plurality of simulated tail-pulse signals. A computer system processes the tail pulses from the gamma ray sensor and the simulated tail pulses from the tail-pulse simulator circuit. The nuclear sensor is calibrated under the control of the computer. The offset is adjusted using the simulated tail pulses. Since the offset is set to zero or near zero, the sensor gain can be adjusted with a non-hazardous radioactive source such as, for example, naturally occurring radiation and potassium chloride.

  15. Design automation for integrated circuits

    NASA Astrophysics Data System (ADS)

    Newell, S. B.; de Geus, A. J.; Rohrer, R. A.

    1983-04-01

    Consideration is given to the development status of the use of computers in automated integrated circuit design methods, which promise the minimization of both design time and design error incidence. Integrated circuit design encompasses two major tasks: error specification, in which the goal is a logic diagram that accurately represents the desired electronic function, and physical specification, in which the goal is an exact description of the physical locations of all circuit elements and their interconnections on the chip. Design automation not only saves money by reducing design and fabrication time, but also helps the community of systems and logic designers to work more innovatively. Attention is given to established design automation methodologies, programmable logic arrays, and design shortcuts.

  16. Riding the circuit for IRP

    SciTech Connect

    Mashaw, R.

    1996-09-01

    In its original usage, the term {open_quotes}circuit rider{close_quotes} described a minister supported by several congregations, who rode from rural church to rural church spreading religion. Today, thanks to a grant from the Department of Energy, there`s a new kind of circuit rider at work in small communities and rural areas, spreading the gospel of integrated resource planning. The concept of the circuit rider was advanced in 1994 by a coalition of associations, private businesses and government agencies, including the American Public Power Association, the National Rural Electric Cooperative Association, the federal power marketing agencies and the National Renewable Energy Laboratory. The group proposed to DOE the creation of a program for the advancement of integrated resource planning (IRP) in public power, designed to extend the resources and capabilities of publicly and cooperatively owned utilities in IRP by offering a several types of assistance, including training, direct consultation and publications.

  17. Counterpulse railgun energy recovery circuit

    SciTech Connect

    Honig, E.M.

    1986-02-25

    This patent describes a counterpulse railgun energy recovery circuit for propelling a projectile along a railgun the counterpulse railgun energy recovery circuit consists of: a railgun having an effective inductance; a source inductor initially charged to an initial current; current means for initially charging the source inductor to the initial current; first current-zero type switching means; second current-zero type switching; third current-zero type switching; muzzle current-zero type switching means; transfer capacitor, the transfer capacitor is for cooperating with the first, second, third, and muzzle current-zero type switching means for providing a resonant circuit for transferring current from the source inductor to the effective inductance of the railgun during the propelling of a projectile along the railgun and for returning current from the effective inductance of the railgun to the source inductance after the projectile has exited the railgun.

  18. Additive Manufacturing of Hybrid Circuits

    NASA Astrophysics Data System (ADS)

    Sarobol, Pylin; Cook, Adam; Clem, Paul G.; Keicher, David; Hirschfeld, Deidre; Hall, Aaron C.; Bell, Nelson S.

    2016-07-01

    There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects. Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. Finally, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes.

  19. Vertically Integrated Circuits at Fermilab

    SciTech Connect

    Deptuch, Grzegorz; Demarteau, Marcel; Hoff, James; Lipton, Ronald; Shenai, Alpana; Trimpl, Marcel; Yarema, Raymond; Zimmerman, Tom; /Fermilab

    2009-01-01

    The exploration of the vertically integrated circuits, also commonly known as 3D-IC technology, for applications in radiation detection started at Fermilab in 2006. This paper examines the opportunities that vertical integration offers by looking at various 3D designs that have been completed by Fermilab. The emphasis is on opportunities that are presented by through silicon vias (TSV), wafer and circuit thinning and finally fusion bonding techniques to replace conventional bump bonding. Early work by Fermilab has led to an international consortium for the development of 3D-IC circuits for High Energy Physics. The consortium has submitted over 25 different designs for the Fermilab organized MPW run organized for the first time.

  20. Pulsed thyristor trigger control circuit

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1984-01-01

    A trigger control circuit is provided for producing firing pulses for the thyristor of a thyristor control system such as a power factor controller. The control circuit overcomes thyristor triggering problems involved with the current lag associated with controlling inductive loads and utilizes a phase difference signal, already present in the power factor controller, in deriving a signal for inhibiting generation of a firing pulse until no load current is flowing from the preceding half cycle and thereby ensuring that the thyristor is triggered on during each half cycle.

  1. Circuit breaker lock out assembly

    DOEpatents

    Gordy, Wade T.

    1984-01-01

    A lock out assembly for a circuit breaker which consists of a generally step-shaped unitary base with an aperture in the small portion of the step-shaped base and a roughly "S" shaped retaining pin which loops through the large portion of the step-shaped base. The lock out assembly is adapted to fit over a circuit breaker with the handle switch projecting through the aperture, and the retaining pin projecting into an opening of the handle switch, preventing removal.

  2. Programming languages for circuit design.

    PubMed

    Pedersen, Michael; Yordanov, Boyan

    2015-01-01

    This chapter provides an overview of a programming language for Genetic Engineering of Cells (GEC). A GEC program specifies a genetic circuit at a high level of abstraction through constraints on otherwise unspecified DNA parts. The GEC compiler then selects parts which satisfy the constraints from a given parts database. GEC further provides more conventional programming language constructs for abstraction, e.g., through modularity. The GEC language and compiler is available through a Web tool which also provides functionality, e.g., for simulation of designed circuits. PMID:25487094

  3. Electrochemical planarization for microelectronic circuits

    SciTech Connect

    Contolini, R.J.; Mayer, S.T.; Bernhardt, A.F.

    1993-03-25

    The need for flatter and smoother surfaces (planarization) in microelectronic circuits increases as the number of metal levels in ultra large scale integrated (ULSI) circuits increases. At Lawrence Livermore National Laboratory, the authors have developed an electrochemical planarization process that fills vias and trenches with metal (without voids) and subsequently planarizes the surface. Use is made of plasma-enhanced chemical vapor deposition (PECVD) of SiO[sub 2] for the dielectric layers and electroplated copper for the metalization. This report describes the advantages of this process over existing techniques, possibilities for collaboration, and previous technology transfer.

  4. Electrochemical planarization for microelectronic circuits

    NASA Astrophysics Data System (ADS)

    Contolini, R. J.; Mayer, S. T.; Bernhardt, A. F.

    1993-03-01

    The need for flatter and smoother surfaces (planarization) in microelectronic circuits increases as the number of metal levels in ultra large scale integrated (ULSI) circuits increases. At Lawrence Livermore National Laboratory, the authors have developed an electrochemical planarization process that fills vias and trenches with metal (without voids) and subsequently planarizes the surface. Use is made of plasma-enhanced chemical vapor deposition (PECVD) of SiO2 for the dielectric layers and electroplated copper for the metalization. This report describes the advantages of this process over existing techniques, possibilities for collaboration, and previous technology transfer.

  5. Logic synthesis of cascade circuits

    NASA Astrophysics Data System (ADS)

    Zakrevskii, A. D.

    The work reviews aspects of the logic design of cascade circuits, particularly programmable logic matrices. Effective methods for solving various problems of the analysis and synthesis of these devices are examined; these methods are based on a matrix representation of the structure of these devices, and a vector-matrix interpretation of certain aspects of Boolean algebra. Particular consideration is given to the theory of elementary matrix circuits, methods for the minimization of Boolean functions, the synthesis of programmable logic matrices, multilevel combinational networks, and the development of automata with memory.

  6. Subminiature deflection circuit operates integrated sweep circuits in TV camera

    NASA Technical Reports Server (NTRS)

    Schaff, F. L.

    1967-01-01

    Small magnetic sweep deflection circuits operate a hand-held lunar television camera. They convert timing signals from the synchronizer into waveforms that provide a raster on the vidicon target. Raster size remains constant and linear during wide voltage and temperature fluctuations.

  7. Realism test of a topography driven conceptual model (FLEX-Topo) in nested catchments of the Heihe River Basins, China

    NASA Astrophysics Data System (ADS)

    Gao, H.; Savenije, H.; Hrachowitz, M.; Fenicia, F.; Gharari, S.

    2013-12-01

    Although elevation data are globally available and many models do take topographical information into account, here it is demonstrated that topography is still an under-exploiting source of information in hydrological models . Based on the recently proposed modelling approach (FLEX-Topo) a semi-distributed topographic driven conceptual model (FLEXT), has been developed and tested in two nested catchments of the Heihe river basin. The model uses four topographical properties (i.e. Height Above the Nearest Drainage (HAND), absolute elevation, slope and aspect) to make a hydrological landscape classification which correspond with the dominant rainfall-runoff processes of these landscapes, to which a conceptual model structure is attributed. To analyses the additional information provided by the landscape classification, the performance of the FLEXT model is compared to a completely lumped hydrological models (FLEXL) and a semi-distributed model (FLEXD). All models have been calibrated and validated at the catchment outlet. Additionally, the models were evaluated in two nested sub-catchments. FLEXT performs substantially better than the other two models especially in the two nested sub-catchments during validation. It is especially better equipped to represent rainfall-runoff events during the dry season, which supports the following hypotheses: (1) topography can be used to distinguish different landscape elements with different hydrological function; (2) the model structure of the FLEXT is much better equipped to represent hydrological signatures than a lumped or semi-distributed model, and hence has a more realistic model structure and parameterization. The hydrograph components of the calibration(a), split-sample validation(b) and nested sub-catchments validation(c,d), of the FLEXT model

  8. Comparison of the Thickness of Pulley and Flexor Tendon Between in Neutral and in Flexed Positions of Trigger Finger

    PubMed Central

    Sato, Junko; Ishii, Yoshinori; Noguchi, Hideo

    2016-01-01

    Objective: This study aims to compare the morphology of the A1 pulley and flexor tendons in idiopathic trigger finger of digits other than the thumb between in neutral position and in the position with the interphalangeal joints full flexed and with the metacarpophalangeal (MP) joint 0° extended (hook grip position). Method: A total of 48 affected digits and 48 contralateral normal digits from 48 patients who initially diagnosed with idiopathic trigger finger were studied sonographically. Sonographic analysis was focused on the A1 pulley and flexor tendons at the level of the MP joint in the transverse plane. We measured the anterior-posterior thickness of A1 pulley and the sum of the flexor digitorum superficialis and profundus tendons, and also measured the maximum radialulnar width of the flexor tendon in neutral and hook grip positions, respectively. Each measurement was compared between in neutral and in hook grip positions, and also between the affected and contralateral normal digits in each position. Results: In all the digits, the anterior-posterior thickness of flexor tendons significantly increased in hook grip position as compared with in neutral position, whereas radial-ulnar width significantly decreased. Both the A1 pulley and flexor tendons were thicker in the affected digits as compared with contralateral normal digits. Conclusion: The thickness of flexor tendons was significantly increased anteroposteriorly in hook grip position as compared with in neutral position. In trigger finger, A1 pulley and flexor tendon were thickened, and mismatch between the volume of the flexor tendon sheath and the tendons, especially in anterior-posterior direction, might be a cause of repetitive triggering. PMID:27099639

  9. A Flex-Model for long-term assessment of community-residing older adults following disasters.

    PubMed

    Rosenkoetter, Marlene M; McDonough, JoEllen; McCall, Amber; Smith, Deborah; Looney, Stephen

    2015-01-01

    For the rapidly growing older adult population, disaster consequences are frequently life disruptive and even life threatening. By 2050, it is estimated that the global older adult population will reach 22 percent of the total. With declining health, this population poses a particular risk needing to be addressed in emergency preparedness and disaster recovery. The purpose of this article is to describe a Flex-Model (F-M) for the long-term assessment of older adults following a disaster. An F-M is a series of three-dimensional representations of an archetype with flexible components, both linear and parallel, that can be adapted to situations, time, place, and needs. The model incorporates the Life Patterns Model and provides a template that can be adjusted to meet the needs of a local community, healthcare providers, and emergency management officials, regardless of the country or region, during the months after a disaster. The focus is on changes resulting from the disaster including roles, relationships, support systems, use of time, self-esteem, and life structure. Following a baseline assessment, each of these life patterns is assessed through the model with options for interventions over time. A pilot study was conducted in Georgia to gain information that would be helpful in developing a more specific assessment tool following a severe winter storm. While this is a local study, the findings can nevertheless be used to refine and focus the F-M for future implementation. Results indicated that older adults used high-risk heating and lighting sources and many were totally responsible for their own welfare. Findings have implications for emergency preparedness and long-term recovery. PMID:26537697

  10. Fast Langmuir probe sweeping circuit

    SciTech Connect

    Milnes, K.A.; Ehlers, K.W.; Leung, K.N.; Owren, H.M.; Williams, M.D.

    1980-06-01

    An inexpensive, simple, and fast Langmuir probe sweeping circuit is presented. This sweeper completes a probe trace in 1.4 ms and has a maximum probe current capability of 5 A. It is suitable for pulsemode plasma operation with density greater than 10/sup 12/ ions/cm/sup 3/.

  11. Advanced Imaging of Elementary Circuits

    ERIC Educational Resources Information Center

    Baird, William H.; Richards, Caleb; Godbole, Pranav

    2012-01-01

    Students commonly find the second semester of introductory physics to be more challenging than the first, probably due to the mechanical intuition we acquire just by moving around. For most students, there is no similar comfort with electricity or magnetism. In an effort to combat this confusion, we decided to examine simple electric circuits with…

  12. Multiplier Architecture for Coding Circuits

    NASA Technical Reports Server (NTRS)

    Wang, C. C.; Truong, T. K.; Shao, H. M.; Deutsch, L. J.

    1986-01-01

    Multipliers based on new algorithm for Galois-field (GF) arithmetic regular and expandable. Pipeline structures used for computing both multiplications and inverses. Designs suitable for implementation in very-large-scale integrated (VLSI) circuits. This general type of inverter and multiplier architecture especially useful in performing finite-field arithmetic of Reed-Solomon error-correcting codes and of some cryptographic algorithms.

  13. No-warp potted circuits

    NASA Technical Reports Server (NTRS)

    Robinson, W. W.

    1979-01-01

    Sponge inserts compensate for potting-compound expansion and relieve thermal stresses on circuit boards. Technique quality of production runs on PC boards intended for applications in environments less severe than those for aerospace equipment. Pads reduce weight of modules because they weigh far less than potting compound they displace.

  14. Low-frequency attenuator circuit

    NASA Technical Reports Server (NTRS)

    Cash, W. H., Jr.; Polyhemus, J. T.

    1979-01-01

    Circuit uses only single operational amplifier and few passive components to remove background noise from miniature "wristwatch" pulse detector. It can be applied to other systems where background noise is slowly varying, such as ultrasonics, strain-gage sensors, and accelerometers.

  15. Integrated Circuit Stellar Magnitude Simulator

    ERIC Educational Resources Information Center

    Blackburn, James A.

    1978-01-01

    Describes an electronic circuit which can be used to demonstrate the stellar magnitude scale. Six rectangular light-emitting diodes with independently adjustable duty cycles represent stars of magnitudes 1 through 6. Experimentally verifies the logarithmic response of the eye. (Author/GA)

  16. MOS integrated circuit fault modeling

    NASA Technical Reports Server (NTRS)

    Sievers, M.

    1985-01-01

    Three digital simulation techniques for MOS integrated circuit faults were examined. These techniques embody a hierarchy of complexity bracketing the range of simulation levels. The digital approaches are: transistor-level, connector-switch-attenuator level, and gate level. The advantages and disadvantages are discussed. Failure characteristics are also described.

  17. Fabric circuits and method of manufacturing fabric circuits

    NASA Technical Reports Server (NTRS)

    Chu, Andrew W. (Inventor); Dobbins, Justin A. (Inventor); Scully, Robert C. (Inventor); Trevino, Robert C. (Inventor); Lin, Greg Y. (Inventor); Fink, Patrick W. (Inventor)

    2011-01-01

    A flexible, fabric-based circuit comprises a non-conductive flexible layer of fabric and a conductive flexible layer of fabric adjacent thereto. A non-conductive thread, an adhesive, and/or other means may be used for attaching the conductive layer to the non-conductive layer. In some embodiments, the layers are attached by a computer-driven embroidery machine at pre-determined portions or locations in accordance with a pre-determined attachment layout before automated cutting. In some other embodiments, an automated milling machine or a computer-driven laser using a pre-designed circuit trace as a template cuts the conductive layer so as to separate an undesired portion of the conductive layer from a desired portion of the conductive layer. Additional layers of conductive fabric may be attached in some embodiments to form a multi-layer construct.

  18. Analog Nonvolatile Computer Memory Circuits

    NASA Technical Reports Server (NTRS)

    MacLeod, Todd

    2007-01-01

    In nonvolatile random-access memory (RAM) circuits of a proposed type, digital data would be stored in analog form in ferroelectric field-effect transistors (FFETs). This type of memory circuit would offer advantages over prior volatile and nonvolatile types: In a conventional complementary metal oxide/semiconductor static RAM, six transistors must be used to store one bit, and storage is volatile in that data are lost when power is turned off. In a conventional dynamic RAM, three transistors must be used to store one bit, and the stored bit must be refreshed every few milliseconds. In contrast, in a RAM according to the proposal, data would be retained when power was turned off, each memory cell would contain only two FFETs, and the cell could store multiple bits (the exact number of bits depending on the specific design). Conventional flash memory circuits afford nonvolatile storage, but they operate at reading and writing times of the order of thousands of conventional computer memory reading and writing times and, hence, are suitable for use only as off-line storage devices. In addition, flash memories cease to function after limited numbers of writing cycles. The proposed memory circuits would not be subject to either of these limitations. Prior developmental nonvolatile ferroelectric memories are limited to one bit per cell, whereas, as stated above, the proposed memories would not be so limited. The design of a memory circuit according to the proposal must reflect the fact that FFET storage is only partly nonvolatile, in that the signal stored in an FFET decays gradually over time. (Retention times of some advanced FFETs exceed ten years.) Instead of storing a single bit of data as either a positively or negatively saturated state in a ferroelectric device, each memory cell according to the proposal would store two values. The two FFETs in each cell would be denoted the storage FFET and the control FFET. The storage FFET would store an analog signal value

  19. Terahertz backward wave oscillator circuits

    NASA Astrophysics Data System (ADS)

    Oviedo Vela, Guillermo Antonio

    This work focuses on increasing the electric field mode-electron beam interaction in terahertz backward-wave oscillators through increasing the interaction impedance of the slow wave circuit. In a backward wave oscillator (BWO) or a traveling wave tube (TWT), the electric field traveling in the waveguide interacts with an electron beam grazing or piercing the electric field of a slow wave circuit and transfers energy from the beam to the circuit mode. The mechanism of this interaction is analyzed and the traditional model is adapted to provide one that is scalable to terahertz frequencies. The efficiency of the BWO can be enhanced by improving the interaction between the beam and the circuit modes, utilizing beam sources with greater current densities and using larger magnetic fields. This work presents the results on the modeling, fabrication and performance of the mode-piercing and mode-grazing slow wave circuits studied. Meandering folded waveguides and interdigital lines were modeled to evaluate their interaction impedance and electron beam requirements at terahertz frequencies. The models were verified against published results. Because of their low interaction impedance, terahertz meandering waveguides would need to be excited with large current density electron beams which in turn would require large magnets for their control. Interdigital lines were found to be the slow-wave circuit of choice in this work because their high interaction impedance and their ability to operate with low voltage, and low current density electron beams. Finite element numerical calculations were used to design, optimize and scale a terahertz free interdigital line (FIDL) circuit. The designed free interdigital line was fabricated using microfabrication technologies. Characterization of a free interdigital line (FIDL) circuit was performed in a tube body with a dispenser cathode and a three-anode Pierce gun. The FIDL measured output was compared with the calculated result and its

  20. Driver circuit for solid state light sources

    DOEpatents

    Palmer, Fred; Denvir, Kerry; Allen, Steven

    2016-02-16

    A driver circuit for a light source including one or more solid state light sources, a luminaire including the same, and a method of so driving the solid state light sources are provided. The driver circuit includes a rectifier circuit that receives an alternating current (AC) input voltage and provides a rectified AC voltage. The driver circuit also includes a switching converter circuit coupled to the light source. The switching converter circuit provides a direct current (DC) output to the light source in response to the rectified AC voltage. The driver circuit also includes a mixing circuit, coupled to the light source, to switch current through at least one solid state light source of the light source in response to each of a plurality of consecutive half-waves of the rectified AC voltage.

  1. 30 CFR 56.6403 - Branch circuits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Electric Blasting § 56.6403 Branch circuits. (a) If electric blasting includes the use of branch circuits,...

  2. 30 CFR 56.6403 - Branch circuits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Electric Blasting § 56.6403 Branch circuits. (a) If electric blasting includes the use of branch circuits,...

  3. 30 CFR 56.6403 - Branch circuits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Electric Blasting § 56.6403 Branch circuits. (a) If electric blasting includes the use of branch circuits,...

  4. 30 CFR 56.6403 - Branch circuits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Electric Blasting § 56.6403 Branch circuits. (a) If electric blasting includes the use of branch circuits,...

  5. 30 CFR 56.6403 - Branch circuits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Explosives Electric Blasting § 56.6403 Branch circuits. (a) If electric blasting includes the use of branch circuits,...

  6. Auxiliary circuit enables automatic monitoring of EKG'S

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Auxiliary circuits allow direct, automatic monitoring of electrocardiograms by digital computers. One noiseless square-wave output signal for each trigger pulse from an electrocardiogram preamplifier is produced. The circuit also permits automatic processing of cardiovascular data from analog tapes.

  7. Plug-in integrated/hybrid circuit

    NASA Technical Reports Server (NTRS)

    Stringer, E. J.

    1974-01-01

    Hybrid circuitry can be installed into standard round bayonet connectors, to eliminate wiring from connector to circuit. Circuits can be connected directly into either section of connector pair, eliminating need for hard wiring to that section.

  8. Post regulation circuit with energy storage

    DOEpatents

    Ball, Don G.; Birx, Daniel L.; Cook, Edward G.

    1992-01-01

    A charge regulation circuit provides regulation of an unregulated voltage supply and provides energy storage. The charge regulation circuit according to the present invention provides energy storage without unnecessary dissipation of energy through a resistor as in prior art approaches.

  9. Performance optimization of digital VLSI circuits

    SciTech Connect

    Marple, D.P.

    1987-01-01

    Designers of digital VLSI circuits have virtually no computer tools available for the optimization of circuit performance. Instead, a designer relies extensively on circuit-analysis tools, such as circuit simulation (SPICE) and/or critical-delay-path analysis. A circuit-analysis approach to digital design is very labor-intensive and seldom produces a circuit with optimum area/delay or power/delay trade off. The goal of this research is to provide a synthesis approach to the design of digital circuits by finding the sizes of transistors that optimize circuits by finding the sizes of transistors that optimize circuit performance (delay, area, power). Solutions are found that are optimum for all possible delay paths of a given circuit and not for just a single path. The approach of this research is to formulate the problem of area/delay or power/delay optimization as a nonlinear program. Conditions for optimality are then established using graph theory and Kuhn-Tucker conditions. Finally, the use of augmented-Lagrangian and projected-Lagrangian algorithms are reviewed for the solution of the nonlinear programs. Two computer programs, PLATO and COP, were developed by the author to optimize CMOS PLA's (PLATO) and general CMOS circuits (COP). These tools provably find the globally optimum transistor sizes for a given circuit. Results are presented for PLA's and small- to medium-sized cells.

  10. 49 CFR 236.726 - Circuit, track.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Circuit, track. 236.726 Section 236.726 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, track. An electrical circuit of which the rails of the track form a part....

  11. 49 CFR 236.726 - Circuit, track.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Circuit, track. 236.726 Section 236.726 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, track. An electrical circuit of which the rails of the track form a part....

  12. 30 CFR 75.1323 - Blasting circuits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) Blasting circuits shall be protected from sources of stray electric current. (b) Detonators made by different manufacturers shall not be combined in the same blasting circuit. (c) Detonator leg wires shall be shunted until connected into the blasting circuit. (d) Blasting cables shall be— (1) Well...

  13. 49 CFR 236.726 - Circuit, track.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Circuit, track. 236.726 Section 236.726 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, track. An electrical circuit of which the rails of the track form a part....

  14. 30 CFR 75.1323 - Blasting circuits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) Blasting circuits shall be protected from sources of stray electric current. (b) Detonators made by different manufacturers shall not be combined in the same blasting circuit. (c) Detonator leg wires shall be shunted until connected into the blasting circuit. (d) Blasting cables shall be— (1) Well...

  15. 49 CFR 236.721 - Circuit, control.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Circuit, control. An electrical circuit between a source of electric energy and a device which it operates. ... 49 Transportation 4 2012-10-01 2012-10-01 false Circuit, control. 236.721 Section 236.721 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD...

  16. 49 CFR 236.721 - Circuit, control.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Circuit, control. An electrical circuit between a source of electric energy and a device which it operates. ... 49 Transportation 4 2014-10-01 2014-10-01 false Circuit, control. 236.721 Section 236.721 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD...

  17. 49 CFR 236.726 - Circuit, track.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Circuit, track. 236.726 Section 236.726 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, track. An electrical circuit of which the rails of the track form a part....

  18. 49 CFR 236.726 - Circuit, track.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, track. 236.726 Section 236.726 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, track. An electrical circuit of which the rails of the track form a part....

  19. 49 CFR 236.721 - Circuit, control.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Circuit, control. An electrical circuit between a source of electric energy and a device which it operates. ... 49 Transportation 4 2013-10-01 2013-10-01 false Circuit, control. 236.721 Section 236.721 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD...

  20. The dc power circuits: A compilation

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A compilation of reports concerning power circuits is presented for the dissemination of aerospace information to the general public as part of the NASA Technology Utilization Program. The descriptions for the electronic circuits are grouped as follows: dc power supplies, power converters, current-voltage power supply regulators, overload protection circuits, and dc constant current power supplies.

  1. New Logic Circuit with DC Parametric Excitation

    NASA Astrophysics Data System (ADS)

    Sugahara, Masanori; Kaneda, Hisayoshi

    1982-12-01

    It is shown that dc parametric excitation is possible in a circuit named JUDO, which is composed of two resistively-connected Josephson junctions. Simulation study proves that the circuit has large gain and properties suitable for the construction of small, high-speed logic circuits.

  2. Overvoltage control circuit for a reserve battery

    SciTech Connect

    Eppley, W.J.; Pertuch, W.T.; Tierney, B.C.

    1989-09-26

    This patent describes a selectively activatable reserve battery overvoltage control circuit. It comprises: a current limiting resistor; a thermal-lag circuit interrupter connected in series with the resistor; and circuit means connecting the series connection of the resistor and the interrupter across the reserve battery.

  3. 49 CFR 236.719 - Circuit, acknowledgment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, acknowledgment. 236.719 Section 236.719 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Circuit, acknowledgment. A circuit consisting of wire or other conducting material installed between...

  4. 49 CFR 234.203 - Control circuits.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Control circuits. 234.203 Section 234.203... EMERGENCY NOTIFICATION SYSTEMS Maintenance, Inspection, and Testing Maintenance Standards § 234.203 Control circuits. All control circuits that affect the safe operation of a highway-rail grade crossing...

  5. 49 CFR 234.203 - Control circuits.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Control circuits. 234.203 Section 234.203... EMERGENCY NOTIFICATION SYSTEMS Maintenance, Inspection, and Testing Maintenance Standards § 234.203 Control circuits. All control circuits that affect the safe operation of a highway-rail grade crossing...

  6. 49 CFR 234.203 - Control circuits.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Control circuits. 234.203 Section 234.203... EMERGENCY NOTIFICATION SYSTEMS Maintenance, Inspection, and Testing Maintenance Standards § 234.203 Control circuits. All control circuits that affect the safe operation of a highway-rail grade crossing...

  7. Electronic test and calibration circuits, a compilation

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A wide variety of simple test calibration circuits are compiled for the engineer and laboratory technician. The majority of circuits were found inexpensive to assemble. Testing electronic devices and components, instrument and system test, calibration and reference circuits, and simple test procedures are presented.

  8. 30 CFR 75.1323 - Blasting circuits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Blasting circuits. 75.1323 Section 75.1323 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1323 Blasting circuits. (a) Blasting circuits shall be protected...

  9. 30 CFR 75.1323 - Blasting circuits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Blasting circuits. 75.1323 Section 75.1323 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1323 Blasting circuits. (a) Blasting circuits shall be protected...

  10. 49 CFR 234.203 - Control circuits.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Control circuits. 234.203 Section 234.203 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., Inspection, and Testing Maintenance Standards § 234.203 Control circuits. All control circuits that...

  11. 49 CFR 236.721 - Circuit, control.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, control. 236.721 Section 236.721..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.721 Circuit, control. An electrical circuit between a source of electric energy and a device which it operates....

  12. 49 CFR 236.721 - Circuit, control.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Circuit, control. 236.721 Section 236.721..., MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Definitions § 236.721 Circuit, control. An electrical circuit between a source of electric energy and a device which it operates....

  13. 49 CFR 234.203 - Control circuits.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Control circuits. 234.203 Section 234.203 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION..., Inspection, and Testing Maintenance Standards § 234.203 Control circuits. All control circuits that...

  14. Removing Bonded Integrated Circuits From Boards

    NASA Technical Reports Server (NTRS)

    Rice, John T.

    1989-01-01

    Small resistance heater makes it easier, faster, and cheaper to remove integrated circuit from hybrid-circuit board, package, or other substrate for rework. Heater, located directly in polymeric bond interface or on substrate under integrated-circuit chip, energized when necessary to remove chip. Heat generated softens adhesive or solder that bonds chip to substrate. Chip then lifted easily from substrate.

  15. Simple photometer circuits using modular electronic components

    NASA Technical Reports Server (NTRS)

    Wampler, J. E.

    1975-01-01

    Operational and peak holding amplifiers are discussed as useful circuits for bioluminescence assays. Circuit diagrams are provided. While analog methods can give a good integration on short time scales, digital methods were found best for long term integration in bioluminescence assays. Power supplies, a general photometer circuit with ratio capability, and variations in the basic photometer design are also considered.

  16. Ionization tube simmer current circuit

    DOEpatents

    Steinkraus, Jr., Robert F.

    1994-01-01

    A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current.

  17. Ionization tube simmer current circuit

    DOEpatents

    Steinkraus, R.F. Jr.

    1994-12-13

    A highly efficient flash lamp simmer current circuit utilizes a fifty percent duty cycle square wave pulse generator to pass a current over a current limiting inductor to a full wave rectifier. The DC output of the rectifier is then passed over a voltage smoothing capacitor through a reverse current blocking diode to a flash lamp tube to sustain ionization in the tube between discharges via a small simmer current. An alternate embodiment of the circuit combines the pulse generator and inductor in the form of an FET off line square wave generator with an impedance limited step up output transformer which is then applied to the full wave rectifier as before to yield a similar simmer current. 6 figures.

  18. Pattern Transformation with DNA Circuits

    PubMed Central

    Chirieleison, Steven M.; Allen, Peter B.; Simpson, Zack B.; Ellington, Andrew D.; Chen, Xi

    2014-01-01

    Readily programmable chemical networks are important tools as the scope of chemistry expands from individual molecules to larger molecular systems. While many complex systems have been constructed using conventional organic and inorganic chemistry, the programmability of biological molecules such as nucleic acids allows for precise, high-throughput, and automated design, as well as simple, rapid, and robust implementation. Here we show that systematic and quantitative control over the diffusivity and reactivity of DNA molecules yields highly programmable chemical reaction networks (CRNs) that execute at the macroscale. In particular, we design and implement non-enzymatic DNA circuits capable of performing pattern transformation algorithms such as edge detection. We also show that it is possible to fine-tune and multiplex such circuits. We believe these strategies will provide programmable platforms for prototyping CRNs, for discovering bottom-up construction principles, and for generating patterns in materials. PMID:24256862

  19. Planar Multilayer Circuit Quantum Electrodynamics

    NASA Astrophysics Data System (ADS)

    Minev, Z. K.; Serniak, K.; Pop, I. M.; Leghtas, Z.; Sliwa, K.; Hatridge, M.; Frunzio, L.; Schoelkopf, R. J.; Devoret, M. H.

    2016-04-01

    Experimental quantum information processing with superconducting circuits is rapidly advancing, driven by innovation in two classes of devices, one involving planar microfabricated (2D) resonators, and the other involving machined three-dimensional (3D) cavities. We demonstrate that circuit quantum electrodynamics can be implemented in a multilayer superconducting structure that combines 2D and 3D advantages. We employ standard microfabrication techniques to pattern each layer, and rely on a vacuum gap between the layers to store the electromagnetic energy. Planar qubits are lithographically defined as an aperture in a conducting boundary of the resonators. We demonstrate the aperture concept by implementing an integrated, two-cavity-mode, one-transmon-qubit system.

  20. Overpulse railgun energy recovery circuit

    SciTech Connect

    Honig, E.M.

    1989-12-12

    This patent describes an overpulse railgun energy recovery circuit for propelling a projectile along a railgun. The overpulse rail gun energy recovery circuit comprising: a railgun having an effective inductance, the railgun having a breach end, a pair of parallel rails, and a muzzle end; source inductor for storing current connected across the pair of parallel rails of the railgun at the breech end thereof; means for initially charging the source inductor to an initial current for storage; switching means connected across the source inductor with a closed position for shorting across the source inductor and an open position for enabling current flow into the effective inductance of the breech end towards the muzzle end of the railgun; a muzzle switch connected across the pair of parallel rails of the railgun at the muzzle end thereof; and transfer capacitive means.

  1. Delta connected resonant snubber circuit

    DOEpatents

    Lai, J.S.; Peng, F.Z.; Young, R.W. Sr.; Ott, G.W. Jr.

    1998-01-20

    A delta connected, resonant snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the dc supply voltage through the main inverter switches and the auxiliary switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter. 36 figs.

  2. Delta connected resonant snubber circuit

    DOEpatents

    Lai, Jih-Sheng; Peng, Fang Zheng; Young, Sr., Robert W.; Ott, Jr., George W.

    1998-01-01

    A delta connected, resonant snubber-based, soft switching, inverter circuit achieves lossless switching during dc-to-ac power conversion and power conditioning with minimum component count and size. Current is supplied to the resonant snubber branches solely by the dc supply voltage through the main inverter switches and the auxiliary switches. Component count and size are reduced by use of a single semiconductor switch in the resonant snubber branches. Component count is also reduced by maximizing the use of stray capacitances of the main switches as parallel resonant capacitors. Resonance charging and discharging of the parallel capacitances allows lossless, zero voltage switching. In one embodiment, circuit component size and count are minimized while achieving lossless, zero voltage switching within a three-phase inverter.

  3. Delay locked loop integrated circuit.

    SciTech Connect

    Brocato, Robert Wesley

    2007-10-01

    This report gives a description of the development of a Delay Locked Loop (DLL) integrated circuit (IC). The DLL was developed and tested as a stand-alone IC test chip to be integrated into a larger application specific integrated circuit (ASIC), the Quadrature Digital Waveform Synthesizer (QDWS). The purpose of the DLL is to provide a digitally programmable delay to enable synchronization between an internal system clock and external peripherals with unknown clock skew. The DLL was designed and fabricated in the IBM 8RF process, a 0.13 {micro}m CMOS process. It was designed to operate with a 300MHz clock and has been tested up to 500MHz.

  4. Monolithic readout circuits for RHIC

    SciTech Connect

    O`Connor, P.; Harder, J.

    1991-12-31

    Several CMOS ASICs have been developed for a proposed RHIC experiment. This paper discusses why ASIC implementation was chosen for certain functions, circuit specifications and the design techniques used to meet them, and results of simulations and early prototypes. By working closely together from an early stage in the planning process, in-house ASIC designers and detector and data acquisition experimenters can achieve optimal use of this important technology.

  5. Photoconductive circuit element pulse generator

    DOEpatents

    Rauscher, Christen

    1989-01-01

    A pulse generator for characterizing semiconductor devices at millimeter wavelength frequencies where a photoconductive circuit element (PCE) is biased by a direct current voltage source and produces short electrical pulses when excited into conductance by short laser light pulses. The electrical pulses are electronically conditioned to improve the frequency related amplitude characteristics of the pulses which thereafter propagate along a transmission line to a device under test.

  6. Counterpulse railgun energy recovery circuit

    DOEpatents

    Honig, Emanuel M.

    1986-01-01

    In an electromagnetic launcher such as a railgun for propelling a projectile at high velocity, a counterpulse energy recovery circuit is employed to transfer stored inductive energy from a source inductor to the railgun inductance to propel the projectile down the railgun. Switching circuitry and an energy transfer capacitor are used to switch the energy back to the source inductor in readiness for a repetitive projectile propelling cycle.

  7. Overpulse railgun energy recovery circuit

    DOEpatents

    Honig, Emanuel M.

    1989-01-01

    In an electromagnetic launcher such as a railgun for propelling a projectile at high velocity, an overpulse energy recovery circuit is employed to transfer stored inductive energy from a source inductor to the railgun inductance to propel the projectile down the railgun. Switching circuitry and an energy transfer capacitor are used to switch the energy back to the source inductor in readiness for a repetitive projectile propelling cycle.

  8. Effects of High Octane Ethanol Blends on Four Legacy Flex-Fuel Vehicles, and a Turbocharged GDI Vehicle

    SciTech Connect

    Thomas, John F; West, Brian H; Huff, Shean P

    2015-03-01

    The U.S. Department of Energy (DOE) is supporting engine and vehicle research to investigate the potential of high-octane fuels to improve fuel economy. Ethanol has very high research octane number (RON) and heat of vaporization (HoV), properties that make it an excellent spark ignition engine fuel. The prospects of increasing both the ethanol content and the octane number of the gasoline pool has the potential to enable improved fuel economy in future vehicles with downsized, downsped engines. This report describes a small study to explore the potential performance benefits of high octane ethanol blends in the legacy fleet. There are over 17 million flex-fuel vehicles (FFVs) on the road today in the United States, vehicles capable of using any fuel from E0 to E85. If a future high-octane blend for dedicated vehicles is on the horizon, the nation is faced with the classic chicken-and-egg dilemma. If today’s FFVs can see a performance advantage with a high octane ethanol blend such as E25 or E30, then perhaps consumer demand for this fuel can serve as a bridge to future dedicated vehicles. Experiments were performed with four FFVs using a 10% ethanol fuel (E10) with 88 pump octane, and a market gasoline blended with ethanol to make a 30% by volume ethanol fuel (E30) with 94 pump octane. The research octane numbers were 92.4 for the E10 fuel and 100.7 for the E30 fuel. Two vehicles had gasoline direct injected (GDI) engines, and two featured port fuel injection (PFI). Significant wide open throttle (WOT) performance improvements were measured for three of the four FFVs, with one vehicle showing no change. Additionally, a conventional (non-FFV) vehicle with a small turbocharged direct-injected engine was tested with a regular grade of gasoline with no ethanol (E0) and a splash blend of this same fuel with 15% ethanol by volume (E15). RON was increased from 90.7 for the E0 to 97.8 for the E15 blend. Significant wide open throttle and thermal efficiency performance

  9. China Flexes Linguistic Muscles

    ERIC Educational Resources Information Center

    Robelen, Erik W.

    2010-01-01

    With China's growing power and influence on the global stage, efforts are burgeoning to promote teaching the official Chinese language in U.S. schools. And while those activities are getting help from a variety of sources--including the U.S. government--one key player taking an increased role is the Chinese government itself. Just this year, the…

  10. FLEX Test Point Video

    NASA Video Gallery

    Test #1 - Droplet diameter of 4 mm, with no support fiber. Droplet deployment was successful with a brief burn before radiative extinction. An afterglow from condensing vapor cloud and scattered ba...

  11. FlexTech{trademark}

    SciTech Connect

    Wilhelm, B.

    1996-12-31

    Information is presented on a 110 MWe atmospheric CFB located in the Czech Republic firing brown coal. The following topics are discussed: fuel analysis; boiler design parameters; CFB fluidizing nozzle; and project time schedule. Information is also given on a 200 MWe atmospheric CFB located in the Republic of Korea firing Korean anthracite. Data are presented on fuel specifications; predicted performance; and engineering and construction schedule.

  12. Digital model of a vacuum circuit breaker for the analysis of switching waveforms in electrical circuits

    NASA Astrophysics Data System (ADS)

    Budzisz, Joanna; Wróblewski, Zbigniew

    2016-03-01

    The article presents a method of modelling a vaccum circuit breaker in the ATP/EMTP package, the results of the verification of the correctness of the developed digital circuit breaker model operation and its practical usefulness for analysis of overvoltages and overcurrents occurring in commutated capacitive electrical circuits and also examples of digital simulations of overvoltages and overcurrents in selected electrical circuits.

  13. Electrical circuit for data reduction

    SciTech Connect

    Kronberg, J.W.

    1991-12-31

    This invention is comprised of an electrical circuit for determining characteristic voltages, such as maximum, minimum, average and root mean squared voltages, of a time-varying electrical signal. The circuit comprises a positive and a negative peak detector that feed the positive and negative voltage peaks detected in each of a series of time intervals into a solid-state multiplexer controlled by a process controller. The time intervals are generated by the process controller in combination with a clocking, circuit. The multiplexer applies the positive and negative peak voltages to a set of four capacitors, apply the positive peak to one capacitor during one interval and then the negative peak to that capacitor in a subsequent interval so that each capacitor is alternatingly accumulating a positive peak then a negative peak to obviate the need for resetting each capacitor. After the positive peak voltage is applied to one capacitor, the connection is switched during the next interval for reading the negative peak voltage, then switched again for applying, a negative peak voltage, then switched once more for reading the negative peak voltage, the multiplexer serving, as a solid state commutator for switching the electrical connection. Alternatively, peak maximum and minimum voltage detectors may be replaced with circuitry designed to obtain the additional characteristic voltages desired in each interval.

  14. CONTROL AND FAULT DETECTOR CIRCUIT

    DOEpatents

    Winningstad, C.N.

    1958-04-01

    A power control and fault detectcr circuit for a radiofrequency system is described. The operation of the circuit controls the power output of a radio- frequency power supply to automatically start the flow of energizing power to the radio-frequency power supply and to gradually increase the power to a predetermined level which is below the point where destruction occurs upon the happening of a fault. If the radio-frequency power supply output fails to increase during such period, the control does not further increase the power. On the other hand, if the output of the radio-frequency power supply properly increases, then the control continues to increase the power to a maximum value. After the maximumn value of radio-frequency output has been achieved. the control is responsive to a ''fault,'' such as a short circuit in the radio-frequency system being driven, so that the flow of power is interrupted for an interval before the cycle is repeated.

  15. Additive manufacturing of hybrid circuits

    DOE PAGESBeta

    Bell, Nelson S.; Sarobol, Pylin; Cook, Adam; Clem, Paul G.; Keicher, David M.; Hirschfeld, Deidre; Hall, Aaron Christopher

    2016-03-26

    There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects.more » Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. As a result, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes.« less

  16. The global electrical circuit: A review

    NASA Astrophysics Data System (ADS)

    Williams, Earle R.

    2009-02-01

    Research topics on the global electrical circuit are addressed that have received attention in recent years. These topics include the diurnal variation of the global circuit, surface measurements of electric field at high latitude, the annual variation, the semiannual variation, the role of lightning as a source for the global circuit, the electrical contribution of mesoscale convective systems, the possible effect of thunderstorms on the E and F regions of the ionosphere, the evidence for a global circuit impact from nuclear weapons tests, the controversy over long-term variations, the response to climate change, and finally the impact of the global circuit on climate.

  17. Method of determining the open circuit voltage of a battery in a closed circuit

    DOEpatents

    Brown, William E.

    1980-01-01

    The open circuit voltage of a battery which is connected in a closed circuit is determined without breaking the circuit or causing voltage upsets therein. The closed circuit voltage across the battery and the current flowing through it are determined under normal load and then a fractional change is made in the load and the new current and voltage values determined. The open circuit voltage is then calculated, according to known principles, from the two sets of values.

  18. Method and Circuit for Injecting a Precise Amount of Charge onto a Circuit Node

    NASA Technical Reports Server (NTRS)

    Hancock, Bruce R. (Inventor)

    2016-01-01

    A method and circuit for injecting charge into a circuit node, comprising (a) resetting a capacitor's voltage through a first transistor; (b) after the resetting, pre-charging the capacitor through the first transistor; and (c) after the pre-charging, further charging the capacitor through a second transistor, wherein the second transistor is connected between the capacitor and a circuit node, and the further charging draws charge through the second transistor from the circuit node, thereby injecting charge into the circuit node.

  19. Faster Evolution of More Multifunctional Logic Circuits

    NASA Technical Reports Server (NTRS)

    Stoica, Adrian; Zebulum, Ricardo

    2005-01-01

    A modification in a method of automated evolutionary synthesis of voltage-controlled multifunctional logic circuits makes it possible to synthesize more circuits in less time. Prior to the modification, the computations for synthesizing a four-function logic circuit by this method took about 10 hours. Using the method as modified, it is possible to synthesize a six-function circuit in less than half an hour. The concepts of automated evolutionary synthesis and voltage-controlled multifunctional logic circuits were described in a number of prior NASA Tech Briefs articles. To recapitulate: A circuit is designed to perform one of several different logic functions, depending on the value of an applied control voltage. The circuit design is synthesized following an automated evolutionary approach that is so named because it is modeled partly after the repetitive trial-and-error process of biological evolution. In this process, random populations of integer strings that encode electronic circuits play a role analogous to that of chromosomes. An evolved circuit is tested by computational simulation (prior to testing in real hardware to verify a final design). Then, in a fitness-evaluation step, responses of the circuit are compared with specifications of target responses and circuits are ranked according to how close they come to satisfying specifications. The results of the evaluation provide guidance for refining designs through further iteration.

  20. Auto-programmable impulse neural circuits

    NASA Technical Reports Server (NTRS)

    Watula, D.; Meador, J.

    1990-01-01

    Impulse neural networks use pulse trains to communicate neuron activation levels. Impulse neural circuits emulate natural neurons at a more detailed level than that typically employed by contemporary neural network implementation methods. An impulse neural circuit which realizes short term memory dynamics is presented. The operation of that circuit is then characterized in terms of pulse frequency modulated signals. Both fixed and programmable synapse circuits for realizing long term memory are also described. The implementation of a simple and useful unsupervised learning law is then presented. The implementation of a differential Hebbian learning rule for a specific mean-frequency signal interpretation is shown to have a straightforward implementation using digital combinational logic with a variation of a previously developed programmable synapse circuit. This circuit is expected to be exploited for simple and straightforward implementation of future auto-adaptive neural circuits.

  1. Clinical Outcomes in Men and Women following Total Knee Arthroplasty with a High-Flex Knee: No Clinical Effect of Gender

    PubMed Central

    Nassif, Jeffrey M.; Pietrzak, William S.

    2015-01-01

    While it is generally recognized that anatomical differences exist between the male and female knee, the literature generally refutes the clinical need for gender-specific total knee prostheses. It has been found that standard, unisex knees perform as well, or better, in women than men. Recently, high-flex knees have become available that mechanically accommodate increased flexion yet no studies have directly compared the outcomes of these devices in men and women to see if gender-based differences exist. We retrospectively compared the performance of the high-flex Vanguard knee (Biomet, Warsaw, IN) in 716 male and 1,069 female knees. Kaplan-Meier survivorship was 98.5% at 5.6–5.7 years for both genders. After 2 years, mean improvements in Knee Society Knee and Function scores for men and women (50.9 versus 46.3; 26.5 versus 23.1) and corresponding SF-12 Mental and Physical scores (0.2 versus 2.2; 13.7 versus 12.2) were similar with differences not clinically relevant. Postoperative motion gains as a function of preoperative motion level were virtually identical in men and women. This further confirms the suitability of unisex total knee prostheses for both men and women. PMID:26451389

  2. PerFlexMEA: a thin microporous microelectrode array for in vitro cardiac electrophysiological studies on hetero-cellular bilayers with controlled gap junction communication.

    PubMed

    Mondal, A; Baker, B; Harvey, I R; Moreno, A P

    2015-05-01

    The new microelectrode array device presented is called PerFlexMEA and it enables controlled coupling between myocytes and nonmyocytes used in cardiovascular conduction studies. The device consists of an 8 μm thin parylene microporous membrane with a 4 × 5 microelectrode array patterned on one side. Myocytes and nonmyocytes can be plated on either side of the parylene membrane to create a tissue bilayer. The 3-3.5 μm diameter pores allow inter-layer dye and electrical coupling without transmembrane cell migration. Cell migration was found to vary with cell-type and micropore diameter. Pore density can be varied based on desired coupling ratio. The flexible parylene membrane is packaged between two rigid thermoplastic layers, such that the microelectrode array region is exposed, while the rest of the device remains insulated. The packaged PerFlexMEA fits in a 60 mm culture dish. Recording experiments are performed by simply plugging it into a commercially available multielectrode amplifier system. Recorded signals were processed and analysed using scripts generated in MATLAB. Our experimental results provide evidence of the reliability of this device, as conduction velocity was observed to decrease after inducing lateral hetero-cellular controlled coupling between myocytes and HeLa cells expressing connexin 43. PMID:25797476

  3. 46 CFR 28.365 - Overcurrent protection and switched circuits.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... a steering circuit, each circuit must be protected against both overload and short circuit. Each overcurrent device in a steering system power and control circuit must provide short circuit protection only... 46 Shipping 1 2012-10-01 2012-10-01 false Overcurrent protection and switched circuits....

  4. 46 CFR 28.365 - Overcurrent protection and switched circuits.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... a steering circuit, each circuit must be protected against both overload and short circuit. Each overcurrent device in a steering system power and control circuit must provide short circuit protection only... 46 Shipping 1 2010-10-01 2010-10-01 false Overcurrent protection and switched circuits....

  5. 46 CFR 28.365 - Overcurrent protection and switched circuits.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... a steering circuit, each circuit must be protected against both overload and short circuit. Each overcurrent device in a steering system power and control circuit must provide short circuit protection only... 46 Shipping 1 2013-10-01 2013-10-01 false Overcurrent protection and switched circuits....

  6. 46 CFR 28.365 - Overcurrent protection and switched circuits.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... a steering circuit, each circuit must be protected against both overload and short circuit. Each overcurrent device in a steering system power and control circuit must provide short circuit protection only... 46 Shipping 1 2014-10-01 2014-10-01 false Overcurrent protection and switched circuits....

  7. 46 CFR 28.365 - Overcurrent protection and switched circuits.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... a steering circuit, each circuit must be protected against both overload and short circuit. Each overcurrent device in a steering system power and control circuit must provide short circuit protection only... carrying capacity by a circuit breaker or fuse at the connection to the switchboard or distribution...

  8. Inductive storage pulse circuit device

    DOEpatents

    Parsons, William M.; Honig, Emanuel M.

    1984-01-01

    Inductive storage pulse circuit device which is capable of delivering a series of electrical pulses to a load in a sequential manner. Silicon controlled rectifiers as well as spark gap switches can be utilized in accordance with the present invention. A commutation switching array is utilized to produce a reverse current to turn-off the main opening switch. A commutation capacitor produces the reverse current and is initially charged to a predetermined voltage and subsequently charged in alternating directions by the inductive storage current.

  9. Circuit for Driving Piezoelectric Transducers

    NASA Technical Reports Server (NTRS)

    Randall, David P.; Chapsky, Jacob

    2009-01-01

    The figure schematically depicts an oscillator circuit for driving a piezoelectric transducer to excite vibrations in a mechanical structure. The circuit was designed and built to satisfy application-specific requirements to drive a selected one of 16 such transducers at a regulated amplitude and frequency chosen to optimize the amount of work performed by the transducer and to compensate for both (1) temporal variations of the resonance frequency and damping time of each transducer and (2) initially unknown differences among the resonance frequencies and damping times of different transducers. In other words, the circuit is designed to adjust itself to optimize the performance of whichever transducer is selected at any given time. The basic design concept may be adaptable to other applications that involve the use of piezoelectric transducers in ultrasonic cleaners and other apparatuses in which high-frequency mechanical drives are utilized. This circuit includes three resistor-capacitor networks that, together with the selected piezoelectric transducer, constitute a band-pass filter having a peak response at a frequency of about 2 kHz, which is approximately the resonance frequency of the piezoelectric transducers. Gain for generating oscillations is provided by a power hybrid operational amplifier (U1). A junction field-effect transistor (Q1) in combination with a resistor (R4) is used as a voltage-variable resistor to control the magnitude of the oscillation. The voltage-variable resistor is part of a feedback control loop: Part of the output of the oscillator is rectified and filtered for use as a slow negative feedback to the gate of Q1 to keep the output amplitude constant. The response of this control loop is much slower than 2 kHz and, therefore, does not introduce significant distortion of the oscillator output, which is a fairly clean sine wave. The positive AC feedback needed to sustain oscillations is derived from sampling the current through the

  10. Circuit considerations for repetitive railguns

    SciTech Connect

    Honih, E.M.

    1986-01-01

    Railgun electromagnetic launchers have significant military and scientific potential. They provide direct conversion of electrical energy to projectile kinetic energy, and they offer the hope of achieving projectile velocities greatly exceeding the limits of conventional guns. With over 10 km/sec already demonstrated, railguns are attracting attention for tactical and strategic weapons systems and for scientific equation-of-state research. The full utilization of railguns will require significant improvements in every aspect of system design - projectile, barrel, and power source - to achieve operation on a large scale. This paper will review fundamental aspects of railguns, with emphasis on circuit considerations and repetitive operation.

  11. Polysilicon photoconductor for integrated circuits

    DOEpatents

    Hammond, Robert B.; Bowman, Douglas R.

    1989-01-01

    A photoconductive element of polycrystalline silicon is provided with intrinsic response time which does not limit overall circuit response. An undoped polycrystalline silicon layer is deposited by LPCVD to a selected thickness on silicon dioxide. The deposited polycrystalline silicon is then annealed at a selected temperature and for a time effective to obtain crystal sizes effective to produce an enhanced current output. The annealed polycrystalline layer is subsequently exposed and damaged by ion implantation to a damage factor effective to obtain a fast photoconductive response.

  12. Polysilicon photoconductor for integrated circuits

    DOEpatents

    Hammond, Robert B.; Bowman, Douglas R.

    1990-01-01

    A photoconductive element of polycrystalline silicon is provided with intrinsic response time which does not limit overall circuit response. An undoped polycrystalline silicon layer is deposited by LPCVD to a selected thickness on silicon dioxide. The deposited polycrystalline silicon is then annealed at a selected temperature and for a time effective to obtain crystal sizes effective to produce an enhanced current output. The annealed polycrystalline layer is subsequently exposed and damaged by ion implantation to a damage factor effective to obtain a fast photoconductive response.

  13. Polysilicon photoconductor for integrated circuits

    DOEpatents

    Hammond, R.B.; Bowman, D.R.

    1989-04-11

    A photoconductive element of polycrystalline silicon is provided with intrinsic response time which does not limit overall circuit response. An undoped polycrystalline silicon layer is deposited by LPCVD to a selected thickness on silicon dioxide. The deposited polycrystalline silicon is then annealed at a selected temperature and for a time effective to obtain crystal sizes effective to produce an enhanced current output. The annealed polycrystalline layer is subsequently exposed and damaged by ion implantation to a damage factor effective to obtain a fast photoconductive response. 6 figs.

  14. Printed circuit dispersive transmission line

    DOEpatents

    Ikezi, H.; Lin-Liu, Y.R.; DeGrassie, J.S.

    1991-08-27

    A printed circuit dispersive transmission line structure is disclosed comprising an insulator, a ground plane formed on one surface of the insulator, a first transmission line formed on a second surface of the insulator, and a second transmission line also formed on the second surface of the insulator and of longer length than the first transmission line and periodically intersecting the first transmission line. In a preferred embodiment, the transmission line structure exhibits highly dispersive characteristics by designing the length of one of the transmission line between two adjacent periodic intersections to be longer than the other. 5 figures.

  15. Printed circuit dispersive transmission line

    DOEpatents

    Ikezi, Hiroyuki; Lin-Liu, Yuh-Ren; DeGrassie, John S.

    1991-01-01

    A printed circuit dispersive transmission line structure is disclosed comprising an insulator, a ground plane formed on one surface of the insulator, a first transmission line formed on a second surface of the insulator, and a second transmission line also formed on the second surface of the insulator and of longer length than the first transmission line and periodically intersecting the first transmission line. In a preferred embodiment, the transmission line structure exhibits highly dispersive characteristics by designing the length of one of the transmission line between two adjacent periodic intersections to be longer than the other.

  16. Two digital video encoder circuits

    NASA Astrophysics Data System (ADS)

    Eldon, John A.

    1992-11-01

    Central to `multimedia' image processing is the desire to encode computer graphics data into a standard television signal, complete with line, field, and color subcarrier synchronizing information. The numerous incompatibilities between television and computer display standards render this operation far less trivial than it sounds to anyone who hasn't worked with both types of signals. To simplify the task of encoding computer graphics signals into standard NTSC (North America and Japan) or PAL (most of Europe) television format for display, broadcast, or recording, TRW LSI Products Inc. has introduced the two newest members of it multimedia integrated circuit family, the TMC22090 and TMC22190 digital video encoders.

  17. Silicon sample holder for molecular beam epitaxy on pre-fabricated integrated circuits

    NASA Technical Reports Server (NTRS)

    Hoenk, Michael E. (Inventor); Grunthaner, Paula J. (Inventor); Grunthaner, Frank J. (Inventor)

    1994-01-01

    The sample holder of the invention is formed of the same semiconductor crystal as the integrated circuit on which the molecular beam expitaxial process is to be performed. In the preferred embodiment, the sample holder comprises three stacked micro-machined silicon wafers: a silicon base wafer having a square micro-machined center opening corresponding in size and shape to the active area of a CCD imager chip, a silicon center wafer micro-machined as an annulus having radially inwardly pointing fingers whose ends abut the edges of and center the CCD imager chip within the annulus, and a silicon top wafer micro-machined as an annulus having cantilevered membranes which extend over the top of the CCD imager chip. The micro-machined silicon wafers are stacked in the order given above with the CCD imager chip centered in the center wafer and sandwiched between the base and top wafers. The thickness of the center wafer is about 20% less than the thickness of the CCD imager chip. Preferably, four titanium wires, each grasping the edges of the top and base wafers, compress all three wafers together, flexing the cantilever fingers of the top wafer to accommodate the thickness of the CCD imager chip, acting as a spring holding the CCD imager chip in place.

  18. Automatic generation of signal processing integrated circuits

    SciTech Connect

    Pope, S.P.

    1985-01-01

    A system for the automated design of signal processing integrated circuits is described in this thesis. The system is based on a library of circuit cells, and a software package that can configure the cells into complete integrated circuits. The architecture of the cell library is optimized for low and medium bandwidth digital signal processing applications. Circuits designed with the system use a multiprocessor architecture. Input to the system is a design file written in a specialized programming language. Software emulation from the design file is used to verify performance. A two-pass silicon compiler is used to translate the design file into a mask-level description of an integrated circuit. A major goal of the project is to make the system useable by those with little or no formal training in integrated circuits. A second goal is to reduce the time and cost associated with performing an integrated circuit design, while still producing designs which are reasonably efficient in their use of the technology. Development of the system was guided by basic research on appropriate architectures and circuit constructs for signal processors. As part of this research an integrated circuit was designed which performs speech analysis and synthesis. This vocoder circuit is intended for use in low-bit-rate digital speech transmission systems.

  19. The p53 circuit board

    PubMed Central

    Sullivan, Kelly D.; Gallant-Behm, Corrie L.; Henry, Ryan E.; Fraikin, Jean-Luc; Espinosa, Joaquín M.

    2012-01-01

    The p53 tumor suppressor is embedded in a large gene network controlling diverse cellular and organismal phenotypes. Multiple signaling pathways converge onto p53 activation, mostly by relieving the inhibitory effects of its repressors, MDM2 and MDM4. In turn, signals originating from increased p53 activity diverge into distinct effector pathways to deliver a specific cellular response to the activating stimuli. Much attention has been devoted to dissecting how the various input pathways trigger p53 activation and how the activity of the p53 protein itself can be modulated by a plethora of co-factors and post-translational modifications. In this review we will focus instead on the multiple configurations of the effector pathways. We will discuss how p53-generated signals are transmitted, amplified, resisted and eventually integrated by downstream gene circuits operating at the transcriptional, post-transcriptional and post-translational level. We will also discuss how context-dependent variations in these gene circuits define the cellular response to p53 activation and how they may impact the clinical efficacy of p53-based targeted therapies. PMID:22333261

  20. Clocking and synchronization circuits in multiprocessor systems

    SciTech Connect

    Jeong, D.K.

    1989-01-01

    Microprocessors based on RISC (Reduced Instruction Set Computer) concepts have demonstrated an ability to provide more computing power at a given level of integration than conventional microprocessors. The next step is multiprocessors composed of RISC processing elements. Communication bandwidth among such microprocessors is critical in achieving efficient hardware utilization. This thesis focuses on the communication capability of VLSI circuits and presents new circuit techniques as a guide to build an interconnection network of VLSI microprocessors. Circuit techniques for PLL-based clock generation are described along with stability criteria. The main objective of the circuit is to realize a zero delay buffer. Experimental results show the feasibility of such circuits in VLSI. Synchronizer circuit configurations in both bipolar and MOS technology that best utilize each device, or overcome the technology limit using a bandwidth doubling technique are shown. Interface techniques including handshake mechanisms in such a system are also described.

  1. MULTI-ELECTRODE TUBE PULSE MEMORY CIRCUIT

    DOEpatents

    Gundlach, J.C.; Reeves, J.B.

    1958-05-20

    Control circuits are described for pulse memory devices for scalers and the like, and more particularly to a driving or energizing circuit for a polycathode gaseous discharge tube having an elongated anode and a successive series of cathodes spaced opposite the anode along its length. The circuit is so arranged as to utilize an arc discharge between the anode and a cathode to count a series of pulses. Upon application of an input pulse the discharge is made to occur between the anode and the next successive cathode, and an output pulse is produced when a particular subsequent cathode is reached. The circuit means for transfering the discharge by altering the anode potential and potential of the cathodes and interconnecting the cathodes constitutes the novel aspects of the invention. A low response time and reduced number of circuit components are the practical advantages of the described circuit.

  2. Diode-quad bridge circuit means

    NASA Technical Reports Server (NTRS)

    Harrison, D. R.; Dimeff, J. (Inventor)

    1975-01-01

    Diode-quad bridge circuit means is described for use as a transducer circuit or as a discriminator circuit. It includes: (1) a diode bridge having first, second, third, and fourth bridge terminals consecutively coupled together by four diodes polarized in circulating relationship; (2) a first impedance connected between the second bridge terminal and a circuit ground; (3) a second impedance connected between the fourth bridge terminal and the circuit ground; (4) a signal source having a first source terminal capacitively coupled to the first and third bridge terminals, and a second source terminal connected to the circuit ground; and (5) an output terminal coupled to the first bridge terminal and at which an output signal may be taken.

  3. Analog VLSI neural network integrated circuits

    NASA Technical Reports Server (NTRS)

    Kub, F. J.; Moon, K. K.; Just, E. A.

    1991-01-01

    Two analog very large scale integration (VLSI) vector matrix multiplier integrated circuit chips were designed, fabricated, and partially tested. They can perform both vector-matrix and matrix-matrix multiplication operations at high speeds. The 32 by 32 vector-matrix multiplier chip and the 128 by 64 vector-matrix multiplier chip were designed to perform 300 million and 3 billion multiplications per second, respectively. An additional circuit that has been developed is a continuous-time adaptive learning circuit. The performance achieved thus far for this circuit is an adaptivity of 28 dB at 300 KHz and 11 dB at 15 MHz. This circuit has demonstrated greater than two orders of magnitude higher frequency of operation than any previous adaptive learning circuit.

  4. Physical synthesis of quantum circuits using templates

    NASA Astrophysics Data System (ADS)

    Mirkhani, Zahra; Mohammadzadeh, Naser

    2016-06-01

    Similar to traditional CMOS circuits, quantum circuit design flow is divided into two main processes: logic synthesis and physical design. Addressing the limitations imposed on optimization of the quantum circuit metrics because of no information sharing between logic synthesis and physical design processes, the concept of "physical synthesis" was introduced for quantum circuit flow, and a few techniques were proposed for it. Following that concept, in this paper a new approach for physical synthesis inspired by template matching idea in quantum logic synthesis is proposed to improve the latency of quantum circuits. Experiments show that by using template matching as a physical synthesis approach, the latency of quantum circuits can be improved by more than 23.55 % on average.

  5. Gas-Sensing Flip-Flop Circuits

    NASA Technical Reports Server (NTRS)

    Buehler, Martin G.; Blaes, Brent R.; Williams, Roger; Ryan, Margaret A.

    1995-01-01

    Gas-sensing integrated circuits consisting largely of modified static random-access memories (SRAMs) undergoing development, building on experience gained in use of modified SRAMs as radiation sensors. Each SRAM memory cell includes flip-flop circuit; sensors exploit metastable state that lies between two stable states (corresponding to binary logic states) of flip-flop circuit. Voltages of metastable states vary with exposures of gas-sensitive resistors.

  6. Cost optimization in low volume VLSI circuits

    NASA Technical Reports Server (NTRS)

    Cook, K. B., Jr.; Kerns, D. V., Jr.

    1982-01-01

    The relationship of integrated circuit (IC) cost to electronic system cost is developed using models for integrated circuit cost which are based on design/fabrication approach. Emphasis is on understanding the relationship between cost and volume for custom circuits suitable for NASA applications. In this report, reliability is a major consideration in the models developed. Results are given for several typical IC designs using off the shelf, full custom, and semicustom IC's with single and double level metallization.

  7. Expert system to design communications circuits

    SciTech Connect

    Tolendino, L.F.; Vahle, M.O.

    1986-07-01

    An expert system has been created to aid the design of fiber optic based communications circuits. The design system is based on an Apollo workstation, LISP and CPSL, an in-house developed expert system language. The optical circuit is taken from design specification through hardware selection and circuit routing to the production of detailed schematics and routing guides. A database containing the entire fiber optic trunk system is also maintained.

  8. Integrated-Circuit Pseudorandom-Number Generator

    NASA Technical Reports Server (NTRS)

    Steelman, James E.; Beasley, Jeff; Aragon, Michael; Ramirez, Francisco; Summers, Kenneth L.; Knoebel, Arthur

    1992-01-01

    Integrated circuit produces 8-bit pseudorandom numbers from specified probability distribution, at rate of 10 MHz. Use of Boolean logic, circuit implements pseudorandom-number-generating algorithm. Circuit includes eight 12-bit pseudorandom-number generators, outputs are uniformly distributed. 8-bit pseudorandom numbers satisfying specified nonuniform probability distribution are generated by processing uniformly distributed outputs of eight 12-bit pseudorandom-number generators through "pipeline" of D flip-flops, comparators, and memories implementing conditional probabilities on zeros and ones.

  9. A microwave dielectric resonant oscillatory circuit

    NASA Astrophysics Data System (ADS)

    Sigov, A. S.; Shvartsburg, A. B.

    2016-07-01

    Bias currents in a thin dielectric nonconducting torus are investigated, and the resonant mode of excitation of these currents is established. The similarity of the frequency spectrum of such a dielectric element to the spectra of a classical Thomson oscillatory circuit and a metamaterial with negative permittivity is demonstrated. The resonant frequency of electromagnetic oscillations of the ring dielectric circuit and magnetic and electric fields of such a circuit under resonant excitation are determined.

  10. Multiplexer and time duration measuring circuit

    SciTech Connect

    Gray, Jr., James

    1980-01-01

    A multiplexer device is provided for multiplexing data in the form of randomly developed, variable width pulses from a plurality of pulse sources to a master storage. The device includes a first multiplexer unit which includes a plurality of input circuits each coupled to one of the pulse sources, with all input circuits being disabled when one input circuit receives an input pulse so that only one input pulse is multiplexed by the multiplexer unit at any one time.

  11. Modeling of transformers using circuit simulators

    SciTech Connect

    Archer, W.E.; Deveney, M.F.; Nagel, R.L.

    1994-07-01

    Transformers of two different designs; and unencapsulated pot core and an encapsulated toroidal core have been modeled for circuit analysis with circuit simulation tools. We selected MicroSim`s PSPICE and Anology`s SABER as the simulation tools and used experimental BH Loop and network analyzer measurements to generate the needed input data. The models are compared for accuracy and convergence using the circuit simulators. Results are presented which demonstrate the effects on circuit performance from magnetic core losses, eddy currents, and mechanical stress on the magnetic cores.

  12. Circuit For Control Of Electromechanical Prosthetic Hand

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr.

    1995-01-01

    Proposed circuit for control of electromechanical prosthetic hand derives electrical control signals from shoulder movements. Updated, electronic version of prosthesis, that includes two hooklike fingers actuated via cables from shoulder harness. Circuit built around favored shoulder harness, provides more dexterous movement, without incurring complexity of computer-controlled "bionic" or hydraulically actuated devices. Additional harness and potentiometer connected to similar control circuit mounted on other shoulder. Used to control stepping motor rotating hand about prosthetic wrist to one of number of angles consistent with number of digital outputs. Finger-control signals developed by circuit connected to first shoulder harness transmitted to prosthetic hand via sliprings at prosthetic wrist joint.

  13. High Speed Solid State Circuit Breaker

    NASA Technical Reports Server (NTRS)

    Podlesak, Thomas F.

    1993-01-01

    The U.S. Army Research Laboratory, Fort Monmouth, NJ, has developed and is installing two 3.3 MW high speed solid state circuit breakers at the Army's Pulse Power Center. These circuit breakers will interrupt 4160V three phase power mains in no more than 300 microseconds, two orders of magnitude faster than conventional mechanical contact type circuit breakers. These circuit breakers utilize Gate Turnoff Thyristors (GTO's) and are currently utility type devices using air cooling in an air conditioned enclosure. Future refinements include liquid cooling, either water or two phase organic coolant, and more advanced semiconductors. Each of these refinements promises a more compact, more reliable unit.

  14. Thermionic integrated circuit program: Final report

    SciTech Connect

    Wilde, D.K.; Lynn, D.K.; Hamilton, D.

    1988-05-01

    This report describes the development of an operational amplifier using radiation hardened Thermionic Integrated Circuits (TICs). The report is written as a tutorial to cover all aspects of the fabrication process and circuit development as well as the process and circuit modifications required to meet the integration requirements of the operational amplifier. Recent experimental results are discussed in which both devices and test circuit data are compared to theoretical computer code predictions. The development of compatible high-temperature thin-film resistors is also presented. Because the project is being terminated prior to the completion of the amplifier, suggestions are made for additional advance development.

  15. High temperature superconducting digital circuits and subsystems

    SciTech Connect

    Martens, J.S.; Pance, A.; Whiteley, S.R.; Char, K.; Johansson, M.F.; Lee, L.; Hietala, V.M.; Wendt, J.R.; Hou, S.Y.; Phillips, J.

    1993-10-01

    The advances in the fabrication of high temperature superconducting devices have enabled the demonstration of high performance and useful digital circuits and subsystems. The yield and uniformity of the devices is sufficient for circuit fabrication at the medium scale integration (MSI) level with performance not seen before at 77 K. The circuits demonstrated to date include simple gates, counters, analog to digital converters, and shift registers. All of these are mid-sized building blocks for potential applications in commercial and military systems. The processes used for these circuits and blocks will be discussed along with observed performance data.

  16. Quantization of lumped elements electrical circuits revisited

    NASA Astrophysics Data System (ADS)

    Lalumiere, Kevin; Najafi­-Yazdi, Alireza

    In 1995, the ``Les Houches'' seminar of Michel Devoret introduced a method to quantize lumped elements electrical circuits. This method has since been formalized using the matricial formalism, in particular by G. Burkard. Starting from these seminal contributions, we present a new algorithm to quantify electrical circuits. This algorithm unites the features of Devoret's and Burkad's approaches. We minimize the set of assumptions made so that the method can treat directly most electrical circuits. This includes circuits with resistances, mutual inductances, voltage and current sources. We conclude with a discussion about the choice of the basis in which the Hamiltonian operator should be written, an issue which is often overlooked.

  17. Q-switched laser prelase detection circuit

    NASA Technical Reports Server (NTRS)

    Lockard, George E.

    1991-01-01

    A compact electronic circuit was developed to detect prelasing in Q-swithed pulsed laser systems and once detected to shut down the laser before the next laser pulse occurs. The circuit is small, compact, and uses a minimum of components which makes it quite economical, thus readily lending itself to commercial applications. It can easily be incorporated into virtually any Q-switched laser system or reliability of a laser system by reducing a source of possible costly optical damage. The circuit operation and instrument requirements necessary to incorporate the circuit into a laser system are discussed.

  18. Digital circuits for computer applications: A compilation

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The innovations in this updated series of compilations dealing with electronic technology represent a carefully selected collection of digital circuits which have direct application in computer oriented systems. In general, the circuits have been selected as representative items of each section and have been included on their merits of having universal applications in digital computers and digital data processing systems. As such, they should have wide appeal to the professional engineer and scientist who encounter the fundamentals of digital techniques in their daily activities. The circuits are grouped as digital logic circuits, analog to digital converters, and counters and shift registers.

  19. Hybrid stretchable circuits on silicone substrate

    SciTech Connect

    Robinson, A. Aziz, A.; Liu, Q.; Suo, Z.; Lacour, S. P.

    2014-04-14

    When rigid and stretchable components are integrated onto a single elastic carrier substrate, large strain heterogeneities appear in the vicinity of the deformable-non-deformable interfaces. In this paper, we report on a generic approach to manufacture hybrid stretchable circuits where commercial electronic components can be mounted on a stretchable circuit board. Similar to printed circuit board development, the components are electrically bonded on the elastic substrate and interconnected with stretchable electrical traces. The substrate—a silicone matrix carrying concentric rigid disks—ensures both the circuit elasticity and the mechanical integrity of the most fragile materials.

  20. Precision measurements of a simple chaotic circuit

    NASA Astrophysics Data System (ADS)

    Kiers, Ken; Schmidt, Dory; Sprott, J. C.

    2004-04-01

    We describe a simple nonlinear electrical circuit that can be used to study chaotic phenomena. The circuit employs simple electronic elements such as diodes, resistors, and operational amplifiers, and is easy to construct. A novel feature of the circuit is its use of an almost ideal nonlinear element, which is straightforward to model theoretically and leads to excellent agreement between experiment and theory. For example, comparisons of bifurcation points and power spectra give agreement to within 1%. The circuit yields a broad range of behavior and is well suited for qualitative demonstrations and as a serious research tool.

  1. Towards programmable plant genetic circuits.

    PubMed

    Medford, June I; Prasad, Ashok

    2016-07-01

    Synthetic biology enables the construction of genetic circuits with predictable gene functions in plants. Detailed quantitative descriptions of the transfer function or input-output function for genetic parts (promoters, 5' and 3' untranslated regions, etc.) are collected. These data are then used in computational simulations to determine their robustness and desired properties, thereby enabling the best components to be selected for experimental testing in plants. In addition, the process forms an iterative workflow which allows vast improvement to validated elements with sub-optimal function. These processes enable computational functions such as digital logic in living plants and follow the pathway of technological advances which took us from vacuum tubes to cell phones. PMID:27297052

  2. TIME CALIBRATED OSCILLOSCOPE SWEEP CIRCUIT

    DOEpatents

    Smith, V.L.; Carstensen, H.K.

    1959-11-24

    An improved time calibrated sweep circuit is presented, which extends the range of usefulness of conventional oscilloscopes as utilized for time calibrated display applications in accordance with U. S. Patent No. 2,832,002. Principal novelty resides in the provision of a pair of separate signal paths, each of which is phase and amplitude adjustable, to connect a high-frequency calibration oscillator to the output of a sawtooth generator also connected to the respective horizontal deflection plates of an oscilloscope cathode ray tube. The amplitude and phase of the calibration oscillator signals in the two signal paths are adjusted to balance out feedthrough currents capacitively coupled at high frequencies of the calibration oscillator from each horizontal deflection plate to the vertical plates of the cathode ray tube.

  3. Flexible phosphorene devices and circuits

    NASA Astrophysics Data System (ADS)

    Zhu, Weinan; Yogeesh, Maruthi N.; Akinwande, Deji

    2015-05-01

    Two-dimensional (2D) semiconductors with high carrier mobilities and sizeable bandgap are desirable for future high-speed and low power mechanically flexible nanoelectronics. In this work, we report encapsulated bottom-gated black phosphorus (BP) field-effect transistors (FETs) on flexible polyimide affording maximum carrier mobility of about 310cm2/V•s and current on/off ratio exceeding 103. Essential circuits of flexible electronic systems enabled by the device ambipolar functionality, high-mobility and current saturation are demonstrated in this work, including digital inverter, frequency doubler, and analog amplifiers featuring a voltage gain of ~8.7, which is the state-of-the-art value for flexible 2D semiconductor based amplifiers. In addition, we demonstrate the single FET based flexible BP amplitude-modulated (AM) demodulator, an active stage in radio receivers.

  4. Atemporal diagrams for quantum circuits

    SciTech Connect

    Griffiths, Robert B.; Wu Shengjun; Yu Li; Cohen, Scott M.

    2006-05-15

    A system of diagrams is introduced that allows the representation of various elements of a quantum circuit, including measurements, in a form which makes no reference to time (hence 'atemporal'). It can be used to relate quantum dynamical properties to those of entangled states (map-state duality), and suggests useful analogies, such as the inverse of an entangled ket. Diagrams clarify the role of channel kets, transition operators, dynamical operators (matrices), and Kraus rank for noisy quantum channels. Positive (semidefinite) operators are represented by diagrams with a symmetry that aids in understanding their connection with completely positive maps. The diagrams are used to analyze standard teleportation and dense coding, and for a careful study of unambiguous (conclusive) teleportation. A simple diagrammatic argument shows that a Kraus rank of 3 is impossible for a one-qubit channel modeled using a one-qubit environment in a mixed state.

  5. Semiconductor materials and microelectronic circuits

    NASA Astrophysics Data System (ADS)

    Kolesar, Edward S.

    Microminiaturization developments in IC systems have dramatically increased the reliability and performance of electronic components while reducing their physical size and power requirements; these advancements have pervasively affected weapons systems design efforts. Built-in self-test circuitry has greatly reduced maintenance problems and improved overall systems reliability. Increasing circuit complexity has also led to a major expansion of key military operational capabilities for reconnaissance, surveillance, and target acquisition. It is expected that Si-based ICs will continue to dominate high power solid-state switches in hypervelocity projectiles and beam weapons, while GaAs will remain the most commonly employed material in microwave and mm-wave devices for EW, radars, smart weapons, and communications.

  6. Sequential power-up circuit

    DOEpatents

    Kronberg, James W.

    1992-01-01

    A sequential power-up circuit for starting several electrical load elements in series to avoid excessive current surge, comprising a voltage ramp generator and a set of voltage comparators, each comparator having a different reference voltage and interfacing with a switch that is capable of turning on one of the load elements. As the voltage rises, it passes the reference voltages one at a time and causes the switch corresponding to that voltage to turn on its load element. The ramp is turned on and off by a single switch or by a logic-level electrical signal. The ramp rate for turning on the load element is relatively slow and the rate for turning the elements off is relatively fast. Optionally, the duration of each interval of time between the turning on of the load elements is programmable.

  7. Sequential power-up circuit

    DOEpatents

    Kronberg, J.W.

    1992-06-02

    A sequential power-up circuit for starting several electrical load elements in series to avoid excessive current surge, comprising a voltage ramp generator and a set of voltage comparators, each comparator having a different reference voltage and interfacing with a switch that is capable of turning on one of the load elements. As the voltage rises, it passes the reference voltages one at a time and causes the switch corresponding to that voltage to turn on its load element. The ramp is turned on and off by a single switch or by a logic-level electrical signal. The ramp rate for turning on the load element is relatively slow and the rate for turning the elements off is relatively fast. Optionally, the duration of each interval of time between the turning on of the load elements is programmable. 2 figs.

  8. Shapeable short circuit resistant capacitor

    DOEpatents

    Taylor, Ralph S.; Myers, John D.; Baney, William J.

    2015-10-06

    A ceramic short circuit resistant capacitor that is bendable and/or shapeable to provide a multiple layer capacitor that is extremely compact and amenable to desirable geometries. The capacitor that exhibits a benign failure mode in which a multitude of discrete failure events result in a gradual loss of capacitance. Each event is a localized event in which localized heating causes an adjacent portion of one or both of the electrodes to vaporize, physically cleaning away electrode material from the failure site. A first metal electrode, a second metal electrode, and a ceramic dielectric layer between the electrodes are thin enough to be formed in a serpentine-arrangement with gaps between the first electrode and the second electrode that allow venting of vaporized electrode material in the event of a benign failure.

  9. Integrated Circuit Electromagnetic Immunity Handbook

    NASA Astrophysics Data System (ADS)

    Sketoe, J. G.

    2000-08-01

    This handbook presents the results of the Boeing Company effort for NASA under contract NAS8-98217. Immunity level data for certain integrated circuit parts are discussed herein, along with analytical techniques for applying the data to electronics systems. This handbook is built heavily on the one produced in the seventies by McDonnell Douglas Astronautics Company (MDAC, MDC Report E1929 of 1 August 1978, entitled Integrated Circuit Electromagnetic Susceptibility Handbook, known commonly as the ICES Handbook, which has served countless systems designers for over 20 years). Sections 2 and 3 supplement the device susceptibility data presented in section 4 by presenting information on related material required to use the IC susceptibility information. Section 2 concerns itself with electromagnetic susceptibility analysis and serves as a guide in using the information contained in the rest of the handbook. A suggested system hardening requirements is presented in this chapter. Section 3 briefly discusses coupling and shielding considerations. For conservatism and simplicity, a worst case approach is advocated to determine the maximum amount of RF power picked up from a given field. This handbook expands the scope of the immunity data in this Handbook is to of 10 MHz to 10 GHz. However, the analytical techniques provided are applicable to much higher frequencies as well. It is expected however, that the upper frequency limit of concern is near 10 GHz. This is due to two factors; the pickup of microwave energy on system cables and wiring falls off as the square of the wavelength, and component response falls off at a rapid rate due to the effects of parasitic shunt paths for the RF energy. It should be noted also that the pickup on wires and cables does not approach infinity as the frequency decreases (as would be expected by extrapolating the square law dependence of the high frequency roll-off to lower frequencies) but levels off due to mismatch effects.

  10. 49 CFR 236.5 - Design of control circuits on closed circuit principle.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Design of control circuits on closed circuit principle. 236.5 Section 236.5 Transportation Other Regulations Relating to Transportation (Continued..., AND APPLIANCES Rules and Instructions: All Systems General § 236.5 Design of control circuits...

  11. Thermal remote sensing from Airborne Hyperspectral Scanner data in the framework of the SPARC and SEN2FLEX projects: an overview

    NASA Astrophysics Data System (ADS)

    Sobrino, J. A.; Jiménez-Muñoz, J. C.; Zarco-Tejada, P. J.; Sepulcre-Cantó, G.; de Miguel, E.; Sòria, G.; Romaguera, M.; Julien, Y.; Cuenca, J.; Hidalgo, V.; Franch, B.; Mattar, C.; Morales, L.; Gillespie, A.; Sabol, D.; Balick, L.; Su, Z.; Jia, L.; Gieske, A.; Timmermans, W.; Olioso, A.; Nerry, F.; Guanter, L.; Moreno, J.; Shen, Q.

    2009-06-01

    The AHS (Airborne Hyperspectral Scanner) instrument has 80 spectral bands covering the visible and near infrared (VNIR), short wave infrared (SWIR), mid infrared (MIR) and thermal infrared (TIR) spectral range. The instrument is operated by Instituto Nacional de Técnica Aerospacial (INTA), and it has been involved in several field campaigns since 2004. This paper presents an overview of the work performed with the AHS thermal imagery provided in the framework of the SPARC and SEN2FLEX campaigns, carried out respectively in 2004 and 2005 over an agricultural area in Spain. The data collected in both campaigns allowed for the first time the development and testing of algorithms for land surface temperature and emissivity retrieval as well as the estimation of evapotranspiration from AHS data. Errors were found to be around 1.5 K for land surface temperature and 1 mm/day for evapotranspiration.

  12. Thermal remote sensing from Airborne Hyperspectral Scanner data in the framework of the SPARC and SEN2FLEX projects: an overview

    NASA Astrophysics Data System (ADS)

    Sobrino, J. A.; Jiménez-Muñoz, J. C.; Zarco-Tejada, P. J.; Sepulcre-Cantó, G.; de Miguel, E.; Sòria, G.; Romaguera, M.; Julien, Y.; Cuenca, J.; Hidalgo, V.; Franch, B.; Mattar, C.; Morales, L.; Gillespie, A.; Sabol, D.; Balick, L.; Su, Z.; Jia, L.; Gieske, A.; Timmermans, W.; Olioso, A.; Nerry, F.; Guanter, L.; Moreno, J.; Shen, Q.

    2009-11-01

    The AHS (Airborne Hyperspectral Scanner) instrument has 80 spectral bands covering the visible and near infrared (VNIR), short wave infrared (SWIR), mid infrared (MIR) and thermal infrared (TIR) spectral range. The instrument is operated by Instituto Nacional de Técnica Aerospacial (INTA), and it has been involved in several field campaigns since 2004. This paper presents an overview of the work performed with the AHS thermal imagery provided in the framework of the SPARC and SEN2FLEX campaigns, carried out respectively in 2004 and 2005 over an agricultural area in Spain. The data collected in both campaigns allowed for the first time the development and testing of algorithms for land surface temperature and emissivity retrieval as well as the estimation of evapotranspiration from AHS data. Errors were found to be around 1.5 K for land surface temperature and 1 mm/day for evapotranspiration.

  13. Cobrahead Deformity in the Right Atrial Disc of a New-Generation Occlutech Figulla Flex II Atrial Septal Defect Occluder Device

    PubMed Central

    Ural, Ertan; Sahin, Tayfun

    2015-01-01

    Cobrahead deformity is a known (but uncommon) phenomenon associated with the left atrial disc of the Amplatzer or Occlutech Figulla septal occluder device during percutaneous transcatheter atrial septal defect closure. It has also been postulated that the right atrial disc of the Amplatzer septal occluder device might upon occasion exhibit the cobrahead malformation. To date, only one case report concerning the cobrahead deformity in the right atrial disc of an Amplatzer septal occluder has been published, if we discount a report published as a letter to the manufacturer. Here we present the first report (known to us) of a cobrahead deformity in the right atrial disc of an Occlutech Figulla Flex II atrial septal defect occluder device during transcatheter closure of a complex atrial septal defect. PMID:26504440

  14. Clinical outcomes in 995 unselected real-world patients treated with an ultrathin biodegradable polymer-coated sirolimus-eluting stent: 12-month results from the FLEX Registry

    PubMed Central

    Lemos, Pedro A; Chandwani, Prakash; Saxena, Sudheer; Ramachandran, Padma Kumar; Abhyankar, Atul; Campos, Carlos M; Marchini, Julio Flavio; Galon, Micheli Zanotti; Verma, Puneet; Sandhu, Manjinder Singh; Parikh, Nikhil; Bhupali, Ashok; Jain, Sharad; Prajapati, Jayesh

    2016-01-01

    Objectives To evaluate, in the FLEX Registry, clinical outcomes of an ultrathin (60 µm) biodegradable polymer-coated Supraflex sirolimus-eluting stent (SES) for the treatment of coronary artery disease. Additionally, to determine the vascular response to the Supraflex SES through optical coherence tomography (OCT) analysis. Setting Multicentre, single-arm, all-comers, observational registry of patients who were treated with the Supraflex SES, between July 2013 and May 2014, at nine different centres in India. Participants 995 patients (1242 lesions) who were treated with the Supraflex SES, between July 2013 and May 2014, at nine different centres in India. A total of 47 participants underwent OCT analysis at 6 months’ follow-up. Interventions Percutaneous coronary intervention with Supraflex SES, Primary and secondary outcome measures The primary endpoint—the rate of major adverse cardiac events (defined as a composite of cardiac death, myocardial infarction (MI), target lesion revascularisation (TLR))—was analysed during 12 months. Results At 12 months, the primary endpoint occurred in 36 (3.7%) of 980 patients, consisting of 18 (1.8%) cardiac deaths, 16 (1.6%) MI, 7 (0.7%) TLR and 2 (0.2%) cases of non-target lesion target vessel revascularization. In a subset of 47 patients, 1227 cross-sections (9309 struts) were analysed at 6 months by OCT. Overall, a high percentage of struts was covered (98.1%), with a mean neointimal thickness of 0.13±0.06 µm. Conclusions The FLEX Registry evaluated clinical outcomes in real-world and more complex cohorts and thus provides evidence that the Supraflex SEX can be used safely and routinely in a broader percutaneous coronary intervention population. Also, the Supraflex SES showed high percentage of stent strut coverage and good stent apposition during OCT follow-up. PMID:26888727

  15. A Better Way to Drive "RLC" Circuits

    ERIC Educational Resources Information Center

    Aguilar, Horacio Munguia

    2009-01-01

    An electronic circuit for controlling "RLC" experiments is shown. This arrangement does not employ a function generator, which makes it more suitable when a wide range of "R," "L" and "C" values is required and a relatively high current is involved. This circuit can be used for driven and undriven DC experiments. (Contains 5 figures.)

  16. Analysis of circuits including magnetic cores (MTRAC)

    NASA Technical Reports Server (NTRS)

    Hanzen, G. R.; Nitzan, D.; Herndon, J. R.

    1972-01-01

    Development of automated circuit analysis computer program to provide transient analysis of circuits with magnetic cores is discussed. Allowance is made for complications caused by nonlinearity of switching core model and magnetic coupling among loop currents. Computer program is conducted on Univac 1108 computer using FORTRAN IV.

  17. Circuit II--A Conversational Graphical Interface.

    ERIC Educational Resources Information Center

    Singer, Ronald A.

    1993-01-01

    Provides an overview of Circuit II, an interactive system that provides users with a graphical representation of an electronic circuit within which questions may be posed and manipulated, and discusses how mouse selections have analogous roles to certain natural language features, such as anaphora, deixis, and ellipsis. (13 references) (EA)

  18. Apollo 14 mission circuit breaker anomaly

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Continuity through the circuit breaker in the mechanically closed condition was prevented by a foreign substance on the contact surface onboard Apollo 14. It was concluded that this was the only failure of this type in over 3400 units that were flown, and since no circuit breaker is a single-point failure for crew safety or mission success, no corrective action was taken.

  19. A Differential Magnetic Circuit for Teaching Purposes

    ERIC Educational Resources Information Center

    Kraftmakher, Yaakov

    2010-01-01

    A differential magnetic circuit (magnetic bridge) is described. The circuit separates the magnetic field sensor and the sample under study. A Hall probe serves as the sensor. The signal from the sensor can be enhanced by concentrating the magnetic flux. The magnetic bridge works even with dc magnetic fields. The device is used for displaying…

  20. Control of oscillations in a discharge circuit

    NASA Technical Reports Server (NTRS)

    Cheng, D. Y.

    1972-01-01

    Development of electric discharge circuit damping element which increases in resistance with current and time is described. Damping element is resistor made of tungsten wire which has large resistance-temperature coefficient. Specifications of tungsten resistor and incorporation into circuit are explained.