Sample records for observed switching mechanism

  1. Micro electro mechanical system optical switching

    DOE Patents [OSTI]

    Thorson, Kevin J; Stevens, Rick C; Kryzak, Charles J; Leininger, Brian S; Kornrumpf, William P; Forman, Glenn A; Iannotti, Joseph A; Spahn, Olga B; Cowan, William D; Dagel, Daryl J

    2013-12-17T23:59:59.000Z

    The present disclosure includes apparatus, system, and method embodiments that provide micro electo mechanical system optical switching and methods of manufacturing switches. For example, one optical switch embodiment includes at least one micro electro mechanical system type pivot mirror structure disposed along a path of an optical signal, the structure having a mirror and an actuator, and the mirror having a pivot axis along a first edge and having a second edge rotatable with respect to the pivot axis, the mirror being capable of and arranged to be actuated to pivot betweeen a position parallel to a plane of an optical signal and a position substantially normal to the plane of the optical signal.

  2. SWITCH MECHANISM DIAGNOSIS USING A PATTERN RECOGNITION APPROACH

    E-Print Network [OSTI]

    Chamroukhi, Faicel

    for the diagnosis of switch mechanisms driven by an electric motor is presented in this paper. Its main advantage (see figure 1) are driven by an electric motor and equiped with a clamp locking system so called VCC ("Verrou Carter Coussinet" in french). Figure 1: Switch mechanism driven by an electrical motor

  3. Mechanical switching of ferro-electric rubber

    E-Print Network [OSTI]

    J. M. Adams; M. Warner

    2008-12-09T23:59:59.000Z

    At the A to C transition, smectic elastomers have recently been observed to undergo $\\sim$35% spontaneous shear strains. We first explicitly describe how strains of up to twice this value could be mechanically or electrically induced in Sm-$C$ elastomers by rotation of the director on a cone around the layer normal at various elastic costs depending on constraints. Secondly, for typical sample geometries, we give the various microstructures in Sm-$C$ akin to those seen in nematic elastomers under distortions with constraints. It is possible to give explicit results for the nature of the textures. Chiral Sm-$C$ elastomers are ferro-electric. We calculate how the polarization could be mechanically reversed by large, hard or soft strains of the rubber, depending upon sample geometry.

  4. Plasmon switching: Observation of dynamic surface plasmon steering by

    E-Print Network [OSTI]

    Visser, Taco D.

    Plasmon switching: Observation of dynamic surface plasmon steering by selective mode excitation a plasmon steering method that enables us to dynamically control the direction of surface plasmons generated surface plasmons are launched can be controlled. Experiments confirm that it is possible to distribute

  5. In-situ observation of self-regulated switching behavior in WO{sub 3-x} based resistive switching devices

    SciTech Connect (OSTI)

    Hong, D. S.; Wang, W. X.; Chen, Y. S., E-mail: yschen@aphy.iphy.ac.cn; Sun, J. R.; Shen, B. G. [Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academic of Sciences, Beijing 100190 (China)

    2014-09-15T23:59:59.000Z

    The transmittance of tungsten oxides can be adjusted by oxygen vacancy (V{sub o}) concentration due to its electrochromic property. Here, we report an in-situ observation of resistive switching phenomenon in the oxygen-deficient WO{sub 3-x} planar devices. Besides directly identifying the formation/rupture of dark-colored conductive filaments in oxide layer, the stripe-like WO{sub 3-x} device demonstrated self-regulated switching behavior during the endurance testing, resulting in highly consistent switching parameters after a stabilizing process. For very high V{sub o}s mobility was demonstrated in the WO{sub 3-x} film by the pulse experiment, we suggested that the electric-field-induced homogeneous migration of V{sub o}s was the physical origin for such unique switching characteristics.

  6. Ionwater hydrogen-bond switching observed with 2D IR vibrational echo chemical

    E-Print Network [OSTI]

    Fayer, Michael D.

    Ion­water hydrogen-bond switching observed with 2D IR vibrational echo chemical exchange for review November 8, 2008) The exchange of water hydroxyl hydrogen bonds between anions and water oxygens of anion­ water hydroxyl hydrogen bond switching under thermal equilib- rium conditions as Taw 7 1 ps. Pump

  7. Photo-induced micro-mechanical optical switch

    DOE Patents [OSTI]

    Rajic, Slobodan (Knoxville, TN); Datskos, Panagiotis George (Knoxville, TN); Egert, Charles M. (late of Oak Ridge, TN)

    2002-01-01T23:59:59.000Z

    An optical switch is formed by introducing light lengthwise to a microcantilever waveguide directed toward a second waveguide. The microcantilever is caused to bend by light emitted from a laser diode orthogonal to the microcantilever and at an energy above the band gap, which induces stress as a result of the generation of free carriers. The bending of the waveguide directs the carrier frequency light to a second receptor waveguide or to a non-responsive surface. The switch may be combined in an array to perform multiple switching functions rapidly and at low energy losses.

  8. Electro-mechanical heat switch for cryogenic applications

    DOE Patents [OSTI]

    van den Berg, Marcel L. (Oakland, CA); Batteux, Jan D. (Hayward, CA); Labov, Simon E. (Berkeley, CA)

    2003-01-01T23:59:59.000Z

    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.

  9. Modeling, simulation, and testing of the mechanical dynamics of and RF MEMS switch.

    SciTech Connect (OSTI)

    Sumali, Hartono; Epp, David S.; Massad, Jordan Elias; Dyck, Christopher William; Starr, Michael James

    2005-07-01T23:59:59.000Z

    Mechanical dynamics can be a determining factor for the switching speed of radio-frequency microelectromechanical systems (RF MEMS) switches. This paper presents the simulation of the mechanical motion of a microswitch under actuation. The switch has a plate suspended by springs. When an electrostatic actuation is applied, the plate moves toward the substrate and closes the switch. Simulations are calculated via a high-fidelity finite element model that couples solid dynamics with electrostatic actuation. It incorporates non-linear coupled dynamics and accommodates fabrication variations. Experimental modal analysis gives results in the frequency domain that verifies the natural frequencies and mode shapes predicted by the model. An effective 1D model is created and used to calculate an actuation voltage waveform that minimizes switch velocity at closure. In the experiment, the switch is actuated with this actuation voltage, and the displacements of the switch at various points are measured using a laser Doppler velocimeter through a microscope. The experiments are repeated on several switches from different batches. The experimental results verify the model.

  10. PERSPECTIVES Nano-to-Microscale Mechanical Switches and Fuses Mediate Adhesive Contacts between

    E-Print Network [OSTI]

    Heinrich, Volkmar

    PERSPECTIVES Nano-to-Microscale Mechanical Switches and Fuses Mediate Adhesive Contacts between to their molecular origins. The present work focuses on nano-to-microscale regulatory aspects that mediate and that they had to be primarily mechanical. Accordingly, our experimental approach was to study in vitro the nano

  11. Probing the switching mechanism in ZnO nanoparticle memristors

    E-Print Network [OSTI]

    Li, C.; Beirne, G. J.; Kamita, G.; Lakhwani, G.; Wang, J.; Greenham, N. C.

    2014-01-01T23:59:59.000Z

    a cryostat (Oxford Instruments, Optistat CF). After reflection from the back contact of the sample (45o incident angle), the probe beam was incident on a silicon photodiode connected via a current-to-voltage converter to a dual-channel lock... . In this case, although the height of barrier decreases, the charge injection through the barrier shifts 7 from a tunneling mechanism to thermionic emission.24 Furthermore, the hopping mechanism dominates the charge transport inside the film, due...

  12. Hydrogen Bond Switching among Flavin and Amino Acid Side Chains in the BLUF Photoreceptor Observed by Ultrafast Infrared Spectroscopy

    E-Print Network [OSTI]

    van Stokkum, Ivo

    Hydrogen Bond Switching among Flavin and Amino Acid Side Chains in the BLUF Photoreceptor Observed hydrogen-bond network with nearby amino acid side chains, including a highly conserved tyrosine and glutamine. The participation of particular amino acid side chains in the ultrafast hydrogen-bond switching

  13. Switch Switch

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructureProposed Action Title:SustainableDepartment ofSwitch Switch

  14. Spatially Resolved Polarization Switching near a Planar Defect by Design: Mesoscopic Mechanisms at Tilt Grain Boundary in Bismuth Ferrite

    SciTech Connect (OSTI)

    Rodriguez, Brian J [ORNL; Choudhury, S [Pennsylvania State University; Chu, Y. H. [University of California, Berkeley; Bhattacharyya, Abishek [Lehigh University, Bethlehem, PA; Jesse, Stephen [ORNL; Seal, Katyayani [ORNL; Baddorf, Arthur P [ORNL; Ramesh, R. [University of California, Berkeley; Chen, Long-Qing [Pennsylvania State University; Kalinin, Sergei V [ORNL

    2009-01-01T23:59:59.000Z

    The effect of microstructure on ferroelectric domain nucleation in epitaxial bismuth ferrite was probed at a single atomically-defined defect: an artificially fabricated model bicrystal grain boundary (GB). Switching Spectroscopy Piezoresponse Force Microscopy is used to map the variation of local hysteresis loops at the grain boundary and its immediate vicinity. We found the influence of the GB on nucleation to be relatively weak, resulting in a slight shift of the negative nucleation bias to higher (negative) voltages. The mesoscopic mechanisms of grain boundary effect on local polarization switching are studied in detail using phase field modeling, elucidating the complex mechanisms governed by the interplay between ferroelectric and ferroelastic wall energies, depolarization fields, and interface charge. The combination of phase field modeling and SS-PFM allows quantitative analysis of mesoscopic mechanisms for polarization switching, and hence suggests a route for optimizing materials properties through microstructure optimization.

  15. Unraveling Deterministic Mesoscopic Polarization Switching Mechanisms: Spatially Resolved Studies of a Tilt Grain Boundary in Bismuth Ferrite

    SciTech Connect (OSTI)

    Rodriguez, Brian [University College, Dublin; Choudhury, S [Pennsylvania State University; Chu, Y. -H. [National Chiao Tung University, Hsinchu, Taiwan; Bhattacharyya, Abishek [Lehigh University, Bethlehem, PA; Jesse, Stephen [ORNL; Seal, Katyayani [ORNL; Baddorf, Arthur P [ORNL; Ramesh, R. [University of California, Berkeley; Chen, L. Q. [Pennsylvania State University; Kalinin, Sergei [Oak Ridge National Laboratory (ORNL)

    2009-01-01T23:59:59.000Z

    The deterministic mesoscopic mechanism of ferroelectric domain nucleation is probed at a single atomically-defined model defect: an artificially fabricated bicrystal grain boundary (GB) in an epitaxial bismuth ferrite film. Switching spectroscopy piezoresponse force microscopy (SS-PFM) is used to map the variation of local hysteresis loops at the GB and in its immediate vicinity. It is found that the the influence of the GB on nucleation results in a slight shift of the negative nucleation bias to larger voltages. The mesoscopic mechanisms of domain nucleation in the bulk and at the GB are studied in detail using phase-field modeling, elucidating the complex mechanisms governed by the interplay between ferroelectric and ferroelastic wall energies, depolarization fields, and interface charge. The combination of phase-field modeling and SS-PFM allows quantitative analysis of the mesoscopic mechanisms for polarization switching, and hence suggests a route for unraveling the mechanisms of polarization switching at a single defect level and ultimately optimizing materials properties through microstructure engineering.

  16. DFG Proposal Observer design for linear switched differential-algebraic equations

    E-Print Network [OSTI]

    Trenn, Stephan

    of power lines due to harsh weather conditions, or a sudden drop in the energy production by wind turbines then be used to monitor the energy flows through the transmission lines and could prevent overloading. Sudden when whole wind parks are switched off in the presence of too strong winds. Hence a possible

  17. Large Angular Jump Mechanism Observed for Hydrogen Bond Exchange in Aqueous Perchlorate Solution

    SciTech Connect (OSTI)

    Ji, Minbiao; /SLAC, PULSE /Stanford U., Phys. Dept.; Odelius3, Michael; /Stockholm U.; Gaffney1, K.J.; /aff SLAC, PULSE

    2010-06-11T23:59:59.000Z

    The mechanism for hydrogen bond (H-bond) switching in solution has remained subject to debate despite extensive experimental and theoretical studies. We have applied polarization-selective multidimensional vibrational spectroscopy to investigate the H-bond exchange mechanism in aqueous NaClO{sub 4} solution. The results show that a water molecule shifts its donated H-bonds between water and perchlorate acceptors by means of large, prompt angular rotation. Using a jump-exchange kinetic model, we extract an average jump angle of 49 {+-} 4{sup o}, in qualitative agreement with the jump angle observed in molecular dynamics simulations of the same aqueous NaClO{sub 4} solution.

  18. Latching micro optical switch

    DOE Patents [OSTI]

    Garcia, Ernest J; Polosky, Marc A

    2013-05-21T23:59:59.000Z

    An optical switch reliably maintains its on or off state even when subjected to environments where the switch is bumped or otherwise moved. In addition, the optical switch maintains its on or off state indefinitely without requiring external power. External power is used only to transition the switch from one state to the other. The optical switch is configured with a fixed optical fiber and a movable optical fiber. The movable optical fiber is guided by various actuators in conjunction with a latching mechanism that configure the switch in one position that corresponds to the on state and in another position that corresponds to the off state.

  19. Spin transfer switching in current-perpendicular-to-plane spin valve observed by magneto-optical Kerr effect using visible light

    E-Print Network [OSTI]

    Otani, Yoshichika

    Spin transfer switching in current-perpendicular-to-plane spin valve observed by magneto-perpendicular-to-plane spin-valve device. The device consists of three spin-valve elements, each of which comprises-perpendicular-to- plane CPP spin-valve device has been directly observed by using a time resolved x-ray microscopy7 while

  20. Quantum mechanical observer and superstring/M theory

    E-Print Network [OSTI]

    M. Dance

    2008-12-31T23:59:59.000Z

    Terms are suggested for inclusion in a Lagrangian density as seen by an observer O2, to represent the dynamics of a quantum mechanical observer O1 that is an initial stage in an observation process. This paper extends an earlier paper which suggested that the centre-of-mass kinetic energy of O1 could correspond to, and possibly underlie, the Lagrangian density for bosonic string theory, where the worldsheet coordinates are the coordinates which O1 can observe. The present paper considers a fermion internal to O1, in addition to O1's centre of mass. It is suggested that quantum mechanical uncertainties in the transformation between O1's and O2's reference systems might require O2 to use $d$ spinor fields for this fermion, where $d$ is the number of spacetime dimensions. If this is the case, and if the symmetry/observability arguments in arXiv:hep-th/0601104 apply, the resulting Lagrangian density for the dynamics of O1 might resemble, or even underlie, superstring/M theory.

  1. Adaptive observer-based switched control for electropneumatic clutch actuator with

    E-Print Network [OSTI]

    Johansen, Tor Arne

    -based pressure observer which is combined with a sliding mode controller for control of a pneumatic servo pressures, friction state and parameters, and clutch load characteristic parameters. The paper focus from a heavy duty test truck, showing no significant loss of performance due to lack of a pressure

  2. Observation of non-Markovian micro-mechanical Brownian motion

    E-Print Network [OSTI]

    S. Groeblacher; A. Trubarov; N. Prigge; M. Aspelmeyer; J. Eisert

    2015-02-22T23:59:59.000Z

    At the heart of understanding the emergence of a classical world from quantum theory is the insight that all macroscopic quantum systems are to some extent coupled to an environment and hence are open systems. The associated loss of quantum coherence, i.e. decoherence, is also detrimental for quantum information processing applications. In contrast, properly engineered quantum noise can counteract decoherence and can even be used in robust quantum state generation. To exploit the detailed dynamics of a quantum system it is therefore crucial to obtain both good knowledge and control over its environment. An explicit modelling of the environment, however, may often not be possible. In this case, simplifying assumptions concerning the nature of the underlying quantum noise are being made that do not necessarily hold for real devices. Micro- and nano-mechanical resonators constitute prominent examples. They are now emerging as promising devices for quantum science. Because of their complex solid-state nature, the properties of their intrinsic decoherence mechanisms have been the subject of intense research for decades. Here we present a method to reconstruct the relevant properties of the environment, that is, its spectral density, of the centre of mass motion of a micro-mechanical oscillator. We observe a clear signature of non-Markovian Brownian motion, which is in contrast to the current paradigm to treat the thermal environment of mechanical quantum resonators as fully Markovian. The presented method, inspired by methods of system identification, can easily be transferred to other harmonic systems that are embedded in a complex environment, for example electronic or nuclear spin states in a solid state matrix. Our results also open up a route for mechanical quantum state engineering via coupling to unorthodox reservoirs.

  3. The switching dynamics of the bacterial flagellar motor

    E-Print Network [OSTI]

    Siebe B. van Albada; Sorin Tanase-Nicola; Pieter Rein ten Wolde

    2008-11-14T23:59:59.000Z

    Many swimming bacteria are propelled by flagellar motors that stochastically switch between the clockwise and counterclockwise rotation direction. While the switching dynamics are one of the most important characteristics of flagellar motors, the mechanisms that control switching are poorly understood. We present a statistical-mechanical model of the flagellar rotary motor, which consists of a number of stator proteins that drive the rotation of a ring of rotor proteins, which in turn drives the rotation of a flagellar filament. At the heart of our model is the assumption that the rotor protein complex can exist in two conformational states corresponding to the two respective rotation directions, and that switching between these states depends on interactions with the stator proteins. This naturally couples the switching dynamics to the rotation dynamics, making the switch sensitive to torque and speed. Another key element of our model is that after a switching event, it takes time for the load to build up, due to polymorphic transitions of the filament. Our model predicts that this slow relaxation dynamics of the filament, in combination with the load dependence of the switching frequency, leads to a characteristic switching time, in agreement with recent observations.

  4. High-G testing of MEMS mechanical non-volatile memory and silicon re-entry switch.

    SciTech Connect (OSTI)

    Baker, Michael Sean; Pohl, Kenneth Roy

    2005-10-01T23:59:59.000Z

    Two different Sandia MEMS devices have been tested in a high-g environment to determine their performance and survivability. The first test was performed using a drop-table to produce a peak acceleration load of 1792 g's over a period of 1.5 ms. For the second test the MEMS devices were assembled in a gun-fired penetrator and shot into a cement target at the Army Waterways Experiment Station in Vicksburg Mississippi. This test resulted in a peak acceleration of 7191 g's for a duration of 5.5 ms. The MEMS devices were instrumented using the MEMS Diagnostic Extraction System (MDES), which is capable of driving the devices and recording the device output data during the high-g event, providing in-flight data to assess the device performance. A total of six devices were monitored during the experiments, four mechanical non-volatile memory devices (MNVM) and two Silicon Reentry Switches (SiRES). All six devices functioned properly before, during, and after each high-g test without a single failure. This is the first known test under flight conditions of an active, powered MEMS device at Sandia.

  5. Cathode heating mechanisms in pseudospark plasma switches Timothy J. Sommerer,`) Hoyoung Pak,b) and Mark J. Kushnef)

    E-Print Network [OSTI]

    Kushner, Mark

    the switch will close (that is, the smallestpossiblepressure-electrode spacingproduct by operatingat low valuesof pressureX electrodespacing (pd product). In spite of operatingat low pressures( .C1

  6. IP SwitchingIP Switching and Label Switchingand Label Switching

    E-Print Network [OSTI]

    Jain, Raj

    Raj Jain 1 IP SwitchingIP Switching and Label Switchingand Label Switching Raj Jain Professor Switching vs routing q IP Switching (Ipsilon) q Tag Switching (CISCO) q Multi-protocol label switching a tag. Exit router strips it off. H R R R H H HUntagged Packet Tagged packet #12;Raj Jain 9 Tag

  7. Percolation mechanism through trapping/de-trapping process at defect states for resistive switching devices with structure of Ag/Si{sub x}C{sub 1?x}/p-Si

    SciTech Connect (OSTI)

    Liu, Yanhong; Gao, Ping; Li, La; Peng, Wei [School of Physics and Optoelectronic Engineering, Dalian University of Technology, No. 2 Linggong Road, Ganjingzi District, Dalian 116024 (China); Jiang, Xuening; Zhang, Jialiang [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, No. 2 Linggong Road, Ganjingzi District, Dalian 116024 (China)

    2014-08-14T23:59:59.000Z

    Pure Si{sub x}C{sub 1?x} (x?>?0.5) and B-containing Si{sub x}C{sub 1?x} (x?>?0.5) based resistive switching devices (RSD) with the structure of Ag/Si{sub x}C{sub 1?x}/p-Si were fabricated and their switching characteristics and mechanism were investigated systematically. Percolation mechanism through trapping/ de-trapping at defect states was suggested for the switching process. Through the introduction of B atoms into Si{sub x}C{sub 1?x}, the density of defect states was reduced, then, the SET and RESET voltages were also decreased. Based on the percolation theory, the dependence of SET/RESET voltage on the density of defect states was analyzed. These results supply a deep understanding for the SiC-based RSD, which have a potential application in extreme ambient conditions.

  8. Optical switch

    DOE Patents [OSTI]

    Reedy, R.P.

    1987-11-10T23:59:59.000Z

    An optical switching device is provided whereby light from a first glass fiber or a second glass fiber may be selectively transmitted into a third glass fiber. Each glass fiber is provided with a focusing and collimating lens system. In one mode of operation, light from the first glass fiber is reflected by a planar mirror into the third glass fiber. In another mode of operation, light from the second glass fiber passes directly into the third glass fiber. The planar mirror is attached to a rotatable table which is rotated to provide the optical switching. 3 figs.

  9. Switching it up | EMSL

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Switching it up Switching it up Released: March 23, 2015 Mapping redox switches in cyanobacteria advances use as biofuel Scientist mapped more than 2,100 sites that may switch...

  10. The Dynamics of Bistable Switching Behavior in Limit Cycle Systems with Additive Noise

    E-Print Network [OSTI]

    Michael A. Schwemmer; Jay M. Newby

    2015-01-23T23:59:59.000Z

    Additive noise is known to produce counter-intuitive behaviors in nonlinear dynamical systems. Previously, it was shown that systems with a deterministic limit cycle can display bistable switching between metastable states in the presence of asymmetric additive white noise. Here, we systematically analyze the dynamics of this bistable behavior and show how the vector field away from the limit cycle influences the rate and directionality of the bistable switching. Using stochastic phase reduction methods, we identify mechanisms underlying different rates of switching and predict when the system will rotate in the opposite direction of the deterministic limit cycle. Thus, this work presents an alternative mechanism for generating a range of bistable switch-like behaviors that have been observed in a number of physical systems.

  11. Advanced Soft Switching Inverter for Reducing Switching and Power...

    Energy Savers [EERE]

    Soft Switching Inverter for Reducing Switching and Power Losses Advanced Soft Switching Inverter for Reducing Switching and Power Losses Presentation from the U.S. DOE Office of...

  12. Observation of phononic helical edge states in a mechanical 'topological insulator'

    E-Print Network [OSTI]

    Ssstrunk, Roman

    2015-01-01T23:59:59.000Z

    A topological insulator is characterized by a dichotomy between the interior and the edge of a finite system: While the bulk has a non-zero energy gap, the edges are forced to sustain excitations traversing these gaps. Originally proposed for electrons governed by quantum mechanics, it has remained an important open question if the same physics can be observed for systems obeying Newton's equations of motion. Here, we report on measurements that characterize the collective behavior of mechanical oscillators exhibiting the phenomenology of the quantum spin hall effect. The phononic edge modes are shown to be helical and we demonstrate their topological protection via the stability against imperfections. Our results open the door to the design of topological acoustic meta-materials that can capitalize on the stability of the surfaces phonons as reliable wave guides.

  13. Observation of plasma instabilities related to dust particle growth mechanisms in electron cyclotron resonance plasmas

    SciTech Connect (OSTI)

    Drenik, A. [Joef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia) [Joef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); CNRS, LAPLACE, 31062 Toulouse/Universit de Toulouse, UPS, INPT, LAPLACE, 118 rte de Narbonne, 31062 Toulouse Cedex 9 (France); Yuryev, P.; Clergereaux, R. [CNRS, LAPLACE, 31062 Toulouse/Universit de Toulouse, UPS, INPT, LAPLACE, 118 rte de Narbonne, 31062 Toulouse Cedex 9 (France)] [CNRS, LAPLACE, 31062 Toulouse/Universit de Toulouse, UPS, INPT, LAPLACE, 118 rte de Narbonne, 31062 Toulouse Cedex 9 (France); Vesel, A. [Joef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia)] [Joef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Margot, J. [Groupe de Physique des Plasmas, Dpartement de Physique, Universit de Montral, CP 6128, Succursale Centre-ville, Montral, Qubec H3C 3J7 (Canada)] [Groupe de Physique des Plasmas, Dpartement de Physique, Universit de Montral, CP 6128, Succursale Centre-ville, Montral, Qubec H3C 3J7 (Canada)

    2013-10-15T23:59:59.000Z

    Instabilities are observed in the self-bias voltage measured on a probe immersed in microwave plasma excited at Electron Cyclotron Resonance (ECR). Observed in the MHz range, they were systematically measured in dust-free or dusty plasmas (obtained for different conditions of applied microwave powers and acetylene flow rates). Two characteristic frequencies, well described as lower hybrid oscillations, can be defined. The first one, in the 6070 MHz range, appears as a sharp peak in the frequency spectra and is observed in every case. Attributed to ions, its position shift observed with the output power highlights that nucleation process takes place in the dusty plasma. Attributed to lower hybrid oscillation of powders, the second broad peak in the 1020 MHz range leads to the characterization of dust particles growth mechanisms: in the same way as in capacitively coupled plasmas, accumulation of nucleus confined near the probe in the magnetic field followed by aggregation takes place. Then, the measure of electrical instabilities on the self-bias voltage allows characterizing the discharge as well as the chemical processes that take place in the magnetic field region and their kinetics.

  14. Radiation hard vacuum switch

    DOE Patents [OSTI]

    Boettcher, Gordon E. (Albuquerque, NM)

    1990-01-01T23:59:59.000Z

    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.

  15. Synthesis of Uniformly Ultimate Boundedness Switching Laws for Discrete-Time Uncertain Switched Linear Systems

    E-Print Network [OSTI]

    Sontag, Eduardo

    - cations in control of mechanical systems, process control, au- tomotive industry, power systems, aircraft variations and exterior disturbances are considered. The problem of synthesis of switching control laws that orchestrates switching between these subsystems. Properties of this type of model have been studied

  16. Remote switch actuator

    DOE Patents [OSTI]

    Haas, Edwin Gerard; Beauman, Ronald; Palo, Jr., Stefan

    2013-01-29T23:59:59.000Z

    The invention provides a device and method for actuating electrical switches remotely. The device is removably attached to the switch and is actuated through the transfer of a user's force. The user is able to remain physically removed from the switch site obviating need for protective equipment. The device and method allow rapid, safe actuation of high-voltage or high-current carrying electrical switches or circuit breakers.

  17. Apollo Ring Optical Switch

    SciTech Connect (OSTI)

    Maestas, J.H.

    1987-03-01T23:59:59.000Z

    An optical switch was designed, built, and installed at Sandia National Laboratories in Albuquerque, New Mexico, to facilitate the integration of two Apollo computer networks into a single network. This report presents an overview of the optical switch as well as its layout, switch testing procedure and test data, and installation.

  18. Observations

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's Possible for RenewableSpeeding accessSpeeding access(SC)Gas and OilPhaseObservation of aof

  19. Single-crystalline monolayer and multilayer graphene nano switches

    SciTech Connect (OSTI)

    Li, Peng; Cui, Tianhong, E-mail: tcui@me.umn.edu [State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua University, Beijing 100084 (China); Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Jing, Gaoshan [State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instruments, Tsinghua University, Beijing 100084 (China); Zhang, Bo; Sando, Shota [Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2014-03-17T23:59:59.000Z

    Growth of monolayer, bi-layer, and tri-layer single-crystalline graphene (SCG) using chemical vapor deposition method is reported. SCG's mechanical properties and single-crystalline nature were characterized and verified by atomic force microscope and Raman spectroscopy. Electro-mechanical switches based on mono- and bi-layer SCG were fabricated, and the superb properties of SCG enable the switches to operate at pull-in voltage as low as 1?V, and high switching speed about 100?ns. These devices exhibit lifetime without a breakdown of over 5000 cycles, far more durable than any other graphene nanoelectromechanical system switches reported.

  20. Unipolar resistive switching behavior of amorphous YCrO{sub 3} films for nonvolatile memory applications

    SciTech Connect (OSTI)

    Sharma, Yogesh, E-mail: yks181086@gmail.com, E-mail: rkatiyar@uprrp.edu; Misra, Pankaj; Katiyar, Ram S., E-mail: yks181086@gmail.com, E-mail: rkatiyar@uprrp.edu [Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, Puerto Rico 00936-8377 (United States)

    2014-08-28T23:59:59.000Z

    Amorphous YCrO{sub 3} (YCO) films were prepared on Pt/TiO{sub 2}/SiO{sub 2}/Si substrate by pulsed laser deposition in order to investigate resistive switching (RS) phenomenon. The Pt/YCO/Pt device showed stable unipolar RS with resistance ratio of ?10{sup 5} between low and high resistance states, excellent endurance and retention characteristics, as well as, non-overlapping switching voltages with narrow dispersions. Based on the x-ray photoelectron spectroscopy and temperature dependent switching characteristics, observed RS was mainly ascribed to the oxygen vacancies. Moreover, current-voltage characteristics of the device in low and high resistance states were described by Ohmic and trap controlled spacecharge limited conduction mechanisms, respectively.

  1. MEMS relays for make-break power switching applications : {111} silicon etched planar electrical contacts

    E-Print Network [OSTI]

    Weber, Alexis Christian, 1974-

    2008-01-01T23:59:59.000Z

    Relays and switches are of interest in applications such as test equipment, radar, communications, and power systems, amongst others. Unlike solid state switches, mechanical relays provide galvanic isolation across the ...

  2. Alarm toe switch

    DOE Patents [OSTI]

    Ganyard, Floyd P. (Albuquerque, NM)

    1982-01-01T23:59:59.000Z

    An alarm toe switch inserted within a shoe for energizing an alarm circuit n a covert manner includes an insole mounting pad into which a miniature reed switch is fixedly molded. An elongated slot perpendicular to the reed switch is formed in the bottom surface of the mounting pad. A permanent cylindrical magnet positioned in the forward portion of the slot with a diameter greater than the pad thickness causes a bump above the pad. A foam rubber block is also positioned in the slot rearwardly of the magnet and holds the magnet in normal inoperative relation. A non-magnetic support plate covers the slot and holds the magnet and foam rubber in the slot. The plate minimizes bending and frictional forces to improve movement of the magnet for reliable switch activation. The bump occupies the knuckle space beneath the big toe. When the big toe is scrunched rearwardly the magnet is moved within the slot relative to the reed switch, thus magnetically activating the switch. When toe pressure is released the foam rubber block forces the magnet back into normal inoperative position to deactivate the reed switch. The reed switch is hermetically sealed with the magnet acting through the wall so the switch assembly S is capable of reliable operation even in wet and corrosive environments.

  3. Reusable fast opening switch

    DOE Patents [OSTI]

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

    1983-12-21T23:59:59.000Z

    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.

  4. Reusable fast opening switch

    DOE Patents [OSTI]

    Van Devender, John P. (Albuquerque, NM); Emin, David (Albuquerque, NM)

    1986-01-01T23:59:59.000Z

    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.

  5. Reflective HTS switch

    DOE Patents [OSTI]

    Martens, Jon S. (Albuquerque, NM); Hietala, Vincent M. (Placitas, NM); Hohenwarter, Gert K. G. (Madison, WI)

    1994-01-01T23:59:59.000Z

    A HTS switch includes a HTS conductor for providing a superconducting path for an electrical signal and an serpentine wire actuator for controllably heating a portion of the conductor sufficiently to cause that portion to have normal, and not superconducting, resistivity. Mass of the portion is reduced to decrease switching time.

  6. Reflective HTS switch

    DOE Patents [OSTI]

    Martens, J.S.; Hietala, V.M.; Hohenwarter, G.K.G.

    1994-09-27T23:59:59.000Z

    A HTS (High Temperature Superconductor) switch includes a HTS conductor for providing a superconducting path for an electrical signal and an serpentine wire actuator for controllably heating a portion of the conductor sufficiently to cause that portion to have normal, and not superconducting, resistivity. Mass of the portion is reduced to decrease switching time. 6 figs.

  7. Erected mirror optical switch

    DOE Patents [OSTI]

    Allen, James J.

    2005-06-07T23:59:59.000Z

    A microelectromechanical (MEM) optical switching apparatus is disclosed that is based on an erectable mirror which is formed on a rotatable stage using surface micromachining. An electrostatic actuator is also formed on the substrate to rotate the stage and mirror with a high angular precision. The mirror can be erected manually after fabrication of the device and used to redirect an incident light beam at an arbitrary angel and to maintain this state in the absence of any applied electrical power. A 1.times.N optical switch can be formed using a single rotatable mirror. In some embodiments of the present invention, a plurality of rotatable mirrors can be configured so that the stages and mirrors rotate in unison when driven by a single micromotor thereby forming a 2.times.2 optical switch which can be used to switch a pair of incident light beams, or as a building block to form a higher-order optical switch.

  8. Fast superconducting magnetic field switch

    DOE Patents [OSTI]

    Goren, Yehuda (Mountain View, CA); Mahale, Narayan K. (The Woodlands, TX)

    1996-01-01T23:59:59.000Z

    The superconducting magnetic switch or fast kicker magnet is employed with electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater that the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles.

  9. Solid state switch

    DOE Patents [OSTI]

    Merritt, B.T.; Dreifuerst, G.R.

    1994-07-19T23:59:59.000Z

    A solid state switch, with reverse conducting thyristors, is designed to operate at 20 kV hold-off voltage, 1,500 A peak, 1.0 [mu]s pulsewidth, and 4,500 pps, to replace thyratrons. The solid state switch is more reliable, more economical, and more easily repaired. The switch includes a stack of circuit card assemblies, a magnetic assist and a trigger chassis. Each circuit card assembly contains a reverse conducting thyristor, a resistor capacitor network, and triggering circuitry. 6 figs.

  10. Observations of Ferroelastic Switching by Raman Spectroscopy

    E-Print Network [OSTI]

    Bolon, Amy Marie

    2012-02-14T23:59:59.000Z

    Thermal barrier coatings (TBCs) have become an important part of turbine technology by providing thermal protection to the underlying metallic components. These coatings are typically made from a zirconia-based ceramics which have a low thermal...

  11. Observations of Ferroelastic Switching by Raman Spectroscopy

    E-Print Network [OSTI]

    Bolon, Amy Marie

    2012-02-14T23:59:59.000Z

    26. .................................. 6 Figure 4. The figure shows the phase diagram for the GdO1.5-ZrO2-AlO1.5 system. The composition Gd2Zr2O7 is not thermodynamically stable with the TGO, a phase change to a perovskite structure occurs when.... This composition has a pyrochlore structure, when alumina is introduced to that structure it becomes the perovskite gadolinium aluminate (GAP) phase with a different thermal expansion coefficient27. Additionally, gadolinium zirconate has very poor toughness due...

  12. In Situ Observations of the Atomistic Mechanisms of Ni Catalyzed Low Temperature Graphene Growth

    E-Print Network [OSTI]

    Patera, Laerte L.; Africh, Cristina; Weatherup, Robert S.; Blume, Raoul; Bhardwaj, Sunil; Castellarin- Cudia, Carla; Knop-Gericke, Axel; Schloegl, Robert; Comelli, Giovanni; Hofmann, Stephan; Cepek, Cinzia

    2013-08-08T23:59:59.000Z

    performed at the ISISS beamline of the Fritz Haber Institute located at the BESSY II synchrotron facility in Berlin. The high-pressure setup consists mainly of a reaction cell (base pressure ?10-7mbar) attached to a set of differentially pumped... during graphene growth, measured using synchrotron radiation (see Methods). We observe the appearance of the same four, principal components as identified earlier (CA, CDis, CGr and CB). On C2H4 exposure, CA and a weak CDis signal initially appear...

  13. Plasmonic enhanced ultrafast switch.

    SciTech Connect (OSTI)

    Subramania,Ganapathi Subramanian; Reno, John Louis; Passmore, Brandon Scott; Harris, Tom.; Shaner, Eric Arthur; Barrick, Todd A.

    2009-09-01T23:59:59.000Z

    Ultrafast electronic switches fabricated from defective material have been used for several decades in order to produce picosecond electrical transients and TeraHertz radiation. Due to the ultrashort recombination time in the photoconductor materials used, these switches are inefficient and are ultimately limited by the amount of optical power that can be applied to the switch before self-destruction. The goal of this work is to create ultrafast (sub-picosecond response) photoconductive switches on GaAs that are enhanced through plasmonic coupling structures. Here, the plasmonic coupler primarily plays the role of being a radiation condenser which will cause carriers to be generated adjacent to metallic electrodes where they can more efficiently be collected.

  14. An optical switch

    DOE Patents [OSTI]

    Christophorou, L.G.; Hunter, S.R.

    1987-04-30T23:59:59.000Z

    The invention is a gas mixture for a diffuse discharge switch having an electron attaching gas wherein electron attachment is brought about by indirect excitation of molecules to long live states by exposure to laser light. 3 figs.

  15. Cygnus Water Switch Jitter

    SciTech Connect (OSTI)

    Charles V. Mitton, George D. Corrow, Mark D. Hansen, David J. Henderson, et al.

    2008-03-01T23:59:59.000Z

    The Cygnus Dual Beam Radiographic Facility consists of two identical radiographic sources - Cygnus 1 and Cygnus 2. Each source has the following x-ray output: 1-mm diameter spot size, 4 rad at 1 m, 50-ns Full Width Half Max. The diode pulse has the following electrical specifications: 2.25 MV, 60 kA, 60 ns. This Radiographic Facility is located in an underground tunnel test area at the Nevada Test Site (NTS). The sources were developed to produce high-resolution images on subcritical tests which are performed at NTS. Subcritical tests are single-shot, high-value events. For this application, it is desirable to maintain a high level of reproducibility in source output. The major components of the Cygnus machines are: Marx generator, water-filled pulseforming line (PFL), water-filled coaxial transmission line, three-cell inductive voltage adder, and rod-pinch diode. A primary source of fluctuation in Cygnus shot-to-shot performance is jitter in breakdown of the main PFL switch, which is a self-break switch. The PFL switch breakdown time determines the peak PFL charging voltage, which ultimately affects the diode pulse. Therefore, PFL switch jitter contributes to shot-to-shot variation in source endpoint energy and dose. In this paper we will present PFL switch jitter analysis for both Cygnus machines and give the correlation with diode performance. For this analysis the PFL switch on each machine was maintained at a single gap setting which has been used for the majority of shots at NTS. In addition to this analysis, PFL switch performance for different switch gap settings taken recently will be examined. Lastly, implications of source jitter for radiographic diagnosis of subcritical shots will be discussed.

  16. Cygnus PFL Switch Jitter

    SciTech Connect (OSTI)

    C. Mitton, G. Corrow, M. Hansen, D. Henderson, et al.

    2007-07-21T23:59:59.000Z

    The Cygnus Dual Beam Radiographic Facility consists of two identical radiographic sources: Cygnus 1 and Cygnus 2. Each source has the following X-ray output: 1-mm diameter spot size, 4 rads at 1 m, 50-ns full-widthhalf-maximum. The diode pulse has the following electrical specifications: 2.25 MV, 60 kA, 60 ns. This Radiographic Facility is located in an underground tunnel test area at the Nevada Test Site (NTS). The sources were developed to produce high-resolution images on subcritical tests performed at NTS. Subcritical tests are single-shot, high-value events. For this application, it is desirable to maintain a high level of reproducibility in source output. The major components of the Cygnus machines are Marx generator, water-filled pulse forming line (PFL), water-filled coaxial transmission line, threecell inductive voltage adder, and rod-pinch diode. A primary source of fluctuation in Cygnus shot-to-shot performance may be jitter in breakdown of the main PFL switch, which is a self-break switch. The PFL switch breakdown time determines the peak PFL charging voltage, which ultimately affects the source X-ray spectrum and dose. Therefore, PFL switch jitter may contribute to shot-to-shot variation in these parameters, which are crucial to radiographic quality. In this paper we will present PFL switch jitter analysis for both Cygnus machines and present the correlation with dose. For this analysis, the PFL switch on each machine was maintained at a single gap setting, which has been used for the majority of shots at NTS. In addition the PFL switch performance for one larger switch gap setting will be examined.

  17. Low inductance gas switching.

    SciTech Connect (OSTI)

    Chavez, Ray; Harjes, Henry Charles III; Wallace, Zachariah; Elizondo, Juan E.

    2007-10-01T23:59:59.000Z

    The laser trigger switch (LTS) is a key component in ZR-type pulsed power systems. In ZR, the pulse rise time through the LTS is > 200 ns and additional stages of pulse compression are required to achieve the desired <100 ns rise time. The inductance of the LTS ({approx}500nH) in large part determines the energy transfer time through the switch and there is much to be gained in improving system performance and reducing system costs by reducing this inductance. The current path through the cascade section of the ZR LTS is at a diameter of {approx} 6-inches which is certainly not optimal from an inductance point of view. The LTS connects components of much greater diameter (typically 4-5 feet). In this LDRD the viability of switch concepts in which the diameter of cascade section is greatly increased have been investigated. The key technical question to be answered was, will the desired multi-channel behavior be maintained in a cascade section of larger diameter. This LDRD proceeded in 2 distinct phases. The original plan for the LDRD was to develop a promising switch concept and then design, build, and test a moderate scale switch which would demonstrate the key features of the concept. In phase I, a switch concept which meet all electrical design criteria and had a calculated inductance of 150 nH was developed. A 1.5 MV test switch was designed and fabrication was initiated. The LDRD was then redirected due to budgetary concerns. The fabrication of the switch was halted and the focus of the LDRD was shifted to small scale experiments designed to answer the key technical question concerning multi-channel behavior. In phase II, the Multi-channel switch test bed (MCST) was designed and constructed. The purpose of MCST was to provide a versatile, fast turn around facility for the study the multi-channel electrical breakdown behavior of a ZR type cascade switch gap in a parameter space near that of a ZR LTS. Parameter scans on source impedance, gap tilt, gap spacing and electrode diameter were conducted.

  18. Switching power pulse system

    DOE Patents [OSTI]

    Aaland, K.

    1983-08-09T23:59:59.000Z

    A switching system for delivering pulses of power from a source to a load using a storage capacitor charged through a rectifier, and maintained charged to a reference voltage level by a transistor switch and voltage comparator. A thyristor is triggered to discharge the storage capacitor through a saturable reactor and fractional turn saturable transformer having a secondary to primary turn ratio N of n:l/n = n[sup 2]. The saturable reactor functions as a soaker'' while the thyristor reaches saturation, and then switches to a low impedance state. The saturable transformer functions as a switching transformer with high impedance while a load coupling capacitor charges, and then switches to a low impedance state to dump the charge of the storage capacitor into the load through the coupling capacitor. The transformer is comprised of a multilayer core having two secondary windings tightly wound and connected in parallel to add their output voltage and reduce output inductance, and a number of single turn windings connected in parallel at nodes for the primary winding, each single turn winding linking a different one of the layers of the multilayer core. The load may be comprised of a resistive beampipe for a linear particle accelerator and capacitance of a pulse forming network. To hold off discharge of the capacitance until it is fully charged, a saturable core is provided around the resistive beampipe to isolate the beampipe from the capacitance until it is fully charged. 5 figs.

  19. Thermionic gas switch

    DOE Patents [OSTI]

    Hatch, G.L.; Brummond, W.A.; Barrus, D.M.

    1984-04-05T23:59:59.000Z

    The present invention is directed to an improved temperature responsive thermionic gas switch utilizing a hollow cathode and a folded emitter surface area. The folded emitter surface area of the thermionic switch substantially increases the on/off ratio by changing the conduction surface area involved in the two modes thereof. The improved switch of this invention provides an on/off ratio of 450:1 compared to the 10:1 ratio of the prior known thermionic switch, while providing for adjusting the on current. In the improved switch of this invention the conduction area is made small in the off mode, while in the on mode the conduction area is made large. This is achieved by utilizing a folded hollow cathode configuration and utilizing a folded emitter surface area, and by making the dimensions of the folds small enough so that a space charge will develop in the convolutions of the folds and suppress unignited current, thus limiting the current carrying surface in the off mode.

  20. Switching power supply

    DOE Patents [OSTI]

    Mihalka, A.M.

    1984-06-05T23:59:59.000Z

    The invention is a repratable capacitor charging, switching power supply. A ferrite transformer steps up a dc input. The transformer primary is in a full bridge configuration utilizing power MOSFETs as the bridge switches. The transformer secondary is fed into a high voltage, full wave rectifier whose output is connected directly to the energy storage capacitor. The transformer is designed to provide adequate leakage inductance to limit capacitor current. The MOSFETs are switched to the variable frequency from 20 to 50 kHz to charge a capacitor from 0.6 kV. The peak current in a transformer primary and secondary is controlled by increasing the pulse width as the capacitor charges. A digital ripple counter counts pulses and after a preselected desired number is reached an up-counter is clocked.

  1. Microfabricated triggered vacuum switch

    DOE Patents [OSTI]

    Roesler, Alexander W. (Tijeras, NM); Schare, Joshua M. (Albuquerque, NM); Bunch, Kyle (Albuquerque, NM)

    2010-05-11T23:59:59.000Z

    A microfabricated vacuum switch is disclosed which includes a substrate upon which an anode, cathode and trigger electrode are located. A cover is sealed over the substrate under vacuum to complete the vacuum switch. In some embodiments of the present invention, a metal cover can be used in place of the trigger electrode on the substrate. Materials used for the vacuum switch are compatible with high vacuum, relatively high temperature processing. These materials include molybdenum, niobium, copper, tungsten, aluminum and alloys thereof for the anode and cathode. Carbon in the form of graphitic carbon, a diamond-like material, or carbon nanotubes can be used in the trigger electrode. Channels can be optionally formed in the substrate to mitigate against surface breakdown.

  2. Transparent electrode for optical switch

    DOE Patents [OSTI]

    Goldhar, J.; Henesian, M.A.

    1984-10-19T23:59:59.000Z

    The invention relates generally to optical switches and techniques for applying a voltage to an electro-optical crystal, and more particularly, to transparent electodes for an optical switch. System architectures for very large inertial confinement fusion (ICF) lasers require active optical elements with apertures on the order of one meter. Large aperture optical switches are needed for isolation of stages, switch-out from regenerative amplifier cavities and protection from target retroreflections.

  3. A steering mechanism for phototaxis in Chlamydomonas

    E-Print Network [OSTI]

    Rachel R. Bennett; Ramin Golestanian

    2014-12-19T23:59:59.000Z

    Chlamydomonas shows both positive and negative phototaxis. It has a single eyespot near its equator and as the cell rotates during forward motion the light signal received by the eyespot varies. We use a simple mechanical model of Chlamydomonas that couples the flagellar beat pattern to the light intensity at the eyespot to demonstrate a mechanism for phototactic steering that is consistent with observations. The direction of phototaxis is controlled by a parameter in our model and the steering mechanism is robust to noise. Our model shows switching between directed phototaxis when the light is on and run-and-tumble behaviour in the dark.

  4. Switching power pulse system

    DOE Patents [OSTI]

    Aaland, Kristian (Livermore, CA)

    1983-01-01T23:59:59.000Z

    A switching system for delivering pulses of power from a source (10) to a load (20) using a storage capacitor (C3) charged through a rectifier (D1, D2), and maintained charged to a reference voltage level by a transistor switch (Q1) and voltage comparator (12). A thyristor (22) is triggered to discharge the storage capacitor through a saturable reactor (18) and fractional turn saturable transformer (16) having a secondary to primary turn ratio N of n:l/n=n.sup.2. The saturable reactor (18) functions as a "soaker" while the thyristor reaches saturation, and then switches to a low impedance state. The saturable transformer functions as a switching transformer with high impedance while a load coupling capacitor (C4) charges, and then switches to a low impedance state to dump the charge of the storage capacitor (C3) into the load through the coupling capacitor (C4). The transformer is comprised of a multilayer core (26) having two secondary windings (28, 30) tightly wound and connected in parallel to add their output voltage and reduce output inductance, and a number of single turn windings connected in parallel at nodes (32, 34) for the primary winding, each single turn winding linking a different one of the layers of the multilayer core. The load may be comprised of a resistive beampipe (40) for a linear particle accelerator and capacitance of a pulse forming network (42). To hold off discharge of the capacitance until it is fully charged, a saturable core (44) is provided around the resistive beampipe (40) to isolate the beampipe from the capacitance (42) until it is fully charged.

  5. Magnetic switch for reactor control rod

    SciTech Connect (OSTI)

    Germer, J.H.

    1986-04-15T23:59:59.000Z

    This patent describes a control rod system for a nuclear reactor utilizing an electromagnetic grapple mechanism for holding and releasing a control rod, the improvement comprising a magnetic reed switch assembly having a Curie-point magnetic shunt and responsive to reactor coolant temperature for short circuiting the electromagnetic grapple mechanism causing release of the control rod when the coolant temperature reaches the Curie-point of the magnetic shunt. The magnetic reed switch assembly includes a: a permanent magnet, a pair of magnetic pole pieces located at and in contact with opposite ends of the permanent magnet, the Curie-point magnetic shunt being positioned adjacent the permanent magnet and in contact with the pair of magnetic pole pieces, and a reed switch positioned intermediate the pole pieces and provided with a pair of ferromagnetic reeds, a nonmagnetic enclosure around the reeds, a first of the reeds being secured at one end to a first of the pair of pole pieces, a second of the reeds having one end extending into and secured to a hollow member positioned in and extending through a second of the pair of pole pieces, the one end of the second of the reeds secured to a condector adapted to be connected to the electromagnetic grapple mechanism.

  6. A UPF3-mediated regulatory switch that maintains RNA surveillance

    E-Print Network [OSTI]

    Wilkinson, Miles F.

    A UPF3-mediated regulatory switch that maintains RNA surveillance Wai-Kin Chan1, Angela D Bhalla1RNAs. The regulation of NMD is poorly understood. Here we identify a regulatory mechanism acting on two related UPF (up-frameshift) factors crucial for NMD: UPF3A and UPF3B. This regulatory mechanism, which reduces the level of UPF3A

  7. Plasma opening switch

    DOE Patents [OSTI]

    Savage, Mark E. (Albuquerque, NM); Mendel, Jr., Clifford W. (Albuquerque, NM)

    2001-01-01T23:59:59.000Z

    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.

  8. The quantum cryptographic switch

    E-Print Network [OSTI]

    Srinatha Narayanaswamy; Omkar Srikrishna; R. Srikanth; Subhashish Banerjee; Anirban Pathak

    2011-11-21T23:59:59.000Z

    We illustrate using a quantum system the principle of a cryptographic switch, in which a third party (Charlie) can control to a continuously varying degree the amount of information the receiver (Bob) receives, after the sender (Alice) has sent her information. Suppose Charlie transmits a Bell state to Alice and Bob. Alice uses dense coding to transmit two bits to Bob. Only if the 2-bit information corresponding to choice of Bell state is made available by Charlie to Bob can the latter recover Alice's information. By varying the information he gives, Charlie can continuously vary the information recovered by Bob. The performance of the protocol subjected to the squeezed generalized amplitude damping channel is considered. We also present a number of practical situations where a cryptographic switch would be of use.

  9. SWITCH Model AND Data Description: 2050 Timeframe................................................ 2 SWITCH Model Description ........................................................................................................2

    E-Print Network [OSTI]

    Kammen, Daniel M.

    , Berkeley. SWITCH Model Description 1. Study Years, Months, Dates and Hours To simulate power system1 SWITCH Model AND Data Description: 2050 Timeframe................................................ 2 SWITCH Model Description

  10. CREE: Making the Switch

    ScienceCinema (OSTI)

    Grider, David; Palmer, John

    2014-04-09T23:59:59.000Z

    CREE, with the help of ARPA-E funding, has developed a Silicon Carbide (SIC) transistor which can be used to create solid state transformers capable of meeting the unique needs of the emerging smart grid. SIC transistors are different from common silicon computer chips in that they handle grid scale voltages with ease and their high frequency switching is well suited to the intermittent nature of renewable energy generation.

  11. CREE: Making the Switch

    SciTech Connect (OSTI)

    Grider, David; Palmer, John

    2014-03-06T23:59:59.000Z

    CREE, with the help of ARPA-E funding, has developed a Silicon Carbide (SIC) transistor which can be used to create solid state transformers capable of meeting the unique needs of the emerging smart grid. SIC transistors are different from common silicon computer chips in that they handle grid scale voltages with ease and their high frequency switching is well suited to the intermittent nature of renewable energy generation.

  12. Ultrafast gas switching experiments

    SciTech Connect (OSTI)

    Frost, C.A.; Martin, T.H.; Patterson, P.E.; Rinehart, L.F.; Rohwein, G.J.; Roose, L.D.; Aurand, J.F.; Buttram, M.T.

    1996-11-01T23:59:59.000Z

    We describe recent experiments which studied the physics of ultrafast gas breakdown under the extreme overvoltages which occur when a high pressure gas switch is pulse charged to hundreds of kV in 1 ns or less. The highly overvolted peaking gaps produce powerful electromagnetic pulses with risetimes < 100 ps which can be used for ultrawideband radar systems, particle accelerators, laser drivers, bioelectromagnetic studies, electromagnetic effects testing, and for basic studies of gas breakdown physics. We have produced and accurately measured pulses with 50 to 100 ps risetimes to peak levels of 75 to 160 kV at pulse repetition frequencies (PRF) to I kHz. A unique gas switch was developed to hold off hundreds of kV with parasitic inductance less than I nH. An advanced diagnostic system using Fourier compensation was developed to measure single-shot risetimes below 35 ps. The complete apparatus is described and wave forms are presented. The measured data are compared with a theoretical model which predicts key features including dependence on gas species and pressure. We have applied this technology to practical systems driving ultrawideband radiating antennas and bounded wave simulators. For example, we have developed a thyristor/pulse transformer based system using a highly overvolted cable switch. This pulser driving a Sandia- designed TEM cell, provides an ultra wideband impulse with < 200 ps risetime to the test object at a PRF > 1 kHz at > 100 kV/m E field.

  13. APEX-CHAMP+ high-J CO observations of low-mass young stellar objects: IV. Mechanical and radiative feedback

    E-Print Network [OSTI]

    Y?ld?z, Umut A; van Dishoeck, Ewine F; Hogerheijde, Michiel R; Karska, Agata; Belloche, Arnaud; Endo, Akira; Frieswijk, Wilfred; Gsten, Rolf; van Kempen, Tim A; Leurini, Silvia; Nagy, Zsofia; Prez-Beaupuits, Juan-Pablo; Risacher, Christophe; van der Marel, Nienke; van Weeren, Reinout J; Wyrowski, Friedrich

    2015-01-01T23:59:59.000Z

    During the embedded stage of star formation, bipolar molecular outflows and UV radiation from the protostar are important feedback processes. Our aim is to quantify the feedback, mechanical and radiative, for a large sample of low-mass sources. The outflow activity is compared to radiative feedback in the form of UV heating by the accreting protostar to search for correlations and evolutionary trends. Large-scale maps of 26 young stellar objects, which are part of the Herschel WISH key program are obtained using the CHAMP+ instrument on the APEX (12CO and 13CO 6-5), and the HARP-B instrument on the JCMT (12CO and 13CO 3-2). Maps are used to determine outflow parameters and envelope models are used to quantify the amount of UV-heated gas and its temperature from 13CO 6-5 observations. All sources in our sample show outflow activity and the outflow force, F_CO, is larger for Class 0 sources than for Class I sources, even if their luminosities are comparable. The outflowing gas typically extends to much greater ...

  14. Compound semiconductor optical waveguide switch

    DOE Patents [OSTI]

    Spahn, Olga B.; Sullivan, Charles T.; Garcia, Ernest J.

    2003-06-10T23:59:59.000Z

    An optical waveguide switch is disclosed which is formed from III-V compound semiconductors and which has a moveable optical waveguide with a cantilevered portion that can be bent laterally by an integral electrostatic actuator to route an optical signal (i.e. light) between the moveable optical waveguide and one of a plurality of fixed optical waveguides. A plurality of optical waveguide switches can be formed on a common substrate and interconnected to form an optical switching network.

  15. Hybrid switch for resonant power converters

    DOE Patents [OSTI]

    Lai, Jih-Sheng; Yu, Wensong

    2014-09-09T23:59:59.000Z

    A hybrid switch comprising two semiconductor switches connected in parallel but having different voltage drop characteristics as a function of current facilitates attainment of zero voltage switching and reduces conduction losses to complement reduction of switching losses achieved through zero voltage switching in power converters such as high-current inverters.

  16. Sensor Switch's Bright Manufacturing Future

    Broader source: Energy.gov [DOE]

    The switch helps with cost effective energy savings by turning off the lights when an occupancy sensor says the room is empty.

  17. Robust adaptive control of switched systems

    E-Print Network [OSTI]

    El-Rifai, Khalid, 1979-

    2007-01-01T23:59:59.000Z

    In this thesis, robust adaptive controllers are developed for classes of switched nonlinear systems. Switched systems are those governed by differential equations, which undergo vector field switching due to sudden changes ...

  18. A probabilistic approach for the classification of railway switch operating states

    E-Print Network [OSTI]

    Chamroukhi, Faicel

    operation diagnosis. #12;Moving Points Electric Motor (380 V) Figure 1. Switch mechanism driven by an electrical motor. The proposed approach, which does not require a physical model of the system, simply uses from signals 2.1 The available data As already mentioned, the available information for each switch

  19. Nanometer Resolution Imaging by SIngle Molecule Switching. |...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nanometer Resolution Imaging by SIngle Molecule Switching. Nanometer Resolution Imaging by SIngle Molecule Switching. Abstract: The fluorescence intensity of single molecules can...

  20. Hairpin DNA Switch for Ultrasensitive Spectrophotometric Detection...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hairpin DNA Switch for Ultrasensitive Spectrophotometric Detection of DNA Hybridization Based on Gold Nanoparticles and Enzyme Hairpin DNA Switch for Ultrasensitive...

  1. Optimized scalable network switch

    DOE Patents [OSTI]

    Blumrich, Matthias A. (Ridgefield, CT); Chen, Dong (Croton On Hudson, NY); Coteus, Paul W. (Yorktown Heights, NY); Gara, Alan G. (Mount Kisco, NY); Giampapa, Mark E. (Irvington, NY); Heidelberger, Philip (Cortlandt Manor, NY); Steinmacher-Burow, Burkhard D. (Mount Kisco, NY); Takken, Todd E. (Mount Kisco, NY); Vranas, Pavlos M. (Bedford Hills, NY)

    2007-12-04T23:59:59.000Z

    In a massively parallel computing system having a plurality of nodes configured in m multi-dimensions, each node including a computing device, a method for routing packets towards their destination nodes is provided which includes generating at least one of a 2m plurality of compact bit vectors containing information derived from downstream nodes. A multilevel arbitration process in which downstream information stored in the compact vectors, such as link status information and fullness of downstream buffers, is used to determine a preferred direction and virtual channel for packet transmission. Preferred direction ranges are encoded and virtual channels are selected by examining the plurality of compact bit vectors. This dynamic routing method eliminates the necessity of routing tables, thus enhancing scalability of the switch.

  2. ''Smart'' watchdog safety switch

    DOE Patents [OSTI]

    Kronberg, J.W.

    1991-10-01T23:59:59.000Z

    A method and apparatus for monitoring a process having a periodic output so that the process equipment is not damaged in the event of a controller failure, comprising a low-pass and peak clipping filter, an event detector that generates an event pulse for each valid change in magnitude of the filtered periodic output, a timing pulse generator, a counter that increments upon receipt of any timing pulse and resets to zero on receipt of any event pulse, an alarm that alerts when the count reaches some preselected total count, and a set of relays that opens to stop power to process equipment. An interface module can be added to allow the switch to accept a variety of periodic output signals. 21 figures.

  3. Optimized scalable network switch

    DOE Patents [OSTI]

    Blumrich, Matthias A. (Ridgefield, CT); Chen, Dong (Croton on Hudson, NY); Coteus, Paul W. (Yorktown Heights, NY)

    2010-02-23T23:59:59.000Z

    In a massively parallel computing system having a plurality of nodes configured in m multi-dimensions, each node including a computing device, a method for routing packets towards their destination nodes is provided which includes generating at least one of a 2m plurality of compact bit vectors containing information derived from downstream nodes. A multilevel arbitration process in which downstream information stored in the compact vectors, such as link status information and fullness of downstream buffers, is used to determine a preferred direction and virtual channel for packet transmission. Preferred direction ranges are encoded and virtual channels are selected by examining the plurality of compact bit vectors. This dynamic routing method eliminates the necessity of routing tables, thus enhancing scalability of the switch.

  4. Alarm toe switch. [Patent application

    DOE Patents [OSTI]

    Ganyard, F.P.

    1980-11-18T23:59:59.000Z

    An alarm toe switch inserted within a shoe for energizing an alarm circuit in a covert manner includes an insole mounting pad into which a miniature reed switch is fixedly molded. An elongated slot perpendicular to the reed switch is formed in the bottom surface of the mounting pad. A permanent cylindrical magnet positioned in the forward portion of the slot with a diameter greater than the pad thickness causes a bump above the pad. A foam rubber block is also positioned in the slot rearwardly of the magnet and holds the magnet in normal inoperative relation. A non-magnetic support plate covers the slot and holds the magnet and foam rubber in the slot. The plate minimizes bending and frictional forces to improve movement of the magnet for reliable switch activation. The bump occupies the knuckle space beneath the big toe. When the big toe is scrunched rearwardly the magnet is moved within the slot relative to the reed switch, thus magnetically activating the switch. When toe pressure is released the foam rubber block forces the magnet back into normal inoperative position to deactivate the reed switch.

  5. Investigation on properties of ultrafast switching in a bulk gallium arsenide avalanche semiconductor switch

    SciTech Connect (OSTI)

    Hu, Long, E-mail: hulong-1226@126.com [Key Laboratory for Physical Electronics and Devices of the Ministry of Education, Xi'an Jiaotong University, Xi'an 710049 (China); Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024 (China); Su, Jiancang; Ding, Zhenjie; Hao, Qingsong; Yuan, Xuelin [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024 (China)

    2014-03-07T23:59:59.000Z

    Properties of ultrafast switching in a bulk gallium arsenide (GaAs) avalanche semiconductor switch based on semi-insulating wafer, triggered by an optical pulse, were analyzed using physics-based numerical simulations. It has been demonstrated that when a voltage with amplitude of 5.2?kV is applied, after an exciting optical pulse with energy of 1??J arrival, the structure with thickness of 650??m reaches a high conductivity state within 110 ps. Carriers are created due to photons absorption, and electrons and holes drift to anode and cathode terminals, respectively. Static ionizing domains appear both at anode and cathode terminals, and create impact-generated carriers which contribute to the formation of electron-hole plasma along entire channel. When the electric field in plasma region increases above the critical value (?4?kV/cm) at which the electrons drift velocity peaks, a domain comes into being. An increase in carrier concentration due to avalanche multiplication in the domains reduces the domain width and results in the formation of an additional domain as soon as the field outside the domains increases above ?4?kV/cm. The formation and evolution of multiple powerfully avalanching domains observed in the simulations are the physical reasons of ultrafast switching. The switch exhibits delayed breakdown with the characteristics affected by biased electric field, current density, and optical pulse energy. The dependence of threshold energy of the exciting optical pulse on the biased electric field is discussed.

  6. Flocking with Obstacle Avoidance in Switching Networks of Interconnected Vehicles

    E-Print Network [OSTI]

    Tanner, Herbert G.

    Flocking with Obstacle Avoidance in Switching Networks of Interconnected Vehicles Herbert G. Tanner Mechanical Engineering Department University of New Mexico Abstract--The paper introduces a set of nonsmooth- tivity requirements on the interconnection network can be relaxed due to the common objective. I

  7. Fast in-situ annealing stage coupled with EBSD : a suitable tool to observe quick recrystallization mechanisms

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    and cooling rates is not that crucial because EBSD data are directly acquired at high temperature recrystallization mechanisms N. Bozzolo* , S. Jacomet, and R.E. Log Mines ParisTech, CEMEF - Center of Materials developed to perform in-situ annealing in a SEM equipped with an EBSD system in order to study

  8. Current rectification, switching, polarons, and defects in molecular electronic devices

    E-Print Network [OSTI]

    A. M. Bratkovsky

    2006-11-06T23:59:59.000Z

    Devices for nano- and molecular size electronics are currently a focus of research aimed at an efficient current rectification and switching. A few generic molecular scale devices are reviewed here on the basis of first-principles and model approaches. Current rectification by (ballistic) molecular quantum dots can produce the rectification ratio ~100. Current switching due to conformational changes in the molecules is slow, on the order of a few kHz. Fast switching (~1THz) may be achieved, at least in principle, in a degenerate molecular quantum dot with strong coupling of electrons with vibrational excitations. We show that the mean-field approach fails to properly describe intrinsic molecular switching and present an exact solution to the problem. Defects in molecular films result in spurious peaks in conductance, apparent negative differential resistance, and may also lead to unusual temperature and bias dependence of current. The observed switching in many cases is_extrinsic_, caused by changes in molecule-electrode geometry, molecule reconfiguration, metallic filament formation through, and/or changing amount of disorder in a molecular film. We give experimental examples of telegraph "switching" and "hot spot" formation in the molecular films.

  9. Using X-ray observations to identify the particle acceleration mechanisms in VHE SNRs and "dark" VHE sources

    E-Print Network [OSTI]

    G. Phlhofer

    2007-10-17T23:59:59.000Z

    Very high energy (VHE) gamma-ray observations have proven to be very successful in localizing Galactic acceleration sites of VHE particles. Observations of shell-type supernova remnants have confirmed that particles are accelerated to VHE energies in supernova blast waves; the interpretation of the gamma-ray data in terms of hadronic or leptonic particle components in these objects relies nevertheless strongly on input from X-ray observations. The largest identified Galactic VHE source class consists of pulsar wind nebulae, as detected in X-rays. Many of the remaining VHE sources remain however unidentified until now. With X-ray observations of these enigmatic "dark" objects one hopes to solve the following questions: What is the astrophysical nature of these sources? Are they predominantly electron or hadron accelerators? And what is their contribution to the overall cosmic ray energy budget? The paper aims to provide an overview over the identification status of the Galactic VHE source population.

  10. Identifying Lights with their Switches Jayadev Misra

    E-Print Network [OSTI]

    Misra, Jayadev

    Identifying Lights with their Switches Jayadev Misra 09/07/2012 Problem Description Given are N switches and N lights where each switch controls exactly one light and each light is controlled by exactly of selecting some number of switches and turning them on, and, presumably, noting the lights that come

  11. Observed physical processes in mechanical tests of PBX9501 and recomendations for experiments to explore a possible plasticity/damage threshold

    SciTech Connect (OSTI)

    Buechler, Miles A. [Los Alamos National Laboratory

    2012-05-02T23:59:59.000Z

    This memo discusses observations that have been made in regards to a series of monotonic and cyclic uniaxial experiments performed on PBX9501 by Darla Thompson under Enhanced Surveilance Campaign support. These observations discussed in Section Cyclic compression observations strongly suggest the presence of viscoelastic, plastic, and damage phenomena in the mechanical response of the material. In Secton Uniaxial data analysis and observations methods are discussed for separating out the viscoelastic effects. A crude application of those methods suggests the possibility of a critical stress below which plasticity and damage may be negligible. The threshold should be explored because if it exists it will be an important feature of any constitutive model. Additionally, if the threshold exists then modifications of experimental methods may be feasible which could potentially simplify future experiments or provide higher quality data from those experiments. A set of experiments to explore the threshold stress are proposed in Section Exploratory tests program for identifying threshold stress.

  12. Optimal Switching with Quasi-Left-Continuous Switching Costs that Can Change Sign

    E-Print Network [OSTI]

    Glendinning, Paul

    for the switching problem in terms of interconnected Snell envelopes. We also prove the existence of an optimalOptimal Switching with Quasi-Left-Continuous Switching Costs that Can Change Sign Randall Martyr of Mathematics, The University of Manchester #12;Optimal switching with quasi-left-continuous switching costs

  13. Wide Bandgap Extrinsic Photoconductive Switches

    SciTech Connect (OSTI)

    Sullivan, J S

    2012-01-17T23:59:59.000Z

    Photoconductive semiconductor switches (PCSS) have been investigated since the late 1970s. Some devices have been developed that withstand tens of kilovolts and others that switch hundreds of amperes. However, no single device has been developed that can reliably withstand both high voltage and switch high current. Yet, photoconductive switches still hold the promise of reliable high voltage and high current operation with subnanosecond risetimes. Particularly since good quality, bulk, single crystal, wide bandgap semiconductor materials have recently become available. In this chapter we will review the basic operation of PCSS devices, status of PCSS devices and properties of the wide bandgap semiconductors 4H-SiC, 6H-SiC and 2H-GaN.

  14. Electronic logic for enhanced switch reliability

    DOE Patents [OSTI]

    Cooper, J.A.

    1984-01-20T23:59:59.000Z

    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.

  15. High PRF high current switch

    DOE Patents [OSTI]

    Moran, Stuart L. (Fredericksburg, VA); Hutcherson, R. Kenneth (College Park, MD)

    1990-03-27T23:59:59.000Z

    A triggerable, high voltage, high current, spark gap switch for use in pu power systems. The device comprises a pair of electrodes in a high pressure hydrogen environment that is triggered by introducing an arc between one electrode and a trigger pin. Unusually high repetition rates may be obtained by undervolting the switch, i.e., operating the trigger at voltages much below the self-breakdown voltage of the device.

  16. Plasma flow switch experiment on Procyon

    SciTech Connect (OSTI)

    Benage, J.F. Jr.; Bowers, R.; Peterson, D. [and others

    1995-09-01T23:59:59.000Z

    This report presents the results obtained from a series of plasma flow switch experiments done on the Procyon explosive pulse power generator. These experiments involved switching into a fixed inductance dummy load and also into a dynamic implosion load. The results indicated that the switch did fairly well at switching current into the load, but the results for the implosion are more ambiguous. The results are compared to calculations and the implications for future plasma flow switch work are discussed.

  17. Switchable diode effect and ferroelectric resistive switching in epitaxial BiFeO3 thin films

    E-Print Network [OSTI]

    Tian, Weidong

    Switchable diode effect and ferroelectric resistive switching in epitaxial BiFeO3 thin films Can observed in epitaxial multiferroic BiFeO3 BFO thin films. The forward direction of the rectifying current the switchable diode effect and the ferroelectric resistive switching in epitaxially BFO thin films. BFO thin

  18. Retention and switching kinetics of protonated gate field effect transistors

    SciTech Connect (OSTI)

    DEVINE,R.A.B.; HERRERA,GILBERT V.

    2000-05-23T23:59:59.000Z

    The switching and memory retention time has been measured in 50 {micro}m gatelength pseudo-non-volatile memory MOSFETS containing, protonated 40 nm gate oxides. Times of the order of 3.3 seconds are observed for fields of 3 MV cm{sup {minus}1}. The retention time with protons placed either at the gate oxide/substrate or gate oxide/gate electrode interfaces is found to better than 96{percent} after 5,000 seconds. Measurement of the time dependence of the source-drain current during switching provides clear evidence for the presence of dispersive proton transport through the gate oxide.

  19. Retention and Switching Kinetics of Protonated Gate Field Effect Transistors

    SciTech Connect (OSTI)

    DEVINE,R.A.B.; HERRERA,GILBERT V.

    2000-06-27T23:59:59.000Z

    The switching and memory retention time has been measured in 50 {micro}m gatelength pseudo-non-volatile memory MOSFETs containing, protonated 40 nm gate oxides. Times of the order of 3.3 seconds are observed for fields of 3 MV cm{sup {minus}1}. The retention time with protons placed either at the gate oxide/substrate or gate oxide/gate electrode interfaces is found to better than 96% after 5,000 seconds. Measurement of the time dependence of the source-drain current during switching provides clear evidence for the presence of dispersive proton transport through the gate oxide.

  20. Factorial Switching Kalman Filters for Condition Monitoring in Neonatal Intensive Care

    E-Print Network [OSTI]

    Williams, Christopher; Quinn, J.; McIntosh, N.

    The observed physiological dynamics of an infant receiving intensive care are affected by many possible factors, including interventions to the baby, the operation of the monitoring equipment and the state of health. The Factorial Switching Kalman...

  1. Switch for serial or parallel communication networks

    DOE Patents [OSTI]

    Crosette, Dario B. (DeSoto, TX)

    1994-01-01T23:59:59.000Z

    A communication switch apparatus and a method for use in a geographically extensive serial, parallel or hybrid communication network linking a multi-processor or parallel processing system has a very low software processing overhead in order to accommodate random burst of high density data. Associated with each processor is a communication switch. A data source and a data destination, a sensor suite or robot for example, may also be associated with a switch. The configuration of the switches in the network are coordinated through a master processor node and depends on the operational phase of the multi-processor network: data acquisition, data processing, and data exchange. The master processor node passes information on the state to be assumed by each switch to the processor node associated with the switch. The processor node then operates a series of multi-state switches internal to each communication switch. The communication switch does not parse and interpret communication protocol and message routing information. During a data acquisition phase, the communication switch couples sensors producing data to the processor node associated with the switch, to a downlink destination on the communications network, or to both. It also may couple an uplink data source to its processor node. During the data exchange phase, the switch couples its processor node or an uplink data source to a downlink destination (which may include a processor node or a robot), or couples an uplink source to its processor node and its processor node to a downlink destination.

  2. Switch for serial or parallel communication networks

    DOE Patents [OSTI]

    Crosette, D.B.

    1994-07-19T23:59:59.000Z

    A communication switch apparatus and a method for use in a geographically extensive serial, parallel or hybrid communication network linking a multi-processor or parallel processing system has a very low software processing overhead in order to accommodate random burst of high density data. Associated with each processor is a communication switch. A data source and a data destination, a sensor suite or robot for example, may also be associated with a switch. The configuration of the switches in the network are coordinated through a master processor node and depends on the operational phase of the multi-processor network: data acquisition, data processing, and data exchange. The master processor node passes information on the state to be assumed by each switch to the processor node associated with the switch. The processor node then operates a series of multi-state switches internal to each communication switch. The communication switch does not parse and interpret communication protocol and message routing information. During a data acquisition phase, the communication switch couples sensors producing data to the processor node associated with the switch, to a downlink destination on the communications network, or to both. It also may couple an uplink data source to its processor node. During the data exchange phase, the switch couples its processor node or an uplink data source to a downlink destination (which may include a processor node or a robot), or couples an uplink source to its processor node and its processor node to a downlink destination. 9 figs.

  3. High voltage MOSFET switching circuit

    DOE Patents [OSTI]

    McEwan, T.E.

    1994-07-26T23:59:59.000Z

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

  4. High voltage MOSFET switching circuit

    DOE Patents [OSTI]

    McEwan, Thomas E. (Livermore, CA)

    1994-01-01T23:59:59.000Z

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

  5. Electrical contact resistance degradation of a hot-switched simulated metal MEMS contact.

    SciTech Connect (OSTI)

    Dugger, Michael Thomas; Dickrell, Daniel John, III

    2005-03-01T23:59:59.000Z

    Electrical contact resistance testing was performed by hot-switching a simulated gold-platinum metal microelectromechanical systems contact. The experimental objective was to determine the sensitivity of the contact resistance degradation to current level and environment. The contact resistance increased sharply after 100 hot-switched cycles in air. Hot-switching at a reduced current and in nitrogen atmosphere curtailed contact resistance degradation by several orders of magnitude. The mechanism responsible for the resistance degradation was found to be arc-induced decomposition of adsorbed surface contaminants.

  6. Observation of chaotic beats in a driven memristive Chua's circuit

    E-Print Network [OSTI]

    A. Ishaq Ahamed; K. Srinivasan; K. Murali; M. Lakshmanan

    2010-08-27T23:59:59.000Z

    In this paper, a time varying resistive circuit realising the action of an active three segment piecewise linear flux controlled memristor is proposed. Using this as the nonlinearity, a driven Chua's circuit is implemented. The phenomenon of chaotic beats in this circuit is observed for a suitable choice of parameters. The memristor acts as a chaotically time varying resistor (CTVR), switching between a less conductive OFF state and a more conductive ON state. This chaotic switching is governed by the dynamics of the driven Chua's circuit of which the memristor is an integral part. The occurrence of beats is essentially due to the interaction of the memristor aided self oscillations of the circuit and the external driving sinusoidal forcing. Upon slight tuning/detuning of the frequencies of the memristor switching and that of the external force, constructive and destructive interferences occur leading to revivals and collapses in amplitudes of the circuit variables, which we refer as chaotic beats. Numerical simulations and Multisim modelling as well as statistical analyses have been carried out to observe as well as to understand and verify the mechanism leading to chaotic beats.

  7. Low-profile high-voltage compact gas switch

    SciTech Connect (OSTI)

    Goerz, D.A.; Wilson, M.J.; Speer, R.D.

    1997-06-30T23:59:59.000Z

    This paper discusses the development and testing of a low-profile, high-voltage, spark-gap switch designed to be closely coupled with other components into an integrated high-energy pulsed-power source. The switch is designed to operate at 100 kV using SF6 gas pressurized to less than 0.7 MPa. The volume of the switch cavity region is less than 1.5 cm3, and the field stress along the gas-dielectric interface is as high as 130 kV/cm. The dielectric switch body has a low profile that is only I -cm tall at its greatest extent and nominally 2-mm thick over most of its area. This design achieves a very low inductance of less than 5 nH, but results in field stresses exceeding 500 kV/cm in the dielectric material. Field modeling was done to determine the appropriate shape for the highly stressed insulator and electrodes, and special manufacturing techniques were employed to mitigate the usual mechanisms that induce breakdown and failure in solid dielectrics. Static breakdown tests verified that the switch operates satisfactorily at 100 kV levels. The unit has been characterized with different shaped electrodes having nominal gap spacings of 2.0, 2.5, and 3.0 mm. The relationship between self-break voltage and operating pressure agrees well with published data on gas properties, accounting for the field enhancements of the electrode shapes being used. Capacitor discharge tests in a low inductance test fixture exhibited peak currents up to 25 kA with characteristic frequencies of the ringdown circuit ranging from 10 to 20 MHz. The ringdown waveforms and scaling of measured parameters agree well with circuit modeling of the switch and test fixture. Repetitive operation has been demonstrated at moderate rep-rates up to 15 Hz, limited by the power supply being used. Preliminary tests to evaluate lifetime of the compact switch assembly have been encouraging. In one case, after more than 7,000 high-current ringdown tests with approximately 30 C of total charge transferred, the switch continued to operate satisfactorily with no apparent tracking or deterioration of the insulator.

  8. Networks of coupled circuits: From a versatile toggle switch to collective coherent behavior

    E-Print Network [OSTI]

    Darka Labavi?; Hildegard Meyer-Ortmanns

    2014-09-16T23:59:59.000Z

    We study the versatile performance of networks of coupled circuits. Each of these circuits is composed of a positive and a negative feedback loop in a motif that is frequently found in genetic and neural networks. When two of these circuits are coupled with mutual repression, the system can function as a toggle switch. The variety of its states can be controlled by two parameters as we demonstrate by a detailed bifurcation analysis. In the bistable regimes switches between the coexisting attractors can be induced by noise. When we couple larger sets of these units, we numerically observe collective coherent modes of individual fixed-point and limit-cycle behavior. It is there the monotonic change of a single bifurcation parameter that allows to control the onset and arrest of the synchronized oscillations. This mechanism may play a role in biological applications, in particular in connection with the segmentation clock. While tuning the bifurcation parameter, also a variety of transient patterns emerges upon approaching the stationary states, in particular a self-organized pacemaker in a completely uniformly equipped ensemble, so that the symmetry breaking happens dynamically.

  9. Secure videoconferencing equipment switching system and method

    DOE Patents [OSTI]

    Hansen, Michael E. (Livermore, CA)

    2009-01-13T23:59:59.000Z

    A switching system and method are provided to facilitate use of videoconference facilities over a plurality of security levels. The system includes a switch coupled to a plurality of codecs and communication networks. Audio/Visual peripheral components are connected to the switch. The switch couples control and data signals between the Audio/Visual peripheral components and one but nor both of the plurality of codecs. The switch additionally couples communication networks of the appropriate security level to each of the codecs. In this manner, a videoconferencing facility is provided for use on both secure and non-secure networks.

  10. Large aperture optical switching devices

    SciTech Connect (OSTI)

    Goldhar, J.; Henesian, M.A.

    1983-12-12T23:59:59.000Z

    We have developed a new approach to constructing large aperture optical switches for next generation inertial confinement fusion lasers. A transparent plasma electrode formed in low pressure ionized gas acts as a conductive coating to allow the uniform charging of the optical faces of an electro-optic material. In this manner large electric fields can be applied longitudinally to large aperture, high aspect ratio Pockels cells. We propose a four-electrode geometry to create the necessary high conductivity plasma sheets, and have demonstrated fast (less than 10 nsec) switching in a 5x5 cm aperture KD*P Pockels cell with such a design. Detaid modelling of Pockels cell performance with plasma electrodes has been carried out for 15 and 30 cm aperture designs.

  11. Switch for Good Community Program

    SciTech Connect (OSTI)

    Crawford, Tabitha; Amran, Martha

    2013-11-19T23:59:59.000Z

    Switch4Good is an energy-savings program that helps residents reduce consumption from behavior changes; it was co-developed by Balfour Beatty Military Housing Management (BB) and WattzOn in Phase I of this grant. The program was offered at 11 Navy bases. Three customer engagement strategies were evaluated, and it was found that Digital Nudges (a combination of monthly consumption statements with frequent messaging via text or email) was most cost-effective.

  12. ASYMPTOTIC OBSERVERS FOR DISCRETE-TIME SWITCHED LINEAR

    E-Print Network [OSTI]

    Egerstedt, Magnus

    - essary. 2 In Alessandri and Coletta (2001), it was 2 The example at the end of this paper illustrates

  13. Planning in partially-observable switching-mode continuous domains

    E-Print Network [OSTI]

    Brunskill, Emma

    Continuous-state POMDPs provide a natural representation for a variety of tasks, including many in robotics. However, most existing parametric continuous-state POMDP approaches are limited by their reliance on a single ...

  14. Phase controlled light switching at low power levels

    E-Print Network [OSTI]

    Hoonsoo Kang; Gessler Hernandez; Jiepeng Zhang; Yifu Zhu

    2005-10-05T23:59:59.000Z

    We report experimental observations of interference between three-photon and one-photon excitations, and phase control of light attenuation/transmission in a four-level system. Either constructive interference or destructive interference can be obtained by varying the phase and/or frequency of a weak control laser. The interference enables absorptive switching of one field by another field at different frequencies and ultra-low light levels.

  15. A magnetically switched kicker for proton extraction

    SciTech Connect (OSTI)

    Dinkel, J.; Biggs, J.

    1989-03-01T23:59:59.000Z

    The application of magnetic current amplification and switching techniques to the generation of precise high current pulses for switching magnets is described. The square loop characteristic of Metglas tape wound cores at high excitation levels provides excellent switching characteristics for microsecond pulses. The rugged and passive nature of this type pulser makes it possible to locate the final stages of amplification at the load for maximum efficiency. 12 refs., 8 figs.

  16. Feedback Mechanism for Microtubule Length Regulation by Stathmin Gradients

    E-Print Network [OSTI]

    Maria Zeitz; Jan Kierfeld

    2014-12-09T23:59:59.000Z

    We formulate and analyze a theoretical model for the regulation of microtubule (MT) polymerization dynamics by the signaling proteins Rac1 and stathmin. In cells, the MT growth rate is inhibited by cytosolic stathmin, which, in turn, is inactivated by Rac1. Growing MTs activate Rac1 at the cell edge, which closes a positive feedback loop. We investigate both tubulin sequestering and catastrophe promotion as mechanisms for MT growth inhibition by stathmin. For a homogeneous stathmin concentration in the absence of Rac1, we find a switch-like regulation of the MT mean length by stathmin. For constitutively active Rac1 at the cell edge, stathmin is deactivated locally, which establishes a spatial gradient of active stathmin. In this gradient, we find a stationary bimodal MT length distributions for both mechanisms of MT growth inhibition by stathmin. One subpopulation of the bimodal length distribution can be identified with fast growing and long pioneering MTs in the region near the cell edge, which have been observed experimentally. The feedback loop is closed through Rac1 activation by MTs. For tubulin sequestering by stathmin, this establishes a bistable switch with two stable states: one stable state corresponds to upregulated MT mean length and bimodal MT length distributions, i.e., pioneering MTs; the other stable state corresponds to an interrupted feedback with short MTs. Stochastic effects as well as external perturbations can trigger switching events. For catastrophe promoting stathmin we do not find bistability.

  17. Multi-megavolt low jitter multistage switch

    DOE Patents [OSTI]

    Humphreys, D.R.; Penn, K.J. Jr.

    1985-06-19T23:59:59.000Z

    It is one object of the present invention to provide a multistage switch capable of holding off numerous megavolts, until triggered, from a particle beam accelerator of the type used for inertial confinement fusion. The invention provides a multistage switch having low timing jitter and capable of producing multiple spark channels for spreading current over a wider area to reduce electrode damage and increase switch lifetime. The switch has fairly uniform electric fields and a short spark gap for laser triggering and is engineered to prevent insulator breakdowns.

  18. High-index-contrast electromechanical optical switches

    E-Print Network [OSTI]

    Bryant, Reginald (Reginald Eugene), 1978-

    2011-01-01T23:59:59.000Z

    System developers are looking to replace protocol-dependent, bandwidth-limited optical networks with intelligent optically-transparent integrated photonic networks. Several electromechanical optical switches are explored ...

  19. Multiprocessor switch with selective pairing

    DOE Patents [OSTI]

    Gara, Alan; Gschwind, Michael K; Salapura, Valentina

    2014-03-11T23:59:59.000Z

    System, method and computer program product for a multiprocessing system to offer selective pairing of processor cores for increased processing reliability. A selective pairing facility is provided that selectively connects, i.e., pairs, multiple microprocessor or processor cores to provide one highly reliable thread (or thread group). Each paired microprocessor or processor cores that provide one highly reliable thread for high-reliability connect with a system components such as a memory "nest" (or memory hierarchy), an optional system controller, and optional interrupt controller, optional I/O or peripheral devices, etc. The memory nest is attached to a selective pairing facility via a switch or a bus

  20. Optical switching system and method

    DOE Patents [OSTI]

    Ranganathan, Radha (N. Tonawanda, NY); Gal, Michael (Engadine, AU); Taylor, P. Craig (Salt Lake City, UT)

    1992-01-01T23:59:59.000Z

    An optically bistable device is disclosed. The device includes a uniformly thick layer of amorphous silicon to constitute a Fabry-Perot chamber positioned to provide a target area for a probe beam. The probe beam has a maximum energy less than the energy band gap of the amorphous semiconductor. In a preferred embodiment, a multilayer dielectric mirror is positioned on the Fabry-Perot chamber to increase the finesse of switching of the device. The index of refraction of the amorphous material is thermally altered to alter the transmission of the probe beam.

  1. Microwave-triggered laser switch

    DOE Patents [OSTI]

    Piltch, Martin S. (Los Alamos, NM)

    1984-01-01T23:59:59.000Z

    A high-repetition rate switch for delivering short duration, high-power electrical pulses from a pulsed-charged dc power supply. The present invention utilizes a microwave-generating device such as a magnetron that is capable of producing high-power pulses at high-pulse repetition rates and fast-pulse risetimes for long periods with high reliability. The rail-gap electrodes provide a large surface area that reduces induction effects and minimizes electrode erosion. Additionally, breakdown is initiated in a continuous geometric fashion that also increases operating lifetime of the device.

  2. Laser-triggered vacuum switch

    DOE Patents [OSTI]

    Brannon, Paul J. (Albuquerque, NM); Cowgill, Donald F. (Danville, CA)

    1990-01-01T23:59:59.000Z

    A laser-triggered vacuum switch has a material such as a alkali metal halide on the cathode electrode for thermally activated field emission of electrons and ions upon interaction with a laser beam, the material being in contact with the cathode with a surface facing the discharge gap. The material is preferably a mixture of KCl and Ti powders. The laser may either shine directly on the material, preferably through a hole in the anode, or be directed to the material over a fiber optic cable.

  3. Microwave-triggered laser switch

    DOE Patents [OSTI]

    Piltch, M.S.

    1982-05-19T23:59:59.000Z

    A high-repetition rate switch is described for delivering short duration, high-powered electrical pulses from a pulsed-charged dc power supply. The present invention utilizes a microwave-generating device such as a magnetron that is capable of producing high-power pulses at high-pulse repetition rates and fast-pulse risetimes for long periods with high reliability. The rail-gap electrodes provide a large surface area that reduces induction effects and minimizes electrode erosion. Additionally, breakdown is initiated in a continuous geometric fashion that also increases operating lifetime of the device.

  4. Switch LLC | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro Industries PvtStratosolar Jump to:Holdings Co08.0 - Warehouses 73.0 -SwiftSwissvale,Switch LLC

  5. Analysis of the Ultra-fast Switching Dynamics in a Hybrid MOSFET/Driver

    SciTech Connect (OSTI)

    Tang, T.; Burkhart, C.; /SLAC

    2011-08-17T23:59:59.000Z

    The turn-on dynamics of a power MOSFET during ultra-fast, {approx} ns, switching are discussed in this paper. The testing was performed using a custom hybrid MOSFET/Driver module, which was fabricated by directly assembling die-form components, power MOSFET and drivers, on a printed circuit board. By using die-form components, the hybrid approach substantially reduces parasitic inductance, which facilitates ultra-fast switching. The measured turn on time of the hybrid module with a resistive load is 1.2 ns with an applied voltage of 1000 V and drain current of 33 A. Detailed analysis of the switching waveforms reveals that switching behavior must be interpreted differently in the ultra-fast regime. For example, the gate threshold voltage to turn on the device is observed to increase as the switching time decreases. Further analysis and simulation of MOSFET switching behavior shows that the minimum turn on time scales with the product of the drain-source on resistance and drain-source capacitance, R{sub DS(on)}C{sub OSS}. This information will be useful in power MOSFET selection and gate driver design for ultra-fast switching applications.

  6. Ames Lab 101: Ultrafast Magnetic Switching

    ScienceCinema (OSTI)

    Jigang Wang

    2013-06-05T23:59:59.000Z

    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.

  7. PBC: A Partially Buffered Crossbar Packet Switch

    E-Print Network [OSTI]

    Kuzmanov, Georgi

    fabric is widely used as the interconnect of high-performance packet switches due to its low cost-performance packet switches because of its low cost and scalability. As a result, the vast majority and scalability. There are two main variants of the crossbar fabric: unbuffered and internally buffered. On one

  8. Asynchronous vs Synchronous Input-Queued Switches

    E-Print Network [OSTI]

    of high-performance switches. 1 INTRODUCTION A vast technical literature exists on input-queued (IQ to performance losses in comparison with synchronous cell switching, these losses are limited, and may be smaller than the losses due to the above-mentioned segmenta- tion/reassembly overheads. In real scenarios

  9. The Generalized Switched Accounting or Conduction

    E-Print Network [OSTI]

    The Generalized Switched Accounting or Conduction Isaac Zafrany1 1 Technical Support Avant modeling and simulation of PWM converters was extended to include conduction losses. The method covers losses due to the inductor's resistance and due to the voltage drops across the switch and the diode

  10. Seismic switch for strong motion measurement

    DOE Patents [OSTI]

    Harben, Philip E. (Oakley, CA); Rodgers, Peter W. (Santa Barbara, CA); Ewert, Daniel W. (Patterson, CA)

    1995-01-01T23:59:59.000Z

    A seismic switching device that has an input signal from an existing microseismic station seismometer and a signal from a strong motion measuring instrument. The seismic switch monitors the signal level of the strong motion instrument and passes the seismometer signal to the station data telemetry and recording systems. When the strong motion instrument signal level exceeds a user set threshold level, the seismometer signal is switched out and the strong motion signal is passed to the telemetry system. The amount of time the strong motion signal is passed before switching back to the seismometer signal is user controlled between 1 and 15 seconds. If the threshold level is exceeded during a switch time period, the length of time is extended from that instant by one user set time period.

  11. Seismic switch for strong motion measurement

    DOE Patents [OSTI]

    Harben, P.E.; Rodgers, P.W.; Ewert, D.W.

    1995-05-30T23:59:59.000Z

    A seismic switching device is described that has an input signal from an existing microseismic station seismometer and a signal from a strong motion measuring instrument. The seismic switch monitors the signal level of the strong motion instrument and passes the seismometer signal to the station data telemetry and recording systems. When the strong motion instrument signal level exceeds a user set threshold level, the seismometer signal is switched out and the strong motion signal is passed to the telemetry system. The amount of time the strong motion signal is passed before switching back to the seismometer signal is user controlled between 1 and 15 seconds. If the threshold level is exceeded during a switch time period, the length of time is extended from that instant by one user set time period. 11 figs.

  12. Modeling Combustion Control for High Power Diesel Mode Switching...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Combustion Control for High Power Diesel Mode Switching Modeling Combustion Control for High Power Diesel Mode Switching Poster presentation given at the 16th Directions in...

  13. Robust Diamond-Based RF Switch Yields Enhanced Communication...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Robust Diamond-Based RF Switch Yields Enhanced Communication Capabilities Technology available for licesning: A radio frequency (RF) microelectromechanical system (MEMS) switch...

  14. Dynamic Switching of the Spin Circulation in Tapered Magnetic...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Dynamic Switching of the Spin Circulation in Tapered Magnetic Nanodisks Dynamic Switching of the Spin Circulation in Tapered Magnetic Nanodisks Print Monday, 22 April 2013 12:09...

  15. Flipping the switch on magnetism in strontium titanate

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Flipping the switch on magnetism in strontium titanate Flipping the switch on magnetism in strontium titanate Researchers have found a way to magnetize this material using light,...

  16. Switch on Clean Energy Activity Book | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    Switch on Clean Energy Activity Book Switch on Clean Energy Activity Book Games and activity book about energy efficiency and renewable energy technologies for kids....

  17. A Quantum Biological Switch Based on Superradiance Transitions

    E-Print Network [OSTI]

    D. Ferrari; G. L. Celardo; G. P. Berman; R. T. Sayre; F. Borgonovi

    2013-07-05T23:59:59.000Z

    A linear chain of connected electron sites with two asymmetric sinks, one attached to each end, is used as a simple model of quantum electron transfer in photosynthetic bio-complexes. For a symmetric initial population in the middle of the chain, it is expected that electron transfer is mainly directed towards the strongest coupled sink. However, we show that quantum effects radically change this intuitive "classical" mechanism, so that electron transfer can occur through the weaker coupled sink with maximal efficiency. Using this capability, we show how to design a quantum switch that can transfer an electron to the left or right branch of the chain, by changing the coupling to the sinks. The operational principles of this quantum device can be understood in terms of superradiance transitions and subradiant states. This switching, being a pure quantum effect, can be used as a witness of wave--like behaviour of excitations in molecular chains. When realistic data are used for the photosystem II reaction center, this quantum biological switch is shown to retain its reliability, even at room temperature.

  18. Single Molecule Switches and Molecular Self-Assembly: Low Temperature STM Investigations and Manipulations

    SciTech Connect (OSTI)

    Iancu, Violeta

    2006-08-01T23:59:59.000Z

    This dissertation is devoted to single molecule investigations and manipulations of two porphyrin-based molecules, chlorophyll-a and Co-popphyrin. The molecules are absorbed on metallic substrates and studied at low temperatures using a scanning tunneling microscope. The electronic, structural and mechanical properties of the molecules are investigated in detail with atomic level precision. Chlorophyll-a is the key ingredient in photosynthesis processes while Co-porphyrin is a magnetic molecule that represents the recent emerging field of molecular spintronics. Using the scanning tunneling microscope tip and the substrate as electrodes, and the molecules as active ingredients, single molecule switches made of these two molecules are demonstrated. The first switch, a multiple and reversible mechanical switch, is realized by using chlorophyll-a where the energy transfer of a single tunneling electron is used to rotate a C-C bond of the molecule's tail on a Au(111) surface. Here, the det

  19. Critical analysis and remedy of switching failures in straintronic logic using Bennett clocking in the presence of thermal fluctuations

    SciTech Connect (OSTI)

    Roy, Kuntal, E-mail: royk@purdue.edu [School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)] [School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)

    2014-01-06T23:59:59.000Z

    Straintronic logic is a promising platform for beyond Moore's law computing. Using Bennett clocking mechanism, information can propagate through an array of strain-mediated multiferroic nanomagnets, exploiting the dipolar coupling between the magnets without having to physically interconnect them. Here, we perform a critical analysis of switching failures, i.e., error in information propagation due to thermal fluctuations through a chain of such straintronic devices. We solved stochastic Landau-Lifshitz-Gilbert equation considering room-temperature thermal perturbations and show that magnetization switching may fail due to inherent magnetization dynamics accompanied by thermally broadened switching delay distribution. Avenues available to circumvent such issue are proposed.

  20. Recovering the Heat Dissipated by the Digital Switching Equipment

    E-Print Network [OSTI]

    Karasseferian, V. V.; Desjardins, R.

    1983-01-01T23:59:59.000Z

    irrespective of its usage capa city. For example, a digital switcher dissipa tes heat at a rate of 25 to 35 watts per sq. ft. as compared to 3 or 4 watts per sq. ft. for the electro mechanical switching equipment. This type of equipment is being installed... to the atrrosphere by the cool ing plant servicing the digital switcher, to heat other parts of the building. Energy prices have not, in the past, diffe red considerably from the average inflation rate of the economy as a whole. This situation crea ted little...

  1. Statistical physics of a model binary genetic switch with linear feedback

    E-Print Network [OSTI]

    Paolo Visco; Rosalind J. Allen; Martin R. Evans

    2009-03-31T23:59:59.000Z

    We study the statistical properties of a simple genetic regulatory network that provides heterogeneity within a population of cells. This network consists of a binary genetic switch in which stochastic flipping between the two switch states is mediated by a "flipping" enzyme. Feedback between the switch state and the flipping rate is provided by a linear feedback mechanism: the flipping enzyme is only produced in the on switch state and the switching rate depends linearly on the copy number of the enzyme. This work generalises the model of [Phys. Rev. Lett., 101, 118104] to a broader class of linear feedback systems. We present a complete analytical solution for the steady-state statistics of the number of enzyme molecules in the on and off states, for the general case where the enzyme can mediate flipping in either direction. For this general case we also solve for the flip time distribution, making a connection to first passage and persistence problems in statistical physics. We show that the statistics of the model are non-Poissonian, leading to a peak in the flip time distribution. The occurrence of such a peak is analysed as a function of the parameter space. We present a new relation between the flip time distributions measured for two relevant choices of initial condition. We also introduce a new correlation measure to show that this model can exhibit long-lived temporal correlations, thus providing a primitive form of cellular memory. Motivated by DNA replication as well as by evolutionary mechanisms involving gene duplication, we study the case of two switches in the same cell. This results in correlations between the two switches; these can either positive or negative depending on the parameter regime.

  2. Switch-like reprogramming of gene expression after fusion of multinucleate plasmodial cells of two Physarum polycephalum sporulation mutants

    SciTech Connect (OSTI)

    Walter, Pauline; Hoffmann, Xenia-Katharina; Ebeling, Britta; Haas, Markus; Marwan, Wolfgang, E-mail: wolfgang.marwan@ovgu.de

    2013-05-24T23:59:59.000Z

    Highlights: We investigate reprogramming of gene expression in multinucleate single cells. Cells of two differentiation control mutants are fused. Fused cells proceed to alternative gene expression patterns. The population of nuclei damps stochastic fluctuations in gene expression. Dynamic processes of cellular reprogramming can be observed by repeated sampling of a cell. -- Abstract: Nonlinear dynamic processes involving the differential regulation of transcription factors are considered to impact the reprogramming of stem cells, germ cells, and somatic cells. Here, we fused two multinucleate plasmodial cells of Physarum polycephalum mutants defective in different sporulation control genes while being in different physiological states. The resulting heterokaryons established one of two significantly different expression patterns of marker genes while the plasmodial halves that were fused to each other synchronized spontaneously. Spontaneous synchronization suggests that switch-like control mechanisms spread over and finally control the entire plasmodium as a result of cytoplasmic mixing. Regulatory molecules due to the large volume of the vigorously streaming cytoplasm will define concentrations in acting on the population of nuclei and in the global setting of switches. Mixing of a large cytoplasmic volume is expected to damp stochasticity when individual nuclei deliver certain RNAs at low copy number into the cytoplasm. We conclude that spontaneous synchronization, the damping of molecular noise in gene expression by the large cytoplasmic volume, and the option to take multiple macroscopic samples from the same plasmodium provide unique options for studying the dynamics of cellular reprogramming at the single cell level.

  3. Atomic Collapse Observed

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Scientists Observe Atomic Collapse State Quantum Mechanics Prediction Confirmed in Graphene Using NERSC's Hopper April 26, 2013 | Tags: Hopper, Materials Science Contact: Linda...

  4. Coordination and Lock-In: Competition with Switching Costs

    E-Print Network [OSTI]

    Sadoulet, Elisabeth

    Coordination and Lock-In: Competition with Switching Costs and Network E ects Part II of IV Switching Costs Section December 2004 the latest version of this paper, and related material, will be at www Switching Costs and Competition 2.1 Introduction A consumer faces a switching cost between sellers when

  5. Theory and inference for a Markov switching GARCH model

    E-Print Network [OSTI]

    Nesterov, Yurii

    2007/55 Theory and inference for a Markov switching GARCH model Luc Bauwens, Arie Preminger and Jeroen V.K. Rombouts #12;CORE DISCUSSION PAPER 2007/55 Theory and inference for a Markov switching GARCH-switching GARCH model (MS-GARCH) wherein the conditional mean and variance switch in time from one GARCH process

  6. High-Q silica zipper cavity for optical radiation pressure driven MOMS switch

    SciTech Connect (OSTI)

    Tetsumoto, Tomohiro; Tanabe, Takasumi, E-mail: takasumi@elec.keio.ac.jp [Department of Electronics and Electrical Engineering, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi Kohoku, Yokohama 223-8522 (Japan)

    2014-07-15T23:59:59.000Z

    We design a silica zipper cavity that has high optical and mechanical Q (quality factor) values and demonstrate numerically the feasibility of a radiation pressure driven micro opto-mechanical system (MOMS) directional switch. The silica zipper cavity has an optical Q of 4.0 10{sup 4} and an effective mode volume V{sub mode} of 0.67?{sup 3} when the gap between two cavities is 34 nm. The mechanical Q (Q{sub m}) is determined by thermo-elastic damping and is 2.0 10{sup 6} in a vacuum at room temperature. The opto-mechanical coupling rate g{sub OM} is as high as 100 GHz/nm, which allows us to move the directional cavity-waveguide system and switch 1550-nm light with 770-nm light by controlling the radiation pressure.

  7. Optimal control of controllable switched systems

    E-Print Network [OSTI]

    Rinehart, Michael David

    2005-01-01T23:59:59.000Z

    Many of the existing techniques for controlling switched systems either require the solution to a complex optimization problem or significant sacrifices to either stability or performance to offer practical controllers. ...

  8. Value iteration for (switched) homogeneous systems

    E-Print Network [OSTI]

    Dahleh, Munther A.

    In this note, we prove that dynamic programming value iteration converges uniformly for discrete-time homogeneous systems and continuous-time switched homogeneous systems. For discrete-time homogeneous systems, rather than ...

  9. Clause chaining, switch reference and coordination

    E-Print Network [OSTI]

    Nonato, Rafael

    2014-01-01T23:59:59.000Z

    In this thesis I ponder over a constellation of phenomena that revolve around switch reference and coordination, drawing mainly on their instantiation in Kisedje (Je, Brazil). I start by investigating Klsedje's case system. ...

  10. Monetary Interventions in Crowdsourcing Task Switching

    E-Print Network [OSTI]

    Chen, Yiling

    intervention treatments No Bonus Switch Bonus Repetition Bonus 15 experimental Accuracy Innately compete with each other Performance-contingent bonuses Receive bonus in a task if the answer is correct and the reaction time

  11. Industrial Fuel Switching - Emerging NGL Opportunities

    E-Print Network [OSTI]

    Cascone, R.

    2004-01-01T23:59:59.000Z

    INDUSTRIAL FUEL SWITCHING - EMERGING NGL OPPORTUNITIES Ron Cascone Manager Special Projects, Utilities and Environmental Nexant, Inc. White Plains, NY ABSTRACT Removing butanes and pentanes from gasoline to meet local... feedstocks, convert them to alternative fuels, or sell them as heating fuels. Industrial fuel users can switch from fuel oil, natural gas or LPG for short periods to these clean and/or more economic fuels. Current regulations will necessitate removing...

  12. High speed transfer switch with 50 kA and 50 kV

    SciTech Connect (OSTI)

    Reass, W.A.; Kasik, R.J.; Wilds, W.A.

    1989-01-01T23:59:59.000Z

    This paper gives the mechanical design and electrical parameters of a pneumatically operated transfer switch. This design is used to switch 3-second 50-kA current pulses, and is easily capable of 75 kA operation (2 {times} 10{sup 10} I{sup 2}t); with water-cooled versions capable of 20 kA continuously. Although the switch is not specifically designed to make or break 50 kA, it is provided with auxiliary Elkonite arcing contacts have proven their value in protecting the main electrodes even under repetitive (50 kA) fault conditions. Included in this presentation will be the results of extensive life testing and associated criteria. 6 figs., 1 tab.

  13. Switching surface polarization of atomic force microscopy probe utilizing photoisomerization of photochromic molecules

    SciTech Connect (OSTI)

    Aburaya, Yoshihiro; Nomura, Hikaru; Kageshima, Masami; Naitoh, Yoshitaka; Li, Yan Jun; Sugawara, Yasuhiro [Department of Applied Physics, Graduate School of Engineering, Osaka University 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan)

    2011-03-15T23:59:59.000Z

    An attempt to develop an atomic force microscopy (AFM) probe with optically switchable polarization is described. Modification with a single molecular layer of photochromic molecules was attempted onto a Si substrate that is a prototype for a probe surface. Polarization switching caused by alternate irradiation of UV and visible lights were detected using the electrostatic force?>spectroscopy (EFS) technique. Si substrates modified with spiropyran and azobenzene exhibited reversible polarization switching that caused changes in CPD of about 100 and 50 mV, respectively. Modification with spiropyran was also attempted onto a Si probe and resulted in a CPD change of about 100 mV. It was confirmed that modification of an AFM probe or substrate with a single molecular layer of photochromic molecules can generate surface polarization switching of a mechanically detectable level.

  14. Efficient tunable switch from slow light to fast light in quantum opto-electromechanical system

    E-Print Network [OSTI]

    M. Javed Akram; Khalid Naseer; Farhan Saif

    2015-03-05T23:59:59.000Z

    The control of slow and fast light propagation, in the probe transmission in a single experiment, is a challenging task. This type of control can only be achieved through highly nonlinear interactions and additional interfering pathway(s), which is therefore seldom reported. Here, we devise a scheme in which slow light, and a tunable switch from slow light to fast light can be achieved in the probe transmission based on a hybrid setup, which is composed of an optical cavity with two charged nano mechanical resonators (MRs). The two MRs are electrostatically coupled via tunable Coulomb coupling strength ($g_{c}$) making a quantum opto-electromechanical system (QOEMS). The parameter $g_{c}$ that couples the two MRs can be switched on and off by controlling the bias voltages on the MRs, and acts as a tunable switch that allows the propagation of transmitted probe field as slow light ($g_{c} \

  15. Resistive switching and threshold switching behaviors in La{sub 0.1}Bi{sub 0.9}Fe{sub 1-x}Co{sub x}O{sub 3} ceramics

    SciTech Connect (OSTI)

    Wang, S. Y.; Qiu, Xue; Feng, Yu; Hou, X. G.; Yu, D. S.; Li, D. J. [College of Physics and Electronic Information Science, Tianjin Normal University, Tianjin 300074 (China); Liu, W. F. [Tianjin Key laboratory of Low Dimensional Materials Physics and Preparing Technology, Faculty of Science, Tianjin University, Tianjin 300072 (China); Gao, J. [Department of Physics, the University of Hong Kong, Pokfulam Road (Hong Kong)

    2012-08-01T23:59:59.000Z

    The effects of cobalt doping on the electrical conductivity of La{sub 0.1}Bi{sub 0.9}Fe{sub 1-x}Co{sub x}O{sub 3} (LBFCO, x = 0, 0.01, 0.03) ceramics were investigated. It is found that the leakage current increases with cobalt dopant concentration in LBFCO. On the application of bias voltage LBFCO ceramics with cobalt doping exhibits resistive switching effects at room temperature and threshold switching effects at elevated temperatures (50 Degree-Sign C and 80 Degree-Sign C). X-ray photoelectron spectroscopy of LBFCO ceramics show that cobalt dopant is bivalent as an acceptor, which induces an enhancement of oxygen vacancy concentration in LBFCO ceramics. Possible mechanisms for both resistive switching and threshold switching effects are discussed on the basis of the interplay of bound ferroelectric charges and mobile charged defects.

  16. Physical process Mechanical mechanisms

    E-Print Network [OSTI]

    Berlin,Technische Universitt

    1 Physical process Generation Mechanical mechanisms F = ma Electric/Magnetic mechanisms F = Bil Fluid dynamic/Hydraulic mechanisms q, p, ij Thermal/Optical #12;2 Source unit

  17. Sub-mesoscale coastal eddies observed by high frequency radar: A new mechanism for delivering nutrients to kelp forests in the Southern

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    nutrients to kelp forests in the Southern California Bight Corinne J. Bassin and Libe Washburn Institute radar: A new mechanism for delivering nutrients to kelp forests in the Southern California Bight] Internal waves are one such process that transport nutrients and larvae to kelp forests on the inner shelf

  18. Video Switching in the Panopto Editor Video Switching in the Panopto Editor

    E-Print Network [OSTI]

    Benos, Panayiotis "Takis"

    Video Switching in the Panopto Editor Video Switching in the Panopto Editor In My Pitt Video (Panopto) you can control and edit which video streams the viewer sees by editing individual streams in the My Pitt Video (Panopto) Editor. Editing the primary video source will edit on all streams, editing

  19. Fundamental science investigations to develop a 6-MV laser triggered gas switch for ZR: first annual report.

    SciTech Connect (OSTI)

    Warne, Larry Kevin; Van Den Avyle, James A.; Lehr, Jane Marie; Rose, David (Voss Scientific, Albuquerque, NM); Krompholz, Hermann G. (Texas Tech University, Lubbock, TX); Vela, Russell (Texas Tech University, Lubbock, TX); Jorgenson, Roy Eberhardt; Timoshkin, Igor (University of Strathclyde, Glasgow, Scotland); Woodworth, Joseph Ray; Prestwich, Kenneth Randel (Voss Scientific, Albuquerque, NM); Krile, John (Texas Tech University, Lubbock, TX); Given, Martin (University of Strathclyde, Glasgow, Scotland); McKee, G. Randall; Rosenthal, Stephen Edgar; Struve, Kenneth William; Welch, Dale Robert (Voss Scientific, Albuquerque, NM); Benwell, Andrew L. (University of Missouri-Columbia, Columbia, Missouri); Kovaleski, Scott (University of Missouri-Columbia, Columbia, Missouri); LeChien, Keith, R.; Johnson, David (Titan Pulse Sciences Division); Fouracre, R.A. (University of Strathclyde, Glasgow, Scotland); Yeckel, Chris (University of Missouri-Columbia, Columbia, Missouri); Wakeland, Peter Eric (Ktech Corporation, Albuquerque, NM); Miller, A. R. (Titan Pulse Sciences Division); Hodge, Keith Conquest (Ktech Corporation, Albuquerque, NM); Pasik, Michael Francis; Savage, Mark Edward; Maenchen, John Eric; Curry, Randy D. (University of Missouri-Columbia, Columbia, Missouri); Feltz, Greg (Ktech Corporation, Albuquerque, NM); Bliss, David Emery; MacGregor, Scott (University of Strathclyde, Glasgow, Scotland); Corley, J. P. (Ktech Corporation, Albuquerque, NM); Anaya, Victor (Ktech Corporation, Albuquerque, NM); Wallace, Zachariah (Ktech Corporation, Albuquerque, NM); Thoma, Carsten (Voss Scientific, Albuquerque, NM); Neuber, Andreas. (Texas Tech University, Lubbock, TX)

    2007-03-01T23:59:59.000Z

    In October 2005, an intensive three-year Laser Triggered Gas Switch (LTGS) development program was initiated to investigate and solve observed performance and reliability issues with the LTGS for ZR. The approach taken has been one of mission-focused research: to revisit and reassess the design, to establish a fundamental understanding of LTGS operation and failure modes, and to test evolving operational hypotheses. This effort is aimed toward deploying an initial switch for ZR in 2007, on supporting rolling upgrades to ZR as the technology can be developed, and to prepare with scientific understanding for the even higher voltage switches anticipated needed for future high-yield accelerators. The ZR LTGS was identified as a potential area of concern quite early, but since initial assessments performed on a simplified Switch Test Bed (STB) at 5 MV showed 300-shot lifetimes on multiple switch builds, this component was judged acceptable. When the Z{sub 20} engineering module was brought online in October 2003 frequent flashovers of the plastic switch envelope were observed at the increased stresses required to compensate for the programmatically increased ZR load inductance. As of October 2006, there have been 1423 Z{sub 20} shots assessing a variety of LTGS designs. Numerous incremental and fundamental switch design modifications have been investigated. As we continue to investigate the LTGS, the basic science of plastic surface tracking, laser triggering, cascade breakdown, and optics degradation remain high-priority mission-focused research topics. Significant progress has been made and, while the switch does not yet achieve design requirements, we are on the path to develop successively better switches for rolling upgrade improvements to ZR. This report summarizes the work performed in FY 2006 by the large team. A high-level summary is followed by detailed individual topical reports.

  20. Mechanical Engineering Department 04 November 2013

    E-Print Network [OSTI]

    Furlong, Cosme

    Department Light Sources Light emitting diode (LED) When a light-emitting diode is forward biased (switched a p-n junction #12;Mechanical Engineering Department Light Sources Light emitting diode (LED the p-n junction #12;Mechanical Engineering Department Light Sources Light emitting diode (LED) #12

  1. Engineered materials for all-optical helicity-dependent magnetic switching

    E-Print Network [OSTI]

    Fainman, Yeshaiahu

    Engineered materials for all-optical helicity-dependent magnetic switching S. Mangin1,2 *, M we explore the optical manipulation of the magnetization in engineered magnetic materials. We of engineered magnetic materials and devices. We demonstrate that AO-HDS can be observed not only in selected RE

  2. Discrete-time mode switching control with application to a PMSM position servo system

    E-Print Network [OSTI]

    Benmei, Chen

    Discrete-time mode switching control with application to a PMSM position servo system Guoyang Cheng control Servo systems Permanent magnet synchronous motor (PMSM) Observer Nonlinearities a b s t r a c results on a permanent magnet synchronous motor (PMSM) servo system verify that the proposed control

  3. Magnetic switch for reactor control rod. [LMFBR

    DOE Patents [OSTI]

    Germer, J.H.

    1982-09-30T23:59:59.000Z

    A magnetic reed switch assembly is described for activating an electromagnetic grapple utilized to hold a control rod in position above a reactor core. In normal operation the magnetic field of a permanent magnet is short-circuited by a magnetic shunt, diverting the magnetic field away from the reed switch. The magnetic shunt is made of a material having a Curie-point at the desired release temperature. Above that temperature the material loses its ferromagnetic properties, and the magnetic path is diverted to the reed switch which closes and short-circuits the control circuit for the control rod electro-magnetic grapple which allows the control rod to drop into the reactor core for controlling the reactivity of the core.

  4. Magnetic switch for reactor control rod

    DOE Patents [OSTI]

    Germer, John H. (San Jose, CA)

    1986-01-01T23:59:59.000Z

    A magnetic reed switch assembly for activating an electromagnetic grapple utilized to hold a control rod in position above a reactor core. In normal operation the magnetic field of a permanent magnet is short-circuited by a magnetic shunt, diverting the magnetic field away from the reed switch. The magnetic shunt is made of a material having a Curie-point at the desired release temperature. Above that temperature the material loses its ferromagnetic properties, and the magnetic path is diverted to the reed switch which closes and short-circuits the control circuit for the control rod electromagnetic grapple which allows the control rod to drop into the reactor core for controlling the reactivity of the core.

  5. Compact high voltage solid state switch

    DOE Patents [OSTI]

    Glidden, Steven C.

    2003-09-23T23:59:59.000Z

    A compact, solid state, high voltage switch capable of high conduction current with a high rate of current risetime (high di/dt) that can be used to replace thyratrons in existing and new applications. The switch has multiple thyristors packaged in a single enclosure. Each thyristor has its own gate drive circuit that circuit obtains its energy from the energy that is being switched in the main circuit. The gate drives are triggered with a low voltage, low current pulse isolated by a small inexpensive transformer. The gate circuits can also be triggered with an optical signal, eliminating the trigger transformer altogether. This approach makes it easier to connect many thyristors in series to obtain the hold off voltages of greater than 80 kV.

  6. Resistive switching phenomena of tungsten nitride thin films with excellent CMOS compatibility

    SciTech Connect (OSTI)

    Hong, Seok Man; Kim, Hee-Dong; An, Ho-Myoung; Kim, Tae Geun, E-mail: tgkim1@korea.ac.kr

    2013-12-15T23:59:59.000Z

    Graphical abstract: - Highlights: The resistive switching characteristics of WN{sub x} thin films. Excellent CMOS compatibility WN{sub x} films as a resistive switching material. Resistive switching mechanism revealed trap-controlled space charge limited conduction. Good endurance and retention properties over 10{sup 5} cycles, and 10{sup 5} s, respectively - Abstract: We report the resistive switching (RS) characteristics of tungsten nitride (WN{sub x}) thin films with excellent complementary metal-oxide-semiconductor (CMOS) compatibility. A Ti/WN{sub x}/Pt memory cell clearly shows bipolar RS behaviors at a low voltage of approximately 2.2 V. The dominant conduction mechanisms at low and high resistance states were verified by Ohmic behavior and trap-controlled space-charge-limited conduction, respectively. A conducting filament model by a redox reaction explains the RS behavior in WN{sub x} films. We also demonstrate the memory characteristics during pulse operation, including a high endurance over >10{sup 5} cycles and a long retention time of >10{sup 5} s.

  7. Optically triggered high voltage switch network and method for switching a high voltage

    DOE Patents [OSTI]

    El-Sharkawi, Mohamed A. (Renton, WA); Andexler, George (Everett, WA); Silberkleit, Lee I. (Mountlake Terrace, WA)

    1993-01-19T23:59:59.000Z

    An optically triggered solid state switch and method for switching a high voltage electrical current. A plurality of solid state switches (350) are connected in series for controlling electrical current flow between a compensation capacitor (112) and ground in a reactive power compensator (50, 50') that monitors the voltage and current flowing through each of three distribution lines (52a, 52b and 52c), which are supplying three-phase power to one or more inductive loads. An optical transmitter (100) controlled by the reactive power compensation system produces light pulses that are conveyed over optical fibers (102) to a switch driver (110') that includes a plurality of series connected optical triger circuits (288). Each of the optical trigger circuits controls a pair of the solid state switches and includes a plurality of series connected resistors (294, 326, 330, and 334) that equalize or balance the potential across the plurality of trigger circuits. The trigger circuits are connected to one of the distribution lines through a trigger capacitor (340). In each switch driver, the light signals activate a phototransistor (300) so that an electrical current flows from one of the energy reservoir capacitors through a pulse transformer (306) in the trigger circuit, producing gate signals that turn on the pair of serially connected solid state switches (350).

  8. Manufacturing fuel-switching capability, 1988

    SciTech Connect (OSTI)

    Not Available

    1991-09-01T23:59:59.000Z

    Historically, about one-third of all energy consumed in the United States has been used by manufacturers. About one-quarter of manufacturing energy is used as feedstocks and raw material inputs that are converted into nonenergy products; the remainder is used for its energy content. During 1988, the most recent year for which data are available, manufacturers consumed 15.5 quadrillion British thermal units (Btu) of energy to produce heat and power and to generate electricity. The manufacturing sector also has widespread capabilities to switch from one fuel to another for either economic or emergency reasons. There are numerous ways to define fuel switching. For the purposes of the Manufacturing Energy Consumption Survey (MECS), fuel switching is defined as the capability to substitute one energy source for another within 30 days with no significant modifications to the fuel-consuming equipment, while keeping production constant. Fuel-switching capability allows manufacturers substantial flexibility in choosing their mix of energy sources. The consumption of a given energy source can be maximized if all possible switching into that energy source takes place. The estimates in this report are based on data collected on the 1988 Manufacturing Energy Consumption Survey (MECS), Forms 846 (A through C). The EIA conducts this national sample survey of manufacturing energy consumption on a triennial basis. The MECS is the only comprehensive source of national-level data on energy-related information for the manufacturing industries. The MECS was first conducted in 1986 to collect data for 1985. This report presents information on the fuel-switching capabilities of manufacturers in 1988. This report is the second of a series based on the 1988 MECS. 8 figs., 31 tabs.

  9. A Taxonomy of Rerouting in Circuit-Switched Networks

    E-Print Network [OSTI]

    Wong, Eric Wing-Ming

    A Taxonomy of Rerouting in Circuit-Switched Networks Eric W. M. Wong and Andy K. M. Chan, City presents a taxonomy of rerouting in circuit- switched networks showing the various ways rerouting can

  10. Carbon nano-relays for low power switching

    E-Print Network [OSTI]

    Milaninia, Kaveh Mehdi

    2009-01-01T23:59:59.000Z

    In this thesis two unique carbon based nanoelectromechanical switches or carbon nano-relays are demonstrated as a toolkit for investigating NEMs based low power switching. The first is a vertical carbon nano-relay, consisting ...

  11. Effect of oxyfluorinated multi-walled carbon nanotube additives on positive temperature coefficient/negative temperature coefficient behavior in high-density polyethylene polymeric switches

    SciTech Connect (OSTI)

    Bai, Byong Chol [Department of Green Energy Technology, Chungnam National University, Daejeon 305-764 (Korea, Republic of) [Department of Green Energy Technology, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Department of Fine Chemical Engineering and Applied Chemistry, BK21-E2M, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Kang, Seok Chang; Im, Ji Sun [Department of Fine Chemical Engineering and Applied Chemistry, BK21-E2M, Chungnam National University, Daejeon 305-764 (Korea, Republic of)] [Department of Fine Chemical Engineering and Applied Chemistry, BK21-E2M, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Lee, Se Hyun [Department of Electrical and Electronic Engineering, Korea Polytechnic IV College, Daejeon 300-702 (Korea, Republic of)] [Department of Electrical and Electronic Engineering, Korea Polytechnic IV College, Daejeon 300-702 (Korea, Republic of); Lee, Young-Seak, E-mail: youngslee@cnu.ac.kr [Department of Green Energy Technology, Chungnam National University, Daejeon 305-764 (Korea, Republic of) [Department of Green Energy Technology, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Department of Fine Chemical Engineering and Applied Chemistry, BK21-E2M, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

    2011-09-15T23:59:59.000Z

    Graphical abstract: The electrical properties of MWCNT-filled HDPE polymeric switches and their effect on oxyfluorination. Highlights: {yields} Oxyfluorinated MWCNTs were used to reduce the PTC/NTC phenomenon in MWCNT-filled HDPE polymeric switches. {yields} Electron mobility is difficult in MWCNT particles when the number of oxygen functional groups (C-O, C=O) increases by oxyfluorination. {yields} A mechanism of improved electrical properties of oxyfluorinated MWCNT-filled HDPE polymeric switches was suggested. -- Abstract: Multi-walled carbon nanotubes (MWCNTs) were embedded into high-density polyethylene (HDPE) to improve the electrical properties of HDPE polymeric switches. The MWCNT surfaces were modified by oxyfluorination to improve their positive temperature coefficient (PTC) and negative temperature coefficient (NTC) behaviors in HDPE polymeric switches. HDPE polymeric switches exhibit poor electron mobility between MWCNT particles when the number of oxygen functional groups is increased by oxyfluorination. Thus, the PTC intensity of HDPE polymeric switches was increased by the destruction of the electrical conductivity network. The oxyfluorination of MWCNTs also leads to weak NTC behavior in the MWCNT-filled HDPE polymeric switches. This result is attributed to the reduction of the mutual attraction between the MWCNT particles at the melting temperature of HDPE, which results from a decrease in the surface free energy of the C-F bond in MWCNT particles.

  12. Optimal switching control design for polynomial systems: an LMI approach

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    Optimal switching control design for polynomial systems: an LMI approach Didier Henrion1 formulate the switching design problem as an optimal control problem which is then relaxed to a linear to the design of optimal switching sequences for polynomial dynamical systems with state constraints. We

  13. Energy and Switch Area Optimizations for FPGA Global Routing Architectures

    E-Print Network [OSTI]

    Fainman, Yeshaiahu

    13 Energy and Switch Area Optimizations for FPGA Global Routing Architectures YI ZHU, YUANFANG HU and wire style optimization, to reduce the energy and switch area of FPGA global routing architectures achieve up to 10% to 15% energy savings and up to 20% switch area savings in average for a set of seven

  14. A Brain-Switch using Riemannian Geometry A. Barachant1

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    A Brain-Switch using Riemannian Geometry A. Barachant1 , S. Bonnet1 , M. Congedo2 , C. Jutten2 1 the issue of asynchronous brain-switch. The detection of a specific brain pattern from the ongoing EEG-time EEG segments contain all the desired information. Such a brain-switch is valuable as it is easy to set

  15. Optimal Control of Switched Hybrid Systems: A Brief Survey

    E-Print Network [OSTI]

    Antsaklis, Panos

    Optimal Control of Switched Hybrid Systems: A Brief Survey Technical Report of the ISIS Group FengZhu and Panos J. Antsaklis, "Optimal Control of Switched Hybrid Systems: a Brief Survey," ISIS Technical Report ISIS-2013-007, July 2013. #12;1 Optimal Control of Switched Hybrid Systems: A Brief Survey

  16. Optimal Control of Switched Hybrid Systems: A Brief Survey

    E-Print Network [OSTI]

    Antsaklis, Panos

    Optimal Control of Switched Hybrid Systems: A Brief Survey Technical Report of the ISIS Group;1 Optimal Control of Switched Hybrid Systems: A Brief Survey Abstract This paper surveys recent results in the field of optimal control of hybrid and switched systems. We summarize recent results that use different

  17. Optimal Control of Switched Hybrid Systems: A Brief Survey

    E-Print Network [OSTI]

    Antsaklis, Panos

    Optimal Control of Switched Hybrid Systems: A Brief Survey Technical Report of the ISIS Group;1 Optimal Control of Switched Hybrid Systems: A Brief Survey Feng Zhu and Panos J. Antsaklis Department a few. The problem of determining optimal control laws for hybrid systems and in particular for switched

  18. Heritable Stochastic Switching Revealed by Single-Cell Genealogy

    E-Print Network [OSTI]

    van Oudenaarden, Alexander

    Heritable Stochastic Switching Revealed by Single-Cell Genealogy Benjamin B. Kaufmann1,2[ , Qiong switching revealed by single-cell genealogy. PLoS Biol 5(9): e239. doi:10.1371/ journal.pbio.0050239 measurements of phenotype stability, switching, and herit- ability are rare, both because detailed genealogical

  19. An Optical Interconnection Architecture for Large Packet Switches

    E-Print Network [OSTI]

    reliability concerns due to the large number of active components in the switch fabric. Routers with optical to consider the limits imposed by electronic technology; in particular, it must take into account power not only solutions that make use of optics inside electronic switches but that also switching architectures

  20. RF-MEMS capacitive switches with high reliability

    DOE Patents [OSTI]

    Goldsmith, Charles L.; Auciello, Orlando H.; Carlisle, John A.; Sampath, Suresh; Sumant, Anirudha V.; Carpick, Robert W.; Hwang, James; Mancini, Derrick C.; Gudeman, Chris

    2013-09-03T23:59:59.000Z

    A reliable long life RF-MEMS capacitive switch is provided with a dielectric layer comprising a "fast discharge diamond dielectric layer" and enabling rapid switch recovery, dielectric layer charging and discharging that is efficient and effective to enable RF-MEMS switch operation to greater than or equal to 100 billion cycles.

  1. Thermionic converter in load-switching mode

    SciTech Connect (OSTI)

    Mendel'baum, M.A.; Es'kov, V.D.

    1983-01-01T23:59:59.000Z

    An electrical equivalent circuit is proposed for a thermionic electrogenerating element. It is suitable for calculation of transients in load-switching mode. Formulas are given for estimating circuit parameters. A sample numerical calculation is given for the transient between no-load and short-circuit regimes. The results may be employed to identify experimental data in the frequency domain.

  2. Optically initiated silicon carbide high voltage switch

    DOE Patents [OSTI]

    Caporaso, George J. (Livermore, CA); Sampayan, Stephen E. (Manteca, CA); Sullivan, James S. (Livermore, CA); Sanders; David M. (Livermore, CA)

    2011-02-22T23:59:59.000Z

    An improved photoconductive switch having a SiC or other wide band gap substrate material, such as GaAs and field-grading liners composed of preferably SiN formed on the substrate adjacent the electrode perimeters or adjacent the substrate perimeters for grading the electric fields.

  3. Smart Grid Application of Optimal Transmission Switching

    E-Print Network [OSTI]

    Ferris, Michael C.

    ;6 Introduction continued Electric Transmission Network Flow Problem Optimal Power Flow (OPF) AlternatingSmart Grid Application of Optimal Transmission Switching By, Kory W. Hedman, et al.* University (Professor, UC Berkeley) #12;2 Motivation Co-optimize transmission topology and generation dispatch

  4. All-optical discrete vortex switch

    SciTech Connect (OSTI)

    Desyatnikov, Anton S. [Nonlinear Physics Center, Research School of Physics and Engineering, Australian National University, Canberra, ACT 0200 (Australia); Dennis, Mark R. [H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Ferrando, Albert [Interdisciplinary Modeling Group, InterTech and Departament d'Optica, Universitat de Valencia, E-46100 Burjassot (Spain)

    2011-06-15T23:59:59.000Z

    We introduce discrete vortex solitons and vortex breathers in circular arrays of nonlinear waveguides. The simplest vortex breather in a four-waveguide coupler is a nonlinear dynamic state changing its topological charge between +1 and -1 periodically during propagation. We find the stability domain for this solution and suggest an all-optical vortex switching scheme.

  5. A distributed bioremediation problem with modal switching

    E-Print Network [OSTI]

    Seidman, Thomas I.

    8/8/'98 A distributed bioremediation problem with modal switching Thomas I. Seidman Department conversion to an innocuous form: cometabolism) -- i.e., bioremediation. For some further exposition of the nature and significance of bioremediation as a practical application we refer the reader, e.g., to [2

  6. A thermodynamic switch for chromosome colocalization

    E-Print Network [OSTI]

    M. Nicodemi; B. Panning; A. Prisco

    2008-09-27T23:59:59.000Z

    A general model for the early recognition and colocalization of homologous DNA sequences is proposed. We show, on a thermodynamic ground, how the distance between two homologous DNA sequences is spontaneously regulated by the concentration and affinity of diffusible mediators binding them, which act as a switch between two phases corresponding to independence or colocalization of pairing regions.

  7. Switching dynamics in cholesteric blue phases

    E-Print Network [OSTI]

    A. Tiribocchi; G. Gonnella; D. Marenduzzo; E. Orlandini

    2011-03-30T23:59:59.000Z

    Blue phases are networks of disclination lines, which occur in cholesteric liquid crystals near the transition to the isotropic phase. They have recently been used for the new generation of fast switching liquid crystal displays. Here we study numerically the steady states and switching hydrodynamics of blue phase I (BPI) and blue phase II (BPII) cells subjected to an electric field. When the field is on, there are three regimes: for very weak fields (and strong anchoring at the boundaries) the blue phases are almost unaffected, for intermediate fields the disclinations twist (for BPI) and unzip (for BPII), whereas for very large voltages the network dissolves in the bulk of the cell. Interestingly, we find that a BPII cell can recover its original structure when the field is switched off, whereas a BPI cell is found to be trapped more easily into metastable configurations. The kinetic pathways followed during switching on and off entails dramatic reorganisation of the disclination networks. We also discuss the effect of changing the director field anchoring at the boundary planes and of varying the direction of the applied field.

  8. Ternary gas mixture for diffuse discharge switch

    DOE Patents [OSTI]

    Christophorou, Loucas G. (Oak Ridge, TN); Hunter, Scott R. (Oak Ridge, TN)

    1988-01-01T23:59:59.000Z

    A new diffuse discharge gas switch wherein a mixture of gases is used to take advantage of desirable properties of the respective gases. There is a conducting gas, an insulating gas, and a third gas that has low ionization energy resulting in a net increase in the number of electrons available to produce a current.

  9. Isolated and soft-switched power converter

    DOE Patents [OSTI]

    Peng, Fang Zheng (Knoxville, TN); Adams, Donald Joe (Knoxville, TN)

    2002-01-01T23:59:59.000Z

    An isolated and soft-switched power converter is used for DC/DC and DC/DC/AC power conversion. The power converter includes two resonant tank circuits coupled back-to-back through an isolation transformer. Each resonant tank circuit includes a pair of resonant capacitors connected in series as a resonant leg, a pair of tank capacitors connected in series as a tank leg, and a pair of switching devices with anti-parallel clamping diodes coupled in series as resonant switches and clamping devices for the resonant leg. The power converter is well suited for DC/DC and DC/DC/AC power conversion applications in which high-voltage isolation, DC to DC voltage boost, bidirectional power flow, and a minimal number of conventional switching components are important design objectives. For example, the power converter is especially well suited to electric vehicle applications and load-side electric generation and storage systems, and other applications in which these objectives are important. The power converter may be used for many different applications, including electric vehicles, hybrid combustion/electric vehicles, fuel-cell powered vehicles with low-voltage starting, remote power sources utilizing low-voltage DC power sources, such as photovoltaics and others, electric power backup systems, and load-side electric storage and generation systems.

  10. Asynchronous vs Synchronous Input-Queued Switches

    E-Print Network [OSTI]

    for the design of high-performance switches. I. INTRODUCTION A vast technical literature exists on input. Unfortunately the technical literature has largely neglected this situation, and concentrated the attention throughput, or to simpler scheduling. Even when the asynchronous operation leads to performance losses

  11. Interconnecting network for switching data packets and method for switching data packets

    DOE Patents [OSTI]

    Benner, Alan Frederic; Minkenberg, Cyriel Johan Agnes; Stunkel, Craig Brian

    2010-05-25T23:59:59.000Z

    The interconnecting network for switching data packets, having data and flow control information, comprises a local packet switch element (S1) with local input buffers (I(1,1) . . . I(1,y)) for buffering the incoming data packets, a remote packet switch element (S2) with remote input buffers (I(2,1) . . . I(2,y)) for buffering the incoming data packets, and data lines (L) for interconnecting the local and the remote packet switch elements (S1, S2). The interconnecting network further comprises a local and a remote arbiter (A1, A2) which are connected via control lines (CL) to the input buffers (I(1,1) . . . I(1,y), I(2,1) . . . I(2,y)), and which are formed such that they can provide that the flow control information is transmitted via the data lines (L) and the control lines (CL).

  12. A compact plasmonic MOS-based 2x2 electro-optic switch

    E-Print Network [OSTI]

    Ye, Chenran; Soref, Richard A; Sorger, Volker J

    2015-01-01T23:59:59.000Z

    We report on a three-waveguide electro-optic switch for compact photonic integrated circuits and data routing applications. The device features a plasmonic metal-oxide-semiconductor (MOS) mode for enhanced light-matter-interactions. The switching mechanism originates from a capacitor-like design where the refractive index of the active medium, Indium-Tin-Oxide, is altered via shifting the plasma frequency due to carrier accumulation inside the waveguide-based MOS structure. This light manipulation mechanism controls the transmission direction of transverse magnetic polarized light into either a CROSS or BAR waveguide port. The extinction ratio of 18 dB (7) dB for the CROSS (BAR) state, respectively, is achieved via a gating voltage bias. The ultrafast broadband fJ/bit device allows for seamless integration with Siliconon- Insulator platforms to for low-cost manufacturing.

  13. An Element of Determinism in a Stochastic Flagellar Motor Switch

    E-Print Network [OSTI]

    Xie, Li; Wu, Xiao-Lun

    2015-01-01T23:59:59.000Z

    Marine bacterium Vibrio alginolyticus uses a single polar flagellum to navigate in an aqueous environment. Similar to Escherichia coli cells, the polar flagellar motor has two states; when the motor is counter-clockwise, the cell swims forward and when the motor is clockwise, the cell swims backward. V. alginolyticus also incorporates a direction randomization step at the start of the forward swimming interval by flicking its flagellum. To gain an understanding on how the polar flagellar motor switch is regulated, distributions of the forward $\\Delta_{f}$ and backward $\\Delta_{b}$ intervals are investigated herein. We found that the steady-state probability density functions, $P(\\Delta_{f})$ and $P(\\Delta_{b})$, of freely swimming bacteria are strongly peaked at a finite time, suggesting that the motor switch is not Poissonian. The short-time inhibition is sufficiently strong and long lasting, i.e., several hundred milliseconds for both intervals, which is readily observed and characterized. Treating motor re...

  14. Float level switch for a nuclear power plant containment vessel

    DOE Patents [OSTI]

    Powell, J.G.

    1993-11-16T23:59:59.000Z

    This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel. 1 figures.

  15. Float level switch for a nuclear power plant containment vessel

    DOE Patents [OSTI]

    Powell, James G. (Clifton Park, NY)

    1993-01-01T23:59:59.000Z

    This invention is a float level switch used to sense rise or drop in water level in a containment vessel of a nuclear power plant during a loss of coolant accident. The essential components of the device are a guide tube, a reed switch inside the guide tube, a float containing a magnetic portion that activates a reed switch, and metal-sheathed, ceramic-insulated conductors connecting the reed switch to a monitoring system outside the containment vessel. Special materials and special sealing techniques prevent failure of components and allow the float level switch to be connected to a monitoring system outside the containment vessel.

  16. Toward tunable RNA thermo-switches for temperature dependent gene expression

    E-Print Network [OSTI]

    Oscar M. J. A. Stassen; Ruud J. J. Jorna; Bastiaan A. van den Berg; Rad Haghi; Farzad Ehtemam; Steven M. Flipse; Marco J. L. de Groot; Janine A. Kiers; I. Emrah Nikerel; Domenico Bellomo

    2011-09-25T23:59:59.000Z

    RNA thermometers are mRNA strands with a temperature dependent secondary structure: depending on the spatial conformation, the mRNA strand can get translated (on-state) or can be inaccessible for ribosomes binding (off-state). These have been found in a number of microorganisms (mainly pathogens), where they are used to adaptively regulate the gene expression, in response to changes in the environmental temperature. Besides naturally occurring RNA thermometers, synthetic RNA thermometers have been recently designed by modifying their natural counterparts (Hofacker et al., 2003). The newly designed RNA thermometers are simpler, and exhibit a sharper switching between off- and on-states. However, the proposed trial-and-error design procedure has not been algorithmically formalized, and the switching temperature is rigidly determined by the natural RNA thermometer used as template for the design. We developed a general algorithmic procedure (consensus distribution) for the design of RNA thermo-switches with a tunable switching temperature that can be decided in advance by the designer. A software tool with a user friendly GUI has been written to automate the design of RNA thermo-switches with a desired threshold temperature. Starting from a natural template, a new RNA thermometer has been designed by our method for a new desired threshold temperature of 32C. The designed RNA thermo-switch has been experimentally validated by using it to control the expression of lucifarase. A 9.2 fold increase of luminescence has been observed between 30C and 37C, whereas between 20C and 30C the luminescence increase is less than 3-fold. This work represents a first step towards the design of flexible and tunable RNA thermometers that can be used for a precise control of gene expression without the need of external chemicals and possibly for temperature measurements at a nano-scale resolution.

  17. High-speed, sub-pull-in voltage MEMS switching.

    SciTech Connect (OSTI)

    Spahn, Olga Blum; Brewer, Steven; Olsson, Roy H.; Bogart, Gregory R.; Luck, David L.; Watts, Michael R.; Shaw, Michael J.; Nielson, Gregory N.; Resnick, Paul James; Tigges, Christopher P.; Grossetete, Grant David

    2008-01-01T23:59:59.000Z

    We have proposed and demonstrated MEMS switching devices that take advantage of the dynamic behavior of the MEMS devices to provide lower voltage actuation and higher switching speeds. We have explored the theory behind these switching techniques and have demonstrated these techniques in a range of devices including MEMS micromirror devices and in-plane parallel plate MEMS switches. In both devices we have demonstrated switching speeds under one microsecond which has essentially been a firm limit in MEMS switching. We also developed low-loss silicon waveguide technology and the ability to incorporate high-permittivity dielectric materials with MEMS. The successful development of these technologies have generated a number of new projects and have increased both the MEMS switching and optics capabilities of Sandia National Laboratories.

  18. Navigation System for Ground Vehicles using Temporally Interconnected Observers

    E-Print Network [OSTI]

    navigation technique for an automotive vehicle. This method involves several observers, each designed for a particular type of trajectory, that are turned on and off according to a switching policy. Each observer of observer design of vehicular systems. A typical example of such practices1 is found in the navigation

  19. Flexoelectric switching in cholesteric blue phases

    E-Print Network [OSTI]

    A. Tiribocchi; M. E. Cates; G. Gonnella; D. Marenduzzo; E. Orlandini

    2013-03-25T23:59:59.000Z

    We present computer simulations of the response of a flexoelectric blue phase network, either in bulk or under confinement, to an applied field. We find a transition in the bulk between the blue phase I disclination network and a parallel array of disclinations along the direction of the applied field. Upon switching off the field, the system is unable to reconstruct the original blue phase but gets stuck in a metastable phase. Blue phase II is comparatively much less affected by the field. In confined samples, the anchoring at the walls and the geometry of the device lead to the stabilisation of further structures, including field-aligned disclination loops, splayed nematic patterns, and yet more metastable states. Our results are relevant to the understanding of the switching dynamics for a class of new, "superstable", blue phases which are composed of bimesogenic liquid crystals, as these materials combine anomalously large flexoelectric coefficients, and low or near-zero dielectric anisotropy.

  20. Gas mixture for diffuse-discharge switch

    DOE Patents [OSTI]

    Christophorou, L.G.; Carter, J.G.; Hunter, S.R.

    1982-08-31T23:59:59.000Z

    Gaseous medium in a diffuse-discharge switch of a high-energy pulse generator is formed of argon combined with a compound selected from the group consisting of CF/sub 4/, C/sub 2/F/sub 6/, C/sub 3/F/sub 8/, n-C/sub 4/F/sub 10/, WF/sub 6/, (CF/sub 3/)/sub 2/S and (CF/sub 3/)/sub 2/O.

  1. Thermionic switched self-actuating reactor shutdown system

    DOE Patents [OSTI]

    Barrus, Donald M. (San Jose, CA); Shires, Charles D. (San Jose, CA); Brummond, William A. (Livermore, CA)

    1989-01-01T23:59:59.000Z

    A self-actuating reactor shutdown system incorporating a thermionic switched electromagnetic latch arrangement which is responsive to reactor neutron flux changes and to reactor coolant temperature changes. The system is self-actuating in that the sensing thermionic device acts directly to release (scram) the control rod (absorber) without reference or signal from the main reactor plant protective and control systems. To be responsive to both temperature and neutron flux effects, two detectors are used, one responsive to reactor coolant temperatures, and the other responsive to reactor neutron flux increase. The detectors are incorporated into a thermionic diode connected electrically with an electromagnetic mechanism which under normal reactor operating conditions holds the the control rod in its ready position (exterior of the reactor core). Upon reaching either a specified temperature or neutron flux, the thermionic diode functions to short-circuit the electromagnetic mechanism causing same to lose its holding power and release the control rod, which drops into the reactor core region under gravitational force.

  2. Switch Switch

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat Sun Mon...

  3. Switch Switch

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    XPP L345 BRESSLER,CHRISTIAN Femtosecond Spin State Changes - Implications for Photocatalysis David Fritz or Marco Cammarata CXI L352 ELMLUND,HANS SINGLE PARTICLE X RAY...

  4. Reducing Actuator Switchings for Motion Control of Autonomous Underwater Vehicles

    E-Print Network [OSTI]

    Smith, Ryan N.

    Reducing Actuator Switchings for Motion Control of Autonomous Underwater Vehicles Monique Chyba and energy minimization for AUVs). A major difficulty is to provide a formal estimation that compares

  5. Multi-gap high impedance plasma opening switch

    DOE Patents [OSTI]

    Mason, R.J.

    1996-10-22T23:59:59.000Z

    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.

  6. Multi-gap high impedance plasma opening switch

    DOE Patents [OSTI]

    Mason, Rodney J. (Los Alamos, NM)

    1996-01-01T23:59:59.000Z

    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.

  7. Modeling Combustion Control for High Power Diesel Mode Switching

    Broader source: Energy.gov (indexed) [DOE]

    Directions in Engine-Efficiency and Emissions Research Conference 2010 Modeling Combustion Control for High Power Diesel Mode Switching Siddhartha Banerjee, Christopher J. Rutland...

  8. Fuel Switching Strategies for the 1990s

    E-Print Network [OSTI]

    Cascone, R.

    , petroleum coke, waste hydrocarbons (such as recovered from lubricants), biomass, and in the near future, methanol and other oxygenates or alcohols. Coal may also conceivably be a long-term sWitching candidate when utilized in a number of advanced open... under mos t conditions, in a manner that generates less NO x than heavier fuels such as coal, coke, and residual oil. Achieving NO x reductions with the latter is often a matter of capital investments and operating costs in either combustion...

  9. GaAs photoconductive semiconductor switch

    DOE Patents [OSTI]

    Loubriel, G.M.; Baca, A.G.; Zutavern, F.J.

    1998-09-08T23:59:59.000Z

    A high gain, optically triggered, photoconductive semiconductor switch (PCSS) implemented in GaAs as a reverse-biased pin structure with a passivation layer above the intrinsic GaAs substrate in the gap between the two electrodes of the device is disclosed. The reverse-biased configuration in combination with the addition of the passivation layer greatly reduces surface current leakage that has been a problem for prior PCSS devices and enables employment of the much less expensive and more reliable DC charging systems instead of the pulsed charging systems that needed to be used with prior PCSS devices. 5 figs.

  10. GaAs photoconductive semiconductor switch

    DOE Patents [OSTI]

    Loubriel, Guillermo M. (Sandia Park, NM); Baca, Albert G. (Albuquerque, NM); Zutavern, Fred J. (Albuquerque, NM)

    1998-01-01T23:59:59.000Z

    A high gain, optically triggered, photoconductive semiconductor switch (PCSS) implemented in GaAs as a reverse-biased pin structure with a passivation layer above the intrinsic GaAs substrate in the gap between the two electrodes of the device. The reverse-biased configuration in combination with the addition of the passivation layer greatly reduces surface current leakage that has been a problem for prior PCSS devices and enables employment of the much less expensive and more reliable DC charging systems instead of the pulsed charging systems that needed to be used with prior PCSS devices.

  11. Elastomeric organic material for switching application

    SciTech Connect (OSTI)

    Shiju, K., E-mail: shijuvenus@gmail.com, E-mail: pravymon@gmail.com, E-mail: ppredeep@gmail.com; Praveen, T., E-mail: shijuvenus@gmail.com, E-mail: pravymon@gmail.com, E-mail: ppredeep@gmail.com; Preedep, P., E-mail: shijuvenus@gmail.com, E-mail: pravymon@gmail.com, E-mail: ppredeep@gmail.com [Laboratory for Molecular Photonics and Electronics (LAMP), Department of Physics, National Institute of Technology, Calicut, Kerala, 673601 (India)

    2014-10-15T23:59:59.000Z

    Organic Electronic devices like OLED, Organic Solar Cells etc are promising as, cost effective alternatives to their inorganic counterparts due to various reasons. However the organic semiconductors currently available are not attractive with respect to their high cost and intricate synthesis protocols. Here we demonstrate that Natural Rubber has the potential to become a cost effective solution to this. Here an attempt has been made to fabricate iodine doped poly isoprene based switching device. In this work Poly methyl methacrylate is used as dielectric layer and Aluminium are employed as electrodes.

  12. Organic solid state optical switches and method for producing organic solid state optical switches

    DOE Patents [OSTI]

    Wasielewski, M.R.; Gaines, G.L.; Niemczyk, M.P.; Johnson, D.G.; Gosztola, D.J.; O`Neil, M.P.

    1993-01-01T23:59:59.000Z

    This invention consists of a light-intensity dependent molecular switch comprised of a compound which shuttles an electron or a plurality of electrons from a plurality of electron donors to an electron acceptor upon being stimulated with light of predetermined wavelengths, and a method for making said compound.

  13. Thickness independent reduced forming voltage in oxygen engineered HfO{sub 2} based resistive switching memories

    SciTech Connect (OSTI)

    Sharath, S. U., E-mail: sharath@oxide.tu-darmstadt.de; Kurian, J.; Komissinskiy, P.; Hildebrandt, E.; Alff, L. [Institute of Materials Science, Technische Universitt Darmstadt, 64287 Darmstadt (Germany); Bertaud, T.; Walczyk, C.; Calka, P. [IHP, Im Technologiepark 25, 15236 Frankfurt Oder (Germany); Schroeder, T. [IHP, Im Technologiepark 25, 15236 Frankfurt Oder (Germany); Brandenburgische Technische Universitt, Konrad-Zuse-Strasse 1, 03046 Cottbus (Germany)

    2014-08-18T23:59:59.000Z

    The conducting filament forming voltage of stoichiometric hafnium oxide based resistive switching layers increases linearly with layer thickness. Using strongly reduced oxygen deficient hafnium oxide thin films grown on polycrystalline TiN/Si(001) substrates, the thickness dependence of the forming voltage is strongly suppressed. Instead, an almost constant forming voltage of about 3?V is observed up to 200?nm layer thickness. This effect suggests that filament formation and switching occurs for all samples in an oxidized HfO{sub 2} surface layer of a few nanometer thickness while the highly oxygen deficient thin film itself merely serves as a oxygen vacancy reservoir.

  14. Design, fabrication and testing of a lateral self-cleaning MEMS switch

    E-Print Network [OSTI]

    Shi, Yong, 1965-

    2004-01-01T23:59:59.000Z

    A lateral contact MEMS switch has been developed to address the need for a long life cycle, low contact resistance RF switch. At the present time, there is no commercial MEMS switch that meets all the requirements. The ...

  15. Resistive switching of a TaO{sub x}/TaON double layer via ionic control of carrier tunneling

    SciTech Connect (OSTI)

    Jeon, Heeyoung; Park, Jingyu; Kim, Hyunjung [Department of Nano-Scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Jang, Woochool; Song, Hyoseok [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Kang, Chunho [Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); FAB Manufacturing Division, SK Hynix Inc., 2091, Gyeongchung-daero, Bubal-eub, Icheon-si, Gyeonggi-do 167-701 (Korea, Republic of); Seo, Hyungtak, E-mail: hseo@ajou.ac.kr [Department of Materials Science and Engineering and Department of Energy Systems Research, Ajou University, Suwon 443-739 (Korea, Republic of); Jeon, Hyeongtag, E-mail: hjeon@hanyang.ac.kr [Department of Nano-Scale Semiconductor Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of); Division of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2014-04-14T23:59:59.000Z

    Resistance random access memory (RRAM) is an attractive candidate for future non-volatile memory due to its superior features. As the oxide thickness is scaled down, the charge transport mechanism is also subject to the transition from hopping to tunneling dominant process, which is critically related to the interfacial electronic band structure. A TaO{sub x}/TaON double layer-based RRAM is fabricated and characterized in this work. Upon TaON insertion at the lower interface, the improved switching behavior is observed. The TaON at the bottom electrode interface blocks oxygen vacancy percolation due to strong N-O bonds and also modifies interfacial band alignment to lower the injected electron energy from bottom electrode due to higher tunneling barrier height than that of TaO{sub x}/Pt. This study suggested that a defect-minimized insertion layer like TaON with a proper interfacial band alignment is pivotal in RRAM for the effective ionic control of carrier tunneling resulting in non-linear I-V behavior with improved properties.

  16. Interactive Visibility Culling in Complex Environments using Occlusion-Switches

    E-Print Network [OSTI]

    North Carolina at Chapel Hill, University of

    Categories and Subject Descriptors: I.3.5 [Com- puter Graphics]: Computational Geometry and Object ModelingInteractive Visibility Culling in Complex Environments using Occlusion-Switches Naga K. Govindaraju culling in complex 3D environments. An occlusion- switch consists of two GPUs (graphics processing units

  17. Valuation of Energy Storage: An Optimal Switching Rene Carmona

    E-Print Network [OSTI]

    Carmona, Rene

    Valuation of Energy Storage: An Optimal Switching Approach Ren´e Carmona Department of Operations://www.pstat.ucsb.edu/faculty/ludkovski We consider the valuation of energy storage facilities within the framework of stochastic control;Carmona and Ludkovski: Optimal Switching for Energy Storage 2 in the commodity financial markets. Storage

  18. Entry, Innovation, and Exit Evidence From LAN Switch Industry

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Entry, Innovation, and Exit Evidence From LAN Switch Industry N° 2007-02 Janvier 2007 Roberto Fontana Lionel Nesta #12;Entry, Innovation, and Exit Evidence From LAN Switch Industry Roberto Fontana of heterogeneous exit, we find that firms with high pre-entry experience and higher technical expertise are more

  19. Bandwidth Efficient All-to-All Broadcast on Switched Clusters

    E-Print Network [OSTI]

    Yuan, Xin

    Bandwidth Efficient All-to-All Broadcast on Switched Clusters Ahmad Faraj Pitch Patarasuk Xin Yuan}@cs.fsu.edu Abstract We develop an all-to-all broadcast scheme that achieves maximum bandwidth efficiency for clusters all- to-all broadcast as efficiently as a single switch connect- ing all machines when the message

  20. DC switching regulated power supply for driving an inductive load

    DOE Patents [OSTI]

    Dyer, G.R.

    1983-11-29T23:59:59.000Z

    A dc switching regulated power supply for driving an inductive load is provided. The regulator basic circuit is a bridge arrangement of diodes and transistors. First and second opposite legs of the bridge are formed by first and second parallel-connected transistor arrays, respectively, while the third and fourth legs of the bridge are formed by appropriately connected first and second parallel connected diode arrays, respectively. A dc power supply is connected to the input of the bridge and the output is connected to the load. A servo controller is provided to control the switching rate of the transistors to maintain a desired current to the load. The regulator may be operated in three stages or modes: (1) for current runup in the load, both first and second transistor switch arrays are turned on and current is supplied to the load through both transistor arrays. (2) When load current reaches the desired level, the first switch is turned off, and load current flywheels through the second switch array and the fourth leg diode array connecting the second switch array in series with the load. Current is maintained by alternating between modes 1 and 2 at a suitable duty cycle and switching rate set by the controller. (3) Rapid current rundown is accomplished by turning both switch arrays off, allowing load current to be dumped back into the source through the third and fourth diode arrays connecting the source in series opposition with the load to recover energy from the inductive load.

  1. DC switching regulated power supply for driving an inductive load

    DOE Patents [OSTI]

    Dyer, George R. (Norris, TN)

    1986-01-01T23:59:59.000Z

    A power supply for driving an inductive load current from a dc power supply hrough a regulator circuit including a bridge arrangement of diodes and switching transistors controlled by a servo controller which regulates switching in response to the load current to maintain a selected load current. First and second opposite legs of the bridge are formed by first and second parallel-connected transistor arrays, respectively, while the third and fourth legs of the bridge are formed by appropriately connected first and second parallel connected diode arrays, respectively. The regulator may be operated in three "stages" or modes: (1) For current runup in the load, both first and second transistor switch arrays are turned "on" and current is supplied to the load through both transistor arrays. (2) When load current reaches the desired level, the first switch is turned "off", and load current "flywheels" through the second switch array and the fourth leg diode array connecting the second switch array in series with the load. Current is maintained by alternating between modes 1 and 2 at a suitable duty cycle and switching rate set by the controller. (3) Rapid current rundown is accomplished by turning both switch arrays "off", allowing load current to be dumped back into the source through the third and fourth diode arrays connecting the source in series opposition with the load to recover energy from the inductive load. The three operating states are controlled automatically by the controller.

  2. Task Assignment in a Server Farm with Switching Delays and

    E-Print Network [OSTI]

    Hyyti, Esa

    Task Assignment in a Server Farm with Switching Delays and General Energy-Aware Cost Structure Esa Servers Customers Basic problem E[T] k parallel queues Tasks arrive at rate (Poisson process) Objective;Switching Delays and Energy Model for Server Farm k parallel servers Size-aware setting Dispatcher Servers

  3. Comparative Study of Switched Reluctance Motors Performances for Two Current

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of machines as high torque ripple, high acoustic noise and vibration limit their industrial applications [1Comparative Study of Switched Reluctance Motors Performances for Two Current Distributions a 3-phase, 6-slot, and 4-pole Mutually Coupled Switched Reluctance Motor (MCSRM 6/4) with new current

  4. Power Control for Crossbar-based Input-Queued Switches

    E-Print Network [OSTI]

    , if f is the maximum digital signal frequency, the power consumption of a CMOS device is proportional number of data simultaneously flowing across the switching fabric. Thermal power dissipation is becoming1 Power Control for Crossbar-based Input-Queued Switches Andrea Bianco, Paolo Giaccone, Guido

  5. On the Power of Nonlinear Mappings in Switching Map Systems

    E-Print Network [OSTI]

    Sato, Yuzuru

    On the Power of Nonlinear Mappings in Switching Map Systems Yuzuru Sato 1 # , Makoto Taiji 2 operations would be allowed. It is also expected that the computational power of switching map systems stronger computational power than classical Turing machines. On the other hand, these dynamical systems

  6. Tunnel MOS Heterostructure Field Effect Transistor for RF Switching Applications

    E-Print Network [OSTI]

    Rezanezhad Gatabi, Iman

    2013-06-06T23:59:59.000Z

    structure called Tunnel MOS Heterostructure FET (TMOSHFET) is introduced which has lower ON-state resistance and faster switching speed compared to conventional AlGaN/GaN HEMTs. In the switch ON process, the channel of this device is charged up by electron...

  7. Multistage-Based Switching Fabrics for Scalable Routers

    E-Print Network [OSTI]

    Tzeng, Nian-Feng

    with distributed packet routing to achieve high scalability and low costs. Our fabrics are based on a multistage patterns are evaluated and discussed as well. Being scalable and of low costs, the proposed switching their arrival LCs toward their destined LCs. Switching fabrics naturally affect overall router perfor- mance

  8. A spin light emitting diode incorporating ability of electrical helicity switching

    SciTech Connect (OSTI)

    Nishizawa, N., E-mail: nishizawa@isl.titech.ac.jp; Nishibayashi, K.; Munekata, H. [Imaging Science and Engineering Laboratory, Tokyo Institute of Technology, 4259-J3-15 Nagatsuta, Midori-ku, Yokohama 226-8503 (Japan)

    2014-03-17T23:59:59.000Z

    Fabrication and optical characteristics of a spin light-emitting-diode (spin-LED) having dual spin-injection electrodes with anti-parallel magnetization configuration are reported. Alternating a current between the two electrodes using a computer-driven current source has led us to the observation of helicity switching of circular polarization at the frequency of 1 kHz. Neither external magnetic fields nor optical delay modulators were used. Sending dc-currents to both electrodes with appropriate ratio has resulted in continuous variation of circular polarization between the two opposite helicity, including the null polarization. These results suggest that the tested spin-LED has the feasibility of a monolithic light source whose circular polarization can be switched or continuously tuned all electrically.

  9. Reconfigurable optical switches with monolithic electrical-to-optical interfaces

    SciTech Connect (OSTI)

    Cheng, J.; Zhou, P. [New Mexico Univ., Albuquerque, NM (United States). Center for High Technology Materials; Zolper, J.C.; Lear, K.L.; Vawter, G.A. [Sandia National Labs., Albuquerque, NM (United States); Leibenguth, R.E.; Adams, A.C. [AT and T Bell Labs., Breinigsville, PA (United States)

    1994-03-01T23:59:59.000Z

    Vertical cavity surface-emitting lasers (VCSELs) can be integrated with heterojunction phototransistors (HPTs) and heterojunction bipolar transistors (HBTs) on the same wafer to form high speed optical and optoelectronic switches, respectively, that can be optically or electrically addressed. This permits the direct communication and transmission of data between distributed electronic processors through an optical switching network. The experimental demonstration of an integrated optoelectronic HBT/VCSEL switch combining a GaAs/AlGaAs heterojunction bipolar transistor (HBT) with a VCSEL is described below, using the same epilayer structure upon which binary HPT/VCSEL optical switches are also built. The monolithic HBT/VCSEL switch has high current gain, low power dissipation, and a high optical to electrical conversion efficiency. Its modulation has been measured and modeled.

  10. Redesign of the H-Bridge Switch Plate of the SNS High Voltage Converter Modulator

    SciTech Connect (OSTI)

    Kemp, M.A.; Burkhart, C.; Nguyen, M.N.; /SLAC; Anderson, D.E.; /Oak Ridge

    2009-05-07T23:59:59.000Z

    The 1-MW High Voltage Converter Modulators [1] have operated in excess of 250,000 hours at the Spallation Neutron Source. Increased demands on the accelerator performance require increased modulator reliability. An effort is underway at SLAC National Accelerator Laboratory to redesign the modulator H-bridge switch plate with the goals of increasing reliability and performance [2]. The major difference between the SLAC design and the existing design is the use of press-pack IGBTs. Compared to other packaging options, these IGBTs have been shown to have increased performance in pulsed-power applications, have increased cooling capability, and do not fragment and disassemble during a fault event. An overview of the SLAC switch plate redesign is presented. Design steps including electrical modeling of the modulator and H-bridge, development of an integrated IGBT clamping mechanism, and fault tests are discussed. Experimental results will be presented comparing electrical performance of the SLAC switch plate to the existing switchplate under normal and fault conditions.

  11. Semiconductor switch geometry with electric field shaping

    DOE Patents [OSTI]

    Booth, Rex (Livermore, CA); Pocha, Michael D. (Livermore, CA)

    1994-01-01T23:59:59.000Z

    An optoelectric switch is disclosed that utilizes a cylindrically shaped and contoured GaAs medium or other optically active semiconductor medium to couple two cylindrically shaped metal conductors with flat and flared termination points each having an ovoid prominence centrally extending there from. Coupling the truncated ovoid prominence of each conductor with the cylindrically shaped optically active semiconductor causes the semiconductor to cylindrically taper to a triple junction circular line at the base of each prominence where the metal conductor conjoins with the semiconductor and a third medium such as epoxy or air. Tapering the semiconductor at the triple junction inhibits carrier formation and injection at the triple junction and thereby enables greater current carrying capacity through and greater sensitivity of the bulk area of the optically active medium.

  12. Semiconductor switch geometry with electric field shaping

    DOE Patents [OSTI]

    Booth, R.; Pocha, M.D.

    1994-08-23T23:59:59.000Z

    An optoelectric switch is disclosed that utilizes a cylindrically shaped and contoured GaAs medium or other optically active semiconductor medium to couple two cylindrically shaped metal conductors with flat and flared termination points each having an ovoid prominence centrally extending there from. Coupling the truncated ovoid prominence of each conductor with the cylindrically shaped optically active semiconductor causes the semiconductor to cylindrically taper to a triple junction circular line at the base of each prominence where the metal conductor conjoins with the semiconductor and a third medium such as epoxy or air. Tapering the semiconductor at the triple junction inhibits carrier formation and injection at the triple junction and thereby enables greater current carrying capacity through and greater sensitivity of the bulk area of the optically active medium. 10 figs.

  13. Permanent-magnet switched-flux machine

    DOE Patents [OSTI]

    Trzynadlowski, Andrzej M.; Qin, Ling

    2010-01-12T23:59:59.000Z

    A permanent-magnet switched-flux (PMSF) device has a ferromagnetic outer stator mounted to a shaft about a central axis extending axially through the PMSF device. Pluralities of top and bottom stator poles are respectively mounted in first and second circles, radially outwardly in first and second transverse planes extending from first and second sections of the central axis adjacent to an inner surface of the ferromagnetic outer stator. A ferromagnetic inner rotor is coupled to the shaft and has i) a rotor core having a core axis co-axial with the central axis; and ii) first and second discs having respective outer edges with first and second pluralities of permanent magnets (PMs) mounted in first and second circles, radially outwardly from the rotor core axis in the first and second transverse planes. The first and second pluralities of PMs each include PMs of alternating polarity.

  14. Eddy-current-damped microelectromechanical switch

    DOE Patents [OSTI]

    Christenson, Todd R. (Albuquerque, NM); Polosky, Marc A. (Tijeras, NM)

    2009-12-15T23:59:59.000Z

    A microelectromechanical (MEM) device is disclosed that includes a shuttle suspended for movement above a substrate. A plurality of permanent magnets in the shuttle of the MEM device interact with a metal plate which forms the substrate or a metal portion thereof to provide an eddy-current damping of the shuttle, thereby making the shuttle responsive to changes in acceleration or velocity of the MEM device. Alternately, the permanent magnets can be located in the substrate, and the metal portion can form the shuttle. An electrical switch closure in the MEM device can occur in response to a predetermined acceleration-time event. The MEM device, which can be fabricated either by micromachining or LIGA, can be used for sensing an acceleration or deceleration event (e.g. in automotive applications such as airbag deployment or seat belt retraction).

  15. Eddy-current-damped microelectromechanical switch

    DOE Patents [OSTI]

    Christenson, Todd R. (Albuquerque, NM); Polosky, Marc A. (Tijeras, NM)

    2007-10-30T23:59:59.000Z

    A microelectromechanical (MEM) device is disclosed that includes a shuttle suspended for movement above a substrate. A plurality of permanent magnets in the shuttle of the MEM device interact with a metal plate which forms the substrate or a metal portion thereof to provide an eddy-current damping of the shuttle, thereby making the shuttle responsive to changes in acceleration or velocity of the MEM device. Alternately, the permanent magnets can be located in the substrate, and the metal portion can form the shuttle. An electrical switch closure in the MEM device can occur in response to a predetermined acceleration-time event. The MEM device, which can be fabricated either by micromachining or LIGA, can be used for sensing an acceleration or deceleration event (e.g. in automotive applications such as airbag deployment or seat belt retraction).

  16. High voltage photo switch package module

    DOE Patents [OSTI]

    Sullivan, James S; Sanders, David M; Hawkins, Steven A; Sampayan, Stephen E

    2014-02-18T23:59:59.000Z

    A photo-conductive switch package module having a photo-conductive substrate or wafer with opposing electrode-interface surfaces, and at least one light-input surface. First metallic layers are formed on the electrode-interface surfaces, and one or more optical waveguides having input and output ends are bonded to the substrate so that the output end of each waveguide is bonded to a corresponding one of the light-input surfaces of the photo-conductive substrate. This forms a waveguide-substrate interface for coupling light into the photo-conductive wafer. A dielectric material such as epoxy is then used to encapsulate the photo-conductive substrate and optical waveguide so that only the metallic layers and the input end of the optical waveguide are exposed. Second metallic layers are then formed on the first metallic layers so that the waveguide-substrate interface is positioned under the second metallic layers.

  17. A New Optical Switching Fabric Architecture Incorporating Rapidly Switching All-Optical Variable Delay Buffers

    E-Print Network [OSTI]

    Kolner, Brian H.

    - optical random access memory. While the theoretical and experimental work for the optical-label switching of the output delay buffer. Electronic On-Off Logic 2^(N-1)T 2^(N-2)T T Electronic On-Off Logic 2^(N-1)T 2^(N-2)T T ? i Electronic On-Off Logic 2^(N-1)T 2^(N-2)T T Electronic On-Off Logic 2^(N-1)T 2^(N-2)T T ? i

  18. Dynamical switching characteristics of a bistable injection laser

    SciTech Connect (OSTI)

    Lau, K.Y.; Harder, C.; Yariv, A.

    1982-02-01T23:59:59.000Z

    The switching characteristics of a bistable injection laser with very large hysteresis is examined. Switch-on delays are shown to exhibit a ''critical'' part and a ''noncritical'' part, both of which can be reduced by increasing the overdrive current. It is possible to obtain fairly fast switching time (<20 ns) with a strong overdrive. Nominal delays of 100--200 ns result under moderate overdrives. These long time scales are due to long carrier lifetimes in the carrier-depleted absorption section, a property intrinsic to these bistable injection lasers.

  19. Spintronic switches for ultra low energy global interconnects

    SciTech Connect (OSTI)

    Sharad, Mrigank, E-mail: msharad@purdue.edu; Roy, Kaushik [School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)

    2014-05-07T23:59:59.000Z

    We present ultra-low energy interconnect design using nano-scale spin-torque (ST) switches for global data-links. Emerging spin-torque phenomena can lead to ultra-low-voltage, high-speed current-mode magnetic-switches. ST-switches can simultaneously provide large trans-impedance gain by employing magnetic tunnel junctions, to convert current-mode signals into large-swing voltage levels. Such device-characteristics can be used in the design of energy-efficient current-mode global interconnects.

  20. Higher Resolution VLBI Imaging with Fast Frequency Switching

    E-Print Network [OSTI]

    E. Middelberg; A. L. Roy; R. C. Walker; H. Falcke; T. P. Krichbaum

    2002-07-03T23:59:59.000Z

    Millimetre-VLBI is an important tool in AGN astrophysics, but it is limited by short atmospheric coherence times and poor receiver and antenna performance. We demonstrate a new kind of phase referencing for the VLBA, enabling us to increase the sensitivity in mm-VLBI by an order of magnitude. If a source is observed in short cycles between the target frequency, nu_t, and a reference frequency, nu_ref, the nu_t data can be calibrated using scaled-up phase solutions from self-calibration at nu_ref. We have demonstrated the phase transfer on 3C 279, where we were able to make an 86 GHz image with 90 % coherence compared to self-calibration at nu_t. We have detected M81, our science target in this project, at 86 GHz using the same technique. We describe scheduling strategy and data reduction. The main impacts of fast frequency switching are the ability to image some of the nearest, but relatively weak AGN cores with unprecedented high angular resolution and to phase-reference the nu_t data to the nu_ref core position, enabling the detection of possible core shifts in jets due to optical depth effects. This ability will yield important constraints on jet properties and might be able to discriminate between the two competing emission models of Blandford-Konigl jets and spherical advection-dominated accretion flows (ADAFs) in low-luminosity AGNs.

  1. On the Combined Input-Crosspoint Buffered Switch with Round-Robin Arbitration

    E-Print Network [OSTI]

    Rojas-Cessa, Roberto

    through. Therefore, the search for switch/router architectures with high performance and large capacity) Segmentation of incoming variable-size packets at the ingress side of a switch to perform internal switching, the performance of packet switches are con- strained by memory speed and the efficiency of the arbitration scheme

  2. Partial Observers

    E-Print Network [OSTI]

    Thomas Marlow

    2006-10-20T23:59:59.000Z

    We attempt to dissolve the measurement problem using an anthropic principle which allows us to invoke rational observers. We argue that the key feature of such observers is that they are rational (we need not care whether they are `classical' or `macroscopic' for example) and thus, since quantum theory can be expressed as a rational theory of probabilistic inference, the measurement problem is not a problem.

  3. Multi-line triggering and interdigitated electrode structure for photoconductive semiconductor switches

    DOE Patents [OSTI]

    Mar, Alan (Albuquerque, NM); Zutavern, Fred J. (Albuquerque, NM); Loubriel, Guillermo (Albuquerque, NM)

    2007-02-06T23:59:59.000Z

    An improved photoconductive semiconductor switch comprises multiple-line optical triggering of multiple, high-current parallel filaments between the switch electrodes. The switch can also have a multi-gap, interdigitated electrode for the generation of additional parallel filaments. Multi-line triggering can increase the switch lifetime at high currents by increasing the number of current filaments and reducing the current density at the contact electrodes in a controlled manner. Furthermore, the improved switch can mitigate the degradation of switching conditions with increased number of firings of the switch.

  4. Throughput-cost analysis of optical flow switching

    E-Print Network [OSTI]

    Chan, Vincent W. S.

    In this paper, we employ a cost model embodying major sources of capital expenditure (CapEx) to compare the throughput-cost tradeoff offered by optical flow switching to that of more traditional optical network architectures.

  5. Reducing Actuator Switchings for Motion Control of Autonomous Underwater Vehicles

    E-Print Network [OSTI]

    Smith, Ryan N.

    Reducing Actuator Switchings for Motion Control of Autonomous Underwater Vehicles Monique Chyba, such as time, energy, payload or some combination of these. Indeed, the major issue is that due to the vehicles

  6. Using Multiprotocol Label Switching in Virtual Private Networks

    E-Print Network [OSTI]

    Doddapaneni, Krishnamohan

    2001-01-01T23:59:59.000Z

    This thesis presents the design of Multiprotocol Label Switching Virtual Private Networks(MPLS VPN). MPLS VPNs are true peer models, which perform traffic separation at Layer 3, through the implementation of separate IP VPN forwarding tables. MPLS...

  7. ab switched current: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    interfaces with the ac grid using a pulsewidth-modulation (PWM) inverter. In 3, a variable-speed wind turbine for a Switched Reluctance Wind Generator, Based on Current...

  8. atrial switch operation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    interfaces with the ac grid using a pulsewidth-modulation (PWM) inverter. In 3, a variable-speed wind turbine for a Switched Reluctance Wind Generator, Based on Current...

  9. arterial switch operation: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    interfaces with the ac grid using a pulsewidth-modulation (PWM) inverter. In 3, a variable-speed wind turbine for a Switched Reluctance Wind Generator, Based on Current...

  10. Data Parallel SwitchLevel Simulation \\Lambda Randal E. Bryant

    E-Print Network [OSTI]

    Bryant, Randal E.

    Data Parallel SwitchLevel Simulation \\Lambda Randal E. Bryant Computer Science Department Carnegie the bitlevel paral lelism inherent in conventional machine operations. Bryant---Data Parallel Simulation

  11. Oxygen enhanced switching to combustion of lower rank fuels ...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    enhanced switching to combustion of lower rank fuels Re-direct Destination: A furnace that combusts fuel, such as coal, of a given minimum energy content to obtain a stated minimum...

  12. Bayesian Nonparametric Methods for Learning Markov Switching Processes

    E-Print Network [OSTI]

    Fox, Emily Beth

    In this article, we explored a Bayesian nonparametric approach to learning Markov switching processes. This framework requires one to make fewer assumptions about the underlying dynamics, and thereby allows the data to ...

  13. Development and application of an advanced switched reluctance generator drive

    E-Print Network [OSTI]

    Asadi, Peyman

    2009-05-15T23:59:59.000Z

    This dissertation contains the results of research conducted on the design and control characterization of a Switched Reluctance Generator (SRG) for maximum output power. The SRG is an attractive solution to the increasing worldwide demand...

  14. Coordinated Variable Structure Switching Attacks for Smart Grid

    E-Print Network [OSTI]

    Liu, Shan

    2013-02-11T23:59:59.000Z

    or more relays and circuit breakers of a power system to disrupt operation. Existence of this switching vulnerability is dependent on the local structure of the power grid. Variable structure systems theory is employed to effectively model the cyber...

  15. All graphene electromechanical switch fabricated by chemical vapor deposition

    E-Print Network [OSTI]

    Milaninia, Kaveh M.

    We demonstrate an electromechanical switch comprising two polycrystalline graphene films; each deposited using ambient pressure chemical vapor deposition. The top film is pulled into electrical contact with the bottom film ...

  16. AlGaN/GaN-based power semiconductor switches

    E-Print Network [OSTI]

    Lu, Bin, Ph. D. Massachusetts Institute of Technology

    2013-01-01T23:59:59.000Z

    AlGaN/GaN-based high-electron-mobility transistors (HEMTs) have great potential for their use as high efficiency and high speed power semiconductor switches, thanks to their high breakdown electric field, mobility and ...

  17. Scheduling in switched queueing networks with heavy-tailed trac

    E-Print Network [OSTI]

    Markakis, Mihalis G

    2013-01-01T23:59:59.000Z

    We study scheduling problems arising in switched queueing networks, a class of stochastic systems that are often used to model data communication networks, such as uplinks and downlinks of cellular networks, networks of ...

  18. Integrated optical switching using titanium nitride micro electromechanical systems

    E-Print Network [OSTI]

    Takahashi, Satoshi, Ph. D. Massachusetts Institute of Technology

    2006-01-01T23:59:59.000Z

    This thesis reports an integrated optical wavelength specific switching device for applications in optical integrated circuits (OICs) based on micro electromechanical systems (MEMS). The device consists of a ring resonator ...

  19. Plasmon-induced photonic switching in a metamaterial

    E-Print Network [OSTI]

    H. Xu; B. S. Ham

    2009-05-22T23:59:59.000Z

    Using light-induced localized surface plasmon interactions in a metamaterial, we present a plasmonic control of light absorption for photonic switching. We discuss that the present surface plasmon-induced photonic switching is comparable with coherence swapping in a tripod optical system based on electromagnetically induced transparency. This outcome opens a door to active controls of the surface plasmons in a metamaterial for potential applications of nano photonics.

  20. All-optical switching in optically induced nonlinear waveguide couplers

    SciTech Connect (OSTI)

    Diebel, Falko, E-mail: falko.diebel@uni-muenster.de; Boguslawski, Martin; Rose, Patrick; Denz, Cornelia [Institut fr Angewandte Physik and Center for Nonlinear Science (CeNoS), Westflische Wilhelms-Universitt Mnster, 48149 Mnster (Germany); Leykam, Daniel; Desyatnikov, Anton S. [Nonlinear Physics Centre, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia)

    2014-06-30T23:59:59.000Z

    We experimentally demonstrate all-optical vortex switching in nonlinear coupled waveguide arrays optically induced in photorefractive media. Our technique is based on multiplexing of nondiffracting Bessel beams to induce various types of waveguide configurations. Using double- and quadruple-well potentials, we demonstrate precise control over the coupling strength between waveguides, the linear and nonlinear dynamics and symmetry-breaking bifurcations of guided light, and a power-controlled optical vortex switch.

  1. RF-MEMS Switched Varactors for Medium Power Applications

    E-Print Network [OSTI]

    Maury, F; Crunteanu, A; Conseil, F; Blondy, P

    2008-01-01T23:59:59.000Z

    In RF (Radio Frequency) domain, one of the limitations of using MEMS (Micro Electromechanical Systems) switching devices for medium power applications is RF power. Failure phenomena appear even for 500 mW. A design of MEMS switched capacitors with an enhanced topology is presented in this paper to prevent it. This kind of device and its promising performances will serve to fabricate a MEMS based phase shifter able to work under several watts.

  2. Design of switched-resistor monolithic filters using NMOS technology

    E-Print Network [OSTI]

    Ngo, Dinh Tai

    1981-01-01T23:59:59.000Z

    DESIGN OF SWITCHED-RESISTOR MONOLITHIC FILTERS USING NMOS TECHNOLOGY A Thesis by DINH TAI NGO Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December... 1981 Major Subject: Electrical Engineering DESIGN OF SWITCHED-RESISTOR MONOLITHIC FILTERS USING NMOS TECHNOLOGY A Thesis by DINH TAI NGO Approved as to style and content by J+ (' ll ( (C airman of Comm'it tee) (Member) (Member) ( d of De...

  3. Electronically commutated serial-parallel switching for motor windings

    DOE Patents [OSTI]

    Hsu, John S. (Oak Ridge, TN)

    2012-03-27T23:59:59.000Z

    A method and a circuit for controlling an ac machine comprises controlling a full bridge network of commutation switches which are connected between a multiphase voltage source and the phase windings to switch the phase windings between a parallel connection and a series connection while providing commutation discharge paths for electrical current resulting from inductance in the phase windings. This provides extra torque for starting a vehicle from lower battery current.

  4. Efficient Switches for Solar Power Conversion: Four Quadrant GaN Switch Enabled Three Phase Grid-Tied Microinverters

    SciTech Connect (OSTI)

    None

    2012-02-13T23:59:59.000Z

    Solar ADEPT Project: Transphorm is developing power switches for new types of inverters that improve the efficiency and reliability of converting energy from solar panels into useable electricity for the grid. Transistors act as fast switches and control the electrical energy that flows in an electrical circuit. Turning a transistor off opens the circuit and stops the flow of electrical current; turning it on closes the circuit and allows electrical current to flow. In this way a transistor can be used to convert DC from a solar panel into AC for use in a home. Transphorms transistors will enable a single semiconductor device to switch electrical currents at high-voltage in both directionsmaking the inverter more compact and reliable. Transphorm is using Gallium Nitride (GaN) as a semiconductor material in its transistors instead of silicon, which is used in most conventional transistors, because GaN transistors have lower losses at higher voltages and switching frequencies.

  5. Breakthrough Technologies In Vivo Observation of Cavitation and Embolism Repair

    E-Print Network [OSTI]

    Holbrook, N. Michele

    Breakthrough Technologies In Vivo Observation of Cavitation and Embolism Repair Using Magnetic that approximately 10 vessels had cavitated during this time. Leaf water potentials decreased from 1.25 to 2.1 MPa cavitation. Refilling of xylem vessels occurred as soon as the lights were switched off, with the majority

  6. Ferroelectric opening switches for large-scale pulsed power drivers.

    SciTech Connect (OSTI)

    Brennecka, Geoffrey L.; Rudys, Joseph Matthew; Reed, Kim Warren; Pena, Gary Edward; Tuttle, Bruce Andrew; Glover, Steven Frank

    2009-11-01T23:59:59.000Z

    Fast electrical energy storage or Voltage-Driven Technology (VDT) has dominated fast, high-voltage pulsed power systems for the past six decades. Fast magnetic energy storage or Current-Driven Technology (CDT) is characterized by 10,000 X higher energy density than VDT and has a great number of other substantial advantages, but it has all but been neglected for all of these decades. The uniform explanation for neglect of CDT technology is invariably that the industry has never been able to make an effective opening switch, which is essential for the use of CDT. Most approaches to opening switches have involved plasma of one sort or another. On a large scale, gaseous plasmas have been used as a conductor to bridge the switch electrodes that provides an opening function when the current wave front propagates through to the output end of the plasma and fully magnetizes the plasma - this is called a Plasma Opening Switch (POS). Opening can be triggered in a POS using a magnetic field to push the plasma out of the A-K gap - this is called a Magnetically Controlled Plasma Opening Switch (MCPOS). On a small scale, depletion of electron plasmas in semiconductor devices is used to affect opening switch behavior, but these devices are relatively low voltage and low current compared to the hundreds of kilo-volts and tens of kilo-amperes of interest to pulsed power. This work is an investigation into an entirely new approach to opening switch technology that utilizes new materials in new ways. The new materials are Ferroelectrics and using them as an opening switch is a stark contrast to their traditional applications in optics and transducer applications. Emphasis is on use of high performance ferroelectrics with the objective of developing an opening switch that would be suitable for large scale pulsed power applications. Over the course of exploring this new ground, we have discovered new behaviors and properties of these materials that were here to fore unknown. Some of these unexpected discoveries have lead to new research directions to address challenges.

  7. Flocking of Multi-agent Dynamical Systems Based on Pseudo-leader Mechanism

    E-Print Network [OSTI]

    Jin Zhou; Wenwu Yu; Xiaoqun Wu; Michael Small; Jun-an Lu

    2009-05-07T23:59:59.000Z

    Flocking behavior of multiple agents can be widely observed in nature such as schooling fish and flocking birds. Recent literature has proposed the possibility that flocking is possible even only a small fraction of agents are informed of the desired position and velocity. However, it is still a challenging problem to determine which agents should be informed or have the ability to detect the desired information. This paper aims to address this problem. By combining the ideas of virtual force and pseudo-leader mechanism, where a pseudo-leader represents an agent who can detect the desired information, we propose a scheme for choosing pseudo-leaders in a multi-agent group. The presented scheme can be applied to a multi-agent group even with an unconnected or switching neighbor graph. Experiments are given to show that the methods presented in this paper are of high accuracy and perform well.

  8. & Mechanical Engineering

    E-Print Network [OSTI]

    Zhou, Chongwu

    , robotics, and the development of new tools for integrated approaches to concurrent engineeringAME Aerospace & Mechanical Engineering #12;Aerospace and Mechanical Engineers design complex Engineering (AME) students conduct basic and applied research within and across the usual disciplinary

  9. Observation of angle-modulated switch between enhancement and suppression of nonlinear

    E-Print Network [OSTI]

    Wu, Shin-Tson

    interaction of four-wave mixing image," Opt. Express 19(14), 1367513685 (2011). 2. N. Li, Z. Zhao, H. Chen, P-Banacloche, "Measurement of dispersive properties of electromagnetically induced transparency in rubidium atoms," Phys. Rev. Li, L. M. Narducci, A. M. Lyyra, and F. C. Spano, "Autler-Townes splitting in molecular lithium

  10. Nano-optical observation of cascade switching in a parallel superconducting nanowire single photon detector

    SciTech Connect (OSTI)

    Heath, Robert M., E-mail: r.heath.1@research.gla.ac.uk; Tanner, Michael G.; Casaburi, Alessandro; Hadfield, Robert H. [School of Engineering, University of Glasgow, Glasgow G12 8LT, Scotland (United Kingdom); Webster, Mark G. [Department of Statistics, University of Leeds, Leeds LS2 9JT (United Kingdom); San Emeterio Alvarez, Lara; Jiang, Weitao; Barber, Zoe H. [Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB3 0FS (United Kingdom); Warburton, Richard J. [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland)

    2014-02-10T23:59:59.000Z

    The device physics of parallel-wire superconducting nanowire single photon detectors is based on a cascade process. Using nano-optical techniques and a parallel wire device with spatially separate pixels, we explicitly demonstrate the single- and multi-photon triggering regimes. We develop a model for describing efficiency of a detector operating in the arm-trigger regime. We investigate the timing response of the detector when illuminating a single pixel and two pixels. We see a change in the active area of the detector between the two regimes and find the two-pixel trigger regime to have a faster timing response than the one-pixel regime.

  11. High peak power test of S-band waveguide switches

    SciTech Connect (OSTI)

    Nassiri, A.; Grelick, A.; Kustom, R.L.; White, M.

    1997-08-01T23:59:59.000Z

    The injector and source of particles for the Advanced Photon Source (APS) is a 2856-MHz S-band electron-positron linear accelerator (linac) which produces electrons with energies up to 650 MeV or positrons with energies up to 450 MeV. To improve the linac rf system availability, an additional modulator-klystron subsystem is being constructed to provide a switchable hot spare unit for each of the five existing S-band transmitters. The switching of the transmitters will require the use of SF6-pressurized waveguide switches at a peak operating power of 35 MW. A test stand was set up at the Stanford Linear Accelerator Center (SLAC) Klystron-Microwave laboratory to conduct tests characterizing the power handling capability of these waveguide switches. Test results are presented.

  12. Utilizing zero-sequence switchings for reversible converters

    DOE Patents [OSTI]

    Hsu, John S.; Su, Gui-Jia; Adams, Donald J.; Nagashima, James M.; Stancu, Constantin; Carlson, Douglas S.; Smith, Gregory S.

    2004-12-14T23:59:59.000Z

    A method for providing additional dc inputs or outputs (49, 59) from a dc-to-ac inverter (10) for controlling motor loads (60) comprises deriving zero-sequence components (V.sub.ao, V.sub.bo, and V.sub.co) from the inverter (10) through additional circuit branches with power switching devices (23, 44, 46), transforming the voltage between a high voltage and a low voltage using a transformer or motor (42, 50), converting the low voltage between ac and dc using a rectifier (41, 51) or an H-bridge (61), and providing at least one low voltage dc input or output (49, 59). The transformation of the ac voltage may be either single phase or three phase. Where less than a 100% duty cycle is acceptable, a two-phase modulation of the switching signals controlling the inverter (10) reduces switching losses in the inverter (10). A plurality of circuits for carrying out the invention are also disclosed.

  13. Fiber-optical switch controlled by a single atom

    E-Print Network [OSTI]

    Danny O'Shea; Christian Junge; Jrgen Volz; Arno Rauschenbeutel

    2013-09-12T23:59:59.000Z

    We demonstrate highly efficient switching of optical signals between two optical fibers controlled by a single atom. The key element of our experiment is a whispering-gallery mode bottle microresonator, which is coupled to a single atom and interfaced by two tapered fiber couplers. Even in the presence of the coupling fibers, the atom--resonator system reaches the strong coupling regime of cavity quantum electrodynamics (CQED), leading to a vacuum Rabi splitting in the excitation spectrum. We systematically investigate the switching efficiency of our system, i.e., the probability that the CQED fiber-optical switch redirects the light into the desired output. We obtain a large redirection efficiency reaching a raw fidelity of more than 60% without post-selection.

  14. Carrier Density Modulation in Ge Heterostructure by Ferroelectric Switching

    SciTech Connect (OSTI)

    Ponath, Patrick [University of Texas at Austin; Fredrickson, Kurt [University of Texas at Austin; Posadas, Agham B. [University of Texas at Austin; Ren, Yuan [University of Texas at Austin; Vasudevan, Rama K [ORNL; Okatan, Mahmut Baris [ORNL; Jesse, Stephen [ORNL; Aoki, Toshihiro [Arizona State University; McCartney, Martha [Arizona State University; Smith, David J [Arizona State University; Kalinin, Sergei V [ORNL; Lai, Keji [University of Texas at Austin; Demkov, Alexander A. [University of Texas at Austin

    2015-01-01T23:59:59.000Z

    The development of nonvolatile logic through direct coupling of spontaneous ferroelectric polarization with semiconductor charge carriers is nontrivial, with many issues, including epitaxial ferroelectric growth, demonstration of ferroelectric switching, and measurable semiconductor modulation. Here we report a true ferroelectric field effect carrier density modulation in an underlying Ge(001) substrate by switching of the ferroelectric polarization in the epitaxial c-axis-oriented BaTiO3 (BTO) grown by molecular beam epitaxy (MBE) on Ge. Using density functional theory, we demonstrate that switching of BTO polarization results in a large electric potential change in Ge. Aberration-corrected electron microscopy confirms the interface sharpness, and BTO tetragonality. Electron-energy-loss spectroscopy (EELS) indicates the absence of any low permittivity interlayer at the interface with Ge. Using piezoelectric force microscopy (PFM), we confirm the presence of fully switchable, stable ferroelectric polarization in BTO that appears to be single domain. Using microwave impedance microscopy (MIM), we clearly demonstrate a ferroelectric field effect.

  15. High voltage switch triggered by a laser-photocathode subsystem

    DOE Patents [OSTI]

    Chen, Ping; Lundquist, Martin L.; Yu, David U. L.

    2013-01-08T23:59:59.000Z

    A spark gap switch for controlling the output of a high voltage pulse from a high voltage source, for example, a capacitor bank or a pulse forming network, to an external load such as a high gradient electron gun, laser, pulsed power accelerator or wide band radar. The combination of a UV laser and a high vacuum quartz cell, in which a photocathode and an anode are installed, is utilized as triggering devices to switch the spark gap from a non-conducting state to a conducting state with low delay and low jitter.

  16. Ultrafast thermally induced magnetic switching in synthetic ferrimagnets

    SciTech Connect (OSTI)

    Evans, Richard F. L., E-mail: richard.evans@york.ac.uk; Ostler, Thomas A.; Chantrell, Roy W. [Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Radu, Ilie [Institut fr Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin fr Materialien und Energie GmbH, Albert-Einstein-Strae 15, 12489 Berlin (Germany); Rasing, Theo [Radboud University, Institute for Molecules and Materials, Heyendaalsewg 135, 6525 AJ Nijmegen (Netherlands)

    2014-02-24T23:59:59.000Z

    Synthetic ferrimagnets are composite magnetic structures formed from two or more anti-ferromagnetically coupled magnetic sublattices with different magnetic moments. Here, we report on atomistic spin simulations of the laser-induced magnetization dynamics on such synthetic ferrimagnets and demonstrate that the application of ultrashort laser pulses leads to sub-picosecond magnetization dynamics and all-optical switching in a similar manner as in ferrimagnetic alloys. Moreover, we present the essential material properties for successful laser-induced switching, demonstrating the feasibility of using a synthetic ferrimagnet as a high density magnetic storage element without the need of a write field.

  17. The design and characterization of switched-resistor filters

    E-Print Network [OSTI]

    Bass, James Traugott

    1983-01-01T23:59:59.000Z

    THE DESIGN AND CHARACTERIZATION OF SWITCHED-RESISTOR FILTERS A Thesis by JAMES TRAUGOTT BASS Submitted to t'ne Graduate College of Texas ARM University in partial fulf'llment of the requirement. for the degree of MASTER OF SCIENCE August... 1983 Major Subjec : Electrical Engineering THE DESIGN AND CHARACTERIZATION OF SWITCHED-RESISTOR FILTERS A THESIS BY JAMES TRAUGOTT BASS Approved as to style and content by: an a I . caper (Chairman of Committee) Nor. an C. GriswoI, d (Member...

  18. High-Power Microwave Switch Employing Electron Beam Triggering

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2012-09-19T23:59:59.000Z

    A high-power active microwave pulse compressor is described that modulates the quality factor Q of the energy storage cavity by a new means involving mode conversion controlled by a triggered electron-beam discharge through a switch cavity. The electron beam is emitted from a diamond-coated molybdenum cathode. This report describes the principle of operation, the design of the switch, the configuration used for the test, and the experimental results. The pulse compressor produced output pulses with 140 - ??165 MW peak power, power gain of 16 - 20, and pulse duration of 16 - 20 ns at a frequency of 11.43 GHz.

  19. The design and characterization of switched-resistor filters

    E-Print Network [OSTI]

    Bass, James Traugott

    1983-01-01T23:59:59.000Z

    THE DESIGN AND CHARACTERIZATION OF SWITCHED-RESISTOR FILTERS A Thesis by JAMES TRAUGOTT BASS Submitted to t'ne Graduate College of Texas ARM University in partial fulf'llment of the requirement. for the degree of MASTER OF SCIENCE August... 1983 Major Subjec : Electrical Engineering THE DESIGN AND CHARACTERIZATION OF SWITCHED-RESISTOR FILTERS A THESIS BY JAMES TRAUGOTT BASS Approved as to style and content by: an a I . caper (Chairman of Committee) Nor. an C. GriswoI, d (Member...

  20. Standard 1D solar atmosphere as initial condition for MHD simulations and switch-on effects

    E-Print Network [OSTI]

    Bourdin, Philippe-A

    2015-01-01T23:59:59.000Z

    Many applications in Solar physics need a 1D atmospheric model as initial condition or as reference for inversions of observational data. The VAL atmospheric models are based on observations and are widely used since decades. Complementary to that, the FAL models implement radiative hydrodynamics and showed the shortcomings of the VAL models since almost equally long time. In this work, we present a new 1D layered atmosphere that spans not only from the photosphere to the transition region, but from the solar interior up to far in the corona. We also discuss typical mistakes that are done when switching on simulations based on such an initial condition and show how the initial condition can be equilibrated so that a simulation can start smoothly. The 1D atmosphere we present here served well as initial condition for HD and MHD simulations and should also be considered as reference data for solving inverse problems.

  1. Semiconductor-based all-optical switching for optical time-division multiplexed networks

    E-Print Network [OSTI]

    Robinson, Bryan S. (Bryan Shawn), 1975-

    2003-01-01T23:59:59.000Z

    All-optical switching will likely be required for future optical networks operating at data rates which exceed electronic processing speeds. Switches utilizing nonlinearities in semiconductor optical amplifiers (SOA) are ...

  2. Top-down proteomics reveals a unique protein S-thiolation switch...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    protein S-thiolation switch in Salmonella Typimurium in response to infection-like Top-down proteomics reveals a unique protein S-thiolation switch in Salmonella Typimurium...

  3. A Molecular Switch Based on Current-Driven Rotation of an Encapsulated...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Switch Based on Current-Driven Rotation of an Encapsulated Cluster within a Fullerene Cage. A Molecular Switch Based on Current-Driven Rotation of an Encapsulated Cluster within a...

  4. A Multi-State Single-Molecule Switch Actuated by Rotation of...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Multi-State Single-Molecule Switch Actuated by Rotation of an Encapsulated Cluster within a Fullerene Cage. A Multi-State Single-Molecule Switch Actuated by Rotation of an...

  5. Utility External Disconnect Switch: Practical, Legal, and Technical Reasons to Eliminate the Requirement

    Broader source: Energy.gov [DOE]

    This report documents the safe operation of PV systems without a utility external disconnect switch in several large jurisdictions. It includes recommendations for regulators contemplating utility external disconnect switch requirements.

  6. A scalable silicon photonic chip-scale optical switch for high performance computing systems

    E-Print Network [OSTI]

    Yoo, S. J. Ben

    A scalable silicon photonic chip-scale optical switch for high performance computing systems-scale optical switch for scalable interconnect network in high performance computing systems. The proposed

  7. Design of Single-Switch Inverters for Variable Resistance/Load Modulation Operation

    E-Print Network [OSTI]

    Roslaniec, Lukasz

    Single-Switch inverters such as the conventional Class-E inverter are often highly load sensitive, and maintain zero-voltage switching over only a narrow range of load resistances. This paper introduces a design methodology ...

  8. In-situ weak-beam and polarization control of multidimensional laser sidebands for ultrafast optical switching

    SciTech Connect (OSTI)

    Liu, Weimin; Wang, Liang; Fang, Chong, E-mail: Chong.Fang@oregonstate.edu [Department of Chemistry, Oregon State University, Corvallis, Oregon 97331 (United States)

    2014-03-17T23:59:59.000Z

    All-optical switching has myriad applications in optoelectronics, optical communications, and quantum information technology. To achieve ultrafast optical switching in a compact yet versatile setup, we demonstrate distinct sets of two-dimensional (2D) broadband up-converted multicolor arrays (BUMAs) in a thin type-I ?-barium-borate crystal with two noncollinear near-IR femtosecond pulses at various phase-matching conditions. The unique interaction mechanism is revealed as quadratic spatial solitons (QSSs)-coupled cascaded four-wave mixing (CFWM), corroborated by numerical calculations of the governing phase-matching conditions. Broad and continuous spectral-spatial tunability of the 2D BUMAs are achieved by varying the time delay between the two incident pulses that undergo CFWM interaction, rooted in the chirped nature of the weak white light and the QSSs generation of the intense fundamental beam. The control of 2D BUMAs is accomplished via seeding a weak second-harmonic pulse in situ to suppress the 2D arrays with polarization dependence on the femtosecond timescale that matches the control pulse duration of ?35 fs. A potential application is proposed on femtosecond all-optical switching in an integrated wavelength-time division multiplexing device.

  9. Why and how should innovative industries with high consumer switching costs be re-regulated?

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    Why and how should innovative industries with high consumer switching costs be re-regulated? N-00973051,version1-3Apr2014 #12;Why and how should innovative industries with high consumer switching costs be re-regulated? Jackie Krafft1 and Evens Salies2 Abstract The existence of costs to consumers to switch

  10. Issues in the design of switched linear control systems: A benchmark study

    E-Print Network [OSTI]

    Duffy, Ken

    Issues in the design of switched linear control systems: A benchmark study Douglas Leith, Robert a tutorial overview of some of the issues that arise in the design of switched linear control systems, and issues concerning the realisation of switched linear controllers (and the associated transient response

  11. A Linear Programming Approach to Time Optimal Control of Integrator Switched Systems with State Constraints

    E-Print Network [OSTI]

    Antsaklis, Panos

    A Linear Programming Approach to Time Optimal Control of Integrator Switched Systems with State, USA Abstract-- In this paper, time optimal control problems of a class of integrator switched systems Recently, optimal control problems of switched and hybrid systems have attracted many researchers from

  12. A Switching Kalman Filter Model for the Motor Cortical Coding of Hand Motion

    E-Print Network [OSTI]

    Bienenstock, Elie

    A Switching Kalman Filter Model for the Motor Cortical Coding of Hand Motion Wei Wu Michael J present a Switching Kalman Filter Model (SKFM) for the real-time inference of hand kinematics from a separate test set is achieved using the Switching Kalman Filter (SKF) algorithm. Quantitative results show

  13. Switching Kalman Filter-Based Approach for Tracking and Event Detection at Traffic Intersections

    E-Print Network [OSTI]

    He, Sheng

    Switching Kalman Filter-Based Approach for Tracking and Event Detection at Traffic Intersections, and (ii) a simple event detection system using the results of a switching Kalman filter in combination outdoor traffic scenes. Keywords Event detection, switching Kalman filter, multi- ple cue-based tracking

  14. Polymer Based Thermo-optic Switch for Optical True Time Delay

    E-Print Network [OSTI]

    Chen, Ray

    Polymer Based Thermo-optic Switch for Optical True Time Delay Xiaolong Wanga , Brie Howleya Warfare Center, Newport, RI 02841 Abstract: A thermo-optic switch using total internal reflection interference. One practical way to implement continuous TTD is to integrate polymer based thermo-optic switches

  15. Polymer Waveguides and Thermo-Optic Switches for an Optical True Time Delay Phased Array Antenna

    E-Print Network [OSTI]

    Chen, Ray

    Polymer Waveguides and Thermo-Optic Switches for an Optical True Time Delay Phased Array Antenna device size. 2x2 thermo-optic TIR switches were fabricated with insertion losses of 2.8 dB. A 4-bit TTD loss of 23.88 dB. Keywords: Optical Waveguide, Phased Array Antenna, Thermo-Optic Switch, Polymer

  16. Frame-Scheduling for Input-Queued Switches with Energy Reconfiguration Costs

    E-Print Network [OSTI]

    preserving high throughput. The relationship between energy consumption, switch con- figuration and data consumption needed to configure the switching fabric and we assume that the energy depends on the number, power and energy consumption in high speed switches/routers become one of the most critical design

  17. The effects of mobile ATM switches on PNNI peer group operation

    SciTech Connect (OSTI)

    Martinez, L.; Sholander, P.; Tolendino, L.

    1997-04-01T23:59:59.000Z

    This contribution discusses why, and how, mobile networks and mobile switches might be discussed during Phase 1 of the WATM standards process. Next, it reviews mobile routers within Mobile IP. That IP mobility architecture may not apply to the proposed mobile ATM switches. Finally, it discusses problems with PNNI peer group formation and operation when mobile ATM switches are present.

  18. A Novel MEMS LTCC Switch Matrix Bahram Yassini, Savio Choi, Andre Zybura, Ming Yu,

    E-Print Network [OSTI]

    Yu, Ming

    A Novel MEMS LTCC Switch Matrix Bahram Yassini, Savio Choi, Andre Zybura, Ming Yu, Robert. E planar 4x4 switch matrix using microelectromechanical system (MEMS) switches and Low Temperature Cofired Ceramic (LTCC) substrate is presented for the first time. Together a 9-layer LTCC substrate and 32 MEMS

  19. JLA Journal of Legal Analysis Ho, Quinn, Did a Switch in Time Save Nine?

    E-Print Network [OSTI]

    Kammen, Daniel M.

    JLA Journal of Legal Analysis Ho, Quinn, Did a Switch in Time Save Nine? Winter 2010: Volume 2 ~ 1 DiD a Switch in time Save nine?1 Daniel E. Ho2 and Kevin M. Quinn3 AbstrAct Franklin Delano Roosevelt's court-packing plan of 1937 and the "switch in time that saved nine" animate central questions

  20. Dynamic Overlay Single-Domain Contracting for End-to-End Contract-Switching

    E-Print Network [OSTI]

    Yuksel, Murat

    and business relation- ships with other providers as well as users. To allow these much needed economic-switched inter-network will enable flexible and eco- nomically efficient management of risks and value flows as a "packet- switched" network. A contract-switched architecture will enable flexible and eco- nomically

  1. Design and Evaluation of Scalable Switching Fabrics for High-Performance Routers

    E-Print Network [OSTI]

    Tzeng, Nian-Feng

    high scalability and low costs. The considered switching fabrics are based on a multistage structure. The buffered switching fabrics under our consideration are scalable and of low costs, ideally suitable's for packets to move from their arrival LC's toward their destined LC's. Switching fabrics naturally affect

  2. Valuation of Energy Storage: An Optimal Switching Mike Ludkovski

    E-Print Network [OSTI]

    Ludkovski, Mike

    Valuation of Energy Storage: An Optimal Switching Approach Mike Ludkovski Department of Mathematics University, Princeton, NJ 08544 rcarmona@princeton.edu, We consider the valuation of energy storage facilities within the framework of stochastic control. Our two main examples are natural gas dome storage

  3. Optically-initiated silicon carbide high voltage switch

    DOE Patents [OSTI]

    Caporaso, George J. (Livermore, CA); Sampayan, Stephen E. (Manteca, CA); Sullivan, James S. (Livermore, CA); Sanders, David M. (Livermore, CA)

    2012-02-28T23:59:59.000Z

    An improved photoconductive switch having a SIC or other wide band gap substrate material, such as GaAs and field-grading liners composed of preferably SiN formed on the substrate adjacent the electrode perimeters or adjacent the substrate perimeters for grading the electric fields.

  4. Chiral imides as potential chiroptical switches: synthesis and optical properties

    E-Print Network [OSTI]

    Wan, Xin-hua

    Chiral imides as potential chiroptical switches: synthesis and optical properties Erin K. Todd and their electrochemical, absorption, fluorescent, and chiroptical properties were examined for their potential application 613 520 2316; e-mail: wangw@ccs.carleton.ca Tetrahedron Letters 46 (2005) 587590 Tetrahedron Letters

  5. Robust Decentralized Switching Power System Stabilisers for Interconnected

    E-Print Network [OSTI]

    Pota, Himanshu Roy

    ]. In these works, controllers are designed for multi-machine power systems using modern control techniques like system control design; Decentralized control; Switching control; Dwell time; Power system stabilizers. 1. INTRODUCTION The primary task of the power system control is to provide reliable and secure electric power

  6. Identification of Switched MIMO ARX models Laurent Bako1

    E-Print Network [OSTI]

    sys- tems modeling and control [?]. In addition, the increasing emergence of discrete event systems in many modern applications has encouraged the modeling, the estimation and the analysis of such systems adopt a polynomial decoupling representation for han- dling switched systems with multiple inputs

  7. Kalman Filter Constraint Switching for Turbofan Engine Health Estimation

    E-Print Network [OSTI]

    Simon, Dan

    Kalman Filter Constraint Switching for Turbofan Engine Health Estimation Dan Simon Cleveland State Cleveland, Ohio, 44135 Abstract Kalman filters are often used to estimate the state variables of a dynamic system. However, in the application of Kalman filters some known signal information is often either

  8. Title of Dissertation: LASER SWITCHED ELECTRON BEAM MODULATION WITH TERAHERTZ

    E-Print Network [OSTI]

    Anlage, Steven

    ABSTRACT Title of Dissertation: LASER SWITCHED ELECTRON BEAM MODULATION WITH TERAHERTZ APPLICATIONS Jonathan Neumann, PhD 2005 Dissertation Directed By: Dr. Patrick O'Shea, Department of Electrical and Computer Engineering This dissertation describes the exploration of relativistic electron beams modulated

  9. Orbit Correction for the Newly Developed Polarization-Switching Undulator

    SciTech Connect (OSTI)

    Obina, Takashi; Honda, Tohru; Shioya, Tatsuro; Kobayashi, Yukinori; Tsuchiya, Kimichika [Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization, KEK, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Yamamoto, Shigeru [Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization, KEK, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan); Department of Photoscience, Graduate University for Advanced Studies, Shonan Village, Hayama, Kanagawa 240-0193 (Japan)

    2007-01-19T23:59:59.000Z

    A new scheme of undulator magnet arrangements has been proposed and developed as a polarization-switching radiation source, and its test-stand was installed in the 2.5-GeV Photon Factory storage ring (PF ring) in order to investigate the effects on the beam orbit. The closed orbit distortion (COD) over 200 {mu}m was produced in a vertical direction when we switched the polarization of the radiation from the test-stand. In a horizontal direction, the COD was less than 50{mu}m. The results agreed well with the predictions from the magnetic-field measurement on the bench. In order to suppress the CODs and realize a stable operation of the ring with the polarization-switching, we developed an orbit correction system which consists of an encoder to detect motion of magnets, a pair of beam position monitors (BPMs), signal processing parts, and a pair of steering magnets. We succeeded in suppressing the CODs to the level below 3{mu}m using the system even when we switch the polarization at a maximum frequency of 0.8 Hz.

  10. Digital control strategies for switch-mode power supply

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    Digital control strategies for switch-mode power supply Xuefang Lin-Shi, Bruno Allard, Senior and a request for large regulation bandwidth. Digital control is now experi- mented for low-power low control. Fig. 1. Schematic synchronous step-down SMPS Digital control is not new in the field of Power

  11. Magnetic switching, final chapter, Book I: the ATA upgrade prototype

    SciTech Connect (OSTI)

    Birx, D.; Cook, E.; Hawkins, S.; Poor, S.; Reginato, L.; Schmidt, J.; Smith, M.W.

    1983-03-22T23:59:59.000Z

    Efforts directed at finding a 10 kHz switch to replace the current 1 kHz gas blown spark gap have culminated in a prototype for an upgrade of ATA. The design and performance of this prototype as well as possible options and recommendations concerning an eventual upgrade are described. 4 references, 9 figures.

  12. Quantum coherent switch utilizing commensurate nanoelectrode and charge density periodicities

    DOE Patents [OSTI]

    Harrison; Neil (Santa Fe, NM), Singleton; John (Los Alamos, NM), Migliori; Albert (Santa Fe, NM)

    2008-08-05T23:59:59.000Z

    A quantum coherent switch having a substrate formed from a density wave (DW) material capable of having a periodic electron density modulation or spin density modulation, a dielectric layer formed onto a surface of the substrate that is orthogonal to an intrinsic wave vector of the DW material; and structure for applying an external spatially periodic electrostatic potential over the dielectric layer.

  13. Hierarchical Coordinated Freeway On-Ramp Metering Using Switching

    E-Print Network [OSTI]

    Boyer, Edmond

    ]) is taken in this work since linear control tools can be used for analysis and control design. This model). These controllers are designed using switching control theory. A real-data based simulation is used to validate for increasing the effectiveness of the design and the evaluation of traffic monitoring and control is the use

  14. Switching transients in wind farm grids Poul Srensen1)

    E-Print Network [OSTI]

    power collection grid of Nysted offshore wind farm. A number of switching events have been performed of large offshore wind farms have been developed, and there are significant plans for further offshore wind larger wind power installations such as offshore wind farms has increased the focus from TSO's on how

  15. Experimental approaches for the study of hemoglobin switching

    SciTech Connect (OSTI)

    Stamatoyannopoulos, G.; Neinhuis, A.W.

    1985-01-01T23:59:59.000Z

    This book contains papers divided among the following sections: Overview; Globin Gene Structure and Function; Mutations that Influence Hb F Production; Cell Lines Useful for Analysis of Gene Expression; Globin Gene Transfer and Expression; Molecular and Cell Biology of Hematopoiesis; Cell Biology of Switching.

  16. Modeling a Snap-Action, Variable-Delay Switch

    E-Print Network [OSTI]

    Department of Systems Biology, Harvard Medical School, Boston, Massachusetts, United States of America, 2, Cambridge, Massachusetts, United States of America When exposed to tumor necrosis factor (TNF) or TNFModeling a Snap-Action, Variable-Delay Switch Controlling Extrinsic Cell Death John G. Albeck1

  17. ORIGINAL ARTICLE Single ferroelectric-domain photovoltaic switch based

    E-Print Network [OSTI]

    Jo, Moon-Ho

    ORIGINAL ARTICLE Single ferroelectric-domain photovoltaic switch based on lateral BiFeO3 cells Ji serves as a basis for solid-state memory. This phenomenon can also yield an interesting photovoltaic imposed by the ferroelectric polarization vectors. Here, we demonstrate a single-domain photovoltaic

  18. Soft switched high frequency ac-link converter

    E-Print Network [OSTI]

    Balakrishnan, Anand Kumar

    2009-05-15T23:59:59.000Z

    topology for medium and high power ac-ac, ac-dc and dc-ac applications. An ac-link formed by an inductor-capacitor pair replaces the conventional dc-link. Each leg of the converter is formed by two bidirectional switches. Power transfer from input to output...

  19. Energy Aware Computing through Probabilistic Switching: A Study of Limits

    E-Print Network [OSTI]

    Energy Aware Computing through Probabilistic Switching: A Study of Limits Krishna V. Palem, Fellow developed here for building energy-aware networks for computing, using PBITs. Interesting examples thermodynamics and, hence, can serve as a basis for energy-aware computing. While the estimates of the energy

  20. Accurate modeling of switched reluctance machine based on hybrid trained WNN

    SciTech Connect (OSTI)

    Song, Shoujun, E-mail: sunnyway@nwpu.edu.cn; Ge, Lefei; Ma, Shaojie; Zhang, Man [School of Automation, Northwestern Polytechnical University, Xi'an 710072 (China)] [School of Automation, Northwestern Polytechnical University, Xi'an 710072 (China)

    2014-04-15T23:59:59.000Z

    According to the strong nonlinear electromagnetic characteristics of switched reluctance machine (SRM), a novel accurate modeling method is proposed based on hybrid trained wavelet neural network (WNN) which combines improved genetic algorithm (GA) with gradient descent (GD) method to train the network. In the novel method, WNN is trained by GD method based on the initial weights obtained per improved GA optimization, and the global parallel searching capability of stochastic algorithm and local convergence speed of deterministic algorithm are combined to enhance the training accuracy, stability and speed. Based on the measured electromagnetic characteristics of a 3-phase 12/8-pole SRM, the nonlinear simulation model is built by hybrid trained WNN in Matlab. The phase current and mechanical characteristics from simulation under different working conditions meet well with those from experiments, which indicates the accuracy of the model for dynamic and static performance evaluation of SRM and verifies the effectiveness of the proposed modeling method.

  1. Spin-transfer switching of orthogonal spin-valve devices at cryogenic temperatures

    SciTech Connect (OSTI)

    Ye, L., E-mail: ly17@nyu.edu; Gopman, D. B.; Rehm, L.; Backes, D.; Wolf, G.; Kent, A. D. [Department of Physics, New York University, New York, New York 10003 (United States); Ohki, T. [Raytheon BBN Technologies, Cambridge, Massachusetts 02138 (United States); Kirichenko, A. F.; Vernik, I. V.; Mukhanov, O. A. [HYPRES, 175 Clearbrook Road, Elmsford, New York 10523 (United States)

    2014-05-07T23:59:59.000Z

    We present the quasi-static and dynamic switching characteristics of orthogonal spin-transfer devices incorporating an out-of-plane magnetized polarizing layer and an in-plane magnetized spin valve device at cryogenic temperatures. Switching at 12?K between parallel and anti-parallel spin-valve states is investigated for slowly varied current as well as for current pulses with durations as short as 200 ps. We demonstrate 100% switching probability with current pulses 0.6?ns in duration. We also present a switching probability diagram that summarizes device switching operation under a variety of pulse durations, amplitudes, and polarities.

  2. Nanosecond switching in GeSe phase change memory films by atomic force microscopy

    SciTech Connect (OSTI)

    Bosse, James L.; Huey, Bryan D., E-mail: bhuey@ims.uconn.edu [Department of Materials Science and Engineering, 97 North Eagleville Road, Unit 3136, Storrs, Connecticut 06269-3136 (United States); Grishin, Ilya; Kolosov, Oleg V. [Department of Physics, Lancaster University, Lancaster LA1 4YB (United Kingdom); Gyu Choi, Yong [Department of Materials Science and Engineering, Korea Aerospace University, Goyang-si, Gyeonggi-do, 412-791 (Korea, Republic of); Cheong, Byung-ki; Lee, Suyoun [Electronic Materials Research Center, Korea Institute of Science and Technology, Seongbuk-gu, Seoul 136-791 (Korea, Republic of)

    2014-02-03T23:59:59.000Z

    Nanosecond scale threshold switching is investigated with conducting atomic force microscopy (AFM) for an amorphous GeSe film. Switched bits exhibit 23 orders of magnitude variations in conductivity, as demonstrated in phase change based memory devices. Through the nm-scale AFM probe, this crystallization was achieved with pulse durations of as low as 15?ns, the fastest reported with scanning probe based methods. Conductance AFM imaging of the switched bits further reveals correlations between the switched volume, pulse amplitude, and pulse duration. The influence of film heterogeneities on switching is also directly detected, which is of tremendous importance for optimal device performance.

  3. Microwave pulse compression from a storage cavity with laser-induced switching

    DOE Patents [OSTI]

    Bolton, Paul R. (Menlo Park, CA)

    1992-01-01T23:59:59.000Z

    A laser-induced switch and a multiple cavity configuration are disclosed for producing high power microwave pulses. The microwave pulses are well controlled in wavelength and timing, with a quick rise time and a variable shape and power of the pulse. In addition, a method of reducing pre-pulse leakage to a low level is disclosed. Microwave energy is directed coherently to one or more cavities that stores the energy in a single mode, represented as a standing wave pattern. In order to switch the stored microwave energy out of the main cavity and into the branch waveguide, a laser-actuated switch is provided for the cavity. The switch includes a laser, associated optics for delivering the beam into the main cavity, and a switching gas positioned at an antinode in the main cavity. When actuated, the switching gas ionizes, creating a plasma, which becomes reflective to the microwave energy, changing the resonance of the cavity, and as a result the stored microwave energy is abruptly switched out of the cavity. The laser may directly pre-ionize the switching gas, or it may pump an impurity in the switching gas to an energy level which switches when a pre-selected cavity field is attained. Timing of switching the cavities is controlled by varying the pathlength of the actuating laser beam. For example, the pathlengths may be adjusted to output a single pulse of high power, or a series of quick lower power pulses.

  4. Reversible piezomagnetoelectric switching in bulk polycrystalline ceramics

    SciTech Connect (OSTI)

    Stevenson, T., E-mail: t.j.stevenson@leeds.ac.uk; Bennett, J.; Brown, A. P.; Wines, T.; Bell, A. J.; Comyn, T. P. [Institute for Materials Research, University of Leeds, Leeds LS2 9JT (United Kingdom); Smith, R. I. [ISIS Neutron Facility, Rutherford Appleton Laboratory, Didcot OX11 0QX (United Kingdom)

    2014-08-01T23:59:59.000Z

    Magnetoelectric (ME) coupling in materials offer tremendous advantages in device functionality enabling technologies including advanced electronic memory, combining electronic speed, and efficiency with magnetic robustness. However, low cost polycrystalline ME materials are excluded from most commercial applications, operating only at cryogenic temperatures, impractically large electric/magnetic fields, or with low ME coefficients (1-100 mV/cm?Oe). Despite this, the technological potential of single compound ME coupling has continued to drive research into multiferroics over the last two decades. Here we show that by manipulating the large induced atomic strain within the polycrystalline, room temperature multiferroic compound 0.7BiFeO{sub 3}0.3PbTiO{sub 3}, we can induce a reversible, piezoelectric strain controlled ME effect. Employing an in situ neutron diffraction experiment, we have demonstrated that this piezomagnetoelectric effect manifests with an applied electric field >8 kV/mm at the onset of piezoelectric strain, engineered in to the compound by crystallographic phase mixing. This produces a remarkable intrinsic ME coefficient of 1276 mV/cm?Oe, due to a strain driven modification to the oxygen sub-lattice, inducing an increase in magnetic moment per Fe{sup 3+} ion of +0.142 ?{sub B}. This work provides a framework for investigations into strain engineered nanostructures to realize low-cost ME devices designed from the atoms up, as well as contributing to the deeper understanding of single phase ME coupling mechanisms.

  5. Interprocessor bus switching system for simultaneous communication in plural bus parallel processing system

    DOE Patents [OSTI]

    Atac, Robert (Aurora, IL); Fischler, Mark S. (Warrenville, IL); Husby, Donald E. (DeKalb, IL)

    1991-01-01T23:59:59.000Z

    A bus switching apparatus and method for multiple processor computer systems comprises a plurality of bus switches interconnected by branch buses. Each processor or other module of the system is connected to a spigot of a bus switch. Each bus switch also serves as part of a backplane of a modular crate hardware package. A processor initiates communication with another processor by identifying that other processor. The bus switch to which the initiating processor is connected identifies and secures, if possible, a path to that other processor, either directly or via one or more other bus switches which operate similarly. If a particular desired path through a given bus switch is not available to be used, an alternate path is considered, identified and secured.

  6. Spontaneous symmetry breaking in 2D: Kibble-Zurek mechanism in temperature quenched colloidal monolayers

    E-Print Network [OSTI]

    Patrick Dillmann; Georg Maret; Peter Keim

    2014-09-16T23:59:59.000Z

    The Kibble-Zurek mechanism describes the formation of topological defects during spontaneous symmetry breaking for quite different systems. Shortly after the big bang, the isotropy of the Higgs-field is broken during the expansion and cooling of the universe. Kibble proposed the formation of monopoles, strings, and membranes in the Higgs field since the phase of the symmetry broken field can not switch globally to gain the same value everywhere in space. Zurek pointed out that the same mechanism is relevant for second order phase transitions in condensed matter systems. Every finite cooling rate induces the system to fall out of equilibrium which is due to the critical slowing down of order parameter fluctuations: the correlation time diverges and the symmetry of the system can not change globally but incorporates defects between different domains. Depending on the cooling rate the heterogeneous order parameter pattern are a fingerprint of critical fluctuations. In the present manuscript we show that a monolayer of superparamagnetic colloidal particles is ideally suited to investigate such phenomena. In thermal equilibrium the system undergos continuous phase transitions according KTHNY-theory. If cooled rapidly across the melting temperature the final state is a polycrystal. We show, that the observations can not be explained with nucleation of a supercooled fluid but is compatible with the Kibble-Zurek mechanism.

  7. 1486 IEEE TRANSACTIONS ON AUTOMATIC CONTROL, VOL. 51, NO. 9, SEPTEMBER 2006 Accessibility of Switched Linear Systems

    E-Print Network [OSTI]

    Wang, Yuan

    the controllability of switched linear sys- tems. The structure of accessibility Lie algebra is revealed. Some accessi or normal) controllability of a large class of switched linear systems are obtained. Index Terms--Accessibility, controllability, Lie algebra, switched linear system. I. INTRODUCTION Consider a switched linear system _x(t) = A

  8. On the mechanisms of switching between two steady states of electroconductivity in plasticized transparent PVC films

    E-Print Network [OSTI]

    D. V. Vlasov; L. A. Apresian; V. I. Krystob; T. V. Vlasova

    2010-03-29T23:59:59.000Z

    The results of experimental researches of electroconductivity of PVC films, plasticized by patented modifier, at fields below the breakdown level are described. A possibility of management of the repeated transitions between two states with high and relatively low conductivity with conservation of reversibility is found out. A simple qualitative model of abnormal conductivity based on representation of polymer film as a sequence p-n of transitions is offered. For samples of plasticized PVC films with thickness 30-50 microns specific volume resistance of steady states was of an order of 10E4 Om*m \\times 10E6 Om*m, accordingly. A simple qualitative model describing abnormal character of conductivity of polymeric films is offered. The model considers the presence of known non-uniform plasticized polymer structure with discrete domains in which quasi-free moving of charges can occur. At imposing of an external field semi-condictive domains form sequence of p-n transitions which provides presence of two states of conductivity, in analogy with dinistors.

  9. Micro-opto-mechanical switching and tuning for integrated optical systems

    E-Print Network [OSTI]

    Nielson, Gregory Nolan, 1974-

    2004-01-01T23:59:59.000Z

    Integrated optical circuits have the potential to lower manufacturing and operating costs and enhance the functionality of optical systems in a manner similar to what has been achieved by integrating electronic circuits. ...

  10. Magnetization switching of rare earth orthochromite CeCrO{sub 3}

    SciTech Connect (OSTI)

    Cao, Yiming; Cao, Shixun, E-mail: sxcao@shu.edu.cn; Ren, Wei; Feng, Zhenjie; Yuan, Shujuan; Kang, Baojuan; Zhang, Jincang [Department of Physics, Shanghai University, Shanghai 200444 (China); Lu, Bo [Laboratory for Microstructures, Shanghai University, Shanghai 200444 (China)

    2014-06-09T23:59:59.000Z

    We report the synthesis of single phase rare earth orthochromite CeCrO{sub 3} and its magnetic properties. A canted antiferromagnetic transition with thermal hysteresis at T?=?260?K is observed, and a magnetic compensation (zero magnetization) near 133?K is attributed to the antiparallel coupling between Ce{sup 3+} and Cr{sup 3+} moments. At low temperature, field induced magnetization reversal starting from 43?K for H?=?1.2 kOe reveals the spin flip driven by Zeeman energy between the net moments and the applied field. These findings may find potential uses in magnetic switching devices such as nonvolatile magnetic memory which facilitates two distinct states of magnetization.

  11. Electric field controlled reversible magnetic anisotropy switching studied by spin rectification

    SciTech Connect (OSTI)

    Zhou, Hengan; Fan, Xiaolong, E-mail: fanxiaolong@lzu.edu.cn; Wang, Fenglong; Jiang, Changjun; Rao, Jinwei; Zhao, Xiaobing; Xue, Desheng [Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China)] [Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Gui, Y. S.; Hu, C.-M. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)] [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)

    2014-03-10T23:59:59.000Z

    In this letter, spin rectification was used to study the electric field controlled dynamic magnetic properties of the multiferroic composite which is a Co stripe with induced in-plane anisotropy deposited onto a Pb(Mg{sub 1?3}Nb{sub 2?3})O{sub 3}-PbTiO{sub 3} substrate. Due to the coupling between piezoelectric and magnetoelastic effects, a reversible in-plane anisotropy switching has been realized by varying the history of the applied electric field. This merit results from the electric hysteresis of the polarization in the nonlinear piezoelectric regime, which has been proved by a butterfly type electric field dependence of the in-plane anisotropy field. Moreover, the electric field dependent effective demagnetization field and linewidth have been observed at the same time.

  12. Plasma Switch for High-Power Active Pulse Compressor

    SciTech Connect (OSTI)

    Hirshfield, Jay L. [Omega-P, Inc.] [Omega-P, Inc.

    2013-11-04T23:59:59.000Z

    Results are presented from experiments carried out at the Naval Research Laboratory X-band magnicon facility on a two-channel X-band active RF pulse compressor that employed plasma switches. Experimental evidence is shown to validate the basic goals of the project, which include: simultaneous firing of plasma switches in both channels of the RF circuit, operation of quasi-optical 3-dB hybrid directional coupler coherent superposition of RF compressed pulses from both channels, and operation of the X-band magnicon directly in the RF pulse compressor. For incident 1.2 ?s pulses in the range 0.63 ? 1.35 MW, compressed pulses of peak powers 5.7 ? 11.3 MW were obtained, corresponding to peak power gain ratios of 8.3 ? 9.3. Insufficient bakeout and conditioning of the high-power RF circuit prevented experiments from being conducted at higher RF input power levels.

  13. Electro-optical switching and memory display device

    DOE Patents [OSTI]

    Skotheim, T.A.; O'Grady, W.E.; Linkous, C.A.

    1983-12-29T23:59:59.000Z

    An electro-optical display device having a housing with wall means including one transparent wall and at least one other wall. Counter electrodes are positioned on the transparent wall and display electrodes are positioned on the other wall with both electrodes in electrically conductive relationship with an electrolyte. Circuits means are connected to the display and counter electrodes to apply different predetermined control potentials between them. The display electrodes are covered with a thin electrically conductive polymer film that is characterized according to the invention by having embedded in it pigment molecules as counter ions. The display device is operable to be switched to a plurality of different visual color states at an exceptionally rapid switching rate while each of the color states is characterized by possessing good color intensity and definition.

  14. Methods for batch fabrication of cold cathode vacuum switch tubes

    DOE Patents [OSTI]

    Walker, Charles A. (Albuquerque, NM); Trowbridge, Frank R. (Albuquerque, NM)

    2011-05-10T23:59:59.000Z

    Methods are disclosed for batch fabrication of vacuum switch tubes that reduce manufacturing costs and improve tube to tube uniformity. The disclosed methods comprise creating a stacked assembly of layers containing a plurality of adjacently spaced switch tube sub-assemblies aligned and registered through common layers. The layers include trigger electrode layer, cathode layer including a metallic support/contact with graphite cathode inserts, trigger probe sub-assembly layer, ceramic (e.g. tube body) insulator layer, and metallic anode sub-assembly layer. Braze alloy layers are incorporated into the stacked assembly of layers, and can include active metal braze alloys or direct braze alloys, to eliminate costs associated with traditional metallization of the ceramic insulator layers. The entire stacked assembly is then heated to braze/join/bond the stack-up into a cohesive body, after which individual switch tubes are singulated by methods such as sawing. The inventive methods provide for simultaneously fabricating a plurality of devices as opposed to traditional methods that rely on skilled craftsman to essentially hand build individual devices.

  15. Active high-power RF switch and pulse compression system

    DOE Patents [OSTI]

    Tantawi, Sami G. (San Mateo, CA); Ruth, Ronald D. (Woodside, CA); Zolotorev, Max (Mountain View, CA)

    1998-01-01T23:59:59.000Z

    A high-power RF switching device employs a semiconductor wafer positioned in the third port of a three-port RF device. A controllable source of directed energy, such as a suitable laser or electron beam, is aimed at the semiconductor material. When the source is turned on, the energy incident on the wafer induces an electron-hole plasma layer on the wafer, changing the wafer's dielectric constant, turning the third port into a termination for incident RF signals, and. causing all incident RF signals to be reflected from the surface of the wafer. The propagation constant of RF signals through port 3, therefore, can be changed by controlling the beam. By making the RF coupling to the third port as small as necessary, one can reduce the peak electric field on the unexcited silicon surface for any level of input power from port 1, thereby reducing risk of damaging the wafer by RF with high peak power. The switch is useful to the construction of an improved pulse compression system to boost the peak power of microwave tubes driving linear accelerators. In this application, the high-power RF switch is placed at the coupling iris between the charging waveguide and the resonant storage line of a pulse compression system. This optically controlled high power RF pulse compression system can handle hundreds of Megawatts of power at X-band.

  16. 4 ESS (trademark) switch electromagnetic-pulse assessment. Volume 2. Task 3 laboratory testing of the 4 ESS Switch. Final report

    SciTech Connect (OSTI)

    Not Available

    1989-12-01T23:59:59.000Z

    The 4ESS Switch was subjected to test sequences representative of electromagnetic stresses following a high-altitude nuclear blast. These laboratory tests revealed some potential equipment sensitivities requiring only minor modifications. With these modifications implemented, the 4 ESS Switch demonstrated considerable robustness in servicing calls following current injection stress. (jhd)

  17. Effect of switching control strategies on the energy performance of electrochromic windows

    SciTech Connect (OSTI)

    Sullivan, R.; Lee, E.S.; Papamichael, K.; Rubin, M.; Selkowitz, S. [Lawrence Berkeley Lab., CA (United States). Building Technologies Program

    1994-04-01T23:59:59.000Z

    This paper presents the results of a study investigating the energy performance of electrochromic windows under a variety of state-switching control strategies. The authors used the DOE-2.1E energy simulation program to analyze the annual cooling, lighting, and total electricity use and peak demand as a function of glazing type, size, and electrochromic control strategy. They simulated a prototypical commercial office building module located in the cooling-dominated location of Blythe, California. Control strategies analyzed were based on daylight illuminance, incident total solar radiation, and space cooling load. Their results show that when a daylighting strategy is used to reduce electrical lighting requirements, control algorithms based on daylight illuminance results in the best overall annual energy performance. If daylighting is not a design option, controls based on space cooling load yield the best performance through solar heat gain reduction. The performance of the incident total solar radiation control strategies varies as a function of the values of solar radiation which trigger the bleached and colored states of the electrochromic (setpoint range); for small to moderate window sizes which result in small to moderate solar gains, a large setpoint-range was best since it provides increased illuminance for daylighting without much cooling penalty; for larger window sizes, which provide adequate daylight, a small setpoint-range was best to reduce unwanted solar heat gains and the consequential increased cooling requirement. Of particular importance is the fact that reduction in peak electric demand was found to be independent of the type of control strategy used for electrochromic switching. This is because the electrochromics are generally in their most colored state under peak conditions, and the mechanism used for achieving such a state is not important.

  18. Computational mechanics

    SciTech Connect (OSTI)

    Goudreau, G.L.

    1993-03-01T23:59:59.000Z

    The Computational Mechanics thrust area sponsors research into the underlying solid, structural and fluid mechanics and heat transfer necessary for the development of state-of-the-art general purpose computational software. The scale of computational capability spans office workstations, departmental computer servers, and Cray-class supercomputers. The DYNA, NIKE, and TOPAZ codes have achieved world fame through our broad collaborators program, in addition to their strong support of on-going Lawrence Livermore National Laboratory (LLNL) programs. Several technology transfer initiatives have been based on these established codes, teaming LLNL analysts and researchers with counterparts in industry, extending code capability to specific industrial interests of casting, metalforming, and automobile crash dynamics. The next-generation solid/structural mechanics code, ParaDyn, is targeted toward massively parallel computers, which will extend performance from gigaflop to teraflop power. Our work for FY-92 is described in the following eight articles: (1) Solution Strategies: New Approaches for Strongly Nonlinear Quasistatic Problems Using DYNA3D; (2) Enhanced Enforcement of Mechanical Contact: The Method of Augmented Lagrangians; (3) ParaDyn: New Generation Solid/Structural Mechanics Codes for Massively Parallel Processors; (4) Composite Damage Modeling; (5) HYDRA: A Parallel/Vector Flow Solver for Three-Dimensional, Transient, Incompressible Viscous How; (6) Development and Testing of the TRIM3D Radiation Heat Transfer Code; (7) A Methodology for Calculating the Seismic Response of Critical Structures; and (8) Reinforced Concrete Damage Modeling.

  19. Computational mechanics

    SciTech Connect (OSTI)

    Raboin, P J

    1998-01-01T23:59:59.000Z

    The Computational Mechanics thrust area is a vital and growing facet of the Mechanical Engineering Department at Lawrence Livermore National Laboratory (LLNL). This work supports the development of computational analysis tools in the areas of structural mechanics and heat transfer. Over 75 analysts depend on thrust area-supported software running on a variety of computing platforms to meet the demands of LLNL programs. Interactions with the Department of Defense (DOD) High Performance Computing and Modernization Program and the Defense Special Weapons Agency are of special importance as they support our ParaDyn project in its development of new parallel capabilities for DYNA3D. Working with DOD customers has been invaluable to driving this technology in directions mutually beneficial to the Department of Energy. Other projects associated with the Computational Mechanics thrust area include work with the Partnership for a New Generation Vehicle (PNGV) for ''Springback Predictability'' and with the Federal Aviation Administration (FAA) for the ''Development of Methodologies for Evaluating Containment and Mitigation of Uncontained Engine Debris.'' In this report for FY-97, there are five articles detailing three code development activities and two projects that synthesized new code capabilities with new analytic research in damage/failure and biomechanics. The article this year are: (1) Energy- and Momentum-Conserving Rigid-Body Contact for NIKE3D and DYNA3D; (2) Computational Modeling of Prosthetics: A New Approach to Implant Design; (3) Characterization of Laser-Induced Mechanical Failure Damage of Optical Components; (4) Parallel Algorithm Research for Solid Mechanics Applications Using Finite Element Analysis; and (5) An Accurate One-Step Elasto-Plasticity Algorithm for Shell Elements in DYNA3D.

  20. Thermally activated switching of perpendicular magnet by spin-orbit spin torque

    SciTech Connect (OSTI)

    Lee, Ki-Seung [Department of Materials Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Spin Convergence Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Lee, Seo-Won [Department of Materials Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Min, Byoung-Chul [Spin Convergence Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Lee, Kyung-Jin, E-mail: kj-lee@korea.ac.kr [Department of Materials Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Spin Convergence Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 136-713 (Korea, Republic of)

    2014-02-17T23:59:59.000Z

    We theoretically investigate the threshold current for thermally activated switching of a perpendicular magnet by spin-orbit spin torque. Based on the Fokker-Planck equation, we obtain an analytic expression of the switching current, in agreement with numerical result. We find that thermal energy barrier exhibits a quasi-linear dependence on the current, resulting in an almost linear dependence of switching current on the log-scaled current pulse-width even below 10?ns. This is in stark contrast to standard spin torque switching, where thermal energy barrier has a quadratic dependence on the current and the switching current rapidly increases at short pulses. Our results will serve as a guideline to design and interpret switching experiments based on spin-orbit spin torque.

  1. An investigation of irregular switching in three phase adjustable speed motor drives without neutral connection

    E-Print Network [OSTI]

    1990-01-01T23:59:59.000Z

    ELIMINATION OF SWITCHING IRREG ULARITIES . . CHAPTER Page V. l Two Independent Current Controller . . V. 2 Controlling the Duration of Null State 44 V. 3 Applying Hysteresis Control on Error Current V. 4 Elimination oi' Null Switching State 45 V. 5... it possible to overcome these limitations of dc machine, by using a, high performance ac motor drive. Most of these motor drives utilize a, current controller which attempts to switch a pulse width modulated voltage source inverter to force the motor...

  2. a-site molecular switches: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of parameters. Agata Checinska; Felix A. Pollock; Libby Heaney; Ahsan Nazir 2015-02-11 6 Engineering Protein Molecular Switches To Regulate Gene Expression with Small Molecules....

  3. Thermal Transistor: Heat Flux Switching and Modulating Wei Chung LO1;4

    E-Print Network [OSTI]

    Li, Baowen

    is an efficient heat control device which can act as a heat switch as well as a heat modulator. In this paper, we

  4. Coherent-feedback control strategy to suppress spontaneous switching in ultra-low power optical bistability

    E-Print Network [OSTI]

    Hideo Mabuchi

    2011-01-18T23:59:59.000Z

    An optical resonator with intracavity Kerr nonlinearity can exhibit dispersive bistability suitable for all-optical switching. With nanophotonic elements it may be possible to achieve attojoule switching energies, which would be very attractive for ultra-low power operation but potentially problematic because of quantum fluctuation-induced spontaneous switching. In this manuscript I derive a quantum-optical model of two Kerr-nonlinear ring resonators connected in a coherent feedback loop, and show via numerical simulation that a properly designed `controller' cavity can significantly reduce the spontaneous switching rate of a bistable `plant' cavity in a completely embedded and autonomous manner.

  5. Near-Infrared Electrochromic and Chiroptical Switching Materials: Design, Synthesis, and Characterization of Chiral Organogels

    E-Print Network [OSTI]

    Wan, Xin-hua

    Near-Infrared Electrochromic and Chiroptical Switching Materials: Design, Synthesis regions have been realized using a low molecular weight gel as a chiral scaffold and electrochromic

  6. 14 ESS (trademark) switch inherent radiation-hardness assessment. Volume 1. Final report

    SciTech Connect (OSTI)

    Not Available

    1990-07-01T23:59:59.000Z

    The objective of Phase I of the 4 ESS Switch RHA Program documented in this report is the preliminary assessment of the inherent fallout-radiation susceptibility of the 4 ESS Switch. The approach described herein consists of the identification of the active microelectronic piece-parts used in the 4 ESS Switch; characterization of their radiation tolerance, based on available data; preliminary identification of hardness-critical packs; and preliminary analysis of 4 ESS Switch performance during expose to ambient (unshielded) fallout radiation, also based on available data. (Author)

  7. Filament-Filament Switching Can Be Regulated by Separation Between Filaments Together with Cargo Motor Number

    E-Print Network [OSTI]

    Erickson, Robert P; Gross, Steven P; Yu, Clare C; Kabla, Alexandre J

    2013-01-01T23:59:59.000Z

    that a single engaged motor cannot switch between filaments.EL, Goldman YE (2010) Motor number controls cargo switchingtransport: molecular motors navigate a complex cytoskeleton.

  8. High-current, fast-switching transistor development

    SciTech Connect (OSTI)

    Hower, P.L.

    1981-03-15T23:59:59.000Z

    Work that shows how the results obtained under a previous contract (NAS3-18916) have been applied to a larger-diameter (33-mm) transistor are described. An improved base contact for equalizing the base-emitter voltage at high currents has been developed along with an improved emitter contact preform which increases the silicon area available for current conduction. The electrical performance achieved is consistent with the proposed optimum design. The device design, wafer-processing techniques, and various measurements which include forward SOA, dc characteristics, and switching times are described.

  9. Klystron switching power supplies for the Internation Linear Collider

    SciTech Connect (OSTI)

    Fraioli, Andrea; /Cassino U. /INFN, Pisa

    2009-12-01T23:59:59.000Z

    The International Linear Collider is a majestic High Energy Physics particle accelerator that will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. ILC will complement the Large Hadron Collider (LHC), a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, by producing electron-positron collisions at center of mass energy of about 500 GeV. In particular, the subject of this dissertation is the R&D for a solid state Marx Modulator and relative switching power supply for the International Linear Collider Main LINAC Radio Frequency stations.

  10. Lyons Switch, Oklahoma: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere I Geothermal Pwer Plant Jump to:LandownersLuther, Oklahoma: Energy ResourcesLyon County,DevelopmentSwitch,

  11. Commute Mode Switching Impact Tool | Department of Energy

    Office of Environmental Management (EM)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742 33 111 1,613PortsmouthBartlesville EnergyDepartment. CashDay-JuneOfficeFresnoCommute Mode Switching

  12. Dynamic Switching of the Spin Circulation in Tapered Magnetic Nanodisks

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625govInstrumentstdmadapInactiveVisitingContract ManagementDiscovering HowAnaDynamic Switching of the Spin Circulation

  13. Prey switching with a linear preference trade-off

    E-Print Network [OSTI]

    S. H. Piltz; M. A. Porter; P. K. Maini

    2013-02-25T23:59:59.000Z

    In ecology, prey switching refers to a predator's adaptive change of habitat or diet in response to prey abundance. In this paper, we study piecewise-smooth models of predator-prey interactions with a linear trade-off in a predator's prey preference. We consider optimally foraging predators and derive a model for a 1 predator-2 prey interaction with a tilted switching manifold between the two sides of discontinuous vector fields. We show that the 1 predator-2 prey system undergoes a novel adding-sliding-like (center to two-part periodic orbit; "C2PO") bifurcation in which the prey ratio transitions from constant to time-dependent. Further away from the bifurcation point, the period of the oscillating prey ratio period doubles, suggesting a possible cascade to chaos. We compare our model predictions with data and demonstrate that we successfully capture the periodicity in the ratio between the predator's preferred and alternative prey types in data on freshwater plankton. Our study suggests that it is useful to investigate prey ratio as a possible indicator of how population dynamics can be influenced by ecosystem diversity.

  14. Electrically operated magnetic switch designed to display reduced leakage inductance

    DOE Patents [OSTI]

    Cook, E.G.

    1994-05-10T23:59:59.000Z

    An electrically operated magnetic switch is disclosed herein for use in opening and closing a circuit between two terminals depending upon the voltage across these terminals. The switch so disclosed is comprised of a ferrite core in the shape of a toroid having opposing ends and opposite inner and outer sides and an arrangement of electrically conductive components defining at least one current flow path which makes a number of turns around the core. This arrangement of components includes a first plurality of electrically conducive rigid rods parallel with and located outside the outer side of the core and a second plurality of electrically conductive rigid rods parallel with and located inside the inner side of the core. The arrangement also includes means for electrically connecting these rods together so that the define the current flow path. In one embodiment, this latter means uses rigid cross-tab means. In another, preferred embodiment, printed circuits on rigid dielectric substrates located on opposite ends of the core are utilized to interconnect the rods together. 10 figures.

  15. Electrically operated magnetic switch designed to display reduced leakage inductance

    DOE Patents [OSTI]

    Cook, Edward G. (Livermore, CA)

    1994-01-01T23:59:59.000Z

    An electrically operated magnetic switch is disclosed herein for use in opening and closing a circuit between two terminals depending upon the voltage across these terminals. The switch so disclosed is comprised of a ferrite core in the shape of a toroid having opposing ends and opposite inner and outer sides and an arrangement of electrically conductive components defining at least one current flow path which makes a number of turns around the core. This arrangement of components includes a first plurality of electrically conducive rigid rods parallel with and located outside the outer side of the core and a second plurality of electrically conductive rigid rods parallel with and located inside the inner side of the core. The arrangement also includes means for electrically connecting these rods together so that the define the current flow path. In one embodiment, this latter means uses rigid cross-tab means. In another, preferred embodiment, printed circuits on rigid dielectric substrates located on opposite ends of the core are utilized to interconnect the rods together.

  16. Optimization of radio astronomical observations using Allan variance measurements

    E-Print Network [OSTI]

    R. Schieder; C. Kramer

    2001-05-04T23:59:59.000Z

    Stability tests based on the Allan variance method have become a standard procedure for the evaluation of the quality of radio-astronomical instrumentation. They are very simple and simulate the situation when detecting weak signals buried in large noise fluctuations. For the special conditions during observations an outline of the basic properties of the Allan variance is given, and some guidelines how to interpret the results of the measurements are presented. Based on a rather simple mathematical treatment clear rules for observations in ``Position-Switch'', ``Beam-'' or ``Frequency-Switch'', ``On-The-Fly-'' and ``Raster-Mapping'' mode are derived. Also, a simple ``rule of the thumb'' for an estimate of the optimum timing for the observations is found. The analysis leads to a conclusive strategy how to plan radio-astronomical observations. Particularly for air- and space-borne observatories it is very important to determine, how the extremely precious observing time can be used with maximum efficiency. The analysis should help to increase the scientific yield in such cases significantly.

  17. Switching algorithms for extending battery life in Electric Vehicles Ron Adany a,*, Doron Aurbach b

    E-Print Network [OSTI]

    Kraus, Sarit

    27 December 2012 Keywords: Electric Vehicles (EV) Switching algorithms Battery life Lithium ionSwitching algorithms for extending battery life in Electric Vehicles Ron Adany a,*, Doron Aurbach b Department of Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel h i g h l i g h t s battery's life

  18. Minimizing Simultaneous Switching Noise at Reduced Power with Power Transmission Lines for

    E-Print Network [OSTI]

    Swaminathan, Madhavan

    Minimizing Simultaneous Switching Noise at Reduced Power with Power Transmission Lines for High] by replacing the power plane structure with a power transmission line (PTL). In this paper, a new power switching noise; power transmission line I. INTRODUCTION The rapid increase in data rates and transistor

  19. Integration of planar transformer and/or planar inductor with power switches in power converter

    DOE Patents [OSTI]

    Chen, Kanghua (Canton, MI); Ahmed, Sayeed (Canton, MI); Zhu, Lizhi (Canton, MI)

    2007-10-30T23:59:59.000Z

    A power converter integrates at least one planar transformer comprising a multi-layer transformer substrate and/or at least one planar inductor comprising a multi-layer inductor substrate with a number of power semiconductor switches physically and thermally coupled to a heat sink via one or more multi-layer switch substrates.

  20. Generic and Unified Model of Switched Capacitor Converters Sam Ben-Yaakov

    E-Print Network [OSTI]

    @ee.bgu.ac.il Website: www.ee.bgu.ac.il/~pel/ Abstract -- A generic modeling methodology that analyzes the losses analytical approach is unified, covering both hard and soft switched SCC topologies. The major advantage in the optimization of SCC systems and their control to achieve desired regulations. I. INTRODUCTION Switched

  1. Electrochemical control of quantum interference in anthraquinone-based molecular switches

    E-Print Network [OSTI]

    Thygesen, Kristian

    Electrochemical control of quantum interference in anthraquinone-based molecular switches Troels properties of a recently proposed anthraquinone-based electrochemical switch. Robust conductance on in the anthraquinone but absent in the hydroquinone molecular bridge. A simple explanation of the interference effect

  2. An LQ sub-optimal stabilizing feedback law for switched linear systems

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    An LQ sub-optimal stabilizing feedback law for switched linear systems P. Riedinger J.-C. Vivalda linear switched system based on the optimization of a quadratic criterion. The main result provides is a challenging task. LQ regulators are widely used for the control of linear systems because of their simple

  3. Active Bank Switching for Temperature Control of the Register File in a Microprocessor

    E-Print Network [OSTI]

    Pedram, Massoud

    Active Bank Switching for Temperature Control of the Register File in a Microprocessor Kimish Patel, called active bank switching, for temperature control in the register file of a microprocessor to microprocessor performance and a significant component of its cost. Expensive packaging and heat removal

  4. Author's personal copy Phase locking of short-pulse Q-switched lasers

    E-Print Network [OSTI]

    Author's personal copy Phase locking of short-pulse Q-switched lasers Fanting Kong a , Liping Liu]. In short-pulse lasers, however, the conditions for phase locking differ from those of the continuous t The effects of frequency mismatch on phase locking of two passively Q-switched lasers have been stud- ied

  5. A numerical framework for optimal control of switched affine systems with state

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    A numerical framework for optimal control of switched affine systems with state constraint Pierre optimal control, switched systems, complementarity systems, numerical method 1. INTRODUCTION Most of the results related to the optimal control of hybrid systems deal with subsystems sharing zero as common

  6. Characterization of the conduction phase of a plasma opening switch using a hydrogen plasma

    E-Print Network [OSTI]

    Characterization of the conduction phase of a plasma opening switch using a hydrogen plasma J. J Pulsed Power Physics Branch, Plasma Physics Division, Naval Research Laboratory, Washington, D.C. 20375 Y 2004; published online 7 January 2005) Plasma opening switch (POS) experiments were conducted

  7. Switched system modeling and robust steering control in a hot strip mill

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    Switched system modeling and robust steering control in a hot strip mill I. Malloci J. Daafouz C. Abstract: In this article, a robust steering control for the last phase of the rolling process in a hot. The switchings make the system unstable and the task of the tail end steering control consists in guaranteeing

  8. PERFORMANCE ENHANCEMENT OF WIND TURBINE POWER REGULATION BY SWITCHED LINEAR CONTROL

    E-Print Network [OSTI]

    Duffy, Ken

    PERFORMANCE ENHANCEMENT OF WIND TURBINE POWER REGULATION BY SWITCHED LINEAR CONTROL D.J.Leith W Power regulation of horizontal-axis grid-connected up-wind constant-speed pitch-regulated wind turbines ENHANCEMENT OF WIND TURBINE POWER REGULATION BY SWITCHED LINEAR CONTROL D.J.Leith W.E.Leithead Department

  9. ADAPTIVE SWITCHING IN PRACTICE: IMPROVING MYOELECTRIC PROSTHESIS PERFORMANCE THROUGH REINFORCEMENT LEARNING

    E-Print Network [OSTI]

    Sutton, Richard S.

    ADAPTIVE SWITCHING IN PRACTICE: IMPROVING MYOELECTRIC PROSTHESIS PERFORMANCE THROUGH REINFORCEMENT, each muscle site directly controls one motion of the prosthesis, and various methods of switching can be used as needed to control additional motions of the prosthesis [1] [2] [3]. Some state

  10. Switch-reference and Omotic-Cushitic Language Contact in Southwest Ethiopia Yvonne Treis

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    1 Switch-reference and Omotic-Cushitic Language Contact in Southwest Ethiopia Yvonne Treis LLACAN. This study shows that there is a confined area in the South of Ethiopia where many Omotic languages and a few (Cushitic) and gives an overview of the distribution of switch-reference systems in Ethiopia in general

  11. Millisecond switching in solid state electrochromic polymer devices fabricated from ionic self-assembled multilayers

    E-Print Network [OSTI]

    Heflin, Randy

    Millisecond switching in solid state electrochromic polymer devices fabricated from ionic self The electrochromic switching times of solid state conducting polymer devices fabricated by the ionic self shown to decrease with the active area of the electrochromic device suggesting that even faster

  12. Solid-State Gadolinium-Magnesium Hydride Optical Switch R. Armitage

    E-Print Network [OSTI]

    -state electrochromic device. With positive polarization of the hydride electrode, the visible reflectance approaches 35 and reflecting states. Keywords: gadolinium-magnesium; electrochromic hydride; optical switching device. 2 #12;A conventional electrochromics5 . Optical switching has also been demonstrated by varying the H content

  13. Robust optimal switching control for nonlinear Joseph A. Ball, Jerawan Chudoung and Martin V. Day

    E-Print Network [OSTI]

    Day, Martin

    be solved by a direct geometric construction. Key Words. running cost, switching cost, worst settings and with costs assigned to switching of controls. We formulate the problem both in an L2-gain is the deterministic unknown disturbance, and z(t) IR is the cost function. We assume that the set A of admissible

  14. Polyimide-waveguide-based thermal optical switch using total-internal-reflection effect

    E-Print Network [OSTI]

    Chen, Ray

    Polyimide-waveguide-based thermal optical switch using total-internal-reflection effect Jianyi Yang with an X junction was designed and fabricated by using the thermo-optic effect of polyimide materials and fabricated the TIR TO switch us- ing polyimide materials. The TO effect of polymeric materials is negative, i

  15. Energy Metering for Free: Augmenting Switching Regulators for Real-Time Monitoring

    E-Print Network [OSTI]

    Energy Metering for Free: Augmenting Switching Regulators for Real-Time Monitoring Prabal Dutta of Technology Berkeley, CA 94720 Cambridge, MA 02139 Abstract We present iCount, a new energy meter design. For many systems that have a built-in switching regulator, adding a single wire between the regulator

  16. An AWGR based Low-Latency Optical Switch for Data Centers and High Performance Computing Systems

    E-Print Network [OSTI]

    Kolner, Brian H.

    i An AWGR based Low-Latency Optical Switch for Data Centers and High Performance Computing Systems based optical switch for data centers and high performance computing systems that builds upon several for Data Centers and High Performance Computing Systems ..i ABSTRACT .....................................

  17. 12003 Workshop on High Performance Switching and Routing M.Atiquzzaman, Univ. of Oklahoma, June 2003.

    E-Print Network [OSTI]

    Atiquzzaman, Mohammed

    12003 Workshop on High Performance Switching and Routing M.Atiquzzaman, Univ. of Oklahoma, June Fu) School of Computer Science University of Oklahoma, Norman, OK 73019-6151. Email: atiq@ou.edu #12;22003 Workshop on High Performance Switching and Routing M.Atiquzzaman, Univ. of Oklahoma, June 2003

  18. Implications of a Regime-Switching Model on Natural Gas Storage Valuation and Optimal Operation

    E-Print Network [OSTI]

    Forsyth, Peter A.

    Implications of a Regime-Switching Model on Natural Gas Storage Valuation and Optimal Operation-switching model for the risk adjusted natural gas spot price and study the implications of the model on the valuation and optimal operation of natural gas storage facilities. We calibrate the model parameters to both

  19. Polarity Switching and Transient Responses in Single Nanotube Nanofluidic Transistors Rohit Karnik,2

    E-Print Network [OSTI]

    Yang, Peidong

    Polarity Switching and Transient Responses in Single Nanotube Nanofluidic Transistors Rong Fan,1, can switch the nanofluidic transistors from p-type to ambipolar and n-type field effect transistors. Nanofluidic FETs have potential implications in subfemtoliter analytical technology and large

  20. Uniform Stability of Switched Linear Systems: Extensions of LaSalle's Invariance Principle

    E-Print Network [OSTI]

    Liebling, Michael

    1 Uniform Stability of Switched Linear Systems: Extensions of LaSalle's Invariance Principle Jo linear systems, where uniformity refers to the con- vergence rate of the multiple solutions that one be viewed as extensions of LaSalle's Invariance Principle to certain classes of switched linear systems

  1. Online Center of Gravity Estimation in Automotive Vehicles using Multiple Models and Switching

    E-Print Network [OSTI]

    Duffy, Ken

    Online Center of Gravity Estimation in Automotive Vehicles using Multiple Models and Switching and switching for realtime estimation of center of gravity (CG) position in automotive vehicles. The method utilizes simple linear vehicle models and assumes availability of standard stock automotive sensors. We

  2. Scheduling in Switches with Small Internal Buffers Nikos Chrysos and Manolis Katevenis

    E-Print Network [OSTI]

    Katevenis, Manolis G.H.

    . INTRODUCTION Packet networks require low-cost and fast packet switches to keep pace with the increase of today belong to the former category, but the trend is towards buffered fabrics that exploit advances://archvlsi.ics.forth.gr/bpbenes/ Draft version of 22 July 2005 Abstract-- Unbuffered crossbars or switching fabrics contain no internal

  3. Risk-sensitive optimal switching and applications to district energy systems

    E-Print Network [OSTI]

    Glendinning, Paul

    Risk-sensitive optimal switching and applications to district energy systems Jhonny Gonzalez School. Cost optimisation of energy system assets has typically been carried out under the assumption of risk-sensitive control, storage, risk measures, op- timal switching, district energy systems. I. INTRODUCTION The optimal

  4. Passivity Index for Switched System Technical Report of the ISIS Group

    E-Print Network [OSTI]

    Antsaklis, Panos

    Passivity Index for Switched System Design Technical Report of the ISIS Group at the University of Notre Dame ISIS-09-002 May, 2009 Michael J. McCourt and Panos J. Antsaklis Department of Electrical.J. McCourt and P.J. Antsaklis, "Passivity Index for Switched System Design," ISIS Technical Report

  5. A Converse Lyapunov Theorem for Uncertain Switched Linear Systems Hai Lin and Panos J. Antsaklis

    E-Print Network [OSTI]

    Antsaklis, Panos

    A Converse Lyapunov Theorem for Uncertain Switched Linear Systems Hai Lin and Panos J. Antsaklis Abstract-- The main contribution of this paper is a converse Lyapunov theorem derived for a class switching laws implies the existence of a polyhedral Lyapunov function along with conic partition based

  6. Energy landscape and thermally activated switching of submicron-sized ferromagnetic elements

    E-Print Network [OSTI]

    Van Den Eijnden, Eric

    Energy landscape and thermally activated switching of submicron-sized ferromagnetic elements Weinan September 2002; accepted 18 November 2002 Thermally activated switching and the energy landscape films. The energy landscape of such a system is nicely summarized on the plane spanned by the average

  7. On the concept of switching nonlinearity (a comment on "Switching control of linear systems for generating chaos" by X. Liu, K-L. Teo, H. Zhang and G. Chen)

    E-Print Network [OSTI]

    Emanuel Gluskin

    2008-03-22T23:59:59.000Z

    It is explained and stressed that the chaotic states in [1] are obtained by means of nonlinear switching.

  8. Fast deterministic switching in orthogonal spin torque devices via the control of the relative spin polarizations

    SciTech Connect (OSTI)

    Park, Junbo; Buhrman, R. A. [Cornell University, Ithaca, New York 14853 (United States)] [Cornell University, Ithaca, New York 14853 (United States); Ralph, D. C. [Cornell University, Ithaca, New York 14853 (United States) [Cornell University, Ithaca, New York 14853 (United States); Kavli Institute at Cornell, Ithaca, New York 14853 (United States)

    2013-12-16T23:59:59.000Z

    We model 100 ps pulse switching dynamics of orthogonal spin transfer (OST) devices that employ an out-of-plane polarizer and an in-plane polarizer. Simulation results indicate that increasing the spin polarization ratio, C{sub P}?=?P{sub IPP}/P{sub OPP}, results in deterministic switching of the free layer without over-rotation (360 rotation). By using spin torque asymmetry to realize an enhanced effective P{sub IPP}, we experimentally demonstrate this behavior in OST devices in parallel to anti-parallel switching. Modeling predicts that decreasing the effective demagnetization field can substantially reduce the minimum C{sub P} required to attain deterministic switching, while retaining low critical switching current, I{sub p}???500??A.

  9. On the mechanism of NO selective catalytic reduction by hydrocarbons over Cu-ZSM-5 via X-ray absorption spectroscopic study

    SciTech Connect (OSTI)

    Liu, D.J. [AlliedSignal Inc., Des Plaines, IL (United States)] [AlliedSignal Inc., Des Plaines, IL (United States); Robota, H.J. [ASEC, Tulsa, OK (United States)] [ASEC, Tulsa, OK (United States)

    1999-04-08T23:59:59.000Z

    An understanding of the catalytic mechanism of NO{sub x} reduction is critical for the development of next-generation high-fuel efficiency, low-emission vehicles. This paper compiles the investigations in recent years on the mechanism of NO selective catalytic reduction (SCR) by hydrocarbon over Cu-ZSM-5. The studies were focused on the oxidation state and coordination chemistry of the exchanged Cu as the active site during the catalytic reaction using X-ray absorption spectroscopic (XAS) techniques, mainly XANES and EXAFS. Their experiment demonstrated the existence of a redox mechanism which involves cyclic switching of the oxidation states between Cu(II) and Cu(I) in an oxygen-rich gas mixture under elevated temperature. The authors also observed the coordination structural change of copper ion in ZSM-5 accompanying the change of oxidation state. A correlation between cuprous ion concentration and catalytic activity was found in NO SCR by propene. The impact of another two hydrocarbons, propane and methane, on the copper redox behavior also appears to correlate to catalytic activities in the respective mixtures. Discussions on the nature of the active sites and the mechanism of SCR are presented based on the XAS data analysis. The similarity and difference of the physical properties of copper ion between NO catalytic decomposition and NO SCR are also discussed.

  10. Positive feedback and temperature mediated molecular switch controls differential gene regulation in Bordetella pertussis

    E-Print Network [OSTI]

    Arnab Bandyopadhyay; Suman K. Banik

    2012-08-17T23:59:59.000Z

    Based on the phosphorelay kinetics operative within BvgAS two component system we propose a mathematical framework for signal transduction and gene regulation of phenotypic phases in Bordetella pertussis. The proposed model identifies a novel mechanism of transcriptional interference between two promoters present in the bvg locus. To understand the system behavior under elevated temperature, the developed model has been studied in two different ways. First, a quasi-steady state analysis has been carried out for the two component system, comprising of sensor BvgS and response regulator BvgA. The quasi-steady state analysis reveals temperature induced sharp molecular switch, leading to amplification in the output of BvgA. Accumulation of a large pool of BvgA thus results into differential regulation of the downstream genes, including the gene encoding toxin. Numerical integration of the full network kinetics is then carried out to explore time dependent behavior of different system components, that qualitatively capture the essential features of experimental results performed in vivo. Furthermore, the developed model has been utilized to study mutants that are impaired in their ability to phosphorylate the transcription factor, BvgA, of the signaling network.

  11. Proposal for the award of a blanket purchase contract for the supply and maintenance of high-performance Ethernet switches

    E-Print Network [OSTI]

    2014-01-01T23:59:59.000Z

    Proposal for the award of a blanket purchase contract for the supply and maintenance of high-performance Ethernet switches

  12. 130kV 130A High Voltage Switching Mode Power Supply for Neutral Injections Control Issues and Algorithms

    E-Print Network [OSTI]

    130kV 130A High Voltage Switching Mode Power Supply for Neutral Injections Control Issues and Algorithms

  13. Micro-electro-mechanically switchable near infrared complementary metamaterial absorber

    SciTech Connect (OSTI)

    Pitchappa, Prakash; Pei Ho, Chong [Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 (Singapore); Institute of Microelectronics (IME), 11 Science Park Road, Singapore 117685 (Singapore); Kropelnicki, Piotr; Singh, Navab; Kwong, Dim-Lee [Institute of Microelectronics (IME), 11 Science Park Road, Singapore 117685 (Singapore); Lee, Chengkuo, E-mail: elelc@nus.edu.sg [Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 (Singapore)

    2014-05-19T23:59:59.000Z

    We experimentally demonstrate a micro-electro-mechanically switchable near infrared complementary metamaterial absorber by integrating the metamaterial layer to be the out of plane movable microactuator. The metamaterial layer is electrostatically actuated by applying voltage across the suspended complementary metamaterial layer and the stationary bottom metallic reflector. Thus, the effective spacing between the metamaterial layer and bottom metal reflector is varied as a function of applied voltage. With the reduction of effective spacing between the metamaterial and reflector layers, a strong spectral blue shift in the peak absorption wavelength can be achieved. With spacing change of 300?nm, the spectral shift of 0.7??m in peak absorption wavelength was obtained for near infrared spectral region. The electro-optic switching performance of the device was characterized, and a striking switching contrast of 1500% was achieved at 2.1??m. The reported micro-electro-mechanically tunable complementary metamaterial absorber device can potentially enable a wide range of high performance electro-optical devices, such as continuously tunable filters, modulators, and electro-optic switches that form the key components to facilitate future photonic circuit applications.

  14. BULKING SLUDGE TREATMENT BY MICROSCOPIC OBSERVATION AND MECHANICAL TREATMENT

    E-Print Network [OSTI]

    for the operation of the biological stage of waste water treatment plants. If the threatening extensive growth of wastewater treatment plants often need a complex control for the optimal processing. The measurement status and for the regulation of biological parts in waste water treatment plants. Furthermore, e

  15. Switched system modeling and robust steering control of the tail end phase in a hot strip mill

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    Switched system modeling and robust steering control of the tail end phase in a hot strip mill Ivan`eres-l`es-Metz Cedex, France Abstract In this article, a robust steering control for the last phase of the rolling switched system. The switchings make the system unstable and the task of the tail end steering control

  16. CreditFlowControlled ATM over HIC Links in the ASICCOM ``ATLAS I'' SingleChip Switch

    E-Print Network [OSTI]

    Katevenis, Manolis G.H.

    flow control. 1. Introduction Switches are the building blocks for highspeed networks in which high adopted as the main high speed technology in both wide and local area networks. ATM has been architectedLAne Switch I): a generalpurpose, singlechip gigabit ATM switch, with creditbased flow control, multiple

  17. SWITCHING METHODS FOR LINEAR TURBO EQUALIZATION Seok-Jun Lee, Naresh R. Shanbhag, and Andrew C. Singer

    E-Print Network [OSTI]

    Singer, Andrew C

    SWITCHING METHODS FOR LINEAR TURBO EQUALIZATION Seok-Jun Lee, Naresh R. Shanbhag, and Andrew C,acsinger]@uiuc.edu ABSTRACT In this paper, several switching methods are presented for a class of switching turbo equalization the best bit error rate (1.5dB processing gain at 10-4 ) with low complexity. 1. INTRODUCTION The turbo

  18. Phase space quantum mechanics - Direct

    SciTech Connect (OSTI)

    Nasiri, S.; Sobouti, Y.; Taati, F. [Institute for Advanced Studies in Basic Sciences, Zanjan, 45195-1159 (Iran, Islamic Republic of) and Department of Physics, Zanjan University, Zanjan (Iran); Institute for Advanced Studies in Basic Sciences, Zanjan, 45195-1159 (Iran, Islamic Republic of); Institute for Advanced Studies in Basic Sciences, Zanjan, 45195-1159 (Iran, Islamic Republic of) and Department of Physics, University of Kurdistan, D-78457 Sanadaj (Iran)

    2006-09-15T23:59:59.000Z

    Conventional approach to quantum mechanics in phase space (q,p), is to take the operator based quantum mechanics of Schroedinger, or an equivalent, and assign a c-number function in phase space to it. We propose to begin with a higher level of abstraction, in which the independence and the symmetric role of q and p is maintained throughout, and at once arrive at phase space state functions. Upon reduction to the q- or p-space the proposed formalism gives the conventional quantum mechanics, however, with a definite rule for ordering of factors of noncommuting observables. Further conceptual and practical merits of the formalism are demonstrated throughout the text.

  19. Possible temperature control DC switch effect between two superconductors

    E-Print Network [OSTI]

    Tian De Cao

    2011-08-11T23:59:59.000Z

    The lifetime of an electron pair could not be unlimited long, on the basis of this, we suggest a model. The model means that the movements of charge carriers in a superconductor should have three forms: the single-electron movement, the single-pair movement, and the revolving around the mass center of two electrons in a pair. Thus the current in a superconductor has three possible parts. Similarly, there should be three possible effects in a SIS junction: the tunneling of single electron, the tunneling of single pair, and the pair-forming following the pair-breaking. This paper will discuss these problems and present a possible temperature control DC switch effect between two superconductors.

  20. Spin switches for compact implementation of neuron and synapse

    SciTech Connect (OSTI)

    Quang Diep, Vinh, E-mail: vdiep@purdue.edu; Sutton, Brian; Datta, Supriyo [School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Behin-Aein, Behtash [GLOBALFOUNDRIES, Inc., Sunnyvale, California 94085 (United States)

    2014-06-02T23:59:59.000Z

    Nanomagnets driven by spin currents provide a natural implementation for a neuron and a synapse: currents allow convenient summation of multiple inputs, while the magnet provides the threshold function. The objective of this paper is to explore the possibility of a hardware neural network implementation using a spin switch (SS) as its basic building block. SS is a recently proposed device based on established technology with a transistor-like gain and input-output isolation. This allows neural networks to be constructed with purely passive interconnections without intervening clocks or amplifiers. The weights for the neural network are conveniently adjusted through analog voltages that can be stored in a non-volatile manner in an underlying CMOS layer using a floating gate low dropout voltage regulator. The operation of a multi-layer SS neural network designed for character recognition is demonstrated using a standard simulation model based on coupled Landau-Lifshitz-Gilbert equations, one for each magnet in the network.

  1. 275 C Downhole Switched-Mode Power Supply

    SciTech Connect (OSTI)

    Chris Hutchens; Vijay Madhuravasal

    2008-08-31T23:59:59.000Z

    A vee-square (V2) control based controller IC is developed for a switch mode power supply capable of operating at extreme temperature/harsh environment conditions. A buck type regulator with silicon carbide power junction field effect transistors (JFET) as power devices is used to analyze the performance of controller. Special emphases are made on the analog sub-blocks--voltage reference, operational transconductance amplifier and comparator as individual building blocks. Transformer coupled gate drives and high temperature operable magnetic cores and capacitors are identified and tested for use in the design. Conventional ceramic chip packaging of ICs combined with lead carrier type mounting of passive filter components is introduced for hybrid packaging of the complete product. The developed SMPS is anticipated to support the operation of down-hole microcontrollers and other electronics devices that require low/medium power filtered dc inputs over an operating temperature of 275 C.

  2. Air-Gap Convection in a Switched Reluctance Machine

    E-Print Network [OSTI]

    Romanazzi, Pietro

    2015-01-01T23:59:59.000Z

    Switched reluctance machines (SRMs) have recently become popular in the automotive market as they are a good alternative to the permanent magnet machines commonly employed for an electric powertrain. Lumped parameter thermal networks are usually used for thermal analysis of motors due to their low computational cost and relatively accurate results. A critical aspect to be modelled is the rotor-stator air-gap heat transfer, and this is particularly challenging in an SRM due to the salient pole geometry. This work presents firstly a review of the literature including the most relevant correlations for this geometry, and secondly, numerical CFD simulations of air-gap heat transfer for a typical configuration. A new correlation has been derived: $\\mathbf{Nu=0.181\\ Ta_m^{0.207}}$

  3. High gain photoconductive semiconductor switch having tailored doping profile zones

    DOE Patents [OSTI]

    Baca, Albert G. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Mar, Alan (Albuquerque, NM); Zutavern, Fred J (Albuquerque, NM); Hjalmarson, Harold P. (Albuquerque, NM); Allerman, Andrew A. (Albuquerque, NM); Zipperian, Thomas E. (Edgewood, NM); O'Malley, Martin W. (Edgewood, NM); Helgeson, Wesley D. (Albuquerque, NM); Denison, Gary J. (Sandia Park, NM); Brown, Darwin J. (Albuquerque, NM); Sullivan, Charles T. (Albuquerque, NM); Hou, Hong Q. (Albuquerque, NM)

    2001-01-01T23:59:59.000Z

    A photoconductive semiconductor switch with tailored doping profile zones beneath and extending laterally from the electrical contacts to the device. The zones are of sufficient depth and lateral extent to isolate the contacts from damage caused by the high current filaments that are created in the device when it is turned on. The zones may be formed by etching depressions into the substrate, then conducting epitaxial regrowth in the depressions with material of the desired doping profile. They may be formed by surface epitaxy. They may also be formed by deep diffusion processes. The zones act to reduce the energy density at the contacts by suppressing collective impact ionization and formation of filaments near the contact and by reducing current intensity at the contact through enhanced current spreading within the zones.

  4. Effect of electronic reconstruction on cuprate-manganite spin switches.

    SciTech Connect (OSTI)

    Liu, Y.; Visani, C.; Nemes, N. M.; Fitzsimmons, M. R.; Zhu, L. Y.; Tornos, J.; Zhernenkov, M.; Hoffmann, A.; Leon, C.; Santamaria, J.; te Velthuis, S. G. E. (Materials Science Division); (Universidad Complutense de Madrid); (LANL)

    2012-01-01T23:59:59.000Z

    We examine the anomalous inverse spin switch behavior in La{sub 0.7}Ca{sub 0.3}MnO{sub 3}(LCMO)/YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (YBCO)/LCMO trilayers by combined transport studies and polarized neutron reflectometry. Measuring magnetization profiles and magnetoresistance in an in-plane rotating magnetic field, we prove that, contrary to many accepted theoretical scenarios, the relative orientation between the two LCMO's magnetizations is not sufficient to determine the magnetoresistance. Rather the field dependence of magnetoresistance is explained by the interplay between the applied magnetic field and the (exponential tail of the) induced exchange field in YBCO, the latter originating from the electronic reconstruction at the LCMO/YBCO interfaces.

  5. E-beam high voltage switching power supply

    DOE Patents [OSTI]

    Shimer, D.W.; Lange, A.C.

    1996-10-15T23:59:59.000Z

    A high-power power supply produces a controllable, constant high voltage output under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules. 5 figs.

  6. E-beam high voltage switching power supply

    DOE Patents [OSTI]

    Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

    1996-01-01T23:59:59.000Z

    A high-power power supply produces a controllable, constant high voltage put under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules.

  7. Efficiency of stripping mechanisms

    E-Print Network [OSTI]

    F. Combes

    2003-08-18T23:59:59.000Z

    There are several physical processes to remove gas from galaxies in clusters, with subsequent starvation and star formation quenching: tidal interactions between galaxies, or tidal stripping from the cluster potential itself, interactions with the hot intra-cluster medium (ICM) through ram pressure, turbulent or viscous stripping, or also outflows from star formation of nuclear activity, We review the observational evidence for all processes, and numerical simulations of galaxies in clusters which support the respective mechanisms. This allows to compare their relative efficiencies, all along cluster formation.

  8. Size dependence of magnetization switching and its dispersion of Co/Pt nanodots under the assistance of radio frequency fields

    SciTech Connect (OSTI)

    Furuta, Masaki, E-mail: furutam@mail.tagen.tohoku.ac.jp; Okamoto, Satoshi; Kikuchi, Nobuaki; Kitakami, Osamu [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan); Shimatsu, Takehito [Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai 980-8578 (Japan); Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577 (Japan)

    2014-04-07T23:59:59.000Z

    We have studied the dot size dependence of microwave assisted magnetization switching (MAS) on perpendicular magnetic Co/Pt multilayer dot array. The significant microwave assistance effect has been observed over the entire dot size D ranging from 50?nm to 330?nm examined in the present study. The MAS behavior, however, critically depends on D. The excitation frequency dependence of the switching field is well consistent with the spin wave theory, indicating that the magnetization precession in MAS is in accordance with the well defined eigenmodes depending on the dot diameter. The lowest order spin wave is only excited for D???100?nm, and then the MAS effect is well consistent with that of the single macrospin prediction. On the other hand, higher order spin waves are excited for D?>?100?nm, giving rise to the significant enhancement of the MAS effect. The dispersion of MAS effect also depends on D and is significantly reduced for the region of D?>?100?nm. This significant reduction of the dispersion is attributed to the essential feature of the MAS effect which is insensitive to the local fluctuation of anisotropy field, such as defect, damaged layer, and so on.

  9. Ionic field effect and memristive phenomena in single-point ferroelectric domain switching

    SciTech Connect (OSTI)

    Ievlev, Anton [ORNL] [ORNL; Morozovska, A. N. [National Academy of Science of Ukraine, Kiev, Ukraine] [National Academy of Science of Ukraine, Kiev, Ukraine; Eliseev, E. A. [National Academy of Science of Ukraine, Kiev, Ukraine] [National Academy of Science of Ukraine, Kiev, Ukraine; Shur, Vladimir Ya. [Ural Federal University, Russia] [Ural Federal University, Russia; Kalinin, Sergei V [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    Electric field induced polarization switching underpins most functional applications of ferroelectric materials in information technology, materials science, and optoelectronics. In the last 20 years, much attention has been focused on the switching of individual domains using scanning probe microscopy, both as model of ferroelectric data storage and approach to explore fundamental physics of ferroelectric switching. The classical picture of tip induced switching includes formation of cylindrical domain oriented along the tip field, with the domain size is largely determined by the tip-induced field distribution and domain wall motion kinetics. The polarization screening is recognized as a necessary precondition to the stability of ferroelectric phase; however, screening processes are generally considered to be uniformly efficient and not leading to changes in switching behavior. Here, we demonstrate that single-point tip-induced polarization switching can give rise to a surprisingly broad range of domain morphologies, including radial and angular instabilities. These behaviors are traced to the surface screening charge dynamics, which in some cases can even give rise to anomalous switching against the electric field (ionic field effect). The implications of these behaviors for ferroelectric materials and devices are discussed.

  10. Effects of graphene on electro-optic switching and spontaneous polarization of a ferroelectric liquid crystal

    SciTech Connect (OSTI)

    Basu, Rajratan, E-mail: basu@usna.edu [Department of Physics, Soft-matter and Nanomaterials Laboratory, The United States Naval Academy, Annapolis, Maryland 21402 (United States)

    2014-09-15T23:59:59.000Z

    A small quantity of graphene flakes was doped in a ferroelectric liquid crystal (FLC), and the field-induced ferroelectric electro-optic switching was found to be significantly faster in the FLC + graphene hybrid than that of the pure FLC. Further studies revealed that the suspended graphene flakes enhanced the FLC's spontaneous polarization by improving smectic-C ordering resulting from the ?? electron stacking, and reduced rotation viscosity by trapping some of the free ions of the FLC media. These effects coherently impacted the FLC-switching phenomenon, enabling the FLC molecules to switch faster on reversing an external electric field.

  11. Three-terminal resistive switching memory in a transparent vertical-configuration device

    SciTech Connect (OSTI)

    Ungureanu, Mariana; Llopis, Roger [CIC nanoGUNE Consolider, Donostia - San Sebastian (Spain)] [CIC nanoGUNE Consolider, Donostia - San Sebastian (Spain); Casanova, Flix; Hueso, Luis E. [CIC nanoGUNE Consolider, Donostia - San Sebastian (Spain) [CIC nanoGUNE Consolider, Donostia - San Sebastian (Spain); Ikerbasque, Basque Foundation for Science, Bilbao (Spain)

    2014-01-06T23:59:59.000Z

    The resistive switching phenomenon has attracted much attention recently for memory applications. It describes the reversible change in the resistance of a dielectric between two non-volatile states by the application of electrical pulses. Typical resistive switching memories are two-terminal devices formed by an oxide layer placed between two metal electrodes. Here, we report on the fabrication and operation of a three-terminal resistive switching memory that works as a reconfigurable logic component and offers an increased logic density on chip. The three-terminal memory device we present is transparent and could be further incorporated in transparent computing electronic technologies.

  12. Differential ultrafast all-optical switching of the resonances of a micropillar cavity

    SciTech Connect (OSTI)

    Thyrrestrup, Henri, E-mail: h.t.nielsen@utwente.nl; Yce, Emre; Ctistis, Georgios; Vos, Willem L. [Complex Photonic Systems (COPS), MESA Institute for Nanotechnology, University of Twente, 7500 AE Enschede (Netherlands); Claudon, Julien; Grard, Jean-Michel, E-mail: jean-michel.gerard@cea.fr [University Grenoble Alpes, INAC-SP2M, Nanophysics and Semiconductors Lab, F-38000 Grenoble (France); CEA, INAC-SP2M, Nanophysics and Semiconductors Lab, F-38000 Grenoble (France)

    2014-09-15T23:59:59.000Z

    We perform frequency- and time-resolved all-optical switching of a GaAs-AlAs micropillar cavity using an ultrafast pump-probe setup. The switching is achieved by two-photon excitation of free carriers. We track the cavity resonances in time with a high frequency resolution. The pillar modes exhibit simultaneous frequency shifts, albeit with markedly different maximum switching amplitudes and relaxation dynamics. These differences stem from the non-uniformity of the free carrier density in the micropillar, and are well understood by taking into account the spatial distribution of injected free carriers, their spatial diffusion and surface recombination at micropillar sidewalls.

  13. Dual-mode ion switching conducting polymer films as high energy supercapacitor materials

    SciTech Connect (OSTI)

    Naoi, Katsuhiko; Oura, Yasushi [Tokyo Univ. of Agriculture and Technology, Koganei, Tokyo (Japan). Dept. of Applied Chemistry

    1995-12-31T23:59:59.000Z

    The electropolymerized polypyrrole films formed from micellar solution of anionic surfactants, viz., Dodecylbenzene sulfonate (DBS), showed potential-dependent anion and cation ion switching behavior and the peculiar columnar structure. The formation process and the redox of the polypyrrole was studied with the in situ atomic force microscopy (AFM) and electrochemical quartz crystal microbalance (EQCM) methods. In-situ AFM observation clearly indicated that such a columnar structure started to form around critical charge densities of 60--100 mC cm{sup {minus}2}. The cyclic voltammogram for the PPy doped with DBS{sup {minus}} film showed two redox couples, each of which corresponds to a cation and an anion exchange process. Thus, the film behaves as a dual-mode ion doping/undoping exchanger. As the PPy film was prepared in higher concentration of the surfactant dopant, where the micelles are formed in solution, the resulting film showed a considerably higher (ca. three orders of magnitude) diffusion coefficient compared to ordinary PPy films so far reported. Such an enhanced diffusivity of ions could be attributed to a peculiar structure of the polymer formed. The feasibility of such polypyrrole in use of supercapacitor material was discussed.

  14. IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS, VOL. 12, NO. 5, SEPTEMBER/OCTOBER 2006 997 4 4 Nonblocking Polymeric Thermo-Optic Switch

    E-Print Network [OSTI]

    Chen, Ray

    4 4 Nonblocking Polymeric Thermo-Optic Switch Matrix Using the Total Internal Reflection Effect nonblocking thermo-optic switch matrix that uses the total internal reflection effect, is designed, switch ma- trix, thermo-optic effect. I. INTRODUCTION OPTICAL switches using total internal reflection

  15. Paper presented at Bulk Power Systems Dynamics and Control IV -Restructuring, August 24-28, Santorini, Greece "The Dynamics of Customers Switching

    E-Print Network [OSTI]

    -28, Santorini, Greece "The Dynamics of Customers Switching Suppliers in Deregulated Power Markets" Richard E

  16. Anomalous reduction of the switching voltage of Bi-doped Ge{sub 0.5}Se{sub 0.5} ovonic threshold switching devices

    SciTech Connect (OSTI)

    Seo, Juhee [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Nanomaterials Science and Engineering, University of Science and Technology, Daejeon 305-350 (Korea, Republic of); Ahn, Hyung-Woo [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Material Science and Engineering, Korea University, Seoul 136-701 (Korea, Republic of); Shin, Sang-yeol [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of); Department of Materials Science and Engineering, Korea Aerospace University, Goyang 412-791 (Korea, Republic of); Cheong, Byung-ki; Lee, Suyoun, E-mail: slee-eels@kist.re.kr [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791 (Korea, Republic of)

    2014-04-14T23:59:59.000Z

    Switching devices based on Ovonic Threshold Switching (OTS) have been considered as a solution to overcoming limitations of Si-based electronic devices, but the reduction of switching voltage is a major challenge. Here, we investigated the effect of Bi-doping in Ge{sub 0.5}Se{sub 0.5} thin films on their thermal, optical, electrical properties, as well as on the characteristics of OTS devices. As Bi increased, it was found that both of the optical energy gap (E{sub g}{sup opt}) and the depth of trap states decreased resulting in a drastic reduction of the threshold voltage (V{sub th}) by over 50%. In addition, E{sub g}{sup opt} was found to be about three times of the conduction activation energy for each composition. These results are explained in terms of the Mott delocalization effect by doping Bi.

  17. Resistive switching and conductance quantization in Ag/SiO{sub 2}/indium tin oxide resistive memories

    SciTech Connect (OSTI)

    Gao, S.; Chen, C.; Liu, H. Y.; Lin, Y. S.; Li, S. Z.; Lu, S. H.; Wang, G. Y.; Song, C.; Zeng, F., E-mail: zengfei@mail.tsinghua.edu.cn; Pan, F., E-mail: panf@mail.tsinghua.edu.cn [Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Zhai, Z. [Department of Metallurgical Engineering, College of Materials Science and Engineering, Taiyuan University of Technology, Taiyuan 030024 (China)

    2014-08-11T23:59:59.000Z

    The Ag/SiO{sub 2}/indium tin oxide (ITO) devices exhibit bipolar resistive switching with a large memory window of ?10{sup 2}, satisfactory endurance of >500 cycles, good retention property of >2000?s, and fast operation speed of <100?ns, thus being a type of promising resistive memory. Under slow voltage sweep measurements, conductance plateaus with a conductance value of integer or half-integer multiples of single atomic point contact have been observed, which agree well with the physical phenomenon of conductance quantization. More importantly, the Ag/SiO{sub 2}/ITO devices exhibit more distinct quantized conductance plateaus under pulse measurements, thereby showing the potential for realizing ultra-high storage density.

  18. Role of oxygen vacancies in resistive switching in Pt/Nb-doped SrTiO{sub 3}

    SciTech Connect (OSTI)

    Park, Jinho; Kwon, Deok-Hwang; Park, Hongwoo; Kim, M., E-mail: mkim@snu.ac.kr [Research Institute of Advanced Materials, Department of Material Science and Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Jung, C. U. [Department of Physics, Hankuk University of Foreign Studies, Yongin, Kyungki 449-791 (Korea, Republic of)

    2014-11-03T23:59:59.000Z

    Oxygen vacancies at the metal/oxide interface, driven by an electric field, have been considered responsible for the switching to the low-resistance state. We studied the electrical properties, along with microscopic observations, of the Pt/Nb-doped SrTiO{sub 3} (001) single-crystal system. Electron energy loss spectroscopy revealed highly accumulated oxygen vacancies at the interface in the high-resistance state, contrasting to common explanation. Higher resistance state by more oxygen vacancies was further confirmed in Pt/H{sub 2}-annealed SrTiO{sub 3}. These results suggest the presence of an interfacial state which dominantly determined the resistivity by changing the barrier height at the interface.

  19. Magnetic switching behaviors of orbital states with different magnetic quantum numbers in Au/Fe/MgO multilayer system

    SciTech Connect (OSTI)

    Suzuki, Kosuke, E-mail: kosuzuki@gunma-u.ac.jp; Takubo, Shota; Kato, Tadashi; Yamazoe, Masatoshi; Hoshi, Kazushi; Sakurai, Hiroshi [Department of Electronics and Informatics, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Homma, Yoshiya [International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, 2145-2 Narita-cho, Oarai-machi, Higashiibaraki-gun, Ibaraki 311-1313 (Japan); Itou, Masayoshi; Sakurai, Yoshiharu [Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)

    2014-08-18T23:59:59.000Z

    A spin specific magnetic hysteresis (SSMH) curve and an orbital specific magnetic hysteresis (OSMH) curve are obtained for Fe/Au/Fe/MgO multilayers by magnetic Compton scattering and SQUID magnetometer measurements. The SSMH curve with each contribution of magnetic quantum number |m|?=?0, 1, and 2 states is obtained by decomposition analyses of magnetic Compton profiles. Residual magnetization is observed for the SSMH curve with magnetic quantum number |m|?=?0, 2 and the OSMH curve. Although the SQUID magnetometer measurements do not show perpendicular magnetic anisotropy (PMA) in the present Fe/Au/Fe/MgO multilayer film, the SSMH curve with magnetic quantum number |m|?=?0, 2 and OSMH curve show switching behaviors of PMA.

  20. Integrated switch for simultaneous mode-division multiplexing (MDM) and wavelength-division multiplexing (WDM)

    E-Print Network [OSTI]

    Stern, Brian; Chen, Christine P; Tzuang, Lawrence D; Cardenas, Jaime; Bergman, Keren; Lipson, Michal

    2015-01-01T23:59:59.000Z

    Leveraging the spatial modes of multimode waveguides using mode-division multiplexing (MDM) on an integrated photonic chip allows unprecedented scaling of bandwidth density for on-chip communication. Switching channels between waveguides is critical for future scalable optical networks, but its implementation in multimode waveguides must address how to simultaneously control modes with vastly different optical properties. Here we present a platform for switching signals between multimode waveguides based on individually processing the spatial mode channels using single-mode elements. Using this wavelength-division multiplexing (WDM) compatible platform, we demonstrate a 1x2 multimode switch for a silicon chip which routes four data channels with low (power penalties below 1.4 dB on all channels while routing 10 Gbps data when each channel is input and routed separately. The switch exhibits an additional power penalty of less than 2.4 dB when all f...

  1. Estimation of linear autoregressive models with Markov-switching, the E.M. algorithm revisited

    E-Print Network [OSTI]

    Rynkiewicz, Joseph

    2008-01-01T23:59:59.000Z

    This work concerns estimation of linear autoregressive models with Markov-switching using expectation maximisation (E.M.) algorithm. Our method generalise the method introduced by Elliot for general hidden Markov models and avoid to use backward recursion.

  2. An on-line performance optimization of the Switched Reluctance Motor

    E-Print Network [OSTI]

    Tandon, Piyush

    1996-01-01T23:59:59.000Z

    The Switched Reluctance Motor (SRM) has been developed extensively during the past 15 years. Due to the simple motor construction and power converter requirements, SRM drives have been found competitive with traditional ...

  3. Electro-optic harmonic conversion to switch a laser beam out of a cavity

    DOE Patents [OSTI]

    Haas, R.A.; Henesian, M.A.

    1984-10-19T23:59:59.000Z

    The present invention relates to switching laser beams out of laser cavities, and more particularly, it relates to the use of generating harmonics of the laser beam to accomplish the switching. When laser light is generatd in a laser cavity the problem arises of how to switch the laser light out of the cavity in order to make use of the resulting laser beam in a well known multitude of ways. These uses include range finding, communication, remote sensing, medical surgery, laser fusion applications and many more. The switch-out problem becomes more difficult as the size of the laser aperture grows such as in laser fusion applications. The final amplifier stages of the Nova and Novette lasers at Lawrence Livermore National Laboratory are 46 centimeters with the laser beam expanded to 74 centimeters thereafter. Larger aperture lasers are planned.

  4. On the NP-hardness of checking matrix polytope stability and continuous-time switching stability

    E-Print Network [OSTI]

    Gurvits, Leonid

    Motivated by questions in robust control and switched linear dynamical systems, we consider the problem checking whether all convex combinations of k matrices in R[superscript ntimesn] are stable. In particular, we are ...

  5. A Low Hysteresis NiTiFe Shape Memory Alloy Based Thermal Conduction Switch

    SciTech Connect (OSTI)

    Lemanski, J. L.; Krishnan, V. B.; Manjeri, R. Mahadevan; Vaidyanathan, R. [University of Central Florida, Orlando, Florida, 32816 (United States); Notardonato, W. U. [National Aeronautics and Space Administration, Kennedy Space Center, Florida, 32899 (United States)

    2006-03-31T23:59:59.000Z

    Shape memory alloys possess the ability to return to a preset shape by undergoing a solid state phase transformation at a particular temperature. This work reports on the development and testing of a low temperature thermal conduction switch that incorporates a NiTiFe shape memory element for actuation. The switch was developed to provide a variable conductive pathway between liquid methane and liquid oxygen dewars in order to passively regulate the temperature of methane. The shape memory element in the switch undergoes a rhombohedral or R-phase transformation that is associated with a small hysteresis (typically 1-2 deg. C) and offers the advantage of precision control over a set temperature range. For the NiTiFe alloy used, its thermomechanical processing, subsequent characterization using dilatometry, differential scanning calorimetry and implementation in the conduction switch configuration are addressed.

  6. On the synthesis of switched output feedback controllers for linear, time-invariant systems

    E-Print Network [OSTI]

    Santarelli, Keith R. (Keith Robert), 1977-

    2007-01-01T23:59:59.000Z

    The theory of switching systems has seen many advances in the past decade. Its beginnings were founded primarily due to the physical limitations in devices to implement control such as relays, but today there exists a ...

  7. PRICING ASSET SCHEDULING FLEXIBILITY USING OPTIMAL SWITCHING RENE CARMONA AND MICHAEL LUDKOVSKI

    E-Print Network [OSTI]

    Ludkovski, Mike

    PRICING ASSET SCHEDULING FLEXIBILITY USING OPTIMAL SWITCHING REN´E CARMONA AND MICHAEL LUDKOVSKI Abstract. We study the financial engineering aspects of operational flexibility of energy assets methods. 1. Introduction. Pricing of operational flexibility is one of the fundamental problems

  8. Priority Based Switch Allocator in Adaptive Physical Channel Regulator for On Chip Interconnects

    E-Print Network [OSTI]

    Mahapatra, Sonali

    2014-08-04T23:59:59.000Z

    C) is an excellent architectural paradigm which offers a stable and generalized communication platform for large scale of chip multiprocessors. The existing model APCR has three regulation schemes designed at switch allocation stage of NoC router pipelining...

  9. Design and testing of a sensorless switched reluctance motor drive with a custom integrated circuit controller

    E-Print Network [OSTI]

    Zhang, Yingxia

    1996-01-01T23:59:59.000Z

    The switched reluctance motor (SRM) has become an attractive alternative candidate to conventional ae or dc motors for adjustable speed drive applications. The SRM drive system consists of a power converter and a control section. Making the control...

  10. A comparison of cue processing and executive functioning in child task-switching

    E-Print Network [OSTI]

    Holt, Anna E.

    2011-01-01T23:59:59.000Z

    Research, 29 (6), 597-626. Huizinga, M. , Dolan, C. V. , &Neuropsychologia, 44, 2017- Huizinga, M. , & van der Molen,on task-switch fluency (Huizinga & van der Molan, 2006).

  11. Demonstration of a hitless bypass switch using nanomechanical perturbation for high-bitrate transparent networks

    E-Print Network [OSTI]

    Chatterjee, Rohit

    We demonstrate an optical hitless bypass switch based on nanomechanical proximity perturbation for high-bitrate transparent networks. Embedded in a single-level ?-imbalanced Mach-Zehnder interferometer, the two ...

  12. Tunable Substrate Integrated Waveguide Filters Implemented with PIN Diodes and RF MEMS Switches

    E-Print Network [OSTI]

    Armendariz, Marcelino

    2012-02-14T23:59:59.000Z

    This thesis presents the first fully tunable substrate integrated waveguide (SIW) filter implemented with PIN diodes and RF MEMS switches. The methodology for tuning SIW filters is explained in detail and is used to create three separate designs...

  13. Tunable Substrate Integrated Waveguide Filters Implemented with PIN Diodes and RF MEMS Switches

    E-Print Network [OSTI]

    Armendariz, Marcelino

    2012-02-14T23:59:59.000Z

    This thesis presents the first fully tunable substrate integrated waveguide (SIW) filter implemented with PIN diodes and RF MEMS switches. The methodology for tuning SIW filters is explained in detail and is used to create three separate designs...

  14. Efficiency consideration of DC link soft-switching inverters for motor drive applications

    SciTech Connect (OSTI)

    Lai, J.S.; Young, R.W.; McKeever, J.W.

    1994-12-31T23:59:59.000Z

    This paper critically evaluates efficiency of soft switching inverters including an actively clamped resonant dc link inverter and a clamped-mode resonant pole inverter. An analytical approach to evaluating efficiency of the clamped-mode soft switching inverter has been developed. The evaluation results are compared with that of the standard pulse-width-modulation (PWM) inverter. A 50-kW induction motor is used as the variable load, and the inverter efficiency is evaluated under different speed and torque conditions. The clamped-mode soft-switching inverter, although eliminating the switching loss, shows poor efficiency over the entire load range. Under low load conditions, the efficiency profile is even worse. The actively clamped resonant dc link inverter shows highest efficiency over the entire speed and torque range. However, its energy saving over the standard PWM inverter is marginal under full load or high speed conditions.

  15. Design and Evaluation of a 42-V Automotive Alternator With Integrated Switched-Mode Rectifier

    E-Print Network [OSTI]

    Tang, Sai Chun

    This paper presents techniques for the design of high-power Lundell alternators with integrated switched-mode rectifiers. A multisection stator winding and interleaved rectifier arrangement is introduced that enables high ...

  16. IEEE TRANSACTIONS ON POWER ELECTRONICS 1 A Soft-Switched Hybrid-Modulation Scheme

    E-Print Network [OSTI]

    Mazumder, Sudip K.

    )/208-V (ac) HF inverter.21 Index Terms--Capacitor-less, high-frequency (HF) link, hybrid22 modulation, inverter, pulsating-dc link (PDCL), soft switching,23 three phase.24 I. INTRODUCTION25 Apulsating-dc link

  17. Ultrananocrystalline diamond films with optimized dielectric properties for advanced RF MEMS capacitive switches

    DOE Patents [OSTI]

    Sumant, Anirudha V.; Auciello, Orlando H.; Mancini, Derrick C.

    2013-01-15T23:59:59.000Z

    An efficient deposition process is provided for fabricating reliable RF MEMS capacitive switches with multilayer ultrananocrystalline (UNCD) films for more rapid recovery, charging and discharging that is effective for more than a billion cycles of operation. Significantly, the deposition process is compatible for integration with CMOS electronics and thereby can provide monolithically integrated RF MEMS capacitive switches for use with CMOS electronic devices, such as for insertion into phase array antennas for radars and other RF communication systems.

  18. Experimental demonstration of interaction-free all-optical switching via the quantum Zeno effect

    E-Print Network [OSTI]

    Kevin T. McCusker; Yu-Ping Huang; Abijith Kowligy; Prem Kumar

    2013-01-31T23:59:59.000Z

    We experimentally demonstrate all-optical interaction-free switching using the quantum Zeno effect, achieving a high contrast of 35:1. The experimental data matches a zero-parameter theoretical model for several different regimes of operation, indicating a good understanding of the switch's characteristics. We also discuss extensions of this work that will allow for significantly improved performance, and the integration of this technology onto chip-scale devices.

  19. Binary and ternary gas mixtures for use in glow discharge closing switches

    DOE Patents [OSTI]

    Hunter, Scott R. (Oak Ridge, TN); Christophorou, Loucas G. (Oak Ridge, TN)

    1990-01-01T23:59:59.000Z

    Highly efficient binary and ternary gas mixtures for use in diffuse glow discharge closing switches are disclosed. The binary mixtures are combinations of helium or neon and selected perfluorides. The ternary mixtures are combinations of helium, neon, or argon, a selected perfluoride, and a small amount of gas that exhibits enhanced ionization characteristics. These mixtures are shown to be the optimum choices for use in diffuse glow discharge closing switches by virtue of the combined physio-electric properties of the mixture components.

  20. A centralized approach to bandwidth allocation and connection management in switched Lans

    E-Print Network [OSTI]

    Sankaran, Kumar

    1998-01-01T23:59:59.000Z

    A CENTRALIZED APPROACH TO BANDWIDTH ALLOCATION AND CONNECTION MANAGEMENT IN SWITCHED LANS A Thesis by KUMAR SANKARAN Submitted to the Office of Graduate Studies of Texas ASM University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE May 1998 Major Subject: Computer Science A CENTRALIZED APPROACH TO BANDWIDTH ALLOCATION AND CONNECTION MANAGEMENT IN SWITCHED LANS A Thesis by KUMAR SANKARAN Submitted to Texas A&M University in partial fulfillment...

  1. Effects of finite gain-bandwidth products on switched capacitor filters

    E-Print Network [OSTI]

    Marciano, Frederic D.

    1985-01-01T23:59:59.000Z

    . 'vlav 198o Major Subject: Electrical Engineering EFFECTS OF FINITE GAIN-BANDWIDTH PRODUCTS ON SWITCHED CAPACITOR FILTERS A Thesis by FREDERIC D. MARCIANO Approved as to style and content by: o re E. Sanchez-Sinencio (Chairman of Committee... Chairman of Advisory Committee: Dr. E. Sanchez-Sinencio A methodology for the systematic study of the effects of finite gain-bandwidth products on switched capacitor filters is presented. The algorithms are established for a general structure comprising...

  2. Method for wiring allocation and switch configuration in a multiprocessor environment

    DOE Patents [OSTI]

    Aridor, Yariv (Zichron Ya'akov, IL); Domany, Tamar (Kiryat Tivon, IL); Frachtenberg, Eitan (Jerusalem, IL); Gal, Yoav (Haifa, IL); Shmueli, Edi (Haifa, IL); Stockmeyer, legal representative, Robert E. (San Jose, CA); Stockmeyer, Larry Joseph (San Jose, CA)

    2008-07-15T23:59:59.000Z

    A method for wiring allocation and switch configuration in a multiprocessor computer, the method including employing depth-first tree traversal to determine a plurality of paths among a plurality of processing elements allocated to a job along a plurality of switches and wires in a plurality of D-lines, and selecting one of the paths in accordance with at least one selection criterion.

  3. Deterministic Arbitrary Switching of Polarization in a Ferroelectric Thin Film

    SciTech Connect (OSTI)

    Vasudevan, Rama K [ORNL; Matsumoto, Yuji [Tohoku University, Sendai, Japan; Cheng, Xuan [University of New South Wales, Sydney, Australia; Imai, Akira [Tokyo Institute of Technology; Maruyama, Shingo [Tohoku University, Sendai, Japan; Xin, Huolin L. [Brookhaven National Laboratory (BNL); Okatan, Mahmut B [ORNL; Jesse, Stephen [ORNL; Kalinin, Sergei V [ORNL; Nagarajan, Valanoor [University of New South Wales

    2014-01-01T23:59:59.000Z

    Ferroelectrics have been used as memory storage devices, with an upper bound on the total possible memory levels generally dictated by the number of degenerate states allowed by the symmetry of the ferroelectric phase. Here, we introduce a new concept for storage wherein the polarization can be rotated arbitrarily, effectively decoupling it from the crystallographic symmetry of the ferroelectric phase on the mesoscale. By using a Bi5Ti3FeO15-CoFe2O4 film and via Band-Excitation Piezoresponse Force Microscopy, we show the ability to arbitrarily rotate polarization, create a spectrum of switched states, and suggest the reason for the polarization rotation is an abundance of sub-50nm nanodomains. Transmission electron microscopy-based strain mapping confirms significant local strain undulations imparted on the matrix by the CoFe2O4 inclusions, which causes significant local disorder. These experiments point to controlled tuning of polarization rotation in a standard ferroelectric, and hence the potential to greatly extend the attainable densities for ferroelectric memories.

  4. Site Characterization Report ORGDP Diffusion Facilities Permanent Shutdown K-700 Power House and K-27 Switch Yard/Switch House

    SciTech Connect (OSTI)

    Thomas R.J., Blanchard R.D.

    1988-06-13T23:59:59.000Z

    The K-700 Power House area, initially built to supply power to the K-25 gaseous diffusion plant was shutdown and disassembled in the 1960s. This shutdown was initiated by TVA supplying economical power to the diffusion plant complex. As a result of world wide over production of enriched, reactor grade U{sup 235}, the K-27 switch yard and switch house area was placed in standby in 1985. Subsequently, as the future production requirements decreased, the cost of production increased and the separation technologies for other processes improved, the facility was permanently shutdown in December, 1987. This Site Characterization Report is a part of the FY-88 engineering Feasibility Study for placing ORGDP Gaseous Diffusion Process facilities in 'Permanent Shutdown'. It is sponsored by the Department of Energy through Virgil Lowery of Headquarters--Enrichment and through Don Cox of ORO--Enrichment Operations. The primary purpose of these building or site characterization reports is to document, quantify, and map the following potential problems: Asbestos; PCB containing fluids; Oils, coolants, and chemicals; and External contamination. With the documented quantification of the concerns (problems) the Engineering Feasibility Study will then proceed with examining the potential solutions. For this study, permanent shutdown is defined as the securing and/or conditioning of each facility to provide 20 years of safe service with minimal expenditures and, where feasible, also serving DOE's needs for long-term warehousing or other such low-risk use. The K-700 power house series of buildings were either masonry construction or a mix of masonry and wood. The power generating equipment was removed and sold as salvage in the mid 1960s but the buildings and auxiliary equipment were left intact. The nine ancillary buildings in the power house area use early in the Manhattan Project for special research projects, were left intact minus the original special equipment. During the late 1960s and 1970s, some of the abandoned buildings were used for offices, special projects, and storage. Some of the remaining electrical transformers contain PCBs in concentrations less than 500 ppm. Many of the steam and hot water pipes in the buildings are insulated with asbestos insulation, but none of the equipment or buildings have high counts of surface radioactive contamination. The general conditions of the buildings are from fair to poor. Many should be boarded-up to prevent personnel entry and in some cases demolitions would be the safer alternative.

  5. LASER TRIGGERED GAS SWITCHES UTILIZING BEAM TRANSPORT THROUGH 1 MO-cm DEIONIZED WATER.

    SciTech Connect (OSTI)

    Woodworth, Joseph Ray; Lehr, Jane [Sandia National Laboratories, Albuquerque, NM; Blickem, James R.; Wallace, Zachariah R.; Anaya, Victor Jr; Corley, John P; Lott, John; Hodge, Keith; Zameroski, Nathan D. [Sandia National Laboratories, Albuquerque, NM

    2005-11-01T23:59:59.000Z

    We report on the successful attempts to trigger high voltage pressurized gas switches by utilizing beam transport through 1 MO-cm deionized water. The wavelength of the laser radiation was 532 nm. We have investigated Nd: YAG laser triggering of a 6 MV, SF6 insulated gas switch for a range of laser and switch parameters. Laser wavelength of 532 nm with nominal pulse lengths of 10 ns full width half maximum (FWHM) were used to trigger the switch. The laser beam was transported through 67 cm-long cell of 1 MO-cm deionized water constructed with anti reflection UV grade fused silica windows. The laser beam was then focused to form a breakdown arc in the gas between switch electrodes. Less than 10 ns jitter in the operation of the switch was obtained for laser pulse energies of between 80-110 mJ. Breakdown arcs more than 35 mm-long were produced by using a 70 cm focusing optic.

  6. A switched state feedback law for the stabilization of LTI systems.

    SciTech Connect (OSTI)

    Santarelli, Keith R.

    2009-09-01T23:59:59.000Z

    Inspired by prior work in the design of switched feedback controllers for second order systems, we develop a switched state feedback control law for the stabilization of LTI systems of arbitrary dimension. The control law operates by switching between two static gain vectors in such a way that the state trajectory is driven onto a stable n - 1 dimensional hyperplane (where n represents the system dimension). We begin by briefly examining relevant geometric properties of the phase portraits in the case of two-dimensional systems to develop intuition, and we then show how these geometric properties can be expressed as algebraic constraints on the switched vector fields that are applicable to LTI systems of arbitrary dimension. We then derive necessary and sufficient conditions to ensure stabilizability of the resulting switched system (characterized primarily by simple conditions on eigenvalues), and describe an explicit procedure for designing stabilizing controllers. We then show how the newly developed control law can be applied to the problem of minimizing the maximal Lyapunov exponent of the corresponding closed-loop state trajectories, and we illustrate the closed-loop transient performance of these switched state feedback controllers via multiple examples.

  7. A Switching Control Approach to Haptic Exploration for Quality Grasps

    E-Print Network [OSTI]

    Fagg, Andrew H.

    , Andrew H. Fagg Symbiotic Computing Laboratory University of Oklahoma Norman, OK 73072 Abstract-- Robotic and Andrew H. Fagg: School of Computer Science, [di|fagg]@cs.ou.edu Brian T. Watson: School of Mechanical

  8. Damage threshold and focusability of mid-infrared free-electron laser pulses gated by a plasma mirror with nanosecond switching pulses

    SciTech Connect (OSTI)

    Wang, Xiaolong; Nakajima, Takashi; Zen, Heishun; Kii, Toshiteru; Ohgaki, Hideaki [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)] [Institute of Advanced Energy, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan)

    2013-11-04T23:59:59.000Z

    The presence of a pulse train structure of an oscillator-type free-electron laser (FEL) results in the immediate damage of a solid target upon focusing. We demonstrate that the laser-induced damage threshold can be significantly improved by gating the mid-infrared FEL pulses with a plasma mirror. Although the switching pulses we employ have a nanosecond duration which does not guarantee the clean wavefront of the gated FEL pulses, the high focusability is experimentally confirmed through the observation of spectral broadening by a factor of 2.1 when we tightly focus the gated FEL pulses onto the Ge plate.

  9. Infrasonic observations of the Northridge, California, earthquake

    SciTech Connect (OSTI)

    Mutschlecner, J.P.; Whitaker, R.W.

    1994-09-01T23:59:59.000Z

    Infrasonic waves from the Northridge, California, earthquake of 17 January 1994 were observed at the St. George, Utah, infrasound array of the Los Alamos National Laboratory. The distance to the epicenter was 543 kilometers. The signal shows a complex character with many peaks and a long duration. An interpretation is given in terms of several modes of signal propagation and generation including a seismic-acoustic secondary source mechanism. A number of signals from aftershocks are also observed.

  10. Heavy Mobile Equipment Mechanic (One Mechanic Shop)

    Broader source: Energy.gov [DOE]

    The position is a Heavy Mobile Equipment Mechanic (One Mechanic Shop) located in Kent, Washington, and will be responsible for the safe and efficient operation of a field garage performing...

  11. Effects of ZrO{sub 2} doping on HfO{sub 2} resistive switching memory characteristics

    SciTech Connect (OSTI)

    Ryu, Seung Wook; Kwac, Jungsuk; Nishi, Yoshio [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Cho, Seongjae, E-mail: felixcho@gachon.ac.kr [Department of Electronic Engineering and New Technology Component and Material Research Center (NCMRC), Gachon University, Seongnam-si, Gyeonggi-do 461-741 (Korea, Republic of); Park, Joonsuk [Department of Materials Science and Engineering, Stanford University, Stanford, California 94305 (United States); Kim, Hyeong Joon [Department of Materials Science and Engineering and Inter-university Semiconductor Research Center (ISRC), Seoul National University, Seoul 151-744 (Korea, Republic of)

    2014-08-18T23:59:59.000Z

    A resistive switching (RS) random access memory device with ZrO{sub 2}-doped HfO{sub 2} exhibits better RS performance than that with pure HfO{sub 2}. In particular, I{sub res}, V{sub res}, and V{sub set} are reduced by approximately 58%, 38%, and 39%, respectively, when HfO{sub 2} is doped with ZrO{sub 2} (9 at.?%). In addition, the ZrO{sub 2} doping in HfO{sub 2} makes the distribution of most parameters steeper. Transmission electron microscopy (TEM) analysis reveals that the deposited zirconium-doped hafnium oxide (HZO) (9 at.?%) is polycrystalline. Elemental mapping results by scanning TEMenergy dispersive spectroscopy also prove that ZrO{sub 2} is uniformly distributed in the HZO (9 at.?%) film. The possible mechanism for the improvement in the RS characteristics is also suggested on the basis of the X-ray photoelectron spectroscopy results and filamentary RS mechanism. These results suggest that the ZrO{sub 2} doping into HfO{sub 2} likely not only will reduce power consumption but also will improve cyclic endurance by controlling the nonstoichiometric phase.

  12. Demonstration of the Feasibility of Large Port Count Optical Switching Using a Hybrid MZI SOA Switch Module in a Recirculating Loop

    E-Print Network [OSTI]

    Cheng, Q.; Wonfor, A.; Wei, J. L.; Penty, R. V.; White, I. H.

    2014-09-02T23:59:59.000Z

    88. [3] S. Sohma, T. Watanabe, N. Ooba, M. Itoh, T. Shibata, and H. Takahashi, Silica-based PLC Type 32 x 32 Optical Matrix Switch, 2006 European Conference on Optical Communications, pp. 12, Sep. 2006. [4] F. L. W. Rabbering, J. F. P. van Nunen...

  13. E-beam high voltage switching power supply

    DOE Patents [OSTI]

    Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

    1997-01-01T23:59:59.000Z

    A high power, solid state power supply is described for producing a controllable, constant high voltage output under varying and arcing loads suitable for powering an electron beam gun or other ion source. The present power supply is most useful for outputs in a range of about 100-400 kW or more. The power supply is comprised of a plurality of discrete switching type dc-dc converter modules, each comprising a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, and an output rectifier for producing a dc voltage at the output of each module. The inputs to the converter modules are fed from a common dc rectifier/filter and are linked together in parallel through decoupling networks to suppress high frequency input interactions. The outputs of the converter modules are linked together in series and connected to the input of the transmission line to the load through a decoupling and line matching network. The dc-dc converter modules are phase activated such that for n modules, each module is activated equally 360.degree./n out of phase with respect to a successive module. The phased activation of the converter modules, combined with the square current waveforms out of the step up transformers, allows the power supply to operate with greatly reduced output capacitance values which minimizes the stored energy available for discharge into an electron beam gun or the like during arcing. The present power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle using simulated voltage feedback signals and voltage feedback loops. Circuitry is also provided for sensing incipient arc currents reflected at the output of the power supply and for simultaneously decoupling the power supply circuitry from the arcing load.

  14. E-beam high voltage switching power supply

    DOE Patents [OSTI]

    Shimer, D.W.; Lange, A.C.

    1997-03-11T23:59:59.000Z

    A high power, solid state power supply is described for producing a controllable, constant high voltage output under varying and arcing loads suitable for powering an electron beam gun or other ion source. The present power supply is most useful for outputs in a range of about 100-400 kW or more. The power supply is comprised of a plurality of discrete switching type dc-dc converter modules, each comprising a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, and an output rectifier for producing a dc voltage at the output of each module. The inputs to the converter modules are fed from a common dc rectifier/filter and are linked together in parallel through decoupling networks to suppress high frequency input interactions. The outputs of the converter modules are linked together in series and connected to the input of the transmission line to the load through a decoupling and line matching network. The dc-dc converter modules are phase activated such that for n modules, each module is activated equally 360{degree}/n out of phase with respect to a successive module. The phased activation of the converter modules, combined with the square current waveforms out of the step up transformers, allows the power supply to operate with greatly reduced output capacitance values which minimizes the stored energy available for discharge into an electron beam gun or the like during arcing. The present power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle using simulated voltage feedback signals and voltage feedback loops. Circuitry is also provided for sensing incipient arc currents reflected at the output of the power supply and for simultaneously decoupling the power supply circuitry from the arcing load. 7 figs.

  15. Observability of Neuronal Network Motifs (Invited Paper)

    E-Print Network [OSTI]

    Brennan, Sean

    Observability of Neuronal Network Motifs (Invited Paper) Andrew J. Whalen*t, Sean N. Brennan Engineering, + Engineering Science and Mechanics, Neurosurgery, and Physics, Penn State University, University) neuronal networks as a function of 1) the connection topology and sym metry, 2) the measured nodes, and 3

  16. Mechanical & Industrial Engineering

    E-Print Network [OSTI]

    Mountziaris, T. J.

    Mechanical & Industrial Engineering 1 Welcome MIE Industrial Advisory Board October 15, 2010 #12;Mechanical & Industrial Engineering 2 MIE Dorothy Adams Undergraduate/Graduate Secretary David Schmidt Associate Professor & Graduate Program Director #12;Mechanical & Industrial Engineering 3 MIE James Rinderle

  17. Mechanical Engineering & Thermal Group

    E-Print Network [OSTI]

    Mojzsis, Stephen J.

    Mechanical Engineering & Thermal Group The Mechanical Engineering (ME) & Thermal Group at LASP has STOP (Structural, Thermal, and Optical Performance) analyses of optical systems Thermal engineers lead evolved with the complexity of instrument design demands, LASP mechanical engineers develop advanced

  18. Mechanical engineering Department Seminar

    E-Print Network [OSTI]

    and the Department of Mechanical Engineering Tufts University Retooling Our Energy Ecosystem: challengesMechanical engineering Department Seminar Robert J. Hannemann The Gordon Institute and Chair of the Tufts Department of Mechanical Engineering. His technical and academic interests

  19. Observation of transient gain without population inversion in a laser-cooled rubidium lambda system

    E-Print Network [OSTI]

    S. R. de Echaniz; Andrew D. Greentree; A. V. Durrant; D. M. Segal; J. P. Marangos; J. A. Vaccaro

    2001-05-17T23:59:59.000Z

    We have observed clear Rabi oscillations of a weak probe in a strongly driven three-level lambda system in laser-cooled rubidium for the first time. When the coupling field is non-adiabatically switched on using a Pockels cell, transient probe gain without population inversion is obtained in the presence of uncoupled absorptions. Our results are supported by three-state computations.

  20. Hot Pot Field Observations

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Lane, Michael

    Map of field observations including depressions, springs, evidence of former springs, travertine terraces and vegetation patterns. Map also contains interpretation of possible spring alignments.

  1. Hot Pot Field Observations

    SciTech Connect (OSTI)

    Lane, Michael

    2013-06-28T23:59:59.000Z

    Map of field observations including depressions, springs, evidence of former springs, travertine terraces and vegetation patterns. Map also contains interpretation of possible spring alignments.

  2. Mechanical & Aerospace Engineering

    E-Print Network [OSTI]

    Mechanical & Aerospace Engineering It is a new beginning for innovative fundamental and applied and consolidation of bulk nanocrystalline materials using mechanical alloying, the alloy development and synthesis

  3. Surface Plasmon Polariton Assisted Optical Switching in Noble Metal Nanoparticle Systems: A Sub-Band Gap Approach

    E-Print Network [OSTI]

    Dhara, S

    2015-01-01T23:59:59.000Z

    In a proposed book chapter surface plasmon polariton assisted optical switching in noble metal nanoparticle systems is discussed in the sub-band gap formalism.

  4. A local switch Markov chain on given degree graphs with application in connectivity of Peer-to-Peer networks

    E-Print Network [OSTI]

    Saberi, Amin

    -to-Peer networks Tomas Feder Adam Guetz Milena Mihail Amin Saberi Abstract We study a switch Markov chain

  5. Design and analysis of a zero-voltage switching scheme for a dc- to-dc converter

    E-Print Network [OSTI]

    Arun, G.

    1992-01-01T23:59:59.000Z

    5S 59 VITA . 65 I. IST OF FICI;RES FIGURE Page Linear versus switch-mode power convers&on Components of a switch-mode dc-to-dc converter 3 A typical dc-to-dc converter system Basic buck converter Basic boost converter Basic buck...-boost converter 7 One leg of a, dc-to-dc converter. Turn-on and turn-off scenartos in switch-mode operation. 16 10 Switching loci in the ur ? ir plane. Circuit for. zero-voltage sw&tching. . Mode 1 17 90 Mode? Mode I Mode 5 oo 93 Typical voltage...

  6. 14 ESS (trademark) switch inherent radiation-hardness assessment. Volume 2. Appendices to final report. Final report

    SciTech Connect (OSTI)

    Not Available

    1990-07-01T23:59:59.000Z

    The objective of Phase I of the 4 ESS Switch RHA Program document in this report is the preliminary assessment of the Inherent fallout-radiation susceptibility of the 4 ESS Switch. The approach described herein consists of the identification of the active microelectronic piece-parts used in the 4 ESS Switch; characterization of their radiation tolerance, based on available data; preliminary identification of hardness-critical packs; and preliminary analysis of 4 ESS Switch performance during export to ambient (unshielded) fallout radiation, also based on available data.

  7. The continuum and wave mechanics

    E-Print Network [OSTI]

    Collins, Royal Eugene

    1954-01-01T23:59:59.000Z

    in the realm of our actual experience we find it possi? ble to define operational procedures for observing and 4 , and we A find that these procedures always yield values of ?f and "t . Further? more we always find that the observed values of the position... in our analysis of Classical Mechanics, therefore we now consider the following problem. If we consider w quantities iT HE M gnx DHqMyco and p? quantities-[ yO 4. to be defined by operations can we require that a function yA ? t j exists...

  8. The universal criterion for switching a magnetic vortex core in soft magnetic nanodots

    SciTech Connect (OSTI)

    Lee, K.-S.; Kim, S.-K.; Yu, Y.-S.; Choi, Y.-S.; Guslienko, K. Y.; Jung, H.; Fischer, P.

    2008-10-01T23:59:59.000Z

    The universal criterion for ultrafast vortex core switching between core-up and -down vortex bi-states in soft magnetic nanodots was empirically investigated by micromagnetic simulations and combined with an analytical approach. Vortex-core switching occurs whenever the velocity of vortex core motion reaches a critical value, which is {nu}{sub c} = 330 {+-} 37 m/s for Permalloy, as estimated from numerical simulations. This critical velocity was found to be {nu}{sub c} = {eta}{sub c}{gamma} {radical}A{sub ex} with A{sub ex} the exchange stiffness, {gamma} the gyromagnetic ratio, and an estimated proportional constant {eta}{sub c} = 1.66 {+-} 0.18. This criterion does neither depend on driving force parameters nor on the dimension or geometry of the magnetic specimen. The phase diagrams for the vortex core switching criterion and its switching time with respect to both the strength and angular frequency of circular rotating magnetic fields were derived, which offer practical guidance for implementing vortex core switching into future solid state information storage devices.

  9. A Soft-Switching Inverter for High-Temperature Advanced Hybrid Electric Vehicle Traction Motor Drives

    SciTech Connect (OSTI)

    None, None

    2012-01-31T23:59:59.000Z

    The state-of-the-art hybrid electric vehicles (HEVs) require the inverter cooling system to have a separate loop to avoid power semiconductor junction over temperatures because the engine coolant temperature of 105?C does not allow for much temperature rise in silicon devices. The proposed work is to develop an advanced soft-switching inverter that will eliminate the device switching loss and cut down the power loss so that the inverter can operate at high-temperature conditions while operating at high switching frequencies with small current ripple in low inductance based permanent magnet motors. The proposed tasks also include high-temperature packaging and thermal modeling and simulation to ensure the packaged module can operate at the desired temperature. The developed module will be integrated with the motor and vehicle controller for dynamometer and in-vehicle testing to prove its superiority. This report will describe the detailed technical design of the soft-switching inverters and their test results. The experiments were conducted both in module level for the module conduction and switching characteristics and in inverter level for its efficiency under inductive and dynamometer load conditions. The performance will be compared with the DOE original specification.

  10. Tunnel MOS Heterostructure Field Effect Transistor for RF Switching Applications

    E-Print Network [OSTI]

    Rezanezhad Gatabi, Iman

    2013-06-06T23:59:59.000Z

    6 dry etching on the trap density and trap state energy of AlGaN surface are investigated using the GP/w- w method. Various tunneling mechanisms at different biases are then characterized in samples and compared with each other. To improve...

  11. Ann Occup Hyg . Author manuscript Asbestos-related diseases in automobile mechanics

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Ann Occup Hyg . Author manuscript Page /1 7 Asbestos-related diseases in automobile mechanics Abstract Purpose Automobile mechanics have been exposed to asbestos number of automobile mechanics, little is known about the non-malignant respiratory diseases observed

  12. Combined Quantum Mechanical and Molecular Mechanics Studies of...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Mechanical and Molecular Mechanics Studies of the Electron-Transfer Reactions Involving Carbon Tetrachloride in Combined Quantum Mechanical and Molecular Mechanics Studies of the...

  13. Mechanical engineering Department Seminar

    E-Print Network [OSTI]

    Lin, Xi

    Mechanical engineering Department Seminar Ju Li Professor MIT Electrochemical-mechanical actions computational and experimental research on mechanical properties of materials, and energy storage and conversion Refreshments served at 10:45 AM The creation of a nanoscale electrochemical and mechanical testing platform

  14. Discretetime Observers and Synchronization

    E-Print Network [OSTI]

    Eindhoven, Technische Universiteit

    . Pogromsky 3 1. Faculty of Mathematics and Computing Science, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands hjch@win.tue.nl 2. Faculty of Mathematical Sciences of Mechanical Engineering, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands

  15. An efficient all-optical switch using a lambda atom in a cavity QED system

    E-Print Network [OSTI]

    Anne E. B. Nielsen; Joseph Kerckhoff

    2014-10-09T23:59:59.000Z

    We propose an all-optical switch constructed from a two-mode optical resonator containing a strongly coupled, three-state system. The coupling allows a weak, continuous wave laser drive to incoherently control the transmission of a much stronger, continuous wave signal laser into (and through) the resonator. We demonstrate that in this simple setup the presence of a control drive with one tenth the power of the signal drive can induce near complete reflection of the signal, while its absence allows for near complete transmission. The switch can also be operated as a set-reset relay with two control inputs that efficiently drive the switch into either the reflecting or the transmitting state.

  16. Semiconductor diode laser having an intracavity spatial phase controller for beam control and switching

    DOE Patents [OSTI]

    Hohimer, John P. (Albuquerque, NM)

    1994-01-01T23:59:59.000Z

    A high-power broad-area semiconductor laser having a intracavity spatial phase controller is disclosed. The integrated intracavity spatial phase controller is easily formed by patterning an electrical contact metallization layer when fabricating the semiconductor laser. This spatial phase controller changes the normally broad far-field emission beam of such a laser into a single-lobed near-diffraction-limited beam at pulsed output powers of over 400 mW. Two operating modes, a thermal and a gain operating mode, exist for the phase controller, allowing for steering and switching the beam as the modes of operation are switched, and the emission beam may be scanned, for example, over a range of 1.4 degrees or switched by 8 degrees. More than one spatial phase controller may be integrated into the laser structure.

  17. Rapid switching in electrochromic devices based on complementary conducting polymer films

    SciTech Connect (OSTI)

    Sapp, S.A.; Sotzing, G.A.; Reddinger, J.L.; Reynolds, J.R. [Univ. of Florida, Gainesville, FL (United States)

    1996-10-01T23:59:59.000Z

    The search for stable, rapid switching electrochromic materials that are easy and inexpensive to process has become the focus of a great deal of research in the past few years. Conducting and electroactive polymers are one class of electrochromic materials which may offer a low cost alternative to the traditional metal oxide materials that have been studied in depth. These materials also offer the advantages of having rapid switching rates and a well defined chemical structure. Recently, there have been many new conducting polymer systems developed which exhibit complementary electrochromic behavior and undergo reversible redox chemistry. This presentation will focus on the design, fabrication, and characterization of electrochromic devices based on complementary conducting polymers as cathodic and anodic electrochromic materials. Spectroelectrochemistry results and switching rate determinations will be discussed for two of these polymer based electrochromic devices.

  18. Analysis and Design of an Organic High Speed Digital Electro-Optic Switch

    E-Print Network [OSTI]

    Ali Akbar Wahedy Zarch; Hassan Kaatuzian; Ahmad Ajdarzadeh Oskouei; Ahmad Amjadi

    2007-05-09T23:59:59.000Z

    We have analyzed and designed an organic high speed digital optical switch (DOS) based on transverse electro-optic effect. In analysis section, we proposed a quantum photonic model (QPM) to explain linear electro-optic (EO) effect. This model interpret this effect by photon-electron interaction in attosecond regime. We simulate applied electric field on molecule and crystal by Monte-Carlo method in time domain. We show how a waveguide response to an optical signal with different wavelengths when a transverse electric field applied to the waveguide. In design section, we configure conceptually a 2 * 2 EO switch with full adiabatic coupler. In this DOS, we use a rib waveguides that its core has been constructed from NPP crystal. This switch is smaller at least to one-half of similar DOS in dimensions.

  19. Analysis and Design of an Organic High Speed Digital Electro-Optic Switch

    E-Print Network [OSTI]

    Zarch, Ali Akbar Wahedy; Oskouei, Ahmad Ajdarzadeh; Amjadi, Ahmad

    2007-01-01T23:59:59.000Z

    We have analyzed and designed an organic high speed digital optical switch (DOS) based on transverse electro-optic effect. In analysis section, we proposed a quantum photonic model (QPM) to explain linear electro-optic (EO) effect. This model interpret this effect by photon-electron interaction in attosecond regime. We simulate applied electric field on molecule and crystal by Monte-Carlo method in time domain. We show how a waveguide response to an optical signal with different wavelengths when a transverse electric field applied to the waveguide. In design section, we configure conceptually a 2 * 2 EO switch with full adiabatic coupler. In this DOS, we use a rib waveguides that its core has been constructed from NPP crystal. This switch is smaller at least to one-half of similar DOS in dimensions.

  20. Semiconductor diode laser having an intracavity spatial phase controller for beam control and switching

    DOE Patents [OSTI]

    Hohimer, J.P.

    1994-06-07T23:59:59.000Z

    A high-power broad-area semiconductor laser having a intracavity spatial phase controller is disclosed. The integrated intracavity spatial phase controller is easily formed by patterning an electrical contact metallization layer when fabricating the semiconductor laser. This spatial phase controller changes the normally broad far-field emission beam of such a laser into a single-lobed near-diffraction-limited beam at pulsed output powers of over 400 mW. Two operating modes, a thermal and a gain operating mode, exist for the phase controller, allowing for steering and switching the beam as the modes of operation are switched, and the emission beam may be scanned, for example, over a range of 1.4 degrees or switched by 8 degrees. More than one spatial phase controller may be integrated into the laser structure. 6 figs.

  1. Self-Q-switching behavior of erbium-doped tellurite microstructured fiber lasers

    SciTech Connect (OSTI)

    Jia, Zhi-Xu; Yao, Chuan-Fei; Kang, Zhe; Qin, Guan-Shi, E-mail: qings@jlu.edu.cn; Qin, Wei-Ping, E-mail: wpqin@jlu.edu.cn [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012 (China); Ohishi, Yasutake [Research Center for Advanced Photon Technology, Toyota Technological Institute, 2-12-1 Hisakata, Tempaku, Nagoya 468-8511 (Japan)

    2014-06-14T23:59:59.000Z

    We reported self-Q-switching behavior of erbium-doped tellurite microstructured fiber (EDTMF) lasers and further demonstrated a self-Q-switched EDTMF laser with a high repetition rate of more than 1?MHz. A 14?cm EDTMF was used as the gain medium. Upon a pump power of ?705?mW at 1480?nm, output pulses with a lasing wavelength of ?1558?nm, a repetition rate of ?1.14?MHz, and a pulse width of ?282?ns were generated from the fiber by employing a linear cavity. The maximum output power was ?316 mW and the slope efficiency was about 72.6% before the saturation of the laser power. Moreover, the influence of the fiber length on laser performances was investigated. The results showed that self-Q-switching behavior in our experiments was caused by the re-absorption originated from the ineffectively pumped part of the active fiber.

  2. Bimodal switching field distributions in all-perpendicular spin-valve nanopillars

    SciTech Connect (OSTI)

    Gopman, D. B., E-mail: daniel.gopman@physics.nyu.edu; Kent, A. D. [Department of Physics, New York University, New York, New York 10003 (United States); Bedau, D.; Katine, J. A. [HGST San Jose Research Center, San Jose, California 95135 (United States); Mangin, S. [Institut Jean Lamour, UMR CNRS 7198 Universit de Lorraine, Nancy (France); Fullerton, E. E. [CMRR, University of California at San Diego, La Jolla, California 92093 (United States)

    2014-05-07T23:59:59.000Z

    Switching field measurements of the free layer element of 75?nm diameter spin-valve nanopillars reveal a bimodal distribution of switching fields at low temperatures (below 100?K). This result is inconsistent with a model of thermal activation over a single perpendicular anisotropy barrier. The correlation between antiparallel to parallel and parallel to antiparallel switching fields increases to nearly 50% at low temperatures. This reflects random fluctuation of the shift of the free layer hysteresis loop between two different magnitudes, which may originate from changes in the dipole field from the polarizing layer. The magnitude of the loop shift changes by 25% and is correlated to transitions of the spin-valve into an antiparallel configuration.

  3. Observational learning in horses

    E-Print Network [OSTI]

    Baer, Katherine Louise

    1979-01-01T23:59:59.000Z

    . One group served as control subjects while the other group functioned as a treated group (observers). The observers were allowed to watch a correctly performed discrimination task prior to testing of a learning response using the same task.... Discrimination testing was conducted on all horses daily for 14 days with criterion set at seven out of eight responses correct with the last five consecutively correct. The maximum number of trials performed without reaching set criterion was limited...

  4. New Switches for Utility-Scale Inverters: First In-Class Demonstration of a Completely New Type of SiC Bipolar Switch (15kV-20kV) for Utility-Scale Inverters

    SciTech Connect (OSTI)

    None

    2011-12-31T23:59:59.000Z

    Solar ADEPT Project: The SiCLAB is developing a new power switch for utility-scale PV inverters that would improve the performance and significantly reduce the size, weight, and energy loss of PV systems. A power switch controls the electrical energy flowing through an inverter, which takes the electrical current from a PV solar panel and converts it into the type and amount of electricity that is compatible with the electric grid. SiCLAB is using silicon carbide (SiC) semiconductors in its new power switches, which are more efficient than the silicon semiconductors used to conduct electricity in most conventional power switches today. Switches with SiC semiconductors can operate at much higher temperatures, as well as higher voltage and power levels than silicon switches. SiC-based power switches are also smaller than those made with silicon alone, so they result in much smaller and lighter electrical devices. In addition to their use in utility-scale PV inverters, SiCLABs new power switches can also be used in wind turbines, railways, and other smart grid applications.

  5. Mechanisms of chemical phototoxicity

    SciTech Connect (OSTI)

    Yurkow, E.J.

    1989-01-01T23:59:59.000Z

    Psoralens in combination with ultraviolet light (PUVA) are phototoxic and potent modulators of epidermal cell growth and differentiation. Using an in vitro cell culture model, the effects of psoralens and UVA light on the growth of epidermal cells were investigated. It was found that psoralen and UVA light interact synergistically to inhibit the growth of cells in culture. This synergism was also observed in the ability of PUVA to inhibit DNA synthesis, decrease cell survival, cause mutations and form psoralen-DNA adducts. Using a cell culture model for the differentiation of melanocytes, PUVA was also found to be a potent inducer of melanogenesis as evidenced by its ability to increase cellular tyrosinase, the enzyme responsible for melanin biosynthesis. Results from these studies indicate that PUVA can induce dramatic alterations in the growth rate and differentiation state of cells at dosage levels which are associated with minimal DNA damage. These findings are in conflict with the general assumption that the biological effects of psoralens and UVA light are associated with their ability to bind covalently to and cross-link DNA. Therefore, the author investigated the possibility that sites of action, other than DNA, are involved in the mechanism(s) by which photoactivated psoralens modulate epidermal cell growth and differentiation. The author's laboratory has found that mammalian epidermal cells contain specific, saturable, high-affinity binding sites for the psoralens that are distinct from DNA. This receptor for the psoralens, photolabeled with ({sup 3}H)-8-methoxysporalen, was visualized following sodium dodecyl sulfatepolyacrylamide gel electrophoresis. The psoralen receptor is shown to be a 22,000 dalton protein located in nonnuclear fractions of cell extracts.

  6. Towards forming-free resistive switching in oxygen engineered HfO{sub 2?x}

    SciTech Connect (OSTI)

    Sharath, S. U., E-mail: sharath@oxide.tu-darmstadt.de; Kurian, J.; Hildebrandt, E.; Alff, L. [Institute of Materials Science, Technische Universitt Darmstadt, Alarich-Weiss-Strasse 2, 64287 Darmstadt (Germany); Bertaud, T.; Walczyk, C.; Calka, P.; Zaumseil, P.; Sowinska, M.; Walczyk, D. [IHP, Im Technologiepark 25, 15236 Frankfurt Oder (Germany); Gloskovskii, A. [Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg (Germany); Schroeder, T. [IHP, Im Technologiepark 25, 15236 Frankfurt Oder (Germany); Brandenburgische Technische Universitt, Konrad-Zuse-Strasse 1, 03046 Cottbus (Germany)

    2014-02-10T23:59:59.000Z

    We have investigated the resistive switching behavior in stoichiometric HfO{sub 2} and oxygen-deficient HfO{sub 2?x} thin films grown on TiN electrodes using reactive molecular beam epitaxy. Oxygen defect states were controlled by the flow of oxygen radicals during thin film growth. Hard X-ray photoelectron spectroscopy confirmed the presence of sub-stoichiometric hafnium oxide and defect states near the Fermi level. The oxygen deficient HfO{sub 2?x} thin films show bipolar switching with an electroforming occurring at low voltages and low operating currents, paving the way for almost forming-free devices for low-power applications.

  7. An Improved SF6 System for the FXR Induction Linac Blumlein Switches

    SciTech Connect (OSTI)

    DeHope, W; Kihara, R; Griffin, K L; Ong, M; Ross, T

    2007-06-16T23:59:59.000Z

    The now-mature FXR (Flash X-Ray) radiographic facility at Lawrence Livermore National Laboratory will be briefly described with emphasis on its pulsed power system. The heart of each accelerating cell's pulse forming Blumlein is it's sulfur hexafluoride-based triggered closing switch. FXR's recent upgrade to a recirculating SF{sub 6} gas reclamation system will be described and the resulting accelerator performance and reliability improvements documented. This was accompanied by a detailed switch breakdown study on FXR's Test Stand and the recent analysis of the resulting statistics will be shown.

  8. Electrode with transparent series resistance for uniform switching of optical modulation devices

    SciTech Connect (OSTI)

    Tench, D. Morgan (Camarillo, CA); Cunningham, Michael A. (Thousand Oaks, CA); Kobrin, Paul H. (Newbury Park, CA)

    2008-01-08T23:59:59.000Z

    Switching uniformity of an optical modulation device for controlling the propagation of electromagnetic radiation is improved by use of an electrode comprising an electrically resistive layer that is transparent to the radiation. The resistive layer is preferably an innerlayer of a wide-bandgap oxide sandwiched between layers of indium tin oxide or another transparent conductor, and may be of uniform thickness, or may be graded so as to provide further improvement in the switching uniformity. The electrode may be used with electrochromic and reversible electrochemical mirror (REM) smart window devices, as well as display devices based on various technologies.

  9. Binary and ternary gas mixtures for use in glow discharge closing switches

    DOE Patents [OSTI]

    Hunter, S.R.; Christophorou, L.G.

    1988-04-27T23:59:59.000Z

    Highly efficient binary and ternary gas mixtures for use in diffuse glow discharge closing switches are disclosed. The binary mixtures are combinations of helium or neon and selected perfluorides. The ternary mixtures are combinations of helium, neon, or argon, a selected perfluoride, and a small amount of gas that exhibits enhanced ionization characteristics. These mixtures are shown to be the optimum choices for use in diffuse glow discharge closing switches by virtue if the combines physio-electric properties of the mixture components. 9 figs.

  10. Optimization of spin-torque switching using AC and DC pulses

    SciTech Connect (OSTI)

    Dunn, Tom [Department of Physics, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Kamenev, Alex [Department of Physics, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2014-06-21T23:59:59.000Z

    We explore spin-torque induced magnetic reversal in magnetic tunnel junctions using combined AC and DC spin-current pulses. We calculate the optimal pulse times and current strengths for both AC and DC pulses as well as the optimal AC signal frequency, needed to minimize the Joule heat lost during the switching process. The results of this optimization are compared against numeric simulations. Finally, we show how this optimization leads to different dynamic regimes, where switching is optimized by either a purely AC or DC spin-current, or a combination AC/DC spin-current, depending on the anisotropy energies and the spin-current polarization.

  11. Electro-optic harmonic conversion to switch a laser beam out of a cavity

    DOE Patents [OSTI]

    Haas, Roger A. (Pleasanton, CA); Henesian, Mark A. (Livermore, CA)

    1987-01-01T23:59:59.000Z

    The invention is a switch to permit a laser beam to escape a laser cavity through the use of an externally applied electric field across a harmonic conversion crystal. Amplification takes place in the laser cavity, and then the laser beam is switched out by the laser light being harmonically converted with dichroic or polarization sensitive elements present to alter the optical path of the harmonically converted laser light. Modulation of the laser beam can also be accomplished by varying the external electric field.

  12. Abstract--The switched reluctance motor (SRM) has become an interesting concept of electro-mechanical energy

    E-Print Network [OSTI]

    Paderborn, Universitt

    windings, either the stator or the rotor. The SRM topology with the rotor solely consisting of laminations contactless from the stator to the rotor with additional windings is investigated in this paper. Magnetizing construction. In this paper, the transfer of electrical energy from the stator to the rotor with additional

  13. Minimizing Simultaneous Switching Noise at Reduced Power with Constant-Voltage Power Transmission Lines for High-Speed Signaling

    E-Print Network [OSTI]

    Swaminathan, Madhavan

    plane structure with a power transmission line (PTL). In this paper, a new power delivery scheme called Constant Voltage Power Transmission Line (CV-PTL) is shown to significantly reduce switching noise while, and measurements. Keywords Power delivery network, simultaneous switching noise, power transmission line 1

  14. Design of Stabilizing Switching Control Laws for Discrete and Continuous-Time Linear Systems Using Piecewise-Linear

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    Koutsoukos, Xenofon D.

    Design of Stabilizing Switching Control Laws for Discrete and Continuous-Time Linear Systems Using Piecewise-Linear Lyapunov Functions Xenofon D. Koutsoukos Palo Alto Research Center 3333 Coyote Hill Road-219-631-5792 Fax +1-219-631-4393 antsaklis.1@nd.edu Abstract In this paper, the stability of switched linear

  15. Shields et al. Predictive Control for Time-Delayed ... Predictive Control for Time-Delayed Switching Control Systems

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    is proposed for the control of switching systems characterized by linear system dynamics with a time delay that will take the system closest to the desired future state. The resulting control action is sub-optimal by linear dynamics with a time-delayed input. A switching control system (as defined herein) is one

  16. Hydrogen Bond Switching among Flavin and Amino Acids Determines the Nature of Proton-Coupled Electron Transfer in BLUF

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    van Stokkum, Ivo

    Hydrogen Bond Switching among Flavin and Amino Acids Determines the Nature of Proton results from a hydrogen bond switch between the flavin and its surrounding amino acids that preconfigures a rearrangement of the hydrogen bond network around the flavin takes place leading to a 10-15 nm red shift

  17. Polarization-insensitive thermo-optic switch based on multimode polymeric waveguides with an ultralarge optical bandwidth

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    Chen, Ray

    Polarization-insensitive thermo-optic switch based on multimode polymeric waveguides polarization-insensitive thermo-optic switch based on multimode polymeric waveguides is reported. This device than 20 dB can be achieved with the deviceelectrode interaction length of 30 mm. The thermo

  18. 3-D Computational Modeling of RF MEMS Switches H. D. Espinosa, M. Fischer, Y. Zhu and S. Lee

    E-Print Network [OSTI]

    Espinosa, Horacio D.

    in this work by means of wafer level experimental techniques. RF MEMS Switches manufactured by Raytheon Systems, Raytheon Systems Co. developed MEMS switches to operate in tunable filters and oscillators used by Raytheon Systems Co. (b) Top view of the "bow-tie" membrane mounted on posts. It is made of an aluminum

  19. A Cost-Effective Design for ATM Switching Fabrics* Nian-Feng Tzeng, Kiran Ponnuru, and Kemathat Vibhatavanij

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    Tzeng, Nian-Feng

    ). The design consists of repeated copies of multiple stages of SEs, that are interconnected according for constructing a larger switching fabric according to a certain interconnection style. A shared-memory ATM switch/Cooperative Agreement No. DAAG55-98-1-0240. standpoint, it is efficient to have buffer storage shared by all the output

  20. DyPS: Dynamic Processor Switching for Energy-Aware Video Decoding on Multi-core SoCs

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    Paris-Sud XI, Universit de

    DyPS: Dynamic Processor Switching for Energy-Aware Video Decoding on Multi-core SoCs Yahia approach for energy-aware processor switching (GPP or DSP) according to the video quality. We show better performance and low energy consumption prop- erties. However, the experimental measurements we