Architecture Design and Experimental Platform Demonstration of Optical Network based on OpenFlow Protocol

NASA Astrophysics Data System (ADS)

Xing, Fangyuan; Wang, Honghuan; Yin, Hongxi; Li, Ming; Luo, Shenzi; Wu, Chenguang

2016-02-01

With the extensive application of cloud computing and data centres, as well as the constantly emerging services, the big data with the burst characteristic has brought huge challenges to optical networks. Consequently, the software defined optical network (SDON) that combines optical networks with software defined network (SDN), has attracted much attention. In this paper, an OpenFlow-enabled optical node employed in optical cross-connect (OXC) and reconfigurable optical add/drop multiplexer (ROADM), is proposed. An open source OpenFlow controller is extended on routing strategies. In addition, the experiment platform based on OpenFlow protocol for software defined optical network, is designed. The feasibility and availability of the OpenFlow-enabled optical nodes and the extended OpenFlow controller are validated by the connectivity test, protection switching and load balancing experiments in this test platform.

Radiation hard vacuum switch

DOEpatents

Boettcher, Gordon E.

1990-01-01

A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction.

A radiation hard vacuum switch

DOEpatents

Boettcher, G.E.

1988-07-19

A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction. 3 figs.

Radiation hard vacuum switch

DOEpatents

Boettcher, Gordon E.

1990-03-06

A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction.

Slow domain reconfiguration causes power-law kinetics in a two-state enzyme.

PubMed

Grossman-Haham, Iris; Rosenblum, Gabriel; Namani, Trishool; Hofmann, Hagen

2018-01-16

Protein dynamics are typically captured well by rate equations that predict exponential decays for two-state reactions. Here, we describe a remarkable exception. The electron-transfer enzyme quiescin sulfhydryl oxidase (QSOX), a natural fusion of two functionally distinct domains, switches between open- and closed-domain arrangements with apparent power-law kinetics. Using single-molecule FRET experiments on time scales from nanoseconds to milliseconds, we show that the unusual open-close kinetics results from slow sampling of an ensemble of disordered domain orientations. While substrate accelerates the kinetics, thus suggesting a substrate-induced switch to an alternative free energy landscape of the enzyme, the power-law behavior is also preserved upon electron load. Our results show that the slow sampling of open conformers is caused by a variety of interdomain interactions that imply a rugged free energy landscape, thus providing a generic mechanism for dynamic disorder in multidomain enzymes.

Plasma-filled applied B ion diode experiments using a plasma opening switch

DOE Office of Scientific and Technical Information (OSTI.GOV)

Renk, T.J.

1994-12-15

In order for a plasma opening switch (POS) to open quickly and transfer power efficiently from an inductively charged vacuum transmission line to an applied B ion diode, the load impedance of the ion diode may be required to have an initial low impedance phase. A plasma-filled diode has such an impedance history. To test the effect of a plasma-filled diode on POS-diode coupling, a drifting plasma was introduced from the cathode side of an applied B ion diode operated on the LION accelerator (1.5 MV, 4 [Omega], 40 ns) at Cornell University. This plasma readily crossed the 2.1 Tmore » magnetic insulation field of the diode, and resulted in both increased diode electrical power, and an increased ability of the ion beam to remove material from a target. The plasma did not appear to have a noticeable effect on local beam steering angle.« less

Experiments Aimed at the ``Baikal'' Program

NASA Astrophysics Data System (ADS)

Kingsep, Alexander; Bakshaev, Yuri; Bartov, Alexander; Blinov, Petr; Chernenko, Andrey; Danko, Sergey; Dolgachev, Georgy; Kalinin, Yuri; Kovalenko, Igor; Lobanov, Alexey; Maslennikov, Dmitri; Mizhiritsky, Valery; Shashkov, Andrey; Smirnov, Valentin

2002-12-01

On the S-300 pulsed power generator (4.5 MA, 70 ns, 0.15 Ohm), within the frames of ICF program based on fast high-current Z-pinches, experiments are being carried out studying promising schemes of output units. In particular, a nanosecond-range plasma flow switch is being investigated aimed at sharpening the pulse. As a result, the switching rate as high as 2.5 MA / 2.5 ns has been achieved. The numerical simulation of such a device has been carried out. The results of experiments on the extrinsic magnetic field influence on high-impedance plasma opening switch (POS) operation are reported. It has been demonstrated that the POS output voltage could be increased by the factor of 1.5 compared to the POS free of an extrinsic field. Also the possibility of the expansion of POS conduction phase duration up to 40 μs has been presented. The development of more new laser and nuclear diagnostic methods will definitely contribute to attain new data which could help in understanding the POS operation physics.

Restrike Particle Beam Experiments on a Dense Plasma Focus.

DTIC Science & Technology

1981-11-30

particle beams generated in a plasma focus with the current flowing in the circuit just before the radial collapse of the pinch, IMB. The results show...the implications for the application of the plasma focus as an opening switch are discussed. (Author)

Current-level triggered plasma-opening switch

DOEpatents

Mendel, C.W.

1987-06-29

An opening switch for very high power electrical pulses uses a slow magnetic field to confine a plasma across a gap between two electrodes. The plasma conducts the electric pulse across the gap while the switch is closed. A magnetic field generated by the pulse repels the slow magnetic field from the negative electrode to push the plasma from the electrode, opening the switch. A plurality of radial vanes may be used to enhance the slow magnetic field. 5 figs.

Current-level triggered plasma-opening switch

DOEpatents

Mendel, Clifford W.

1989-01-01

An opening switch for very high power electrical pulses uses a slow magnetic field to confine a plasma across a gap between two electrodes. The plasma conducts the electric pulse across the gap while the switch is closed. A magnetic field generated by the pulse repels the slow magnetic field from the negative electrode to push the plasma from the electrode, opening the switch. A plurality of radial vanes may be used to enhance the slow magnetic field.

Research and Development of Anti-G Life Support Systems. Part 1. Development and Evaluation of Uniform-Pressure Anti-G Suits

DTIC Science & Technology

1987-04-01

Pressure Switch Control Circuit . . . . . . ........ 14 13. Pressure Switch Calibration Fixture . . .......... 16...with the pressure switch control oirouit boards. The solenoid oonneoto (SOL) interfaces with the PCD, while the function of the pressure switch (PRESS...signal out 4 Pressure switch (415 VDC) 5 Pressure switch return 6 + 15 VDC CVCC) V 15 VDC (VEE) 8 Instrument ground 9 open 10 Open 11 115 VAC hot (Blk)

Plasma density evolution in plasma opening switch obtained by a time-resolved sensitive He-Ne interferometer

NASA Astrophysics Data System (ADS)

Chen, Lin; Ren, Jing; Guo, Fan; Zhou, LiangJi; Li, Ye; He, An; Jiang, Wei

2014-03-01

To understand the formation process of vacuum gap in coaxial microsecond conduction time plasma opening switch (POS), we have made measurements of the line-integrated plasma density during switch operation using a time-resolved sensitive He-Ne interferometer. The conduction current and conduction time in experiments are about 120 kA and 1 μs, respectively. As a result, more than 85% of conduction current has been transferred to an inductive load with rise time of 130 ns. The radial dependence of the density is measured by changing the radial location of the line-of-sight for shots with the same nominal POS parameters. During the conduction phase, the line-integrated plasma density in POS increases at all radial locations over the gun-only case by further ionization of material injected from the guns. The current conduction is observed to cause a radial redistribution of the switch plasma. A vacuum gap forms rapidly in the plasma at 5.5 mm from the center conductor, which is consistent with the location where magnetic pressure is the largest, allowing current to be transferred from the POS to the load.

On Subsurface Fracture Opening and Closure

NASA Astrophysics Data System (ADS)

Wang, Y.

2016-12-01

Mechanistic understanding of fracture opening and closure in geologic media is of significant importance to nature resource extraction and waste management, such as geothermal energy extraction, oil/gas production, radioactive waste disposal, and carbon sequestration and storage). A dynamic model for subsurface fracture opening and closure has been formulated. The model explicitly accounts for the stress concentration around individual aperture channels and the stress-activated mineral dissolution and precipitation. A preliminary model analysis has demonstrated the importance of the stress-activated dissolution mechanism in the evolution of fracture aperture in a stressed geologic medium. The model provides a reasonable explanation for some key features of fracture opening and closure observed in laboratory experiments, including a spontaneous switch from a net permeability reduction to a net permeability increase with no changes in a limestone fracture experiment.

Opening Switch Research on a Dense Plasma Focus.

DTIC Science & Technology

Several experiments were performed to enhance power coupling to the load by placing the load electrode opposite the muzzle end of the Dense Plasma ... Focus plasma gun. The impaler concept, whereby the current sheath is run into a knife edge insulator, was tested in two configurations. However, the

Theoretical Modeling of the Plasma Erosion Opening Switch for Inductive Storage Applications.

DTIC Science & Technology

1983-10-27

instantaneous and depends on the switch and load characteristics. In general T is finite and T >T >0. Thus energy will be lost to switch heatings s op - as...Top, then the switch opening time is the dominant factor and T T Clearly T must be small compared with the decay time of the load S op 5 current, T_

Solid state pulsed power generator

DOEpatents

Tao, Fengfeng; Saddoughi, Seyed Gholamali; Herbon, John Thomas

2014-02-11

A power generator includes one or more full bridge inverter modules coupled to a semiconductor opening switch (SOS) through an inductive resonant branch. Each module includes a plurality of switches that are switched in a fashion causing the one or more full bridge inverter modules to drive the semiconductor opening switch SOS through the resonant circuit to generate pulses to a load connected in parallel with the SOS.

Multi-gap high impedance plasma opening switch

DOEpatents

Mason, Rodney J.

1996-01-01

A high impedance plasma opening switch having an anode and a cathode and at least one additional electrode placed between the anode and cathode. The presence of the additional electrodes leads to the creation of additional plasma gaps which are in series, increasing the net impedance of the switch. An equivalent effect can be obtained by using two or more conventional plasma switches with their plasma gaps wired in series. Higher impedance switches can provide high current and voltage to higher impedance loads such as plasma radiation sources.

System for automatically switching transformer coupled lines

NASA Technical Reports Server (NTRS)

Dwinell, W. S. (Inventor)

1979-01-01

A system is presented for automatically controlling transformer coupled alternating current electric lines. The secondary winding of each transformer is provided with a center tap. A switching circuit is connected to the center taps of a pair of secondary windings and includes a switch controller. An impedance is connected between the center taps of the opposite pair of secondary windings. The switching circuit has continuity when the AC lines are continuous and discontinuity with any disconnect of the AC lines. Normally open switching means are provided in at least one AC line. The switch controller automatically opens the switching means when the AC lines become separated.

Electronic logic to enhance switch reliability in detecting openings and closures of redundant switches

DOEpatents

Cooper, James A.

1986-01-01

A logic circuit is used to enhance redundant switch reliability. Two or more switches are monitored for logical high or low output. The output for the logic circuit produces a redundant and failsafe representation of the switch outputs. When both switch outputs are high, the output is high. Similarly, when both switch outputs are low, the logic circuit's output is low. When the output states of the two switches do not agree, the circuit resolves the conflict by memorizing the last output state which both switches were simultaneously in and produces the logical complement of this output state. Thus, the logic circuit of the present invention allows the redundant switches to be treated as if they were in parallel when the switches are open and as if they were in series when the switches are closed. A failsafe system having maximum reliability is thereby produced.

Effects of AEA Cell-Bypass-Switch Closure on Charged EOS-Aqua NiH2 Cell

NASA Technical Reports Server (NTRS)

Keys, Denney; Rao, Gopalakrishna M.; Sullivan, David; Wannemacher, Harry

2001-01-01

The nominal performance of AEA CBPD under simulated EOS-Aqua/Aura flight hardware configuration has been demonstrated. There is no evidence of cell rupture or excessive heat production during or after CBPD switch activation under simulated high cell impedance (open-circuit cell failure mode). Inadvertent CBPD switch activation with a charged cell (low impedance path) intermittently closes and opens up the switch, therefore the device may or may not provide protection against future open-circuit cell failure. Further testing with switches F01 and F02 may provide clarification. The formation of a continuous low impedance path (a homogeneous low melting point alloy), has been confirmed - which is the expected mode of operation.

Methods/Labor Standards Application Program - Phase IV

DTIC Science & Technology

1985-01-01

Engine Platform a. Pressure switch b. Compressor motor c. Voltage regulator d. Open and clean generator exciter and main windings S3 . Main Collector...clean motors b. Slip rings Gantry #3 Annual: S2. Engine Platform a. Pressure switch b. Compressor motor Voltage regulator d. Open and clean generator...Travel Motors Open and clean motorsa. b. Slip rings Gantry #4 S2 . S3. S4 . S5 . Engine Platform a. Pressure switch b. Compressor motor Voltage regulator

Multi-gap high impedance plasma opening switch

DOEpatents

Mason, R.J.

1996-10-22

A high impedance plasma opening switch having an anode and a cathode and at least one additional electrode placed between the anode and cathode is disclosed. The presence of the additional electrodes leads to the creation of additional plasma gaps which are in series, increasing the net impedance of the switch. An equivalent effect can be obtained by using two or more conventional plasma switches with their plasma gaps wired in series. Higher impedance switches can provide high current and voltage to higher impedance loads such as plasma radiation sources. 12 figs.

Are Birds Smarter Than Mathematicians? Pigeons (Columba livia) Perform Optimally on a Version of the Monty Hall Dilemma

PubMed Central

Herbranson, Walter T.; Schroeder, Julia

2011-01-01

The “Monty Hall Dilemma” (MHD) is a well known probability puzzle in which a player tries to guess which of three doors conceals a desirable prize. After an initial choice is made, one of the remaining doors is opened, revealing no prize. The player is then given the option of staying with their initial guess or switching to the other unopened door. Most people opt to stay with their initial guess, despite the fact that switching doubles the probability of winning. A series of experiments investigated whether pigeons (Columba livia), like most humans, would fail to maximize their expected winnings in a version of the MHD. Birds completed multiple trials of a standard MHD, with the three response keys in an operant chamber serving as the three doors and access to mixed grain as the prize. Across experiments, the probability of gaining reinforcement for switching and staying was manipulated, and birds adjusted their probability of switching and staying to approximate the optimal strategy. Replication of the procedure with human participants showed that humans failed to adopt optimal strategies, even with extensive training. PMID:20175592

Are birds smarter than mathematicians? Pigeons (Columba livia) perform optimally on a version of the Monty Hall Dilemma.

PubMed

Herbranson, Walter T; Schroeder, Julia

2010-02-01

The "Monty Hall Dilemma" (MHD) is a well known probability puzzle in which a player tries to guess which of three doors conceals a desirable prize. After an initial choice is made, one of the remaining doors is opened, revealing no prize. The player is then given the option of staying with their initial guess or switching to the other unopened door. Most people opt to stay with their initial guess, despite the fact that switching doubles the probability of winning. A series of experiments investigated whether pigeons (Columba livia), like most humans, would fail to maximize their expected winnings in a version of the MHD. Birds completed multiple trials of a standard MHD, with the three response keys in an operant chamber serving as the three doors and access to mixed grain as the prize. Across experiments, the probability of gaining reinforcement for switching and staying was manipulated, and birds adjusted their probability of switching and staying to approximate the optimal strategy. Replication of the procedure with human participants showed that humans failed to adopt optimal strategies, even with extensive training.

49 CFR 236.342 - Switch circuit controller.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Switch circuit controller. 236.342 Section 236.342... Instructions § 236.342 Switch circuit controller. Switch circuit controller connected at the point to switch... corresponding to switch point closure when switch point is open one-fourth inch or more. Inspection and Tests ...

49 CFR 236.342 - Switch circuit controller.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Switch circuit controller. 236.342 Section 236.342... Instructions § 236.342 Switch circuit controller. Switch circuit controller connected at the point to switch... corresponding to switch point closure when switch point is open one-fourth inch or more. Inspection and Tests ...

49 CFR 236.342 - Switch circuit controller.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Switch circuit controller. 236.342 Section 236.342... Instructions § 236.342 Switch circuit controller. Switch circuit controller connected at the point to switch... corresponding to switch point closure when switch point is open one-fourth inch or more. Inspection and Tests ...

49 CFR 236.342 - Switch circuit controller.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Switch circuit controller. 236.342 Section 236.342... Instructions § 236.342 Switch circuit controller. Switch circuit controller connected at the point to switch... corresponding to switch point closure when switch point is open one-fourth inch or more. Inspection and Tests ...

49 CFR 236.342 - Switch circuit controller.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Switch circuit controller. 236.342 Section 236.342... Instructions § 236.342 Switch circuit controller. Switch circuit controller connected at the point to switch... corresponding to switch point closure when switch point is open one-fourth inch or more. Inspection and Tests ...

Trans−cis Switching Mechanisms in Proline Analogues and Their Relevance for the Gating of the 5-HT3 Receptor

PubMed Central

2009-01-01

Trans−cis isomerization of a proline peptide bond is a potential mechanism to open the channel of the 5-HT3 receptor. Here, we have used the metadynamics method to theoretically explore such a mechanism. We have determined the free energy surfaces in aqueous solution of a series of dipeptides of proline analogues and evaluated the free energy difference between the cis and trans isomers. These theoretical results were then compared with data from mutagenesis experiments, in which the response of the 5-HT3 receptor was measured when the proline at the apex of the M2-M3 transmembrane domain loop was mutated. The strong correlation between the experimental and the theoretical data supports the existence of a trans−cis proline switch for opening the 5-HT3 receptor ion channel. PMID:19663504

Trans-cis switching mechanisms in proline analogues and their relevance for the gating of the 5-HT3 receptor.

PubMed

Melis, Claudio; Bussi, Giovanni; Lummis, Sarah C R; Molteni, Carla

2009-09-03

Trans-cis isomerization of a proline peptide bond is a potential mechanism to open the channel of the 5-HT(3) receptor. Here, we have used the metadynamics method to theoretically explore such a mechanism. We have determined the free energy surfaces in aqueous solution of a series of dipeptides of proline analogues and evaluated the free energy difference between the cis and trans isomers. These theoretical results were then compared with data from mutagenesis experiments, in which the response of the 5-HT(3) receptor was measured when the proline at the apex of the M2-M3 transmembrane domain loop was mutated. The strong correlation between the experimental and the theoretical data supports the existence of a trans-cis proline switch for opening the 5-HT(3) receptor ion channel.

Current interruption in inductive storage systems with inertial current source

NASA Astrophysics Data System (ADS)

Vitkovitsky, I. M.; Conte, D.; Ford, R. D.; Lupton, W. H.

1980-03-01

Utilization of inertial current source inductive storage with high power output requires a switch with short opening time. This switch must operate as a circuit breaker, i.e., be capable to carry the current for a time period characteristic of inertial systems, such as homopolar generators. For reasonable efficiency, its opening time must be fast to minimize the energy dissipated in downstream fuse stages required for any additional pulse compression. A switch that satisfies these criteria, as well as other requirements such as that for high voltage operation associated with high power output, is an explosively driven switch consisting of large number of gaps arranged in series. The performance of this switch in limiting and/or interrupting currents produced by large generators has been studied. Single switch modules were designed and tested for limiting the commutating current output of 1 MW, 60 Hz, generator and 500 KJ capacitor banks. Current limiting and commutation were evaluated, using these sources, for currents ranging up to 0.4 MA. The explosive opening of the switch was found to provide an effective first stage for further pulse compression. It opens in tens of microseconds, commutates current at high efficiency ( = 905) recovers very rapidly over a wide range of operating conditions.

Reusable fast opening switch

DOEpatents

Van Devender, J.P.; Emin, D.

1983-12-21

A reusable fast opening switch for transferring energy, in the form of a high power pulse, from an electromagnetic storage device such as an inductor into a load. The switch is efficient, compact, fast and reusable. The switch comprises a ferromagnetic semiconductor which undergoes a fast transition between conductive and metallic states at a critical temperature and which undergoes the transition without a phase change in its crystal structure. A semiconductor such as europium rich europhous oxide, which undergoes a conductor to insulator transition when it is joule heated from its conductor state, can be used to form the switch.

Reusable fast opening switch

DOEpatents

Van Devender, John P.; Emin, David

1986-01-01

A reusable fast opening switch for transferring energy, in the form of a high power pulse, from an electromagnetic storage device such as an inductor into a load. The switch is efficient, compact, fast and reusable. The switch comprises a ferromagnetic semiconductor which undergoes a fast transition between conductive and insulating states at a critical temperature and which undergoes the transition without a phase change in its crystal structure. A semiconductor such as europium rich europhous oxide, which undergoes a conductor to insulator transition when it is joule heated from its conductor state, can be used to form the switch.

Low Power Switching for Antenna Reconfiguration

NASA Technical Reports Server (NTRS)

Bauhahn, Paul E. (Inventor); Becker, Robert C. (Inventor); Meyers, David W. (Inventor); Muldoon, Kelly P. (Inventor)

2008-01-01

Methods and systems for low power switching are provided. In one embodiment, an optical switching system is provided. The system comprises at least one optically controlled switch adapted to maintain one of an open state and a closed state based on an associated light signal; and at least one light source adapted to output the associated light signal to the at least one switch, wherein the at least one light source cycles the light signal on and off, wherein the at least one light source is cycled on for a sufficient duration of time and with a sufficient periodicity to maintain the optically controlled switch in one of an open state and a closed state.

Two terminal micropower radar sensor

DOEpatents

McEwan, Thomas E.

1995-01-01

A simple, low power ultra-wideband radar motion sensor/switch configuration connects a power source and load to ground. The switch is connected to and controlled by the signal output of a radar motion sensor. The power input of the motion sensor is connected to the load through a diode which conducts power to the motion sensor when the switch is open. A storage capacitor or rechargeable battery is connected to the power input of the motion sensor. The storage capacitor or battery is charged when the switch is open and powers the motion sensor when the switch is closed. The motion sensor and switch are connected between the same two terminals between the source/load and ground.

Two terminal micropower radar sensor

DOEpatents

McEwan, T.E.

1995-11-07

A simple, low power ultra-wideband radar motion sensor/switch configuration connects a power source and load to ground. The switch is connected to and controlled by the signal output of a radar motion sensor. The power input of the motion sensor is connected to the load through a diode which conducts power to the motion sensor when the switch is open. A storage capacitor or rechargeable battery is connected to the power input of the motion sensor. The storage capacitor or battery is charged when the switch is open and powers the motion sensor when the switch is closed. The motion sensor and switch are connected between the same two terminals between the source/load and ground. 3 figs.

Transient current interruption mechanism in a magnetically delayed vacuum switch

NASA Technical Reports Server (NTRS)

Morris, Gibson, Jr.; Dougal, Roger A.

1993-01-01

The capacity of a magnetically delayed vacuum switch to conduct current depends on the density of plasma injected into the switch. Exceeding the current capacity results in the switch entering a lossy mode of operation characterized by a transient interruption of the main current (opening behavior) and a rapid increase of voltage across the vacuum gap. Streak and framing photographs of the discharge indicate that a decrease of luminosity near the middle of the gap preceeds the transition to the opening phase. The zone of low luminosity propagates toward the cathode. This evidence suggests that the mechanism causing the opening phase is erosion of the background plasma in a manner similar to that in a plasma-opening switch. The resulting ion depletion forces a space-charge-limited conduction mode. The switch inductance maintains a high discharge current even during the space-charge-limited conduction phase, thus producing high internal fields. The high accelerating voltage, in turn, produces electron and ion beams that heat the electrode surfaces. As a result of the heating, jets of electrode vapor issue from the electrodes, either cathode or anode, depending on the selection of electrode materials.

49 CFR 229.87 - Hand-operated switches.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Hand-operated switches. 229.87 Section 229.87....87 Hand-operated switches. All hand-operated switches carrying currents with a potential of more than... outside of the cover. Means shall be provided to show whether the switches are open or closed. Switches...

49 CFR 229.87 - Hand-operated switches.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Hand-operated switches. 229.87 Section 229.87....87 Hand-operated switches. All hand-operated switches carrying currents with a potential of more than... outside of the cover. Means shall be provided to show whether the switches are open or closed. Switches...

49 CFR 229.87 - Hand-operated switches.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Hand-operated switches. 229.87 Section 229.87....87 Hand-operated switches. All hand-operated switches carrying currents with a potential of more than... outside of the cover. Means shall be provided to show whether the switches are open or closed. Switches...

49 CFR 229.87 - Hand-operated switches.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Hand-operated switches. 229.87 Section 229.87....87 Hand-operated switches. All hand-operated switches carrying currents with a potential of more than... outside of the cover. Means shall be provided to show whether the switches are open or closed. Switches...

Conditions for Stabilizability of Linear Switched Systems

NASA Astrophysics Data System (ADS)

Minh, Vu Trieu

2011-06-01

This paper investigates some conditions that can provide stabilizability for linear switched systems with polytopic uncertainties via their closed loop linear quadratic state feedback regulator. The closed loop switched systems can stabilize unstable open loop systems or stable open loop systems but in which there is no solution for a common Lyapunov matrix. For continuous time switched linear systems, we show that if there exists solution in an associated Riccati equation for the closed loop systems sharing one common Lyapunov matrix, the switched linear systems are stable. For the discrete time switched systems, we derive a Linear Matrix Inequality (LMI) to calculate a common Lyapunov matrix and solution for the stable closed loop feedback systems. These closed loop linear quadratic state feedback regulators guarantee the global asymptotical stability for any switched linear systems with any switching signal sequence.

Investigation of a high power electromagnetic pulse source.

PubMed

Wang, Yuwei; Chen, Dongqun; Zhang, Jiande; Cao, Shengguang; Li, Da; Liu, Chebo

2012-09-01

A high power electromagnetic pulse source with a resonant antenna driven by a compact power supply was investigated in this paper. To match the impedance of the resonant antenna and initial power source, a compact power conditioning circuit based on electro exploding opening switch (EEOS) and pulsed transformer was adopted. In the preliminary experiments, an impulse capacitor was used to drive the system. With the opening of the EEOS at the current of 15 kA flowing trough the primary of the transformer, the resonant antenna was rapidly charged to about -370 kV within a time of about 100 ns. When the switch in the resonant antenna closed at the charging voltage of about -202 kV, the peak intensity of the detected electric field at a distance of about 10 m from the center of the source was 7.2 kV∕m. The corresponding peak power of the radiated electromagnetic field reached 76 MW, while the total radiated electromagnetic energy was about 0.65 J. The total energy efficiency of the resonant antenna was about 22% which can be improved by increasing the closing rapidity of the switch in the antenna.

Illuminated push-button switch

NASA Technical Reports Server (NTRS)

Iwagiri, T.

1983-01-01

An illuminated push-button switch is described. It is characterized by the fact that is consists of a switch group, an operator button opening and closing the switch group, and a light-emitting element which illuminates the face of the operator button.

A fault-tolerant strategy based on SMC for current-controlled converters

NASA Astrophysics Data System (ADS)

Azer, Peter M.; Marei, Mostafa I.; Sattar, Ahmed A.

2018-05-01

The sliding mode control (SMC) is used to control variable structure systems such as power electronics converters. This paper presents a fault-tolerant strategy based on the SMC for current-controlled AC-DC converters. The proposed SMC is based on three sliding surfaces for the three legs of the AC-DC converter. Two sliding surfaces are assigned to control the phase currents since the input three-phase currents are balanced. Hence, the third sliding surface is considered as an extra degree of freedom which is utilised to control the neutral voltage. This action is utilised to enhance the performance of the converter during open-switch faults. The proposed fault-tolerant strategy is based on allocating the sliding surface of the faulty leg to control the neutral voltage. Consequently, the current waveform is improved. The behaviour of the current-controlled converter during different types of open-switch faults is analysed. Double switch faults include three cases: two upper switch fault; upper and lower switch fault at different legs; and two switches of the same leg. The dynamic performance of the proposed system is evaluated during healthy and open-switch fault operations. Simulation results exhibit the various merits of the proposed SMC-based fault-tolerant strategy.

Reversing-counterpulse repetitive-pulse inductive storage circuit

DOEpatents

Honig, Emanuel M.

1987-01-01

A high-power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime.

Reversing-counterpulse repetitive-pulse inductive storage circuit

DOEpatents

Honig, E.M.

1984-06-05

A high power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime.

Advances in Explosively Formed Fuse Opening Switches

DTIC Science & Technology

1987-06-01

ADVANCES IN EXPLOSIVELY FORMED FUSE OPENING SWITCHES* J. H. Goforth, R. S. Caird, A. E. Greene, I. R. Lindemuth, S. P. Marsh, H. Oona, and R. E...conductor into a series of thin sections. Augmented by an undetermined amount of heating due to the extrusion process, Joule heating in the thin...with initial field fed directly into the generator by a capacitor bank. As described in Ref. 2, these tests demonstrated that the switch would

49 CFR 236.207 - Electric lock on hand-operated switch; control.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Electric lock on hand-operated switch; control... switch; control. Electric lock on hand-operated switch shall be controlled so that it cannot be unlocked until control circuits of signals governing movements over such switch have been opened. Approach or...

49 CFR 236.207 - Electric lock on hand-operated switch; control.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Electric lock on hand-operated switch; control... switch; control. Electric lock on hand-operated switch shall be controlled so that it cannot be unlocked until control circuits of signals governing movements over such switch have been opened. Approach or...

49 CFR 236.207 - Electric lock on hand-operated switch; control.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Electric lock on hand-operated switch; control... switch; control. Electric lock on hand-operated switch shall be controlled so that it cannot be unlocked until control circuits of signals governing movements over such switch have been opened. Approach or...

49 CFR 236.732 - Controller, circuit; switch.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 4 2013-10-01 2013-10-01 false Controller, circuit; switch. 236.732 Section 236... § 236.732 Controller, circuit; switch. A device for opening and closing electric circuits, operated by a rod connected to a switch, derail or movable-point frog. ...

49 CFR 236.732 - Controller, circuit; switch.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Controller, circuit; switch. 236.732 Section 236... § 236.732 Controller, circuit; switch. A device for opening and closing electric circuits, operated by a rod connected to a switch, derail or movable-point frog. ...

49 CFR 236.732 - Controller, circuit; switch.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 4 2014-10-01 2014-10-01 false Controller, circuit; switch. 236.732 Section 236... § 236.732 Controller, circuit; switch. A device for opening and closing electric circuits, operated by a rod connected to a switch, derail or movable-point frog. ...

49 CFR 236.732 - Controller, circuit; switch.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Controller, circuit; switch. 236.732 Section 236... § 236.732 Controller, circuit; switch. A device for opening and closing electric circuits, operated by a rod connected to a switch, derail or movable-point frog. ...

Switching from adalimumab to tofacitinib in the treatment of patients with rheumatoid arthritis.

PubMed

Genovese, Mark C; van Vollenhoven, Ronald F; Wilkinson, Bethanie; Wang, Lisy; Zwillich, Samuel H; Gruben, David; Biswas, Pinaki; Riese, Richard; Takiya, Liza; Jones, Thomas V

2016-06-23

Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA). The aim of this study was to explore the safety and efficacy of open-label tofacitinib following blinded treatment with adalimumab or tofacitinib for moderate to severe RA. Analyses included patients treated with adalimumab 40 mg once every 2 weeks or tofacitinib 10 mg twice daily (BID) with background methotrexate (MTX) in a 12-month randomized study (NCT00853385), who subsequently received tofacitinib 10 mg BID (with/without background MTX) in an open-label extension (NCT00413699). Patients with treatment-related serious adverse events (AEs) and serious or recurrent infections in the index study were excluded from the extension study. Exposure-adjusted incidence rates of safety-related events were assessed in 3-month and 12-month periods in the year before and in the year after switching. Efficacy was assessed 3 months before, at the time of, and 3 months after switching. There were 233 (107 adalimumab to tofacitinib 10 mg BID, 126 blinded to open-label tofacitinib 10 mg BID) patients included in these analyses. Patients in both treatment sequences had similar incidence rates (per 100 patient-years) of discontinuation due to AEs, serious AEs, and serious infections in the year before and in the year after switching. Incidence rates of AEs were increased in the first 3 months after switching compared with the last 3 months before switching in both treatment groups. Switching from either blinded adalimumab or tofacitinib to open-label tofacitinib resulted in numerically higher incidence of responders for signs and symptoms of disease and improved physical function. Treatment can be directly switched from adalimumab to tofacitinib. A similar safety and efficacy profile was seen when patients received open-label tofacitinib after receiving either blinded adalimumab or tofacitinib. ClinicalTrials.gov Identifiers: NCT00853385 , registered 27 February 2009; NCT00413699 , registered 18 December 2006.

Staghorn: An Automated Large-Scale Distributed System Analysis Platform

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gabert, Kasimir; Burns, Ian; Elliott, Steven

2016-09-01

Conducting experiments on large-scale distributed computing systems is becoming significantly easier with the assistance of emulation. Researchers can now create a model of a distributed computing environment and then generate a virtual, laboratory copy of the entire system composed of potentially thousands of virtual machines, switches, and software. The use of real software, running at clock rate in full virtual machines, allows experiments to produce meaningful results without necessitating a full understanding of all model components. However, the ability to inspect and modify elements within these models is bound by the limitation that such modifications must compete with the model,more » either running in or alongside it. This inhibits entire classes of analyses from being conducted upon these models. We developed a mechanism to snapshot an entire emulation-based model as it is running. This allows us to \\freeze time" and subsequently fork execution, replay execution, modify arbitrary parts of the model, or deeply explore the model. This snapshot includes capturing packets in transit and other input/output state along with the running virtual machines. We were able to build this system in Linux using Open vSwitch and Kernel Virtual Machines on top of Sandia's emulation platform Firewheel. This primitive opens the door to numerous subsequent analyses on models, including state space exploration, debugging distributed systems, performance optimizations, improved training environments, and improved experiment repeatability.« less

Series-counterpulse repetitive-pulse inductive storage circuit

DOEpatents

Honig, Emanuel M.

1986-01-01

A high-power series-counterpulse repetitive-pulse inductive energy storage and transfer circuit includes an opening switch, a main energy storage coil, and a counterpulse capacitor. The load pulse is initiated simultaneously with the initiation of the counterpulse which is used to turn the opening switch off. There is no delay from command to output pulse. During the load pulse, the counterpulse capacitor is first discharged and then recharged in the opposite polarity with sufficient energy to accomplish the load counterpulse which terminates the load pulse and turns the load switch off. When the main opening switch is triggered closed again to terminate the load pulse, the counterpulse capacitor discharges in the reverse direction through the load switch and through the load, causing a rapid, sharp cutoff of the load pulse as well as recovering any energy remaining in the load inductance. The counterpulse capacitor is recharged to its original condition by the main energy storage coil after the load pulse is over, not before it begins.

A coaxial radial opening switch for a distributed-energy-store rail launcher

NASA Astrophysics Data System (ADS)

Upshaw, J. L.; Zowarka, R. C.

1984-03-01

The design, fabrication, and initial testing results for a coaxial radial opening switch for a distributed-energy-store rail launcher are presented. In this nonarcing switch, the voltage needed to transfer current to the rail launcher is generated in a fixed resistor sized to absorb the energy required to accomplish the switching. The coaxial geometry consisting of concentric rings allowed flexibility in defining the conductive and resistive portions of the switch, and also provided tight coupling by minimizing the inductance of the current path between the charging path and the load path to minimize the energy absorption requirements. The resistive portion of the switch is composed of a series of stacked circular steel ring laminations. Switching is completed in three intervals through radial actuation. The switch parts were machined from ETP 110 electrical tough pitch copper plate, 2000 series aluminum plate, and close-tolerance standed GFR epoxy. Current may be transferred at levels less than 20 kA.

High frequency switched-mode stimulation can evoke post synaptic responses in cerebellar principal neurons

PubMed Central

van Dongen, Marijn N.; Hoebeek, Freek E.; Koekkoek, S. K. E.; De Zeeuw, Chris I.; Serdijn, Wouter A.

2015-01-01

This paper investigates the efficacy of high frequency switched-mode neural stimulation. Instead of using a constant stimulation amplitude, the stimulus is switched on and off repeatedly with a high frequency (up to 100 kHz) duty cycled signal. By means of tissue modeling that includes the dynamic properties of both the tissue material as well as the axon membrane, it is first shown that switched-mode stimulation depolarizes the cell membrane in a similar way as classical constant amplitude stimulation. These findings are subsequently verified using in vitro experiments in which the response of a Purkinje cell is measured due to a stimulation signal in the molecular layer of the cerebellum of a mouse. For this purpose a stimulator circuit is developed that is able to produce a monophasic high frequency switched-mode stimulation signal. The results confirm the modeling by showing that switched-mode stimulation is able to induce similar responses in the Purkinje cell as classical stimulation using a constant current source. This conclusion opens up possibilities for novel stimulation designs that can improve the performance of the stimulator circuitry. Care has to be taken to avoid losses in the system due to the higher operating frequency. PMID:25798105

HPG operating experience at CEM-UT

NASA Astrophysics Data System (ADS)

Gully, J. H.; Aanstoos, T. A.; Nalty, K.; Walls, W. A.

1986-11-01

Design and functional features are presented for three homopolar generators (HPG) used in experiments during the last decade at the Center for Electromechanics at the University of Texas. The first, a disk-type, 10 MJ HPG, was built in 1973 as a prototype power source for fusion experiments. A second, compact HPG was built in 1980 for opening switch experiments as part of railgun research. The third device is an iron-core, full-scale, high speed bearing and brush test facility for supplying an energy density of 60 MJ/cu m. Engineering data obtained during studies of armature reactions actively cooled brushes morganite-copper graphite rim brushes, and peak currents, are summarized.

Design of Electron-Beam Controlled Switches.

DTIC Science & Technology

1982-11-24

I- HYBRID (OPENING/CLOSING) LO LSW E EBCS(O) 11111 C ESCS(C) T TJL (a) !z 0 TIME E OPEN I IM 0 TIM Fig. 2 - Circuit diagram illustrating the...34 l i iN l II -ItB "i ’ : i = i . • ’ " -.. ~...2 .. .. . * INDUCTIVE (OPENING) (a)(a) LO LSW , io E EBCS(O) III1t RL ___T (a) "ii’ (b) ) IJ.: z 0...switch pressure is given by Eq. (28) with EJ - 20 kV/cm, f. - 2 x lOs cm/V-s for N2-0 2 and ko - 0.25 (Eq. (26)): P -1700 Torr 2.3 atm. (33) The switch

Transient-Switch-Signal Suppressor

NASA Technical Reports Server (NTRS)

Bozeman, Richard J., Jr.

1995-01-01

Circuit delays transmission of switch-opening or switch-closing signal until after preset suppression time. Used to prevent transmission of undesired momentary switch signal. Basic mode of operation simple. Beginning of switch signal initiates timing sequence. If switch signal persists after preset suppression time, circuit transmits switch signal to external circuitry. If switch signal no longer present after suppression time, switch signal deemed transient, and circuit does not pass signal on to external circuitry, as though no transient switch signal. Suppression time preset at value large enough to allow for damping of underlying pressure wave or other mechanical transient.

Research in pulsed power plasma physics

NASA Astrophysics Data System (ADS)

Hinshelwood, David; Rose, David

1993-11-01

The research was conducted in support of light-ion-driven inertial confinement fusion (ICF) for the Department of Energy (DOE), and nuclear weapon effects simulation (NWES) for the Defense Nuclear Agency (DNA). Accomplishments related to ion beams include: development of a practical backup approach to ion beam transport; the first studies of ion-beam interaction with a neutral gas; initial investigations of a promising industrial application of ion beam technology; and detailed theoretical evaluation of several different ion beam transport schemes. Major accomplishments relating to opening switches include: the first direct measurement of the electron density in an opening switch; detailed studies of switch conduction-time scaling; evaluation of several different switch plasma sources; and extensive studies of switch performance into diode loads, leading to the development of a new (and now generally accepted) model of switch behavior.

Mechanism of the Exchange Reaction in HRAS from Multiscale Modeling

PubMed Central

Kapoor, Abhijeet; Travesset, Alex

2014-01-01

HRAS regulates cell growth promoting signaling processes by cycling between active (GTP-bound) and inactive (GDP-bound) states. Understanding the transition mechanism is central for the design of small molecules to inhibit the formation of RAS-driven tumors. Using a multiscale approach involving coarse-grained (CG) simulations, all-atom classical molecular dynamics (CMD; total of 3.02 µs), and steered molecular dynamics (SMD) in combination with Principal Component Analysis (PCA), we identified the structural features that determine the nucleotide (GDP) exchange reaction. We show that weakening the coupling between the SwitchI (residues 25–40) and SwitchII (residues 59–75) accelerates the opening of SwitchI; however, an open conformation of SwitchI is unstable in the absence of guanine nucleotide exchange factors (GEFs) and rises up towards the bound nucleotide to close the nucleotide pocket. Both I21 and Y32, play a crucial role in SwitchI transition. We show that an open SwitchI conformation is not necessary for GDP destabilization but is required for GDP/Mg escape from the HRAS. Further, we present the first simulation study showing displacement of GDP/Mg away from the nucleotide pocket. Both SwitchI and SwitchII, delays the escape of displaced GDP/Mg in the absence of GEF. Based on these results, a model for the mechanism of GEF in accelerating the exchange process is hypothesized. PMID:25272152

Second-Order Nonlinear Optical Properties of a Dithienylethene-Indolinooxazolidine Hybrid: A Joint Experimental and Theoretical Investigation.

PubMed

Bondu, Flavie; Quertinmont, Jean; Rodriguez, Vincent; Pozzo, Jean-Luc; Plaquet, Aurélie; Champagne, Benoît; Castet, Frédéric

2015-12-14

The nonlinear optical (NLO) properties of a double photochrome molecular switch are reported for the first time by considering the four trans forms of a dithienylethene-indolinooxazolidine hybrid. The four forms are characterized by means of hyper-Rayleigh scattering (HRS) experiments and quantum chemical calculations. Experimental measurements provide evidence that the pH- and light-triggered transformations between the different forms of the hybrid are accompanied by large variations of the first hyperpolarizability, which makes this compound an effective multistate NLO switch. Quantum chemical calculations conducted at the time-dependent Hartree-Fock and time-dependent DFT levels agree with the experimental data and allow a complete rationalization of the NLO responses of the different forms. The HRS signal of the forms with an open indolinooxazolidine moiety are more than one order of magnitude larger than that measured for the other forms, whereas the open/closed status of the dithienylethene subunit barely influences the dynamic NLO properties. However, extrapolation of the NLO responses to the static limit leads to univocally distinguishable intrinsic responses for three of the various forms. This hybrid system thus acts as a highly efficient multistate NLO switch for eventual exploitation in optical memory systems with multiple storage and nondestructive readout capacity. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Water SWITCH-ON Spatial Information Platform (SIP)

NASA Astrophysics Data System (ADS)

Sala Calero, J., Sr.; Boot, G., Sr.; Dihé, P., Sr.; Arheimer, B.

2017-12-01

The amount of hydrological open data is continually growing and providing opportunities to the scientific community. Although the existing data portals (GEOSS Portal, INSPIRE community geoportal and others) enable access to open data, many users still find browsing through them difficult. Moreover, the time spent on gathering and preparing data usually is more significant than the time spent on the experiment itself. Thus, any improvement on searching, understanding, accessing or using open data is greatly beneficial. The Spatial Information Platform (SIP) has been developed to tackle these issues within the SWITCH-ON European Commission funded FP7 project. The SIP has been designed as a set of tools based on open standards that provide to the user all the necessary functionalities as described in the Publish-Find-Bind (PFB) pattern. In other words, this means that the SIP helps users to locate relevant and suitable data for their experiments analysis, to access and transform it (filtering, extraction, selection, conversion, aggregation). Moreover, the SIP can be used to provide descriptive information about the data and to publish it so others can find and use it. The SIP is based on existing open data protocols such as the OGC/CSW, OGC/WMS, OpenDAP and open-source components like PostgreSQL/PostGIS, GeoServer and pyCSW. The SIP is divided in three main user interfaces: the BYOD (Browse your open dataset) web interface, the Expert GUI tool and the Upload Data and Metadata web interface. The BYOD HTML5 client is the main entry point for users that want to browse through open data in the SIP. The BYOD has a map interface based on Leaflet JavaScript libraries so that the users can search more efficiently. The web-based Open Data Registration Tool is a user-friendly upload and metadata description interface (geographical extent, license, DOI generation). The Expert GUI is a desktop application that provides full metadata editing capabilities for the metadata moderators of the project. In conclusion, the Spatial Information Platform (SIP) provides to its community a set of tools for better understanding and ease of use of hydrological open-data. Moreover, the SIP has been based on well-known OGC standards that will allow the connection and data harvesting from popular open data portals such as the GEOSS system of systems.

Tri-state logic circuit

NASA Technical Reports Server (NTRS)

Pryor, Richard Lee (Inventor)

1977-01-01

A line driver including a pair of complementary transistors having their conduction paths serially connected between an operating and a reference potential and their bases connected through a first switch to a signal input terminal. A second switch is connected between the common base connection and the common connection of the conduction paths. With the second switch open and the first closed, an output voltage, responsive to the input signal, corresponding to first or second binary values is obtained. When the second switch is closed and the first opened, the transistor pair is turned off, disconnecting the line driver from its load, thereby providing tri-state logic operation.

Reversing-counterpulse repetitive-pulse inductive storage circuit

DOEpatents

Honig, E.M.

1987-02-10

A high-power reversing-counterpulse repetitive-pulse inductive storage and transfer circuit includes an opening switch, a main energy storage coil, a counterpulse capacitor and a small inductor. After counterpulsing the opening switch off, the counterpulse capacitor is recharged by the main energy storage coil before the load pulse is initiated. This gives the counterpulse capacitor sufficient energy for the next counterpulse operation, although the polarity of the capacitor's voltage must be reversed before that can occur. By using a current-zero switch as the counterpulse start switch, the capacitor is disconnected from the circuit (with a full charge) when the load pulse is initiated, preventing the capacitor from depleting its energy store by discharging through the load. After the load pulse is terminated by reclosing the main opening switch, the polarity of the counterpulse capacitor voltage is reversed by discharging the capacitor through a small inductor and interrupting the discharge current oscillation at zero current and peak reversed voltage. The circuit enables high-power, high-repetition-rate operation with reusable switches and features total control (pulse-to-pulse) over output pulse initiation, duration, repetition rate, and, to some extent, risetime. 10 figs.

Series-counterpulse repetitive-pulse inductive storage circuit

DOEpatents

Honig, E.M.

1984-06-05

A high-power series-counterpulse repetitive-pulse inductive energy storage and transfer circuit includes an opening switch, a main energy storage coil, and a counterpulse capacitor. The local pulse is initiated simultaneously with the initiation of the counterpulse used to turn the opening switch off. There is no delay from command to output pulse. During the load pulse, the counterpulse capacitor is automatically charged with sufficient energy to accomplish the load counterpulse which terminates the load pulse and turns the load switch off. When the main opening switch is reclosed to terminate the load pulse, the counterpulse capacitor discharges through the load, causing a rapid, sharp cutoff of the load pulse as well as recovering any energy remaining in the load inductance. The counterpulse capacitor is recharged to its original condition by the main energy storage coil after the load pulse is over, not before it begins.

Long-Term Memory and the Control of Attentional Control

PubMed Central

Mayr, Ulrich; Kuhns, David; Hubbard, Jason

2014-01-01

Task-switch costs and in particular the switch-cost asymmetry (i.e., the larger costs of switching to a dominant than a non-dominant task) are usually explained in terms of trial-to-trial carry-over of task-specific control settings. Here we argue that task switches are just one example of situations that trigger a transition from working-memory maintenance to updating, thereby opening working memory to interference from long-term memory. We used a new paradigm that requires selecting a spatial location either on the basis of a central cue (i.e., endogenous control of attention) or a peripheral, sudden onset (i.e., exogenous control of attention). We found a strong cost asymmetry that occurred even after short interruptions of otherwise single-task blocks (Exp. 1-3), but that was much stronger when participants had experienced the competing task under conditions of conflict (Exp. 1-2). Experiment 3 showed that the asymmetric costs were due to interruptions per se, rather than to associative interference tied to specific interruption activities. Experiment 4 generalized the basic pattern across interruptions varying in length or control demands and Experiment 5 across primary tasks with response-selection conflict rather than attentional conflict. Combined, the results support a model in which costs of selecting control settings arise when (a) potentially interfering memory traces have been encoded in long-term memory and (b) working-memory is forced from a maintenance mode into an updating mode (e.g., through task interruptions), thereby allowing unwanted retrieval of the encoded memory traces. PMID:24650696

Current Interruption and Particle Beam Generation by a Plasma Focus.

DTIC Science & Technology

1982-11-30

Through collaboration with Dr. K. H. Schoenbach of Texas Tech University the plasma focus opening switch (PFOS) was revised to answer basic questions...results are consistent with the snowplow model. The final analysis of the plasma focus particle beam generation experiments was completed and a...strong correlation was found for the beam-target model as the mechanism for neutron production in the Illinois plasma focus device. (Author)

A multistate pH-triggered nonlinear optical switch.

PubMed

Castet, Frédéric; Champagne, Benoît; Pina, Fernando; Rodriguez, Vincent

2014-08-04

By using hyper-Rayleigh scattering experiments and quantum-chemical calculations, we demonstrate that nonlinear optics can be used to probe unequivocally, within a non-destructive process, the multiple electronic states that are activated upon pH- and light-triggered transformations of the 4'-hydroxyflavylium ion. These results open new perspectives in the design of molecular-scale high-density optical memory. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Sharing Water-related Information to Tackle Changes in the Hydrosphere - for Operational Needs (SWITCH-ON)

NASA Astrophysics Data System (ADS)

Arheimer, Berit

2015-04-01

Recently, a collaborative EU project started called SWITCH-ON (EU FP7 project No 603587) coordinated by SMHI to support the INSPIRE directive and the Open Data Strategy. The overall goal of the project is to establish a "one-stop-shop" web portal for easy access to European water information. The project will use open data, provide infrastructure for sharing and collaboration, and add value to society and research by repurposing and refining data from various sources. The SWITCH-ON project http://www.water-switch-on.eu/ will establish new forms of water research and facilitate the development of new products and services based on principles of sharing and community building in the water society. The SWITCH-ON objectives are to use open data for implementing: 1) an innovative spatial information platform (SIP) to find, bind, transform and publish data, 2) entirely new forms of collaborative research organised in a Virtual Water-Science Laboratory, open for any research group, 3) fourteen new operational products for water management and awareness, 4) outreach facilities for new water business and knowledge in line with the Europe's smart growth and environmental objectives. This poster will describe the overall project goals and especially the recent progress on developing a Virtual Water-Science Laboratory. Contact: waterswitchon@gmail.com

Access control mechanism of wireless gateway based on open flow

NASA Astrophysics Data System (ADS)

Peng, Rong; Ding, Lei

2017-08-01

In order to realize the access control of wireless gateway and improve the access control of wireless gateway devices, an access control mechanism of SDN architecture which is based on Open vSwitch is proposed. The mechanism utilizes the features of the controller--centralized control and programmable. Controller send access control flow table based on the business logic. Open vSwitch helps achieve a specific access control strategy based on the flow table.

Simulation and Analysis of Electric Field for the Disconnector Switch Incomplete Opening Position Based on 220kV GIS

NASA Astrophysics Data System (ADS)

Wang, Feifeng; Huang, Huimin; Su, Yi; Yan, Dandan; Lu, Yufeng; Xia, Xiaofei; Yang, Jian

2018-05-01

It has accounted for a large proportion of GIS equipment defects, which cause the disconnector switches to incomplete open-close position. Once opening operation is not in place, it will arouse continuous arcing between contacts to reduce insulation strength. Otherwise, the intense heat give rise to burn the contact, which has a severe effect on the safe operation of power grid. This paper analyzes some typical defection cases about the opening operation incomplete for disconnector switches of GIS. The COMSOL Multiphysics is applied to verify the influence on electric field distribution. The results show that moving contact out shield is 20 mm, the electric field distribution of the moving contact surface is uneven, and the maximum electric field value can reach 9.74 kV/mm.

A dual switch controls bacterial enhancer-dependent transcription

PubMed Central

Wiesler, Simone C.; Burrows, Patricia C.; Buck, Martin

2012-01-01

Bacterial RNA polymerases (RNAPs) are targets for antibiotics. Myxopyronin binds to the RNAP switch regions to block structural rearrangements needed for formation of open promoter complexes. Bacterial RNAPs containing the major variant σ54 factor are activated by enhancer-binding proteins (bEBPs) and transcribe genes whose products are needed in pathogenicity and stress responses. We show that (i) enhancer-dependent RNAPs help Escherichia coli to survive in the presence of myxopyronin, (ii) enhancer-dependent RNAPs partially resist inhibition by myxopyronin and (iii) ATP hydrolysis catalysed by bEBPs is obligatory for functional interaction of the RNAP switch regions with the transcription start site. We demonstrate that enhancer-dependent promoters contain two barriers to full DNA opening, allowing tight regulation of transcription initiation. bEBPs engage in a dual switch to (i) allow propagation of nucleated DNA melting from an upstream DNA fork junction and (ii) complete the formation of the transcription bubble and downstream DNA fork junction at the RNA synthesis start site, resulting in switch region-dependent RNAP clamp closure and open promoter complex formation. PMID:22965125

Polymer thick-film conductors and dielectrics for membrane switches and flexible circuitry

NASA Technical Reports Server (NTRS)

Nazarenko, N.

1983-01-01

The fabrication and operation of membrane switches are discussed. The membrane switch functions as a normally open, momentary contact, low-voltage pressure-sensitive device. Its design is a three-layer sandwich usually constructed of polyester film. Conductive patterns are deposited onto the inner side of top and bottom sheets by silk screening. The center spacer is then placed between the two circuit layers to form a sandwich, generally held together by an adhesive. When pressure is applied to the top layer, it flexes through the punched openings of the spacer to establish electrical contact between conductive pads of the upper and lower sheets, momentarily closing the circuit. Upon release of force the top sheet springs back to its normal open position. The membrane touch switch is being used in a rapidly expanding range of applications, including instrumentation, appliances, electronic games and keyboards. Its board acceptance results from its low cost, durability, ease of manufacture, cosmetic appeal and design flexibility. The principal electronic components in the membrane switch are the conductor and dielectric.

Advanced Technical Data Study

DTIC Science & Technology

1975-01-29

will shut down automatically when condenser high pressure causes Pressure Limit Control high pressure switch to release. Press START switch (3...power cable (1) from facility pow- er. Troubleshoot cooling unit, for HI-LOW pressure switch repeated cutout. Refer to AGE ECU Cooling Unit...acti- vate when loss of air flow oc- curred, the pressure switch (3) failed to open circuit. Adjust or replace pressure switch . Refer to

Switch wear leveling

DOEpatents

Wu, Hunter; Sealy, Kylee; Gilchrist, Aaron

2015-09-01

An apparatus for switch wear leveling includes a switching module that controls switching for two or more pairs of switches in a switching power converter. The switching module controls switches based on a duty cycle control technique and closes and opens each switch in a switching sequence. The pairs of switches connect to a positive and negative terminal of a DC voltage source. For a first switching sequence a first switch of a pair of switches has a higher switching power loss than a second switch of the pair of switches. The apparatus includes a switch rotation module that changes the switching sequence of the two or more pairs of switches from the first switching sequence to a second switching sequence. The second switch of a pair of switches has a higher switching power loss than the first switch of the pair of switches during the second switching sequence.

From inflammation to wound healing: using a simple model to understand the functional versatility of murine macrophages.

PubMed

Childs, Lauren M; Paskow, Michael; Morris, Sidney M; Hesse, Matthias; Strogatz, Steven

2011-11-01

Macrophages are fundamental cells of the innate immune system. Their activation is essential for such distinct immune functions as inflammation (pathogen-killing) and tissue repair (wound healing). An open question has been the functional stability of an individual macrophage cell: whether it can change its functional profile between different immune responses such as between the repair pathway and the inflammatory pathway. We studied this question theoretically by constructing a rate equation model for the key substrate, enzymes and products of the pathways; we then tested the model experimentally. Both our model and experiments show that individual macrophages can switch from the repair pathway to the inflammation pathway but that the reverse switch does not occur.

From Inflammation to Wound Healing: Using a Simple Model to Understand the Functional Versatility of Murine Macrophages

PubMed Central

Paskow, Michael; Morris, Sidney M.; Hesse, Matthias; Strogatz, Steven

2011-01-01

Macrophages are fundamental cells of the innate immune system. Their activation is essential for such distinct immune functions as inflammation (pathogen-killing) and tissue repair (wound healing). An open question has been the functional stability of an individual macrophage cell: whether it can change its functional profile between different immune responses such as between the repair pathway and the inflammatory pathway. We studied this question theoretically by constructing a rate equation model for the key substrate, enzymes and products of the pathways; we then tested the model experimentally. Both our model and experiments show that individual macrophages can switch from the repair pathway to the inflammation pathway but that the reverse switch does not occur. PMID:21347813

An open-closed-loop iterative learning control approach for nonlinear switched systems with application to freeway traffic control

NASA Astrophysics Data System (ADS)

Sun, Shu-Ting; Li, Xiao-Dong; Zhong, Ren-Xin

2017-10-01

For nonlinear switched discrete-time systems with input constraints, this paper presents an open-closed-loop iterative learning control (ILC) approach, which includes a feedforward ILC part and a feedback control part. Under a given switching rule, the mathematical induction is used to prove the convergence of ILC tracking error in each subsystem. It is demonstrated that the convergence of ILC tracking error is dependent on the feedforward control gain, but the feedback control can speed up the convergence process of ILC by a suitable selection of feedback control gain. A switched freeway traffic system is used to illustrate the effectiveness of the proposed ILC law.

A Josephson Junction based SPDT switch

NASA Astrophysics Data System (ADS)

Zhang, Helin; Earnest, Nathan; Lu, Yao; Ma, Ruichao; Chakram, Srivatsan; Schuster, David

RF microwave switches are useful tools in cryogenic experiments, allowing for multiple experiments to be connected to a single cryogenic measurement chain. However, these switches dissipate a substantial amount of heat, preventing fast switching. Josephson junction (JJ) are a promising avenue for realizing millikelvin microwave switching. We present a JJ based single-pole-double throw (SPDT) switch that has fast switching time, no heat dissipation, large on/off contrast, and works over a wide bandwidth. The switch can be used for real-time switching between experiments, routing single photons, or even generating entanglement. We will describe the design of the switch and present experimental characterization of its performance.

49 CFR 236.732 - Controller, circuit; switch.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Controller, circuit; switch. 236.732 Section 236.732 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... § 236.732 Controller, circuit; switch. A device for opening and closing electric circuits, operated by a...

Evaluating intraocular pressure-lowering solutions for the treatment of open-angle glaucoma: comparison between bimatoprost 0.03% and bimatoprost 0.01% - an observational switch study.

PubMed

Deshpande, Sarita S; Sonty, Sriram; Ahmad, Afzal

2017-01-01

The purpose of this study is to evaluate the intraocular pressure (IOP)-lowering efficacy of bimatoprost 0.01% solution in patients with primary open-angle glaucoma (POAG), who were switched from bimatoprost 0.03% solution, compared to patients with POAG who continued on bimatoprost 0.03% solution. A retrospective review evaluated 35 patients (35 right eyes [OD], 34 left eyes [OS]) who remained on bimatoprost 0.03% and 30 patients (27 OD, 30 OS) who were switched to bimatoprost 0.01% during the period January 8, 2010 to December 26, 2012. Mean IOP was measured 6 and 3 months before the switch, at switch, and 3, 6, and 12 months after the switch. Hyperemia scores were recorded before and after the switch and were compared to a picture scale. Mean IOP in the group that switched was 16.96±5.03 mmHg in OD and 17.67±5.33 mmHg in OS at baseline. Mean IOP postswitch to bimatoprost 0.01% solution was 17.60±4.34 mmHg in OD and 17.00±3.37 mmHg in OS. IOP was not significantly reduced in either OD or OS postswitch to bimatoprost 0.01% ( P 1 =0.5 OD, P 2 =0.2 OS). The hyperemia scores improved remarkably when bimatoprost 0.03% solution was switched to bimatoprost 0.01% solution ( P <0.001). To our knowledge, this is the first switch study evaluating the hypotensive efficacy and tolerability of bimatoprost in a group of patients with open-angle glaucoma. In this study comparing bimatoprost 0.03% and 0.01% solution, we found improved tolerability postswitch to 0.01% from 0.03% bimatoprost, similar efficacy between the two concentrations before and after switch in the same patient population, and similar IOPs comparable to nonswitch bimatoprost 0.03% solution.

The preparation effect in task switching: carryover of SOA.

PubMed

Altmann, Erik M

2004-01-01

A common finding in task-switching studies is switch preparation (commonly known as the preparation effect), in which a longer interval between task cue and trial stimulus (i.e., a longer stimulus onset asynchrony, or SOA) reduces the cost of switching to a different task. Three experiments link switch preparation to within-subjects manipulations of SOA. In Experiment 1, SOA was randomized within subjects, producing switch preparation that was more pronounced when the SOA switched from the previous trial than when the SOA repeated. In Experiment 2, SOA was blocked within subjects, producing switch preparation but not on the first block of trials. In Experiment 3, SOA was manipulated between subjects with sufficient statistical power to detect switch preparation, but the effect was absent. The results favor an encoding view of cognitive control, but show that any putative switching mechanism reacts lazily when exposed to only one SOA.

Electro-mechanical heat switch for cryogenic applications

DOEpatents

van den Berg, Marcel L.; Batteux, Jan D.; Labov, Simon E.

2003-01-01

A heat switch includes two symmetric jaws. Each jaw is comprised of a link connected at a translatable joint to a flexible arm. Each arm rotates about a fixed pivot, and has an articulated end including a thermal contact pad connected to a heat sink. The links are joined together at a translatable main joint. To close the heat switch, a closing solenoid is actuated and forces the main joint to an over-center position. This movement rotates the arms about their pivots, respectively, forces each of them into a stressed configuration, and forces the thermal contact pads towards each other and into compressive contact with a cold finger. The closing solenoid is then deactivated. The heat switch remains closed due to a restoring force generated by the stressed configuration of each arm, until actuation of an opening solenoid returns the main joint to its starting open-switch position.

Segway CMBalance Robot Soccer Player

DTIC Science & Technology

2004-05-01

Electrical pressure switch • (1) Onboard air compressor Figure .13 Pressure vs. Force Plot of a ¾ inch Bore Pneumatic Cylinder Two cylinders were used...mechanical pressure switch that opens at 150 psi. When the controller detects that the switch has closed, the compressor is turned off. As a

30 CFR 75.825 - Power centers.

Code of Federal Regulations, 2014 CFR

2014-07-01

....825 Power centers. (a) Main disconnecting switch. The power center supplying high voltage power to the continuous mining machine must be equipped with a main disconnecting switch that, when in the open position... the main disconnecting switch required in paragraph (a) of this section, the power center must be...

30 CFR 75.825 - Power centers.

Code of Federal Regulations, 2012 CFR

2012-07-01

....825 Power centers. (a) Main disconnecting switch. The power center supplying high voltage power to the continuous mining machine must be equipped with a main disconnecting switch that, when in the open position... the main disconnecting switch required in paragraph (a) of this section, the power center must be...

30 CFR 75.825 - Power centers.

Code of Federal Regulations, 2013 CFR

2013-07-01

....825 Power centers. (a) Main disconnecting switch. The power center supplying high voltage power to the continuous mining machine must be equipped with a main disconnecting switch that, when in the open position... the main disconnecting switch required in paragraph (a) of this section, the power center must be...

Open data for water-related operational services, the SWITCH-ON approach

NASA Astrophysics Data System (ADS)

Mazzoli, Paolo; Bagli, Stefano; Valerio, Luzzi; Broccoli, Davide; Piccinini, Francesca

2017-04-01

Recently, a collaborative project started called SWITCH-ON (EU FP7 project No 603587) coordinated by SMHI (http://water-switch-on.eu/) as part of the contemporary European movement imposed by the INSPIRE directive and the Open Data Strategy. Among It's R&D activities GECOsistema develops and expands inside SWITCH-ON a set of online services to tackle major water related issues, from reservoir and irrigation supply, to hydrological change adaptation and hydropower potential mapping. Here we present major releases of APRIL, HyCAW and High-resolution European HydroPower Atlas; all of which make intense use of open data. APRIL is a tool for seasonal run-off forecasts, that takes advantage of open datasets or low-cost data and performs forecasts through calibrated machine learning algorithms. HyCAW is a wizard that supports the assessment of adaptation options to cope with change in the temporal distribution of water availability as well as in the total water quantity. EU HPA provides all relevant information necessary to appraise the feasibility of a micro-hydropower plant at a specific site, taking into account hydrological as well as technical and economic factors. All the tools share a common vision of the project to address water concerns and currently untapped potential of open data for improved water management across the EU. Users are guided through a Web GIS interface, created using open source Web Mapping Applications, Open-Layers and Map Server, to explore available hydrological information in the area of interest, plot available data, perform analysis, and get reports and statistics.

Magnetic Force Switches for Magnetic Fluid Micromixing

NASA Astrophysics Data System (ADS)

Wei, Zung-Hang; Lee, Chiun-Peng; Lai, Mei-Feng

2010-01-01

A magnetic fluid micromixer with energy-saving magnetic force switches that can manipulate the magnetic fluid flow is proposed. The micromixer of high mixing efficiency uses single-domain micro magnets that have strong magnetic anisotropy to produce the magnetic force for the mixing. By altering the magnetization directions of the magnets that have different aspect ratios and coercivities, open and closed magnetic fluxes can be produced around each magnet cluster. For open magnetic flux, the mixing efficiency is numerically found to increase with the saturation magnetization of the magnets. On the contrary, the magnet clusters barely affects the mixing efficiency in the case of closed magnetic flux. Due to the different magnetic forces produced in open and closed magnetic fluxes, the magnetic fluid mixing can be switched on and off.

Open- and Closed-Skill Exercise Interventions Produce Different Neurocognitive Effects on Executive Functions in the Elderly: A 6-Month Randomized, Controlled Trial

PubMed Central

Tsai, Chia-Liang; Pan, Chien-Yu; Chen, Fu-Chen; Tseng, Yu-Ting

2017-01-01

This study aimed to explore the effects of open- and closed-skill exercise interventions on the neurocognitive performance of executive functions in the elderly. Sixty-four healthy elderly males were randomly assigned to either a closed-skill (bike riding or brisk walking/jogging, n = 22), open-skill (table tennis, n = 21), or control (n = 21) group. Various neuropsychological [e.g., accuracy rates (AR) and reaction time (RT)] and electrophysiological [e.g., event-related potential (ERP) P3 component] measures were assessed during a variant of the task-switching paradigm, as well as an N-back task at baseline and after either a 6-month exercise intervention or control period. The results showed that, when performing the task-switching paradigm, the two exercise groups relative to control group showed significantly faster RTs in the switch trials after the exercise intervention. However, the RT facilitation in the non-switch and switch trials post-exercise relative to pre-exercise only emerged in the open-skill group. In terms of the N-back task, the two exercise groups significantly increased ARs in the 1-back condition after the exercise intervention, and the beneficial AR effect on the 2-back condition only emerged in the closed-skill group. In addition, the two exercise groups exhibited significantly larger P3 amplitudes on the frontal-to-parietal cortex areas after the exercise intervention relative to the baseline when performing the two cognitive tasks. These neurocognitive results still remained unchanged even when the confounding factors (e.g., cardiorespiratory fitness, social participation, and BMI) were controlled for. The present study concluded that, although 6-month open- and closed-skill exercise interventions facilitate overall electrophysiological effects (i.e., increased ERP P3 amplitudes) on the frontal-to-parietal cortices in the elderly, the two exercise modes produced different levels of neuropsychologically beneficial effects on RTs of the task-switching paradigm (i.e., lessened RTs) and ARs of the N-back task (i.e., enhanced ARs). The distinctive neurocognitive changes induced by open- and closed-skill exercise have implications for task switching and working memory in elderly individuals, especially with such cognitive functioning impairments. PMID:28959200

Open LED Illuminator: A Simple and Inexpensive LED Illuminator for Fast Multicolor Particle Tracking in Neurons

PubMed Central

Bosse, Jens B.; Tanneti, Nikhila S.; Hogue, Ian B.; Enquist, Lynn W.

2015-01-01

Dual-color live cell fluorescence microscopy of fast intracellular trafficking processes, such as axonal transport, requires rapid switching of illumination channels. Typical broad-spectrum sources necessitate the use of mechanical filter switching, which introduces delays between acquisition of different fluorescence channels, impeding the interpretation and quantification of highly dynamic processes. Light Emitting Diodes (LEDs), however, allow modulation of excitation light in microseconds. Here we provide a step-by-step protocol to enable any scientist to build a research-grade LED illuminator for live cell microscopy, even without prior experience with electronics or optics. We quantify and compare components, discuss our design considerations, and demonstrate the performance of our LED illuminator by imaging axonal transport of herpes virus particles with high temporal resolution. PMID:26600461

Consequences of intravascular lymphatic valve properties: a study of contraction timing in a multi-lymphangion model

PubMed Central

Macaskill, Charlie; Davis, Michael J.; Moore, James E.

2016-01-01

The observed properties of valves in collecting lymphatic vessels include transmural pressure-dependent bias to the open state and hysteresis. The bias may reduce resistance to flow when the vessel is functioning as a conduit. However, lymphatic pumping implies a streamwise increase in mean pressure across each valve, suggesting that the bias is then potentially unhelpful. Lymph pumping by a model of several collecting lymphatic vessel segments (lymphangions) in series, which incorporated these properties, was investigated under conditions of adverse pressure difference while varying the refractory period between active muscular contractions and the inter-lymphangion contraction delay. It was found that many combinations of the timing parameters and the adverse pressure difference led to one or more intermediate valves remaining open instead of switching between open and closed states during repetitive contraction cycles. Cyclic valve switching was reliably indicated if the mean pressure in a lymphangion over a cycle was higher than that in the lymphangion upstream, but either lack of or very brief valve closure could cause mean pressure to be lower downstream. Widely separated combinations of refractory period and delay time were found to produce the greatest flow-rate for a given pressure difference. The efficiency of pumping was always maximized by a long refractory period and lymphangion contraction starting when the contraction of the lymphangion immediately upstream was peaking. By means of an ex vivo experiment, it was verified that intermediate valves in a chain of pumping lymphangions can remain open, while the lymphangions on either side of the open valve continue to execute contractions. PMID:26747501

Safety Analysis LOX-30 Liquid Oxygen Generator.

DTIC Science & Technology

1978-05-22

Valve. Protects the LOX—30 plant against over—pressurization. Valve opens at approximately 100 psig. (3) Oil Pressure Switch . Protects compressor...29 psig. d. Cryogenerator. •0 (1) 011 Pressure Switch . Prevents cryogenerator damage due to inadequate lubrication. The switch initiates system shut...when helium pressure is less than 200 psig, will result in compressor shut—down within ten seconds. (2) Differential Pressure Switch (2 each). These

46 CFR 160.115-7 - Design, construction, and performance of winches.

Code of Federal Regulations, 2014 CFR

2014-10-01

... materials. Provisions must also be made to prevent loosening or tightening resulting from differences of... opening of which disconnects all electrical potential to the winch, must be provided. This switch must be... either switch will disconnect all electrical potential of the circuit in which the switches are connected...

Scientific Notes (Problems of Cybernetics)

DTIC Science & Technology

1960-10-18

methodesworked out "by I, .P. P&vlov. ’ j ? The attainments cf neTirocyhernetI.es are opening new j [prospects for the in vest lotion ...created only for. a definite, state of the environment i. I and will expire If the environment changes, .Fiirtn-ars»©*’ i | its potentialities are no...orevious activities and to switch from one | i program of activity to another. I In this connection, the experiments conducted by thej famous Polish

Switching to sanitation: Understanding latrine adoption in a representative panel of rural Indian households.

PubMed

Coffey, Diane; Spears, Dean; Vyas, Sangita

2017-09-01

Open defecation, which is still practiced by about a billion people worldwide, is one of the most compelling examples of how place influences health in developing countries. Efforts by governments and development organizations to address the world's remaining open defecation would be greatly supported by a better understanding of why some people adopt latrines and others do not. We analyze the 2005 and 2012 rounds of the India Human Development Survey (IHDS), a nationally representative panel of households in India, the country which is home to 60% of the people worldwide who defecate in the open. Among rural households that defecated in the open in 2005, we investigate what baseline properties and what changes over time are associated with switching to latrine use between 2005 and 2012. We find that households that are richer or better educated, that have certain demographic properties, or that improved their homes over this period were more likely to switch to using a latrine or toilet. However, each of these effect sizes is small; overall switching to latrine use from open defecation is low; and no ready household-level mechanisms are available for sanitation programs to widely influence these factors. Our research adds to a growing consensus in the literature that the social context should not be overlooked when trying to understand and bring about change in sanitation behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ignition Characteristics at Low Ambient Pressures of a Full-Scale Injector Using H.T.P. and C-Fuel

DTIC Science & Technology

1951-06-01

to two effects: (i) The pressure switch was very sensitive and opened before the Miller recorder indicated a rise in pressure, (ii) The photocell used...cause an indeterminate in- crease in the measured ignition delay. In order to make the pressure switch less sensitive it was re-sot to open at about 55 lb

Should I Stay or Should I Switch? A Cost-Benefit Analysis of Voluntary Language Switching in Young and Aging Bilinguals

ERIC Educational Resources Information Center

Gollan, Tamar H.; Ferreira, Victor S.

2009-01-01

Bilinguals spontaneously switch languages in conversation even though laboratory studies reveal robust cued language switching costs. The authors investigated how voluntary-switching costs might differ when switches are voluntary. Younger (Experiments 1-2) and older (Experiment 3) Spanish-English bilinguals named pictures in 3 conditions: (a)…

Investigating a method for reducing residual switch costs in cued task switching.

PubMed

Schneider, Darryl W

2016-07-01

Residual switch costs in cued task switching are performance decrements that occur despite a long cue-target interval (CTI) to prepare for a task switch. Verbruggen, Liefooghe, Vandierendonck, and Demanet (Journal of Experimental Psychology: Learning, Memory, and Cognition, 33; 342-356, 2007) showed that briefly presenting the cue during the CTI and leaving it absent after target onset yielded smaller residual switch costs than those obtained when the cue was available for the full CTI and remained present after target onset. The potential effects of cue availability during the CTI (full or partial) and cue status after target onset (present or absent) on residual switch costs were investigated in the present study. In Experiments 1 and 2, cue status was manipulated while holding cue availability constant. In Experiments 3 and 4, cue status and cue availability were manipulated factorially. Residual switch costs were obtained, but they were not modulated consistently by cue status or cue availability across experiments. In Experiment 5, a direct replication of one of Verbruggen and colleagues' experiments yielded divergent results. Implications for understanding task switching are discussed.

The role of subjective frequency in language switching: An ERP investigation using masked priming

PubMed Central

Chauncey, Krysta; Grainger, Jonathan; Holcomb, Phillip J.

2012-01-01

Two experiments examined the nature of language-switching effects in a priming paradigm with event-related brain potential (ERP) recordings. primes and targets were always unrelated words but could be either from the same or different languages (Experiment 1) or from the same or a different frequency range (Experiment 2). Effects of switching language across prime and target differed as a function of the direction of the switch and prime duration in Experiment 1. Effects tended to be stronger with 100-ms prime durations than with 50-ms durations, and the expected pattern of greater negativity in the switch condition appeared earlier when primes were in L1 and targets in L2 than vice versa. Experiment 2 examined whether these language-switching effects could be due to differences in the subjective frequency of words in a bilingual’s two languages, by testing a frequency-switching manipulation within the L1. Effects of frequency switching were evident in the ERP waveforms, but the pattern did not resemble the language-switching effects, therefore suggesting that different mechanisms are at play. PMID:21264577

Dissociating Stimulus-Set and Response-Set in the Context of Task-Set Switching

PubMed Central

Kieffaber, Paul D.; Kruschke, John K.; Cho, Raymond Y.; Walker, Philip M.; Hetrick, William P.

2014-01-01

The primary aim of the present research was to determine how stimulus-set and response-set components of task-set contribute to switch costs and conflict processing. Three experiments are described wherein participants completed an explicitly cued task-switching procedure. Experiment 1 established that task switches requiring a reconfiguration of both stimulus- and response-set incurred larger residual switch costs than task switches requiring the reconfiguration of stimulus-set alone. Between-task interference was also drastically reduced for response-set conflict compared with stimulus-set conflict. A second experiment replicated these findings and demonstrated that stimulus- and response-conflict have dissociable effects on the “decision time” and “motor time” components of total response time. Finally, a third experiment replicated Experiment 2 and demonstrated that the stimulus- and response- components of task switching and conflict processing elicit dissociable neural activity as evidence by event-related brain potentials. PMID:22984990

Ames Lab 101: Ultrafast Magnetic Switching

ScienceCinema

Wang; Jigang

2018-01-01

Ames Laboratory physicists have found a new way to switch magnetism that is at least 1000 times faster than currently used in magnetic memory technologies. Magnetic switching is used to encode information in hard drives, magnetic random access memory and other computing devices. The discovery potentially opens the door to terahertz and faster memory speeds.

PWM-switching pattern-based diagnosis scheme for single and multiple open-switch damages in VSI-fed induction motor drives.

PubMed

Trabelsi, Mohamed; Boussak, Mohamed; Gossa, Moncef

2012-03-01

This paper deals with a fault detection technique for insulated-gate bipolar transistors (IGBTs) open-circuit faults in voltage source inverter (VSI)-fed induction motor drives. The novelty of this idea consists in analyzing the pulse-width modulation (PWM) switching signals and the line-to-line voltage levels during the switching times, under both healthy and faulty operating conditions. The proposed method requires line-to-line voltage measurement, which provides information about switching states and is not affected by the load. The fault diagnosis scheme is achieved using simple hardware and can be included in the existing inverter system without any difficulty. In addition, it allows not only accurate single and multiple faults diagnosis but also minimization of the fault detection time to a maximum of one switching period (T(c)). Simulated and experimental results on a 3-kW squirrel-cage induction motor drive are displayed to validate the feasibility and the effectiveness of the proposed strategy. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

High peak and high average radiofrequency power transmit/receive switch for thermal magnetic resonance.

PubMed

Ji, Yiyi; Hoffmann, Werner; Pham, Michal; Dunn, Alexander E; Han, Haopeng; Özerdem, Celal; Waiczies, Helmar; Rohloff, Michael; Endemann, Beate; Boyer, Cyrille; Lim, May; Niendorf, Thoralf; Winter, Lukas

2018-04-01

To study the role of temperature in biological systems, diagnostic contrasts and thermal therapies, RF pulses for MR spin excitation can be deliberately used to apply a thermal stimulus. This application requires dedicated transmit/receive (Tx/Rx) switches that support high peak powers for MRI and high average powers for RF heating. To meet this goal, we propose a high-performance Tx/Rx switch based on positive-intrinsic-negative diodes and quarter-wavelength (λ/4) stubs. The λ/4 stubs in the proposed Tx/Rx switch design route the transmitted RF signal directly to the RF coil/antenna without passing through any electronic components (e.g., positive-intrinsic-negative diodes). Bench measurements, MRI, MR thermometry, and RF heating experiments were performed at f = 297 MHz (B 0  = 7 T) to examine the characteristics and applicability of the switch. The proposed design provided an isolation of -35.7dB/-41.5dB during transmission/reception. The insertion loss was -0.41dB/-0.27dB during transmission/reception. The switch supports high peak (3.9 kW) and high average (120 W) RF powers for MRI and RF heating at f = 297 MHz. High-resolution MRI of the wrist yielded image quality competitive with that obtained with a conventional Tx/Rx switch. Radiofrequency heating in phantom monitored by MR thermometry demonstrated the switch applicability for thermal modulation. Upon these findings, thermally activated release of a model drug attached to thermoresponsive polymers was demonstrated. The high-power Tx/Rx switch enables thermal MR applications at 7 T, contributing to the study of the role of temperature in biological systems and diseases. All design files of the switch will be made available open source at www.opensourceimaging.org. © 2018 International Society for Magnetic Resonance in Medicine.

--No Title--

Science.gov Websites

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Research and Development of Silicon Carbide (SiC) Junction Recovery Diodes for Picosecond Range, High Power Opening Switches

NASA Astrophysics Data System (ADS)

Grekhov, Igor V.

2002-07-01

This report results from a contract tasking Ioffe Institute as follows: The purpose of the proposed project is to develop, fabricate, test, and characterize silicon carbide power semiconductor opening switches operating in the picosecond range of switch time. Special SiC diode structures will be fabricated and investigated, including Junction Recovery Diodes (JRD). The operation of such diodes is founded on the superfast recovery of the junction's blocking ability after switching the device from forward to reverse bias conditions. Our estimations show that the parameters of JRD devices can be substantially improved in case of SiC devices, compared to both Si and GaAs capabilities. We expect i) to increase the speed of switch operation, the specific commutated power, and the operation frequency repetition; ii) to reduce the weight and size of pulse devices; and iii) to achieve better reliability of the devices due to the unique thermal conductivity and radiation hardness of SiC.

Repetitive switching for an electromagnetic rail gun

NASA Astrophysics Data System (ADS)

Gruden, J. M.

1983-12-01

Previous testing on a repetitive opening switch for inductive energy storage has proved the feasibility of the rotary switch concept. The concept consists of a rotating copper disk (rotor) with a pie-shaped insulator section and brushes which slide along each of the rotor surfaces. While on top of the copper surface, the brushes and rotor conduct current allowing the energy storage inductor to charge. When the brushes slide onto the insulator section, the current cannot pass through the rotor and is diverted into the load. This study investigates two new brush designs and a rotor modification designed to improve the current commutating capabilities of the switch. One brush design (fringe fiber) employs carbon fibers on the leading and trailing edge of the brush to increase the resistive commutating action as the switch opens and closes. The other brush design uses fingers to conduct current to the rotor surface, effectively increasing the number of brush contact points. The rotor modification was the placement of tungsten inserts at the copper-insulator interfaces.

Switched Broadband Services For The Home

NASA Astrophysics Data System (ADS)

Sawyer, Don M.

1990-01-01

In considering the deployment of fiber optics to the residence, two critical questions arise: what are the leading services that could be offered to justify the required investment; and what is the nature of the business that would offer these services to the consumer ? This talk will address these two questions together with the related issue of how the "financial engine" of today's television distribution infrastructure - TV advertising - would be affected by an open access system based on fiber optics coupled with broadband switching. On the business side, the talk concludes that the potential for open ended capacity expansion, fair competition between service providers, and new interactive services inherent in an open access, switched broadband system are the critical items in differentiating it from existing video and TV distribution systems. On the question of broadband services, the talk will highlight several new opportunities together with some findings from recent market research conducted by BNR. The talk will show that there are variations on existing services plus many new services that could be offered and which have real consumer appeal. The postulated open access system discussed here is visualized as having ultimately 1,000 to 2,000 video channels available to the consumer. Although this may appear to hopelessly fragment the TV audience and destroy the current TV advertising infrastructure, the technology of open access, switched broadband will present many new advertising techniques, which have the potential to be far more effective than those available today. Some of these techniques will be described in this talk.

Plasma opening switch

DOEpatents

Savage, Mark E.; Mendel, Jr., Clifford W.

2001-01-01

A command triggered plasma opening switch assembly using an amplification stage. The assembly surrounds a coaxial transmission line and has a main plasma opening switch (POS) close to the load and a trigger POS upstream from the main POS. The trigger POS establishes two different current pathways through the assembly depended on whether it has received a trigger current pulse. The initial pathway has both POS's with plasma between their anodes and cathodes to form a short across the transmission line and isolating the load. The final current pathway is formed when the trigger POS receives a trigger current pulse which energizes its fast coil to push the conductive plasma out from between its anode and cathode, allowing the main transmission line current to pass to the fast coil of the main POS, thus pushing its plasma out the way so as to establish a direct current pathway to the load.

Phenotypic states become increasingly sensitive to perturbations near a bifurcation in a synthetic gene network.

PubMed

Axelrod, Kevin; Sanchez, Alvaro; Gore, Jeff

2015-08-24

Microorganisms often exhibit a history-dependent phenotypic response after exposure to a stimulus which can be imperative for proper function. However, cells frequently experience unexpected environmental perturbations that might induce phenotypic switching. How cells maintain phenotypic states in the face of environmental fluctuations remains an open question. Here, we use environmental perturbations to characterize the resilience of phenotypic states in a synthetic gene network near a critical transition. We find that far from the critical transition an environmental perturbation may induce little to no phenotypic switching, whereas close to the critical transition the same perturbation can cause many cells to switch phenotypic states. This loss of resilience was observed for perturbations that interact directly with the gene circuit as well as for a variety of generic perturbations-such as salt, ethanol, or temperature shocks-that alter the state of the cell more broadly. We obtain qualitatively similar findings in natural gene circuits, such as the yeast GAL network. Our findings illustrate how phenotypic memory can become destabilized by environmental variability near a critical transition.

Supplementary insurance as a switching cost for basic health insurance: Empirical results from the Netherlands.

PubMed

Willemse-Duijmelinck, Daniëlle M I D; van de Ven, Wynand P M M; Mosca, Ilaria

2017-10-01

Nearly everyone with a supplementary insurance (SI) in the Netherlands takes out the voluntary SI and the mandatory basic insurance (BI) from the same health insurer. Previous studies show that many high-risks perceive SI as a switching cost for BI. Because consumers' current insurer provides them with a guaranteed renewability, SI is a switching cost if insurers apply selective underwriting to new applicants. Several changes in the Dutch health insurance market increased insurers' incentives to counteract adverse selection for SI. Tools to do so are not only selective underwriting, but also risk rating and product differentiation. If all insurers use the latter tools without selective underwriting, SI is not a switching cost for BI. We investigated to what extent insurers used these tools in the periods 2006-2009 and 2014-2015. Only a few insurers applied selective underwriting: in 2015, 86% of insurers used open enrolment for all their SI products, and the other 14% did use open enrolment for their most common SI products. As measured by our indicators, the proportion of insurers applying risk rating or product differentiation did not increase in the periods considered. Due to the fear of reputation loss insurers may have used 'less visible' tools to counteract adverse selection that are indirect forms of risk rating and product differentiation and do not result in switching costs. So, although many high-risks perceive SI as a switching cost, most insurers apply open enrolment for SI. By providing information to high-risks about their switching opportunities, the government could increase consumer choice and thereby insurers' incentives to invest in high-quality care for high-risks. Copyright © 2017 Elsevier B.V. All rights reserved.

52. View from ground level showing lower radar scanner switch ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

52. View from ground level showing lower radar scanner switch with open port door in radar scanner building 105 showing emanating waveguides from lower switch in vertical run; photograph also shows catwalk to upper scanner switch in upper left side of photograph and structural supports. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

54. View from ground level in building no. 105 showing ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

54. View from ground level in building no. 105 showing lower radar scanner switch at open port door. Note incoming waveguide and control switch at lower left of photograph and note several waveguides leaving top of scanner switch around the circumference of switch. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

Electronic logic for enhanced switch reliability

DOEpatents

Cooper, J.A.

1984-01-20

A logic circuit is used to enhance redundant switch reliability. Two or more switches are monitored for logical high or low output. The output for the logic circuit produces a redundant and fail-safe representation of the switch outputs. When both switch outputs are high, the output is high. Similarly, when both switch outputs are low, the logic circuit's output is low. When the output states of the two switches do not agree, the circuit resolves the conflict by memorizing the last output state which both switches were simultaneously in and produces the logical complement of this output state. Thus, the logic circuit of the present invention allows the redundant switches to be treated as if they were in parallel when the switches are open and as if they were in series when the switches are closed. A failsafe system having maximum reliability is thereby produced.

Using a small hybrid pulse power transformer unit as component of a high-current opening switch for a railgun

NASA Astrophysics Data System (ADS)

Leung, E. M. W.; Bailey, R. E.; Michels, P. H.

1989-03-01

The hybrid pulse power transformer (HPPT) is a unique concept utilizing the ultrafast superconducting-to-normal transition process of a superconductor. When used in the form of a hybrid transformer current-zero switch (HTCS), this creates an approach in which the large, high-power, high-current opening switch in a conventional railgun system can be eliminated. This represents an innovative application of superconductivity to pulsed power conditioning required for the Strategic Defense Initiative (SDI). The authors explain the working principles of a 100-KJ unit capable of switching up to 500 kA at a frequency of 0.5 Hz and with a system efficiency of greater than 90 percent. Circuit analysis using a computer code called SPICE PLUS was used to verify the HTCS concept. This concept can be scaled up to applications in the several mega-ampere levels.

Bilingual Voicing: A Study of Code-Switching in the Reported Speech of Finnish Immigrants in Estonia

ERIC Educational Resources Information Center

Frick, Maria; Riionheimo, Helka

2013-01-01

Through a conversation analytic investigation of Finnish-Estonian bilingual (direct) reported speech (i.e., voicing) by Finns who live in Estonia, this study shows how code-switching is used as a double contextualization device. The code-switched voicings are shaped by the on-going interactional situation, serving its needs by opening up a context…

76 FR 19795 - Exelon Generation Company, LLC; Oyster Creek Nuclear Generating Station; Exemption

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-08

... Recirculation and close V-11- Motor Generator 63 and V-11-41. (MG) Set Room Elev. 23'-6''. Manually open V- 12... ``Alternate'' and operate Control Switch on Diesel Panel to start diesel). Manually re-close 6 MCC 1B32 Feeder... transfer Switches (3 total) to ``Alternate'' and operate Control Switch on Diesel Panel to start diesel...

Mega-Amp Opening Switch with Nested Electrodes/Pulsed Generator of Ion and Ion Cluster Beams.

DTIC Science & Technology

1985-07-01

i.e., noncollisiona].) resistivity which controls the "~switch opening" function (specifically, the rate of disintergration of the PF pinch where...unaffected the pinch field Be and then disassemble in a light (D) component and other heavy components. Production and propagation of-neutrals (from...emission, production and - evaporation would imply a distorsion of the pinholeimage-because of B -which is not p.-.. observed (our pinhole resolution is 150

Mindset switching increases the use of 'want-based' over 'should-based' behaviors

PubMed Central

Zhang, Nan-Nan; Xu, Dai-Xuan

2018-01-01

This study examines the consequences of mindset switching on behavioral choices in want/should conflicts. Building on the insights of the ego depletion literature, we propose that mindset switching depletes individuals’ self-control resources and therefore prompts the choice of want behavior, which provides immediate pleasure, over should behavior, which provides long-term utility. Four laboratory experiments with university students that stimulated individuals to switch mindsets were conducted to test our hypotheses. Experiment 1 demonstrated that switching between individualist and collectivist mindsets increased the subjects’ tendency to prefer popular magazines over scientific journals. Experiment 2 replicated the results by testing the relationship between an abstract/concrete mindset-switching task and want/should online behavioral choices. The mediating effect of ego depletion was also supported. Experiment 3 retested the main effect of language-switching on reading choices, and the mediating effect of ego-depletion. Experiment 3 also tested the moderating effect of the Need for Cognition, and eliminated the alternative explanation of cognitive fatigue. In Experiment 4, actual food choices were used as the direct measure of want/should behaviors to test the robustness of our findings. The results consistently supported our hypotheses that mindset switching has significant effects on behavioral choices in terms of overindulgence, such as increasing want behavior and thus foregoing should behavior. PMID:29709003

Understanding nucleotide-regulated FtsZ filament dynamics and the monomer assembly switch with large-scale atomistic simulations.

PubMed

Ramírez-Aportela, Erney; López-Blanco, José Ramón; Andreu, José Manuel; Chacón, Pablo

2014-11-04

Bacterial cytoskeletal protein FtsZ assembles in a head-to-tail manner, forming dynamic filaments that are essential for cell division. Here, we study their dynamics using unbiased atomistic molecular simulations from representative filament crystal structures. In agreement with experimental data, we find different filament curvatures that are supported by a nucleotide-regulated hinge motion between consecutive FtsZ monomers. Whereas GTP-FtsZ filaments bend and twist in a preferred orientation, thereby burying the nucleotide, the differently curved GDP-FtsZ filaments exhibit a heterogeneous distribution of open and closed interfaces between monomers. We identify a coordinated Mg(2+) ion as the key structural element in closing the nucleotide site and stabilizing GTP filaments, whereas the loss of the contacts with loop T7 from the next monomer in GDP filaments leads to open interfaces that are more prone to depolymerization. We monitored the FtsZ monomer assembly switch, which involves opening/closing of the cleft between the C-terminal domain and the H7 helix, and observed the relaxation of isolated and filament minus-end monomers into the closed-cleft inactive conformation. This result validates the proposed switch between the low-affinity monomeric closed-cleft conformation and the active open-cleft FtsZ conformation within filaments. Finally, we observed how the antibiotic PC190723 suppresses the disassembly switch and allosterically induces closure of the intermonomer interfaces, thus stabilizing the filament. Our studies provide detailed structural and dynamic insights into modulation of both the intrinsic curvature of the FtsZ filaments and the molecular switch coupled to the high-affinity end-wise association of FtsZ monomers.

Mixed Monolayers of Spiropyrans Maximize Tunneling Conductance Switching by Photoisomerization at the Molecule–Electrode Interface in EGaIn Junctions

PubMed Central

2016-01-01

This paper describes the photoinduced switching of conductance in tunneling junctions comprising self-assembled monolayers of a spiropyran moiety using eutectic Ga–In top contacts. Despite separation of the spiropyran unit from the electrode by a long alkyl ester chain, we observe an increase in the current density J of a factor of 35 at 1 V when the closed form is irradiated with UV light to induce the ring-opening reaction, one of the highest switching ratios reported for junctions incorporating self-assembled monolayers. The magnitude of switching of hexanethiol mixed monolayers was higher than that of pure spiropyran monolayers. The first switching event recovers 100% of the initial value of J and in the mixed-monolayers subsequent dampening is not the result of degradation of the monolayer. The observation of increased conductivity is supported by zero-bias DFT calculations showing a change in the localization of the density of states near the Fermi level as well as by simulated transmission spectra revealing positive resonances that broaden and shift toward the Fermi level in the open form. PMID:27602432

Mega-Amp Opening Switch with Nested Electrodes/Pulsed Generator of Ion and Ion Cluster Beams

DTIC Science & Technology

1987-07-30

The use of a plasma focus as a mega-amp opening switch has been demonstrated by two modes of operation: (a) Single shot mode; (b) Repetitive Mode...energy level and under the same voltage and filling-pressure conditions but without field distortion elements. Misfirings of the plasma focus machine...are also virtually eliminated by using FDE at the coaxial electrode breech. The tests (based on about 10000 shots and five plasma focus machines

Dissociating Stimulus-Set and Response-Set in the Context of Task-Set Switching

ERIC Educational Resources Information Center

Kieffaber, Paul D.; Kruschke, John K.; Cho, Raymond Y.; Walker, Philip M.; Hetrick, William P.

2013-01-01

The primary aim of the present research was to determine how "stimulus-set" and "response-set" components of task-set contribute to switch costs and conflict processing. Three experiments are described wherein participants completed an explicitly cued task-switching procedure. Experiment 1 established that task switches requiring a reconfiguration…

On the role of verbalization during task set selection: switching or serial order control?

PubMed

Bryck, Richard L; Mayr, Ulrich

2005-06-01

Recent task-switching work in which paper-and-pencil administered single-task lists were compared with task-alternation lists has demonstrated large increases in task-switch costs with concurrent articulatory suppression (AS), implicating a crucial role for verbalization during switching (Baddeley, Chincotta, & Adlam, 2001; Emerson & Miyake, 2003). Experiment 1 replicated this result, using computerized assessment, albeit with much smaller effect sizes than in the original reports. In Experiment 2, AS interference was reduced when a sequential cue (spatial location) that indicated the current position in the sequence of task alternations was given. Finally, in Experiment 3, switch trials and no-switch trials were compared within a block of alternating runs of two tasks. Again, AS interference was obtained mainly when the endogenous sequencing demand was high, and it was comparable for no-switch and switch trials. These results suggest that verbalization may be critical for endogenous maintenance and updating of a sequential plan, rather than exclusively for the actual switching process.

17. DETAIL OF CONTROL PANEL FOR FILTER #9: CONTROL SWITCHES ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

17. DETAIL OF CONTROL PANEL FOR FILTER #9: CONTROL SWITCHES CONTROL BY PERCENTAGE OF VALVE OPENINGS INFLUENT, EFFLUENT, DRAINAGE, BACKWASH AND SURFACE WASH. - F. E. Weymouth Filtration Plant, 700 North Moreno Avenue, La Verne, Los Angeles County, CA

Fast-responding short circuit protection system with self-reset for use in circuit supplied by DC power

NASA Technical Reports Server (NTRS)

Burns, Bradley M. (Inventor); Blalock, Norman N. (Inventor)

2011-01-01

A short circuit protection system includes an inductor, a switch, a voltage sensing circuit, and a controller. The switch and inductor are electrically coupled to be in series with one another. A voltage sensing circuit is coupled across the switch and the inductor. A controller, coupled to the voltage sensing circuit and the switch, opens the switch when a voltage at the output terminal of the inductor transitions from above a threshold voltage to below the threshold voltage. The controller closes the switch when the voltage at the output terminal of the inductor transitions from below the threshold voltage to above the threshold voltage.

Sequential magnetic switching in Fe/MgO(001) superlattices

NASA Astrophysics Data System (ADS)

Magnus, F.; Warnatz, T.; Palsson, G. K.; Devishvili, A.; Ukleev, V.; Palisaitis, J.; Persson, P. O. Å.; Hjörvarsson, B.

2018-05-01

Polarized neutron reflectometry is used to determine the sequence of magnetic switching in interlayer exchange coupled Fe/MgO(001) superlattices in an applied magnetic field. For 19.6 Å thick MgO layers we obtain a 90∘ periodic magnetic alignment between adjacent Fe layers at remanence. In an increasing applied field the top layer switches first followed by its second-nearest neighbor. For 16.4 Å MgO layers, a 180∘ periodic alignment is obtained at remanence and with increasing applied field the layer switching starts from the two outermost layers and proceeds inwards. This sequential tuneable switching opens up the possibility of designing three-dimensional magnetic structures with a predefined discrete switching sequence.

Task switching and response correspondence in the psychological refractory period paradigm

NASA Technical Reports Server (NTRS)

Lien, Mei-Ching; Schweickert, Richard; Proctor, Robert W.

2003-01-01

Three experiments examined the effects of task switching and response correspondence in a psychological refractory period paradigm. A letter task (vowel-consonant) and a digit task (odd-even) were combined to form 4 possible dual-task pairs in each trial: letter-letter, letter-digit, digit-digit, and digit-letter. Foreknowledge of task transition (repeat or switch) and task identity (letter or digit) was varied across experiments: no foreknowledge in Experiment 1, partial foreknowledge (task transition only) in Experiment 2, and full foreknowledge in Experiment 3. For all experiments, the switch cost for Task 2 was additive with stimulus onset asynchrony, and the response-correspondence effect for Task 2 was numerically smaller in the switch condition than in the repeat condition. These outcomes suggest that reconfiguration for Task 2 takes place after the central processing of Task 1 and that the crosstalk correspondence effect is due to response activation by way of stimulus-response associations.

Defense switched network technology and experiments program

NASA Astrophysics Data System (ADS)

Weinstein, C. J.

1983-09-01

This report documents work performed during FY 1983 on the DCA-sponsored Defense Switched Network Technology and Experiments Program. The areas of work reported are: (1) development of routing algorithms for application in the Defense Switched Network (DSN); (2) instrumentation and integration of the Experimental Integrated Switched Network (EISN) test facility; (3) development and test of data communication techniques using DoD-standard data protocols in an integrated voice/data network; and (4) EISN system coordination and experiment planning.

Novel control system of the high-voltage IGBT-switch

NASA Astrophysics Data System (ADS)

Ponomarev, A. V.; Mamontov, Y. I.; Gusev, A. I.; Pedos, M. S.

2017-05-01

HV solid-state switch control circuit was developed and tested. The switch was made with series connection IGBT-transistors. The distinctive feature of the circuit is an ability to fine-tune the switching time of every transistor. Simultaneous switching provides balancing of the dynamic voltage at all switch elements. A separate control board switches on and off every transistor. On and off signals from the main conductor are sent to the board by current pulses of different polarity. A positive pulse provides the transistor switch-on, while a negative pulse provides their switch-off. The time interval between pulses defines the time when the switch is turned on. The minimum time when the switch is turned on equals to a few microseconds, while the maximum time is not limited. This paper shows the test results of 4 kV switch prototype. The switch was used to produce rectangular pulses of a microsecond range under resistive load. The possibility to generate the damped harmonic oscillations was also tested. On the basis of this approach, positive testing results open up a possibility to design switches under an operating voltage of tens kilovolts.

Multi-Domain SDN Survivability for Agricultural Wireless Sensor Networks.

PubMed

Huang, Tao; Yan, Siyu; Yang, Fan; Liu, Jiang

2016-11-06

Wireless sensor networks (WSNs) have been widely applied in agriculture field; meanwhile, the advent of multi-domain software-defined networks (SDNs) have improved the wireless resource utilization rate and strengthened network management. In recent times, multi-domain SDNs have been applied to agricultural sensor networks, namely multi-domain software-defined wireless sensor networks (SDWSNs). However, when the SDNs controlling agriculture networks suddenly become unavailable, whether intra-domain or inter-domain, sensor network communication is abnormal because of the loss of control. Moreover, there are controller and switch info-updating problems even if the controller becomes available again. To resolve these problems, this paper proposes a new approach based on an Open vSwitch extension for multi-domain SDWSNs, which can enhance agriculture network survivability and stability. We achieved this by designing a connection-state mechanism, a communication mechanism on both L2 and L3, and an info-updating mechanism based on Open vSwitch. The experimental results show that, whether it is agricultural inter-domain or intra-domain during the controller failure period, the sensor switches can enter failure recovery mode as soon as possible so that the sensor network keeps a stable throughput, a short failure recovery time below 300 ms, and low packet loss. Further, the domain can smoothly control the domain network again once the controller becomes available. This approach based on an Open vSwitch extension can enhance the survivability and stability of multi-domain SDWSNs in precision agriculture.

Multi-Domain SDN Survivability for Agricultural Wireless Sensor Networks

PubMed Central

Huang, Tao; Yan, Siyu; Yang, Fan; Liu, Jiang

2016-01-01

Wireless sensor networks (WSNs) have been widely applied in agriculture field; meanwhile, the advent of multi-domain software-defined networks (SDNs) have improved the wireless resource utilization rate and strengthened network management. In recent times, multi-domain SDNs have been applied to agricultural sensor networks, namely multi-domain software-defined wireless sensor networks (SDWSNs). However, when the SDNs controlling agriculture networks suddenly become unavailable, whether intra-domain or inter-domain, sensor network communication is abnormal because of the loss of control. Moreover, there are controller and switch info-updating problems even if the controller becomes available again. To resolve these problems, this paper proposes a new approach based on an Open vSwitch extension for multi-domain SDWSNs, which can enhance agriculture network survivability and stability. We achieved this by designing a connection-state mechanism, a communication mechanism on both L2 and L3, and an info-updating mechanism based on Open vSwitch. The experimental results show that, whether it is agricultural inter-domain or intra-domain during the controller failure period, the sensor switches can enter failure recovery mode as soon as possible so that the sensor network keeps a stable throughput, a short failure recovery time below 300 ms, and low packet loss. Further, the domain can smoothly control the domain network again once the controller becomes available. This approach based on an Open vSwitch extension can enhance the survivability and stability of multi-domain SDWSNs in precision agriculture. PMID:27827971

Socioeconomic Impact Assessment: Communications Industry. Phase III. Technology Forecast.

DTIC Science & Technology

1979-02-02

8217. Some add-on devices , such as automatic answering systems, have already penetrated the home market substantially. In the future, however, ( major changes ...equipment. This class includes garage door openers, wireless micro- phones , cordless telephones, and radio and TV receivers. These -( devices can...ACUMENICS 1-9 1.2.2 Switching Devices The first automatic switching devices which began to replace operator-switched telephone traffic in the early

Assumption or Fact? Line-to-Neutral Voltage Expression in an Unbalanced 3-Phase Circuit during Inverter Switching

ERIC Educational Resources Information Center

Masrur, M. A.

2009-01-01

This paper discusses the situation in a 3-phase motor or any other 3-phase system operating under unbalanced operating conditions caused by an open fault in an inverter switch. A dc voltage source is assumed as the input to the inverter, and under faulty conditions of the inverter switch, the actual voltage applied between the line to neutral…

Space-charge-mediated anomalous ferroelectric switching in P(VDF-TrEE) polymer films.

PubMed

Hu, Weijin; Wang, Zhihong; Du, Yuanmin; Zhang, Xi-Xiang; Wu, Tom

2014-11-12

We report on the switching dynamics of P(VDF-TrEE) copolymer devices and the realization of additional substable ferroelectric states via modulation of the coupling between polarizations and space charges. The space-charge-limited current is revealed to be the dominant leakage mechanism in such organic ferroelectric devices, and electrostatic interactions due to space charges lead to the emergence of anomalous ferroelectric loops. The reliable control of ferroelectric switching in P(VDF-TrEE) copolymers opens doors toward engineering advanced organic memories with tailored switching characteristics.

Note: Switching crosstalk on and off in Kelvin probe force microscopy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Polak, Leo, E-mail: l.polak@vu.nl; Wijngaarden, Rinke J.; Man, Sven de

2014-04-15

In Kelvin Probe Force Microscopy (KPFM) electronic crosstalk can occur between the excitation signal and probe deflection signal. Here, we demonstrate how a small modification to our commercial instrument enables us to literally switch the crosstalk on and off. We study in detail the effect of crosstalk on open-loop KPFM and compare with closed-loop KPFM. We measure the pure crosstalk signal and verify that we can correct for it in the data-processing required for open-loop KPFM. We also demonstrate that open-loop KPFM results are independent of the frequency and amplitude of the excitation signal, provided that the influence of crosstalkmore » has been eliminated.« less

FAST OPENING SWITCH

DOEpatents

Bender, M.; Bennett, F.K.; Kuckes, A.F.

1963-09-17

A fast-acting electric switch is described for rapidly opening a circuit carrying large amounts of electrical power. A thin, conducting foil bridges a gap in this circuit and means are provided for producing a magnetic field and eddy currents in the foil, whereby the foil is rapidly broken to open the circuit across the gap. Advantageously the foil has a hole forming two narrow portions in the foil and the means producing the magnetic field and eddy currents comprises an annular coil having its annulus coaxial with the hole in the foil and turns adjacent the narrow portions of the foil. An electrical current flows through the coil to produce the magnetic field and eddy currents in the foil. (AEC)

Open-systems Architecture of a Standardized Command Interface Chip-set for Switching and Control of a Spacecraft Power Bus

NASA Technical Reports Server (NTRS)

Ruiz, B. Ian; Burke, Gary R.; Lung, Gerald; Whitaker, William D.; Nowicki, Robert M.

2004-01-01

This viewgraph presentation reviews the architecture of the The CIA-AlA chip-set is a set of mixed-signal ASICs that provide a flexible high level interface between the spacecraft's command and data handling (C&DH) electronics and lower level functions in other spacecraft subsystems. Due to the open-systems architecture of the chip-set including an embedded micro-controller a variety of applications are possible. The chip-set was developed for the missions to the outer planets. The chips were developed to provide a single solution for both the switching and regulation of a spacecraft power bus. The Open-Systems Architecture allows for other powerful applications.

Selective attention to perceptual dimensions and switching between dimensions.

PubMed

Meiran, Nachshon; Dimov, Eduard; Ganel, Tzvi

2013-02-01

In the present experiments, the question being addressed was whether switching attention between perceptual dimensions and selective attention to dimensions are processes that compete over a common resource? Attention to perceptual dimensions is usually studied by requiring participants to ignore a never-relevant dimension. Selection failure (Garner's Interference, GI) is indicated by poorer performance in the filtering condition (when this dimension varies) as compared with baseline (when it is fixed). Switching between perceptual dimensions is usually studied with the task switching paradigm. In the present experiments, attention switching was manipulated by using single-task blocks and blocks in which participants switched between tasks or dimensions in reaction to task cues, and attention to dimensions was assessed by including a third, never-relevant dimension that was either fixed or varied randomly. In Experiments 1 (long cue-target interval, CTI) and 2 (short CTI), the tasks involved shape and color and the never-relevant dimension (texture) was chosen to be separable from them. In Experiments 3 (long CTI) and 4 (short CTI), the tasks involved shape and brightness and the never-relevant dimension, saturation, was chosen to be separable from shape and integral with brightness. Task switching did not generate GI but a short CTI did. Thus, switching and filtering generally do not compete over central limited resources unless under tight time pressure. Experiment 3 shows GI in the brightness task but not in the shape task, suggesting that participants switched their attention between brightness and shape when they switched tasks. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Task switching in a hierarchical task structure: evidence for the fragility of the task repetition benefit.

PubMed

Lien, Mei-Ching; Ruthruff, Eric

2004-05-01

This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms. In Experiments 2-5, adjacent task elements were grouped temporally and/or spatially (forming an ensemble) to create a hierarchical task organization. Results indicate that the effect of switching at the ensemble level dominated the effect of switching at the element level. Experiments 6 and 7, using an ensemble of 3 task elements, revealed that the element-level switch cost was virtually absent between ensembles but was large within an ensemble. The authors conclude that the element-level task repetition benefit is fragile and can be eliminated in a hierarchical task organization.

Task switching in a hierarchical task structure: evidence for the fragility of the task repetition benefit

NASA Technical Reports Server (NTRS)

Lien, Mei-Ching; Ruthruff, Eric

2004-01-01

This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms. In Experiments 2-5, adjacent task elements were grouped temporally and/or spatially (forming an ensemble) to create a hierarchical task organization. Results indicate that the effect of switching at the ensemble level dominated the effect of switching at the element level. Experiments 6 and 7, using an ensemble of 3 task elements, revealed that the element-level switch cost was virtually absent between ensembles but was large within an ensemble. The authors conclude that the element-level task repetition benefit is fragile and can be eliminated in a hierarchical task organization.

Real time pressure signal system for a rotary engine

NASA Technical Reports Server (NTRS)

Rice, W. J. (Inventor)

1984-01-01

A real-time IMEP signal which is a composite of those produced in any one chamber of a three-lobed rotary engine is developed by processing the signals of four transducers positioned in a Wankel engine housing such that the rotor overlaps two of the transducers for a brief period during each cycle. During the overlap period of any two transducers, their output is compared and sampled for 10 microseconds per 0.18 degree of rotation by a sampling switch and capacitive circuit. When the switch is closed, the instantaneous difference between the value of the transducer signals is provided while with the switch open the average difference is produced. This combined signal, along with the original signal of the second transducer, is fed through a multiplexer to a pressure output terminal. Timing circuits, controlled by a crank angle encoder on the engine, determine which compared transducer signals are applied to the output terminal and when, as well as the open and closed periods of the switches.

Nudging Leads Consumers In Colorado To Shop But Not Switch ACA Marketplace Plans.

PubMed

Marzilli Ericson, Keith M; Kingsdale, Jon; Layton, Tim; Sacarny, Adam

2017-02-01

The Affordable Care Act (ACA) dramatically expanded the use of regulated marketplaces in health insurance, but consumers often fail to shop for plans during open enrollment periods. Typically these consumers are automatically reenrolled in their old plans, which potentially exposes them to unexpected increases in their insurance premiums and cost sharing. We conducted a randomized intervention to encourage enrollees in an ACA Marketplace to shop for plans. We tested the effect of letters and e-mails with personalized information about the savings on insurance premiums that they could realize from switching plans and the effect of generic communications that simply emphasized the possibility of saving. The personalized and generic messages both increased shopping on the Marketplace's website by 23 percent, but neither type of message had a significant effect on plan switching. These findings show that simple "nudges" with even generic information can promote shopping in health insurance marketplaces, but whether they can lead to switching remains an open question. Project HOPE—The People-to-People Health Foundation, Inc.

Zinc-chlorine battery plant system and method

DOEpatents

Whittlesey, Curtis C.; Mashikian, Matthew S.

1981-01-01

A zinc-chlorine battery plant system and method of redirecting the electrical current around a failed battery module. The battery plant includes a power conditioning unit, a plurality of battery modules connected electrically in series to form battery strings, a plurality of battery strings electrically connected in parallel to the power conditioning unit, and a bypass switch for each battery module in the battery plant. The bypass switch includes a normally open main contact across the power terminals of the battery module, and a set of normally closed auxiliary contacts for controlling the supply of reactants electrochemically transformed in the cells of the battery module. Upon the determination of a failure condition, the bypass switch for the failed battery module is energized to close the main contact and open the auxiliary contacts. Within a short time, the electrical current through the battery module will substantially decrease due to the cutoff of the supply of reactants, and the electrical current flow through the battery string will be redirected through the main contact of the bypass switch.

Reliability analysis of component-level redundant topologies for solid-state fault current limiter

NASA Astrophysics Data System (ADS)

Farhadi, Masoud; Abapour, Mehdi; Mohammadi-Ivatloo, Behnam

2018-04-01

Experience shows that semiconductor switches in power electronics systems are the most vulnerable components. One of the most common ways to solve this reliability challenge is component-level redundant design. There are four possible configurations for the redundant design in component level. This article presents a comparative reliability analysis between different component-level redundant designs for solid-state fault current limiter. The aim of the proposed analysis is to determine the more reliable component-level redundant configuration. The mean time to failure (MTTF) is used as the reliability parameter. Considering both fault types (open circuit and short circuit), the MTTFs of different configurations are calculated. It is demonstrated that more reliable configuration depends on the junction temperature of the semiconductor switches in the steady state. That junction temperature is a function of (i) ambient temperature, (ii) power loss of the semiconductor switch and (iii) thermal resistance of heat sink. Also, results' sensitivity to each parameter is investigated. The results show that in different conditions, various configurations have higher reliability. The experimental results are presented to clarify the theory and feasibility of the proposed approaches. At last, levelised costs of different configurations are analysed for a fair comparison.

Phenotypic states become increasingly sensitive to perturbations near a bifurcation in a synthetic gene network

PubMed Central

Axelrod, Kevin; Sanchez, Alvaro; Gore, Jeff

2015-01-01

Microorganisms often exhibit a history-dependent phenotypic response after exposure to a stimulus which can be imperative for proper function. However, cells frequently experience unexpected environmental perturbations that might induce phenotypic switching. How cells maintain phenotypic states in the face of environmental fluctuations remains an open question. Here, we use environmental perturbations to characterize the resilience of phenotypic states in a synthetic gene network near a critical transition. We find that far from the critical transition an environmental perturbation may induce little to no phenotypic switching, whereas close to the critical transition the same perturbation can cause many cells to switch phenotypic states. This loss of resilience was observed for perturbations that interact directly with the gene circuit as well as for a variety of generic perturbations-such as salt, ethanol, or temperature shocks-that alter the state of the cell more broadly. We obtain qualitatively similar findings in natural gene circuits, such as the yeast GAL network. Our findings illustrate how phenotypic memory can become destabilized by environmental variability near a critical transition. DOI: http://dx.doi.org/10.7554/eLife.07935.001 PMID:26302311

Atomic Processes in a Plasma Opening Switch.

NASA Astrophysics Data System (ADS)

Klepper, C. C.; Moschella, J. J.; Hazelton, R. C.; Yadlowsky, E. J.; Maron, Y.

1998-11-01

Detailed measurements of carbon emission have been carried out in a Plasma Opening Switch (POS) with a planar geometry, in order to characterize the plasma conditions and the ionization process in the POS. Emission from various transitions of C^circ to C^3+ has been measured as a function of time from several viewing chords. For these experiments, the POS was operated with a shorted load at 130kA and with a ~700ns conduction time. A single-chord, heterodyne interferometer measured the electron density evolution along a chord coincident with one of the spectroscopic views. The passage of the ionization front across the line of sight is witnessed by both diagnostics. The data are interpreted by analyzing the time-dependent atomic processes. The measured ne rises from 1.5×10^15 to 3×10^15cm-3 as the current crosses the view. An initial electron temperature in the 1.3-2 eV range is obtained from the ratio of the C II 4267 Åand 6578 Ålines. The time dependent line emission of the various charge states shows that Te rises to a few tens of eV at the peak current. The charge state distribution during the pulse will be discussed.

Asymmetric Switch Costs in Numeral Naming and Number Word Reading: Implications for Models of Bilingual Language Production.

PubMed

Reynolds, Michael G; Schlöffel, Sophie; Peressotti, Francesca

2015-01-01

One approach used to gain insight into the processes underlying bilingual language comprehension and production examines the costs that arise from switching languages. For unbalanced bilinguals, asymmetric switch costs are reported in speech production, where the switch cost for L1 is larger than the switch cost for L2, whereas, symmetric switch costs are reported in language comprehension tasks, where the cost of switching is the same for L1 and L2. Presently, it is unclear why asymmetric switch costs are observed in speech production, but not in language comprehension. Three experiments are reported that simultaneously examine methodological explanations of task related differences in the switch cost asymmetry and the predictions of three accounts of the switch cost asymmetry in speech production. The results of these experiments suggest that (1) the type of language task (comprehension vs. production) determines whether an asymmetric switch cost is observed and (2) at least some of the switch cost asymmetry arises within the language system.

Asymmetric Switch Costs in Numeral Naming and Number Word Reading: Implications for Models of Bilingual Language Production

PubMed Central

Reynolds, Michael G.; Schlöffel, Sophie; Peressotti, Francesca

2016-01-01

One approach used to gain insight into the processes underlying bilingual language comprehension and production examines the costs that arise from switching languages. For unbalanced bilinguals, asymmetric switch costs are reported in speech production, where the switch cost for L1 is larger than the switch cost for L2, whereas, symmetric switch costs are reported in language comprehension tasks, where the cost of switching is the same for L1 and L2. Presently, it is unclear why asymmetric switch costs are observed in speech production, but not in language comprehension. Three experiments are reported that simultaneously examine methodological explanations of task related differences in the switch cost asymmetry and the predictions of three accounts of the switch cost asymmetry in speech production. The results of these experiments suggest that (1) the type of language task (comprehension vs. production) determines whether an asymmetric switch cost is observed and (2) at least some of the switch cost asymmetry arises within the language system. PMID:26834659

Balloon-Supported Loran Antenna, New Hardware for Tethered Balloons, and Payloads Used in BAMM Flights.

DTIC Science & Technology

1980-02-28

containing a command receiver, batteries, and a differential- pressure switch , all located immediately below the confluence point, with long leads and a...should break free, or during normal deflation at take- down. Purpose of the differential- pressure switch was to momentarily open the valves if the...otherwise was completely different. A differential- pressure switch of the type formerly used in the command package, but without the long pressure

Development of a 30mm Frangible Projectile Crimper

DTIC Science & Technology

1977-02-01

located at end of tank. Open drain valve to drain condensation Tht outomatic lank drain equipped compressor makes this unnecessary. PRESSURE SWITCH : The... pressure switch is automatic and will start compressor at the low pressure and stop when the maximum pressure is leached. It is adjusted to start...of the check valve, located between the compressor and the tank, together with the relief valve on pressure switch relief valve units, and the cen

Performance Comparison of SDN Solutions for Switching Dedicated Long-Haul Connections

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rao, Nageswara S

2016-01-01

We consider scenarios with two sites connected over a dedicated, long-haul connection that must quickly fail-over in response to degradations in host-to-host application performance. We present two methods for path fail-over using OpenFlowenabled switches: (a) a light-weight method that utilizes host scripts to monitor the application performance and dpctl API for switching, and (b) a generic method that uses two OpenDaylight (ODL) controllers and REST interfaces. The restoration dynamics of the application contain significant statistical variations due to the controllers, north interfaces and switches; in addition, the variety of vendor implementations further complicates the choice between different solutions. We presentmore » the impulse-response method to estimate the regressions of performance parameters, which enables a rigorous and objective comparison of different solutions. We describe testing results of the two methods, using TCP throughput and connection rtt as main parameters, over a testbed consisting of HP and Cisco switches connected over longhaul connections emulated in hardware by ANUE devices. The combination of analytical and experimental results demonstrates that dpctl method responds seconds faster than ODL method on average, while both methods restore TCP throughput.« less

Influence of oxygen doping on resistive-switching characteristic of a-Si/c-Si device

NASA Astrophysics Data System (ADS)

Zhang, Jiahua; Chen, Da; Huang, Shihua

2017-12-01

The influence of oxygen doping on resistive-switching characteristics of Ag/a-Si/p+-c-Si device was investigated. By oxygen doping in the growth process of amorphous silicon, the device resistive-switching performances, such as the ON/OFF resistance ratios, yield and stability were improved, which may be ascribed to the significant reduction of defect density because of oxygen incorporation. The device I-V characteristics are strongly dependent on the oxygen doping concentration. As the oxygen doping concentration increases, the Si-rich device gradually transforms to an oxygen-rich device, and the device yield, switching characteristics, and stability may be improved for silver/oxygen-doped a-Si/p+-c-Si device. Finally, the device resistive-switching mechanism was analyzed. Project supported by the Zhejiang Provincial Natural Science Foundation of China (No. LY17F040001), the Open Project Program of Surface Physics Laboratory (National Key Laboratory) of Fudan University (No. KF2015_02), the Open Project Program of National Laboratory for Infrared Physics, Chinese Academy of Sciences (No. M201503), the Zhejiang Provincial Science and Technology Key Innovation Team (No. 2011R50012), and the Zhejiang Provincial Key Laboratory (No. 2013E10022).

Control of a nursing bed based on a hybrid brain-computer interface.

PubMed

Nengneng Peng; Rui Zhang; Haihua Zeng; Fei Wang; Kai Li; Yuanqing Li; Xiaobin Zhuang

2016-08-01

In this paper, we propose an intelligent nursing bed system which is controlled by a hybrid brain-computer interface (BCI) involving steady-state visual evoked potential (SSVEP) and P300. Specifically, the hybrid BCI includes an asynchronous brain switch based on SSVEP and P300, and a P300-based BCI. The brain switch is used to turn on/off the control system of the electric nursing bed through idle/control state detection, whereas the P300-based BCI is for operating the nursing bed. At the beginning, the user may focus on one group of flashing buttons in the graphic user interface (GUI) of the brain switch, which can simultaneously evoke SSVEP and P300, to switch on the control system. Here, the combination of SSVEP and P300 is used for improving the performance of the brain switch. Next, the user can control the nursing bed using the P300-based BCI. The GUI of the P300-based BCI includes 10 flashing buttons, which correspond to 10 functional operations, namely, left-side up, left-side down, back up, back down, bedpan open, bedpan close, legs up, legs down, right-side up, and right-side down. For instance, he/she can focus on the flashing button "back up" in the GUI of the P300-based BCI to activate the corresponding control such that the nursing bed is adjusted up. Eight healthy subjects participated in our experiment, and obtained an average accuracy of 93.75% and an average false positive rate (FPR) of 0.15 event/min. The effectiveness of our system was thus demonstrated.

The effect of working gas pressure on the switching rate of a kivotron

NASA Astrophysics Data System (ADS)

Bokhan, P. A.; Gugin, P. P.; Zakrevsky, D. E.; Lavrukhin, M. A.

2016-05-01

The switching rate in gas-discharge devices (kivotrons) based on an "open" discharge with counterpropagating electron beams is studied experimentally. Structures with a total cathode area of 2 cm2 were used. A monotonic reduction in the switching time with an increase in the working gas pressure and in the voltage amplitude at the time of breakdown is demonstrated. The minimum switching time is ~240 ps at a voltage of 17 kV. The maximum current rise rate, which is limited by the discharge circuit inductance, is 3 × 1012 A/s.

Ultrafast Coherent Dynamics of a Photonic Crystal All-Optical Switch.

PubMed

Colman, Pierre; Lunnemann, Per; Yu, Yi; Mørk, Jesper

2016-12-02

We present pump-probe measurements of an all-optical photonic crystal switch based on a nanocavity, resolving fast coherent temporal dynamics. The measurements demonstrate the importance of coherent effects typically neglected when considering nanocavity dynamics. In particular, we report the observation of an idler pulse and more than 10 dB parametric gain. The measurements are in good agreement with a theoretical model that ascribes the observation to oscillations of the free-carrier population in the nanocavity. The effect opens perspectives for the realization of new all-optical photonic crystal switches with unprecedented switching contrast.

Experience with code-switching modulates the use of grammatical gender during sentence processing

PubMed Central

Valdés Kroff, Jorge R.; Dussias, Paola E.; Gerfen, Chip; Perrotti, Lauren; Bajo, M. Teresa

2016-01-01

Using code-switching as a tool to illustrate how language experience modulates comprehension, the visual world paradigm was employed to examine the extent to which gender-marked Spanish determiners facilitate upcoming target nouns in a group of Spanish-English bilingual code-switchers. The first experiment tested target Spanish nouns embedded in a carrier phrase (Experiment 1b) and included a control Spanish monolingual group (Experiment 1a). The second set of experiments included critical trials in which participants heard code-switches from Spanish determiners into English nouns (e.g., la house) either in a fixed carrier phrase (Experiment 2a) or in variable and complex sentences (Experiment 2b). Across the experiments, bilinguals revealed an asymmetric gender effect in processing, showing facilitation only for feminine target items. These results reflect the asymmetric use of gender in the production of code-switched speech. The extension of the asymmetric effect into Spanish (Experiment 1b) underscores the permeability between language modes in bilingual code-switchers. PMID:28663771

Development of Simulated Disturbing Source for Isolation Switch

NASA Astrophysics Data System (ADS)

Cheng, Lin; Liu, Xiang; Deng, Xiaoping; Pan, Zhezhe; Zhou, Hang; Zhu, Yong

2018-01-01

In order to simulate the substation in the actual scene of the harsh electromagnetic environment, and then research on electromagnetic compatibility testing of electronic instrument transformer, On the basis of the original isolation switch as a harassment source of the electronic instrument transformer electromagnetic compatibility test system, an isolated switch simulation source system was developed, to promote the standardization of the original test. In this paper, the circuit breaker is used to control the opening and closing of the gap arc to simulate the operating of isolating switch, and the isolation switch simulation harassment source system is designed accordingly. Comparison with the actual test results of the isolating switch, it is proved that the system can meet the test requirements, and the simulation harassment source system has good stability and high reliability.

The framing effect in a monetary gambling task is robust in minimally verbal language switching contexts.

PubMed

Korn, Christoph W; Heekeren, Hauke R; Oganian, Yulia

2018-04-01

Decision-making biases, in particular the framing effect, can be altered in foreign language settings (foreign language effect) and following switching between languages (the language switching effect on framing). Recently, it has been suggested that the framing effect is only affected by foreign language use if the task is presented in a rich textual form. Here, we assess whether an elaborate verbal task is also a prerequisite for the language switching effect on framing. We employed a financial gambling task that induces a robust framing effect but is less verbal than the classical framing paradigms (e.g., the Asian disease problem). We conducted an online experiment ( n = 485), where we orthogonally manipulated language use and language switching between trials. The results showed no effects of foreign language use or language switching throughout the experiment. This online result was confirmed in a laboratory experiment ( n = 27). Overall, we find that language switching does not reduce the framing effect in a paradigm with little verbal content and thus that language switching effects seem contingent on the amount of verbal processing required.

Feature Integration and Task Switching: Diminished Switch Costs after Controlling for Stimulus, Response, and Cue Repetitions

PubMed Central

Schmidt, James R.; Liefooghe, Baptist

2016-01-01

This report presents data from two versions of the task switching procedure in which the separate influence of stimulus repetitions, response key repetitions, conceptual response repetitions, cue repetitions, task repetitions, and congruency are considered. Experiment 1 used a simple alternating runs procedure with parity judgments of digits and consonant/vowel decisions of letters as the two tasks. Results revealed sizable effects of stimulus and response repetitions, and controlling for these effects reduced the switch cost. Experiment 2 was a cued version of the task switch paradigm with parity and magnitude judgments of digits as the two tasks. Results again revealed large effects of stimulus and response repetitions, in addition to cue repetition effects. Controlling for these effects again reduced the switch cost. Congruency did not interact with our novel “unbiased” measure of switch costs. We discuss how the task switch paradigm might be thought of as a more complex version of the feature integration paradigm and propose an episodic learning account of the effect. We further consider to what extent appeals to higher-order control processes might be unnecessary and propose that controls for feature integration biases should be standard practice in task switching experiments. PMID:26964102

High-Voltage, High-Power Gaseous Electronics Switch For Electric Grid Power Conversion

NASA Astrophysics Data System (ADS)

Sommerer, Timothy J.

2014-05-01

We are developing a high-voltage, high-power gas switch for use in low-cost power conversion terminals on the electric power grid. Direct-current (dc) power transmission has many advantages over alternating current (ac) transmission, but at present the high cost of ac-dc power interconversion limits the use of dc. The gas switch we are developing conducts current through a magnetized cold cathode plasma in hydrogen or helium to reach practical current densities > 1 A/cm2. Thermal and sputter damage of the cathode by the incident ion flux is a major technical risk, and is being addressed through use of a ``self-healing'' liquid metal cathode (eg, gallium). Plasma conditions and cathode sputtering loss are estimated by analyzing plasma spectral emission. A particle-in-cell plasma model is used to understand various aspects of switch operation, including the conduction phase (where plasma densities can exceed 1013 cm-3), the switch-open phase (where the high-voltage must be held against gas breakdown on the left side of Paschen's curve), and the switching transitions (especially the opening process, which is initiated by forming an ion-matrix sheath adjacent to a control grid). The information, data, or work presented herein was funded in part by the Advanced Research Projects Agency-Energy (ARPA-E), U.S. Department of Energy, under Award Number DE-AR0000298.

What’s Easier: Doing What You Want, or Being Told What to Do? Cued versus Voluntary Language and Task Switching

PubMed Central

Gollan, Tamar H.; Kleinman, Daniel; Wierenga, Christina E.

2014-01-01

The current study contrasted cued versus voluntary switching to investigate switching efficiency and possible sharing of control mechanisms across linguistic and non-linguistic domains. Bilinguals switched between naming pictures in Spanish versus English or between reading numbers aloud versus adding their digits, either without or with repetition of stimuli, and with fewer requirements as to when and how much they had to switch relative to previous instantiations of voluntary switching. Without repetition (Experiment 1), voluntary responses were faster than cued responses on both stay and switch trials (especially in the non-linguistic switching task), whereas in previous studies the voluntary advantage was restricted to switch-cost reduction. Similarly, when targets were presented repeatedly (Experiment 2), voluntary responses were faster overall for both linguistic and non-linguistic switching, though here the advantage tended to be larger on switch trials. Experiment 3 confirmed the overall voluntary speed advantage for the read-add task in monolinguals, and revealed a reduction in switch costs only for a different non-linguistic task (size-parity judgments). These results reveal greater overall advantages for voluntary over cued switching than previously reported, but also that the precise manifestation of the voluntary advantage can vary with different tasks. In the linguistic domain, lexical inaccessibility introduces some unique control mechanisms, and repetition may magnify cross-domain overlap in control mechanisms. Finally, under some limited conditions, cost-free switches were found in both linguistic and non-linguistic domains; however, suspension of top-down control may be restricted to language or highly automatic tasks. PMID:25313951

Switch failure diagnosis based on inductor current observation for boost converters

NASA Astrophysics Data System (ADS)

Jamshidpour, E.; Poure, P.; Saadate, S.

2016-09-01

Face to the growing number of applications using DC-DC power converters, the improvement of their reliability is subject to an increasing number of studies. Especially in safety critical applications, designing fault-tolerant converters is becoming mandatory. In this paper, a switch fault-tolerant DC-DC converter is studied. First, some of the fastest Fault Detection Algorithms (FDAs) are recalled. Then, a fast switch FDA is proposed which can detect both types of failures; open circuit fault as well as short circuit fault can be detected in less than one switching period. Second, a fault-tolerant converter which can be reconfigured under those types of fault is introduced. Hardware-In-the-Loop (HIL) results and experimental validations are given to verify the validity of the proposed switch fault-tolerant approach in the case of a single switch DC-DC boost converter with one redundant switch.

Achievement of controlled resistive response of nanogapped palladium film to hydrogen

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, M.; Wong, M. H.; Ong, C. W., E-mail: c.w.ong@polyu.edu.hk

2015-07-20

Palladium (Pd) film containing nanogaps of well controlled dimension was fabricated on a Si wafer having a high-aspect-ratio micropillar. The Pd film was arranged to experience hydrogen (H{sub 2})-induced volume expansion. (i) If the nanogap is kept open, its width is narrowed down. A discharge current was generated to give a strong, fast, and repeatable on-off type resistive switching response. (ii) If the nanogap is closed, the cross section of the conduction path varies to give continuous H{sub 2}-concentration dependent resistive response. The influence of stresses and related physical mechanisms are discussed.

Roles of context in acquisition of human instrumental learning: Implications for the understanding of the mechanisms underlying context-switch effects.

PubMed

Gámez, A Matías; León, Samuel P; Rosas, Juan M

2017-09-01

Four experiments in human instrumental learning explored the associations involving the context that develop after three trials of training on simple discriminations. Experiments 1 and 4 found a deleterious effect of switching the learning context that cannot be explained by the context-outcome binary associations commonly used to explain context-switch effects after short training in human predictive learning and in animal Pavlovian conditioning. Evidence for context-outcome (Experiment 2), context-discriminative stimulus (Experiment 3), and context-instrumental response (Experiment 4) binary associations was found within the same training paradigm, suggesting that contexts became associated with all the elements of the situation, regardless of whether those associations played a role in a specific context-switch effect detected on performance.

Form Overrides Meaning When Bilinguals Monitor for Errors

PubMed Central

Ivanova, Iva; Ferreira, Victor S.; Gollan, Tamar H.

2016-01-01

Bilinguals rarely produce unintended language switches, which may in part be because switches are detected and corrected by an internal monitor. But are language switches easier or harder to detect than within-language semantic errors? To approximate internal monitoring, bilinguals listened (Experiment 1) or read aloud (Experiment 2) stories, and detected language switches (translation equivalents or semantically unrelated to expected words) and within-language errors (semantically related or unrelated to expected words). Bilinguals detected semantically related within-language errors most slowly and least accurately, language switches more quickly and accurately than within-language errors, and (in Experiment 2), translation equivalents as quickly and accurately as unrelated language switches. These results suggest that internal monitoring of form (which can detect mismatches in language membership) completes earlier than, and is independent of, monitoring of meaning. However, analysis of reading times prior to error detection revealed meaning violations to be more disruptive for processing than language violations. PMID:28649169

Effects of aripiprazole once-monthly on symptoms of schizophrenia in patients switched from oral antipsychotics.

PubMed

Peters-Strickland, Timothy; Zhao, Cathy; Perry, Pamela P; Eramo, Anna; Salzman, Phyllis M; McQuade, Robert D; Johnson, Brian R; Sanchez, Raymond

2016-12-01

To assess the effects of aripiprazole once-monthly 400 mg (AOM 400) on clinical symptoms and global improvement in schizophrenia after switching from an oral antipsychotic. In a multicenter, open-label, mirror-image, naturalistic study in patients with schizophrenia (>1 year, Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision [DSM-IV-TR] criteria), changes in efficacy measures were assessed during prospective treatment (6 months) with AOM 400 after switching from standard-of-care oral antipsychotics. During prospective treatment, patients were cross-titrated to oral aripiprazole monotherapy (1-4) weeks followed by open-label AOM 400 (24 weeks). Mean change from baseline of the open-label AOM 400 phase in Positive and Negative Syndrome Scale (PANSS) scores (total, positive and negative subscales) and Clinical Global Impression-Severity (CGI-S) scores; mean CGI-Improvement (CGI-I) score; and proportion of responders (≥30% decrease from baseline in PANSS total score or CGI-I score of 1 [very much improved] or 2 [much improved]) were assessed. PANSS and CGI-S scores improved from baseline (P<0.0001) and CGI-I demonstrated improvement at all time points. By the end of the study, 49.0% of patients were PANSS or CGI-I responders. In a community setting, patients with schizophrenia who were stabilized at baseline and switched to AOM 400 from oral antipsychotics showed clear improvements in clinical symptoms.

Electrochemical control of a DNA Holliday Junction nanoswitch by Mg2+ ions.

PubMed

Ferapontova, E E; Mountford, C P; Crain, J; Buck, A H; Dickinson, P; Beattie, J S; Ghazal, P; Terry, J G; Walton, A J; Mount, A R

2008-11-15

The molecular conformation of a synthetic branched, 4-way DNA Holliday junction (HJ) was electrochemically switched between the open and closed (stacked) conformers. Switching was achieved by electrochemically induced quantitative release of Mg(2+) ions from the oxidised poly(N-methylpyrrole) film (PPy), which contained polyacrylate as an immobile counter anion and Mg(2+) ions as charge compensating mobile cations. This increase in the Mg(2+) concentration screened the electrostatic repulsion between the widely separated arms in the open HJ configuration, inducing switching to the closed conformation. Upon electrochemical reduction of PPy, entrapment of Mg(2+) ions back into the PPy film induced the reverse HJ switching from the closed to open state. The conformational transition was monitored using fluorescence resonance energy transfer (FRET) between donor and acceptor dyes each located at the terminus of one of the arms. The demonstrated electrochemical control of the conformation of the used probe-target HJ complex, previously reported as a highly sequence specific nanodevice for detecting of unlabelled target [Buck, A.H., Campbell, C.J., Dickinson, P., Mountford, C.P., Stoquert, H.C., Terry, J.G., Evans, S.A.G., Keane, L., Su, T.J., Mount, A.R., Walton, A.J., Beattie, J.S., Crain, J., Ghazal, P., 2007. Anal. Chem., 79, 4724-4728], allows the development of electronically addressable DNA nanodevices and label-free gene detection assays.

Light-weight DC to very high voltage DC converter

DOEpatents

Druce, Robert L.; Kirbie, Hugh C.; Newton, Mark A.

1998-01-01

A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current.

Stimulus-level interference disrupts repetition benefit during task switching in middle childhood

PubMed Central

Karayanidis, Frini; Jamadar, Sharna; Sanday, Dearne

2013-01-01

The task-switching paradigm provides a powerful tool to measure the development of core cognitive control processes. In this study, we use the alternating runs task-switching paradigm to assess preparatory control processes involved in flexibly preparing for a predictable change in task and stimulus-driven control processes involved in controlling stimulus-level interference. We present three experiments that examine behavioral and event-related potential (ERP) measures of task-switching performance in middle childhood and young adulthood under low and high stimulus interference conditions. Experiment 1 confirms that our new child-friendly tasks produce similar behavioral and electrophysiological findings in young adults as those previously reported. Experiment 2 examines task switching with univalent stimuli across a range of preparation intervals in middle childhood. Experiment 3 compares task switching with bivalent stimuli across the same preparation intervals in children and young adults. Children produced a larger RT switch cost than adults with univalent stimuli and a short preparation interval. Both children and adults showed significant reduction in switch cost with increasing preparation interval, but in children this was caused by greater increase in RT for repeat than switch trials. Response-locked ERPs showed intact preparation for univalent, but less efficient preparation for bivalent stimulus conditions. Stimulus-locked ERPs confirmed that children showed greater stimulus-level interference for repeat trials, especially with bivalent stimuli. We conclude that children show greater stimulus-level interference especially for repeat trials under high interference conditions, suggesting weaker mental representation of the current task set. PMID:24367317

[Open door intensive care unit: perspective of the professionals].

PubMed

Ayllón Garrido, N; Montero Rus, P; Acebes Fernández, M I; Sánchez Zugazua, J

2014-01-01

Restrictive visiting hours continue to predominate at most intensive care units (ICU). Maintaining the current visiting policy or switching to an open visiting hours policy continues to be a controversial study for the staff. To know the staff perspective on the effects of open visiting hours on patients, family and professional activity. To gather proposals in order to modify the current visiting policy. A 30-item 'Likert-type scale' data was administered to ICU doctors, nurses and health care assistants of Alava University Hospital. Data was collected within an Excel database and analyzed using SPSS 19.0. Frequencies and percentages were calculated for descriptive statistics purposes and the Chi Square test was used for the bivariate analysis related to age, professional category and years of experience. The staff (n=64) considered that open visiting hours could have a beneficial effect on patients (67%) and relatives (61%). However, 62% considered that open visiting hours would be of little benefit for the staff themselves. Neither the experience of the respondent nor their professional category seem to have any statistical effect on the perception of the benefit of open visiting hours. However, the younger staff members consider open visiting hours would be more beneficial for the patient (p=.024). A total of 50% of surveyed staff would maintain the current visiting hours and would extend them if required by the patient's condition. Staff members continue to consider the current, restricted visiting policy to be the most appropriate option for the unit. However, they accept the possibility of extending visiting hours for particular cases if beneficial for the patient. Copyright © 2013 Elsevier España, S.L. y SEEIUC. All rights reserved.

30 CFR 18.48 - Circuit-interrupting devices.

Code of Federal Regulations, 2011 CFR

2011-07-01

... two-pole switch of the “dead-man-control” type that must be held closed by hand and will open when hand pressure is released. (e) A machine designed to operate from both trolley wire and portable cable.... Such a switch shall be designed to prevent electrical connection to the machine frame when the cable is...

30 CFR 18.48 - Circuit-interrupting devices.

Code of Federal Regulations, 2013 CFR

2013-07-01

... two-pole switch of the “dead-man-control” type that must be held closed by hand and will open when hand pressure is released. (e) A machine designed to operate from both trolley wire and portable cable.... Such a switch shall be designed to prevent electrical connection to the machine frame when the cable is...

47 CFR 15.231 - Periodic operation in the band 40.66-40.70 MHz and above 70 MHz.

Code of Federal Regulations, 2010 CFR

2010-10-01

... from intentional radiators operated under this section shall not exceed the following: Fundamental... signal such as those used with alarm systems, door openers, remote switches, etc. Continuous... operation: (1) A manually operated transmitter shall employ a switch that will automatically deactivate the...

Reversible optical switching memristors with tunable STDP synaptic plasticity: a route to hierarchical control in artificial intelligent systems.

PubMed

Jaafar, Ayoub H; Gray, Robert J; Verrelli, Emanuele; O'Neill, Mary; Kelly, Stephen M; Kemp, Neil T

2017-11-09

Optical control of memristors opens the route to new applications in optoelectronic switching and neuromorphic computing. Motivated by the need for reversible and latched optical switching we report on the development of a memristor with electronic properties tunable and switchable by wavelength and polarization specific light. The device consists of an optically active azobenzene polymer, poly(disperse red 1 acrylate), overlaying a forest of vertically aligned ZnO nanorods. Illumination induces trans-cis isomerization of the azobenzene molecules, which expands or contracts the polymer layer and alters the resistance of the off/on states, their ratio and retention time. The reversible optical effect enables dynamic control of a memristor's learning properties including control of synaptic potentiation and depression, optical switching between short-term and long-term memory and optical modulation of the synaptic efficacy via spike timing dependent plasticity. The work opens the route to the dynamic patterning of memristor networks both spatially and temporally by light, thus allowing the development of new optically reconfigurable neural networks and adaptive electronic circuits.

Fast infrared response of YBCO thin films

NASA Technical Reports Server (NTRS)

Ballentine, P. H.; Kadin, A. M.; Donaldson, W. R.; Scofield, J. H.; Bajuk, L.

1990-01-01

The response to short infrared pulses of some epitaxial YBCO films prepared by sputter deposition and by electron-beam evaporation is reported. The response is found to be essentially bolometric on the ns timescale, with some indirect hints of nonequilibrium electron transport on the ps scale. Fast switching could be obtained either by biasing the switch close to the critical current or by cooling the film below about 20 K. These results are encouraging for potential application to a high-current optically-triggered opening switch.

Analysis and Evaluation of German Attainments and Research in the Liquid Rocket Engine Field. Volume 8. Rocket Engine Control and Safety Circuits

DTIC Science & Technology

1951-02-01

the pressure switch (16) is activated. This causes the-electrical circuit to open valve (11) and start the igniter (17). The nitrogen pressure...activates the pressure switch (11) at approximately 7 psi before it flows through the Injector (9) into the chamber. ATI-85«’󈧕 - -A 11...precluded. Accordingly, pressure switch (11) is inserted in the system in parallel (electrically) with the flow indicator (17), and the circuit may

Plasma Switch Development.

DTIC Science & Technology

1984-06-08

Appendix II), the progress to date will be detailed here. II° K -BEAM CONTROLLED SWITCH The EBCS is an opening switch concept that has the potential for...such plasma in ᝺ uis. To accurately assess the viability of this scheme, more effort than what was provided to date is required. 0 00 LL k CCj2 E - w...1962 e+A* -A +A (2) ... 2OOOz t~ -- whs A is, in enera, any positive molecular ion (simple or cluster ) of species A. We define the effective rate at

Hybrid high direct current circuit interrupter

DOEpatents

Rockot, Joseph H.; Mikesell, Harvey E.; Jha, Kamal N.

1998-01-01

A device and a method for interrupting very high direct currents (greater than 100,000 amperes) and simultaneously blocking high voltages (greater than 600 volts). The device utilizes a mechanical switch to carry very high currents continuously with low loss and a silicon controlled rectifier (SCR) to bypass the current around the mechanical switch while its contacts are separating. A commutation circuit, connected in parallel with the SCR, turns off the SCR by utilizing a resonant circuit to divert the SCR current after the switch opens.

Voltage control in pulsed system by predict-ahead control

DOEpatents

Payne, Anthony N.; Watson, James A.; Sampayan, Stephen E.

1994-01-01

A method and apparatus for predict-ahead pulse-to-pulse voltage control in a pulsed power supply system is disclosed. A DC power supply network is coupled to a resonant charging network via a first switch. The resonant charging network is coupled at a node to a storage capacitor. An output load is coupled to the storage capacitor via a second switch. A de-Q-ing network is coupled to the resonant charging network via a third switch. The trigger for the third switch is a derived function of the initial voltage of the power supply network, the initial voltage of the storage capacitor, and the present voltage of the storage capacitor. A first trigger closes the first switch and charges the capacitor. The third trigger is asserted according to the derived function to close the third switch. When the third switch is closed, the first switch opens and voltage on the node is regulated. The second trigger may be thereafter asserted to discharge the capacitor into the output load.

Voltage control in pulsed system by predict-ahead control

DOEpatents

Payne, A.N.; Watson, J.A.; Sampayan, S.E.

1994-09-13

A method and apparatus for predict-ahead pulse-to-pulse voltage control in a pulsed power supply system is disclosed. A DC power supply network is coupled to a resonant charging network via a first switch. The resonant charging network is coupled at a node to a storage capacitor. An output load is coupled to the storage capacitor via a second switch. A de-Q-ing network is coupled to the resonant charging network via a third switch. The trigger for the third switch is a derived function of the initial voltage of the power supply network, the initial voltage of the storage capacitor, and the present voltage of the storage capacitor. A first trigger closes the first switch and charges the capacitor. The third trigger is asserted according to the derived function to close the third switch. When the third switch is closed, the first switch opens and voltage on the node is regulated. The second trigger may be thereafter asserted to discharge the capacitor into the output load. 4 figs.

Coexistence of diode-like volatile and multilevel nonvolatile resistive switching in a ZrO2/TiO2 stack structure.

PubMed

Li, Yingtao; Yuan, Peng; Fu, Liping; Li, Rongrong; Gao, Xiaoping; Tao, Chunlan

2015-10-02

Diode-like volatile resistive switching as well as nonvolatile resistive switching behaviors in a Cu/ZrO₂/TiO₂/Ti stack are investigated. Depending on the current compliance during the electroforming process, either volatile resistive switching or nonvolatile resistive switching is observed. With a lower current compliance (<10 μA), the Cu/ZrO₂/TiO₂/Ti device exhibits diode-like volatile resistive switching with a rectifying ratio over 10(6). The permanent transition from volatile to nonvolatile resistive switching can be obtained by applying a higher current compliance of 100 μA. Furthermore, by using different reset voltages, the Cu/ZrO₂/TiO₂/Ti device exhibits multilevel memory characteristics with high uniformity. The coexistence of nonvolatile multilevel memory and diode-like volatile resistive switching behaviors in the same Cu/ZrO₂/TiO₂/Ti device opens areas of applications in high-density storage, logic circuits, neural networks, and passive crossbar memory selectors.

62. VIEW LOOKING NORTHWEST AT THE OIL FILLED CIRCUIT BREAKER ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

62. VIEW LOOKING NORTHWEST AT THE OIL FILLED CIRCUIT BREAKER FOR GENERATOR NUMBER 1. CIRCUIT BREAKERS ARE AUTOMATED SWITCHES WHICH DISCONNECT THE GENERATORS FROM THE LINE WHEN SHORT CIRCUITS OCCUR. WHEN CIRCUITS INVOLVING HIGH CURRENTS AND VOLTAGES ARE BROKEN, THE AIR SURROUNDING MECHANICAL PARTS OF THE SWITCH BECOMES IONIZED AND CONTINUES TO CONDUCT ELECTRIC POWER ACROSS ANY GAP IN THE SWITCH CONTACTS. TO PREVENT THIS AND INSURE A POSITIVE INTERRUPTION OF CURRENT, THE SWITCH CONTACTS ARE IMMERSED IN A CONTAINER OF OIL. THE OIL DOES NOT SUPPORT THE FORMATION OF AN ARC AND EFFECTIVELY CUTS OFF THE CURRENT WHEN THE SWITCH CONTACTS ARE OPENED. - New York, New Haven & Hartford Railroad, Cos Cob Power Plant, Sound Shore Drive, Greenwich, Fairfield County, CT

The influence of visual feedback from the recent past on the programming of grip aperture is grasp-specific, shared between hands, and mediated by sensorimotor memory not task set.

PubMed

Tang, Rixin; Whitwell, Robert L; Goodale, Melvyn A

2015-05-01

Goal-directed movements, such as reaching out to grasp an object, are necessarily constrained by the spatial properties of the target such as its size, shape, and position. For example, during a reach-to-grasp movement, the peak width of the aperture formed by the thumb and fingers in flight (peak grip aperture, PGA) is linearly related to the target's size. Suppressing vision throughout the movement (visual open loop) has a small though significant effect on this relationship. Visual open loop conditions also produce a large increase in the PGA compared to when vision is available throughout the movement (visual closed loop). Curiously, this differential effect of the availability of visual feedback is influenced by the presentation order: the difference in PGA between closed- and open-loop trials is smaller when these trials are intermixed (an effect we have called 'homogenization'). Thus, grasping movements are affected not only by the availability of visual feedback (closed loop or open loop) but also by what happened on the previous trial. It is not clear, however, whether this carry-over effect is mediated through motor (or sensorimotor) memory or through the interference of different task sets for closed-loop and open-loop feedback that determine when the movements are fully specified. We reasoned that sensorimotor memory, but not a task set for closed and open loop feedback, would be specific to the type of response. We tested this prediction in a condition in which pointing to targets was alternated with grasping those same targets. Critically, in this condition, when pointing was performed in open loop, grasping was always performed in closed loop (and vice versa). Despite the fact that closed- and open-loop trials were alternating in this condition, we found no evidence for homogenization of the PGA. Homogenization did occur, however, in a follow-up experiment in which grasping movements and visual feedback were alternated between the left and the right hand, indicating that sensorimotor (or motor) memory can operate both within and between hands when the response type is kept the same. In a final experiment, we ruled out the possibility that simply alternating the hand used to perform the grasp interferes with motor or sensorimotor memory. We did this by showing that when the hand was alternated within a block of exclusively closed- or open-loop trials, homogenization of the PGA did not occur. Taken together, the results suggest that (1) interference from simply switching between task sets for closed or open-loop feedback or from switching between the hands cannot account homogenization in the PGA and that (2) the programming and execution of grasps can borrow not only from grasping movements executed in the past by the same hand, but also from grasping movements executed with the other hand. Copyright © 2015 Elsevier B.V. All rights reserved.

Toward nonlinear magnonics: Intensity-dependent spin-wave switching in insulating side-coupled magnetic stripes

NASA Astrophysics Data System (ADS)

Sadovnikov, A. V.; Odintsov, S. A.; Beginin, E. N.; Sheshukova, S. E.; Sharaevskii, Yu. P.; Nikitov, S. A.

2017-10-01

We demonstrate that the nonlinear spin-wave transport in two laterally parallel magnetic stripes exhibit the intensity-dependent power exchange between the adjacent spin-wave channels. By the means of Brillouin light scattering technique, we investigate collective nonlinear spin-wave dynamics in the presence of magnetodipolar coupling. The nonlinear intensity-dependent effect reveals itself in the spin-wave mode transformation and differential nonlinear spin-wave phase shift in each adjacent magnetic stripe. The proposed analytical theory, based on the coupled Ginzburg-Landau equations, predicts the geometry design involving the reduction of power requirement to the all-magnonic switching. A very good agreement between calculation and experiment was found. In addition, a micromagnetic and finite-element approach has been independently used to study the nonlinear behavior of spin waves in adjacent stripes and the nonlinear transformation of spatial profiles of spin-wave modes. Our results show that the proposed spin-wave coupling mechanism provides the basis for nonlinear magnonic circuits and opens the perspectives for all-magnonic computing architecture.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maughan, Bret; Zahl, Percy; Sutter, Peter

Switching the magnetic properties of organic semiconductors on a metal surface has thus far largely been limited to molecule-by-molecule tip-induced transformations in scanned probe experiments. Here we demonstrate with molecular resolution that collective control of activated Kondo screening can be achieved in thin-films of the organic semiconductor titanyl phthalocyanine on Cu(110) to obtain tunable concentrations of Kondo impurities. Using low-temperature scanning tunneling microscopy and spectroscopy, we show that a thermally activated molecular distortion dramatically shifts surface–molecule coupling and enables ensemble-level control of Kondo screening in the interfacial spin system. This is accompanied by the formation of a temperature-dependent Abrikosov–Suhl–Kondo resonancemore » in the local density of states of the activated molecules. This enables coverage-dependent control over activation to the Kondo screening state. Finally, our study thus advances the versatility of molecular switching for Kondo physics and opens new avenues for scalable bottom-up tailoring of the electronic structure and magnetic texture of organic semiconductor interfaces at the nanoscale.« less

Ensemble control of Kondo screening in molecular adsorbates

DOE PAGES

Maughan, Bret; Zahl, Percy; Sutter, Peter; ...

2017-04-06

Switching the magnetic properties of organic semiconductors on a metal surface has thus far largely been limited to molecule-by-molecule tip-induced transformations in scanned probe experiments. Here we demonstrate with molecular resolution that collective control of activated Kondo screening can be achieved in thin-films of the organic semiconductor titanyl phthalocyanine on Cu(110) to obtain tunable concentrations of Kondo impurities. Using low-temperature scanning tunneling microscopy and spectroscopy, we show that a thermally activated molecular distortion dramatically shifts surface–molecule coupling and enables ensemble-level control of Kondo screening in the interfacial spin system. This is accompanied by the formation of a temperature-dependent Abrikosov–Suhl–Kondo resonancemore » in the local density of states of the activated molecules. This enables coverage-dependent control over activation to the Kondo screening state. Finally, our study thus advances the versatility of molecular switching for Kondo physics and opens new avenues for scalable bottom-up tailoring of the electronic structure and magnetic texture of organic semiconductor interfaces at the nanoscale.« less

Switching in Feedforward Control of Grip Force During Tool-Mediated Interaction With Elastic Force Fields

PubMed Central

White, Olivier; Karniel, Amir; Papaxanthis, Charalambos; Barbiero, Marie; Nisky, Ilana

2018-01-01

Switched systems are common in artificial control systems. Here, we suggest that the brain adopts a switched feedforward control of grip forces during manipulation of objects. We measured how participants modulated grip force when interacting with soft and rigid virtual objects when stiffness varied continuously between trials. We identified a sudden phase transition between two forms of feedforward control that differed in the timing of the synchronization between the anticipated load force and the applied grip force. The switch occurred several trials after a threshold stiffness level in the range 100–200 N/m. These results suggest that in the control of grip force, the brain acts as a switching control system. This opens new research questions as to the nature of the discrete state variables that drive the switching. PMID:29930504

Fast Electromechanical Switches Based on Carbon Nanotubes

NASA Technical Reports Server (NTRS)

Kaul, Anupama; Wong, Eric; Epp, Larry

2008-01-01

Electrostatically actuated nanoelectromechanical switches based on carbon nanotubes have been fabricated and tested in a continuing effort to develop high-speed switches for a variety of stationary and portable electronic equipment. As explained below, these devices offer advantages over electrostatically actuated microelectromechanical switches, which, heretofore, have represented the state of the art of rapid, highly miniaturized electromechanical switches. Potential applications for these devices include computer memories, cellular telephones, communication networks, scientific instrumentation, and general radiation-hard electronic equipment. A representative device of the present type includes a single-wall carbon nanotube suspended over a trench about 130 nm wide and 20 nm deep in an electrically insulating material. The ends of the carbon nanotube are connected to metal electrodes, denoted the source and drain electrodes. At bottom of the trench is another metal electrode, denoted the pull electrode (see figure). In the off or open switch state, no voltage is applied, and the nanotube remains out of contact with the pull electrode. When a sufficiently large electric potential (switching potential) is applied between the pull electrode and either or both of the source and drain electrodes, the resulting electrostatic attraction bends and stretches the nanotube into contact with the pull electrode, thereby putting the switch into the "on" or "closed" state, in which substantial current (typically as much as hundreds of nanoamperes) is conducted. Devices of this type for use in initial experiments were fabricated on a thermally oxidized Si wafer, onto which Nb was sputter-deposited for use as the pull-electrode layer. Nb was chosen because its refractory nature would enable it to withstand the chemical and thermal conditions to be subsequently imposed for growing carbon nanotubes. A 200- nm-thick layer of SiO2 was formed on top of the Nb layer by plasma-enhanced chemical vapor deposition. In the device regions, the SiO2 layer was patterned to thin it to the 20-nm trench depth. The trenches were then patterned by electron- beam lithography and formed by reactive- ion etching of the pattern through the 20-nm-thick SiO2 to the Nb layer.

Ligand binding turns moth pheromone-binding protein into a pH sensor: effect on the Antheraea polyphemus PBP1 conformation.

PubMed

Katre, Uma V; Mazumder, Suman; Prusti, Rabi K; Mohanty, Smita

2009-11-13

In moths, pheromone-binding proteins (PBPs) are responsible for the transport of the hydrophobic pheromones to the membrane-bound receptors across the aqueous sensillar lymph. We report here that recombinant Antheraea polyphemus PBP1 (ApolPBP1) picks up hydrophobic molecule(s) endogenous to the Escherichia coli expression host that keeps the protein in the "open" (bound) conformation at high pH but switches to the "closed" (free) conformation at low pH. This finding has bearing on the solution structures of undelipidated lepidopteran moth PBPs determined thus far. Picking up a hydrophobic molecule from the host expression system could be a common feature for lipid-binding proteins. Thus, delipidation is critical for bacterially expressed lipid-binding proteins. We have shown for the first time that the delipidated ApolPBP1 exists primarily in the closed form at all pH levels. Thus, current views on the pH-induced conformational switch of PBPs hold true only for the ligand-bound open conformation of the protein. Binding of various ligands to delipidated ApolPBP1 studied by solution NMR revealed that the protein in the closed conformation switches to the open conformation only at or above pH 6.0 with a protein to ligand stoichiometry of approximately 1:1. Mutation of His(70) and His(95) to alanine drives the equilibrium toward the open conformation even at low pH for the ligand-bound protein by eliminating the histidine-dependent pH-induced conformational switch. Thus, the delipidated double mutant can bind ligand even at low pH in contrast to the wild type protein as revealed by fluorescence competitive displacement assay using 1-aminoanthracene and solution NMR.

Characterising switching behaviour in perceptual multi-stability.

PubMed

Denham, Susan; Bendixen, Alexandra; Mill, Robert; Tóth, Dénes; Wennekers, Thomas; Coath, Martin; Bőhm, Tamás; Szalardy, Orsolya; Winkler, István

2012-09-15

When people experience an unchanging sensory input for a long period of time, their perception tends to switch stochastically and unavoidably between alternative interpretations of the sensation; a phenomenon known as perceptual bi-stability or multi-stability. The huge variability in the experimental data obtained in such paradigms makes it difficult to distinguish typical patterns of behaviour, or to identify differences between switching patterns. Here we propose a new approach to characterising switching behaviour based upon the extraction of transition matrices from the data, which provide a compact representation that is well-understood mathematically. On the basis of this representation we can characterise patterns of perceptual switching, visualise and simulate typical switching patterns, and calculate the likelihood of observing a particular switching pattern. The proposed method can support comparisons between different observers, experimental conditions and even experiments. We demonstrate the insights offered by this approach using examples from our experiments investigating multi-stability in auditory streaming. However, the methodology is generic and thus widely applicable in studies of multi-stability in any domain. Copyright © 2012 Elsevier B.V. All rights reserved.

Maternal Immune Activation Delays Excitatory-to-Inhibitory Gamma-Aminobutyric Acid Switch in Offspring.

PubMed

Corradini, Irene; Focchi, Elisa; Rasile, Marco; Morini, Raffaella; Desiato, Genni; Tomasoni, Romana; Lizier, Michela; Ghirardini, Elsa; Fesce, Riccardo; Morone, Diego; Barajon, Isabella; Antonucci, Flavia; Pozzi, Davide; Matteoli, Michela

2018-04-15

The association between maternal infection and neurodevelopmental defects in progeny is well established, although the biological mechanisms and the pathogenic trajectories involved have not been defined. Pregnant dams were injected intraperitoneally at gestational day 9 with polyinosinic:polycytidylic acid. Neuronal development was assessed by means of electrophysiological, optical, and biochemical analyses. Prenatal exposure to polyinosinic:polycytidylic acid causes an imbalanced expression of the Na + -K + -2Cl - cotransporter 1 and the K + -Cl - cotransporter 2 (KCC2). This results in delayed gamma-aminobutyric acid switch and higher susceptibility to seizures, which endures up to adulthood. Chromatin immunoprecipitation experiments reveal increased binding of the repressor factor RE1-silencing transcription (also known as neuron-restrictive silencer factor) to position 509 of the KCC2 promoter that leads to downregulation of KCC2 transcription in prenatally exposed offspring. Interleukin-1 receptor type I knockout mice, which display braked immune response and no brain cytokine elevation upon maternal immune activation, do not display KCC2/Na + -K + -2Cl - cotransporter 1 imbalance when implanted in a wild-type dam and prenatally exposed. Notably, pretreatment of pregnant dams with magnesium sulfate is sufficient to prevent the early inflammatory state and the delay in excitatory-to-inhibitory switch associated to maternal immune activation. We provide evidence that maternal immune activation hits a key neurodevelopmental process, the excitatory-to-inhibitory gamma-aminobutyric acid switch; defects in this switch have been unequivocally linked to diseases such as autism spectrum disorder or epilepsy. These data open the avenue for a safe pharmacological treatment that may prevent the neurodevelopmental defects caused by prenatal immune activation in a specific pregnancy time window. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Adaptive synchronized switch damping on an inductor: a self-tuning switching law

NASA Astrophysics Data System (ADS)

Kelley, Christopher R.; Kauffman, Jeffrey L.

2017-03-01

Synchronized switch damping (SSD) techniques exploit low-power switching between passive circuits connected to piezoelectric material to reduce structural vibration. In the classical implementation of SSD, the piezoelectric material remains in an open circuit for the majority of the vibration cycle and switches briefly to a shunt circuit at every displacement extremum. Recent research indicates that this switch timing is only optimal for excitation exactly at resonance and points to more general optimal switch criteria based on the phase of the displacement and the system parameters. This work proposes a self-tuning approach that implements the more general optimal switch timing for synchronized switch damping on an inductor (SSDI) without needing any knowledge of the system parameters. The law involves a gradient-based search optimization that is robust to noise and uncertainties in the system. Testing of a physical implementation confirms this law successfully adapts to the frequency and parameters of the system. Overall, the adaptive SSDI controller provides better off-resonance steady-state vibration reduction than classical SSDI while matching performance at resonance.

RF Reference Switch for Spaceflight Radiometer Calibration

NASA Technical Reports Server (NTRS)

Knuble, Joseph

2013-01-01

The goal of this technology is to provide improved calibration and measurement sensitivity to the Soil Moisture Active Passive Mission (SMAP) radiometer. While RF switches have been used in the past to calibrate microwave radiometers, the switch used on SMAP employs several techniques uniquely tailored to the instrument requirements and passive remote-sensing in general to improve radiometer performance. Measurement error and sensitivity are improved by employing techniques to reduce thermal gradients within the device, reduce insertion loss during antenna observations, increase insertion loss temporal stability, and increase rejection of radar and RFI (radio-frequency interference) signals during calibration. The two legs of the single-pole double-throw reference switch employ three PIN diodes per leg in a parallel-shunt configuration to minimize insertion loss and increase stability while exceeding rejection requirements at 1,413 MHz. The high-speed packaged diodes are selected to minimize junction capacitance and resistance while ensuring the parallel devices have very similar I-V curves. Switch rejection is improved by adding high-impedance quarter-wave tapers before and after the diodes, along with replacing the ground via of one diode per leg with an open circuit stub. Errors due to thermal gradients in the switch are reduced by embedding the 50-ohm reference load within the switch, along with using a 0.25-in. (approximately equal to 0.6-cm) aluminum prebacked substrate. Previous spaceflight microwave radiometers did not embed the reference load and thermocouple directly within the calibration switch. In doing so, the SMAP switch reduces error caused by thermal gradients between the load and switch. Thermal issues are further reduced by moving the custom, highspeed regulated driver circuit to a physically separate PWB (printed wiring board). Regarding RF performance, previous spaceflight reference switches have not employed high-impedance tapers to improve rejection. The use of open-circuit stubs instead of a via to provide an improved RF short is unique to this design. The stubs are easily tunable to provide high rejection at specific frequencies while maintaining very low insertion loss in-band.

Speed and Accuracy of Accessing Information in Working Memory: An Individual Differences Investigation of Focus Switching

ERIC Educational Resources Information Center

Unsworth, Nash; Engle, Randall W.

2008-01-01

Three experiments examined the nature of individual differences in switching the focus of attention in working memory. Participants performed 3 versions of a continuous counting task that required successive updating and switching between counts. Across all 3 experiments, individual differences in working memory span and fluid intelligence were…

Central Cross-Talk in Task Switching : Evidence from Manipulating Input-Output Modality Compatibility

ERIC Educational Resources Information Center

Stephan, Denise Nadine; Koch, Iring

2010-01-01

Two experiments examined the role of compatibility of input and output (I-O) modality mappings in task switching. We define I-O modality compatibility in terms of similarity of stimulus modality and modality of response-related sensory consequences. Experiment 1 included switching between 2 compatible tasks (auditory-vocal vs. visual-manual) and…

Integral Battery Power Limiting Circuit for Intrinsically Safe Applications

NASA Technical Reports Server (NTRS)

Burns, Bradley M.; Blalock, Norman N.

2010-01-01

A circuit topology has been designed to guarantee the output of intrinsically safe power for the operation of electrical devices in a hazardous environment. This design uses a MOSFET (metal oxide semiconductor field-effect transistor) as a switch to connect and disconnect power to a load. A test current is provided through a separate path to the load for monitoring by a comparator against a preset threshold level. The circuit is configured so that the test current will detect a fault in the load and open the switch before the main current can respond. The main current passes through the switch and then an inductor. When a fault occurs in the load, the current through the inductor cannot change immediately, but the voltage drops immediately to safe levels. The comparator detects this drop and opens the switch before the current in the inductor has a chance to respond. This circuit protects both the current and voltage from exceeding safe levels. Typically, this type of protection is accomplished by a fuse or a circuit breaker, but in order for a fuse or a circuit breaker to blow or trip, the current must exceed the safe levels momentarily, which may be just enough time to ignite anything in a hazardous environment. To prevent this from happening, a fuse is typically current-limited by the addition of the resistor to keep the current within safe levels while the fuse reacts. The use of a resistor is acceptable for non-battery applications where the wasted energy and voltage drop across the resistor can be tolerated. The use of the switch and inductor minimizes the wasted energy. For example, a circuit runs from a 3.6-V battery that must be current-limited to 200 mA. If the circuit normally draws 10 mA, then an 18-ohm resistor would drop 180 mV during normal operation, while a typical switch (0.02 ohm) and inductor (0.97 ohm) would only drop 9.9 mV. From a power standpoint, the current-limiting resistor protection circuit wastes about 18 times more power than the switch and the inductor configuration. In the fault condition, both the resistor and the inductor react immediately. The resistor reacts by allowing more current to flow and dropping the voltage. Initially, the inductor reacts by dropping the voltage, and then by not allowing the current to change. When the comparator detects the drop in voltage, it opens the switch, thus preventing any further current flow. The inductor alone is not sufficient protection, because after the voltage drop has settled, the inductor would then allow the current to change, in this example, the current would be 3.7 A. In the fault condition, the resistor is flowing 200 mA until the fuse blows (anywhere from 1 ms to 100 s), while the switch and inductor combination is flowing about 2 A test current while monitoring for the fault to be corrected. Finally, as an additional safety feature, the circuit can be configured to hold the switch opened until both the load and source are disconnected.

Contagion of Cooperation in Static and Fluid Social Networks.

PubMed

Jordan, Jillian J; Rand, David G; Arbesman, Samuel; Fowler, James H; Christakis, Nicholas A

2013-01-01

Cooperation is essential for successful human societies. Thus, understanding how cooperative and selfish behaviors spread from person to person is a topic of theoretical and practical importance. Previous laboratory experiments provide clear evidence of social contagion in the domain of cooperation, both in fixed networks and in randomly shuffled networks, but leave open the possibility of asymmetries in the spread of cooperative and selfish behaviors. Additionally, many real human interaction structures are dynamic: we often have control over whom we interact with. Dynamic networks may differ importantly in the goals and strategic considerations they promote, and thus the question of how cooperative and selfish behaviors spread in dynamic networks remains open. Here, we address these questions with data from a social dilemma laboratory experiment. We measure the contagion of both cooperative and selfish behavior over time across three different network structures that vary in the extent to which they afford individuals control over their network ties. We find that in relatively fixed networks, both cooperative and selfish behaviors are contagious. In contrast, in more dynamic networks, selfish behavior is contagious, but cooperative behavior is not: subjects are fairly likely to switch to cooperation regardless of the behavior of their neighbors. We hypothesize that this insensitivity to the behavior of neighbors in dynamic networks is the result of subjects' desire to attract new cooperative partners: even if many of one's current neighbors are defectors, it may still make sense to switch to cooperation. We further hypothesize that selfishness remains contagious in dynamic networks because of the well-documented willingness of cooperators to retaliate against selfishness, even when doing so is costly. These results shed light on the contagion of cooperative behavior in fixed and fluid networks, and have implications for influence-based interventions aiming at increasing cooperative behavior.

Testing the limits of optimality: the effect of base rates in the Monty Hall dilemma.

PubMed

Herbranson, Walter T; Wang, Shanglun

2014-03-01

The Monty Hall dilemma is a probability puzzle in which a player tries to guess which of three doors conceals a desirable prize. After an initial selection, one of the nonchosen doors is opened, revealing that it is not a winner, and the player is given the choice of staying with the initial selection or switching to the other remaining door. Pigeons and humans were tested on two variants of the Monty Hall dilemma, in which one of the three doors had either a higher or a lower chance of containing the prize than did the other two options. The optimal strategy in both cases was to initially choose the lowest-probability door available and then switch away from it. Whereas pigeons learned to approximate the optimal strategy, humans failed to do so on both accounts: They did not show a preference for low-probability options, and they did not consistently switch. An analysis of performance over the course of training indicated that pigeons learned to perform a sequence of responses on each trial, and that sequence was one that yielded the highest possible rate of reinforcement. Humans, in contrast, continued to vary their responses throughout the experiment, possibly in search of a more complex strategy that would exceed the maximum possible win rate.

Molecular Dynamics of the Proline Switch and Its Role in Crk Signaling

PubMed Central

2015-01-01

The Crk adaptor proteins play a central role as a molecular timer for the formation of protein complexes including various growth and differentiation factors. The loss of regulation of Crk results in many kinds of cancers. A self-regulatory mechanism for Crk was recently proposed, which involves domain–domain rearrangement. It is initiated by a cis–trans isomerization of a specific proline residue (Pro238 in chicken Crk II) and can be accelerated by Cyclophilin A. To understand how the proline switch controls the autoinhibition at the molecular level, we performed large-scale molecular dynamics and metadynamics simulations in the context of short peptides and multidomain constructs of chicken Crk II. We found that the equilibrium and kinetic properties of the macrostates are regulated not only by the local environments of specified prolines but also by the global organization of multiple domains. We observe the two macrostates (cis closed/autoinhibited and trans open/uninhibited) consistent with NMR experiments and predict barriers. We also propose an intermediate state, the trans closed state, which interestingly was reported to be a prevalent state in human Crk II. The existence of this macrostate suggests that the rate of switching off the autoinhibition by Cyp A may be limited by the relaxation rate of this intermediate state. PMID:24702481

Molecular dynamics of the proline switch and its role in Crk signaling.

PubMed

Xia, Junchao; Levy, Ronald M

2014-05-01

The Crk adaptor proteins play a central role as a molecular timer for the formation of protein complexes including various growth and differentiation factors. The loss of regulation of Crk results in many kinds of cancers. A self-regulatory mechanism for Crk was recently proposed, which involves domain-domain rearrangement. It is initiated by a cis-trans isomerization of a specific proline residue (Pro238 in chicken Crk II) and can be accelerated by Cyclophilin A. To understand how the proline switch controls the autoinhibition at the molecular level, we performed large-scale molecular dynamics and metadynamics simulations in the context of short peptides and multidomain constructs of chicken Crk II. We found that the equilibrium and kinetic properties of the macrostates are regulated not only by the local environments of specified prolines but also by the global organization of multiple domains. We observe the two macrostates (cis closed/autoinhibited and trans open/uninhibited) consistent with NMR experiments and predict barriers. We also propose an intermediate state, the trans closed state, which interestingly was reported to be a prevalent state in human Crk II. The existence of this macrostate suggests that the rate of switching off the autoinhibition by Cyp A may be limited by the relaxation rate of this intermediate state.

Design of an improved RCD buffer circuit for full bridge circuit

NASA Astrophysics Data System (ADS)

Yang, Wenyan; Wei, Xueye; Du, Yongbo; Hu, Liang; Zhang, Liwei; Zhang, Ou

2017-05-01

In the full bridge inverter circuit, when the switch tube suddenly opened or closed, the inductor current changes rapidly. Due to the existence of parasitic inductance of the main circuit. Therefore, the surge voltage between drain and source of the switch tube can be generated, which will have an impact on the switch and the output voltage. In order to ab sorb the surge voltage. An improve RCD buffer circuit is proposed in the paper. The peak energy will be absorbed through the buffer capacitor of the circuit. The part energy feedback to the power supply, another part release through the resistor in the form of heat, and the circuit can absorb the voltage spikes. This paper analyzes the process of the improved RCD snubber circuit, According to the specific parameters of the main circuit, a reasonable formula for calculating the resistance capacitance is given. A simulation model will be modulated in Multisim, which compared the waveform of tube voltage and the output waveform of the circuit without snubber circuit with the improved RCD snubber circuit. By comparing and analyzing, it is proved that the improved buffer circuit can absorb surge voltage. Finally, experiments are demonstrated to validate that the correctness of the RC formula and the improved RCD snubber circuit.

Influence of affective valence on working memory processes.

PubMed

Gotoh, Fumiko

2008-02-01

Recent research has revealed widespread effects of emotion on cognitive function and memory. However, the influence of affective valence on working or short-term memory remains largely unexplored. In two experiments, the present study examined the predictions that negative words would capture attention, that attention would be difficult to disengage from such negative words, and that the cost of attention switching would increase the time required to update information in working memory. Participants switched between two concurrent working memory tasks: word recognition and a working memory digit updating task. Experiment 1 showed substantial switching cost for negative words, relative to neutral words. Experiment 2 replicated the first experiment, using a self-report measure of anxiety to examine if switching cost is a function of an anxiety-related attention bias. Results did not support this hypothesis. In addition, Experiment 2 revealed switch costs for positive words without the effect of the attention bias from anxiety. The present study demonstrates the effect of affective valence on a specific component of working memory. Moreover, findings suggest why affective valence effects on working memory have not been found in previous research.

Analysis of Cisco Open Network Environment (ONE) OpenFlow Controller Implementation

DTIC Science & Technology

2014-08-01

Software - Defined Networking ( SDN ), when fully realized, offer many improvements over the current rigid and...functionalities like handshake, connection setup, switch management, and security. 15. SUBJECT TERMS OpenFlow, software - defined networking , Cisco ONE, SDN ...innovating packet-forwarding technologies. Network device roles are strictly defined with little or no flexibility. In Software - Defined Networks ( SDNs ),

The effect of action video game experience on task-switching

PubMed Central

Green, C.Shawn; Sugarman, Michael A.; Medford, Katherine; Klobusicky, Elizabeth; Daphne Bavelier

2012-01-01

There is now a substantial body of work demonstrating that action video game experience results in enhancements in a wide variety of perceptual skills. More recently, several groups have also demonstrated improvements in abilities that are more cognitive in nature, in particular, the ability to efficiently switch between tasks. In a series of four experiments, we add to this body of work, demonstrating that the action video game player advantage is not exclusively due to an ability to map manual responses onto arbitrary buttons, but rather generalizes to vocal responses, is not restricted to tasks that are perceptual in nature (e.g. respond to a physical dimension of the stimulus such as its color), but generalizes to more cognitive tasks (e.g. is a number odd or even), and is present whether the switch requires a goal-switch or only a motor switch. Finally, a training study establishes that the relationship between the reduction in switch cost and action game playing is causal. PMID:22393270

Intentional preparation of auditory attention-switches: Explicit cueing and sequential switch-predictability.

PubMed

Seibold, Julia C; Nolden, Sophie; Oberem, Josefa; Fels, Janina; Koch, Iring

2018-06-01

In an auditory attention-switching paradigm, participants heard two simultaneously spoken number-words, each presented to one ear, and decided whether the target number was smaller or larger than 5 by pressing a left or right key. An instructional cue in each trial indicated which feature had to be used to identify the target number (e.g., female voice). Auditory attention-switch costs were found when this feature changed compared to when it repeated in two consecutive trials. Earlier studies employing this paradigm showed mixed results when they examined whether such cued auditory attention-switches can be prepared actively during the cue-stimulus interval. This study systematically assessed which preconditions are necessary for the advance preparation of auditory attention-switches. Three experiments were conducted that controlled for cue-repetition benefits, modality switches between cue and stimuli, as well as for predictability of the switch-sequence. Only in the third experiment, in which predictability for an attention-switch was maximal due to a pre-instructed switch-sequence and predictable stimulus onsets, active switch-specific preparation was found. These results suggest that the cognitive system can prepare auditory attention-switches, and this preparation seems to be triggered primarily by the memorised switching-sequence and valid expectations about the time of target onset.

Changes in weight and other metabolic indicators in persons with schizophrenia following a switch to aripiprazole.

PubMed

Ganguli, Rohan; Brar, Jaspreet S; Garbut, Ronald; Chang, Chung-Chou H; Basu, Ranita

2011-07-01

For patients who gain a troublesome amount of weight on antipsychotics, switching to a less obesogenic agent is an option. Aripiprazole appears to cause less weight gain than many other antipsychotics. We report on changes in weight, and other risk factors for heart disease, in thirty-three schizophrenia patients who agreed to switch from other antipsychotics to aripiprazole in an open, flexible-dose, eight-week trial. All patients were successfully switched. There were no significant changes in PANSS symptom scores or in CGI. Weight (Wt), waist circumference (WC), and low-density lipoprotein (LDL) decreased significantly in the group as a whole. In patients switched from olanzapine to aripiprazole, Wt, WC, LDL, fasting glucose, and triglycerides were significantly decreased as compared to baseline. Substantial decreases in several risk factors were also seen in patients switched from quetiapine, but these changes did not reach statistical significance.

Open Source and ROI: Open Source Has Made Significant Leaps in Recent Years. What Does It Have to Offer Education?

ERIC Educational Resources Information Center

Guhlin, Miguel

2007-01-01

A switch to free open source software can minimize cost and allow funding to be diverted to equipment and other programs. For instance, the OpenOffice suite is an alternative to expensive basic application programs offered by major vendors. Many such programs on the market offer features seldom used in education but for which educators must pay.…

General-Purpose Serial Interface For Remote Control

NASA Technical Reports Server (NTRS)

Busquets, Anthony M.; Gupton, Lawrence E.

1990-01-01

Computer controls remote television camera. General-purpose controller developed to serve as interface between host computer and pan/tilt/zoom/focus functions on series of automated video cameras. Interface port based on 8251 programmable communications-interface circuit configured for tristated outputs, and connects controller system to any host computer with RS-232 input/output (I/O) port. Accepts byte-coded data from host, compares them with prestored codes in read-only memory (ROM), and closes or opens appropriate switches. Six output ports control opening and closing of as many as 48 switches. Operator controls remote television camera by speaking commands, in system including general-purpose controller.

Light-weight DC to very high voltage DC converter

DOEpatents

Druce, R.L.; Kirbie, H.C.; Newton, M.A.

1998-06-30

A DC-DC converter capable of generating outputs of 100 KV without a transformer comprises a silicon opening switch (SOS) diode connected to allow a charging current from a capacitor to flow into an inductor. When a specified amount of charge has flowed through the SOS diode, it opens up abruptly; and the consequential collapsing field of the inductor causes a voltage and current reversal that is steered into a load capacitor by an output diode. A switch across the series combination of the capacitor, inductor, and SOS diode closes to periodically reset the SOS diode by inducing a forward-biased current. 1 fig.

Spectroscopic investigation of species separation in opening switch plasmas

NASA Astrophysics Data System (ADS)

Jackson, S. L.; Phipps, D. G.; Richardson, A. S.; Commisso, R. J.; Hinshelwood, D. D.; Murphy, D. P.; Schumer, J. W.; Weber, B. V.; Boyer, C. N.; Doron, R.; Biswas, S.; Maron, Y.

2015-11-01

Interactions between magnetic fields and current-carrying plasmas that lead to the separation of plasma species in multi-species plasmas are being studied in a plasma opening switch geometry. Several Marshall guns are used to inject single or multi-species plasmas between coaxial conductors connected to the output of the Naval Research Laboratory's Hawk pulsed-power generator. Following injection of the plasma, the generator is used at roughly half power to apply an electrical pulse with a peak current of 450 kA, a peak voltage of 400 kV, and a rise time of 1.2 μs. The resulting magnetic field interacts with the plasma through a combination of field penetration and magnetohydrodynamic (MHD) pushing that is not well understood but can lead to the separation of plasma species in multi-species plasmas. An ICCD-coupled spectrometer has been used in combination with magnetic probes, a ribbon-beam interferometer, and particle-in-cell (PIC) modeling to diagnose and understand conditions in the plasma from the time it is injected until the end of the conduction phase of the opening switch. This work supported by the Naval Research Laboratory Base Program and the Office of Naval Research.

Scaling Effect on Unipolar and Bipolar Resistive Switching of Metal Oxides

PubMed Central

Yanagida, Takeshi; Nagashima, Kazuki; Oka, Keisuke; Kanai, Masaki; Klamchuen, Annop; Park, Bae Ho; Kawai, Tomoji

2013-01-01

Electrically driven resistance change in metal oxides opens up an interdisciplinary research field for next-generation non-volatile memory. Resistive switching exhibits an electrical polarity dependent “bipolar-switching” and a polarity independent “unipolar-switching”, however tailoring the electrical polarity has been a challenging issue. Here we demonstrate a scaling effect on the emergence of the electrical polarity by examining the resistive switching behaviors of Pt/oxide/Pt junctions over 8 orders of magnitudes in the areas. We show that the emergence of two electrical polarities can be categorised as a diagram of an electric field and a cell area. This trend is qualitatively common for various oxides including NiOx, CoOx, and TiO2-x. We reveal the intrinsic difference between unipolar switching and bipolar switching on the area dependence, which causes a diversity of an electrical polarity for various resistive switching devices with different geometries. This will provide a foundation for tailoring resistive switching behaviors of metal oxides. PMID:23584551

Client-centred development of an infrared thermal access switch for a young adult with severe spastic quadriplegic cerebral palsy.

PubMed

Memarian, Negar; Venetsanopoulos, Anastasios N; Chau, Tom

2011-01-01

This study reports a client-centred development of a non-contact access switch based on an infrared thermal imaging of mouth opening-closing activity of an individual with severe spastic quadriplegic cerebral palsy. Over a 6-month period, the client participated in five test sessions to inform the development of an infrared thermal switch. The client completed eight stimulus-response trials (switch test) and eight word-matching trials (scan test) using the infrared thermal switch and provided subjective feedback throughout. For the switch test, the client achieved an average correct activation rate of 90% and average response time of 2.4 s. His mean correct activation rate on the scan test improved from 65 to 80% over the course of system development, with an average response time of 11.7 s. An infrared thermography switch tuned to a client's extant orofacial gestures is a practical non-invasive access solution and warrants further research in clients with severe physical disability.

The formation of the light-sensing compartment of cone photoreceptors coincides with a transcriptional switch

PubMed Central

Daum, Janine M; Keles, Özkan; Holwerda, Sjoerd JB; Kohler, Hubertus; Rijli, Filippo M

2017-01-01

High-resolution daylight vision is mediated by cone photoreceptors. The molecular program responsible for the formation of their light sensor, the outer segment, is not well understood. We correlated daily changes in ultrastructure and gene expression in postmitotic mouse cones, between birth and eye opening, using serial block-face electron microscopy (EM) and RNA sequencing. Outer segments appeared rapidly at postnatal day six and their appearance coincided with a switch in gene expression. The switch affected over 14% of all expressed genes. Genes that switched off were rich in transcription factors and neurogenic genes. Those that switched on contained genes relevant for cone function. Chromatin rearrangements in enhancer regions occurred before the switch was completed, but not after. We provide a resource comprised of correlated EM, RNAseq, and ATACseq data, showing that the growth of a key compartment of a postmitotic cell involves an extensive switch in gene expression and chromatin accessibility. PMID:29106373

Fabricating and using a micromachined magnetostatic relay or switch

NASA Technical Reports Server (NTRS)

Tai, Yu-Chong (Inventor); Wright, John A. (Inventor)

2001-01-01

A micromachined magnetostatic relay or switch includes a springing beam on which a magnetic actuation plate is formed. The springing beam also includes an electrically conductive contact. In the presence of a magnetic field, the magnetic material causes the springing beam to bend, moving the electrically conductive contact either toward or away from another contact, and thus creating either an electrical short-circuit or an electrical open-circuit. The switch is fabricated from silicon substrates and is particularly useful in forming a MEMs commutation and control circuit for a miniaturized DC motor.

Hybrid high direct current circuit interrupter

DOEpatents

Rockot, J.H.; Mikesell, H.E.; Jha, K.N.

1998-08-11

A device and a method are disclosed for interrupting very high direct currents (greater than 100,000 amperes) and simultaneously blocking high voltages (greater than 600 volts). The device utilizes a mechanical switch to carry very high currents continuously with low loss and a silicon controlled rectifier (SCR) to bypass the current around the mechanical switch while its contacts are separating. A commutation circuit, connected in parallel with the SCR, turns off the SCR by utilizing a resonant circuit to divert the SCR current after the switch opens. 7 figs.

HMSIW-based switchable units using super compact loaded shunt stubs and its applications on SIW/HMSIW switches

NASA Astrophysics Data System (ADS)

Chen, Haidong; Che, Wenquan; Zhang, Tianyu; Cao, Yue; Feng, Wenjie

2018-06-01

Half-mode substrate integrated waveguide (HMSIW) switchable unit, built by HMSIW section with loaded single or multi-microstrip shunt stub(s), was proposed in this work. Both shorted and opened stubs were studied, investigated and compared, bandwidth enhancement method for proposed switchable units was proposed and demonstrated. Based on these switchable units, narrowband and broadband HMSIW single-pole-single-through (SPST) switches, SIW SPST switch and SIW/HMSIW-based single-pole-double-through (SPDT) switch were designed, fabricated and measured. Good performances were observed experimentally for these proposed circuits, showing the advantages of proposed concept and an excellent candidate for switchable or reconfigurable SIW/HMSIW circuits or systems.

Inner surface flash-over of insulator of low-inductance high-voltage self-breakdown gas switch and its application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Hong-bo, E-mail: walkman67@163.com; Liu, Jin-liang

2014-04-15

In this paper, the inner surface flash-over of high-voltage self-breakdown switch, which is used as a main switch of pulse modulator, is analyzed in theory by employing the method of distributed element equivalent circuit. Moreover, the field distortion of the switch is simulated by using software. The results of theoretical analysis and simulation by software show that the inner surface flash-over usually starts at the junction points among the stainless steel, insulator, and insulation gas in the switch. A switch with improved structure is designed and fabricated according to the theoretical analysis and simulation results. Several methods to avoid innermore » surface flash-over are used to improve the structure of switch. In experiment, the inductance of the switch is no more than 100 nH, the working voltage of the switch is about 600 kV, and the output voltage and current of the accelerator is about 500 kV and 50 kA, respectively. And the zero-to-peak rise time of output voltage at matched load is less than 30 ns due to the small inductance of switch. The original switch was broken-down after dozens of experiments, and the improved switch has been worked more than 200 times stably.« less

A multi-functional high voltage experiment apparatus for vacuum surface flashover switch research.

PubMed

Zeng, Bo; Su, Jian-cang; Cheng, Jie; Wu, Xiao-long; Li, Rui; Zhao, Liang; Fang, Jin-peng; Wang, Li-min

2015-04-01

A multifunctional high voltage apparatus for experimental researches on surface flashover switch and high voltage insulation in vacuum has been developed. The apparatus is composed of five parts: pulse generating unit, axial field unit, radial field unit, and two switch units. Microsecond damped ringing pulse with peak-to-peak voltage 800 kV or unipolar pulse with maximum voltage 830 kV is generated, forming transient axial or radial electrical field. Different pulse waveforms and field distributions make up six experimental configurations in all. Based on this apparatus, preliminary experiments on vacuum surface flashover switch with different flashover dielectric materials have been conducted in the axial field unit, and nanosecond pulse is generated in the radial field unit which makes a pulse transmission line in the experiment. Basic work parameters of this kind of switch such as lifetime, breakdown voltage are obtained.

Qualitative Differences between Bilingual Language Control and Executive Control: Evidence from Task-Switching

PubMed Central

Calabria, Marco; Hernández, Mireia; Branzi, Francesca M.; Costa, Albert

2012-01-01

Previous research has shown that highly proficient bilinguals have comparable switch costs in both directions when they switch between languages (L1 and L2), the so-called “symmetrical switch cost” effect. Interestingly, the same symmetry is also present when they switch between L1 and a much weaker L3. These findings suggest that highly proficient bilinguals develop a language control system that seems to be insensitive to language proficiency. In the present study, we explore whether the pattern of symmetrical switch costs in language switching tasks generalizes to a non-linguistic switching task in the same group of highly proficient bilinguals. The end goal of this is to assess whether bilingual language control (bLC) can be considered as subsidiary to domain-general executive control (EC). We tested highly proficient Catalan–Spanish bilinguals both in a linguistic switching task and in a non-linguistic switching task. In the linguistic task, participants named pictures in L1 and L2 (Experiment 1) or L3 (Experiment 2) depending on a cue presented with the picture (a flag). In the non-linguistic task, the same participants had to switch between two card sorting rule-sets (color and shape). Overall, participants showed symmetrical switch costs in the linguistic switching task, but not in the non-linguistic switching task. In a further analysis, we observed that in the linguistic switching task the asymmetry of the switch costs changed across blocks, while in the non-linguistic switching task an asymmetrical switch cost was observed throughout the task. The observation of different patterns of switch costs in the linguistic and the non-linguistic switching tasks suggest that the bLC system is not completely subsidiary to the domain-general EC system. PMID:22275905

After stress comes relax(ation)

NASA Astrophysics Data System (ADS)

Isa, Lucio

2015-11-01

Viscoelastic materials take a finite time to relax and dissipate stress and this time scale is directly connected to the microstructure of the material itself. In their paper, Gomez-Solano and Bechinger (2015 New J. Phys. 17 103032) perform ‘miniaturized’ mechanical tests on a range of viscoelastic materials by dragging a micron-sized bead across them using optical tweezers. Upon switching off all the external forces, they watch the bead recoil to its original position and by tracking its motion they pinpoint the relaxation time of the material. These experiments open up a new range of possibilities to characterize stress relaxation at the microscale just by watching it.

The SRS railgun

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parker, J.V.

1989-01-01

A Segmented Rail Surface (SRS) structure is described that eliminates restrike arcs by progressively disconnecting segments of the rail surface after the plasma armature has passed. This technique has been demonstrated using the Los Alamos MIDI-2 railgun. Restrike was eliminated in a plasma armature acceleration experiment using metal-foil fuses as opening switches. A plasma velocity increase from 11 to 16 km/s was demonstrated using the SRS technique to eliminate the viscous drag losses associated with the restrike plasma. This technique appears to be a practical option for a laboratory launcher at present and for future multi-shot launchers if appropriate switchesmore » can be developed.« less

67. Building 102, view of electronic switching amplifier (in retracted ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

67. Building 102, view of electronic switching amplifier (in retracted or open position) with video monitor mounted at top to monitor performance and condition of system in oil bath. - Clear Air Force Station, Ballistic Missile Early Warning System Site II, One mile west of mile marker 293.5 on Parks Highway, 5 miles southwest of Anderson, Anderson, Denali Borough, AK

An Enhanced Three-Level Voltage Switching State Scheme for Direct Torque Controlled Open End Winding Induction Motor

NASA Astrophysics Data System (ADS)

Kunisetti, V. Praveen Kumar; Thippiripati, Vinay Kumar

2018-01-01

Open End Winding Induction Motors (OEWIM) are popular for electric vehicles, ship propulsion applications due to less DC link voltage. Electric vehicles, ship propulsions require ripple free torque. In this article, an enhanced three-level voltage switching state scheme for direct torque controlled OEWIM drive is implemented to reduce torque and flux ripples. The limitations of conventional Direct Torque Control (DTC) are: possible problems during low speeds and starting, it operates with variable switching frequency due to hysteresis controllers and produces higher torque and flux ripple. The proposed DTC scheme can abate the problems of conventional DTC with an enhanced voltage switching state scheme. The three-level inversion was obtained by operating inverters with equal DC-link voltages and it produces 18 voltage space vectors. These 18 vectors are divided into low and high frequencies of operation based on rotor speed. The hardware results prove the validity of proposed DTC scheme during steady-state and transients. From simulation and experimental results, proposed DTC scheme gives less torque and flux ripples on comparison to two-level DTC. The proposed DTC is implemented using dSPACE DS-1104 control board interface with MATLAB/SIMULINK-RTI model.

An Enhanced Three-Level Voltage Switching State Scheme for Direct Torque Controlled Open End Winding Induction Motor

NASA Astrophysics Data System (ADS)

Kunisetti, V. Praveen Kumar; Thippiripati, Vinay Kumar

2018-06-01

Open End Winding Induction Motors (OEWIM) are popular for electric vehicles, ship propulsion applications due to less DC link voltage. Electric vehicles, ship propulsions require ripple free torque. In this article, an enhanced three-level voltage switching state scheme for direct torque controlled OEWIM drive is implemented to reduce torque and flux ripples. The limitations of conventional Direct Torque Control (DTC) are: possible problems during low speeds and starting, it operates with variable switching frequency due to hysteresis controllers and produces higher torque and flux ripple. The proposed DTC scheme can abate the problems of conventional DTC with an enhanced voltage switching state scheme. The three-level inversion was obtained by operating inverters with equal DC-link voltages and it produces 18 voltage space vectors. These 18 vectors are divided into low and high frequencies of operation based on rotor speed. The hardware results prove the validity of proposed DTC scheme during steady-state and transients. From simulation and experimental results, proposed DTC scheme gives less torque and flux ripples on comparison to two-level DTC. The proposed DTC is implemented using dSPACE DS-1104 control board interface with MATLAB/SIMULINK-RTI model.

Syntactic Alignment and Shared Word Order in Code-Switched Sentence Production: Evidence from Bilingual Monologue and Dialogue

ERIC Educational Resources Information Center

Kootstra, Gerrit Jan; van Hell, Janet G.; Dijkstra, Ton

2010-01-01

In four experiments, we investigated the role of shared word order and alignment with a dialogue partner in the production of code-switched sentences. In Experiments 1 and 2, Dutch-English bilinguals code-switched in describing pictures while being cued with word orders that are either shared or not shared between Dutch and English. In Experiments…

A gating grid driver for time projection chambers

NASA Astrophysics Data System (ADS)

Tangwancharoen, S.; Lynch, W. G.; Barney, J.; Estee, J.; Shane, R.; Tsang, M. B.; Zhang, Y.; Isobe, T.; Kurata-Nishimura, M.; Murakami, T.; Xiao, Z. G.; Zhang, Y. F.; SπRIT Collaboration

2017-05-01

A simple but novel driver system has been developed to operate the wire gating grid of a Time Projection Chamber (TPC). This system connects the wires of the gating grid to its driver via low impedance transmission lines. When the gating grid is open, all wires have the same voltage allowing drift electrons, produced by the ionization of the detector gas molecules, to pass through to the anode wires. When the grid is closed, the wires have alternating higher and lower voltages causing the drift electrons to terminate at the more positive wires. Rapid opening of the gating grid with low pickup noise is achieved by quickly shorting the positive and negative wires to attain the average bias potential with N-type and P-type MOSFET switches. The circuit analysis and simulation software SPICE shows that the driver restores the gating grid voltage to 90% of the opening voltage in less than 0.20 μs, for small values of the termination resistors. When tested in the experimental environment of a time projection chamber larger termination resistors were chosen so that the driver opens the gating grid in 0.35 μs. In each case, opening time is basically characterized by the RC constant given by the resistance of the switches and terminating resistors and the capacitance of the gating grid and its transmission line. By adding a second pair of N-type and P-type MOSFET switches, the gating grid is closed by restoring 99% of the original charges to the wires within 3 μs.

Bilingual Control: Sequential Memory in Language Switching

ERIC Educational Resources Information Center

Declerck, Mathieu; Philipp, Andrea M.; Koch, Iring

2013-01-01

To investigate bilingual language control, prior language switching studies presented visual objects, which had to be named in different languages, typically indicated by a visual cue. The present study examined language switching of predictable responses by introducing a novel sequence-based language switching paradigm. In 4 experiments,…

Experimental Results from a Laser-Triggered, Gas-Insulated, Spark-Gap Switch

NASA Astrophysics Data System (ADS)

Camacho, J. F.; Ruden, E. L.; Domonkos, M. T.

2017-10-01

We are performing experiments on a laser-triggered spark-gap switch with the goal of studying the transition from photoionization to current conduction. The discharge of current through the switch is triggered by a focused 532-nm wavelength beam from a Q-switched Nd:YAG laser with a pulse duration of about 10 ns. The trigger pulse is delivered along the longitudinal axis of the switch, and the focal spot can be placed anywhere along the axis of the 5-mm, gas-insulated gap between the switch electrodes. The switch test bed is designed to support a variety of working gases (e.g., Ar, N2) over a range of pressures. Electrical and optical diagnostics are used to measure switch performance as a function of parameters such as charge voltage, trigger pulse energy, insulating gas pressure, and gas species. A Mach-Zehnder imaging interferometer system operating at 532 nm is being used to obtain interferograms of the discharge plasma in the switch. We are also developing a 1064-nm interferometry diagnostic in an attempt to measure plasma free electron and neutral gas density profiles simultaneously within the switch gap. Results from our most recent experiments will be presented.

47 CFR 69.111 - Tandem-switched transport and tandem charge.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., geographically averaged on a study-area-wide basis, that the incumbent local exchange carrier experiences based... exchange carrier experiences based on the prior year's annual use. Tandem-switched transport transmission..., geographically averaged on a study-area-wide basis, that the incumbent local exchange carrier experiences based...

An injection seeded single frequency Nd:YAG Q-switched laser with precisely controllable laser pulse firing time

NASA Astrophysics Data System (ADS)

Wu, Frank F.; Khizhnyak, Anatoliy; Markov, Vladimir

2010-02-01

We have realized a single frequency Q-switched Nd:YAG laser with precisely controllable lasing time and thus enabled synchronization of multi-laser systems. The use of injection seeding to the slave ring oscillator results in unidirectional Q-switched laser oscillation with suppression of bidirectional Q-switched oscillation that otherwise would be initiated from spontaneous emission if the seeding laser is not present. Under normal condition, the cavity is high in loss during the pumping period; then a Pockels cell opens the cavity to form the pulse build up, with a second Pockels cell to perform cavity dumping, generating the Q-switched pulse output with optimized characteristics. The two Pockels cells can be replaced by a single unit if an adjustable gated electrical pulse is applied to the Pockels cell in which the pulse front is used to open the cavity and the falling edge to dump the laser pulse. Proper selection of the pump parameters and Pockels-cell gating enables operation of the system in a mode in which the Q-switched pulse can be formed only under the seeding condition. The advantage of the realized regime is in stable laser operation with no need in adjustment of the seeded light wavelength and the mode of the cavity. It is found that the frequency of the Q-switched laser radiation matches well to the injected seeded laser mode. By using two-stage amplifiers, an output energy better than 300 mJ has been achieved in MOPA configuration without active control of the cavity length and with pulse width adjustability from several nanoseconds to 20 ns. The Q-switched oscillator operates not only at precisely controlled firing time but also can be tuned over wide range. This will enable multi-laser systems synchronization and frequency locking down each other if necessary.

Demonstration of reconfigurable joint orbital angular momentum mode and space switching

PubMed Central

Liu, Jun; Wang, Jian

2016-01-01

We propose and demonstrate space-selective switch functions employing orbital angular momentum (OAM) modes in the space domain for switching network. One is the switching among different OAM modes having different spatial phase structures, called OAM mode switching. The other is the switching among different space locations, called space switching. The switching operation mechanism relies on linear optics. Reconfigurable 4 × 4 OAM mode switching, space switching, and joint OAM mode and space switching fabric using a single spatial light modulator (SLM) are all demonstrated in the experiment. In addition, the presented OAM-incorporated space-selective switch might be further extended to N × N joint OAM mode and space switching with fast response, scalability, cascading ability and compability to facilitate robust switching applications. PMID:27869133

Demonstration of reconfigurable joint orbital angular momentum mode and space switching

NASA Astrophysics Data System (ADS)

Liu, Jun; Wang, Jian

2016-11-01

We propose and demonstrate space-selective switch functions employing orbital angular momentum (OAM) modes in the space domain for switching network. One is the switching among different OAM modes having different spatial phase structures, called OAM mode switching. The other is the switching among different space locations, called space switching. The switching operation mechanism relies on linear optics. Reconfigurable 4 × 4 OAM mode switching, space switching, and joint OAM mode and space switching fabric using a single spatial light modulator (SLM) are all demonstrated in the experiment. In addition, the presented OAM-incorporated space-selective switch might be further extended to N × N joint OAM mode and space switching with fast response, scalability, cascading ability and compability to facilitate robust switching applications.

Demonstration of reconfigurable joint orbital angular momentum mode and space switching.

PubMed

Liu, Jun; Wang, Jian

2016-11-21

We propose and demonstrate space-selective switch functions employing orbital angular momentum (OAM) modes in the space domain for switching network. One is the switching among different OAM modes having different spatial phase structures, called OAM mode switching. The other is the switching among different space locations, called space switching. The switching operation mechanism relies on linear optics. Reconfigurable 4 × 4 OAM mode switching, space switching, and joint OAM mode and space switching fabric using a single spatial light modulator (SLM) are all demonstrated in the experiment. In addition, the presented OAM-incorporated space-selective switch might be further extended to N × N joint OAM mode and space switching with fast response, scalability, cascading ability and compability to facilitate robust switching applications.

29 CFR 1926.950 - General requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... means of disconnecting from electric energy is not visibly open or visibly locked out, the provisions of...: (a) All switches and disconnectors through which electric energy may be supplied to the particular... clearly see that the means of disconnecting from electric energy are visibly open or visibly locked-out...

29 CFR 1926.950 - General requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... means of disconnecting from electric energy is not visibly open or visibly locked out, the provisions of...: (a) All switches and disconnectors through which electric energy may be supplied to the particular... clearly see that the means of disconnecting from electric energy are visibly open or visibly locked-out...

29 CFR 1926.950 - General requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... means of disconnecting from electric energy is not visibly open or visibly locked out, the provisions of...: (a) All switches and disconnectors through which electric energy may be supplied to the particular... clearly see that the means of disconnecting from electric energy are visibly open or visibly locked-out...

29 CFR 1926.950 - General requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

... means of disconnecting from electric energy is not visibly open or visibly locked out, the provisions of...: (a) All switches and disconnectors through which electric energy may be supplied to the particular... clearly see that the means of disconnecting from electric energy are visibly open or visibly locked-out...

Intentional attention switching in dichotic listening: exploring the efficiency of nonspatial and spatial selection.

PubMed

Lawo, Vera; Fels, Janina; Oberem, Josefa; Koch, Iring

2014-10-01

Using an auditory variant of task switching, we examined the ability to intentionally switch attention in a dichotic-listening task. In our study, participants responded selectively to one of two simultaneously presented auditory number words (spoken by a female and a male, one for each ear) by categorizing its numerical magnitude. The mapping of gender (female vs. male) and ear (left vs. right) was unpredictable. The to-be-attended feature for gender or ear, respectively, was indicated by a visual selection cue prior to auditory stimulus onset. In Experiment 1, explicitly cued switches of the relevant feature dimension (e.g., from gender to ear) and switches of the relevant feature within a dimension (e.g., from male to female) occurred in an unpredictable manner. We found large performance costs when the relevant feature switched, but switches of the relevant feature dimension incurred only small additional costs. The feature-switch costs were larger in ear-relevant than in gender-relevant trials. In Experiment 2, we replicated these findings using a simplified design (i.e., only within-dimension switches with blocked dimensions). In Experiment 3, we examined preparation effects by manipulating the cueing interval and found a preparation benefit only when ear was cued. Together, our data suggest that the large part of attentional switch costs arises from reconfiguration at the level of relevant auditory features (e.g., left vs. right) rather than feature dimensions (ear vs. gender). Additionally, our findings suggest that ear-based target selection benefits more from preparation time (i.e., time to direct attention to one ear) than gender-based target selection.

How do highly proficient bilinguals control their lexicalization process? Inhibitory and language-specific selection mechanisms are both functional.

PubMed

Costa, Albert; Santesteban, Mikel; Ivanova, Iva

2006-09-01

The authors report 4 experiments exploring the language-switching performance of highly proficient bilinguals in a picture-naming task. In Experiment 1, they tested the impact of language similarity and age of 2nd language acquisition on the language-switching performance of highly proficient bilinguals. Experiments 2, 3, and 4 assessed the performance of highly proficient bilinguals in language-switching contexts involving (a) the 2nd language (L2) and the L3 of the bilinguals, (b) the L3 and the L4, and (c) the L1 and a recently learned new language. Highly proficient bilinguals showed symmetrical switching costs regardless of the age at which the L2 was learned and of the similarities of the 2 languages and asymmetrical switching costs when 1 of the languages involved in the switching task was very weak (an L4 or a recently learned language). The theoretical implications of these results for the attentional mechanisms used by highly proficient bilinguals to control their lexicalization process are discussed. Copyright 2006 APA

Lifelong Bilingualism Maintains Neural Efficiency for Cognitive Control in Aging

PubMed Central

Gold, Brian T.; Kim, Chobok; Johnson, Nathan F.; Kryscio, Richard J.; Smith, Charles D.

2013-01-01

Recent behavioral data have shown that lifelong bilingualism can maintain youthful cognitive control abilities in aging. Here, we provide the first direct evidence of a neural basis for the bilingual cognitive control boost in aging. Two experiments were conducted, using a perceptual task switching paradigm, and including a total of 110 participants. In Experiment 1, older adult bilinguals showed better perceptual switching performance than their monolingual peers. In Experiment 2, younger and older adult monolinguals and bilinguals completed the same perceptual task switching experiment while fMRI was performed. Typical age-related performance reductions and fMRI activation increases were observed. However, like younger adults, bilingual older adults outperformed their monolingual peers while displaying decreased activation in left lateral frontal cortex and cingulate cortex. Critically, this attenuation of age-related over-recruitment associated with bilingualism was directly correlated with better task switching performance. In addition, the lower BOLD response in frontal regions accounted for 82% of the variance in the bilingual task switching reaction time advantage. These results suggest that lifelong bilingualism offsets age-related declines in the neural efficiency for cognitive control processes. PMID:23303919

An Alternative to the Stay/Switch Equation Assessed When Using a Changeover-Delay

PubMed Central

MacDonall, James S.

2015-01-01

An alternative to the generalized matching equation for understanding concurrent performances is the stay/switch model. For the stay/switch model, the important events are the contingencies and behaviors at each alternative. The current experiment compares the descriptions by two stay/switch equations, the original, empirically derived stay/switch equation and a more theoretically derived equation based on ratios of stay to switch responses matching ratios of stay to switch reinforcers. The present experiment compared descriptions by the original stay/switch equation when using and not using a changeover delay. It also compared descriptions by the more theoretical equation with and without a changeover delay. Finally, it compared descriptions of the concurrent performances by these two equations. Rats were trained in 15 conditions on identical concurrent random-interval schedules in each component of a multiple schedule. A COD operated in only one component. There were no consistent differences in the variance accounted for by each equation of concurrent performances whether or not a COD was used. The simpler equation found greater sensitivity to stay than to switch reinforcers. It also found a COD eliminated the influence of switch reinforcers. Because estimates of parameters were more meaningful when using the more theoretical stay/switch equation it is preferred. PMID:26299548

An alternative to the stay/switch equation assessed when using a changeover-delay.

PubMed

MacDonall, James S

2015-11-01

An alternative to the generalized matching equation for understanding concurrent performances is the stay/switch model. For the stay/switch model, the important events are the contingencies and behaviors at each alternative. The current experiment compares the descriptions by two stay/switch equations, the original, empirically derived stay/switch equation and a more theoretically derived equation based on ratios of stay to switch responses matching ratios of stay to switch reinforcers. The present experiment compared descriptions by the original stay/switch equation when using and not using a changeover delay. It also compared descriptions by the more theoretical equation with and without a changeover delay. Finally, it compared descriptions of the concurrent performances by these two equations. Rats were trained in 15 conditions on identical concurrent random-interval schedules in each component of a multiple schedule. A COD operated in only one component. There were no consistent differences in the variance accounted for by each equation of concurrent performances whether or not a COD was used. The simpler equation found greater sensitivity to stay than to switch reinforcers. It also found a COD eliminated the influence of switch reinforcers. Because estimates of parameters were more meaningful when using the more theoretical stay/switch equation it is preferred. Copyright © 2015 Elsevier B.V. All rights reserved.

Government and public health responses to e-cigarettes in New Zealand: vapers' perspectives.

PubMed

Fraser, Trish; Glover, Marewa; Truman, Penelope

2018-04-05

The New Zealand (NZ) government is to lift the ban on the sale of nicotine for use in electronic cigarettes (e-cigarettes). Using a naturalistic approach, we sought to understand how the current law was experienced by e-cigarette users (vapers). Twenty-nine vapers were interviewed by telephone, between May and September 2016, using a semi-structured interview schedule. Open-ended questions covered: initiating vaping, the experience of stopping smoking, technical problems encountered, reasons for vaping, acceptability of vaping, addiction to vaping and advice given to smokers about vaping. The audio recordings were transcribed and then independently coded using a general inductive thematic analysis. This paper presents the main theme which was that vapers employed a range of reactionary strategies to the ban on the sale of nicotine e-liquid in NZ. These included lobbying government, spreading the word, establishing vaper support groups, helping people stop smoking by switching to vaping and advocating for e-cigarettes to be incorporated into smoking cessation practice. Vapers' experience and observations form a popular or lay epidemiology--one that identified that e-cigarettes were helping people stop smoking and could thus deliver public health benefits. Public health researchers and workers, and government fears about vaping, and proposals to strengthen restrictions contributed to the growth of the vaper community who reacted by forming self-help groups and providing alternative cessation support to smokers. For a significant switch from smoking to vaping to occur, the health sector needs to have a change of attitude towards vaping that is positive, and the public needs evidence-based information on vaping. A first step could be for the health sector to collaborate with the vaping community to reorient current tobacco control and cessation practice to encourage smokers to switch to less harmful smoke-free alternatives to smoking.

Visualizing the Role of Molecular Orbitals in Charge Transport through Individual Diarylethene Isomers

PubMed Central

2016-01-01

Diarylethene molecules are prototype molecular switches with their two isomeric forms exhibiting strikingly different conductance, while maintaining similar length. We employed low-temperature scanning tunneling microscopy (STM) to resolve the energy and the spatial extend of the molecular orbitals of the open and closed isomers when lying on a Au(111) surface. We find an intriguing difference in the extension of the respective HOMOs and a peculiar energy splitting of the formerly degenerate LUMO of the open isomer. We then lift the two isomers with the tip of the STM and measure the current through the individual molecules. By a simple analytical model of the transport, we show that the previously determined orbital characteristics are essential ingredients for the complete understanding of the transport properties. We also succeeded in switching the suspended molecules by the current, while switching the ones which are in direct contact to the surface occurs nonlocally with the help of the electric field of the tip. PMID:27775886

Network speech systems technology program

NASA Astrophysics Data System (ADS)

Weinstein, C. J.

1981-09-01

This report documents work performed during FY 1981 on the DCA-sponsored Network Speech Systems Technology Program. The two areas of work reported are: (1) communication system studies in support of the evolving Defense Switched Network (DSN) and (2) design and implementation of satellite/terrestrial interfaces for the Experimental Integrated Switched Network (EISN). The system studies focus on the development and evaluation of economical and endurable network routing procedures. Satellite/terrestrial interface development includes circuit-switched and packet-switched connections to the experimental wideband satellite network. Efforts in planning and coordination of EISN experiments are reported in detail in a separate EISN Experiment Plan.

Picosecond High Pressure Gas Switch Experiment

DTIC Science & Technology

1993-06-01

the calculated pulse waveform for a much higher voltage and pressure switch . Also, a discussion of the modifications made on an existing pulse...s 80 8 ~ 60 J 40 .. : ~--~: __ ~’----~-~ 0.1 10 100 1000 Frequency Figure 7. Output switch recovery. Conclusion The high- pressure switch has...effective in matching experimental results, and should thus be useful in the design of high-voltage and pressure switch configurations

Reversible switch between the nanoporous and the nonporous state of amphiphilic block copolymer films regulated by selective swelling.

PubMed

Yan, Nina; Wang, Yong

2015-09-21

Switchable nanoporous films, which can repeatedly alternate their porosities, are of great interest in a diversity of fields. Currently these intelligent materials are mostly based on polyelectrolytes and their porosities can change only in relatively narrow ranges, typically under wet conditions, severely limiting their applications. Here we develop a new system, which is capable of reversibly switching between a highly porous state and a nonporous state dozens of times regulated simply by exposure to selective solvents. In this system nanopores are created or reversibly eliminated in films of a block copolymer, polystyrene-block-poly(2-vinyl pyridine) (PS-b-P2VP), by exposing the films to P2VP-selective or PS-selective solvents, respectively. The mechanism of the switch is based on the selective swelling of the constituent blocks in corresponding solvents, which is a nondestructive and easily controllable process enabling the repeatable and ample switch between the open and the closed state. Systematic microscopic and ellipsometric characterization methods are performed to elucidate the pore-closing course induced by nonsolvents and the cycling between the pore-open and the pore-closed state up to 20 times. The affinity of the solvent for PS blocks is found to play a dominating role in determining the pore-closing process and the porosities of the pore-open films increase with the cycling numbers as a result of loose packing conditions of the polymer chains. We finally demonstrate the potential applications of these films as intelligent antireflection coatings and drug carriers.

Physics Notes.

ERIC Educational Resources Information Center

School Science Review, 1983

1983-01-01

Presented are physics experiments, laboratory procedures, demonstrations, and classroom materials/activities. Experiments include: speed of sound in carbon dioxide; inverse square law; superluminal velocities; and others. Equipment includes: current switch; electronic switch; and pinhole camera. Discussion of mechanics of walking is also included.…

The Role of Response Repetition in Task Switching

ERIC Educational Resources Information Center

Cooper, Stephen; Mari-Beffa, Paloma

2008-01-01

When switching between tasks, participants are sometimes required to use different response sets for each task. Thus, task switch and response set switch are confounded. In 5 experiments, the authors examined transitions of response within a linear 4-finger arrangement. A random baseline condition was compared with the cuing of specific response…

The Stay/Switch Model of Concurrent Choice

ERIC Educational Resources Information Center

MacDonall, James S.

2009-01-01

This experiment compared descriptions of concurrent choice by the stay/switch model, which says choice is a function of the reinforcers obtained for staying at and for switching from each alternative, and the generalized matching law, which says choice is a function of the total reinforcers obtained at each alternative. For the stay/switch model…

Development, Integration and Testing of Automated Triggering Circuit for Hybrid DC Circuit Breaker

NASA Astrophysics Data System (ADS)

Kanabar, Deven; Roy, Swati; Dodiya, Chiragkumar; Pradhan, Subrata

2017-04-01

A novel concept of Hybrid DC circuit breaker having combination of mechanical switch and static switch provides arc-less current commutation into the dump resistor during quench in superconducting magnet operation. The triggering of mechanical and static switches in Hybrid DC breaker can be automatized which can effectively reduce the overall current commutation time of hybrid DC circuit breaker and make the operation independent of opening time of mechanical switch. With this view, a dedicated control circuit (auto-triggering circuit) has been developed which can decide the timing and pulse duration for mechanical switch as well as static switch from the operating parameters. This circuit has been tested with dummy parameters and thereafter integrated with the actual test set up of hybrid DC circuit breaker. This paper deals with the conceptual design of the auto-triggering circuit, its control logic and operation. The test results of Hybrid DC circuit breaker using this circuit have also been discussed.

Multiple switch actuator

DOEpatents

Beyer, Edward T.

1976-01-06

The present invention relates to switches and switch actuating devices to be operated for purposes of arming a bomb or other missile as it is dropped or released from an aircraft. The particular bomb or missile in which this invention is applied is one in which there is a plurality of circuits which are to be armed by the closing of switches upon dropping or releasing of the bomb. The operation of the switches to closed position is normally accomplished by means of a pull-out wire; that is, a wire which is withdrawn from the bomb or missile at the time of release of the bomb, one end of the wire being attached to the aircraft. The conditions to be met are that the arming switches must be positively and surely maintained in open position until the bomb is released and the arming action is effected. The action of the pull-out wire in achieving the arming action must be sure and positive with minimum danger of malfunctioning, jamming or binding.

Switching from an oral dopamine receptor agonist to rotigotine transdermal patch: a review of clinical data with a focus on patient perspective.

PubMed

Chung, Sun Ju; Asgharnejad, Mahnaz; Bauer, Lars; Benitez, Arturo; Boroojerdi, Babak; Heidbrede, Tanja; Little, Allison; Kim, Han Joon

2017-07-01

Dopamine receptor agonists (DAs) are commonly used to treat Parkinson's disease (PD) and restless legs syndrome (RLS). In certain situations, switching from oral DAs to rotigotine transdermal patch may be beneficial for the patient (e.g., optimal symptom control/side effects/perioperative management, preference for once-daily/non-oral administration, RLS augmentation treatment). Areas covered: This narrative review summarizes available data on DA dose equivalency, dose conversions, switching schedules, safety, tolerability, efficacy and patient treatment preferences of switching from oral DAs to rotigotine (and vice versa) in patients with PD/RLS. The studies were identified in a PubMed search (up to 8 November 2016) using terms ('dopamine receptor agonist' OR 'rotigotine') AND 'switch'. Expert commentary: Randomized controlled studies often do not address the challenges clinicians face in practice, e.g., switching medications within the same class when dosing is not a one-to-one ratio. The authors describe three open-label studies in PD where oral DAs were successfully switched to rotigotine, and review three studies in RLS where oral DAs/levodopa were switched to rotigotine. Finally, the authors provide a suggested tool for switching from oral DAs to rotigotine, which includes dose conversion factors and switching schedules. The authors' view is that low-dose oral DAs (equivalent to ≤8 mg/24 h rotigotine) may be switched overnight.

A 0.2 V Micro-Electromechanical Switch Enabled by a Phase Transition.

PubMed

Dong, Kaichen; Choe, Hwan Sung; Wang, Xi; Liu, Huili; Saha, Bivas; Ko, Changhyun; Deng, Yang; Tom, Kyle B; Lou, Shuai; Wang, Letian; Grigoropoulos, Costas P; You, Zheng; Yao, Jie; Wu, Junqiao

2018-04-01

Micro-electromechanical (MEM) switches, with advantages such as quasi-zero leakage current, emerge as attractive candidates for overcoming the physical limits of complementary metal-oxide semiconductor (CMOS) devices. To practically integrate MEM switches into CMOS circuits, two major challenges must be addressed: sub 1 V operating voltage to match the voltage levels in current circuit systems and being able to deliver at least millions of operating cycles. However, existing sub 1 V mechanical switches are mostly subject to significant body bias and/or limited lifetimes, thus failing to meet both limitations simultaneously. Here 0.2 V MEM switching devices with ≳10 6 safe operating cycles in ambient air are reported, which achieve the lowest operating voltage in mechanical switches without body bias reported to date. The ultralow operating voltage is mainly enabled by the abrupt phase transition of nanolayered vanadium dioxide (VO 2 ) slightly above room temperature. The phase-transition MEM switches open possibilities for sub 1 V hybrid integrated devices/circuits/systems, as well as ultralow power consumption sensors for Internet of Things applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Efficacy and tolerability of brinzolamide/brimonidine suspension and prostaglandin analogs in patients previously treated with dorzolamide/timolol solution and prostaglandin analogs.

PubMed

Lo, Jonathan S; Pang, Pierre M; Lo, Samuel C

2016-01-01

Fixed combination glaucoma medication is increasingly used in glaucoma treatment. There is a lack of comparative study in the literature of non-beta blocker combination agents used adjunctively with a glaucoma agent in a different class. The objective of this study is to evaluate the effect of intraocular pressure (IOP) control and tolerability of non-beta blocker combination suspension with prostaglandin analogs (PGA) in patients with open angle glaucoma who were previously treated with beta blocker combination solution with PGA. Open-label retrospective review of patient records. This study looked at patients with open angle glaucoma taking dorzolamide/timolol solution with PGA that were switched to brinzolamide/brimonidine combination suspension with PGA. This study reviewed the charts of all patients who were at least 21 years old with a clinical diagnosis of open-angle glaucoma or ocular hypertension in at least one eye. Patients needed to have been treated with concomitant use of PGA and dorzolamide/timolol solution for at least one month. Patients using dorzolamide/timolol solution plus PGA with medication related ocular irritation were switched to brinzolamide/brimonidine suspension with the same PGA. Best-corrected visual acuity, ocular hyperemia grading, slit lamp biomicroscopy and Goldmann applanation tonometry measurements, and patient medication preferences were assessed at baseline, 1 month and 3 months. Forty eyes with open angle glaucoma. The mean age of the patients was 68 and 60% were females. The IOP before the switch was 17.2 and 16.5 (P=0.70) following the switch at 3 months. We found a decreasing trend of ocular hyperemia (P=0.064) and strong preference (P=0.011) for non-beta blocker combination suspension but no difference of visual acuity and slit lamp findings. Brinzolamide/brimonidine combination suspension when used adjunctively with PGA is equally effective. Patients in this study reported greatly reduced ocular redness and shorter duration of stinging with non-beta blocker combination suspension. Their preference of it over dorzolamide/timolol combination solution makes it a viable treatment option, particularly for the aging glaucoma patient with comorbidities that restrict the beta blocker use.

A Tesla-pulse forming line-plasma opening switch pulsed power generator.

PubMed

Novac, B M; Kumar, R; Smith, I R

2010-10-01

A pulsed power generator based on a high-voltage Tesla transformer which charges a 3.85 Ω/55 ns water-filled pulse forming line to 300 kV has been developed at Loughborough University as a training tool for pulsed power students. The generator uses all forms of insulation specific to pulsed power technology, liquid (oil and water), gas (SF(6)), and magnetic insulation in vacuum, and a number of fast voltage and current sensors are implemented for diagnostic purposes. A miniature (centimeter-size) plasma opening switch has recently been coupled to the output of the pulse forming line, with the overall system comprising the first phase of a program aimed at the development of a novel repetitive, table-top generator capable of producing 15 GW pulses for high power microwave loads. Technical details of all the generator components and the main experimental results obtained during the program and demonstrations of their performance are presented in the paper, together with a description of the various diagnostic tools involved. In particular, it is shown that the miniature plasma opening switch is capable of reducing the rise time of the input current while significantly increasing the load power. Future plans are outlined in the conclusions.

Ring opening polymerisation of lactide with uranium(iv) and cerium(iv) phosphinoaryloxide complexes.

PubMed

Sinclair, Fern; Hlina, Johann A; Wells, Jordann A L; Shaver, Michael P; Arnold, Polly L

2017-08-22

The C 3 -symmetric uranium(iv) and cerium(iv) complexes Me 3 SiOM(OAr P ) 3 , M = U (1), Ce (2), OAr P = OC 6 H 2 -6- t Bu-4-Me-2-PPh 2 , have been prepared and the difference between these 4f and 5f congeners as initiators for the ring opening polymerisation (ROP) of l-lactide is compared. The poorly controlled reactivity of the homoleptic analogue U(OAr P ) 4 (3) demonstrates the importance of the M-OSiMe 3 initiating group. The incorporation of a nickel atom in 1 to form the U-Ni heterobimetallic complex Me 3 SiOU(OAr P ) 3 Ni (4) may be the first example of the use of the inverse trans influence to switch the reactivity of a complex. This would imply the formation of the U-Ni bond strengthens the U-OSiMe 3 bond to such an extent that the ROP catalysis is switched off. Changing the conditions to immortal polymerisation dramatically increases polymerisation rates, and switches the order, with the Ce complex now faster than the U analogue, suggesting ligand protonolysis to afford a more open coordination sphere. For the ROP of rac-lactide, uranium complex 1 promotes heterotacticity at the highest levels of stereocontrol yet reported for an actinide complex.

Anticipatory control through associative learning of subliminal relations: invisible may be better than visible.

PubMed

Farooqui, Ausaf A; Manly, Tom

2015-03-01

We showed that anticipatory cognitive control could be unconsciously instantiated through subliminal cues that predicted enhanced future control needs. In task-switching experiments, one of three subliminal cues preceded each trial. Participants had no conscious experience or knowledge of these cues, but their performance was significantly improved on switch trials after cues that predicted task switches (but not particular tasks). This utilization of subliminal information was flexible and adapted to a change in cues predicting task switches and occurred only when switch trials were difficult and effortful. When cues were consciously visible, participants were unable to discern their relevance and could not use them to enhance switch performance. Our results show that unconscious cognition can implicitly use subliminal information in a goal-directed manner for anticipatory control, and they also suggest that subliminal representations may be more conducive to certain forms of associative learning. © The Author(s) 2015.

Asynchronous Transfer Mode (ATM) Switch Technology and Vendor Survey

NASA Technical Reports Server (NTRS)

Berry, Noemi

1995-01-01

Asynchronous Transfer Mode (ATM) switch and software features are described and compared in order to make switch comparisons meaningful. An ATM switch's performance cannot be measured solely based on its claimed switching capacity; traffic management and congestion control are emerging as the determining factors in an ATM network's ultimate throughput. Non-switch ATM products and experiences with actual installations of ATM networks are described. A compilation of select vendor offerings as of October 1994 is provided in chart form.

Cueing cognitive flexibility: Item-specific learning of switch readiness.

PubMed

Chiu, Yu-Chin; Egner, Tobias

2017-12-01

The rich behavioral repertoire of the human species derives from our ability to flexibly reconfigure processing strategies (task sets) in response to changing requirements. This updating of task sets is effortful, as reflected by longer response times when switching a task than repeating it (switch costs). However, some recent data suggest that switch costs can be reduced by cueing switch readiness bottom-up, by associating particular stimuli with frequent switch requirements. This type of "stimulus-control (S-C) learning" would be highly adaptive, as it combines the speed of automatic (bottom-up) processing with the flexibility and generalizability of controlled (top-down) processing. However, it is unclear whether S-C learning of switch readiness is truly possible, and what the underlying mechanisms are. Here we address these questions by pairing specific stimuli with a need to update task-sets either frequently or rarely. In all 3 experiments, we observe robust item-specific switch probability (ISSP) effects as revealed by smaller switch costs for frequent switch items than for rare switch items. By including a neutral condition, we also show that the ISSP effect is primarily driven by S-C learning reducing switch costs in frequent switch items. Furthermore, by employing 3 tasks in Experiment 3, we establish that the ISSP effect reflects an enhancement of general switch readiness, rather than of the readiness to switch to a specific alternate task. These results firmly establish that switch readiness is malleable by item-specific S-C learning processes, documenting that a generalizable state of cognitive flexibility can be primed by a bottom-up stimulus. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Non-oxidized porous silicon-based power AC switch peripheries.

PubMed

Menard, Samuel; Fèvre, Angélique; Valente, Damien; Billoué, Jérôme; Gautier, Gaël

2012-10-11

We present in this paper a novel application of porous silicon (PS) for low-power alternating current (AC) switches such as triode alternating current devices (TRIACs) frequently used to control small appliances (fridge, vacuum cleaner, washing machine, coffee makers, etc.). More precisely, it seems possible to benefit from the PS electrical insulation properties to ensure the OFF state of the device. Based on the technological aspects of the most commonly used AC switch peripheries physically responsible of the TRIAC blocking performances (leakage current and breakdown voltage), we suggest to isolate upper and lower junctions through the addition of a PS layer anodically etched from existing AC switch diffusion profiles. Then, we comment the voltage capability of practical samples emanating from the proposed architecture. Thanks to the characterization results of simple Al-PS-Si(P) structures, the experimental observations are interpreted, thus opening new outlooks in the field of AC switch peripheries.

Self-testing security sensor for monitoring closure of vault doors and the like

DOEpatents

Cawthorne, Duane C.

1997-05-27

A self-testing device is provided for a monitoring system for monitoring whether a closure member such as a door or window is closed. The monitoring system includes a switch unit mounted on the frame of the closure member being monitored and including magnetically biased switches connected in one or more electrical monitoring circuits, and a door magnet unit mounted on the closure member being monitored. The door magnet includes one or more permanent magnets that produce a magnetic field which, when the closure member is closed, cause said switches to assume a first state. When the closure member is opened, the switches switch to a second, alarm state. The self-testing device is electrically controllable from a remote location and produces a canceling or diverting magnetic field which simulates the effect of movement of the closure member from the closed position thereof without any actual movement of the member.

Self-testing security sensor for monitoring closure of vault doors and the like

DOEpatents

Cawthorne, D.C.

1997-05-27

A self-testing device is provided for a monitoring system for monitoring whether a closure member such as a door or window is closed. The monitoring system includes a switch unit mounted on the frame of the closure member being monitored and including magnetically biased switches connected in one or more electrical monitoring circuits, and a door magnet unit mounted on the closure member being monitored. The door magnet includes one or more permanent magnets that produce a magnetic field which, when the closure member is closed, cause said switches to assume a first state. When the closure member is opened, the switches switch to a second, alarm state. The self-testing device is electrically controllable from a remote location and produces a canceling or diverting magnetic field which simulates the effect of movement of the closure member from the closed position thereof without any actual movement of the member. 5 figs.

45° sign switching of effective exchange bias due to competing anisotropies in fully epitaxial Co3FeN/MnN bilayers.

PubMed

Hajiri, T; Yoshida, T; Filianina, M; Jaiswal, S; Borie, B; Asano, H; Zabel, H; Kläui, M

2017-12-05

We report an unusual angular-dependent exchange bias effect in ferromagnet/antiferromagnet bilayers, where both ferromagnet and antiferromagnet are epitaxially grown. Numerical model calculations predict an approximately 45° period for the sign switching of the exchange-bias field, depending on the ratio between magnetocrystalline anisotropy and exchange-coupling constant. The switching of the sign is indicative of a competition between a fourfold magnetocrystalline anisotropy of the ferromagnet and a unidirectional anisotropy field of the exchange coupling. This predicted unusual angular-dependent exchange bias and its magnetization switching process are confirmed by measurements on fully epitaxial Co 3 FeN/MnN bilayers by longitudinal and transverse magneto-optic Kerr effect magnetometry. These results provide a deeper understanding of the exchange coupling phenomena in fully epitaxial bilayers with tailored materials and open up a complex switching energy landscape engineering by anisotropies.

45° sign switching of effective exchange bias due to competing anisotropies in fully epitaxial Co3FeN/MnN bilayers

NASA Astrophysics Data System (ADS)

Hajiri, T.; Yoshida, T.; Filianina, M.; Jaiswal, S.; Borie, B.; Asano, H.; Zabel, H.; Kläui, M.

2018-01-01

We report an unusual angular-dependent exchange bias effect in ferromagnet/antiferromagnet bilayers, where both ferromagnet and antiferromagnet are epitaxially grown. Numerical model calculations predict an approximately 45° period for the sign switching of the exchange-bias field, depending on the ratio between magnetocrystalline anisotropy and exchange-coupling constant. The switching of the sign is indicative of a competition between a fourfold magnetocrystalline anisotropy of the ferromagnet and a unidirectional anisotropy field of the exchange coupling. This predicted unusual angular-dependent exchange bias and its magnetization switching process are confirmed by measurements on fully epitaxial Co3FeN/MnN bilayers by longitudinal and transverse magneto-optic Kerr effect magnetometry. These results provide a deeper understanding of the exchange coupling phenomena in fully epitaxial bilayers with tailored materials and open up a complex switching energy landscape engineering by anisotropies.

The effect of the market opening on trends in smoking rates in Taiwan.

PubMed

Hsu, Chih Cheng; Levy, David Theodore; Wen, Chi Pang; Cheng, Ting Yuan; Tsai, Shan Pou; Chen, Ted; Eriksen, Michael P; Shu, Chen Chun

2005-09-28

To examine smoking rates before and after the opening of the market to foreign imports. Consumer surveys of Monopoly Bureau, National Health Interview Survey and official tobacco consumption, production and import data were used to calculate smoking rates, cigarette consumption, and the market share of imports. Age-adjusted smoking rates were used to compare trends before and after the market opening. The market share of the imports reached half in 2001 from 2% before opening. Compared to projected rates, smoking rates in 2001 for all and younger males, and all and younger females were increased by 12, 6, 202, and 249%, respectively, over and above the projected trends. The ratio of smoking rates between younger and older adults became larger, from 0.62 to 0.74 in males and from 0.32 to 0.98 in females. Per capita consumption increased after the market opening, particularly when large increases in smuggled cigarettes were considered. The finding that the market opening triggered an increase in smoking rates is contrary to the assertion by U.S. cigarette producers that importation would only make smokers switch brands. Younger adults and females were more affected, reflecting their higher sensitivity to the appeal from foreign cigarettes. Because of the marketing strategy of imports, more young people smoked, at an earlier age. Experience from Taiwan revealed that after the initial increase in smoking rates, the opening had galvanized the anti-smoking sentiments, legitimized and strengthened tobacco control policies and tempered the severity of the adverse impact.

Recent Advance on Mesoporous Silica Nanoparticles-Based Controlled Release System: Intelligent Switches Open up New Horizon

PubMed Central

Sun, Ruijuan; Wang, Wenqian; Wen, Yongqiang; Zhang, Xueji

2015-01-01

Mesoporous silica nanoparticle (MSN)-based intelligent transport systems have attracted many researchers’ attention due to the characteristics of uniform pore and particle size distribution, good biocompatibility, high surface area, and versatile functionalization, which have led to their widespread application in diverse areas. In the past two decades, many kinds of smart controlled release systems were prepared with the development of brilliant nano-switches. This article reviews and discusses the advantages of MSN-based controlled release systems. Meanwhile, the switching mechanisms based on different types of stimulus response are systematically analyzed and summarized. Additionally, the application fields of these devices are further discussed. Obviously, the recent evolution of smart nano-switches promoted the upgrading of the controlled release system from the simple “separated” switch to the reversible, multifunctional, complicated logical switches and selective switches. Especially the free-blockage switches, which are based on hydrophobic/hydrophilic conversion, have been proposed and designed in the last two years. The prospects and directions of this research field are also briefly addressed, which could be better used to promote the further development of this field to meet the needs of mankind. PMID:28347110

Redefining the Speed Limit of Phase Change Memory Revealed by Time-resolved Steep Threshold-Switching Dynamics of AgInSbTe Devices

NASA Astrophysics Data System (ADS)

Shukla, Krishna Dayal; Saxena, Nishant; Durai, Suresh; Manivannan, Anbarasu

2016-11-01

Although phase-change memory (PCM) offers promising features for a ‘universal memory’ owing to high-speed and non-volatility, achieving fast electrical switching remains a key challenge. In this work, a correlation between the rate of applied voltage and the dynamics of threshold-switching is investigated at picosecond-timescale. A distinct characteristic feature of enabling a rapid threshold-switching at a critical voltage known as the threshold voltage as validated by an instantaneous response of steep current rise from an amorphous off to on state is achieved within 250 picoseconds and this is followed by a slower current rise leading to crystallization. Also, we demonstrate that the extraordinary nature of threshold-switching dynamics in AgInSbTe cells is independent to the rate of applied voltage unlike other chalcogenide-based phase change materials exhibiting the voltage dependent transient switching characteristics. Furthermore, numerical solutions of time-dependent conduction process validate the experimental results, which reveal the electronic nature of threshold-switching. These findings of steep threshold-switching of ‘sub-50 ps delay time’, opens up a new way for achieving high-speed non-volatile memory for mainstream computing.

BioWord: A sequence manipulation suite for Microsoft Word

PubMed Central

2012-01-01

Background The ability to manipulate, edit and process DNA and protein sequences has rapidly become a necessary skill for practicing biologists across a wide swath of disciplines. In spite of this, most everyday sequence manipulation tools are distributed across several programs and web servers, sometimes requiring installation and typically involving frequent switching between applications. To address this problem, here we have developed BioWord, a macro-enabled self-installing template for Microsoft Word documents that integrates an extensive suite of DNA and protein sequence manipulation tools. Results BioWord is distributed as a single macro-enabled template that self-installs with a single click. After installation, BioWord will open as a tab in the Office ribbon. Biologists can then easily manipulate DNA and protein sequences using a familiar interface and minimize the need to switch between applications. Beyond simple sequence manipulation, BioWord integrates functionality ranging from dyad search and consensus logos to motif discovery and pair-wise alignment. Written in Visual Basic for Applications (VBA) as an open source, object-oriented project, BioWord allows users with varying programming experience to expand and customize the program to better meet their own needs. Conclusions BioWord integrates a powerful set of tools for biological sequence manipulation within a handy, user-friendly tab in a widely used word processing software package. The use of a simple scripting language and an object-oriented scheme facilitates customization by users and provides a very accessible educational platform for introducing students to basic bioinformatics algorithms. PMID:22676326

BioWord: a sequence manipulation suite for Microsoft Word.

PubMed

Anzaldi, Laura J; Muñoz-Fernández, Daniel; Erill, Ivan

2012-06-07

The ability to manipulate, edit and process DNA and protein sequences has rapidly become a necessary skill for practicing biologists across a wide swath of disciplines. In spite of this, most everyday sequence manipulation tools are distributed across several programs and web servers, sometimes requiring installation and typically involving frequent switching between applications. To address this problem, here we have developed BioWord, a macro-enabled self-installing template for Microsoft Word documents that integrates an extensive suite of DNA and protein sequence manipulation tools. BioWord is distributed as a single macro-enabled template that self-installs with a single click. After installation, BioWord will open as a tab in the Office ribbon. Biologists can then easily manipulate DNA and protein sequences using a familiar interface and minimize the need to switch between applications. Beyond simple sequence manipulation, BioWord integrates functionality ranging from dyad search and consensus logos to motif discovery and pair-wise alignment. Written in Visual Basic for Applications (VBA) as an open source, object-oriented project, BioWord allows users with varying programming experience to expand and customize the program to better meet their own needs. BioWord integrates a powerful set of tools for biological sequence manipulation within a handy, user-friendly tab in a widely used word processing software package. The use of a simple scripting language and an object-oriented scheme facilitates customization by users and provides a very accessible educational platform for introducing students to basic bioinformatics algorithms.

SDN solutions for switching dedicated long-haul connections: Measurements and comparative analysis

DOE PAGES

Rao, Nageswara S. V.

2016-01-01

We consider a scenario of two sites connected over a dedicated, long-haul connection that must quickly fail-over in response to degradations in host-to-host application performance. The traditional layer-2/3 hot stand-by fail-over solutions do not adequately address the variety of application degradations, and more recent single controller Software Defined Networks (SDN) solutions are not effective for long-haul connections. We present two methods for such a path fail-over using OpenFlow enabled switches: (a) a light-weight method that utilizes host scripts to monitor application performance and dpctl API for switching, and (b) a generic method that uses two OpenDaylight (ODL) controllers and RESTmore » interfaces. For both methods, the restoration dynamics of applications contain significant statistical variations due to the complexities of controllers, north bound interfaces and switches; they, together with the wide variety of vendor implementations, complicate the choice among such solutions. We develop the impulse-response method based on regression functions of performance parameters to provide a rigorous and objective comparison of different solutions. We describe testing results of the two proposed methods, using TCP throughput and connection rtt as main parameters, over a testbed consisting of HP and Cisco switches connected over longhaul connections emulated in hardware by ANUE devices. Lastly, the combination of analytical and experimental results demonstrate that the dpctl method responds seconds faster than the ODL method on average, even though both methods eventually restore original TCP throughput.« less

Hall-MHD and PIC Modeling of the Conduction-to-Opening Transition in a Plasma Opening Switch

NASA Astrophysics Data System (ADS)

Schumer, J. W.; SwanekampDdagger, S. B.; Ottinger, P. F.; Commisso, R. J.; Weber, B. V.

1998-11-01

Utilizing the fast opening characteristics of a plasma opening switch (POS), inductive energy storage devices can generate short-duration high-power pulses (<0.1 μ s, >1 TW) with current rise-times on the order of 10 ns. Plasma redistribution and thinning during the POS conduction phase can be modeled adequately with MHD methods. By including the Hall term in Ohm's Law, MHD methods can simulate plasmas with density gradient scale lengths between c/ω_pe < Ln < c/ω_pi. However, the neglect of electron inertia (c/ω_pe) and space-charge separation (λ_De) by single-fluid theory eventually becomes invalid in small gap regions that form during POS opening. PIC methods are well-suited for low-density plasmas, but are numerically taxed by high-density POS regions. An interface converts MHD (Mach2) output into PIC (Magic) input suitable for validating various transition criteria through comparison of current and density distributions from both methods. We will discuss recent progress in interfacing Hall-MHD and PIC simulations. Work supported by Defense Special Weapons Agency. ^ NRL-NRC Research Associate. hspace0.25in ^ JAYCOR, Vienna, VA 22102.

Working memory costs of task switching.

PubMed

Liefooghe, Baptist; Barrouillet, Pierre; Vandierendonck, André; Camos, Valérie

2008-05-01

Although many accounts of task switching emphasize the importance of working memory as a substantial source of the switch cost, there is a lack of evidence demonstrating that task switching actually places additional demands on working memory. The present study addressed this issue by implementing task switching in continuous complex span tasks with strictly controlled time parameters. A series of 4 experiments demonstrate that recall performance decreased as a function of the number of task switches and that the concurrent load of item maintenance had no influence on task switching. These results indicate that task switching induces a cost on working memory functioning. Implications for theories of task switching, working memory, and resource sharing are addressed.

A Low-G Silicon Inertial Micro-Switch with Enhanced Contact Effect Using Squeeze-Film Damping.

PubMed

Peng, Yingchun; Wen, Zhiyu; Li, Dongling; Shang, Zhengguo

2017-02-16

Contact time is one of the most important properties for inertial micro-switches. However, it is usually less than 20 μs for the switch with rigid electrode, which is difficult for the external circuit to recognize. This issue is traditionally addressed by designing the switch with a keep-close function or flexible electrode. However, the switch with keep-close function requires an additional operation to re-open itself, causing inconvenience for some applications wherein repeated monitoring is needed. The switch with a flexible electrode is usually fabricated by electroplating technology, and it is difficult to realize low-g switches (<50 g) due to inherent fabrication errors. This paper reports a contact enhancement using squeeze-film damping effect for low-g switches. A vertically driven switch with large proof mass and flexible springs was designed based on silicon micromachining, in order to achieve a damping ratio of 2 and a threshold value of 10 g. The proposed contact enhancement was investigated by theoretical and experimental studies. The results show that the damping effect can not only prolong the contact time for the dynamic acceleration load, but also reduce the contact bounce for the quasi-static acceleration load. The contact time under dynamic and quasi-static loads was 40 μs and 570 μs, respectively.

Context Switch Effects on Acquisition and Extinction in Human Predictive Learning

ERIC Educational Resources Information Center

Rosas, Juan M.; Callejas-Aguilera, Jose E.

2006-01-01

Four experiments tested context switch effects on acquisition and extinction in human predictive learning. A context switch impaired probability judgments about a cue-outcome relationship when the cue was trained in a context in which a different cue underwent extinction. The context switch also impaired judgments about a cue trained in a context…

Lamivudine switch therapy in chronic hepatitis B patients achieving undetectable hepatitis B virus DNA after 3 years of entecavir therapy: A prospective, open-label, multicenter study.

PubMed

Yeh, Ming-Lun; Huang, Ching-I; Hsieh, Ming-Yen; Huang, Chung-Feng; Hsieh, Meng-Hsuan; Huang, Jee-Fu; Dai, Chia-Yen; Lin, Zu-Yau; Chen, Shinn-Chern; Yu, Ming-Lung; Chuang, Wan-Long

2016-11-01

The subsequent maintenance therapy in chronic hepatitis B (CHB) patients after long-term viral replication suppression is still uncertain. We aim to evaluate the efficacy of lamivudine (LAM) maintenance therapy in CHB patients achieving undetectable hepatitis B virus (HBV) DNA after 3 years of entecavir (ETV) therapy. Consecutive CHB patients who received at least 3 years of ETV and achieved HBV DNA negativity were allocated either LAM switch therapy or stopped ETV therapy in a prospective, open-label study. Another group of sex- and age-matched patients with continuous ETV therapy for at least 4 years served as historical control group. The primary outcome measurement of the study was relapse of HBV DNA (defined as serum HBV DNA level ≥ 2000 IU/mL). A total of 74 patients, including 42 of LAM switch and 32 of the nonswitch group, were enrolled. There were no significant differences in demographics, except a higher proportion of patients with positive hepatitis B envelope antigen in the nonswitch group at the initiation of ETV therapy. The LAM switch group had significantly lower 1-year relapse rate of HBV within 1 year compared to the nonswitch group (14.3% vs. 75%, p<0.001). However, none of the 48 historical control patients developed relapse of HBV, which was significantly lower than the rate in LAM switch group (p < 0.001). LAM switch was the only factor associated with HBV DNA relapse. In conclusion, continuous long-term potent nucleot(s)ide analogue therapy is mandatory for prevention of viral relapse in CHB patients. Copyright © 2016 Kaohsiung Medical University. Published by Elsevier Taiwan.. All rights reserved.

Report of Workshop on Repetitive Opening Switches

DTIC Science & Technology

1981-06-01

needed. This work must also pay close attention to the poorly understood plasma chemistry in these switches and develop models for discharges and dis...circuit model. Inclusion of plasma chemistry . 2. Compile and measure (when need- ed) fundamental data such as rate coefficients, cross-sec- tions, etc...Include plasma chemistry effects in the code. Conduct literature search. Carry out basic measurements for gas- es and gas mixtures under con

A high power microwave triggered RF opening switch.

PubMed

Beeson, S; Dickens, J; Neuber, A

2015-03-01

A 4-port S-band waveguide structure was designed and fabricated such that a signal of any amplitude (less than 1 MW) can be switched from a normally closed state, <0.5 dB insertion loss (IL), to an open state >30 dB IL by initiating plasma in a gas cell situated at the junction of this waveguide and one propagating a megawatt level magnetron pulse. The 90/10 switching time is as low as 20 ns with a delay of ∼30 ns between the onset of the high power microwave pulse and the initial drop of the signal. Two ports of this device are for the high power triggering pulse while the other two ports are for the triggered signal in a Moreno-like coupler configuration. In order to maintain high isolation, these two sets of waveguides are rotated 90° from each other with a TE111 resonator/plasma cell located at the intersection. This manuscript describes the design and optimization of this structure using COMSOL 4.4 at the design frequency of 2.85 GHz, comparison of simulated scattering parameters with measured "cold tests" (testing without plasma), and finally the temporal waveforms of this device being used to successfully switch a low power CW signal from 2 W to <5 mW on a sub-microsecond timescale.

Outdoor Recreation as a Function of the Urban Housing Environment

ERIC Educational Resources Information Center

Brower, Sidney N.; Williamson, Penelope

1974-01-01

This paper is based upon a survey of open space uses for leisure-time activities in inner city Baltimore. Results of the study indicated that switching emphasis from public park areas to improved semiprivate areas would result in more effective use of open spaces and less expensive maintenance costs. (MA)

Hybrid MPI/OpenMP Implementation of the ORAC Molecular Dynamics Program for Generalized Ensemble and Fast Switching Alchemical Simulations.

PubMed

Procacci, Piero

2016-06-27

We present a new release (6.0β) of the ORAC program [Marsili et al. J. Comput. Chem. 2010, 31, 1106-1116] with a hybrid OpenMP/MPI (open multiprocessing message passing interface) multilevel parallelism tailored for generalized ensemble (GE) and fast switching double annihilation (FS-DAM) nonequilibrium technology aimed at evaluating the binding free energy in drug-receptor system on high performance computing platforms. The production of the GE or FS-DAM trajectories is handled using a weak scaling parallel approach on the MPI level only, while a strong scaling force decomposition scheme is implemented for intranode computations with shared memory access at the OpenMP level. The efficiency, simplicity, and inherent parallel nature of the ORAC implementation of the FS-DAM algorithm, project the code as a possible effective tool for a second generation high throughput virtual screening in drug discovery and design. The code, along with documentation, testing, and ancillary tools, is distributed under the provisions of the General Public License and can be freely downloaded at www.chim.unifi.it/orac .

Cognitive processes and neural basis of language switching: proposal of a new model.

PubMed

Moritz-Gasser, Sylvie; Duffau, Hugues

2009-12-09

Although studies on bilingualism are abundant, cognitive processes and neural foundations of language switching received less attention. The aim of our study is to provide new insights to this still open question: do dedicated region(s) for language switching exist or is this function underlain by a distributed circuit of interconnected brain areas, part of a more general cognitive system? On the basis of recent behavioral, neuroimaging, and brain stimulation studies, we propose an original 'hodological' model of language switching. This process might be subserved by a large-scale cortico-subcortical network, with an executive system (prefrontal cortex, anterior cingulum, caudate nucleus) controlling a more dedicated language subcircuit, which involves postero-temporal areas, supramarginal and angular gyri, Broca's area, and the superior longitudinal fasciculus.

On-chip switch for reconfigurable mode-multiplexing optical network.

PubMed

Sun, Chunlei; Yu, Yu; Chen, Guanyu; Zhang, Xinliang

2016-09-19

The switching and routing is essential for an advanced and reconfigurable optical network, and great efforts have been done for traditional single-mode system. We propose and demonstrate an on-chip switch compatible with mode-division multiplexing system. By controlling the induced phase difference, the functionalities of dynamically routing data channels can be achieved. The proposed switch is experimentally demonstrated with low insertion loss of ~1 dB and high extinction ratio of ~20 dB over the C-band for OFF-ON switchover. For further demonstration, the non-return-to-zero on-off keying signals at 10 Gb/s carried on the two spatial modes are successfully processed. Open and clear eye diagrams can be observed and the bit error rate measurements indicate a good data routing performance.

Rapid fabrication of pressure-driven open-channel microfluidic devices in omniphobic R(F) paper.

PubMed

Glavan, Ana C; Martinez, Ramses V; Maxwell, E Jane; Subramaniam, Anand Bala; Nunes, Rui M D; Soh, Siowling; Whitesides, George M

2013-08-07

This paper describes the fabrication of pressure-driven, open-channel microfluidic systems with lateral dimensions of 45-300 microns carved in omniphobic paper using a craft-cutting tool. Vapor phase silanization with a fluorinated alkyltrichlorosilane renders paper omniphobic, but preserves its high gas permeability and mechanical properties. When sealed with tape, the carved channels form conduits capable of guiding liquid transport in the low-Reynolds number regime (i.e. laminar flow). These devices are compatible with complex fluids such as droplets of water in oil. The combination of omniphobic paper and a craft cutter enables the development of new types of valves and switches, such as "fold valves" and "porous switches," which provide new methods to control fluid flow.

Response to 'Comment on 'Controllable local modification of fractured Nb-doped SrTiO{sub 3} surfaces' [Appl. Phys. Lett. 98, 256102 (2011)'.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chien, T. Y.; Santos, T. S.; Bode, M.

2011-06-20

In their comment, Chen et al. try to argue that the experimentally observed controllable voltage-induced surface modification, which was attributed to a local electric field-induced atom transfer from the surface to the tip, is rather caused by either an oxidation process and/or a resistance change. In this response, we will show that we can rule out these two effects in our experiment. The statements by Chen et al. are based on two arguments: (1) the tip modification after transferring an adatom should alter the dI/dV contrast, which was not seen in our experiments and (2) the vacuum conditions in ourmore » experiment are similar to earlier reports on resistance switching. First, Chen et al. discuss that the adsorption on the tip should alter the topographic contrast, as many papers have reported. In fact, in our experiments we frequently observed tip modifications at high bias voltage. These typically result in slight changes in scanning tunneling spectroscopy data [see, for example, the spectra in Fig. 3(b) in Ref. 4 and Fig. 2(d) of Ref. 5] but only weakly affected the topographic contrast. Second, Chen et al. claim that oxidation is another possible mechanism to explain our experimental observations. To support this claim, they compare our results to an earlier publication showing resistance switching. In fact, the resistance switching mechanism is related to oxygen vacancy migration or local surface oxidation. The mechanism of oxygen vacancy migration requires a 'forming' process with a threshold current in the order of microampere or even milliampere. In our experimental setup, however, we used tunneling currents in the order of 50 pA. Even during surface modification, which was performed at open feedback loop conditions with voltage pulse of up to 3 or -5 V, the maximum transient current did not exceed a few nanoampere. Therefore, we can safely exclude oxygen vacancy migration as a potential mechanism for the observed surface modification. As a second potential mechanism Chen et al. mention a local surface oxidation process. However, the total pressure at high-vacuum conditions used in experiments, where resistance switching was observed (10{sup -7} torr in Ref. 3) is three order magnitude higher than in our experiment performed under ultrahigh vacuum (UHV) conditions (below 10{sup -10} torr). Furthermore, mass spectra measured with a residual gas analyzer show that the main residue gas in our UHV system is hydrogen ({approx} 90%). Water, oxygen, and other oxygen-related gases are negligible with a partial pressure in the order of 10{sup -12} torr range or lower. Therefore, we can also exclude that local oxidation with reactants from the residual gas causes the observed modifications. In addition, in our experiment, the refilling of the modified areas at negative bias could not be observed with fresh tip, even for bias voltages as high as -10 V. In short, the mechanism for the modification on the UHV in situ fractured Nb:SrTiO{sub 3} (Nb-doped Strontium titanate) surfaces with scanning tunneling microscope (STM) tip is different from the mechanisms such as local surface oxidation or filament formation, used to explain the largecurrent induced resistance switching works.« less

Dynamic metabolic modeling of heterotrophic and mixotrophic microalgal growth on fermentative wastes

PubMed Central

Baroukh, Caroline; Turon, Violette; Bernard, Olivier

2017-01-01

Microalgae are promising microorganisms for the production of numerous molecules of interest, such as pigments, proteins or triglycerides that can be turned into biofuels. Heterotrophic or mixotrophic growth on fermentative wastes represents an interesting approach to achieving higher biomass concentrations, while reducing cost and improving the environmental footprint. Fermentative wastes generally consist of a blend of diverse molecules and it is thus crucial to understand microalgal metabolism in such conditions, where switching between substrates might occur. Metabolic modeling has proven to be an efficient tool for understanding metabolism and guiding the optimization of biomass or target molecule production. Here, we focused on the metabolism of Chlorella sorokiniana growing heterotrophically and mixotrophically on acetate and butyrate. The metabolism was represented by 172 metabolic reactions. The DRUM modeling framework with a mildly relaxed quasi-steady-state assumption was used to account for the switching between substrates and the presence of light. Nine experiments were used to calibrate the model and nine experiments for the validation. The model efficiently predicted the experimental data, including the transient behavior during heterotrophic, autotrophic, mixotrophic and diauxic growth. It shows that an accurate model of metabolism can now be constructed, even in dynamic conditions, with the presence of several carbon substrates. It also opens new perspectives for the heterotrophic and mixotrophic use of microalgae, especially for biofuel production from wastes. PMID:28582469

Double slit experiment with quantum detectors: mysteries, meanings, misinterpretations and measurement

NASA Astrophysics Data System (ADS)

Rameez-ul-Islam; Ikram, Manzoor; Hasan Mujtaba, Abid; Abbas, Tasawar

2018-01-01

We propose an idea for symmetric measurements through the famous double slit experiment (DSE) in a new detection scenario. The interferometric setup is complemented here with quantum detectors that switch to an arbitrary superposition after interaction with the arms of the DSE. The envisioned schematics cover the full measurement range, i.e. from the weak to the strong projective situation with selectivity being a smoothly tunable open option, and suggests an alternative methodology for weak measurements based on information overlap from DSE paths. The results, though generally in agreement with the quantum paradigm, raise many questions over the nature of probabilities, the absurdity of the common language for phenomena’s description in the theory and the boundary separating the projective/non-projective measurements, and the related misconceived interpretations. Further, the results impose certain constraints over the hidden variable theories as well as on the repercussions of the weak measurements. Although described as a thought experiment, the proposal can equally be implemented experimentally under a prevailing research scenario.

Optical switches and switching methods

DOEpatents

Doty, Michael

2008-03-04

A device and method for collecting subject responses, particularly during magnetic imaging experiments and testing using a method such as functional MRI. The device comprises a non-metallic input device which is coupled via fiber optic cables to a computer or other data collection device. One or more optical switches transmit the subject's responses. The input device keeps the subject's fingers comfortably aligned with the switches by partially immobilizing the forearm, wrist, and/or hand of the subject. Also a robust nonmetallic switch, particularly for use with the input device and methods for optical switching.

Task Switching in a Hierarchical Task Structure: Evidence for the Fragility of the Task Repetition Benefit

ERIC Educational Resources Information Center

Lien, Mei-Ching; Ruthruff, Eric

2004-01-01

This study examined how task switching is affected by hierarchical task organization. Traditional task-switching studies, which use a constant temporal and spatial distance between each task element (defined as a stimulus requiring a response), promote a flat task structure. Using this approach, Experiment 1 revealed a large switch cost of 238 ms.…

Systems and methods for reducing transient voltage spikes in matrix converters

DOEpatents

Kajouke, Lateef A.; Perisic, Milun; Ransom, Ray M.

2013-06-11

Systems and methods are provided for delivering energy using an energy conversion module that includes one or more switching elements. An exemplary electrical system comprises a DC interface, an AC interface, an isolation module, a first conversion module between the DC interface and the isolation module, and a second conversion module between the AC interface and the isolation module. A control module is configured to operate the first conversion module to provide an injection current to the second conversion module to reduce a magnitude of a current through a switching element of the second conversion module before opening the switching element.

Mechanical coupling in myosin V: a simulation study

PubMed Central

Ovchinnikov, Victor; Trout, Bernhardt L.

2009-01-01

Myosin motor function depends on the interaction between different domains that transmit information from one part of the molecule to another. The inter-domain coupling in myosin V is studied with Restrained Targeted Molecular Dynamics (RTMD) using an all-atom representation in explicit solvent. To elucidate the origin of the conformational change due to the binding of ATP, targeting forces are applied to small sets of atoms (the forcing sets, FS) in the direction of their displacement from the rigor conformation, which has a closed actin-binding cleft, to the post-rigor conformation, in which the cleft is open. The ‘minimal’ FS that results in extensive structural changes in the overall myosin conformation is comprised of the ATP, Switch 1, and the nearby HF, HG and HH helices. Addition of switch 2 to the forcing set is required to achieve a complete opening of the actin-binding cleft. The RTMD simulations reveal the mechanical coupling pathways between (i) the nucleotide-binding pocket (NBP) and the actin-binding cleft, (ii) the NBP and the converter, and (iii) the actin-binding cleft and the converter. Closing of the NBP due to ATP binding is tightly coupled to the opening of the cleft, and leads to the rupture of a key hydrogen bond (F441N/A684O) between switch 2 and the SH1 helix. The actin-binding cleft may mediate the rupture of this bond via a connection between the HW helix, the Relay helix, and Switch 2. The findings are consistent with experimental studies and a recent normal mode analysis. The present method is expected to be useful more generally in studies of inter-domain coupling in proteins. PMID:19853615

Mechanical coupling in myosin V: a simulation study.

PubMed

Ovchinnikov, Victor; Trout, Bernhardt L; Karplus, Martin

2010-01-29

Myosin motor function depends on the interaction between different domains that transmit information from one part of the molecule to another. The interdomain coupling in myosin V is studied with restrained targeted molecular dynamics using an all-atom representation in explicit solvent. To elucidate the origin of the conformational change due to the binding of ATP, targeting forces are applied to small sets of atoms (the forcing sets, FSs) in the direction of their displacement from the rigor conformation, which has a closed actin-binding cleft, to the post-rigor conformation, in which the cleft is open. The "minimal" FS that results in extensive structural changes in the overall myosin conformation is composed of ATP, switch 1, and the nearby HF, HG, and HH helices. Addition of switch 2 to the FS is required to achieve a complete opening of the actin-binding cleft. The restrained targeted molecular dynamics simulations reveal the mechanical coupling pathways between (i) the nucleotide-binding pocket (NBP) and the actin-binding cleft, (ii) the NBP and the converter, and (iii) the actin-binding cleft and the converter. Closing of the NBP due to ATP binding is tightly coupled to the opening of the cleft and leads to the rupture of a key hydrogen bond (F441N/A684O) between switch 2 and the SH1 helix. The actin-binding cleft may mediate the rupture of this bond via a connection between the HW helix, the relay helix, and switch 2. The findings are consistent with experimental studies and a recent normal mode analysis. The present method is expected to be useful more generally in studies of interdomain coupling in proteins.

United States Navy - Canadian forces solid state flight data recorder/crash position locator experiment on the B-720 controlled impact demonstration

NASA Technical Reports Server (NTRS)

Watters, D. M.

1986-01-01

The operation of a radio beacon position locator during and after the remotely controlled transport aircraft is discussed. The radio beacon transmission was actuated and was picked up by the Navy P-3A chase aircraft for a short time, after which reception was lost. The pilot reported that he received a signal on both 121.5 MHz and 243 MHz for a period of approximately 5 seconds. Five minutes after the crash a portable direction finding unit located on the roof of the NASA Dryden Flight Research Facility, 4 miles distant from the crash, was unable to pick up the beacon transmission. The fire crews started fighting the fires approximately 90 seconds after the time of impact. Navy personnel access to the crash site was allowed on the morning of December 2, 1984. Radio beacon locator was found resting top side up, 15 feet forward and 13 feet perpendicular from the tray location the starboard side of the aircraft. An immediate inspection indicated the airfoil suffered moderate fire damage with paint peeling but not intumescing. The visual marker strobe lamp housings were intact but extensively burned such that it was impossible to see if the lamps had survived. The airfoil suffered minor structural damage, with assorted dents, etc. The extended plunger on the ARU-21 release unit indicated that the pyrotechnic deployment system operated. The radio beacon base (tray) suffered some heat and fire damage, and was charred and blackened by smoke. The frangible switch in the nose survived and the switch in the belly was recovered and found to have actuated. It is assumed that this switch fired the ARU-21 squib. There were no other release switches installed in the normally open system in the aircraft.

Single-molecule detection of dihydroazulene photo-thermal reaction using break junction technique

NASA Astrophysics Data System (ADS)

Huang, Cancan; Jevric, Martyn; Borges, Anders; Olsen, Stine T.; Hamill, Joseph M.; Zheng, Jue-Ting; Yang, Yang; Rudnev, Alexander; Baghernejad, Masoud; Broekmann, Peter; Petersen, Anne Ugleholdt; Wandlowski, Thomas; Mikkelsen, Kurt V.; Solomon, Gemma C.; Brøndsted Nielsen, Mogens; Hong, Wenjing

2017-05-01

Charge transport by tunnelling is one of the most ubiquitous elementary processes in nature. Small structural changes in a molecular junction can lead to significant difference in the single-molecule electronic properties, offering a tremendous opportunity to examine a reaction on the single-molecule scale by monitoring the conductance changes. Here, we explore the potential of the single-molecule break junction technique in the detection of photo-thermal reaction processes of a photochromic dihydroazulene/vinylheptafulvene system. Statistical analysis of the break junction experiments provides a quantitative approach for probing the reaction kinetics and reversibility, including the occurrence of isomerization during the reaction. The product ratios observed when switching the system in the junction does not follow those observed in solution studies (both experiment and theory), suggesting that the junction environment was perturbing the process significantly. This study opens the possibility of using nano-structured environments like molecular junctions to tailor product ratios in chemical reactions.

Treatment switch guided by HIV-1 genotyping in Brazil.

PubMed

Tupinambás, Unaí; Ribeiro, Flávia Andrade; Aleixo, Agdemir; Greco, Dirceu

2006-04-01

We assessed the performance of HIV-1 genotyping tests in rescue therapy. Patients were divided into two groups: group 1 (genotyped), included those switching to new antiretroviral drugs based on HIV-1 genotyping data, and group 2 (standard of care -SOC), comprised those in rescue therapy who had not used this test. This was an open and non-randomized study, with 74 patients, followed up for a mean period of 12 months, from February 2002 to May 2003. The groups differed in the duration of antiretroviral use, experience with diverse drug classes (non-nucleoside reverse transcriptase inhibitors and protease inhibitors) and viral load <2.6 log10 copies/mL at any time during treatment. In 23 patients (group 1), the switch in antiretroviral (ARV) regimen was based on genotyping data; this test was not used for 51 patients (group 2). Two CD4 + lymphocyte counts and viral load counts were made for each patient during the study. Data from the pharmacy where patients received antiretroviral agents, medical charts, and direct interviews with patients to assess compliance to treatment, were analyzed. In the genotyped group, the average drop in viral load was 2.8 log10, compared with a 1.5 log10 difference in group 2; the difference was significant in the first assessment performed six months after switching (p=0.001). Considering the patients with viral load < 2.6 log10 (400 copies/mL) after switching, the patients in group 1 had a better performance in the first assessment (73.9% versus 31.1% in groups 1 and 2, respectively); this difference was significant (p=0.001). In multivariate analysis, the variables associated with a greater drop in viral load in the first assessment were the patients whose switching was based on genotyping (group 1), those with a past history of viral load < 2.6 log10 and correct use of antiretroviral agents. In conclusion, the genotyping test and adherence were found to be independent factors for success in the management of patients who failed treatment.

Contextual control of instrumental actions and habits

PubMed Central

Thrailkill, Eric A.; Bouton, Mark E.

2014-01-01

After a relatively small amount of training, instrumental behavior is thought to be an action under the control of the motivational status of its goal or reinforcer. After more extended training, behavior can become habitual and insensitive to changes in reinforcer value. Recently, instrumental responding has been shown to weaken when tested outside of the training context. The present experiments compared the sensitivity of instrumental responding in rats to a context switch after training procedures that might differentially generate actions or habits. In Experiment 1, lever pressing was decremented in a new context after either short, medium, or long periods of training on either random-ratio or yoked random-interval reinforcement schedules. Experiment 2 found that more minimally-trained responding was also sensitive to a context switch. Moreover, Experiment 3 showed that when the goal-directed component of responding was removed by devaluing the reinforcer, the residual responding that remained was still sensitive to the change of context. Goal-directed responding, in contrast, transferred across contexts. Experiment 4 then found that after extensive training, a habit that was insensitive to reinforcer devaluation was still decremented by a context switch. Overall, the results suggest that a context switch primarily influences instrumental habit rather than action. In addition, even a response that has received relatively minimal training may have a habit component that is insensitive to reinforcer devaluation but sensitive to the effects of a context switch. PMID:25706547

Estimation of snow line elevation changes from MODIS snow cover data

NASA Astrophysics Data System (ADS)

Parajka, Juraj; Bezak, Nejc; Burkhart, John; Holko, Ladislav; Hundecha, Yeshewa; Krajči, Pavel; Mangini, Walter; Molnar, Peter; Sensoy, Aynur; Riboust, Phillippe; Rizzi, Jonathan; Thirel, Guillaume; Arheimer, Berit

2017-04-01

This contribution evaluates changes in snowline elevation during snowmelt runoff events in selected basins from Austria, France, Norway, Slovakia, Slovenia, Sweden, Switzerland and Turkey. The main objectives are to investigate the spatial and temporal differences in regional snowline elevation (RSLE) across Europe and to discuss the factors which control its change. The analysis is performed in two steps. In the first, the regional snowline elevation is processed from daily MODIS snow cover data (MOD10A1) by using the methodology of Krajčí et al., (2014). In the second step, the changes in RSLE are analysed for selected flood events in the period 2000-2015. The snowmelt runoff events are extracted from Catalogue of identified flood peaks from GRDC dataset (FLOOD TYPE experiment) available at http://www.water-switch-on.eu/sip-webclient/byod/#/resource/12056. The results will be discussed in terms of: (a) availability and potential of MODIS snow cover data for identifying RSLE changes during snowmelt runoff events, (b) spatial and temporal patterns of RSLE changes across Europe and (c) factor controlling the RSLE change. The analysis is performed as an experiment in Virtual Water Science Laboratory of SWITCH-ON Project (http://www.water-switch-on.eu/). All data, tools and results of the analysis will be open and accessible through the Spatial Information Platform of the Project (http://www.water-switch-on.eu/sip-webclient/byod/). We believe that such strategy will allow to improve and forward comparative research and cooperation between different partners in hydrology (Ceola et al., 2015). References Ceola, S., Arheimer, B., Baratti, E., Blöschl, G., Capell, R., Castellarin, A., Freer, J., Han, D., Hrachowitz, M., Hundecha, Y., Hutton, C., Lindström, G., Montanari, A., Nijzink, R., Parajka, J., Toth, E., Viglione, A., and Wagener, T.: Virtual laboratories: new opportunities for collaborative water science, Hydrol. Earth Syst. Sci., 19, 2101-2117, doi:10.5194/hess-19-2101-2015, 2015. Krajčí, P., Holko, L., Perdigão, R.A.P., Parajka, J., Estimation of regional snowline elevation (RSLE) from MODIS images for seasonally snow covered mountain basins,2014,Journal of Hydrology,519,1769-1778

Electronic Warfare Training Analysis.

DTIC Science & Technology

1972-01-01

associated have a question, the instructor can select a with it one plugboard and two program switch previously presented training step sequence by drums...operates in conjunction with Located on the control panel. an overlay, programmed plugboard , and two 1-13. JACK PIN CONTROL. The device also program...drums. Supplied with Device 3CI27A are one plugboard and two program switch has means for student participation. An open- *.- . . ,_ . cLruZuiL Iwo-pote

Method and apparatus for monitoring motor operated valve motor output torque and power at valve seating

DOEpatents

Casada, D.A.

1996-01-16

A method and apparatus are provided for monitoring a motor operated valve during the brief period when the valve seats and the torque switch trips to deenergize the valve motor. The method uses voltage measurements on the load side of a deenergizing switch that opens to deenergize the motor to determine, among other things, final motor rotational speed and the decelerating torque at motor deenergization. 14 figs.

Method and apparatus for monitoring motor operated valve motor output torque and power at valve seating

DOEpatents

Casada, Donald A.

1996-01-01

A method and apparatus are provided for monitoring a motor operated valve during the brief period when the valve seats and the torque switch trips to deenergize the valve motor. The method uses voltage measurements on the load side of a deenergizing switch that opens to deenergize the motor to determine, among other things, final motor rotational speed and the decelerating torque at motor deenergization.

Sustainable Efficacy of Switching From Intravenous to Subcutaneous Tocilizumab Monotherapy in Patients With Rheumatoid Arthritis.

PubMed

Ogata, Atsushi; Atsumi, Tatsuya; Fukuda, Takaaki; Hirabayashi, Yasuhiko; Inaba, Masaaki; Ishiguro, Naoki; Kai, Motokazu; Kawabata, Daisuke; Kida, Daihei; Kohsaka, Hitoshi; Matsumura, Ryutaro; Minota, Seiji; Mukai, Masaya; Sumida, Takayuki; Takasugi, Kiyoshi; Tamaki, Shigenori; Takeuchi, Tsutomu; Ueda, Atsuhisa; Yamamoto, Kazuhiko; Yamanaka, Hisashi; Yoshifuji, Hajime; Nomura, Akira

2015-10-01

To evaluate the efficacy and safety of switching from intravenous (IV) tocilizumab (TCZ) to subcutaneous (SC) TCZ monotherapy in rheumatoid arthritis patients. Patients who had completed 24 weeks of TCZ-SC (162 mg/2 weeks) or TCZ-IV (8 mg/kg/4 weeks) monotherapy in the double-blind period of the MUSASHI study were enrolled in an 84-week open-label extension period. All received TCZ-SC (162 mg/2 weeks) monotherapy. Effects of the IV to SC switch were evaluated at week 36 (12 weeks after switching). Overall, 319 patients received ≥1 dose of TCZ-SC during the open-label extension period; 160 switched from TCZ-IV to TCZ-SC (TCZ IV/SC) and 159 continued TCZ-SC (TCZ SC/SC). Disease Activity Score in 28 joints using the erythrocyte sedimentation rate clinical remission rates were 62.5% (100 of 160) for TCZ IV/SC and 50.0% (79 of 158) for TCZ SC/SC at week 24, and were maintained at 62.5% (100 of 160) and 57.0% (90 of 158), respectively, at week 36. In the TCZ IV/SC group, 9% of patients (9 of 100) who had achieved remission at week 24 could not maintain remission at week 36. In TCZ IV/SC patients weighing ≥70 kg, the percentage with a sufficient serum TCZ concentration (≥1 μg/ml) decreased from 90.9% (10 of 11) at week 24 to 45.5% (5 of 11) at week 36. Overall safety profiles were similar in TCZ IV/SC and TCZ SC/SC except for mild injection site reactions in TCZ IV/SC. Efficacy is adequately maintained in most patients switching from TCZ-IV (8 mg/kg/4 weeks) to TCZ-SC (162 mg/2 weeks) monotherapy. Patients receiving TCZ-IV can switch to TCZ-SC without serious safety concerns. Clinical efficacy may be reduced after switching in some patients with high body weight. © 2015 The Authors. Arthritis Care & Research is published by Wiley Periodicals, Inc. on behalf of the American College of Rheumatology.

Metabolic impact of switching antipsychotic therapy to aripiprazole after weight gain: a pilot study.

PubMed

Kim, Sun H; Ivanova, Oxana; Abbasi, Fahim A; Lamendola, Cindy A; Reaven, Gerald M; Glick, Ira D

2007-08-01

Switching antipsychotic regimen to agents with low weight gain potential has been suggested in patients who gain excessive weight on their antipsychotic therapy. In an open-label pilot study, we evaluated the metabolic and psychiatric efficacy of switching to aripiprazole in 15 (9 men, 6 women) outpatients with schizophrenia who had gained at least 10 kg on their previous antipsychotic regimen. Individuals had evaluation of glucose tolerance, insulin resistance (insulin suppression test), lipid concentrations, and psychiatric status before and after switching to aripiprazole for 4 months. A third of the individuals could not psychiatrically tolerate switching to aripiprazole. In the remaining individuals, psychiatric symptoms significantly improved with decline in Clinical Global Impression Scale (by 26%, P = 0.015) and Positive and Negative Syndrome Scale (by 22%, P = 0.023). Switching to aripiprazole did not alter weight or metabolic outcomes (fasting glucose, insulin resistance, and lipid concentrations) in the patients of whom 73% were insulin resistant and 47% had impaired or diabetic glucose tolerance at baseline. In conclusion, switching to aripiprazole alone does not ameliorate the highly prevalent metabolic abnormalities in the schizophrenia population who have gained weight on other second generation antipsychotic medications.

Open-loop correction for an eddy current dominated beam-switching magnet.

PubMed

Koseki, K; Nakayama, H; Tawada, M

2014-04-01

A beam-switching magnet and the pulsed power supply it requires have been developed for the Japan Proton Accelerator Research Complex. To switch bunched proton beams, the dipole magnetic field must reach its maximum value within 40 ms. In addition, the field flatness should be less than 5 × 10(-4) to guide each bunched beam to the designed orbit. From a magnetic field measurement by using a long search coil, it was found that an eddy current in the thick endplates and laminated core disturbs the rise of the magnetic field. The eddy current also deteriorates the field flatness over the required flat-top period. The measured field flatness was 5 × 10(-3). By using a double-exponential equation to approximate the measured magnetic field, a compensation pattern for the eddy current was calculated. The integrated magnetic field was measured while using the newly developed open-loop compensation system. A field flatness of less than 5 × 10(-4), which is an acceptable value, was achieved.

Open-loop correction for an eddy current dominated beam-switching magnet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koseki, K., E-mail: kunio.koseki@kek.jp; Nakayama, H.; Tawada, M.

2014-04-15

A beam-switching magnet and the pulsed power supply it requires have been developed for the Japan Proton Accelerator Research Complex. To switch bunched proton beams, the dipole magnetic field must reach its maximum value within 40 ms. In addition, the field flatness should be less than 5 × 10{sup −4} to guide each bunched beam to the designed orbit. From a magnetic field measurement by using a long search coil, it was found that an eddy current in the thick endplates and laminated core disturbs the rise of the magnetic field. The eddy current also deteriorates the field flatness over the requiredmore » flat-top period. The measured field flatness was 5 × 10{sup −3}. By using a double-exponential equation to approximate the measured magnetic field, a compensation pattern for the eddy current was calculated. The integrated magnetic field was measured while using the newly developed open-loop compensation system. A field flatness of less than 5 × 10{sup −4}, which is an acceptable value, was achieved.« less

Improvement of Diurnal Blood Pressure Variation by Azilsartan.

PubMed

Okamura, Keisuke; Shirai, Kazuyuki; Okuda, Tetsu; Urata, Hidenori

2018-01-01

Azilsartan is an angiotensin II receptor blocker with a potent antihypertensive effect. In a multicenter, prospective, open-label study, 265 patients with poor blood pressure control despite treatment with other angiotensin II receptor blockers were switched to 20 mg/day of azilsartan (patients on standard dosages) or 40 mg/day of azilsartan (patients on high dosages). Blood pressure was 149/83 mm Hg before switching and was significantly reduced from 1 month after switching until final assessment (132/76 mm Hg, P < 0.001). The pulse rate was 72/min before switching and increased significantly from 3 months after switching until final assessment (74/min, P < 0.005). A significant decrease of home morning systolic and diastolic pressure was observed from 1 and 3 months, respectively. Home morning blood pressure was 143/82 mm Hg before switching and 130/76 mm Hg at final assessment (P < 0.01). The morning-evening difference of systolic blood pressure decreased from 14.6 to 6.6 mm Hg after switching (P = 0.09). The estimated glomerular filtration rate was significantly decreased at 3, 6, and 12 months after switching, and serum uric acid was significantly increased at 12 months. No serious adverse events occurred. Azilsartan significantly reduced the blood pressure and decreased diurnal variation in patients responding poorly to other angiotensin II receptor blockers.

Optimization of micromachined membrane switches

NASA Astrophysics Data System (ADS)

Hiltmann, Kai; Lang, Walter

1997-09-01

We have determined the minimum dimensions for micromachined membrane switches in several experiments, both regarding the strength of the membranes themselves and the elongations required for safe switching performance. Based on these data, pressure switches for voltages of 10 - 100 V were made as single and multiple elements and tested. Test results, with scatter of pressure threshold data in the ten per cent range, prove very encouraging for further development.

Shoe drop reduction influences the lower limb biomechanics of children tennis players during an open stance forehand: A longitudinal study.

PubMed

Herbaut, Alexis; Simoneau-Buessinger, Emilie; Barbier, Franck; Gillet, Christophe; Roux, Maxime; Guéguen, Nils; Chavet, Pascale

2017-11-01

Compared to traditional tennis shoes, using 0-drop shoes was shown to induce an immediate switch from rear- to forefoot strike pattern to perform an open stance tennis forehand for 30% of children tennis players. The purpose of the study was to examine the long-term effects of a gradual reduction in the shoe drop on the biomechanics of children tennis players performing open stance forehands. Thirty children tennis players participated in 2 laboratory biomechanical test sessions (intermediate: +4 months and final: +8 months) after an inclusion visit where they were randomly assigned to control (CON) or experimental (EXP) group. CON received 12-mm-drop shoes twice, whereas EXP received 8 mm then 4-mm-drop shoes. Strike index indicated that all CON were rearfoot strikers in intermediate and final test sessions. All EXP were rearfoot strikers in intermediate test session, but half the group switched towards a forefoot strike pattern in final test session. This switch resulted in a decreased loading rate of the ground reaction force (-73%, p = .005) but increased peak ankle plantarflexors moment (+47%, p = .050) and peak ankle power absorption (+107%, p = .005) for these participants compared with CON. Biomechanical changes associated with the long-term use of partial minimalist shoes suggest a reduction in heel compressive forces but an increase in Achilles tendon tensile forces.

Switch from oral pramipexole or ropinirole to rotigotine transdermal system in advanced Parkinson's disease: an open-label study.

PubMed

Chung, Sun Ju; Kim, Jong-Min; Kim, Jae Woo; Jeon, Beom Seok; Singh, Pritibha; Thierfelder, Stephan; Ikeda, Junji; Bauer, Lars

2015-05-01

Investigate safety, feasibility and efficacy of switching therapy in patients with advanced-stage Parkinson's disease (PD) inadequately controlled with pramipexole (≤ 3.5 mg/day) or ropinirole (≤ 14 mg/day) to rotigotine transdermal system (≤ 14 mg/24 h; dose adjustments ≤ 16 mg/24 h permitted). PD0009 (ClinicalTrials.gov: NCT01711866) was an open-label study in patients with advanced-stage PD receiving levodopa, and experiencing sleep disturbance or early-morning motor impairment. Pramipexole/ropinirole was switched to equivalent dose rotigotine overnight or in two stages. During the 4-week treatment period rotigotine dose adjustments were permitted (up to 16 mg/24 h). Primary variable: Clinical Global Impressions (CGI) item 4: side effects (assessing safety) at end of treatment. 79/87 (91%) patients completed the study; 2 (2%) withdrew due to adverse events (AEs). Most (84; 97%) had CGI item 4 score < 3 indicating switch did not interfere with functioning; three experienced drug-related AEs interfering with functioning (score = 3). 62% patients improved on Patient Global Impression of Change, assessing effectiveness. AEs occurring ≥ 5%: application site pruritus (10%), application site erythema (7%), dizziness (7%), dyskinesia (7%), erythema (6%), pruritus (6%). Unified Parkinson's Disease Rating Scale II and III, Parkinson's Disease Sleep Scale-2 and Pittsburgh Sleep Quality Index were unchanged. Numerical improvements in 'off' time, awakenings and nocturias were observed. Switch from pramipexole or ropinirole to rotigotine (up to 14 mg/24 h) was feasible and possibly associated with some benefit.

High-Power Actuation from Molecular Photoswitches in Enantiomerically Paired Soft Springs.

PubMed

Aßhoff, Sarah J; Lancia, Federico; Iamsaard, Supitchaya; Matt, Benjamin; Kudernac, Tibor; Fletcher, Stephen P; Katsonis, Nathalie

2017-03-13

Motion in plants often relies on dynamic helical systems as seen in coiling tendrils, spasmoneme springs, and the opening of chiral seedpods. Developing nanotechnology that would allow molecular-level phenomena to drive such movements in artificial systems remains a scientific challenge. Herein, we describe a soft device that uses nanoscale information to mimic seedpod opening. The system exploits a fundamental mechanism of stimuli-responsive deformation in plants, namely that inflexible elements with specific orientations are integrated into a stimuli-responsive matrix. The device is operated by isomerization of a light-responsive molecular switch that drives the twisting of strips of liquid-crystal elastomers. The strips twist in opposite directions and work against each other until the pod pops open from stress. This mechanism allows the photoisomerization of molecular switches to stimulate rapid shape changes at the macroscale and thus to maximize actuation power. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Replacing the Measles Ten-Dose Vaccine Presentation with the Single-Dose Presentation in Thailand

PubMed Central

Lee, Bruce Y.; Assi, Tina-Marie; Rookkapan, Korngamon; Connor, Diana L.; Rajgopal, Jayant; Sornsrivichai, Vorasith; Brown, Shawn T.; Welling, Joel S.; Norman, Bryan A.; Chen, Sheng-I; Bailey, Rachel R.; Wiringa, Ann E.; Wateska, Angela R.; Jana, Anirban; Van Panhuis, Willem G.; Burke, Donald S.

2011-01-01

Introduced to minimize open vial wastage, single-dose vaccine vials require more storage space and therefore may affect vaccine supply chains (i.e., the series of steps and processes entailed to deliver vaccines from manufacturers to patients). We developed a computational model of Thailand’s Trang province vaccine supply chain to analyze the effects of switching from a ten-dose measles vaccine presentation to each of the following: a single-dose Measles-Mumps-Rubella vaccine (which Thailand is currently considering) and a single-dose measles vaccine. While the Trang province vaccine supply chain would generally have enough storage and transport capacity to accommodate the switches, the added volume could push some locations’ storage and transport space utilization close to their limits. Single-dose vaccines would allow for more precise ordering and decrease open vial waste, but decrease reserves for unanticipated demand. Moreover, the added disposal and administration costs could far outweigh the costs saved from preventing open vial wastage. PMID:21439313

AEA Cell-Bypass-Switch Activation: An Update

NASA Technical Reports Server (NTRS)

Keys, Denney; Rao, Gopalakrishna M.; Wannemacher, Harry

2002-01-01

The objectives of this project included the following: (1) verify the performance of AEA cell bypass protection device (CBPD) under simulated EOS-Aqua/Aura flight hardware configuration; (2) assess the safety of the hardware under an inadvertent firing of CBPD switch, as well as the closing of CBPD; and (3) confirm that the mode of operation of CBPD switch is the formation of a continuous low impedance path (a homogeneous low melting point alloy). The nominal performance of AEA CBPD under flight operating conditions (vacuum except zero-G, and high impedance cell) has been demonstrated. There is no evidence of cell rupture or excessive heat production during or after CBPD switch activation under simulated high cell impedance (open-circuit cell failure mode). The formation of a continuous low impedance path (a homogeneous low melting point alloy) has been confirmed.

Face matching in a long task: enforced rest and desk-switching cannot maintain identification accuracy

PubMed Central

Alenezi, Hamood M.; Fysh, Matthew C.; Johnston, Robert A.

2015-01-01

In face matching, observers have to decide whether two photographs depict the same person or different people. This task is not only remarkably difficult but accuracy declines further during prolonged testing. The current study investigated whether this decline in long tasks can be eliminated with regular rest-breaks (Experiment 1) or room-switching (Experiment 2). Both experiments replicated the accuracy decline for long face-matching tasks and showed that this could not be eliminated with rest or room-switching. These findings suggest that person identification in applied settings, such as passport control, might be particularly error-prone due to the long and repetitive nature of the task. The experiments also show that it is difficult to counteract these problems. PMID:26312179

Evidence against mood-congruent attentional bias in Major Depressive Disorder.

PubMed

Cheng, Philip; Preston, Stephanie D; Jonides, John; Mohr, Alicia Hofelich; Thummala, Kirti; Casement, Melynda; Hsing, Courtney; Deldin, Patricia J

2015-12-15

Depression is consistently associated with biased retrieval and interpretation of affective stimuli, but evidence for depressive bias in earlier cognitive processing, such as attention, is mixed. In five separate experiments, individuals with depression (three experiments with clinically diagnosed major depression, two experiments with dysphoria measured via the Beck Depression Inventory) completed three tasks designed to elicit depressive biases in attention, including selective attention, attentional switching, and attentional inhibition. Selective attention was measured using a modified emotional Stroop task, while attentional switching and inhibition was examined via an emotional task-switching paradigm and an emotional counter task. Results across five different experiments indicate that individuals with depression perform comparably with healthy controls, providing corroboration that depression is not characterized by biases in attentional processes. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Nanocrystalline Si pathway induced unipolar resistive switching behavior from annealed Si-rich SiNx/SiNy multilayers

NASA Astrophysics Data System (ADS)

Jiang, Xiaofan; Ma, Zhongyuan; Yang, Huafeng; Yu, Jie; Wang, Wen; Zhang, Wenping; Li, Wei; Xu, Jun; Xu, Ling; Chen, Kunji; Huang, Xinfan; Feng, Duan

2014-09-01

Adding a resistive switching functionality to a silicon microelectronic chip is a new challenge in materials research. Here, we demonstrate that unipolar and electrode-independent resistive switching effects can be realized in the annealed Si-rich SiNx/SiNy multilayers with high on/off ratio of 109. High resolution transmission electron microscopy reveals that for the high resistance state broken pathways composed of discrete nanocrystalline silicon (nc-Si) exist in the Si nitride multilayers. While for the low resistance state the discrete nc-Si regions is connected, forming continuous nc-Si pathways. Based on the analysis of the temperature dependent I-V characteristics and HRTEM photos, we found that the break-and-bridge evolution of nc-Si pathway is the origin of resistive switching memory behavior. Our findings provide insights into the mechanism of the resistive switching behavior in nc-Si films, opening a way for it to be utilized as a material in Si-based memories.

45^○ sign switching of effective exchange bias due to competing anisotropies in fully epitaxial Co₃FeN/MnN bilayers.

PubMed

Hajiri, Tetsuya; Yoshida, Takuya; Filianina, Mariia; Jaiswal, Samridh; Borie, Benjamin; Asano, H; Zabel, Hartmut; Klaui, Mathias

2017-11-20

We report an unusual angular-dependent exchange bias effect in ferromagnet/antiferromagnet bilayers, where both ferromagnet and antiferromagnet are epitaxially grown. Numerical model calculations predict an approximately 45$^\\circ$ period for the sign switching of the exchange-bias field, depending on the ratio between magnetocrystalline anisotropy and exchange-coupling constant. The switching of the sign is indicative of a competition between a fourfold magnetocrystalline anisotropy of the ferromagnet and a unidirectional anisotropy field of the exchange coupling. This predicted unusual angular-dependent exchange bias and its magnetization switching process are confirmed by measurements on fully epitaxial Co$_3$FeN/MnN bilayers by longitudinal and transverse magneto-optic Kerr effect magnetometry. These results provide a deeper understanding of the exchange coupling phenomena in fully epitaxial bilayers with tailored materials and open up a complex switching energy landscape engineering by anisotropies. © 2017 IOP Publishing Ltd.

Plastic Transition to Switch Nonlinear Optical Properties Showing the Record High Contrast in a Single-Component Molecular Crystal.

PubMed

Sun, Zhihua; Chen, Tianliang; Liu, Xitao; Hong, Maochun; Luo, Junhua

2015-12-23

To switch bulk nonlinear optical (NLO) effects represents an exciting new branch of NLO material science, whereas it remains a great challenge to achieve high contrast for "on/off" of quadratic NLO effects in crystalline materials. Here, we report the supereminent NLO-switching behaviors of a single-component plastic crystal, 2-(hydroxymethyl)-2-nitro-1,3-propanediol (1), which shows a record high contrast of at least ∼150, exceeding all the known crystalline switches. Such a breakthrough is clearly elucidated from the slowing down of highly isotropic molecular motions during plastic-to-rigid transition. The deep understanding of its intrinsic plasticity and superior NLO property allows the construction of a feasible switching mechanism. As a unique class of substances with short-range disorder embedded in long-range ordered crystalline lattice, plastic crystals enable response to external stimuli and fulfill specific photoelectric functions, which open a newly conceptual avenue for the designing of new functional materials.

Conception, fabrication and characterization of a silicon based MEMS inertial switch with a threshold value of 5 g

NASA Astrophysics Data System (ADS)

Zhang, Fengtian; Wang, Chao; Yuan, Mingquan; Tang, Bin; Xiong, Zhuang

2017-12-01

Most of the MEMS inertial switches developed in recent years are intended for shock and impact sensing with a threshold value above 50 g. In order to follow the requirement of detecting linear acceleration signal at low-g level, a silicon based MEMS inertial switch with a threshold value of 5 g was designed, fabricated and characterized. The switch consisted of a large proof mass, supported by circular spiral springs. An analytical model of the structure stiffness of the proposed switch was derived and verified by finite-element simulation. The structure fabrication was based on a customized double-buried layer silicon-on-insulator wafer and encapsulated by glass wafers. The centrifugal experiment and nanoindentation experiment were performed to measure the threshold value as well as the structure stiffness. The actual threshold values were measured to be 0.1-0.3 g lower than the pre-designed value of 5 g due to the dimension loss during non-contact lithography processing. Concerning the reliability assessment, a series of environmental experiments were conducted and the switches remained operational without excessive errors. However, both the random vibration and the shock tests indicate that the metal particles generated during collision of contact parts might affect the contact reliability and long-time stability. According to the conclusion reached in this report, an attentive study on switch contact behavior should be included in future research.

Decomposing Task-Switching Costs with the Diffusion Model

ERIC Educational Resources Information Center

Schmitz, Florian; Voss, Andreas

2012-01-01

In four experiments, task-switching processes were investigated with variants of the alternating runs paradigm and the explicit cueing paradigm. The classical diffusion model for binary decisions (Ratcliff, 1978) was used to dissociate different components of task-switching costs. Findings can be reconciled with the view that task-switching…

Energy stores and switches for rail-launcher systems

NASA Technical Reports Server (NTRS)

Weldon, W. F.; Zowarka, R. C.; Marshall, R. A.

1983-01-01

An overview of existing switch and power supply technology applicable to space launch, a new candidate pulsed power supply for Earth-to-space rail launcher duty, the inverse railgun flux compressor, and a set of switching experiments to study further the feasibility of Earth-to-space launch are discussed.

The Effect of Hierarchical Task Representations on Task Selection in Voluntary Task Switching

ERIC Educational Resources Information Center

Weaver, Starla M.; Arrington, Catherine M.

2013-01-01

The current study explored the potential for hierarchical representations to influence action selection during voluntary task switching. Participants switched between 4 individual task elements. In Experiment 1, participants were encouraged to represent the task elements as grouped within a hierarchy based on experimental manipulations of varying…

Language Switching in the Production of Phrases

ERIC Educational Resources Information Center

Tarlowski, Andrzej; Wodniecka, Zofia; Marzecova, Anna

2013-01-01

The language switching task has provided a useful insight into how bilinguals produce language. So far, however, the studies using this method have been limited to lexical access. The present study provides empirical evidence on language switching in the production of simple grammar structures. In the reported experiment, Polish-English unbalanced…

Energy stores and switches for rail-launcher systems

NASA Astrophysics Data System (ADS)

Weldon, W. F.; Zowarka, R. C.; Marshall, R. A.

An overview of existing switch and power supply technology applicable to space launch, a new candidate pulsed power supply for Earth-to-space rail launcher duty, the inverse railgun flux compressor, and a set of switching experiments to study further the feasibility of Earth-to-space launch are discussed.

Visual Confirmation of Voice Takeoff Clearance (VICON) Operational Evaluation. Volume 2. Operations and Maintenance Manual

DTIC Science & Technology

1981-02-01

cabinet and the field. The momentary contacts from the switches of the control panel trigger the respective circuits in module I. This circuit then... module (approximately 40 milliamperes at 70-100 detector, filter, threshold circuit and alarm relay. A block volts) Into microwave energy at X-band...advantageous to use different N.C. Terminals. NOTE: If open circuit tamper switch is modulation frequencies on links operating within close prox

Circuit breaker lock out assembly

DOEpatents

Gordy, W.T.

1983-05-18

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.

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.

Self energized air core superconducting (SEAC) motor

NASA Astrophysics Data System (ADS)

Hilal, M. A.; Huang, X.; Lloyd, J. D.; Crapo, A. D.

1991-03-01

The SEAC motor described utilizes superconductive windings both for the stator and the rotor and operates the same way as a conventional motor by supplying power to the stator. The rotor of a simple SEAC motor has a small and a large winding and two switches. The axes of the two rotor windings are normal to each other. The rotor is initially stationary, and the windings are exposed to the rotating stator field. Flux pumping is employed to charge the rotor windings. As the field rotates by 180 deg from being parallel to the axis of the small winding of the rotor, a switch connected in series with the windings automatically opens, allowing the magnetic flux to penetrate the winding. The switch is closed during most of the other half of the cycle. The flux trapped in the small winding is partially transferred to the larger rotor winding by opening another switch, which results in series connection of the two windings. This results in charging the large winding and in accelerating the rotor to reach the rotating field angular velocity. Current decay will not take place, since it will automatically trigger flux pumping and recharging of the windings. The use of superconductive windings will also make it feasible to operate at high magnetic field, thus eliminating the need for using iron laminations to magnetically link the rotor and the stator windings.

Long-term weight loss observed with olanzapine orally disintegrating tablets in overweight patients with chronic schizophrenia. A 1 year open-label, prospective trial.

PubMed

Chawla, Bharat; Luxton-Andrew, Heather

2008-04-01

To investigate the long-term weight loss outcomes during usual clinical practice after switching from olanzapine standard oral tablet (SOT) to olanzapine orally disintegrating tablets (ODT). In this open-label prospective study, 26 patients with schizophrenia who were clinically stable on olanzapine SOT treatment were switched to olanzapine ODT. All other aspects of treatment remained constant. Weight was recorded at 3, 6, and 12 months. Patients incurred an average weight loss of 2.7 +/- 0.7 kg (p = 0.001) after switching patients from olanzapine SOT to olanzapine ODT at 12 months. Peak weight loss was observed at 6 months; however, significant weight loss was achieved as early as 3 months. The majority (81.9%) of patients lost weight, while 18.1% had no weight change or weight gain. Body mass index (BMI) significantly decreased by 1.0 +/- 0.3 kg/m(2) (p = 0.001). Interestingly, patients treated with higher doses of olanzapine (> or = 20 mg) incurred a greater weight loss of their body weight (5.6%), compared to those treated with lower doses (< 20 mg), who lost 1.9% of their body weight (p = 0.04). This study demonstrated that, in usual clinical practice, switching patients from olanzapine SOT to olanzapine ODT treatment resulted in significant weight loss that was maintained over 12 months. 2008 John Wiley & Sons, Ltd.

Cubic anisotropy in (Ga,Mn)As layers: Experiment and theory

NASA Astrophysics Data System (ADS)

Sawicki, M.; Proselkov, O.; Sliwa, C.; Aleshkevych, P.; Domagala, J. Z.; Sadowski, J.; Dietl, T.

2018-05-01

Historically, comprehensive studies of dilute ferromagnetic semiconductors, e.g., p -type (Cd,Mn)Te and (Ga,Mn)As, paved the way for a quantitative theoretical description of effects associated with spin-orbit interactions in solids, such as crystalline magnetic anisotropy. In particular, the theory was successful in explaining uniaxial magnetic anisotropies associated with biaxial strain and nonrandom formation of magnetic dimers in epitaxial (Ga,Mn)As layers. However, the situation appears much less settled in the case of the cubic term: the theory predicts switchings of the easy axis between in-plane <100 > and <110 > directions as a function of the hole concentration, whereas only the <100 > orientation has been found experimentally. Here, we report on the observation of such switchings by magnetization and ferromagnetic resonance studies on a series of high-crystalline quality (Ga,Mn)As films. We describe our findings by the mean-field p -d Zener model augmented with three new ingredients. The first one is a scattering broadening of the hole density of states, which reduces significantly the amplitude of the alternating carrier-induced contribution. This opens the way for the two other ingredients, namely the so-far disregarded single-ion magnetic anisotropy and disorder-driven nonuniformities of the carrier density, both favoring the <100 > direction of the apparent easy axis. However, according to our results, when the disorder gets reduced, a switching to the <110 > orientation is possible in a certain temperature and hole concentration range.

Perceptual and Conceptual Priming of Cue Encoding in Task Switching

ERIC Educational Resources Information Center

Schneider, Darryl W.

2016-01-01

Transition effects in task-cuing experiments can be partitioned into task switching and cue repetition effects by using multiple cues per task. In the present study, the author shows that cue repetition effects can be partitioned into perceptual and conceptual priming effects. In 2 experiments, letters or numbers in their uppercase/lowercase or…

Modality Switching Cost during Property Verification by 7 Years of Age

ERIC Educational Resources Information Center

Ambrosi, Solene; Kalenine, Solene; Blaye, Agnes; Bonthoux, Francoise

2011-01-01

Recent studies in neuroimagery and cognitive psychology support the view of sensory-motor based knowledge: when processing an object concept, neural systems would re-enact previous experiences with this object. In this experiment, a conceptual switching cost paradigm derived from Pecher, Zeelenberg, and Barsalou (2003, 2004) was used to…

Ultra-low-noise preamplifier for condenser microphones.

PubMed

Starecki, Tomasz

2010-12-01

The paper presents the design of a low-noise preamplifier dedicated for condenser measurement microphones used in high sensitivity applications, in which amplifier noise is the main factor limiting sensitivity of the measurements. In measurement microphone preamplifiers, the dominant source of noise at lower frequencies is the bias resistance of the input stage. In the presented solution, resistors were connected to the input stage by means of switches. The switches are opened during measurements, which disconnects the resistors from the input stage and results in noise reduction. Closing the switches allows for fast charging of the microphone capacitance. At low frequencies the noise of the designed preamplifier is a few times lower in comparison to similar, commercially available instruments.

Investigation of Structures of Microwave Microelectromechanical-System Switches by Taguchi Method

NASA Astrophysics Data System (ADS)

Lai, Yeong-Lin; Lin, Chien-Hung

2007-10-01

The optimal design of microwave microelectromechanical-system (MEMS) switches by the Taguchi method is presented. The structures of the switches are analyzed and optimized in terms of the effective stiffness constant, the maximum von Mises stress, and the natural frequency in order to improve the reliability and the performance of the MEMS switches. There are four factors, each of which has three levels in the Taguchi method for the MEMS switches. An L9(34) orthogonal array is used for the matrix experiments. The characteristics of the experiments are studied by the finite-element method and the analytical method. The responses of the signal-to-noise (S/N) ratios of the characteristics of the switches are investigated. The statistical analysis of variance (ANOVA) is used to interpret the experimental results and decide the significant factors. The final optimum setting, A1B3C1D2, predicts that the effective stiffness constant is 1.06 N/m, the maximum von Mises stress is 76.9 MPa, and the natural frequency is 29.331 kHz. The corresponding switching time is 34 μs, and the pull-down voltage is 9.8 V.

MD simulations of ligand-bound and ligand-free aptamer: molecular level insights into the binding and switching mechanism of the add A-riboswitch.

PubMed

Sharma, Monika; Bulusu, Gopalakrishnan; Mitra, Abhijit

2009-09-01

Riboswitches are structural cis-acting genetic regulatory elements in 5' UTRs of mRNAs, consisting of an aptamer domain that regulates the behavior of an expression platform in response to its recognition of, and binding to, specific ligands. While our understanding of the ligand-bound structure of the aptamer domain of the adenine riboswitches is based on crystal structure data and is well characterized, understanding of the structure and dynamics of the ligand-free aptamer is limited to indirect inferences from physicochemical probing experiments. Here we report the results of 15-nsec-long explicit-solvent molecular dynamics simulations of the add A-riboswitch crystal structure (1Y26), both in the adenine-bound (CLOSED) state and in the adenine-free (OPEN) state. Root-mean-square deviation, root-mean-square fluctuation, dynamic cross-correlation, and backbone torsion angle analyses are carried out on the two trajectories. These, along with solvent accessible surface area analysis of the two average structures, are benchmarked against available experimental data and are shown to constitute the basis for obtaining reliable insights into the molecular level details of the binding and switching mechanism. Our analysis reveals the interaction network responsible for, and conformational changes associated with, the communication between the binding pocket and the expression platform. It further highlights the significance of a, hitherto unreported, noncanonical W:H trans base pairing between A73 and A24, in the OPEN state, and also helps us to propose a possibly crucial role of U51 in the context of ligand binding and ligand discrimination.

Simulation study of a new inverse-pinch high Coulomb transfer switch

NASA Technical Reports Server (NTRS)

Choi, S. H.

1984-01-01

A simulation study of a simplified model of a high coulomb transfer switch is performed. The switch operates in an inverse pinch geometry formed by an all metal chamber, which greatly reduces hot spot formations on the electrode surfaces. Advantages of the switch over the conventional switches are longer useful life, higher current capability and lower inductance, which improves the characteristics required for a high repetition rate switch. The simulation determines the design parameters by analytical computations and comparison with the experimentally measured risetime, current handling capability, electrode damage, and hold-off voltages. The parameters of initial switch design can be determined for the anticipated switch performance. Results are in agreement with the experiment results. Although the model is simplified, the switch characteristics such as risetime, current handling capability, electrode damages, and hold-off voltages are accurately determined.

Implementing Material Surfaces with an Adhesive Switch

DTIC Science & Technology

2014-02-28

squares), M15 (solid triangles), M13 (open circles), M11 (solid circles), or NC14 (open triangles) DNA primary targets. Error bars indicating...5’–ATCAGGCGCAA–3’ M13 = 5’–ATCAGCGGCAATC–3’ M15 = 5’–ATCAGCCCCAATCCA–3’ L3M9 = 5’–ATLCACLCCGLC–3’ L3M11 = 5

Bandwidth Management in Resource Constrained Networks

DTIC Science & Technology

2012-03-01

Postgraduate School OSI Open Systems Interconnection QoS Quality of Service TCP Transmission Control Protocol/Internet Protocol TCP/IP Transmission...filtering. B. NORMAL TCP/IP COMMUNICATIONS The Internet is a “complex network WAN that connects LANs and clients around the globe” (Dean, 2009...of the Open Systems Interconnection ( OSI ) model allowing them to route traffic based on MAC address (Kurose & Ross, 2009). While switching

The Role of Task-Related Learned Representations in Explaining Asymmetries in Task Switching

PubMed Central

Barutchu, Ayla; Becker, Stefanie I.; Carter, Olivia; Hester, Robert; Levy, Neil L.

2013-01-01

Task switch costs often show an asymmetry, with switch costs being larger when switching from a difficult task to an easier task. This asymmetry has been explained by difficult tasks being represented more strongly and consequently requiring more inhibition prior to switching to the easier task. The present study shows that switch cost asymmetries observed in arithmetic tasks (addition vs. subtraction) do not depend on task difficulty: Switch costs of similar magnitudes were obtained when participants were presented with unsolvable pseudo-equations that did not differ in task difficulty. Further experiments showed that neither task switch costs nor switch cost asymmetries were due to perceptual factors (e.g., perceptual priming effects). These findings suggest that asymmetrical switch costs can be brought about by the association of some tasks with greater difficulty than others. Moreover, the finding that asymmetrical switch costs were observed (1) in the absence of a task switch proper and (2) without differences in task difficulty, suggests that present theories of task switch costs and switch cost asymmetries are in important ways incomplete and need to be modified. PMID:23613919

Regression of nifedipine-induced gingival hyperplasia following switch to a same class calcium channel blocker, isradipine.

PubMed

Westbrook, P; Bednarczyk, E M; Carlson, M; Sheehan, H; Bissada, N F

1997-07-01

Patients with nifedipine-induced gingival hyperplasia (GH) often require continued calcium channel blocker therapy. Switches to diltiazem and verapamil have been described; however, these drugs are of a different chemical class and present therapeutic limitations in some patients. The purpose of this study was to evaluate the effect on nifedipine-induced GH of a switch to a dihydropyridine derivative with a low incidence of GH. Fourteen patients with nifedipine-induced GH were given a medical exam and a periodontal exam. The following parameters were assessed: probing depth (PD), gingival margin (GM), gingival thickness (GT), plaque index (PI), and gingival index (GI). Intraoral photographs, study models, and a gingival biopsy for histological examination were taken. Following baseline measures, patients were randomized to continued treatment with nifedipine or an equivalent dose of isradipine in a single-blind fashion. Biweekly periodontal parameters were taken for 8 weeks. At the end of 8 weeks, some patients elected to receive 4 weeks of open label isradipine therapy, with biweekly examination continuing through the open label phase. The isradipine treatment arm showed a mean decrease in PD of 0.59 mm at week 8 (P < 0.05). No other measured parameter (GM, GT, PI, GI) was significantly changed, compared either to baseline or to the alternate treatment arm. Clinically, 60% of patients treated with isradipine exhibited a decrease in hyperplasia, while 66% of patients treated with nifedipine demonstrated an increase in hyperplasia, a significant difference (P < 0.05). When combined with open label data, patients switching therapy to isradipine exhibited an increase in GM (increase in recession) of 0.74 mm from baseline to week 12 (P < 0.05). No patients treated with isradipine exhibited an increase in gingival overgrowth. All patients exhibited adequate control of hypertension. We conclude that in hypertensive patients with nifedipine-induced GH, switching hypertensive therapy to isradipine may result in a regression of GH. When coupled with aggressive oral hygiene treatment, this drug may provide a reasonable option for patients requiring dihydropyridine treatment.

Micro rectennas: Brownian ratchets for thermal-energy harvesting

NASA Astrophysics Data System (ADS)

Pan, Y.; Powell, C. V.; Song, A. M.; Balocco, C.

2014-12-01

We experimentally demonstrated the operation of a rectenna for harvesting thermal (blackbody) radiation and converting it into dc electric power. The device integrates an ultrafast rectifier, the self-switching nanodiode, with a wideband log-periodic spiral microantenna. The radiation from the thermal source drives the rectenna out of thermal equilibrium, permitting the rectification of the excess thermal fluctuations from the antenna. The power conversion efficiency increases with the source temperatures up to 0.02% at 973 K. The low efficiency is attributed mainly to the impedance mismatch between antenna and rectifier, and partially to the large field of view of the antenna. Our device not only opens a potential solution for harvesting thermal energy but also provides a platform for experimenting with Brownian ratchets.

Fast discharge in a plasma gun with hemispherical insulator

NASA Astrophysics Data System (ADS)

Antsiferov, P. S.; Dorokhin, L. A.; Sidelnikov, Yu. V.; Koshelev, K. N.

2009-05-01

A method of creation of hot dense plasma is proposed. It is based on cumulation of a shockwave, which originates on a hemispherical surface of insulator of plasma gun. The results of first experiments are presented. The shock wave is driven by fast electrical discharge (dI /dt>1012 A/s). The inductive storage with semiconductor opening switch is used as a current driver. Time resolved pin-hole images and vacuum ultraviolet (vuv) spectra are studied. Shockwaves from hemispherical insulator with 4 mm radius create plasma with a form of column about 1 mm diameter and 3-4 mm length. vuv spectra contain the lines of Ar ions that corresponds to the electron temperature about 20 eV. Possible practical application is discussed.

The SRS (Segmented Rail Surface) railgun: A new approach to restrike control. [Segmented rail surface

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parker J.V.

1988-01-01

A Segmented Rail Surface (SRS) structure is described that eliminates restrike arcs by progressively disconnecting segments of the rail surface after the plasma armature has passed. This technique has been demonstrated using the Los Alamos MIDI-2 railgun. Restrike was eliminated in a plasma armature acceleration experiment using metal-foil fuses as opening switches. A plasma velocity increase from 11 to 16 km/s was demonstrated using the SRS technique to eliminate the viscous drag losses associated with the restrike plasma. This technique appears to be a practical option for a laboratory launcher at present and for future multi-shot launchers if appropriate switchesmore » can be developed. 5 refs., 8 figs.« less

Quantum Zeno Blockade for Next Generation Optical Switching in Fiber Systems

DTIC Science & Technology

2013-09-01

and utilized a self - referential quantum process tomography method to observe the Zeno effect in optical fiber using the ultrafast all- optical switch...controllable and can be used as a knob to study the core physics behind the Zeno-based switching. For this experiment, we developed a self - referential ...efficient optical communications. The quantum Zeno effect can be used to induce or inhibit optical switching through a variety of processes , all of

Incorrect predictions reduce switch costs.

PubMed

Kleinsorge, Thomas; Scheil, Juliane

2015-07-01

In three experiments, we combined two sources of conflict within a modified task-switching procedure. The first source of conflict was the one inherent in any task switching situation, namely the conflict between a task set activated by the recent performance of another task and the task set needed to perform the actually relevant task. The second source of conflict was induced by requiring participants to guess aspects of the upcoming task (Exps. 1 & 2: task identity; Exp. 3: position of task precue). In case of an incorrect guess, a conflict accrues between the representation of the guessed task and the actually relevant task. In Experiments 1 and 2, incorrect guesses led to an overall increase of reaction times and error rates, but they reduced task switch costs compared to conditions in which participants predicted the correct task. In Experiment 3, incorrect guesses resulted in faster performance overall and to a selective decrease of reaction times in task switch trials when the cue-target interval was long. We interpret these findings in terms of an enhanced level of controlled processing induced by a combination of two sources of conflict converging upon the same target of cognitive control. Copyright © 2015 Elsevier B.V. All rights reserved.

Morphological Priming Survives a Language Switch

ERIC Educational Resources Information Center

Verdonschot, Rinus G.; Middelburg, Renee; Lensink, Saskia E.; Schiller, Niels O.

2012-01-01

In a long-lag morphological priming experiment, Dutch (L1)-English (L2) bilinguals were asked to name pictures and read aloud words. A design using non-switch blocks, consisting solely of Dutch stimuli, and switch-blocks, consisting of Dutch primes and targets with intervening English trials, was administered. Target picture naming was facilitated…

A Comparison of the AC Breakdown Strength of New and Used Poly A-Olefin Oil to Transformer Oil (Preprint)

DTIC Science & Technology

2006-04-01

high- pressure switch program at the University of Missouri - Columbia is presently utilizing synthetic dielectric oil as the switching medium [I...power supplies, and ordinance systems. The temperature of the PA0 utilized in the high- pressure switch program routinely experiences thermal

Still Clever after All These Years: Searching for the Homunculus in Explicitly Cued Task Switching

ERIC Educational Resources Information Center

Logan, Gordon D.; Schneider, Darryl W.; Bundesen, Claus

2007-01-01

Many researchers interpret switch costs in the explicit task-cuing procedure as reflecting endogenous task-set reconfiguration. G. D. Logan and C. Bundesen (2003) challenged this interpretation empirically and theoretically. They argued that many experiments confounded cue encoding benefits with switch costs and they showed that unconfounded…

STABLE ISOTOPE SIGNATURES OF MUCUS OF STEELHEAD TROUT IN A CONTROLLED DIET SWITCH EXPERIMENT

EPA Science Inventory

Our work has shown that fish mucus can serve as a very rapid indicator of diet switching in fish. We performed diet switching studies of steelhead trout in a controlled hatchery setting using specially formulated low delta 15N signature and high delta 15N signature diets. To ou...

Compact pulsed high-energy Er:glass laser

NASA Astrophysics Data System (ADS)

Wan, Peng; Liu, Jian

2012-03-01

Bulk Erbium-doped lasers are widely used for long-distance telemetry and ranging. In some applications such as coherent Doppler radars, laser outputs with a relatively long pulse width, good beam profile and pulse shape are required. High energy Q-switched Er:glass lasers were demonstrated by use of electro-optic (E/O) Q-switching or frustrated total internal reflection (FTIR) Q-switching. However, the output pulse durations in these lasers were fixed to relatively small values and extremely hard to tune. We report here on developing a novel and compact Q-switched Er:Yb co-doped phosphate glass laser at an eye-safe wavelength of 1.5 μm. A rotating mirror was used as a Q-switch. Co-linear pump scheme was used to maintain a good output beam profile. Near-perfect Gaussian temporal shape was obtained in our experiment. By changing motor rotation speed, pulse duration was tunable and up to 240 ns was achieved. In our preliminary experiment, output pulse energies of 44 mJ and 4.5 mJ were obtained in free-running and Q-switched operation modes respectively.

Evolutionary replacement of UV vision by violet vision in fish.

PubMed

Tada, Takashi; Altun, Ahmet; Yokoyama, Shozo

2009-10-13

The vertebrate ancestor possessed ultraviolet (UV) vision and many species have retained it during evolution. Many other species switched to violet vision and, then again, some avian species switched back to UV vision. These UV and violet vision are mediated by short wavelength-sensitive (SWS1) pigments that absorb light maximally (lambda(max)) at approximately 360 and 390-440 nm, respectively. It is not well understood why and how these functional changes have occurred. Here, we cloned the pigment of scabbardfish (Lepidopus fitchi) with a lambda(max) of 423 nm, an example of violet-sensitive SWS1 pigment in fish. Mutagenesis experiments and quantum mechanical/molecular mechanical (QM/MM) computations show that the violet-sensitivity was achieved by the deletion of Phe-86 that converted the unprotonated Schiff base-linked 11-cis-retinal to a protonated form. The finding of a violet-sensitive SWS1 pigment in scabbardfish suggests that many other fish also have orthologous violet pigments. The isolation and comparison of such violet and UV pigments in fish living in different ecological habitats will open an unprecedented opportunity to elucidate not only the molecular basis of phenotypic adaptations, but also the genetics of UV and violet vision.

Prevention of venous pain and phlebitis caused by epirubicin hydrochloride.

PubMed

Sugimoto, Masakazu; Matsui, Masateru; Harada, Masanori; Yamauchi, Yumiko; Moriyama, Nao; Andou, Kanae; Yamamoto, Makoto; Yamaoka, Hisayo; Ono, Chiemi; Ishikawa, Mami; Kamo, Nobuyuki; Ikeda, Tadashi; Yamaoka, Keiko

2009-06-01

Many patients complain of venous pain or develop phlebitis following treatment with epirubicin hydrochloride(EPI). To ensure effective and safe treatment with this drug, it is essential to deal with the adverse events associated with it appropriately. At our hospital, EPI was previously administered by drip infusion(diluted with 50mL of physiological saline)over 15 minutes after pretreatment(EPI main route). With this method of treatment, venous pain and phlebitis developed in 14 of 15 cases. In 3 of these 14 cases, the regimen was modified. Following this experience, EPI administration was switched to drip infusion from the fully-opened side tube used for pretreatment(EPI sub-route). Switching to this route resulted in a sharp decrease in the incidence of venous pain and phlebitis, to only 1 of 15 cases. Stimulation of vascular tunica intima by EPI has been considered a factor principally responsible for the venous pain and phlebitis seen after EPI therapy. To prevent these adverse reactions, it is necessary to modify the method of administration so that strong or long-term exposure of blood vessels to EPI can be reduced. The results of this study suggest that the EPI sub-route we devised is useful in achieving this goal.

Comparing the Effectiveness and Safety of the Addition of and Switching to Aripiprazole for Resolving Antipsychotic-Induced Hyperprolactinemia: A Multicenter, Open-Label, Prospective Study.

PubMed

Yoon, Hui Woo; Lee, Jung Suk; Park, Sang Jin; Lee, Seon-Koo; Choi, Won-Jung; Kim, Tae Yong; Hong, Chang Hyung; Seok, Jeong-Ho; Park, Il-Ho; Son, Sang Joon; Roh, Daeyoung; Kim, Bo-Ra; Lee, Byung Ook

Hyperprolactinemia is an important but often overlooked adverse effect of antipsychotics. Several studies have shown that switching to or adding aripiprazole normalizes antipsychotic-induced hyperprolactinemia. However, no study has directly compared the effectiveness and safety of the 2 strategies. A total of 52 patients with antipsychotic-induced hyperprolactinemia were recruited. Aripiprazole was administered to patients with mild hyperprolactinemia (serum prolactin level < 50 ng/mL). Patients with severe hyperprolactinemia (serum prolactin level > 50 ng/mL) were randomized to an aripiprazole-addition group (adding aripiprazole to previous antipsychotics) or a switching group (switching previous antipsychotics to aripiprazole). Serum prolactin level, menstrual disturbances, sexual dysfunction, psychopathologies, and quality of life were measured at weeks 0, 1, 2, 4, 6, and 8. Both the addition and switching groups showed significantly reduced serum prolactin level and menstrual disturbances and improved sexual dysfunction. In patients with severe hyperprolactinemia, the numbers of patients with hyperprolactinemia and menstrual disturbance in the switching group were significantly lower than those in the addition group at week 8. Both the addition and switching strategies were effective in resolving antipsychotic-induced hyperprolactinemia and hyperprolactinemia-related adverse events, including menstrual disturbances and sexual dysfunction. In addition, these findings suggest that switching to aripiprazole may be more effective than addition of aripiprazole for normalizing hyperprolactinemia and improving hyperprolactinemia-related adverse events in patients with schizophrenia.

Improvement of Diurnal Blood Pressure Variation by Azilsartan

PubMed Central

Okamura, Keisuke; Shirai, Kazuyuki; Okuda, Tetsu; Urata, Hidenori

2018-01-01

Background Azilsartan is an angiotensin II receptor blocker with a potent antihypertensive effect. Methods In a multicenter, prospective, open-label study, 265 patients with poor blood pressure control despite treatment with other angiotensin II receptor blockers were switched to 20 mg/day of azilsartan (patients on standard dosages) or 40 mg/day of azilsartan (patients on high dosages). Results Blood pressure was 149/83 mm Hg before switching and was significantly reduced from 1 month after switching until final assessment (132/76 mm Hg, P < 0.001). The pulse rate was 72/min before switching and increased significantly from 3 months after switching until final assessment (74/min, P < 0.005). A significant decrease of home morning systolic and diastolic pressure was observed from 1 and 3 months, respectively. Home morning blood pressure was 143/82 mm Hg before switching and 130/76 mm Hg at final assessment (P < 0.01). The morning-evening difference of systolic blood pressure decreased from 14.6 to 6.6 mm Hg after switching (P = 0.09). The estimated glomerular filtration rate was significantly decreased at 3, 6, and 12 months after switching, and serum uric acid was significantly increased at 12 months. No serious adverse events occurred. Conclusion Azilsartan significantly reduced the blood pressure and decreased diurnal variation in patients responding poorly to other angiotensin II receptor blockers. PMID:29238433

Fuel Delivery System.

DTIC Science & Technology

1996-07-24

to fuel tank 27 aboard 23 test torpedo 26. Pressure switch 19B operates to close solenoid 24 valve 22A and concurrently open solenoid valve 22D...leading to a pump explosion. The boost pump 4 is driven by its 11 motor 14B and positive displacement pump 1 by its respective 12 motor 14A. Pressure ... switch 19A monitors the head pressure 13 created by the boost pump 4 and it will shut off the motor 14A of 14 the positive displacement pump 1 if

Generator powered electrically heated diesel particulate filter

DOEpatents

Gonze, Eugene V; Paratore, Jr., Michael J

2014-03-18

A control circuit for a vehicle powertrain includes a switch that selectivity interrupts current flow between a first terminal and a second terminal. A first power source provides power to the first terminal and a second power source provides power to the second terminal and to a heater of a heated diesel particulate filter (DPF). The switch is opened during a DPF regeneration cycle to prevent the first power source from being loaded by the heater while the heater is energized.

Megawatt level UV output from [110] Cr⁴⁺:YAG passively Q-switched microchip laser.

PubMed

Bhandari, Rakesh; Taira, Takunori

2011-11-07

Recent development of megawatt peak power, giant pulse microchip lasers has opened new opportunities for efficient wavelength conversion, provided the output of the microchip laser is linearly polarized. We obtain > 2 MW peak power, 260 ps, 100 Hz pulses at 266 nm by fourth harmonic conversion of a linearly polarized Nd:YAG microchip laser that is passively Q-switched with [110] cut Cr⁴⁺:YAG. The SHG and FHG conversion efficiencies are 85% and 51%, respectively.

Coformulated bictegravir, Emtricitabine (F), tenofovir alafenamide (TAF) after initial treatment with bictegravir or dolutegravir plus F/TAF.

PubMed

Sax, Paul E; Dejesus, Edwin; Crofoot, Gordon; Ward, Douglas; Benson, Paul; Dretler, Robin; Mills, Anthony; Brinson, Cynthia; Wei, Xuelian; Collins, Sean E; Cheng, Andrew

2018-05-22

: A phase 2, randomized, active-controlled study of initial antiretroviral therapy with bictegravir or dolutegravir in combination with emtricitabine and tenofovir alafenamide showed excellent efficacy. After 60 weeks of blinded treatment, participants switched to a single tablet regimen of bictegravir, emtricitabine and tenofovir alafenamide. Switching maintained viral suppression in all participants who chose to remain on the study through at least 12 weeks in the open-label phase, was safe and well tolerated.

The Muslim Headscarf and Face Perception: “They All Look the Same, Don't They?”

PubMed Central

Toseeb, Umar; Bryant, Eleanor J.; Keeble, David R. T.

2014-01-01

The headscarf conceals hair and other external features of a head (such as the ears). It therefore may have implications for the way in which such faces are perceived. Images of faces with hair (H) or alternatively, covered by a headscarf (HS) were used in three experiments. In Experiment 1 participants saw both H and HS faces in a yes/no recognition task in which the external features either remained the same between learning and test (Same) or switched (Switch). Performance was similar for H and HS faces in both the Same and Switch condition, but in the Switch condition it dropped substantially compared to the Same condition. This implies that the mere presence of the headscarf does not reduce performance, rather, the change between the type of external feature (hair or headscarf) causes the drop in performance. In Experiment 2, which used eye-tracking methodology, it was found that almost all fixations were to internal regions, and that there was no difference in the proportion of fixations to external features between the Same and Switch conditions, implying that the headscarf influenced processing by virtue of extrafoveal viewing. In Experiment 3, similarity ratings of the internal features of pairs of HS faces were higher than pairs of H faces, confirming that the internal and external features of a face are perceived as a whole rather than as separate components. PMID:24520313

Design and Development of a Series Switch for High Voltage in RF Heating

NASA Astrophysics Data System (ADS)

Patel, Himanshu K.; Shah, Deep; Thacker, Mauli; Shah, Atman

2013-02-01

Plasma is the fourth state of matter. To sustain plasma in its ionic form very high temperature is essential. RF heating systems are used to provide the required temperature. Arching phenomenon in these systems can cause enormous damage to the RF tube. Heavy current flows across the anode-cathode junction, which need to be suppressed in minimal time for its protection. Fast-switching circuit breakers are used to cut-off the load from the supply in cases of arching. The crowbar interrupts the connection between the high voltage power supply (HVPS) and the RF tube for a temporary period between which the series switch has to open. The crowbar shunts the current across the load but in the process leads to short circuiting the HVPS. Thus, to protect the load as well as the HVPS a series switch is necessary. This paper presents the design and development of high voltage Series Switch for the high power switching applications. Fiber optic based Optimum triggering scheme is designed and tested to restrict the time delay well within the stipulated limits. The design is well supported with the experimental results for the whole set-up along with the series switch at various voltage level before its approval for operation at 5.2 kV.

Evaluation of Biomarkers of Exposure in Smokers Switching to a Carbon-Heated Tobacco Product: A Controlled, Randomized, Open-Label 5-Day Exposure Study

PubMed Central

Haziza, Christelle; Weitkunat, Rolf; Magnette, John

2016-01-01

Introduction: Tobacco harm reduction aims to provide reduced risk alternatives to adult smokers who would otherwise continue smoking combustible cigarettes (CCs). This randomized, open-label, three-arm, parallel-group, single-center, short-term confinement study aimed to investigate the effects of exposure to selected harmful and potentially harmful constituents (HPHCs) of cigarette smoke in adult smokers who switched to a carbon-heated tobacco product (CHTP) compared with adult smokers who continued to smoke CCs and those who abstained from smoking for 5 days. Methods: Biomarkers of exposure to HPHCs, including nicotine and urinary excretion of mutagenic material, were measured in 24-hour urine and blood samples in 112 male and female Caucasian smokers switching from CCs to the CHTP ad libitum use. Puffing topography was assessed during product use. Results: Switching to the CHTP or smoking abstinence (SA) resulted in marked decreases from baseline to Day 5 in all biomarkers of exposure measured, including carboxyhemoglobin (43% and 55% decrease in the CHTP and SA groups, respectively). The urinary excretion of mutagenic material was also markedly decreased on Day 5 compared with baseline (89% and 87% decrease in the CHTP and SA groups, respectively). No changes in biomarkers of exposure to HPHCs or urinary mutagenic material were observed between baseline and Day 5 in the CC group. Conclusions: Our results provide clear evidence supporting a reduction in the level of exposure to HPHCs of tobacco smoke in smokers who switch to CHTP under controlled conditions, similar to that observed in SA. Implications: The reductions observed in biomarkers of exposure to HPHCs of tobacco smoke in this short-term study could potentially also reduce the incidence of cancer, cardiovascular and respiratory diseases in those smokers who switch to a heated tobacco product. PMID:26817490

Left Ventricular Retraining and Late Arterial Switch for D-Transposition of the Great Arteries.

PubMed

Watanabe, Naruhito; Mainwaring, Richard D; Carrillo, Sergio A; Lui, George K; Reddy, V Mohan; Hanley, Frank L

2015-05-01

For many decades, patients with d-transposition of the great arteries underwent an atrial switch procedure. Although many of these patients have continued to do well, a subset experience profound right ventricular failure. Some may be candidates for left ventricular (LV) retraining and late arterial switch. The purpose of this study was to review our experience with LV retraining and late arterial switch. This was a retrospective review of 32 patients with d-transposition. Thirty patients underwent a previous atrial switch and subsequently experienced right ventricular failure, whereas 2 presented late (8 months and 6 years) without previous intervention. The median age at the time of enrollment in this program was 15 years. Seven patients proceeded directly to late arterial switch owing to systemic LV pressures. The remaining 25 underwent a pulmonary artery band for LV retraining. Twenty of the 32 (63%) patients enrolled in this program were able to undergo a late arterial switch. There were 2 operative mortalities (10%). Two additional patients survived surgery but died in the early outpatient time period. There has been no late mortality after the arterial switch with a median follow-up of 5 years. Twelve patients underwent one or more pulmonary artery band procedures without evidence of effective LV retraining. There have been 2 early and 3 late (42%) deaths in this subgroup. The outcomes after arterial switch are encouraging and suggest that LV retraining and late arterial switch provide a viable option for this complex group of patients. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

UV/vis and NIR light-responsive spiropyran self-assembled monolayers.

PubMed

Ivashenko, Oleksii; van Herpt, Jochem T; Feringa, Ben L; Rudolf, Petra; Browne, Wesley R

2013-04-02

Self-assembled monolayers of a 6-nitro BIPS spiropyran (SP) modified with a disulfide-terminated aliphatic chain were prepared on polycrystalline gold surfaces and characterized by UV/vis absorption, surface-enhanced Raman scattering (SERS), and X-ray photoelectron spectroscopies (XPS). The SAMs obtained are composed of the ring-closed form (i.e., spiropyran) only. Irradiation with UV light results in conversion of the monolayer to the merocyanine form (MC), manifested in the appearance of an N(+) contribution in the N 1s region of the XPS spectrum of the SAMs, the characteristic absorption band of the MC form in the visible region at 555 nm, and the C-O stretching band in the SERS spectrum. Recovery of the initial state of the monolayer was observed both thermally and after irradiation with visible light. Several switching cycles were performed and monitored by SERS spectroscopy, demonstrating the stability of the SAMs during repeated switching between SP and MC states. A key finding in the present study is that ring-opening of the surface-immobilized spiropyrans can be induced by irradiation with continuous wave NIR (785 nm) light as well as by irradiation with UV light. We demonstrate that ring-opening by irradiation at 785 nm proceeds by a two-photon absorption pathway both in the SAMs and in the solid state. Hence, spiropyran SAMs on gold can undergo reversible photochemical switching from the SP to the MC form with both UV and NIR and the reverse reaction induced by irradiation with visible light or heating. Furthermore, the observation of NIR-induced switching with a continuous wave source holds important consequences in the study of photochromic switches on surfaces using SERS and emphasizes the importance of the use of multiple complementary techniques in characterizing photoresponsive SAMs.

The role of semantic processing in reading Japanese orthographies: an investigation using a script-switch paradigm.

PubMed

Dylman, Alexandra S; Kikutani, Mariko

2018-01-01

Research on Japanese reading has generally indicated that processing of the logographic script Kanji primarily involves whole-word lexical processing and follows a semantics-to-phonology route, while the two phonological scripts Hiragana and Katakana (collectively called Kana) are processed via a sub-lexical route, and more in a phonology-to-semantics manner. Therefore, switching between the two scripts often involves switching between two reading processes, which results in a delayed response for the second script (a script switch cost). In the present study, participants responded to pairs of words that were written either in the same orthography (within-script), or in two different Japanese orthographies (cross-script), switching either between Kanji and Hiragana, or between Katakana and Hiragana. They were asked to read the words aloud (Experiments 1 and 3) and to make a semantic decision about them (Experiments 2 and 4). In contrast to initial predictions, a clear switch cost was observed when participants switched between the two Kana scripts, while script switch costs were less consistent when participants switched between Kanji and Hiragana. This indicates that there are distinct processes involved in reading of the two types of Kana, where Hiragana reading appears to bear some similarities to Kanji processing. This suggests that the role of semantic processing in Hiragana (but not Katakana) reading is more prominent than previously thought and thus, Hiragana is not likely to be processed strictly phonologically.

SESOTHO trial ("Switch Either near Suppression Or THOusand") - switch to second-line versus WHO-guided standard of care for unsuppressed patients on first-line ART with viremia below 1000 copies/mL: protocol of a multicenter, parallel-group, open-label, randomized clinical trial in Lesotho, Southern Africa.

PubMed

Amstutz, Alain; Nsakala, Bienvenu Lengo; Vanobberghen, Fiona; Muhairwe, Josephine; Glass, Tracy Renée; Achieng, Beatrice; Sepeka, Mamorena; Tlali, Katleho; Sao, Lebohang; Thin, Kyaw; Klimkait, Thomas; Battegay, Manuel; Labhardt, Niklaus Daniel

2018-02-12

The World Health Organization (WHO) recommends viral load (VL) measurement as the preferred monitoring strategy for HIV-infected individuals on antiretroviral therapy (ART) in resource-limited settings. The new WHO guidelines 2016 continue to define virologic failure as two consecutive VL ≥1000 copies/mL (at least 3 months apart) despite good adherence, triggering switch to second-line therapy. However, the threshold of 1000 copies/mL for defining virologic failure is based on low-quality evidence. Observational studies have shown that individuals with low-level viremia (measurable but below 1000 copies/mL) are at increased risk for accumulation of resistance mutations and subsequent virologic failure. The SESOTHO trial assesses a lower threshold for switch to second-line ART in patients with sustained unsuppressed VL. In this multicenter, parallel-group, open-label, randomized controlled trial conducted in Lesotho, patients on first-line ART with two consecutive unsuppressed VL measurements ≥100 copies/mL, where the second VL is between 100 and 999 copies/mL, will either be switched to second-line ART immediately (intervention group) or not be switched (standard of care, according to WHO guidelines). The primary endpoint is viral resuppression (VL < 50 copies/mL) 9 months after randomization. We will enrol 80 patients, giving us 90% power to detect a difference of 35% in viral resuppression between the groups (assuming two-sided 5% alpha error). For our primary analysis, we will use a modified intention-to-treat set, with those lost to care, death, or crossed over considered failure to resuppress, and using logistic regression models adjusted for the prespecified stratification variables. The SESOTHO trial challenges the current WHO guidelines, assessing an alternative, lower VL threshold for patients with unsuppressed VL on first-line ART. This trial will provide data to inform future WHO guidelines on VL thresholds to recommend switch to second-line ART. ClinicalTrials.gov ( NCT03088241 ), registered May 05, 2017.

Dynamics in hybrid complex systems of switches and oscillators

NASA Astrophysics Data System (ADS)

Taylor, Dane; Fertig, Elana J.; Restrepo, Juan G.

2013-09-01

While considerable progress has been made in the analysis of large systems containing a single type of coupled dynamical component (e.g., coupled oscillators or coupled switches), systems containing diverse components (e.g., both oscillators and switches) have received much less attention. We analyze large, hybrid systems of interconnected Kuramoto oscillators and Hopfield switches with positive feedback. In this system, oscillator synchronization promotes switches to turn on. In turn, when switches turn on, they enhance the synchrony of the oscillators to which they are coupled. Depending on the choice of parameters, we find theoretically coexisting stable solutions with either (i) incoherent oscillators and all switches permanently off, (ii) synchronized oscillators and all switches permanently on, or (iii) synchronized oscillators and switches that periodically alternate between the on and off states. Numerical experiments confirm these predictions. We discuss how transitions between these steady state solutions can be onset deterministically through dynamic bifurcations or spontaneously due to finite-size fluctuations.

A single-stage optical load-balanced switch for data centers.

PubMed

Huang, Qirui; Yeo, Yong-Kee; Zhou, Luying

2012-10-22

Load balancing is an attractive technique to achieve maximum throughput and optimal resource utilization in large-scale switching systems. However current electronic load-balanced switches suffer from severe problems in implementation cost, power consumption and scaling. To overcome these problems, in this paper we propose a single-stage optical load-balanced switch architecture based on an arrayed waveguide grating router (AWGR) in conjunction with fast tunable lasers. By reuse of the fast tunable lasers, the switch achieves both functions of load balancing and switching through the AWGR. With this architecture, proof-of-concept experiments have been conducted to investigate the feasibility of the optical load-balanced switch and to examine its physical performance. Compared to three-stage load-balanced switches, the reported switch needs only half of optical devices such as tunable lasers and AWGRs, which can provide a cost-effective solution for future data centers.

Conceptual design of a high-speed electromagnetic switch for a modified flux-coupling-type SFCL and its application in renewable energy system.

PubMed

Chen, Lei; Chen, Hongkun; Yang, Jun; Shu, Zhengyu; He, Huiwen; Shu, Xin

2016-01-01

The modified flux-coupling-type superconducting fault current (SFCL) is a high-efficient electrical auxiliary device, whose basic function is to suppress the short-circuit current by controlling the magnetic path through a high-speed switch. In this paper, the high-speed switch is based on electromagnetic repulsion mechanism, and its conceptual design is carried out to promote the application of the modified SFCL. Regarding that the switch which is consisting of a mobile copper disc, two fixed opening and closing coils, the computational method for the electromagnetic force is discussed, and also the dynamic mathematical model including circuit equation, magnetic field equation as well as mechanical motion equation is theoretically deduced. According to the mathematical modeling and calculation of characteristic parameters, a feasible design scheme is presented, and the high-speed switch's response time can be less than 0.5 ms. For that the modified SFCL is equipped with this high-speed switch, the SFCL's application in a 10 kV micro-grid system with multiple renewable energy sources are assessed in the MATLAB software. The simulations are well able to affirm the SFCL's performance behaviors.

46 CFR 169.681 - Disconnect switches and devices.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Machinery and Electrical Electrical Installations Operating at Potentials of 50 Volts Or More on Vessels of... controllers. (e) Disconnect means must be provided to open all conductors of generator and shore power cables...

European Non-Dissipative Bypass Switch For Li-Ion Batteries And Prospective

NASA Astrophysics Data System (ADS)

Pasquier, E.; Castric, AF.; Mosset, E.; Chandeneau, A.

2011-10-01

Li-ion batteries are made of cells or modules connected in series. In case one may be too weak or failed, it becomes necessary to remove it from the serial circuit. This is the by-pass operation which provides overcharge/open-circuitprotection,limitation of possible constraints linked to over- discharge/reversal/"self-short" and avoid to jeopardize rest of battery. One system is particularly adapted to Space Li-ion batteries: the "make before break" Single Pole Double Throw (SPDT) switch which avoids open- circuit on power circuit when correctly activated. This paper presents the component constraints, the development in the frame of ESA Artès 3 program up to its qualification, as well as the motorization approach linked to ECSS-E-30 (mechanical - Part 3: Mechanisms) and future opportunities of such system.

Simplification to single-tablet regimen of elvitegravir, cobicistat, emtricitabine, tenofovir DF from multi-tablet ritonavir-boosted protease inhibitor plus coformulated emtricitabine and tenofovir DF regimens: week 96 results of STRATEGY-PI.

PubMed

Arribas, Jose R; DeJesus, Edwin; van Lunzen, Jan; Zurawski, Christine; Doroana, Manuela; Towner, William; Lazzarin, Adriano; Nelson, Mark; McColl, Damian; Andreatta, Kristen; Swamy, Raji; Szwarcberg, Javier; Nguyen, Thai

2017-05-01

Antiretroviral therapy (ART) simplification to a single-tablet regimen can benefit HIV-1-infected, virologically suppressed, individuals on ART composed of multiple pills. We assessed long-term efficacy and safety of switching to co-formulated elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate (E/C/F/TDF) from multi-tablet ritonavir-boosted protease inhibitor (PI + RTV) plus F/TDF (TVD) regimens. STRATEGY-PI was a 96-week, phase 3b, randomized (2:1), open-label, non-inferiority study examining the efficacy, safety, and tolerability of switching to E/C/F/TDF from PI + RTV + TVD regimens in virologically suppressed individuals (HIV-1 RNA <50 copies/mL). Participants were randomized to switch to E/C/F/TDF (switch group) or to continue their PI + RTV + TVD regimens (no-switch group). Eligibility criteria included no resistance to F/TDF or history of virologic failure, and estimated creatinine clearance ≥70 mL/min. At week 96, 87% (252/290) of switch and 70% (97/139) of no-switch participants maintained HIV-1 RNA <50 copies/mL (difference: 17%, 95% CI 8.7-26.0%, p < 0.001). Superiority of the switch to E/C/F/TDF vs. no-switch was due to a smaller proportion of both virologic failures (switch, 1% [3/290]; no-switch, 6% [8/139]) and discontinuations for non-virologic reasons (switch, 11% [31/290]; no-switch, 24% [33/139]). No treatment-emergent resistance was observed in switch subjects with virologic failure. Discontinuation rates from adverse events were 3% in both groups (9/293, switch; 4/140, no-switch). Switching from PI + RTV + TVD to E/C/F/TDF was associated with significant improvements in patient-reported outcomes related to gastrointestinal symptoms (nausea and bloating). E/C/F/TDF is a safe, effective long-term alternative to multi-tablet PI + RTV + TVD-based regimens in virologically suppressed, HIV-1-infected adults, and improves patient-reported gastrointestinal symptoms.

Worcester 1 Inch Solenoid Actuated Gas Operated SCHe System Valves

DOE Office of Scientific and Technical Information (OSTI.GOV)

MISKA, C.R.

1 inch gas-operated full-port ball valves incorporate a solenoid and limit switches as integral parts of the actuator. These valves are normally open and fail safe to the open position (GOV-1*02 and 1*06 fail closed) to provide a flow path of helium gas to the MCO under helium purge and off-normal conditions when the MCO is isolated.

Worcester 1 Inch Solenoid Actuated Gas Operated SCHe System Valves

DOE Office of Scientific and Technical Information (OSTI.GOV)

VAN KATWIJK, C.

1 inch Gas-operated full-port ball valves incorporate a solenoid and limit switches as integral parts of the actuator. These valves are normally open and fail safe to the open position (GOV-1*02 and 1*06 fall closed) to provide a flow path of helium gas to the MCO under helium purge and off-normal conditions when the MCO is isolated.

Worcester 1 Inch Solenoid Actuated Gas Operated SCHe System Valves

DOE Office of Scientific and Technical Information (OSTI.GOV)

VAN KATWIJK, C.

1 inch Gas-operated full-port ball valves incorporate a solenoid and limit switches as integral parts of the actuator. These valves are normally open and fail safe to the open position (GOV-1*02 and 1*06 fail closed) to provide a flow path of helium gas to the MCO under helium purge and off-normal conditions when the MCO is isolated.

Effect of oxygen concentration on resistive switching behavior in silicon oxynitride film

NASA Astrophysics Data System (ADS)

Chen, Da; Huang, Shihua; He, Lü

2017-04-01

SiO{}xN{}y films with different oxygen concentrations were fabricated by reactive magnetron sputtering, and the resistive switching characteristics and conduction mechanism of Cu/SiO{}xN{}y/ITO devices were investigated. The Cu/SiO{}xN{}y/ITO device with SiO{}xN{}y deposited in 0.8-sccm O{}2 flow shows a reliable resistive switching behavior, including good endurance and retention properties. As the conductivity of SiO{}xN{}y increases with the increase of the oxygen content dynamical electron trapping and detrapping is suggested to be the conduction mechanism. The temperature dependent I-V measurement indicates that the carrier transport can be ascribed to the hopping conduction rather than the metallic conductive filament. Project supported by the Natural Science Foundation of Zhejiang Province (No. LY17F040001), the Open Project Program of Surface Physics Laboratory (National Key Laboratory) of Fudan University (No. KF2015_02), the Open Project Program of National Laboratory for Infrared Physics, Chinese Academy of Sciences (No. M201503), the Zhejiang Provincial Science and Technology Key Innovation Team (No. 2011R50012), and the Zhejiang Provincial Key Laboratory (No. 2013E10022).

Design of automatic curtain controlled by wireless based on single chip 51 microcomputer

NASA Astrophysics Data System (ADS)

Han, Dafeng; Chen, Xiaoning

2017-08-01

In order to realize the wireless control of the domestic intelligent curtains, a set of wireless intelligent curtain control system based on 51 single chip microcomputer have been designed in this paper. The intelligent curtain can work in the manual mode, automatic mode and sleep mode and can be carried out by the button and mobile phone APP mode loop switch. Through the photosensitive resistance module and human pyroelectric infrared sensor to collect the indoor light value and the data whether there is the person in the room, and then after single chip processing, the motor drive module is controlled to realize the positive inversion of the asynchronous motor, the intelligent opening and closing of the curtain have been realized. The operation of the motor can be stopped under the action of the switch and the curtain opening and closing and timing switch can be controlled through the keys and mobile phone APP. The optical fiber intensity, working mode, curtain state and system time are displayed by LCD1602. The system has a high reliability and security under practical testing and with the popularity and development of smart home, the design has broad market prospects.

Resistance change effect in SrTiO3/Si (001) isotype heterojunction

NASA Astrophysics Data System (ADS)

Huang, Xiushi; Gao, Zhaomeng; Li, Pei; Wang, Longfei; Liu, Xiansheng; Zhang, Weifeng; Guo, Haizhong

2018-02-01

Resistance switching has been observed in double and multi-layer structures of ferroelectric films. The higher switching ratio opens up a vast path for emerging ferroelectric semiconductor devices. An n-n+ isotype heterojunction has been fabricated by depositing an oxide SrTiO3 layer on a conventional n-type Si (001) substrate (SrTiO3/Si) by pulsed laser disposition. Rectification and resistive switching behaviors in the n-n+ SrTiO3/Si heterojunction were observed by a conductive atomic force microscopy, and the n-n+ SrTiO3/Si heterojunction exhibits excellent endurance and retention characteristics. The possible mechanism was proposed based on the band structure of the n-n+ SrTiO3/Si heterojunction, and the observed electrical behaviors could be attributed to the modulation effect of the electric field reversal on the width of accumulation and the depletion region, as well as the height of potential of the n-n+ junction formed at the STO/Si interface. Moreover, oxygen vacancies are also indicated to play a crucial role in causing insulator to semiconductor transition. These results open the way to potential application in future microelectronic devices based on perovskite oxide layers on conventional semiconductors.

Building SDN-Based Agricultural Vehicular Sensor Networks Based on Extended Open vSwitch.

PubMed

Huang, Tao; Yan, Siyu; Yang, Fan; Pan, Tian; Liu, Jiang

2016-01-19

Software-defined vehicular sensor networks in agriculture, such as autonomous vehicle navigation based on wireless multi-sensor networks, can lead to more efficient precision agriculture. In SDN-based vehicle sensor networks, the data plane is simplified and becomes more efficient by introducing a centralized controller. However, in a wireless environment, the main controller node may leave the sensor network due to the dynamic topology change or the unstable wireless signal, leaving the rest of network devices without control, e.g., a sensor node as a switch may forward packets according to stale rules until the controller updates the flow table entries. To solve this problem, this paper proposes a novel SDN-based vehicular sensor networks architecture which can minimize the performance penalty of controller connection loss. We achieve this by designing a connection state detection and self-learning mechanism. We build prototypes based on extended Open vSwitch and Ryu. The experimental results show that the recovery time from controller connection loss is under 100 ms and it keeps rule updating in real time with a stable throughput. This architecture enhances the survivability and stability of SDN-based vehicular sensor networks in precision agriculture.

Building SDN-Based Agricultural Vehicular Sensor Networks Based on Extended Open vSwitch

PubMed Central

Huang, Tao; Yan, Siyu; Yang, Fan; Pan, Tian; Liu, Jiang

2016-01-01

Software-defined vehicular sensor networks in agriculture, such as autonomous vehicle navigation based on wireless multi-sensor networks, can lead to more efficient precision agriculture. In SDN-based vehicle sensor networks, the data plane is simplified and becomes more efficient by introducing a centralized controller. However, in a wireless environment, the main controller node may leave the sensor network due to the dynamic topology change or the unstable wireless signal, leaving the rest of network devices without control, e.g., a sensor node as a switch may forward packets according to stale rules until the controller updates the flow table entries. To solve this problem, this paper proposes a novel SDN-based vehicular sensor networks architecture which can minimize the performance penalty of controller connection loss. We achieve this by designing a connection state detection and self-learning mechanism. We build prototypes based on extended Open vSwitch and Ryu. The experimental results show that the recovery time from controller connection loss is under 100 ms and it keeps rule updating in real time with a stable throughput. This architecture enhances the survivability and stability of SDN-based vehicular sensor networks in precision agriculture. PMID:26797616

EOBII Controls Flower Opening by Functioning as a General Transcriptomic Switch1[C][W

PubMed Central

Colquhoun, Thomas A.; Schwieterman, Michael L.; Wedde, Ashlyn E.; Schimmel, Bernardus C.J.; Marciniak, Danielle M.; Verdonk, Julian C.; Kim, Joo Young; Oh, Youngjoo; Gális, Ivan; Baldwin, Ian T.; Clark, David G.

2011-01-01

R2R3-MYB transcription factors (TFs) are involved in diverse aspects of plant biology. Recently an R2R3-MYB was identified in Petunia x hybrida line P720 to have a role in the transcriptional regulation of floral volatile production. We propose a more foundational role for the R2R3-MYB TF EMISSION OF BENZENOIDS II (EOBII). The homolog of EOBII was isolated and characterized from P. x hybrida ‘Mitchell Diploid’ (MD) and Nicotiana attenuata. For both MD and N. attenuata, EOBII transcript accumulates to high levels in floral tissue with maximum accumulation at flower opening. When EOBII transcript levels are severely reduced using a stable RNAi (ir) approach in MD and N. attenuata, ir-EOBII flowers fail to enter anthesis and prematurely senesce. Transcript accumulation analysis demonstrated core phenylpropanoid pathway transcripts and cell wall modifier transcript levels are altered in ir-EOBII flowers. These flowers can be partially complemented by feeding with a sucrose, t-cinnamic acid, and gibberellic acid solution; presumably restoring cellular aspects sufficient for flower opening. Additionally, if ethylene sensitivity is blocked in either MD or N. attenuata, ir-EOBII flowers enter anthesis. These experiments demonstrate one R2R3-MYB TF can control a highly dynamic process fundamental to sexual reproduction in angiosperms: the opening of flowers. PMID:21464473

High-performance silicon photonic tri-state switch based on balanced nested Mach-Zehnder interferometer.

PubMed

Lu, Zeqin; Celo, Dritan; Mehrvar, Hamid; Bernier, Eric; Chrostowski, Lukas

2017-09-25

This work proposes a novel silicon photonic tri-state (cross/bar/blocking) switch, featuring high-speed switching, broadband operation, and crosstalk-free performance. The switch is designed based on a 2 × 2 balanced nested Mach-Zehnder interferometer structure with carrier injection phase tuning. As compared to silicon photonic dual-state (cross/bar) switches based on Mach-Zehnder interferometers with carrier injection phase tuning, the proposed switch not only has better performance in cross/bar switching but also provides an extra blocking state. The unique blocking state has a great advantage in applications of N × N switch fabrics, where idle switching elements in the fabrics can be configured to the blocking state for crosstalk suppression. According to our numerical experiments on a fully loaded 8 × 8 dilated Banyan switch fabric, the worst output crosstalk of the 8 × 8 switch can be dramatically suppressed by more than 50 dB, by assigning the blocking state to idle switching elements in the fabric. The results of this work can extend the functionality of silicon photonic switches and significantly improve the performance of on-chip N × N photonic switching technologies.

Tapping to a Slow Tempo in the Presence of Simple and Complex Meters Reveals Experience-Specific Biases for Processing Music

PubMed Central

Ullal-Gupta, Sangeeta; Hannon, Erin E.; Snyder, Joel S.

2014-01-01

Musical meters vary considerably across cultures, yet relatively little is known about how culture-specific experience influences metrical processing. In Experiment 1, we compared American and Indian listeners' synchronous tapping to slow sequences. Inter-tone intervals contained silence or to-be-ignored rhythms that were designed to induce a simple meter (familiar to Americans and Indians) or a complex meter (familiar only to Indians). A subset of trials contained an abrupt switch from one rhythm to another to assess the disruptive effects of contradicting the initially implied meter. In the unfilled condition, both groups tapped earlier than the target and showed large tap-tone asynchronies (measured in relative phase). When inter-tone intervals were filled with simple-meter rhythms, American listeners tapped later than targets, but their asynchronies were smaller and declined more rapidly. Likewise, asynchronies rose sharply following a switch away from simple-meter but not from complex-meter rhythm. By contrast, Indian listeners performed similarly across all rhythm types, with asynchronies rapidly declining over the course of complex- and simple-meter trials. For these listeners, a switch from either simple or complex meter increased asynchronies. Experiment 2 tested American listeners but doubled the duration of the synchronization phase prior to (and after) the switch. Here, compared with simple meters, complex-meter rhythms elicited larger asynchronies that declined at a slower rate, however, asynchronies increased after the switch for all conditions. Our results provide evidence that ease of meter processing depends to a great extent on the amount of experience with specific meters. PMID:25075514

Induction of Metamorphosis Causes Differences in Sex-Specific Allocation Patterns in Axolotls (Ambystoma mexicanum) that Have Different Growth Histories.

PubMed

Clarkson, Pamela M; Beachy, Christopher K

2015-12-01

We tested the hypothesis that salamanders growing at different rates would have allocation patterns that differ among male and female metamorphic and larval salamanders. We raised individual axolotls, Ambystoma mexicanum , on four food regimes: constant high growth (throughout the experiment), constant low growth (restricted throughout the experiment), high growth switched to low growth (ad libitum switched after 140 d to restricted), and low growth switched to high growth (restricted switched after 140 d to ad libitum). Because axolotls are obligate paedomorphs, we exposed half of the salamanders to thyroid hormone to induce metamorphosis. We assayed growth and dissected and weighed gonads and fat bodies. Salamanders that were switched from restricted to ad libitum food regime delayed metamorphosis. In all treatment groups, females had larger gonads than males and males had larger fat bodies than females. The association between storage and reproduction differed between larvae and metamorphs and depended on sex.

Age matters: The effect of onset age of video game play on task-switching abilities.

PubMed

Hartanto, Andree; Toh, Wei Xing; Yang, Hwajin

2016-05-01

Although prior research suggests that playing video games can improve cognitive abilities, recent empirical studies cast doubt on such findings (Unsworth et al., 2015). To reconcile these inconsistent findings, we focused on the link between video games and task switching. Furthermore, we conceptualized video-game expertise as the onset age of active video-game play rather than the frequency of recent gameplay, as it captures both how long a person has played video games and whether the individual began playing during periods of high cognitive plasticity. We found that the age of active onset better predicted switch and mixing costs than did frequency of recent gameplay; specifically, players who commenced playing video games at an earlier age reaped greater benefits in terms of task switching than did those who started at a later age. Moreover, improving switch costs required a more extensive period of video-game experience than did mixing costs; this finding suggests that certain cognitive abilities benefit from different amounts of video game experience.

Patient acceptability and experiences of therapeutic switching of proton pump inhibitors within the National Preferred Drugs initiative in Ireland.

PubMed

O'Connor, G; O'Keeffe, D; Darker, C; O'Shea, B

2017-08-01

A 'Preferred Drugs' initiative was introduced into Ireland in 2013. This identified a single recommended drug to be prescribed to patients requiring treatment from a particular class of drugs. This study investigates how patients on established proton pump inhibitor (PPI) therapy experienced the therapeutic switching of their medication to the 'preferred drug', and the extent to which they regarded it as an acceptable practice. The experiences of 61 patients on established proton pump inhibitor (PPI) therapy were sought before and after their drug was switched to the 'preferred drug'. Eighty per cent of patients were happy to switch medications. When asked for their opinions on medications in general, 71% felt doctors should prescribe the least expensive medication, 84% agreed that all licensed medications were safe while 67% felt their GP changing medication for cost reasons was safe. After 8 weeks, 20% of patients had switched back to their old PPI. When asked how they felt about their medication change, 74% felt happy or pleased. The majority of patients in our study were satisfied to have their medication switched. However, prescribers should be mindful that 1 in 5 patients encountered problems as a result of the switching process.

Analysis of optical route in a micro high-speed magneto-optic switch

NASA Astrophysics Data System (ADS)

Weng, Zihua; Yang, Guoguang; Huang, Yuanqing; Chen, Zhimin; Zhu, Yun; Wu, Jinming; Lin, Shufen; Mo, Weiping

2005-02-01

A novel micro high-speed 2x2 magneto-optic switch and its optical route, which is used in high-speed all-optical communication network, is designed and analyzed in this paper. The study of micro high-speed magneto-optic switch mainly involves the optical route and high-speed control technique design. The optical route design covers optical route design of polarization in optical switch, the performance analysis and material selection of magneto-optic crystal and magnetic path design in Faraday rotator. The research of high-speed control technique involves the study of nanosecond pulse generator, high-speed magnetic field and its control technique etc. High-speed current transients from nanosecond pulse generator are used to switch the magnetization of the magneto-optic crystal, which propagates a 1550nm optical beam. The optical route design schemes and electronic circuits of high-speed control technique are both simulated on computer and test by the experiments respectively. The experiment results state that the nanosecond pulse generator can output the pulse with rising edge time 3~35ns, voltage amplitude 10~90V and pulse width 10~100ns. Under the control of CPU singlechip, the optical beam can be stably switched and the switching time is less than 1μs currently.

Speaking Two Languages for the Price of One: Bypassing Language Control Mechanisms via Accessibility-Driven Switches

PubMed Central

Kleinman, Daniel; Gollan, Tamar H.

2016-01-01

How do bilinguals switch easily between languages in everyday conversation, when thousands of studies have found that switching slows responses? Previous research has not considered that although switches may happen for different reasons, only some switches – including those typically studied in laboratory experiments – might be costly. Using a repeated picture naming task, we show that bilinguals can maintain and use two languages as efficiently as a single language, switching between them frequently without any cost, if they switch only when a word is more accessible in the other language. These results suggest that language switch costs arise during lexical selection, that top-down language control mechanisms can be suspended, and that language-mixing efficiency can be strategically increased with instruction. Thus, bilinguals might switch languages spontaneously because doing so is not always costly, and there appears to be greater flexibility and efficiency in the cognitive mechanisms that enable switching than previously assumed. PMID:27016240

Disparate bilingual experiences modulate task-switching advantages: A diffusion-model analysis of the effects of interactional context on switch costs.

PubMed

Hartanto, Andree; Yang, Hwajin

2016-05-01

Drawing on the adaptive control hypothesis (Green & Abutalebi, 2013), we investigated whether bilinguals' disparate interactional contexts modulate task-switching performance. Fifty-eight bilinguals within the single-language context (SLC) and 75 bilinguals within the dual-language context (DLC) were compared in a typical task-switching paradigm. Given that DLC bilinguals switch between languages within the same context, while SLC bilinguals speak only one language in one environment and therefore rarely switch languages, we hypothesized that the two groups' stark difference in their interactional contexts of conversational exchanges would lead to differences in switch costs. As predicted, DLC bilinguals showed smaller switch costs than SLC bilinguals. Our diffusion-model analyses suggest that DLC bilinguals' benefits in switch costs are more likely driven by task-set reconfiguration than by proactive interference. Our findings underscore the modulating role of the interactional context of conversational exchanges in task switching. Copyright © 2016 Elsevier B.V. All rights reserved.

Automation bias: empirical results assessing influencing factors.

PubMed

Goddard, Kate; Roudsari, Abdul; Wyatt, Jeremy C

2014-05-01

To investigate the rate of automation bias - the propensity of people to over rely on automated advice and the factors associated with it. Tested factors were attitudinal - trust and confidence, non-attitudinal - decision support experience and clinical experience, and environmental - task difficulty. The paradigm of simulated decision support advice within a prescribing context was used. The study employed within participant before-after design, whereby 26 UK NHS General Practitioners were shown 20 hypothetical prescribing scenarios with prevalidated correct and incorrect answers - advice was incorrect in 6 scenarios. They were asked to prescribe for each case, followed by being shown simulated advice. Participants were then asked whether they wished to change their prescription, and the post-advice prescription was recorded. Rate of overall decision switching was captured. Automation bias was measured by negative consultations - correct to incorrect prescription switching. Participants changed prescriptions in 22.5% of scenarios. The pre-advice accuracy rate of the clinicians was 50.38%, which improved to 58.27% post-advice. The CDSS improved the decision accuracy in 13.1% of prescribing cases. The rate of automation bias, as measured by decision switches from correct pre-advice, to incorrect post-advice was 5.2% of all cases - a net improvement of 8%. More immediate factors such as trust in the specific CDSS, decision confidence, and task difficulty influenced rate of decision switching. Lower clinical experience was associated with more decision switching. Age, DSS experience and trust in CDSS generally were not significantly associated with decision switching. This study adds to the literature surrounding automation bias in terms of its potential frequency and influencing factors. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Nonlinear optical characterization of graphite oxide thin film by open aperture Z-scan technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sreeja, V. G.; Reshmi, R.; Devasia, Sebin

In this paper we explore the structural characterization of graphite oxide powder prepared from graphite powder by oxidation via modified Hummers method. The nonlinear optical properties of the spin coated graphite oxide thin film is also explored by open aperture Z-Scan technique. Structural and physiochemical properties of the samples were investigated with the help of Fourier Transform Infrared Spectroscopy (FTIR) and Raman Spectroscopy (Raman).The results of FT-IR and Raman spectroscopy showed that the graphite is oxidized by strong oxidants and the oxygen atoms are introduced into the graphite layers forming C=C, O-H and –C-H groups. The synthesized sample has goodmore » crystalline nature with lesser defects. The nonlinear optical property of GO thin film was studied by open aperture Z-Scan technique using Q-switched Nd-Yag Laser at 532 nm. The Z-scan plot showed that the investigated GO thin film has saturable absorption behavior. The nonlinear absorption coefficient and saturation intensity were also estimated to explore its applications in Q switched mode locking laser systems.« less

Nanocrystalline Si pathway induced unipolar resistive switching behavior from annealed Si-rich SiN{sub x}/SiN{sub y} multilayers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Xiaofan; Ma, Zhongyuan, E-mail: zyma@nju.edu.cn; Yang, Huafeng

2014-09-28

Adding a resistive switching functionality to a silicon microelectronic chip is a new challenge in materials research. Here, we demonstrate that unipolar and electrode-independent resistive switching effects can be realized in the annealed Si-rich SiN{sub x}/SiN{sub y} multilayers with high on/off ratio of 10{sup 9}. High resolution transmission electron microscopy reveals that for the high resistance state broken pathways composed of discrete nanocrystalline silicon (nc-Si) exist in the Si nitride multilayers. While for the low resistance state the discrete nc-Si regions is connected, forming continuous nc-Si pathways. Based on the analysis of the temperature dependent I-V characteristics and HRTEM photos,more » we found that the break-and-bridge evolution of nc-Si pathway is the origin of resistive switching memory behavior. Our findings provide insights into the mechanism of the resistive switching behavior in nc-Si films, opening a way for it to be utilized as a material in Si-based memories.« less

Highly integrated 3×3 silicon thermo-optical switch using a single combined phase shifter for optical interconnects.

PubMed

Wang, Wanjun; Zhou, Haifeng; Yang, Jianyi; Wang, Minghua; Jiang, Xiaoqing

2012-06-15

We report on an experimental 3×3 thermo-optical switch on silicon on insulator. By controlling a single combined phase shifter, light from any input waveguide can be directed to any output waveguide, showing a simple control method and highly integrated structure as compared to the conventional multiway optical switches. Furthermore, the proposed optical switch can be generalized to be a 1×N and N×N optical switch without an extra phase shifter. The switch is fabricated by complementary metal oxide semiconductor technology. By experiment, full 3×3 switching functionality is demonstrated at a wavelength of 1.55 μm, with an average cross talk of -11.1  dB and a power consumption of 97.5 mW.

MSiReader v1.0: Evolving Open-Source Mass Spectrometry Imaging Software for Targeted and Untargeted Analyses.

PubMed

Bokhart, Mark T; Nazari, Milad; Garrard, Kenneth P; Muddiman, David C

2018-01-01

A major update to the mass spectrometry imaging (MSI) software MSiReader is presented, offering a multitude of newly added features critical to MSI analyses. MSiReader is a free, open-source, and vendor-neutral software written in the MATLAB platform and is capable of analyzing most common MSI data formats. A standalone version of the software, which does not require a MATLAB license, is also distributed. The newly incorporated data analysis features expand the utility of MSiReader beyond simple visualization of molecular distributions. The MSiQuantification tool allows researchers to calculate absolute concentrations from quantification MSI experiments exclusively through MSiReader software, significantly reducing data analysis time. An image overlay feature allows the incorporation of complementary imaging modalities to be displayed with the MSI data. A polarity filter has also been incorporated into the data loading step, allowing the facile analysis of polarity switching experiments without the need for data parsing prior to loading the data file into MSiReader. A quality assurance feature to generate a mass measurement accuracy (MMA) heatmap for an analyte of interest has also been added to allow for the investigation of MMA across the imaging experiment. Most importantly, as new features have been added performance has not degraded, in fact it has been dramatically improved. These new tools and the improvements to the performance in MSiReader v1.0 enable the MSI community to evaluate their data in greater depth and in less time. Graphical Abstract ᅟ.

Effect of video-game experience and position of flight stick controller on simulated-flight performance.

PubMed

Cho, Bo-Keun; Aghazadeh, Fereydoun; Al-Qaisi, Saif

2012-01-01

The purpose of this study was to determine the effects of video-game experience and flight-stick position on flying performance. The study divided participants into 2 groups; center- and side-stick groups, which were further divided into high and low level of video-game experience subgroups. The experiment consisted of 7 sessions of simulated flying, and in the last session, the flight stick controller was switched to the other position. Flight performance was measured in terms of the deviation of heading, altitude, and airspeed from their respective requirements. Participants with high experience in video games performed significantly better (p < .001) than the low-experienced group. Also, participants performed significantly better (p < .001) with the center-stick than the side-stick. When the side-stick controller was switched to the center-stick position, performance scores continued to increase (0.78 %). However, after switching from a center- to a side-stick controller, performance scores decreased (4.8%).

Language switching-but not foreign language use per se-reduces the framing effect.

PubMed

Oganian, Y; Korn, C W; Heekeren, H R

2016-01-01

Recent studies reported reductions of well-established biases in decision making under risk, such as the framing effect, during foreign language (FL) use. These modulations were attributed to the use of FL itself, which putatively entails an increase in emotional distance. A reduced framing effect in this setting, however, might also result from enhanced cognitive control associated with language-switching in mixed-language contexts, an account that has not been tested yet. Here we assess predictions of the 2 accounts in 2 experiments with over 1,500 participants. In Experiment 1, we tested a central prediction of the emotional distance account, namely that the framing effect would be reduced at low, but not high, FL proficiency levels. We found a strong framing effect in the native language, and surprisingly also in the foreign language, independent of proficiency. In Experiment 2, we orthogonally manipulated foreign language use and language switching to concurrently test the validity of both accounts. As in Experiment 1, foreign language use per se had no effect on framing. Crucially, the framing effect was reduced following a language switch, both when switching into the foreign and the native language. Thus, our results suggest that reduced framing effects are not mediated by increased emotional distance in a foreign language, but by transient enhancement of cognitive control, putting the interplay of bilingualism and decision making in a new light. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Superconducting Switch for Fast On-Chip Routing of Quantum Microwave Fields

NASA Astrophysics Data System (ADS)

Pechal, M.; Besse, J.-C.; Mondal, M.; Oppliger, M.; Gasparinetti, S.; Wallraff, A.

2016-08-01

A switch capable of routing microwave signals at cryogenic temperatures is a desirable component for state-of-the-art experiments in many fields of applied physics, including but not limited to quantum-information processing, communication, and basic research in engineered quantum systems. Conventional mechanical switches provide low insertion loss but disturb operation of dilution cryostats and the associated experiments by heat dissipation. Switches based on semiconductors or microelectromechanical systems have a lower thermal budget but are not readily integrated with current superconducting circuits. Here we design and test an on-chip switch built by combining tunable transmission-line resonators with microwave beam splitters. The device is superconducting and as such dissipates a negligible amount of heat. It is compatible with current superconducting circuit fabrication techniques, operates with a bandwidth exceeding 100 MHz, is capable of handling photon fluxes on the order of 1 05 μ s-1 , equivalent to powers exceeding -90 dBm , and can be switched within approximately 6-8 ns. We successfully demonstrate operation of the device in the quantum regime by integrating it on a chip with a single-photon source and using it to route nonclassical itinerant microwave fields at the single-photon level.

A multiple camera tongue switch for a child with severe spastic quadriplegic cerebral palsy.

PubMed

Leung, Brian; Chau, Tom

2010-01-01

The present study proposed a video-based access technology that facilitated a non-contact tongue protrusion access modality for a 7-year-old boy with severe spastic quadriplegic cerebral palsy (GMFCS level 5). The proposed system featured a centre camera and two peripheral cameras to extend coverage of the frontal face view of this user for longer durations. The child participated in a descriptive case study. The participant underwent 3 months of tongue protrusion training while the multiple camera tongue switch prototype was being prepared. Later, the participant was brought back for five experiment sessions where he worked on a single-switch picture matching activity, using the multiple camera tongue switch prototype in a controlled environment. The multiple camera tongue switch achieved an average sensitivity of 82% and specificity of 80%. In three of the experiment sessions, the peripheral cameras were associated with most of the true positive switch activations. These activations would have been missed by a centre-camera-only setup. The study demonstrated proof-of-concept of a non-contact tongue access modality implemented by a video-based system involving three cameras and colour video processing.

Copper atomic-scale transistors.

PubMed

Xie, Fangqing; Kavalenka, Maryna N; Röger, Moritz; Albrecht, Daniel; Hölscher, Hendrik; Leuthold, Jürgen; Schimmel, Thomas

2017-01-01

We investigated copper as a working material for metallic atomic-scale transistors and confirmed that copper atomic-scale transistors can be fabricated and operated electrochemically in a copper electrolyte (CuSO 4 + H 2 SO 4 ) in bi-distilled water under ambient conditions with three microelectrodes (source, drain and gate). The electrochemical switching-on potential of the atomic-scale transistor is below 350 mV, and the switching-off potential is between 0 and -170 mV. The switching-on current is above 1 μA, which is compatible with semiconductor transistor devices. Both sign and amplitude of the voltage applied across the source and drain electrodes ( U bias ) influence the switching rate of the transistor and the copper deposition on the electrodes, and correspondingly shift the electrochemical operation potential. The copper atomic-scale transistors can be switched using a function generator without a computer-controlled feedback switching mechanism. The copper atomic-scale transistors, with only one or two atoms at the narrowest constriction, were realized to switch between 0 and 1 G 0 ( G 0 = 2e 2 /h; with e being the electron charge, and h being Planck's constant) or 2 G 0 by the function generator. The switching rate can reach up to 10 Hz. The copper atomic-scale transistor demonstrates volatile/non-volatile dual functionalities. Such an optimal merging of the logic with memory may open a perspective for processor-in-memory and logic-in-memory architectures, using copper as an alternative working material besides silver for fully metallic atomic-scale transistors.

Eslicarbazepine acetate: its effectiveness as adjunctive therapy in clinical trials and open studies.

PubMed

Shorvon, S D; Trinka, E; Steinhoff, B J; Holtkamp, M; Villanueva, V; Peltola, J; Ben-Menachem, E

2017-03-01

Eslicarbazepine acetate (ESL) is a once-daily antiepileptic drug that is approved as adjunctive therapy in adults with focal-onset seizures. Following oral administration, ESL is rapidly metabolized to its active metabolite, eslicarbazepine, which acts primarily by enhancing slow inactivation of voltage-gated sodium channels. The efficacy and safety/tolerability of ESL in the adjunctive setting were established in a comprehensive Phase III program (n = 1702 randomized patients) and this evidence has been supported by several open studies (n = 864). ESL treatment has demonstrated improvements in health-related quality of life, in both randomized clinical trials and open studies. ESL has also been shown to be usually well tolerated and efficacious when used in the adjunctive setting in elderly patients. The effectiveness of ESL as the only add-on to antiepileptic drug monotherapy has been demonstrated in a multinational study (n = 219), subgroup analyses of which have also shown it to be efficacious and generally well tolerated in patients who had previously not responded to carbamazepine therapy. Open studies have also demonstrated improvements in tolerability in patients switched overnight from oxcarbazepine to ESL. Due to differences in pharmacokinetics, pharmacodynamics, and metabolism, there may be clinical situations in which it is appropriate to consider switching patients from oxcarbazepine or carbamazepine to ESL.

Comparison of body-powered voluntary opening and voluntary closing prehensor for activities of daily life.

PubMed

Berning, Kelsey; Cohick, Sarah; Johnson, Reva; Miller, Laura Ann; Sensinger, Jonathon W

2014-01-01

Persons with an upper-limb amputation who use a body-powered prosthesis typically control the prehensor through contralateral shoulder movement, which is transmitted through a Bowden cable. Increased cable tension either opens or closes the prehensor; when tension is released, some passive element, such as a spring, returns the prehensor to the default state (closed or open). In this study, we used the Southampton Hand Assessment Procedure to examine functional differences between these two types of prehensors in 29 nondisabled subjects (who used a body-powered bypass prosthesis) and 2 persons with unilateral transradial amputations (who used a conventional body-powered device). We also administered a survey to determine whether subjects preferred one prehensor or the other for specific tasks, with a long-term goal of assessing whether a prehensor that could switch between both modes would be advantageous. We found that using the voluntary closing prehensor was 1.3 s faster (p = 0.02) than using the voluntary opening prehensor, across tasks, and that there was consensus among subjects on which types of tasks they preferred to do with each prehensor type. Twenty-five subjects wanted a device that could switch between the two modes in order to perform particular tasks.

A proposal for an SDN-based SIEPON architecture

NASA Astrophysics Data System (ADS)

Khalili, Hamzeh; Sallent, Sebastià; Piney, José Ramón; Rincón, David

2017-11-01

Passive Optical Network (PON) elements such as Optical Line Terminal (OLT) and Optical Network Units (ONUs) are currently managed by inflexible legacy network management systems. Software-Defined Networking (SDN) is a new networking paradigm that improves the operation and management of networks. In this paper, we propose a novel architecture, based on the SDN concept, for Ethernet Passive Optical Networks (EPON) that includes the Service Interoperability standard (SIEPON). In our proposal, the OLT is partially virtualized and some of its functionalities are allocated to the core network management system, while the OLT itself is replaced by an OpenFlow (OF) switch. A new MultiPoint MAC Control (MPMC) sublayer extension based on the OpenFlow protocol is presented. This would allow the SDN controller to manage and enhance the resource utilization, flow monitoring, bandwidth assignment, quality-of-service (QoS) guarantees, and energy management of the optical network access, to name a few possibilities. The OpenFlow switch is extended with synchronous ports to retain the time-critical nature of the EPON network. OpenFlow messages are also extended with new functionalities to implement the concept of EPON Service Paths (ESPs). Our simulation-based results demonstrate the effectiveness of the new architecture, while retaining a similar (or improved) performance in terms of delay and throughput when compared to legacy PONs.

The Monty Hall dilemma in pigeons: effect of investment in initial choice.

PubMed

Stagner, Jessica P; Rayburn-Reeves, Rebecca; Zentall, Thomas R

2013-10-01

In the Monty Hall dilemma, humans are initially given a choice among three alternatives, one of which has a hidden prize. After choosing, but before it is revealed whether they have won the prize, they are shown that one of the remaining alternatives does not have the prize. They are then asked whether they want to stay with their original choice or switch to the remaining alternative. Although switching results in obtaining the prize two thirds of the time, humans consistently fail to adopt the optimal strategy of switching even after considerable training. Interestingly, there is evidence that pigeons show more optimal switching performance with this task than humans. Because humans often view even random choices already made as being more valuable than choices not made, we reasoned that if pigeons made a greater investment, it might produce an endowment or ownership effect resulting in more human-like suboptimal performance. On the other hand, the greater investment in the initial choice by the pigeons might facilitate switching behavior by helping them to better discriminate their staying versus switching behavior. In Experiment 1, we examined the effect of requiring pigeons to make a greater investment in their initial choice (20 pecks rather than the usual 1 peck). We found that the increased response requirement facilitated acquisition of the switching response. In Experiment 2, we showed that facilitation of switching due to the increased response requirement did not result from extinction of responding to the initially chosen location.

How Traumatic Violence Permanently Changes Shopping Behavior.

PubMed

Sigirci, Ozge; Rockmore, Marc; Wansink, Brian

2016-01-01

Traumatic experiences - such as combat, living in a conflict country or war-torn nation, or experiencing a violent crime or natural disaster - change social relationships and may also influence a life-time of consumer relationships with brands and shopping. Our focus on this previously overlooked area is centered on an analysis of the long-term shopping habits of 355 combat veterans. We show that those who experienced heavy trauma (e.g., heavy combat) exhibited similar disconnection from brands as others have experienced in social relationships. They became more transactional in that they were more open to switching brands, to trying new products, and buying the least expensive alternative (p < 0.01). In contrast, those who had experienced a light trauma were more influenced by ads and more open to buying brands even when they cost more (p < 0.00). Trauma, such as combat, may change one's decision horizon. Functionality and price become more important, which is consistent with the idea that they are more focused on the present moment than on building on the past or saving for the future.

How Traumatic Violence Permanently Changes Shopping Behavior

PubMed Central

Sigirci, Ozge; Rockmore, Marc; Wansink, Brian

2016-01-01

Traumatic experiences – such as combat, living in a conflict country or war-torn nation, or experiencing a violent crime or natural disaster – change social relationships and may also influence a life-time of consumer relationships with brands and shopping. Our focus on this previously overlooked area is centered on an analysis of the long-term shopping habits of 355 combat veterans. We show that those who experienced heavy trauma (e.g., heavy combat) exhibited similar disconnection from brands as others have experienced in social relationships. They became more transactional in that they were more open to switching brands, to trying new products, and buying the least expensive alternative (p < 0.01). In contrast, those who had experienced a light trauma were more influenced by ads and more open to buying brands even when they cost more (p < 0.00). Trauma, such as combat, may change one’s decision horizon. Functionality and price become more important, which is consistent with the idea that they are more focused on the present moment than on building on the past or saving for the future. PMID:27656152

Haptic/graphic rehabilitation: integrating a robot into a virtual environment library and applying it to stroke therapy.

PubMed

Sharp, Ian; Patton, James; Listenberger, Molly; Case, Emily

2011-08-08

Recent research that tests interactive devices for prolonged therapy practice has revealed new prospects for robotics combined with graphical and other forms of biofeedback. Previous human-robot interactive systems have required different software commands to be implemented for each robot leading to unnecessary developmental overhead time each time a new system becomes available. For example, when a haptic/graphic virtual reality environment has been coded for one specific robot to provide haptic feedback, that specific robot would not be able to be traded for another robot without recoding the program. However, recent efforts in the open source community have proposed a wrapper class approach that can elicit nearly identical responses regardless of the robot used. The result can lead researchers across the globe to perform similar experiments using shared code. Therefore modular "switching out"of one robot for another would not affect development time. In this paper, we outline the successful creation and implementation of a wrapper class for one robot into the open-source H3DAPI, which integrates the software commands most commonly used by all robots.

Study of switching behavior of exchange-coupled nanomagnets by transverse magnetization metrology

NASA Astrophysics Data System (ADS)

Dey, Himadri S.; Csaba, Gyorgy; Bernstein, Gary H.; Porod, Wolfgang

2017-05-01

We investigate the static switching modes of nanomagnets patterned from antiferromagnetically exchange-coupled magnetic multilayers, and compare them to nanomagnets having only dipole coupling between the ferromagnetic layers. Vibrating sample magnetometry experiments, supported by micromagnetic simulations, reveal two distinct switching mechanisms between the exchange-coupled and only dipole-coupled nanomagnets. The exchange-coupled nanomagnets exhibit gradual switching of the layers, dictated by the strong antiferromagnetic exchange coupling present between the layers. However, the layers of the only dipole-coupled nanomagnets show abrupt nucleation/growth type switching. A comprehensive understanding of the switching modes of such layered and patterned systems can add new insight into the reversal mechanisms of similar systems employed for spintronic and magneto-logic device applications.

29 CFR 1926.910 - Inspection after blasting.

Code of Federal Regulations, 2010 CFR

2010-07-01

... disconnected from the blasting machine, or where power switches are used, they shall be locked open or in the off position. (b) Sufficient time shall be allowed, not less than 15 minutes in tunnels, for the smoke...

29 CFR 1926.910 - Inspection after blasting.

Code of Federal Regulations, 2011 CFR

2011-07-01

... disconnected from the blasting machine, or where power switches are used, they shall be locked open or in the off position. (b) Sufficient time shall be allowed, not less than 15 minutes in tunnels, for the smoke...

29 CFR 1926.910 - Inspection after blasting.

Code of Federal Regulations, 2012 CFR

2012-07-01

... disconnected from the blasting machine, or where power switches are used, they shall be locked open or in the off position. (b) Sufficient time shall be allowed, not less than 15 minutes in tunnels, for the smoke...

29 CFR 1926.910 - Inspection after blasting.

Code of Federal Regulations, 2014 CFR

2014-07-01

... disconnected from the blasting machine, or where power switches are used, they shall be locked open or in the off position. (b) Sufficient time shall be allowed, not less than 15 minutes in tunnels, for the smoke...

29 CFR 1926.910 - Inspection after blasting.

Code of Federal Regulations, 2013 CFR

2013-07-01

... disconnected from the blasting machine, or where power switches are used, they shall be locked open or in the off position. (b) Sufficient time shall be allowed, not less than 15 minutes in tunnels, for the smoke...

Exploring the repetition bias in voluntary task switching.

PubMed

Mittelstädt, Victor; Dignath, David; Schmidt-Ott, Magdalena; Kiesel, Andrea

2018-01-01

In the voluntary task-switching paradigm, participants are required to randomly select tasks. We reasoned that the consistent finding of a repetition bias (i.e., participants repeat tasks more often than expected by chance) reflects reasonable adaptive task selection behavior to balance the goal of random task selection with the goals to minimize the time and effort for task performance. We conducted two experiments in which participants were provided with variable amount of preview for the non-chosen task stimuli (i.e., potential switch stimuli). We assumed that switch stimuli would initiate some pre-processing resulting in improved performance in switch trials. Results showed that reduced switch costs due to extra-preview in advance of each trial were accompanied by more task switches. This finding is in line with the characteristics of rational adaptive behavior. However, participants were not biased to switch tasks more often than chance despite large switch benefits. We suggest that participants might avoid effortful additional control processes that modulate the effects of preview on task performance and task choice.

Study on the transient properties of amorphous solar cells

NASA Astrophysics Data System (ADS)

Smrity, Manu; Dhariwal, S. R.

2016-05-01

The transient response for the solar cell when switched off from steady-state can provide useful information about the quality of the material used for fabrication of the device. In this paper we shall discuss the photovoltaic transients of amorphous silicon solar cells when switched off from open circuit configuration and illuminated by electrical pulse. The open-circuit voltage (Voc) decay can be performed by two methods, by optical excitation and by electrical pulse. When one of carriers has a concentration much higher than the other the photoconductivity is dominated by majority carriers; in that case the Voc decay which depends on the np product can be used as complementary method for obtaining information about the minority carriers. Also the series resistance drop in an electrical Voc decay method can be used to obtain a IJ't product as an additional information regarding the material of the device.

Diffusive flux in a model of stochastically gated oxygen transport in insect respiration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berezhkovskii, Alexander M.; Shvartsman, Stanislav Y.

Oxygen delivery to insect tissues is controlled by transport through a branched tubular network that is connected to the atmosphere by valve-like gates, known as spiracles. In certain physiological regimes, the spiracles appear to be randomly switching between open and closed states. Quantitative analysis of this regime leads a reaction-diffusion problem with stochastically switching boundary condition. We derive an expression for the diffusive flux at long times in this problem. Our approach starts with the derivation of the passage probability for a single particle that diffuses between a stochastically gated boundary, which models the opening and closing spiracle, and themore » perfectly absorbing boundary, which models oxygen absorption by the tissue. This passage probability is then used to derive an expression giving the diffusive flux as a function of the geometric parameters of the tube and characteristic time scales of diffusion and gate dynamics.« less

Diffusive flux in a model of stochastically gated oxygen transport in insect respiration.

PubMed

Berezhkovskii, Alexander M; Shvartsman, Stanislav Y

2016-05-28

Oxygen delivery to insect tissues is controlled by transport through a branched tubular network that is connected to the atmosphere by valve-like gates, known as spiracles. In certain physiological regimes, the spiracles appear to be randomly switching between open and closed states. Quantitative analysis of this regime leads a reaction-diffusion problem with stochastically switching boundary condition. We derive an expression for the diffusive flux at long times in this problem. Our approach starts with the derivation of the passage probability for a single particle that diffuses between a stochastically gated boundary, which models the opening and closing spiracle, and the perfectly absorbing boundary, which models oxygen absorption by the tissue. This passage probability is then used to derive an expression giving the diffusive flux as a function of the geometric parameters of the tube and characteristic time scales of diffusion and gate dynamics.

Production of atmospheric-pressure glow discharge in nitrogen using needle-array electrode

NASA Astrophysics Data System (ADS)

Takaki, K.; Hosokawa, M.; Sasaki, T.; Mukaigawa, S.; Fujiwara, T.

2005-04-01

An atmospheric pressure glow discharge was generated using a needle-array electrode in nitrogen, and the voltage-current characteristics of the glow discharge were obtained in a range from 1 mA to 60 A. A pulsed high voltage with short rise time under 10 ns was employed to generate streamer discharges simultaneously at all needle tips. The large number of streamer discharges prevented the glow-to-arc transition caused by inhomogeneous thermalization. Semiconductor opening switch diodes were employed as an opening switch to shorten the rise time. The glow voltage was almost constant until the discharge current became 0.3 A, whereas the voltage increased with the current higher than 0.3 A. Electron density and temperature in a positive column of the glow discharge at 60 A were obtained to 1.4×1012cm-3 and 1.3 eV from calculation based on nitrogen swarm data.

Development of modular scalable pulsed power systems for high power magnetized plasma experiments

NASA Astrophysics Data System (ADS)

Bean, I. A.; Weber, T. E.; Adams, C. S.; Henderson, B. R.; Klim, A. J.

2017-10-01

New pulsed power switches and trigger drivers are being developed in order to explore higher energy regimes in the Magnetic Shock Experiment (MSX) at Los Alamos National Laboratory. To achieve the required plasma velocities, high-power (approx. 100 kV, 100s of kA), high charge transfer (approx. 1 C), low-jitter (few ns) gas switches are needed. A study has been conducted on the effects of various electrode geometries and materials, dielectric media, and triggering strategies; resulting in the design of a low-inductance annular field-distortion switch, optimized for use with dry air at 90 psig, and triggered by a low-jitter, rapid rise-time solid-state Linear Transformer Driver. The switch geometry and electrical characteristics are designed to be compatible with Syllac style capacitors, and are intended to be deployed in modular configurations. The scalable nature of this approach will enable the rapid design and implementation of a wide variety of high-power magnetized plasma experiments. This work is supported by the U.S. Department of Energy, National Nuclear Security Administration. Approved for unlimited release, LA-UR-17-2578.

Micro rectennas: Brownian ratchets for thermal-energy harvesting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pan, Y.; Powell, C. V.; Balocco, C., E-mail: claudio.balocco@durham.ac.uk

2014-12-22

We experimentally demonstrated the operation of a rectenna for harvesting thermal (blackbody) radiation and converting it into dc electric power. The device integrates an ultrafast rectifier, the self-switching nanodiode, with a wideband log-periodic spiral microantenna. The radiation from the thermal source drives the rectenna out of thermal equilibrium, permitting the rectification of the excess thermal fluctuations from the antenna. The power conversion efficiency increases with the source temperatures up to 0.02% at 973 K. The low efficiency is attributed mainly to the impedance mismatch between antenna and rectifier, and partially to the large field of view of the antenna. Our devicemore » not only opens a potential solution for harvesting thermal energy but also provides a platform for experimenting with Brownian ratchets.« less

Water heater control module

DOEpatents

Hammerstrom, Donald J

2013-11-26

An advanced electric water heater control system that interfaces with a high temperature cut-off thermostat and an upper regulating thermostat. The system includes a control module that is electrically connected to the high-temperature cut-off thermostat and the upper regulating thermostat. The control module includes a switch to open or close the high-temperature cut-off thermostat and the upper regulating thermostat. The control module further includes circuitry configured to control said switch in response to a signal selected from the group of an autonomous signal, a communicated signal, and combinations thereof.

When Language Switching has No Apparent Cost: Lexical Access in Sentence Context

PubMed Central

Gullifer, Jason W.; Kroll, Judith F.; Dussias, Paola E.

2013-01-01

We report two experiments that investigate the effects of sentence context on bilingual lexical access in Spanish and English. Highly proficient Spanish-English bilinguals read sentences in Spanish and English that included a marked word to be named. The word was either a cognate with similar orthography and/or phonology in the two languages, or a matched non-cognate control. Sentences appeared in one language alone (i.e., Spanish or English) and target words were not predictable on the basis of the preceding semantic context. In Experiment 1, we mixed the language of the sentence within a block such that sentences appeared in an alternating run in Spanish or in English. These conditions partly resemble normally occurring inter-sentential code-switching. In these mixed-language sequences, cognates were named faster than non-cognates in both languages. There were no effects of switching the language of the sentence. In Experiment 2, with Spanish-English bilinguals matched closely to those who participated in the first experiment, we blocked the language of the sentences to encourage language-specific processes. The results were virtually identical to those of the mixed-language experiment. In both cases, target cognates were named faster than non-cognates, and the magnitude of the effect did not change according to the broader context. Taken together, the results support the predictions of the Bilingual Interactive Activation + Model (Dijkstra and van Heuven, 2002) in demonstrating that bilingual lexical access is language non-selective even under conditions in which language-specific cues should enable selective processing. They also demonstrate that, in contrast to lexical switching from one language to the other, inter-sentential code-switching of the sort in which bilinguals frequently engage, imposes no significant costs to lexical processing. PMID:23750141

Distinguishing the rates of gene activation from phenotypic variations.

PubMed

Chen, Ye; Lv, Cheng; Li, Fangting; Li, Tiejun

2015-06-18

Stochastic genetic switching driven by intrinsic noise is an important process in gene expression. When the rates of gene activation/inactivation are relatively slow, fast, or medium compared with the synthesis/degradation rates of mRNAs and proteins, the variability of protein and mRNA levels may exhibit very different dynamical patterns. It is desirable to provide a systematic approach to identify their key dynamical features in different regimes, aiming at distinguishing which regime a considered gene regulatory network is in from their phenotypic variations. We studied a gene expression model with positive feedbacks when genetic switching rates vary over a wide range. With the goal of providing a method to distinguish the regime of the switching rates, we first focus on understanding the essential dynamics of gene expression system in different cases. In the regime of slow switching rates, we found that the effective dynamics can be reduced to independent evolutions on two separate layers corresponding to gene activation and inactivation states, and the transitions between two layers are rare events, after which the system goes mainly along deterministic ODE trajectories on a particular layer to reach new steady states. The energy landscape in this regime can be well approximated by using Gaussian mixture model. In the regime of intermediate switching rates, we analyzed the mean switching time to investigate the stability of the system in different parameter ranges. We also discussed the case of fast switching rates from the viewpoint of transition state theory. Based on the obtained results, we made a proposal to distinguish these three regimes in a simulation experiment. We identified the intermediate regime from the fact that the strength of cellular memory is lower than the other two cases, and the fast and slow regimes can be distinguished by their different perturbation-response behavior with respect to the switching rates perturbations. We proposed a simulation experiment to distinguish the slow, intermediate and fast regimes, which is the main point of our paper. In order to achieve this goal, we systematically studied the essential dynamics of gene expression system when the switching rates are in different regimes. Our theoretical understanding provides new insights on the gene expression experiments.

Reduced Fluorescent Protein Switching Fatigue by Binding-Induced Emissive State Stabilization

PubMed Central

Dedecker, Peter

2017-01-01

Reversibly switchable fluorescent proteins (RSFPs) enable advanced fluorescence imaging, though the performance of this imaging crucially depends on the properties of the labels. We report on the use of an existing small binding peptide, named Enhancer, to modulate the spectroscopic properties of the recently developed rsGreen series of RSFPs. Fusion constructs of Enhancer with rsGreen1 and rsGreenF revealed an increased molecular brightness and pH stability, although expression in living E. coli or HeLa cells resulted in a decrease of the overall emission. Surprisingly, Enhancer binding also increased off-switching speed and resistance to switching fatigue. Further investigation suggested that the RSFPs can interconvert between fast- and slow-switching emissive states, with the overall protein population gradually converting to the slow-switching state through irradiation. The Enhancer modulates the spectroscopic properties of both states, but also preferentially stabilizes the fast-switching state, supporting the increased fatigue resistance. This work demonstrates how the photo-physical properties of RSFPs can be influenced by their binding to other small proteins, which opens up new horizons for applications that may require such modulation. Furthermore, we provide new insights into the photoswitching kinetics that should be of general consideration when developing new RSFPs with improved or different photochromic properties. PMID:28930199

Super Nonlinear Electrodeposition-Diffusion-Controlled Thin-Film Selector.

PubMed

Ji, Xinglong; Song, Li; He, Wei; Huang, Kejie; Yan, Zhiyuan; Zhong, Shuai; Zhang, Yishu; Zhao, Rong

2018-03-28

Selector elements with high nonlinearity are an indispensable part in constructing high density, large-scale, 3D stackable emerging nonvolatile memory and neuromorphic network. Although significant efforts have been devoted to developing novel thin-film selectors, it remains a great challenge in achieving good switching performance in the selectors to satisfy the stringent electrical criteria of diverse memory elements. In this work, we utilized high-defect-density chalcogenide glass (Ge 2 Sb 2 Te 5 ) in conjunction with high mobility Ag element (Ag-GST) to achieve a super nonlinear selective switching. A novel electrodeposition-diffusion dynamic selector based on Ag-GST exhibits superior selecting performance including excellent nonlinearity (<5 mV/dev), ultra-low leakage (<10 fA), and bidirectional operation. With the solid microstructure evidence and dynamic analyses, we attributed the selective switching to the competition between the electrodeposition and diffusion of Ag atoms in the glassy GST matrix under electric field. A switching model is proposed, and the in-depth understanding of the selective switching mechanism offers an insight of switching dynamics for the electrodeposition-diffusion-controlled thin-film selector. This work opens a new direction of selector designs by combining high mobility elements and high-defect-density chalcogenide glasses, which can be extended to other materials with similar properties.

Selective control of multiple ferroelectric switching pathways using a trailing flexoelectric field

NASA Astrophysics Data System (ADS)

Park, Sung Min; Wang, Bo; Das, Saikat; Chae, Seung Chul; Chung, Jin-Seok; Yoon, Jong-Gul; Chen, Long-Qing; Yang, Sang Mo; Noh, Tae Won

2018-05-01

Flexoelectricity is an electromechanical coupling between electrical polarization and a strain gradient1 that enables mechanical manipulation of polarization without applying an electrical bias2,3. Recently, flexoelectricity was directly demonstrated by mechanically switching the out-of-plane polarization of a uniaxial system with a scanning probe microscope tip3,4. However, the successful application of flexoelectricity in low-symmetry multiaxial ferroelectrics and therefore active manipulation of multiple domains via flexoelectricity have not yet been achieved. Here, we demonstrate that the symmetry-breaking flexoelectricity offers a powerful route for the selective control of multiple domain switching pathways in multiaxial ferroelectric materials. Specifically, we use a trailing flexoelectric field that is created by the motion of a mechanically loaded scanning probe microscope tip. By controlling the SPM scan direction, we can deterministically select either stable 71° ferroelastic switching or 180° ferroelectric switching in a multiferroic magnetoelectric BiFeO3 thin film. Phase-field simulations reveal that the amplified in-plane trailing flexoelectric field is essential for this domain engineering. Moreover, we show that mechanically switched domains have a good retention property. This work opens a new avenue for the deterministic selection of nanoscale ferroelectric domains in low-symmetry materials for non-volatile magnetoelectric devices and multilevel data storage.

Anomalous Resistance Hysteresis in Oxide ReRAM: Oxygen Evolution and Reincorporation Revealed by In Situ TEM.

PubMed

Cooper, David; Baeumer, Christoph; Bernier, Nicolas; Marchewka, Astrid; La Torre, Camilla; Dunin-Borkowski, Rafal E; Menzel, Stephan; Waser, Rainer; Dittmann, Regina

2017-06-01

The control and rational design of redox-based memristive devices, which are highly attractive candidates for next-generation nonvolatile memory and logic applications, is complicated by competing and poorly understood switching mechanisms, which can result in two coexisting resistance hystereses that have opposite voltage polarity. These competing processes can be defined as regular and anomalous resistive switching. Despite significant characterization efforts, the complex nanoscale redox processes that drive anomalous resistive switching and their implications for current transport remain poorly understood. Here, lateral and vertical mapping of O vacancy concentrations is used during the operation of such devices in situ in an aberration corrected transmission electron microscope to explain the anomalous switching mechanism. It is found that an increase (decrease) in the overall O vacancy concentration within the device after positive (negative) biasing of the Schottky-type electrode is associated with the electrocatalytic release and reincorporation of oxygen at the electrode/oxide interface and is responsible for the resistance change. This fundamental insight presents a novel perspective on resistive switching processes and opens up new technological opportunities for the implementation of memristive devices, as anomalous switching can now be suppressed selectively or used deliberately to achieve the desirable so-called deep Reset. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A packet switched communications system for GRO

NASA Astrophysics Data System (ADS)

Husain, Shabu; Yang, Wen-Hsing; Vadlamudi, Rani; Valenti, Joseph

1993-11-01

This paper describes the packet switched Instrumenters Communication System (ICS) that was developed for the Command Management Facility at GSFC to support the Gamma Ray Observatory (GRO) spacecraft. The GRO ICS serves as a vital science data acquisition link to the GRO scientists to initiate commands for their spacecraft instruments. The system is ready to send and receive messages at any time, 24 hours a day and seven days a week. The system is based on X.25 and the International Standard Organization's (ISO) 7-layer Open Systems Interconnection (OSI) protocol model and has client and server components. The components of the GRO ICS are discussed along with how the Communications Subsystem for Interconnection (CSFI) and Network Control Program Packet Switching Interface (NPSI) software are used in the system.

Circular polarization switching and bistability in an optically injected 1300 nm spin-vertical cavity surface emitting laser

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alharthi, S. S., E-mail: ssmalh@essex.ac.uk; Henning, I. D.; Adams, M. J.

We report the experimental observation of circular polarization switching (PS) and polarization bistability (PB) in a 1300 nm dilute nitride spin-vertical cavity surface emitting laser (VCSEL). We demonstrate that the circularly polarized optical signal at 1300 nm can gradually or abruptly switch the polarization ellipticity of the spin-VCSEL from right-to-left circular polarization and vice versa. Moreover, different forms of PS and PB between right- and left-circular polarizations are observed by controlling the injection strength and the initial wavelength detuning. These results obtained at the telecom wavelength of 1300 nm open the door for novel uses of spin-VCSELs in polarization sensitive applications in futuremore » optical systems.« less

Anisotropic Babinet-Invertible Metasurfaces to Realize Transmission-Reflection Switching for Orthogonal Polarizations of Light

NASA Astrophysics Data System (ADS)

Nakata, Yosuke; Urade, Yoshiro; Okimura, Kunio; Nakanishi, Toshihiro; Miyamaru, Fumiaki; Takeda, Mitsuo Wada; Kitano, Masao

2016-10-01

The electromagnetic properties of an extremely thin metallic checkerboard drastically change from resonant reflection (transmission) to resonant transmission (reflection) when the local electrical conductivity at the interconnection points of the checkerboard is switched. To date, such critical transitions of metasurfaces have been applied only when they have fourfold rotational symmetry, and their application to polarization control, which requires anisotropy, has been unexplored. To overcome this applicability limitation and open up alternative pathways for dynamic deep-subwavelength polarization control by utilizing critical transitions of checkerboardlike metasurfaces, we introduce a universal class of anisotropic Babinet-invertible metasurfaces enabling transmission-reflection switching for each orthogonally polarized wave. As an application of anisotropic Babinet-invertible metasurfaces, we experimentally realize a reconfigurable terahertz polarizer whose transmitting axis can be dynamically rotated by 90°.

Superconducting coil system and methods of assembling the same

DOEpatents

Rajput-Ghoshal, Renuka; Rochford, James H.; Ghoshal, Probir K.

2016-01-19

A superconducting magnet apparatus is provided. The superconducting magnet apparatus includes a power source configured to generate a current; a first switch coupled in parallel to the power source; a second switch coupled in series to the power source; a coil coupled in parallel to the first switch and the second switch; and a passive quench protection device coupled to the coil and configured to by-pass the current around the coil and to decouple the coil from the power source when the coil experiences a quench.

Application of Improved Genetic Algorithm to Service Restoration Problem for Distribution Systems

NASA Astrophysics Data System (ADS)

Michibata, Ikuo; Aoki, Hidenori

The problem of recovery from power-system failures is the problem of handling operations that make it possible to supply power from other lines in response to power-system failures or construction by switching between the opened and closed states of sectionalizing switches. Considerable research has already been conducted with regard to this issue. This paper addresses the issue of determining target systems for final recovery in cases when some sections remain subject to power failure (i.e., sound bank capacity < load capacity). For this purpose, intersection is conducted only for parameters within such power-failure sections. In such research, calculations are implemented by setting a value of 2 to the sectionalizing switches of a single parameter. In addition, when the state of a sound section changes due to mutation improvements, the method of simultaneously changing the selected points and neighboring sectionalizing switches is applied. It is clear that the proposed method, consisting of conventional GA only, is superior in terms of average fitness values.

Direct observation of oxygen vacancy-driven structural and resistive phase transitions in La2/3Sr1/3MnO3

NASA Astrophysics Data System (ADS)

Yao, Lide; Inkinen, Sampo; van Dijken, Sebastiaan

2017-02-01

Resistive switching in transition metal oxides involves intricate physical and chemical behaviours with potential for non-volatile memory and memristive devices. Although oxygen vacancy migration is known to play a crucial role in resistive switching of oxides, an in-depth understanding of oxygen vacancy-driven effects requires direct imaging of atomic-scale dynamic processes and their real-time impact on resistance changes. Here we use in situ transmission electron microscopy to demonstrate reversible switching between three resistance states in epitaxial La2/3Sr1/3MnO3 films. Simultaneous high-resolution imaging and resistance probing indicate that the switching events are caused by the formation of uniform structural phases. Reversible horizontal migration of oxygen vacancies within the manganite film, driven by combined effects of Joule heating and bias voltage, predominantly triggers the structural and resistive transitions. Our findings open prospects for ionotronic devices based on dynamic control of physical properties in complex oxide nanostructures.

Reversible susceptibility studies of magnetization switching in FeCoB synthetic antiferromagnets

NASA Astrophysics Data System (ADS)

Radu, Cosmin; Cimpoesu, Dorin; Girt, Erol; Ju, Ganping; Stancu, Alexandru; Spinu, Leonard

2007-05-01

In this paper we present a study of switching characteristics of a series of synthetic antiferromagnet (SAF) structures using reversible susceptibility experiments. Three series of SAF samples were considered in our study with (t1, t2), the thickness of the FeCoB layers of (80nm, 80nm), (50nm, 50nm), and (80nm, 20nm) and with the interlayer of Ru ranging from 0to2nm. A vector vibrating sample magnetometer was used to measure the hysteresis loops along the different directions in the plane of the samples. The reversible susceptibility experiments were performed using a resonant method based on a tunnel diode oscillator. We showed that the switching peaks in the susceptibility versus field plots obtained for different orientations of the applied dc field can be used to construct the switching diagram of the SAF structure. The critical curve constitutes the fingerprint of the switching behavior and provides information about micromagnetic and structural properties of SAF which is an essential component of modern magnetic random access memories.

Component processes in voluntary task switching.

PubMed

Demanet, Jelle; Liefooghe, Baptist

2014-05-01

The present study investigated the involvement of bottom-up and top-down control in task-switching situations in which tasks are selected on a voluntary basis. We tested for indices of both types of control in the reduction in switch cost that is observed when more time is available before executing a task. Participants had to indicate their task choice overtly prior to the actual task execution, and two time intervals were manipulated: the interval between the task-execution response of the previous trial and task-indication response of the current trial and the interval between task-indication response and task-execution response of a particular trial. In Experiment 1, the length of these intervals was manipulated orthogonally, and indices for top-down and bottom-up control were observed. Concerned with the validity of these results, Experiments 2-3 additionally discouraged participants from preparing the upcoming task before their task-indication response. Indices for bottom-up control remained, but not for top-down control. The characteristics of top-down and bottom-up control in voluntary task switching and task switching in general are discussed.

Anti-reflux surgery

MedlinePlus

... is connected to a video monitor in the operating room. Your surgeon does the repair while viewing the inside of your belly on the monitor. The surgeon may need to switch to an open procedure in case of problems. ENDOLUMINAL FUNDOPLICATION This is ...

Analogous selection processes in declarative and procedural working memory: N-2 list-repetition and task-repetition costs.

PubMed

Gade, Miriam; Souza, Alessandra S; Druey, Michel D; Oberauer, Klaus

2017-01-01

Working memory (WM) holds and manipulates representations for ongoing cognition. Oberauer (Psychology of Learning and Motivation, 51, 45-100, 2009) distinguishes between two analogous WM sub-systems: a declarative WM which handles the objects of thought, and a procedural WM which handles the representations of (cognitive) actions. Here, we assessed whether analogous effects are observed when participants switch between memory sets (declarative representations) and when they switch between task sets (procedural representations). One mechanism assumed to facilitate switching in procedural WM is the inhibition of previously used, but currently irrelevant task sets, as indexed by n-2 task-repetition costs (Mayr & Keele, Journal of Experimental Psychology: General, 129(1), 4-26, 2000). In this study we tested for an analogous effect in declarative WM. We assessed the evidence for n-2 list-repetition costs across eight experiments in which participants switched between memory lists to perform speeded classifications, mental arithmetic, or a local recognition test. N-2 list-repetition costs were obtained consistently in conditions assumed to increase interference between memory lists, and when lists formed chunks in long-term memory. Further analyses across experiments revealed a substantial contribution of episodic memory to n-2 list-repetition costs, thereby questioning the interpretation of n-2 repetition costs as reflecting inhibition. We reanalyzed the data of eight task-switching experiments, and observed that episodic memory also contributes to n-2 task-repetition costs. Taken together, these results show analogous processing principles in declarative and procedural WM, and question the relevance of inhibitory processes for efficient switching between mental sets.

A demonstration of direct access to colored stimuli following cueing by color.

PubMed

Navon, David; Kasten, Ronen

2011-09-01

To test whether cueing by color can affect orienting without first computing the location of the cued color, the impact of reorienting on the validity effect was examined. In Experiment 1 subjects were asked to detect a black dot target presented at random on either of two colored forms. The forms started being presented 750 ms before the onset of a central cue (either an arrow or a colored square). In some proportion of the trials the colors switched locations 150 ms after cue onset, simultaneously with target onset. The color switch was not found to retard responses following a color cue more than following a location cue. Furthermore, it did not reduce the validity effect of the color cue: Though the validity effect of the location cue was quite larger than the validity effect of the color cue, both effects were additive with the presence/absence of a color switch. In Experiment 2, subjects were rather asked to detect a change in shape of one of the colored forms. In this case, color switch was found to affect performance even less following a color cue. The fact that across experiments, color switch did not retard neither responding nor orienting selectively in the color cue condition, indicates that when attention is set to a certain color, reorienting to a new object following color switch does not require re-computing the address of the cued color. That finding is argued to embarrass a strong space-based view of visual attention. Copyright © 2011 Elsevier B.V. All rights reserved.

Trading off switch costs and stimulus availability benefits: An investigation of voluntary task-switching behavior in a predictable dynamic multitasking environment.

PubMed

Mittelstädt, Victor; Miller, Jeff; Kiesel, Andrea

2018-03-09

In the present study, we introduce a novel, self-organized task-switching paradigm that can be used to study more directly the determinants of switching. Instead of instructing participants to randomly switch between tasks, as in the classic voluntary task-switching paradigm (Arrington & Logan, 2004), we instructed participants to optimize their task performance in a voluntary task-switching environment in which the stimulus associated with the previously selected task appeared in each trial after a delay. Importantly, the stimulus onset asynchrony (SOA) increased further with each additional repetition of this task, whereas the stimulus needed for a task switch was always immediately available. We conducted two experiments with different SOA increments (i.e., Exp. 1a = 50 ms, Exp. 1b = 33 ms) to see whether this procedure would induce switching behavior, and we explored how people trade off switch costs against the increasing availability of the stimulus needed for a task repetition. We observed that participants adapted their behavior to the different task environments (i.e., SOA increments) and that participants switched tasks when the SOA in task switches approximately matched the switch costs. Moreover, correlational analyses indicated relations between individual switch costs and individual switch rates across participants. Together, these results demonstrate that participants were sensitive to the increased availability of switch stimuli in deciding whether to switch or to repeat, which in turn demonstrates flexible adaptive task selection behavior. We suggest that performance limitations in task switching interact with the task environment to influence switching behavior.

Towards Reproducibility in Computational Hydrology

NASA Astrophysics Data System (ADS)

Hutton, Christopher; Wagener, Thorsten; Freer, Jim; Han, Dawei; Duffy, Chris; Arheimer, Berit

2017-04-01

Reproducibility is a foundational principle in scientific research. The ability to independently re-run an experiment helps to verify the legitimacy of individual findings, and evolve (or reject) hypotheses and models of how environmental systems function, and move them from specific circumstances to more general theory. Yet in computational hydrology (and in environmental science more widely) the code and data that produces published results are not regularly made available, and even if they are made available, there remains a multitude of generally unreported choices that an individual scientist may have made that impact the study result. This situation strongly inhibits the ability of our community to reproduce and verify previous findings, as all the information and boundary conditions required to set up a computational experiment simply cannot be reported in an article's text alone. In Hutton et al 2016 [1], we argue that a cultural change is required in the computational hydrological community, in order to advance and make more robust the process of knowledge creation and hypothesis testing. We need to adopt common standards and infrastructures to: (1) make code readable and re-useable; (2) create well-documented workflows that combine re-useable code together with data to enable published scientific findings to be reproduced; (3) make code and workflows available, easy to find, and easy to interpret, using code and code metadata repositories. To create change we argue for improved graduate training in these areas. In this talk we reflect on our progress in achieving reproducible, open science in computational hydrology, which are relevant to the broader computational geoscience community. In particular, we draw on our experience in the Switch-On (EU funded) virtual water science laboratory (http://www.switch-on-vwsl.eu/participate/), which is an open platform for collaboration in hydrological experiments (e.g. [2]). While we use computational hydrology as the example application area, we believe that our conclusions are of value to the wider environmental and geoscience community as far as the use of code and models for scientific advancement is concerned. References: [1] Hutton, C., T. Wagener, J. Freer, D. Han, C. Duffy, and B. Arheimer (2016), Most computational hydrology is not reproducible, so is it really science?, Water Resour. Res., 52, 7548-7555, doi:10.1002/2016WR019285. [2] Ceola, S., et al. (2015), Virtual laboratories: New opportunities for collaborative water science, Hydrol. Earth Syst. Sci. Discuss., 11(12), 13443-13478, doi:10.5194/hessd-11-13443-2014.

Nicotiana tabacum as model for ozone - plant surface reactions

NASA Astrophysics Data System (ADS)

Jud, Werner; Fischer, Lukas; Wohlfahrt, Georg; Tissier, Alain; Canaval, Eva; Hansel, Armin

2015-04-01

Elevated tropospheric ozone concentrations are considered a toxic threat to plants, responsible for global crop losses with associated economic costs of several billion dollars per year. The ensuing injuries have been related to the uptake of ozone through the stomatal pores and oxidative effects damaging the internal leaf tissue. A striking question of current research is the environment and plant specific partitioning of ozone loss between gas phase, stomatal or plant surface sink terms. Here we show results from ozone fumigation experiments using various Nicotiana Tabacum varieties, whose surfaces are covered with different amounts of unsaturated diterpenoids exuded by their glandular trichomes. Exposure to elevated ozone levels (50 to 150 ppbv) for 5 to 15 hours in an exceptionally clean cuvette system did neither result in a reduction of photosynthesis nor caused any visible leaf damage. Both these ozone induced stress effects have been observed previously in ozone fumigation experiments with the ozone sensitive tobacco line Bel-W3. In our case ozone fumigation was accompanied by a continuous release of oxygenated volatile organic compounds, which could be clearly associated to their condensed phase precursors for the first time. Gas phase reactions of ozone were avoided by choosing a high enough gas exchange rate of the plant cuvette system. In the case of the Ambalema variety, that is known to exude only the diterpenoid cis-abienol, ozone fumigation experiments yield the volatiles formaldehyde and methyl vinyl ketone (MVK). The latter could be unequivocally separated from isomeric methacrolein (MACR) by the aid of a Selective Reagent Ion Time-of-Flight Mass Spectrometer (SRI-ToF-MS), which was switched every six minutes from H3O+ to NO+ primary ion mode and vice versa. Consistent with the picture of an ozone protection mechanism caused by reactive diterpenoids at the leaf surface are the results from dark-light experiments. The ozone loss obtained from the difference of ozone measured before and after the plant cuvette was investigated as a function of stomatal opening. Switching from dark to light conditions and thus opening the stomata only a small increase in ozone loss was observed for the Ambalema variety (25%). In the case of the 3H02 variety, a line known to emit almost no diterpenoids, the ozone loss increased by more than 100% when changing from dark to light conditions. It is anticipated that the described effect is of importance also for other plant species emitting low-volatility unsaturated organic compounds (e.g. in form of exudates or resins).

A Mechanical Switch Using Spectral Microshifts

NASA Astrophysics Data System (ADS)

Mitchell, Gordon L.; Saaski, Elric W.; Hartl, James C.

1989-02-01

Among the simplest fiber optic sensors, are those which operate in a binary fashion; they were the first sensor types to be developed. Early experiments with fiber bundles and shutters produced demonstrations of, for example, displacement sensors. Typical applications range from position sensing for aircraft landing gear to counting objects on a production line. Because they frequently replace electrical snap action switches, binary sensors are generally called optical switches. Optical switch applications account for a much larger market than the more complex analog measurements discussed in the balance of this volume. This paper presents an optical switch concept that uses a single fiber and is tolerant of back reflections. The sensor element is a low finesse Fabry-Perot pressure sensor which replaces the electrical contact in a conventional snap action switch.

Time Sharing Between Robotics and Process Control: Validating a Model of Attention Switching.

PubMed

Wickens, Christopher Dow; Gutzwiller, Robert S; Vieane, Alex; Clegg, Benjamin A; Sebok, Angelia; Janes, Jess

2016-03-01

The aim of this study was to validate the strategic task overload management (STOM) model that predicts task switching when concurrence is impossible. The STOM model predicts that in overload, tasks will be switched to, to the extent that they are attractive on task attributes of high priority, interest, and salience and low difficulty. But more-difficult tasks are less likely to be switched away from once they are being performed. In Experiment 1, participants performed four tasks of the Multi-Attribute Task Battery and provided task-switching data to inform the role of difficulty and priority. In Experiment 2, participants concurrently performed an environmental control task and a robotic arm simulation. Workload was varied by automation of arm movement and both the phases of environmental control and existence of decision support for fault management. Attention to the two tasks was measured using a head tracker. Experiment 1 revealed the lack of influence of task priority and confirmed the differing roles of task difficulty. In Experiment 2, the percentage attention allocation across the eight conditions was predicted by the STOM model when participants rated the four attributes. Model predictions were compared against empirical data and accounted for over 95% of variance in task allocation. More-difficult tasks were performed longer than easier tasks. Task priority does not influence allocation. The multiattribute decision model provided a good fit to the data. The STOM model is useful for predicting cognitive tunneling given that human-in-the-loop simulation is time-consuming and expensive. © 2016, Human Factors and Ergonomics Society.

Exploration of adherence and patient experiences with DOACs one year after switching from vitamin-K antagonists- insights from the switching study.

PubMed

Bartoli-Abdou, John K; Patel, Jignesh P; Crawshaw, Jacob; Vadher, Bipin; Brown, Alison; Roberts, Lara N; Patel, Raj K; Arya, Roopen; Auyeung, Vivian

2018-02-01

Current UK and European guidelines recommend anticoagulated patients prescribed warfarin with time in therapeutic range (TTR) <65% be considered for DOAC therapy. There has been considerable concern that adherence with DOACs may be poor compared with warfarin. Little is known about the patient experience of switching from warfarin to DOAC and how patients manage their DOAC long term. Our aim was to conduct focus groups exploring patient's previous experiences with warfarin, their current experience with DOACs, their adherence to DOACs and the long-term service provision they envisage. Patients enrolled on the Switching Study who had been switched from warfarin to a DOAC >1year previously were invited to participate in focus groups. Two focus groups for atrial fibrillation (AF) and two for secondary prevention of venous thromboembolism (VTE) patients were held at anticoagulation clinics in South London, UK. Data was analysed using framework analysis to extract dominant themes. Five VTE patients and 15 AF patients attended the focus groups. Dominant themes that emerged were: indication specific anticoagulation prioritisation, warfarin as a necessary inconvenience, DOACs as the anticoagulant of choice, concerns regarding DOAC monitoring, high adherence to DOACs and desire for long-term access to specialist anticoagulation services. VTE patients prioritised anticoagulation over other therapies whereas AF patients did not. All participants reported high levels of adherence to DOACs. Patients derived confidence from long-term management in specialist anticoagulation clinics stating a preference to be managed in such a service. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Shifting Attention Between Visual Dimensions as a Source of Switch Costs.

PubMed

Elchlepp, Heike; Best, Maisy; Lavric, Aureliu; Monsell, Stephen

2017-04-01

Task-switching experiments have documented a puzzling phenomenon: Advance warning of the switch reduces but does not eliminate the switch cost. Theoretical accounts have posited that the residual switch cost arises when one selects the relevant stimulus-response mapping, leaving earlier perceptual processes unaffected. We put this assumption to the test by seeking electrophysiological markers of encoding a perceptual dimension. Participants categorized a colored letter as a vowel or consonant or its color as "warm" or "cold." Orthogonally to the color manipulation, some colors were eight times more frequent than others, and the letters were in upper- or lowercase. Color frequency modulated the electroencephalogram amplitude at around 150 ms when participants repeated the color-classification task. When participants switched from the letter task to the color task, this effect was significantly delayed. Thus, even when prepared for, a task switch delays or prolongs encoding of the relevant perceptual dimension.

Dynamics of phenotypic switching of bacterial cells with temporal fluctuations in pressure

NASA Astrophysics Data System (ADS)

Nepal, Sudip; Kumar, Pradeep

2018-05-01

Phenotypic switching is one of the mechanisms by which bacteria thrive in ever changing environmental conditions around them. Earlier studies have shown that the application of steady high hydrostatic pressure leads to stochastic switching of mesophilic bacteria from a cellular phenotype having a normal cell cycle to another phenotype lacking cell division. Here, we have studied the dynamics of this phenotypic switching with fluctuating periodic pressure using a set of experiments and a theoretical model. Our results suggest that the phenotypic switching rate from high-pressure phenotype to low-pressure phenotype in the reversible regime is larger as compared to the switching rate from low-pressure phenotype to high-pressure phenotype. Furthermore, we find that even though the cell division and elongation are presumably regulated by a large number of genes the underlying physics of the dynamics of stochastic switching at high pressure is captured reasonably well by a simple two-state model.

Decomposing task-switching costs with the diffusion model.

PubMed

Schmitz, Florian; Voss, Andreas

2012-02-01

In four experiments, task-switching processes were investigated with variants of the alternating runs paradigm and the explicit cueing paradigm. The classical diffusion model for binary decisions (Ratcliff, 1978) was used to dissociate different components of task-switching costs. Findings can be reconciled with the view that task-switching processes take place in successive phases as postulated by multiple-components models of task switching (e.g., Mayr & Kliegl, 2003; Ruthruff, Remington, & Johnston, 2001). At an earlier phase, task-set reconfiguration (Rogers & Monsell, 1995) or cue-encoding (Schneider & Logan, 2005) takes place, at a later phase, the response is selected in accord with constraints set in the first phase. Inertia effects (Allport, Styles, & Hsieh, 1994; Allport & Wylie, 2000) were shown to affect this later stage. Additionally, findings support the notion that response caution contributes to both global as well as to local switching costs when task switches are predictable.

Underlying thermodynamics of pH-dependent allostery.

PubMed

Di Russo, Natali V; Martí, Marcelo A; Roitberg, Adrian E

2014-11-13

Understanding the effects of coupling protein protonation and conformational states is critical to the development of drugs targeting pH sensors and to the rational engineering of pH switches. In this work, we address this issue by performing a comprehensive study of the pH-regulated switch from the closed to the open conformation in nitrophorin 4 (NP4) that determines its pH-dependent activity. Our calculations show that D30 is the only amino acid that has two significantly different pKas in the open and closed conformations, confirming its critical role in regulating pH-dependent behavior. In addition, we describe the free-energy landscape of the conformational change as a function of pH, obtaining accurate estimations of free-energy barriers and equilibrium constants using different methods. The underlying thermodynamic model of the switch workings suggests the possibility of tuning the observed pKa only through the conformational equilibria, keeping the same conformation-specific pKas, as evidenced by the proposed K125L mutant. Moreover, coupling between the protonation and conformational equilibria results in efficient regulation and pH-sensing around physiological pH values only for some combinations of protonation and conformational equilibrium constants, placing constraints on their possible values and leaving a narrow space for protein molecular evolution. The calculations and analysis presented here are of general applicability and provide a guide as to how more complex systems can be studied, offering insight into how pH-regulated allostery works of great value for designing drugs that target pH sensors and for rational engineering of pH switches beyond the common histidine trigger.

Simulation of the Plasma Afterglow in the Discharge Gap of a Subnanosecond Switch Based on an Open Discharge in Helium

NASA Astrophysics Data System (ADS)

Alexandrov, A. L.; Schweigert, I. V.

2018-05-01

The phenomenon of subnanosecond electrical breakdown in a strong electric field observed in an open discharge in helium at pressures of 6-20 Torr can be used to create ultrafast plasma switches triggering into a conducting state for a time shorter than 1 ns. To evaluate the possible repetition rate of such a subnanosecond switch, it is interesting to study the decay dynamics of the plasma remaining in the discharge gap after ultrafast breakdown. In this paper, a kinetic model based on the particle-in-cell Monte Carlo collision method is used to study the dynamics of the plasma afterglow in the discharge gap of a subnanosecond switch operating with helium at a pressure of 6 Torr. The simulation results show that the radiative, collisional-radiative, and three-body collision recombination mechanisms significantly contribute to the afterglow decay only while the plasma density remains higher than 1012 cm-3; the main mechanism of the further plasma decay is diffusion of plasma particles onto the wall. Therefore, the effect of recombination in the plasma bulk is observed only during the first 10-20 μs of the afterglow. Over nearly the same time, plasma electrons become thermalized. The afterglow time can be substantially reduced by applying a positive voltage U c to the cathode. Since diffusive losses are limited by the ion mobility, the additional ion drift toward the wall significantly accelerates plasma decay. As U c increases from 0 to +500 V, the characteristic time of plasma decay is reduced from 35 to 10 μs.

Interpreting instructional cues in task switching procedures: the role of mediator retrieval.

PubMed

Logan, Gordon D; Schneider, Darryl W

2006-03-01

In 3 experiments the role of mediators in task switching with transparent and nontransparent cues was examined. Subjects switched between magnitude (greater or less than 5) and parity (odd or even) judgments of single digits. A cue-target congruency effect indicated mediator use: subjects responded faster to congruent cue-target combinations (e.g., ODD-3) than to incongruent cue-target combinations (e.g., ODD-4). Experiment 1 revealed significant congruency effects with transparent word cues (ODD, EVEN, HIGH, and LOW) and with relatively transparent letter cues (O, E, H, and L) but not with nontransparent letter cues (D, V, G, and W). Experiment 2 revealed significant congruency effects after subjects who were trained with nontransparent letter cues were informed of the relations between cues and word mediators halfway through the experiment. Experiment 3 showed that congruency effects with relatively transparent letter cues diminished over 10 sessions of practice, suggesting that subjects used mediators less as practice progressed. The results are discussed in terms of the role of mediators in interpreting instructional cues.

Improved body weight and metabolic outcomes in overweight or obese psychiatric patients switched to amisulpride from other atypical antipsychotics.

PubMed

Lin, Chao-Cheng; Bai, Ya-Mei; Wang, Ying-Chieh; Chen, Tzu-Ting; Lai, I-Ching; Chen, Jen-Yeu; Chen, Shiow-Yi; Gau, Susan S F; Liou, Ying-Jay

2009-12-01

Switching to a different second-generation antipsychotic (SGA) with a lower risk of weight gain is recommended for overweight or obese psychiatric patients undergoing SGA treatment. However, there have been no complete reports regarding the long-term metabolic effects of switching to amisulpride. In this open-label 1-year study, we investigated the effects on body weight and other metabolic profiles when psychiatric patients treated with another SGA were switched to amisulpride treatment. Forty-six schizophrenia or schizoaffective inpatients with a body mass index greater than 27 kg/m were enrolled in the switch group. These patients were cross-titrated to amisulpride treatment and followed up for 1 year prospectively. Another 46 inpatients matched with the baseline body mass index of those in the switch group were enrolled as the control group retrospectively. The results showed that the switch group had greater weight loss than the control group (7.80 +/- 6.67 vs 2.60 +/- 6.23 kg, respectively; repeated-measure analysis of variance, P < 0.0005). During the treatment course, the amisulpride-treated patients showed significantly decreased fasting triglyceride, total cholesterol, glucose, and insulin resistance levels; decreased diastolic blood pressure and pulse rate; and a significant increase in high-density lipoprotein cholesterol levels after switching to amisulpride (all with a P < 0.05). The prevalence of metabolic syndrome in amisulpride-treated patients also decreased significantly from 65.2% to 30.4% (McNemar test, P < 0.0005). These findings suggest that switching to amisulpride could be an effective treatment of overweight or obese psychiatric patients treated previously with other SGAs.

An improved fault-tolerant control scheme for PWM inverter-fed induction motor-based EVs.

PubMed

Tabbache, Bekheïra; Benbouzid, Mohamed; Kheloui, Abdelaziz; Bourgeot, Jean-Matthieu; Mamoune, Abdeslam

2013-11-01

This paper proposes an improved fault-tolerant control scheme for PWM inverter-fed induction motor-based electric vehicles. The proposed strategy deals with power switch (IGBTs) failures mitigation within a reconfigurable induction motor control. To increase the vehicle powertrain reliability regarding IGBT open-circuit failures, 4-wire and 4-leg PWM inverter topologies are investigated and their performances discussed in a vehicle context. The proposed fault-tolerant topologies require only minimum hardware modifications to the conventional off-the-shelf six-switch three-phase drive, mitigating the IGBTs failures by specific inverter control. Indeed, the two topologies exploit the induction motor neutral accessibility for fault-tolerant purposes. The 4-wire topology uses then classical hysteresis controllers to account for the IGBT failures. The 4-leg topology, meanwhile, uses a specific 3D space vector PWM to handle vehicle requirements in terms of size (DC bus capacitors) and cost (IGBTs number). Experiments on an induction motor drive and simulations on an electric vehicle are carried-out using a European urban driving cycle to show that the proposed fault-tolerant control approach is effective and provides a simple configuration with high performance in terms of speed and torque responses. Copyright © 2013 ISA. Published by Elsevier Ltd. All rights reserved.

Long-term efficacy and tolerability of quetiapine in patients with schizophrenia who switched from other antipsychotics because of inadequate therapeutic response-a prospective open-label study.

PubMed

Hashimoto, Naoki; Toyomaki, Atsuhito; Honda, Minoru; Miyano, Satoru; Nitta, Nobuyuki; Sawayama, Hiroyuki; Sugawara, Yasufumi; Uemura, Keiichi; Tsukamoto, Noriko; Koyama, Tsukasa; Kusumi, Ichiro

2015-01-01

While the frequency and importance of antipsychotic switching in patients with schizophrenia, there is insufficient evidence with regard to switching strategy. Quetiapine is one of the drugs of choice for switch because of its unique receptor profile. However, there were no data on the long-term clinical and neurocognitive effect of quetiapine in patients who had responded inadequately to prior antipsychotics. The purpose of this study is to examine the long-term efficacy and tolerability of quetiapine in patients with schizophrenia who switched from other antipsychotics because of inadequate therapeutic response. We hypothesized that quetiapine would show long-term effectiveness in broad symptom dimensions including negative and neurocognitive symptoms while having good tolerability. Twenty-nine subjects with schizophrenia who did not respond to their current monotherapy of antipsychotic or who could not tolerate the treatment were switched to quetiapine and assessed at baseline and at 3, 6, and 12 months. The outcome measures included the brief assessment of cognition in schizophrenia (BACS), the Positive and Negative Syndrome Scale (PANSS), the Clinical Global Impressions Scale (CGI), the Schizophrenia Quality of Life Scale Japanese version (JSQLS), the Athens Insomnia Scale (AIS), and the Drug Attitude Inventory with 30 items (DAI-30). The Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS), HbA1c, prolactin (PRL), and body weight were also evaluated. Statistically significant improvements were observed in all subscores of the PANSS, the GAF, and the symptoms and side effects subscale of the JSQLS, the DIEPSS, the AIS, and the PRL level, and nearly significant improvements were observed in the DAI-30. Quetiapine monotherapy was associated with significant improvement in the verbal memory test, even after controlling for the practice effect. Although quetiapine was well tolerated, three subjects dropped out because of the worsening of the psychotic symptoms and two additional subjects dropped out because of somnolence. In this open-label, single-arm study of 29 patients, quetiapine improved both the clinical symptoms and the neurocognitive impairment in chronic schizophrenia patients who failed to respond to prior antipsychotic treatment.

Research on the electromagnetic radiation characteristics of the gas main switch of a capacitive intense electron-beam accelerator

NASA Astrophysics Data System (ADS)

Qiu, Yongfeng; Liu, Jinliang; Yang, Jianhua; Cheng, Xinbing; Li, Guolin

2017-11-01

Strong electromagnetic fields are radiated during the operation of the intense electron-beam accelerator (IEBA), which may lead to the nearby electronic devices out of order. In this paper, the research on the electromagnetic radiation characteristic of the gas main switch of a capacitive IEBA is carried out by the methods of theory analysis and experiment investigation. It is obtained that the gas main switch is the dominating radiation resource. In the absence of electromagnetic shielding for the gas main switch, when the pulse forming line of the IEBA is charged to 700 kV, the radiation field with amplitude of 3280 V/m, dominant frequency of 84 MHz and high frequency 100 MHz is obtained at a distance of 10 meters away from the gas main switch. The experimental results of the radiation field agree with the theoretical calculations. We analyze the achievements of several research groups and find that there is a relationship between the rise time (T) of the transient current of the gas main switch and the dominant frequency (F) of the radiation field, namely, F*T=1. Contrast experiment is carried out with a metal shield cover for the gas main switch. Experimental results show that for the shielded setup the radiation field reduces to 115 V/m, the dominant frequency increases to 86.5 MHz at a distance of 10 away meters from the gas main switch. These conclusions are beneficial for further research on the electromagnetic radiation and protection of the IEBA.

Multistage switching hardware and software implementations for student experiment purpose

NASA Astrophysics Data System (ADS)

Sani, A.; Suherman

2018-02-01

Current communication and internet networks are underpinned by the switching technologies that interconnect one network to the others. Students’ understanding on networks rely on how they conver the theories. However, understanding theories without touching the reality may exert spots in the overall knowledge. This paper reports the progress of the multistage switching design and implementation for student laboratory activities. The hardware and software designs are based on three stages clos switching architecture with modular 2x2 switches, controlled by an arduino microcontroller. The designed modules can also be extended for batcher and bayan switch, and working on circuit and packet switching systems. The circuit analysis and simulation show that the blocking probability for each switch combinations can be obtained by generating random or patterned traffics. The mathematic model and simulation analysis shows 16.4% blocking probability differences as the traffic generation is uniform. The circuits design components and interfacing solution have been identified to allow next step implementation.

Copper atomic-scale transistors

PubMed Central

Kavalenka, Maryna N; Röger, Moritz; Albrecht, Daniel; Hölscher, Hendrik; Leuthold, Jürgen

2017-01-01

We investigated copper as a working material for metallic atomic-scale transistors and confirmed that copper atomic-scale transistors can be fabricated and operated electrochemically in a copper electrolyte (CuSO4 + H2SO4) in bi-distilled water under ambient conditions with three microelectrodes (source, drain and gate). The electrochemical switching-on potential of the atomic-scale transistor is below 350 mV, and the switching-off potential is between 0 and −170 mV. The switching-on current is above 1 μA, which is compatible with semiconductor transistor devices. Both sign and amplitude of the voltage applied across the source and drain electrodes (U bias) influence the switching rate of the transistor and the copper deposition on the electrodes, and correspondingly shift the electrochemical operation potential. The copper atomic-scale transistors can be switched using a function generator without a computer-controlled feedback switching mechanism. The copper atomic-scale transistors, with only one or two atoms at the narrowest constriction, were realized to switch between 0 and 1G 0 (G 0 = 2e2/h; with e being the electron charge, and h being Planck’s constant) or 2G 0 by the function generator. The switching rate can reach up to 10 Hz. The copper atomic-scale transistor demonstrates volatile/non-volatile dual functionalities. Such an optimal merging of the logic with memory may open a perspective for processor-in-memory and logic-in-memory architectures, using copper as an alternative working material besides silver for fully metallic atomic-scale transistors. PMID:28382242

Effect of laser beam conditioning on fabrication of clean micro-channel on stainless steel 316L using second harmonic of Q-switched Nd:YAG laser

NASA Astrophysics Data System (ADS)

Singh, Sanasam Sunderlal; Baruah, Prahlad Kr; Khare, Alika; Joshi, Shrikrishna N.

2018-02-01

Laser micromachining of metals for fabrication of micro-channels generate ridge formation along the edges accompanied by ripples along the channel bed. The ridge formation is due to the formation of interference pattern formed by back reflections from the beam splitter and other optical components involved before focusing on the work piece. This problem can be curtailed by using a suitable aperture or Iris diaphragm so as to cut the unwanted portion of the laser beam before illuminating the sample. This paper reports an experimental investigation on minimizing this problem by conditioning the laser beam using an Iris diaphragm and using optimum process parameters. In this work, systematic experiments have been carried out using the second harmonic of a Q-switched Nd:YAG laser to fabricate micro-channels. Initial experiments revealed that formation of ridges along the sides of micro-channel can easily be minimized with the help of Iris diaphragm. Further it is noted that a clean micro-channel of depth 43.39 μm, width up to 64.49 μm and of good surface quality with average surface roughness (Ra) value of 370 nm can be machined on stainless steel (SS) 316L by employing optimum process condition: laser beam energy of 30 mJ/pulse, 11 number of laser scans and scan speed of 169.54 μm/s with an opening of 4 mm diameter of Iris diaphragm in the path of the laser beam.

Alleviating line overload by line switching

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, H.E.

1988-01-01

Traditionally, the method used by power system dispatchers to reduce or to eliminate line overload conditions has been to shift generation. Such shifts are generally in conflict with the carefully considered economic dispatch of generation. A proper generation schedule has taken into account many factors, such as generator limits, transmission penalties, incremental costs, var support, and system security. Any deviation from this schedule results in increased production cost. Recently, consideration has been given to alleviating line overloads by line switching. In many situations, line switching does not greatly change the transmission penalty factors and, therefore, can be undertaken without seriouslymore » affecting the economic dispatch. It would be convenient for system operators to have a fast, easy-to-operate computer and program available for the evaluation of the efficacy of a line removal (or addition) in dealing with an overload. It is imperative that the operator be properly advised, that a certain line switching reduces the overload and not aggravate the condition. After it has been determined that a line opening (or closing) produces the desired effect, the operator still must assess the consequence of such switching on system security before actually taking such action.« less

Three-dimensional resistivity and switching between correlated electronic states in 1T-TaS2

NASA Astrophysics Data System (ADS)

Svetin, Damjan; Vaskivskyi, Igor; Brazovskii, Serguei; Mihailovic, Dragan

2017-04-01

Recent demonstrations of controlled switching between different ordered macroscopic states by impulsive electromagnetic perturbations in complex materials have opened some fundamental questions on the mechanisms responsible for such remarkable behavior. Here we experimentally address the question of whether two-dimensional (2D) Mott physics can be responsible for unusual switching between states of different electronic order in the layered dichalcogenide 1T-TaS2, or it is a result of subtle inter-layer “orbitronic” re-ordering of its stacking structure. We report on in-plane (IP) and out-of-plane (OP) resistance switching by current-pulse injection at low temperatures. Elucidating the controversial theoretical predictions, we also report on measurements of the anisotropy of the electrical resistivity below room temperature. From the T-dependence of ρ⊥ and ρ||, we surmise that the resistivity is more consistent with collective motion than single particle diffusive or band-like transport. The relaxation dynamics of the metastable state for both IP and OP electron transport are seemingly governed by the same mesoscopic quantum re-ordering process. We conclude that 1T-TaS2 shows resistance switching arising from an interplay of both IP and OP correlations.

Investigation of Thermal Management and Metamaterials

DTIC Science & Technology

2010-03-01

create a metasurface (a 2-D metamaterial). This metasurface could have variable electrical and thermal conductivity via switching (opening/closing) of...selected for AFIT’s first thermal metamaterial design. The first potential application of this metasurface includes use as a thin film (less

High-speed optical switch fabrics with large port count.

PubMed

Yeo, Yong-Kee; Xu, Zhaowen; Wang, Dawei; Liu, Jianguo; Wang, Yixin; Cheng, Tee-Hiang

2009-06-22

We report a novel architecture that can be used to construct optical switch fabrics with very high port count and nanoseconds switching speed. It is well known that optical switch fabrics with very fast switching time and high port count are challenging to realize. Currently, one of the most promising solutions is based on a combination of wavelength-tunable lasers and the arrayed waveguide grating router (AWGR). To scale up the number of ports in such switches, a direct method is to use AWGRs with a high channel count. However, such AWGRs introduce very large crosstalk noise due to the close wavelength channel spacing. In this paper, we propose an architecture for realizing a high-port count optical switch fabric using a combination of low-port count AWGRs, optical ON-OFF gates and WDM couplers. Using this new methodology, we constructed a proof-of concept experiment to demonstrate the feasibility of a 256 x 256 optical switch fabric. To our knowledge, this port count is the highest ever reported for switch fabrics of this type.

Hand preference and skilled hand performance among individuals with successful rightward conversions of the writing hand.

PubMed

Porac, Clare

2009-03-01

Searleman and Porac (2001) studied lateral preference patterns among successfully switched left-hand writers, left-hand writers with no switch pressure history, and left-hand writers who did not switch when pressured. They concluded that left-handers who successfully shift to right-hand writing are following an inherent right-sided lateralisation pattern that they already possess. Searleman and Porac suggested that the neural mechanisms that control lateralisation in the successfully switched individuals are systematically different from those of other groups of left-handers. I examined patterns of skilled and less-skilled hand preference and skilled hand performance in a sample of 394 adults (ages 18-94 years). The sample contained successfully switched left-hand writers, left-handers pressured to shift who remained left-hand writers, left-handers who did not experience shift pressures, and right-handers. Both skilled hand preference and skilled hand performance were shifted towards the right side in successfully switched left-hand writers. This group also displayed mixed patterns of hand preference and skilled hand performance in that they were not as right-sided as "natural" right-handers nor were they as left-sided as the two left-hand writing groups, which did not differ from each other. The experience of being pressured to switch to right-hand writing was not sufficient to shift lateralisation patterns; the pressures must be experienced in the context of an underlying neural control mechanism that is amenable to change as a result of these external influences.

Inhibition, interference, and conflict in task switching.

PubMed

Costa, Russell E; Friedrich, Frances J

2012-12-01

The role of inhibition in the task-switching process has received increased empirical and theoretical attention in the literature on cognitive control. Many accounts have suggested that inhibition occurs when a conflict must be resolved-for example, when a target stimulus contains features of more than one task. In the two experiments reported here, we used variants of backward inhibition, or N - 2 repetition, designs to examine (1) whether inhibition occurs in the absence of conflict at the stimulus or response level, (2) when in the task-switching process such inhibition may occur, and (3) the potential consequences of inhibition. In Experiment 1, we demonstrate that neither stimulus- nor response-level conflict is necessary for inhibition to occur, while the results of Experiment 2 suggest that inhibition may be associated with a reduction of proactive interference (PI) from a previously performed task. Evidence of inhibition and the reduction of PI both occurred at the task-set level. However, inhibition of specific stimulus values can also occur, but this is clearly separable from task-set inhibition. Both experiments also provided evidence that task-set inhibition can be applied at the time of the new task cue, as opposed to at the onset of the target or at the response stage of the trial. Taken together, the results from these experiments provide insight into when and where in the task-switching process inhibition may occur, as well as into the potential functional benefits that inhibition of task sets may provide.

MSiReader v1.0: Evolving Open-Source Mass Spectrometry Imaging Software for Targeted and Untargeted Analyses

NASA Astrophysics Data System (ADS)

Bokhart, Mark T.; Nazari, Milad; Garrard, Kenneth P.; Muddiman, David C.

2018-01-01

A major update to the mass spectrometry imaging (MSI) software MSiReader is presented, offering a multitude of newly added features critical to MSI analyses. MSiReader is a free, open-source, and vendor-neutral software written in the MATLAB platform and is capable of analyzing most common MSI data formats. A standalone version of the software, which does not require a MATLAB license, is also distributed. The newly incorporated data analysis features expand the utility of MSiReader beyond simple visualization of molecular distributions. The MSiQuantification tool allows researchers to calculate absolute concentrations from quantification MSI experiments exclusively through MSiReader software, significantly reducing data analysis time. An image overlay feature allows the incorporation of complementary imaging modalities to be displayed with the MSI data. A polarity filter has also been incorporated into the data loading step, allowing the facile analysis of polarity switching experiments without the need for data parsing prior to loading the data file into MSiReader. A quality assurance feature to generate a mass measurement accuracy (MMA) heatmap for an analyte of interest has also been added to allow for the investigation of MMA across the imaging experiment. Most importantly, as new features have been added performance has not degraded, in fact it has been dramatically improved. These new tools and the improvements to the performance in MSiReader v1.0 enable the MSI community to evaluate their data in greater depth and in less time. [Figure not available: see fulltext.

Transport dynamics of molecular motors that switch between an active and inactive state

NASA Astrophysics Data System (ADS)

Pinkoviezky, I.; Gov, N. S.

2013-08-01

Molecular motors are involved in key transport processes in the cell. Many of these motors can switch from an active to a nonactive state, either spontaneously or depending on their interaction with other molecules. When active, the motors move processively along the filaments, while when inactive they are stationary. We treat here the simple case of spontaneously switching motors, between the active and inactive states, along an open linear track. We use our recent analogy with vehicular traffic, where we go beyond the mean-field description. We map the phase diagram of this system, and find that it clearly breaks the symmetry between the different phases, as compared to the standard total asymmetric exclusion process. We make several predictions that may be testable using molecular motors in vitro and in living cells.

Combustion mode switching with a turbocharged/supercharged engine

DOEpatents

Mond, Alan; Jiang, Li

2015-09-22

A method for switching between low- and high-dilution combustion modes in an internal combustion engine having an intake passage with an exhaust-driven turbocharger, a crankshaft-driven positive displacement supercharger downstream of the turbocharger and having variable boost controllable with a supercharger bypass valve, and a throttle valve downstream of the supercharger. The current combustion mode and mass air flow are determined. A switch to the target combustion mode is commanded when an operating condition falls within a range of predetermined operating conditions. A target mass air flow to achieve a target air-fuel ratio corresponding to the current operating condition and the target combustion mode is determined. The degree of opening of the supercharger bypass valve and the throttle valve are controlled to achieve the target mass air flow. The amount of residual exhaust gas is manipulated.

Ultrasonic unipolar pulse/echo instrument

DOEpatents

Hughes, M.J.; Hsu, D.K.; Thompson, D.O.; Wormley, S.J.

1993-04-06

An ultrasonic unipolar pulse/echo instrument uses active switches and a timing and drive circuitry to control electrical energy to a transducer, the discharging of the transducer, and the opening of an electrical pathway to the receiving circuitry for the returning echoes. The active switches utilize MOSFET devices along with decoupling circuitry to insure the preservation of the unipolar nature of the pulses, insure fast transition times, and maintain broad band width and time resolution. A housing contains the various circuitry and switches and allows connection to a power supply and a movable ultrasonic transducer. The circuitry maintains low impedance input to the transducer during transmitting cycles, and high impedance between the transducer and the receiving circuit during receive cycles to maintain the unipolar pulse shape. A unipolar pulse is valuable for nondestructive evaluation, a prime use for the present instrument.

Ultrasonic unipolar pulse/echo instrument

DOEpatents

Hughes, Michael S.; Hsu, David K.; Thompson, Donald O.; Wormley, Samuel J.

1993-01-01

An ultrasonic unipolar pulse/echo instrument uses active switches and a timing and drive circuitry to control electrical energy to a transducer, the discharging of the transducer, and the opening of an electrical pathway to the receiving circuitry for the returning echoes. The active switches utilize MOSFET devices along with decoupling circuitry to insure the preservation of the unipolar nature of the pulses, insure fast transition times, and maintain broad band width and time resolution. A housing contains the various circuitry and switches and allows connection to a power supply and a movable ultrasonic transducer. The circuitry maintains low impedance input to the transducer during transmitting cycles, and high impedance between the transducer and the receiving circuit during receive cycles to maintain the unipolar pulse shape. A unipolar pulse is valuable for nondestructive evaluation, a prime use for the present instrument.

Resistive switching behaviors of Au/pentacene/Si-nanowire arrays/heavily doped n-type Si devices for memory applications

NASA Astrophysics Data System (ADS)

Tsao, Hou-Yen; Lin, Yow-Jon

2014-02-01

The fabrication of memory devices based on the Au/pentacene/heavily doped n-type Si (n+-Si), Au/pentacene/Si nanowires (SiNWs)/n+-Si, and Au/pentacene/H2O2-treated SiNWs/n+-Si structures and their resistive switching characteristics were reported. A pentacene memory structure using SiNW arrays as charge storage nodes was demonstrated. The Au/pentacene/SiNWs/n+-Si devices show hysteresis behavior. H2O2 treatment may lead to the hysteresis degradation. However, no hysteresis-type current-voltage characteristics were observed for Au/pentacene/n+-Si devices, indicating that the resistive switching characteristic is sensitive to SiNWs and the charge trapping effect originates from SiNWs. The concept of nanowires within the organic layer opens a promising direction for organic memory devices.

Investigation of high-voltage pulse trigger generator based on photo-conductive semiconductor switch

NASA Astrophysics Data System (ADS)

Chu, Xu; Liu, Jin-Liang; Wang, Lang-Ning; Qiu, Yong-Feng

2018-06-01

The trigger to generate high-voltage pulse is one of the most important parts in a pulsed-power system, especially for the conduction characteristics of the main switch. However, traditional triggers usually have the drawbacks of large structure and worse long-term working stability, which goes against the demands of pulsed-power system miniaturization and stability. In the paper, a pulse trigger using photo-conductive semiconductor switch was developed, which is of small size, stable performance and steep leading edge of the output pulse rise. It is found that the output trigger pulse rise time is 14 ns, and the jitter of 20 shots is 330 ps. Applying the designed pulsed trigger in a field distortion switch and a triggered vacuum switch, experiments show that the switches could be triggered stably with reduced jitter.

Zero-voltage DC/DC converter with asymmetric pulse-width modulation for DC micro-grid system

NASA Astrophysics Data System (ADS)

Lin, Bor-Ren

2018-04-01

This paper presents a zero-voltage switching DC/DC converter for DC micro-grid system applications. The proposed circuit includes three half-bridge circuit cells connected in primary-series and secondary-parallel in order to lessen the voltage rating of power switches and current rating of rectifier diodes. Thus, low voltage stress of power MOSFETs can be adopted for high-voltage input applications with high switching frequency operation. In order to achieve low switching losses and high circuit efficiency, asymmetric pulse-width modulation is used to turn on power switches at zero voltage. Flying capacitors are used between each circuit cell to automatically balance input split voltages. Therefore, the voltage stress of each power switch is limited at Vin/3. Finally, a prototype is constructed and experiments are provided to demonstrate the circuit performance.

Design criteria monograph for actuators and operators

NASA Technical Reports Server (NTRS)

1974-01-01

Instrumentation for actuators and operators includes electrical position-indicating switches, potentiometers, and transducers and pressure-indicating switches and transducers. Monograph is based on critical evaluation of experiences and practices in design, test, and use of these control devices and instruments in operational space vehicles.

49 CFR 236.60 - Switch shunting circuit; use restricted.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and... circuit shall not be hereafter installed, except where tract or control circuit is opened by the circuit controller. [49 FR 3384, Jan. 26, 1984] Wires and Cables ...

49 CFR 236.60 - Switch shunting circuit; use restricted.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and... circuit shall not be hereafter installed, except where tract or control circuit is opened by the circuit controller. [49 FR 3384, Jan. 26, 1984] Wires and Cables ...

49 CFR 236.60 - Switch shunting circuit; use restricted.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and... circuit shall not be hereafter installed, except where tract or control circuit is opened by the circuit controller. [49 FR 3384, Jan. 26, 1984] Wires and Cables ...

49 CFR 236.60 - Switch shunting circuit; use restricted.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and... circuit shall not be hereafter installed, except where tract or control circuit is opened by the circuit controller. [49 FR 3384, Jan. 26, 1984] Wires and Cables ...

49 CFR 236.60 - Switch shunting circuit; use restricted.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES Rules and... circuit shall not be hereafter installed, except where tract or control circuit is opened by the circuit controller. [49 FR 3384, Jan. 26, 1984] Wires and Cables ...

Self-learning ability realized with a resistive switching device based on a Ni-rich nickel oxide thin film

NASA Astrophysics Data System (ADS)

Liu, Y.; Chen, T. P.; Liu, Z.; Yu, Y. F.; Yu, Q.; Li, P.; Fung, S.

2011-12-01

The resistive switching device based on a Ni-rich nickel oxide thin film exhibits an inherent learning ability of a neural network. The device has the short-term-memory and long-term-memory functions analogous to those of the human brain, depending on the history of its experience of voltage pulsing or sweeping. Neuroplasticity could be realized with the device, as the device can be switched from a high-resistance state to a low-resistance state due to the formation of stable filaments by a series of electrical pulses, resembling the changes such as the growth of new connections and the creation of new neurons in the brain in response to experience.