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Sample records for wire-compatible switching fabric

  1. Internal Backpressure for Terabit Switch Fabrics

    DEFF Research Database (Denmark)

    Fagertun, Anna Manolova; Ruepp, Sarah Renée; Rytlig, Andreas

    2012-01-01

    This paper proposes and analyzes the efficiency of novel backpressure schemes for Terabit switch fabrics. The proposed schemes aim at buffer optimization under uniform traffic distribution with Bernoulli packet arrival process. Results show that a reduction of the needed maximum buffer capacity w...... with up to 47% can be achieved with switch-internal backpressure mechanisms at the expense of a small control overhead....

  2. A Novel Silicon-based Wideband RF Nano Switch Matrix Cell and the Fabrication of RF Nano Switch Structures

    Directory of Open Access Journals (Sweden)

    Yi Xiu YANG

    2011-12-01

    Full Text Available This paper presents the concept of RF nano switch matrix cell and the fabrication of RF nano switch. The nano switch matrix cell can be implemented into complex switch matrix for signal routing. RF nano switch is the decision unit for the matrix cell; in this research, it is fabricated on a tri-layer high-resistivity-silicon substrate using surface micromachining approach. Electron beam lithography is introduced to define the pattern and IC compatible deposition process is used to construct the metal layers. Silicon-based nano switch fabricated by IC compatible process can lead to a high potential of system integration to perform a cost effective system-on-a-chip solution. In this paper, simulation results of the designed matrix cell are presented; followed by the details of the nano structure fabrication and fabrication challenges optimizations; finally, measurements of the fabricated nano structure along with analytical discussions are also discussed.

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

    Science.gov (United States)

    Walker, Charles A [Albuquerque, NM; Trowbridge, Frank R [Albuquerque, NM

    2011-05-10

    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.

  4. Wafer-level packaged RF-MEMS switches fabricated in a CMOS fab

    NARCIS (Netherlands)

    Tilmans, H.A.C.; Ziad, H.; Jansen, Henricus V.; Di Monaco, O.; Jourdain, A.; De Raedt, W.; Rottenberg, X.; De Backer, E.; Decoussernaeker, A.; Baert, K.

    2001-01-01

    Reports on wafer-level packaged RF-MEMS switches fabricated in a commercial CMOS fab. Switch fabrication is based on a metal surface micromachining process. A novel wafer-level packaging scheme is developed, whereby the switches are housed in on-chip sealed cavities using benzocyclobutene (BCB) as

  5. Design and Fabrication of 1 × 2 Nanophotonic Switch

    Directory of Open Access Journals (Sweden)

    Asaf Shahmoon

    2010-01-01

    Full Text Available We present the design and the fabrication of a novel 1×2 nanophotonic switch. The switch is a photonic T-junction in which a gold nano particle is being positioned in the junction using the tip of an atomic force microscope (AFM. The novelty of this 1×2 switch is related to its ability to control the direction of wave that propagates along a photonic structure. The selectivity of the direction is determined by a gold nanoparticle having dimension of a few tens of nanometer. This particle can be shifted. The shift of the gold nano particle can be achieved by applying voltage or by illuminating it with a light source. The shifts of the particle, inside the air gap, direct the input beam ones to the left output of the junction and once to its right output. Three types of simulations have been done in order to realize the photonic T-junction, and they are as follows: photonic crystal structures, waveguide made out of PMMA, and a silicon waveguide.

  6. Switching Fabric Based on Multi-Level LVDS Compatible Interconnect, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Switching fabric (SF) is the key component of the next generation of back plane interconnects. Low power, TID and SEU resistant and high bandwidth upgradeable...

  7. Tailoring design and fabrication of capacitive RF MEMS switches for K-band applications

    Science.gov (United States)

    Quaranta, Fabio; Persano, Anna; Capoccia, Giovanni; Taurino, Antonietta; Cola, Adriano; Siciliano, Pietro; Lucibello, Andrea; Marcelli, Romolo; Proietti, Emanuela; Bagolini, Alvise; Margesin, Benno; Bellutti, Pierluigi; Iannacci, Jacopo

    2015-05-01

    Shunt capacitive radio-frequency microelectromechanical (RF MEMS) switches were modelled, fabricated and characterized in the K-band domain. Design allowed to predict the RF behaviour of the switches as a function of the bridge geometric parameters. The modelled switches were fabricated on silicon substrate, using a surface micromachining approach. In addition to the geometric parameters, the material structure in the bridge-actuator area was modified for switches fabricated on the same wafer, thanks to the removal/addition of two technological steps of crucial importance for RF MEMS switches performance, which are the use of the sacrificial layer and the deposition of a floating metal layer on the actuator. Surface profilometry analysis was used to check the material layer structure in the different regions of the bridge area as well as to investigate the mechanical behaviour of the moveable bridge under the application of a loaded force. The RF behaviour of all the fabricated switches was measured, observing the impact on the isolation of the manipulation of the bridge size and of the variations in the fabrication process.

  8. Fabrication of a Micromachined Capacitive Switch Using the CMOS-MEMS Technology

    Directory of Open Access Journals (Sweden)

    Cheng-Yang Lin

    2015-11-01

    Full Text Available The study investigates the design and fabrication of a micromachined radio frequency (RF capacitive switch using the complementary metal oxide semiconductor-microelectromechanical system (CMOS-MEMS technology. The structure of the micromachined switch is composed of a membrane, eight springs, four inductors, and coplanar waveguide (CPW lines. In order to reduce the actuation voltage of the switch, the springs are designed as low stiffness. The finite element method (FEM software CoventorWare is used to simulate the actuation voltage and displacement of the switch. The micromachined switch needs a post-CMOS process to release the springs and membrane. A wet etching is employed to etch the sacrificial silicon dioxide layer, and to release the membrane and springs of the switch. Experiments show that the pull-in voltage of the switch is 12 V. The switch has an insertion loss of 0.8 dB at 36 GHz and an isolation of 19 dB at 36 GHz.

  9. Thermoresponsive PNIPAAm-modified cotton fabric surfaces that switch between superhydrophilicity and superhydrophobicity

    International Nuclear Information System (INIS)

    Jiang Cheng; Wang Qihua; Wang Tingmei

    2012-01-01

    Thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) was grafted onto the cotton fabric by atom transfer radical polymerization (ATRP). Introducing 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFDTS) onto the surface, the density of PNIPAAm chains can be adjusted because of the competitive reactions of (3-aminopropyl) triethoxysilane (APS) and PFDTS. With the appropriate ratio of APS and PFDTS, the cotton fabric can be switched from superhydrophilic to superhydrophobic by controlling temperature. The prepared cotton fabric may find application in functional textiles, soft and folding superhydrophobic materials.

  10. Novel magnetic wire fabrication process by way of nanoimprint lithography for current induced magnetization switching

    Directory of Open Access Journals (Sweden)

    Tsukasa Asari

    2017-05-01

    Full Text Available Nanoimprint lithography (NIL is an effective method to fabricate nanowire because it does not need expensive systems and this process is easier than conventional processes. In this letter, we report the Current Induced Magnetization Switching (CIMS in perpendicularly magnetized Tb-Co alloy nanowire fabricated by NIL. The CIMS in Tb-Co alloy wire was observed by using current pulse under in-plane external magnetic field (HL. We successfully observed the CIMS in Tb-Co wire fabricated by NIL. Additionally, we found that the critical current density (Jc for the CIMS in the Tb-Co wire fabricated by NIL is 4 times smaller than that fabricated by conventional lift-off process under HL = 200Oe. These results indicate that the NIL is effective method for the CIMS.

  11. Novel magnetic wire fabrication process by way of nanoimprint lithography for current induced magnetization switching

    Science.gov (United States)

    Asari, Tsukasa; Shibata, Ryosuke; Awano, Hiroyuki

    2017-05-01

    Nanoimprint lithography (NIL) is an effective method to fabricate nanowire because it does not need expensive systems and this process is easier than conventional processes. In this letter, we report the Current Induced Magnetization Switching (CIMS) in perpendicularly magnetized Tb-Co alloy nanowire fabricated by NIL. The CIMS in Tb-Co alloy wire was observed by using current pulse under in-plane external magnetic field (HL). We successfully observed the CIMS in Tb-Co wire fabricated by NIL. Additionally, we found that the critical current density (Jc) for the CIMS in the Tb-Co wire fabricated by NIL is 4 times smaller than that fabricated by conventional lift-off process under HL = 200Oe. These results indicate that the NIL is effective method for the CIMS.

  12. Conductance switching in Ag(2)S devices fabricated by in situ sulfurization.

    Science.gov (United States)

    Morales-Masis, M; van der Molen, S J; Fu, W T; Hesselberth, M B; van Ruitenbeek, J M

    2009-03-04

    We report a simple and reproducible method to fabricate switchable Ag(2)S devices. The alpha-Ag(2)S thin films are produced by a sulfurization process after silver deposition on an Si substrate. Structure and composition of the Ag(2)S are characterized using XRD and RBS. Our samples show semiconductor behaviour at low bias voltages, whereas they exhibit reproducible bipolar resistance switching at higher bias voltages. The transition between both types of behaviour is observed by hysteresis in the I-V curves, indicating decomposition of the Ag(2)S, increasing the Ag(+) ion mobility. The as-fabricated Ag(2)S samples are a good candidate for future solid state memory devices, as they show reproducible memory resistive properties and they are fabricated by an accessible and reliable method.

  13. Conductance switching in Ag2S devices fabricated by in situ sulfurization

    International Nuclear Information System (INIS)

    Morales-Masis, M; Molen, S J van der; Hesselberth, M B; Ruitenbeek, J M van; Fu, W T

    2009-01-01

    We report a simple and reproducible method to fabricate switchable Ag 2 S devices. The α-Ag 2 S thin films are produced by a sulfurization process after silver deposition on an Si substrate. Structure and composition of the Ag 2 S are characterized using XRD and RBS. Our samples show semiconductor behaviour at low bias voltages, whereas they exhibit reproducible bipolar resistance switching at higher bias voltages. The transition between both types of behaviour is observed by hysteresis in the I-V curves, indicating decomposition of the Ag 2 S, increasing the Ag + ion mobility. The as-fabricated Ag 2 S samples are a good candidate for future solid state memory devices, as they show reproducible memory resistive properties and they are fabricated by an accessible and reliable method.

  14. Conductance switching in Ag{sub 2}S devices fabricated by in situ sulfurization

    Energy Technology Data Exchange (ETDEWEB)

    Morales-Masis, M; Molen, S J van der; Hesselberth, M B; Ruitenbeek, J M van [Kamerlingh Onnes Laboratorium, Universiteit Leiden, PO Box 9504, 2300 RA Leiden (Netherlands); Fu, W T [Leiden Institute of Chemistry, Gorlaeus Laboratorium, Universiteit Leiden, PO Box 9502, 2300 RA Leiden (Netherlands)], E-mail: ruitenbeek@physics.leidenuniv.nl

    2009-03-04

    We report a simple and reproducible method to fabricate switchable Ag{sub 2}S devices. The {alpha}-Ag{sub 2}S thin films are produced by a sulfurization process after silver deposition on an Si substrate. Structure and composition of the Ag{sub 2}S are characterized using XRD and RBS. Our samples show semiconductor behaviour at low bias voltages, whereas they exhibit reproducible bipolar resistance switching at higher bias voltages. The transition between both types of behaviour is observed by hysteresis in the I-V curves, indicating decomposition of the Ag{sub 2}S, increasing the Ag{sup +} ion mobility. The as-fabricated Ag{sub 2}S samples are a good candidate for future solid state memory devices, as they show reproducible memory resistive properties and they are fabricated by an accessible and reliable method.

  15. An asynchronous data-driven event-building scheme based on ATM switching fabrics

    International Nuclear Information System (INIS)

    Letheren, M.; Christiansen, J.; Mandjavidze, I.; Verhille, H.; De Prycker, M.; Pauwels, B.; Petit, G.; Wright, S.; Lumley, J.

    1994-01-01

    The very high data rates expected in experiments at the next generation of high luminosity hadron colliders will be handled by pipelined front-end readout electronics and multiple levels (2 or 3) of triggering. A variety of data acquisition architectures have been proposed for use downstream of the first level trigger. Depending on the architecture, the aggregate bandwidths required for event building are expected to be of the order 10--100 Gbit/s. Here, an Asynchronous Transfer Mode (ATM) packet-switching network technology is proposed as the interconnect for building high-performance, scalable data acquisition architectures. This paper introduces the relevant characteristics of ATM and describes components for the construction of an ATM-based event builder: (1) a multi-path, self-routing, scalable ATM switching fabric, (2) an experimental high performance workstation ATM-interface, and (3) a VMEbus ATM-interface. The requirement for traffic shaping in ATM-based event-builders is discussed and an analysis of the performance of several such schemes is presented

  16. Fabrication of Nano-Crossbar Resistive Switching Memory Based on the Copper-Tantalum Pentoxide-Platinum Device Structure

    Science.gov (United States)

    Olga Gneri, Paula; Jardim, Marcos

    Resistive switching memory has been of interest lately not only for its simple metal-insulator-metal (MIM) structure but also for its promising ease of scalability an integration into current CMOS technologies like the Field Programmable Gate Arrays and other non-volatile memory applications. There are several resistive switching MIM combinations but under this scope of research, attention will be paid to the bipolar resistive switching characteristics and fabrication of Tantalum Pentaoxide sandwiched between platinum and copper. By changing the polarity of the voltage bias, this metal-insulator-metal (MIM) device can be switched between a high resistive state (OFF) and low resistive state (ON). The change in states is induced by an electrochemical metallization process, which causes a formation or dissolution of Cu metal filamentary paths in the Tantalum Pentaoxide insulator. There is very little thorough experimental information about the Cu-Ta 2O5-Pt switching characteristics when scaled to nanometer dimensions. In this light, the MIM structure was fabricated in a two-dimensional crossbar format. Also, with the limited available resources, a multi-spacer technique was formulated to localize the active device area in this MIM configuration to less than 20nm. This step is important in understanding the switching characteristics and reliability of this structure when scaled to nanometer dimensions.

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

    International Nuclear Information System (INIS)

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

    2017-01-01

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

  18. Design, simulation and fabrication of a novel contact-enhanced MEMS inertial switch with a movable contact point

    International Nuclear Information System (INIS)

    Cai Haogang; Ding Guifu; Yang Zhuoqing; Su Zhijuan; Zhou Jiansheng; Wang Hong

    2008-01-01

    A novel inertial switch based on a micro-electro-mechanical system (MEMS) was designed, which consists of three main parts: a proof mass as the movable electrode, a cross beam as the stationary electrode and a movable contact point to prolong the contact time. A MATLAB/Simulink model, which had been verified by comparison with ANSYS transient simulation, was built to simulate the dynamic response, based on which the contact-enhancing mechanism was confirmed and the dependence of threshold acceleration on the proof mass thickness was studied. The simulated dynamic responses under various accelerations exhibit satisfactory device behaviors: the switch-on time is prolonged under transient acceleration; the switch-on state is more continuous than the conventional design under long lasting acceleration. The inertial micro-switch was fabricated by multilayer electroplating technology and then tested by a drop hammer experiment. The test results indicate that the contact effect was improved significantly and a steady switch-on time of over 50 µs was observed under half-sine wave acceleration with 1 ms duration, in agreement with the dynamic simulation

  19. Macro-mechanics controls quantum mechanics: mechanically controllable quantum conductance switching of an electrochemically fabricated atomic-scale point contact.

    Science.gov (United States)

    Staiger, Torben; Wertz, Florian; Xie, Fangqing; Heinze, Marcel; Schmieder, Philipp; Lutzweiler, Christian; Schimmel, Thomas

    2018-01-12

    Here, we present a silver atomic-scale device fabricated and operated by a combined technique of electrochemical control (EC) and mechanically controllable break junction (MCBJ). With this EC-MCBJ technique, we can perform mechanically controllable bistable quantum conductance switching of a silver quantum point contact (QPC) in an electrochemical environment at room temperature. Furthermore, the silver QPC of the device can be controlled both mechanically and electrochemically, and the operating mode can be changed from 'electrochemical' to 'mechanical', which expands the operating mode for controlling QPCs. These experimental results offer the perspective that a silver QPC may be used as a contact for a nanoelectromechanical relay.

  20. Macro-mechanics controls quantum mechanics: mechanically controllable quantum conductance switching of an electrochemically fabricated atomic-scale point contact

    Science.gov (United States)

    Staiger, Torben; Wertz, Florian; Xie, Fangqing; Heinze, Marcel; Schmieder, Philipp; Lutzweiler, Christian; Schimmel, Thomas

    2018-01-01

    Here, we present a silver atomic-scale device fabricated and operated by a combined technique of electrochemical control (EC) and mechanically controllable break junction (MCBJ). With this EC-MCBJ technique, we can perform mechanically controllable bistable quantum conductance switching of a silver quantum point contact (QPC) in an electrochemical environment at room temperature. Furthermore, the silver QPC of the device can be controlled both mechanically and electrochemically, and the operating mode can be changed from ‘electrochemical’ to ‘mechanical’, which expands the operating mode for controlling QPCs. These experimental results offer the perspective that a silver QPC may be used as a contact for a nanoelectromechanical relay.

  1. Semiconductor-Free Nonvolatile Resistive Switching Memory Devices Based on Metal Nanogaps Fabricated on Flexible Substrates via Adhesion Lithography

    KAUST Repository

    Semple, James

    2017-01-02

    Electronic memory cells are of critical importance in modern-day computing devices, including emerging technology sectors such as large-area printed electronics. One technology that has being receiving significant interest in recent years is resistive switching primarily due to its low dimensionality and nonvolatility. Here, we describe the development of resistive switching memory device arrays based on empty aluminum nanogap electrodes. By employing adhesion lithography, a low-temperature and large-area compatible nanogap fabrication technique, dense arrays of memory devices are demonstrated on both rigid and flexible plastic substrates. As-prepared devices exhibit nonvolatile memory operation with stable endurance, resistance ratios >10⁴ and retention times of several months. An intermittent analysis of the electrode microstructure reveals that controlled resistive switching is due to migration of metal from the electrodes into the nanogap under the application of an external electric field. This alternative form of resistive random access memory is promising for use in emerging sectors such as large-area electronics as well as in electronics for harsh environments, e.g., space, high/low temperature, magnetic influences, radiation, vibration, and pressure.

  2. Semiconductor-Free Nonvolatile Resistive Switching Memory Devices Based on Metal Nanogaps Fabricated on Flexible Substrates via Adhesion Lithography

    KAUST Repository

    Semple, James; Wyatt-Moon, Gwenhivir; Georgiadou, Dimitra G.; McLachlan, Martyn A.; Anthopoulos, Thomas D.

    2017-01-01

    Electronic memory cells are of critical importance in modern-day computing devices, including emerging technology sectors such as large-area printed electronics. One technology that has being receiving significant interest in recent years is resistive switching primarily due to its low dimensionality and nonvolatility. Here, we describe the development of resistive switching memory device arrays based on empty aluminum nanogap electrodes. By employing adhesion lithography, a low-temperature and large-area compatible nanogap fabrication technique, dense arrays of memory devices are demonstrated on both rigid and flexible plastic substrates. As-prepared devices exhibit nonvolatile memory operation with stable endurance, resistance ratios >10⁴ and retention times of several months. An intermittent analysis of the electrode microstructure reveals that controlled resistive switching is due to migration of metal from the electrodes into the nanogap under the application of an external electric field. This alternative form of resistive random access memory is promising for use in emerging sectors such as large-area electronics as well as in electronics for harsh environments, e.g., space, high/low temperature, magnetic influences, radiation, vibration, and pressure.

  3. Fabrication of high crystalline SnS and SnS2 thin films, and their switching device characteristics

    Science.gov (United States)

    Choi, Hyeongsu; Lee, Jeongsu; Shin, Seokyoon; Lee, Juhyun; Lee, Seungjin; Park, Hyunwoo; Kwon, Sejin; Lee, Namgue; Bang, Minwook; Lee, Seung-Beck; Jeon, Hyeongtag

    2018-05-01

    Representative tin sulfide compounds, tin monosulfide (SnS) and tin disulfide (SnS2) are strong candidates for future nanoelectronic devices, based on non-toxicity, low cost, unique structures and optoelectronic properties. However, it is insufficient for synthesizing of tin sulfide thin films using vapor phase deposition method which is capable of fabricating reproducible device and securing high quality films, and their device characteristics. In this study, we obtained highly crystalline SnS thin films by atomic layer deposition and obtained highly crystalline SnS2 thin films by phase transition of the SnS thin films. The SnS thin film was transformed into SnS2 thin film by annealing at 450 °C for 1 h in H2S atmosphere. This phase transition was confirmed by x-ray diffractometer and x-ray photoelectron spectroscopy, and we studied the cause of the phase transition. We then compared the film characteristics of these two tin sulfide thin films and their switching device characteristics. SnS and SnS2 thin films had optical bandgaps of 1.35 and 2.70 eV, and absorption coefficients of about 105 and 104 cm‑1 in the visible region, respectively. In addition, SnS and SnS2 thin films exhibited p-type and n-type semiconductor characteristics. In the images of high resolution-transmission electron microscopy, SnS and SnS2 directly showed a highly crystalline orthorhombic and hexagonal layered structure. The field effect transistors of SnS and SnS2 thin films exhibited on–off drain current ratios of 8.8 and 2.1 × 103 and mobilities of 0.21 and 0.014 cm2 V‑1 s‑1, respectively. This difference in switching device characteristics mainly depends on the carrier concentration because it contributes to off-state conductance and mobility. The major carrier concentrations of the SnS and SnS2 thin films were 6.0 × 1016 and 8.7 × 1013 cm‑3, respectively, in this experiment.

  4. Low-cost fabrication and polar-dependent switching uniformity of memory devices using alumina interfacial layer and Ag nanoparticle monolayer

    Directory of Open Access Journals (Sweden)

    Peng Xia

    2017-11-01

    Full Text Available A facile and low-cost process was developed for fabricating write-once-read-many-times (WORM Cu/Ag NPs/Alumina/Al memory devices, where the alumina passivation layer formed naturally in air at room temperature, whereas the Ag nanoparticle monolayer was in situ prepared through thermal annealing of a 4.5 nm Ag film in air at 150°C. The devices exhibit irreversible transition from initial high resistance (OFF state to low resistance (ON state, with ON/OFF ratio of 107, indicating the introduction of Ag nanoparticle monolayer greatly improves ON/OFF ratio by four orders of magnitude. The uniformity of threshold voltages exhibits a polar-dependent behavior, and a narrow range of threshold voltages of 0.40 V among individual devices was achieved upon the forward voltage. The memory device can be regarded as two switching units connected in series. The uniform alumina interfacial layer and the non-uniform distribution of local electric fields originated from Ag nanoparticles might be responsible for excellent switching uniformity. Since silver ions in active layer can act as fast ion conductor, a plausible mechanism relating to the formation of filaments sequentially among the two switching units connected in series is suggested for the polar-dependent switching behavior. Furthermore, we demonstrate both alumina layer and Ag NPs monolayer play essential roles in improving switching parameters based on comparative experiments.

  5. Low-cost fabrication and polar-dependent switching uniformity of memory devices using alumina interfacial layer and Ag nanoparticle monolayer

    Science.gov (United States)

    Xia, Peng; Li, Luman; Wang, Pengfei; Gan, Ying; Xu, Wei

    2017-11-01

    A facile and low-cost process was developed for fabricating write-once-read-many-times (WORM) Cu/Ag NPs/Alumina/Al memory devices, where the alumina passivation layer formed naturally in air at room temperature, whereas the Ag nanoparticle monolayer was in situ prepared through thermal annealing of a 4.5 nm Ag film in air at 150°C. The devices exhibit irreversible transition from initial high resistance (OFF) state to low resistance (ON) state, with ON/OFF ratio of 107, indicating the introduction of Ag nanoparticle monolayer greatly improves ON/OFF ratio by four orders of magnitude. The uniformity of threshold voltages exhibits a polar-dependent behavior, and a narrow range of threshold voltages of 0.40 V among individual devices was achieved upon the forward voltage. The memory device can be regarded as two switching units connected in series. The uniform alumina interfacial layer and the non-uniform distribution of local electric fields originated from Ag nanoparticles might be responsible for excellent switching uniformity. Since silver ions in active layer can act as fast ion conductor, a plausible mechanism relating to the formation of filaments sequentially among the two switching units connected in series is suggested for the polar-dependent switching behavior. Furthermore, we demonstrate both alumina layer and Ag NPs monolayer play essential roles in improving switching parameters based on comparative experiments.

  6. Fabrication of graphene-nanoflake/poly(4-vinylphenol) polymer nanocomposite thin film by electrohydrodynamic atomization and its application as flexible resistive switching device

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Kyung Hyun; Ali, Junaid [Department of Mechatronics Engineering, Jeju National University, Jeju 690-756 (Korea, Republic of); Na, Kyoung-Hoan, E-mail: khna@dankook.ac.kr [College of Engineering, Dankook University, Yongin-si, Gyeonggi-do 448-701 (Korea, Republic of)

    2015-10-15

    This paper describes synthesis of graphene/poly(4-vinylphenol) (PVP) nanocomposite and deposition of thin film by electrohydrodynamic atomization (EHDA) for fabrication flexible resistive switching device. EHDA technique proved its viability for thin film deposition after surface morphology analyses by field emission scanning electron microscope (FESEM) and non-destructive 3D Nano-profilometry, as the deposited films were, devoid of abnormalities. The commercially available graphene micro-flakes were exfoliated and broken down to ultra-small (20 nm–200 nm) nano-flakes by ultra-sonication in presence of N-methyl-pyrrolidone (NMP). These graphene nanoflakes with PVP nanocomposite, were successfully deposited as thin films (thickness ~140±7 nm, R{sub a}=2.59 nm) on indium–tin-oxide (ITO) coated polyethylene terephthalate (PET) substrate. Transmittance data revealed that thin films are up to ~87% transparent in visible and NIR region. Resistive switching behaviour of graphene/PVP nanocomposite thin film was studied by using the nanocomposite as active layer in Ag/active layer/ITO sandwich structure. The resistive switching devices thus fabricated, showed characteristic OFF to ON (high resistance to low resistance) transition at low voltages, when operated between ±3 V, characterized at 10 nA compliance currents. The devices fabricated by this approach exhibited a stable room temperature, low power current–voltage hysteresis and well over 1 h retentivity, and R{sub OFF}/R{sub ON}≈35:1. The device showed stable flexibility up to a minimum bending diameter of 1.8 cm.

  7. Effect of laser beam conditioning on fabrication of clean micro-channel on stainless steel 316L using second harmonic of Q-switched Nd:YAG laser

    Science.gov (United States)

    Singh, Sanasam Sunderlal; Baruah, Prahlad Kr; Khare, Alika; Joshi, Shrikrishna N.

    2018-02-01

    Laser micromachining of metals for fabrication of micro-channels generate ridge formation along the edges accompanied by ripples along the channel bed. The ridge formation is due to the formation of interference pattern formed by back reflections from the beam splitter and other optical components involved before focusing on the work piece. This problem can be curtailed by using a suitable aperture or Iris diaphragm so as to cut the unwanted portion of the laser beam before illuminating the sample. This paper reports an experimental investigation on minimizing this problem by conditioning the laser beam using an Iris diaphragm and using optimum process parameters. In this work, systematic experiments have been carried out using the second harmonic of a Q-switched Nd:YAG laser to fabricate micro-channels. Initial experiments revealed that formation of ridges along the sides of micro-channel can easily be minimized with the help of Iris diaphragm. Further it is noted that a clean micro-channel of depth 43.39 μm, width up to 64.49 μm and of good surface quality with average surface roughness (Ra) value of 370 nm can be machined on stainless steel (SS) 316L by employing optimum process condition: laser beam energy of 30 mJ/pulse, 11 number of laser scans and scan speed of 169.54 μm/s with an opening of 4 mm diameter of Iris diaphragm in the path of the laser beam.

  8. Resistive switching of Cu/Cu2O junction fabricated using simple thermal oxidation at 423 K for memristor application

    Science.gov (United States)

    Ani, M. H.; Helmi, F.; Herman, S. H.; Noh, S.

    2018-01-01

    Recently, extensive researches have been done on memristor to replace current memory storage technologies. Study on active layer of memristor mostly involving n-type semiconductor oxide such as TiO2 and ZnO. This paper highlight a simple water vapour oxidation method at 423 K to form Cu/Cu2O electronic junction as a new type of memristor. Cu2O is a p-type semiconductor oxide, was used as the active layer of memristor. Cu/Cu2O/Au memristor was fabricated by thermal oxidation of copper foil, followed by sputtering of gold. Structural, morphological and memristive properties were characterized using XRD, FESEM, and current-voltage, I-V measurement respectively. Its memristivity was indentified by pinch hysteresis loop and measurement of high resistance state (HRS) and low resistance state (LRS) of the sample. The Cu/Cu2O/Au memristor demonstrates comparable performances to previous studies using other methods.

  9. Coherent 40 Gb/s SP-16QAM and 80 Gb/s PDM-16QAM in an Optimal Supercomputer Optical Switch Fabric

    DEFF Research Database (Denmark)

    Karinou, Fotini; Borkowski, Robert; Zibar, Darko

    2013-01-01

    We demonstrate, for the first time, the feasibility of using 40 Gb/s SP-16QAM and 80 Gb/s PDM-16QAM in an optimized cell switching supercomputer optical interconnect architecture based on semiconductor optical amplifiers as ON/OFF gates.......We demonstrate, for the first time, the feasibility of using 40 Gb/s SP-16QAM and 80 Gb/s PDM-16QAM in an optimized cell switching supercomputer optical interconnect architecture based on semiconductor optical amplifiers as ON/OFF gates....

  10. A sustainable and green process for scouring of cotton fabrics using xylano-pectinolytic synergism: switching from noxious chemicals to eco-friendly catalysts.

    Science.gov (United States)

    Singh, Avtar; Kaur, Amanjot; Patra, Arun Kumar; Mahajan, Ritu

    2018-04-01

    The objective of this research was to develop an appropriate, eco-friendly, cost-effective bioscouring methodology for removing natural impurities from cotton fabric. Maximum bioscouring was achieved using 5.0 IU xylanase and 4.0 IU pectinase with material to liquid ratio of 1:15 in a 50 mM buffer (glycine-NaOH buffer, 1.0 mM EDTA and 1% Tween-80, pH 8.5) with a treatment time of 60 min at 50 °C and an agitation speed of 60 rpm. The bioscoured cotton fabrics showed a gain of 1.17% in whiteness, 3.23% in brightness and a reduction of 4.18% in yellowness in comparison to fabric scoured with an alkaline scouring method. Further, after bleaching, the whiteness, brightness and tensile strength of the bioscoured fabrics were increased by 2.18, 2.33 and 11.74% along with a decrease of 4.61% in yellowness of bioscoured plus bleached fabrics in comparison to chemically scoured plus bleached fabrics. From the results, it is clear that bioscouring is more efficient, energy saving and an eco-friendly process and has the potential to replace the environment-damaging scouring process with the xylano-pectinolytic bioscouring process.

  11. Amorphous metal based nanoelectromechanical switch

    KAUST Repository

    Mayet, Abdulilah M.; Smith, Casey; Hussain, Muhammad Mustafa

    2013-01-01

    Nanoelectromechanical (NEM) switch is an interesting ultra-low power option which can operate in the harsh environment and can be a complementary element in complex digital circuitry. Although significant advancement is happening in this field, report on ultra-low voltage (pull-in) switch which offers high switching speed and area efficiency is yet to be made. One key challenge to achieve such characteristics is to fabricate nano-scale switches with amorphous metal so the shape and dimensional integrity are maintained to achieve the desired performance. Therefore, we report a tungsten alloy based amorphous metal with fabrication process development of laterally actuated dual gated NEM switches with 100 nm width and 200 nm air-gap to result in <5 volts of actuation voltage (Vpull-in). © 2013 IEEE.

  12. Amorphous metal based nanoelectromechanical switch

    KAUST Repository

    Mayet, Abdulilah M.

    2013-04-01

    Nanoelectromechanical (NEM) switch is an interesting ultra-low power option which can operate in the harsh environment and can be a complementary element in complex digital circuitry. Although significant advancement is happening in this field, report on ultra-low voltage (pull-in) switch which offers high switching speed and area efficiency is yet to be made. One key challenge to achieve such characteristics is to fabricate nano-scale switches with amorphous metal so the shape and dimensional integrity are maintained to achieve the desired performance. Therefore, we report a tungsten alloy based amorphous metal with fabrication process development of laterally actuated dual gated NEM switches with 100 nm width and 200 nm air-gap to result in <5 volts of actuation voltage (Vpull-in). © 2013 IEEE.

  13. Exciter switch

    Science.gov (United States)

    Mcpeak, W. L.

    1975-01-01

    A new exciter switch assembly has been installed at the three DSN 64-m deep space stations. This assembly provides for switching Block III and Block IV exciters to either the high-power or 20-kW transmitters in either dual-carrier or single-carrier mode. In the dual-carrier mode, it provides for balancing the two drive signals from a single control panel located in the transmitter local control and remote control consoles. In addition to the improved switching capabilities, extensive monitoring of both the exciter switch assembly and Transmitter Subsystem is provided by the exciter switch monitor and display assemblies.

  14. Pseudospark switches

    International Nuclear Information System (INIS)

    Billault, P.; Riege, H.; Gulik, M. van; Boggasch, E.; Frank, K.

    1987-01-01

    The pseudospark discharge is bound to a geometrical structure which is particularly well suited for switching high currents and voltages at high power levels. This type of discharge offers the potential for improvement in essentially all areas of switching operation: peak current and current density, current rise, stand-off voltage, reverse current capability, cathode life, and forward drop. The first pseudospark switch was built at CERN at 1981. Since then, the basic switching characteristics of pseudospark chambers have been studied in detail. The main feature of a pseudospark switch is the confinement of the discharge plasma to the device axis. The current transition to the hollow electrodes is spread over a rather large surface area. Another essential feature is the easy and precise triggering of the pseudospark switch from the interior of the hollow electrodes, relatively far from the main discharge gap. Nanosecond delay and jitter values can be achieved with trigger energies of less than 0.1 mJ, although cathode heating is not required. Pseudospark gaps may cover a wide range of high-voltage, high-current, and high-pulse-power switching at repetition rates of many kilohertz. This report reviews the basic researh on pseudospark switches which has been going on at CERN. So far, applications have been developed in the range of thyratron-like medium-power switches at typically 20 to 40 kV and 0.5 to 10 kA. High-current pseudospark switches have been built for a high-power 20 kJ pulse generator which is being used for long-term tests of plasma lenses developed for the future CERN Antiproton Collector (ACOL). The high-current switches have operated for several hundred thousand shots, with 20 to 50 ns jitter at 16 kV charging voltage and more than 100 kA peak current amplitude. (orig.)

  15. Bipolar resistive switching in different plant and animal proteins

    KAUST Repository

    Bag, A.; Hota, Mrinal Kanti; Mallik, Sandipan B.; Maì ti, Chinmay Kumar

    2014-01-01

    We report bipolar resistive switching phenomena observed in different types of plant and animal proteins. Using protein as the switching medium, resistive switching devices have been fabricated with conducting indium tin oxide (ITO) and Al as bottom and top electrodes, respectively. A clockwise bipolar resistive switching phenomenon is observed in all proteins. It is shown that the resistive switching phenomena originate from the local redox process in the protein and the ion exchange from the top electrode/protein interface.

  16. Bipolar resistive switching in different plant and animal proteins

    KAUST Repository

    Bag, A.

    2014-06-01

    We report bipolar resistive switching phenomena observed in different types of plant and animal proteins. Using protein as the switching medium, resistive switching devices have been fabricated with conducting indium tin oxide (ITO) and Al as bottom and top electrodes, respectively. A clockwise bipolar resistive switching phenomenon is observed in all proteins. It is shown that the resistive switching phenomena originate from the local redox process in the protein and the ion exchange from the top electrode/protein interface.

  17. Diffusion pipes at PNP switching transistors

    International Nuclear Information System (INIS)

    Sachelarie, D.; Postolache, C.; Gaiseanu, F.

    1976-01-01

    The appearance of the ''diffusion pipes'' greatly affects the fabrication of the PNP high-frequency/very-fast-switching transistors. A brief review of the principal problems connected to the presence of these ''pipes'' is made. A research program is presented which permitted the fabrication of the PNP switching transistors at ICCE-Bucharest, with transition frequency fsub(T) = 1.2 GHz and storage time tsub(s) = 4.5 ns. (author)

  18. Microelectromechanical Switches for Phased Array Antennas

    Science.gov (United States)

    Ponchak, George E.; Simons, Rainee N.; Scardelletti, Maximillian; Varaljay, Nicholas C.

    2000-01-01

    Preliminary results are presented on the fabrication and testing of a MicroElectro-Mechanical (MEM) microstrip series switch. This switch is being developed for use in a K-band phased array antenna that NASA will use for communication links in its Earth orbiting satellites. Preliminary insertion loss and isolation measurements are presented.

  19. Scalable optical switches for computing applications

    NARCIS (Netherlands)

    White, I.H.; Aw, E.T.; Williams, K.A.; Wang, Haibo; Wonfor, A.; Penty, R.V.

    2009-01-01

    A scalable photonic interconnection network architecture is proposed whereby a Clos network is populated with broadcast-and-select stages. This enables the efficient exploitation of an emerging class of photonic integrated switch fabric. A low distortion space switch technology based on recently

  20. Switching Phenomena

    Science.gov (United States)

    Stanley, H. E.; Buldyrev, S. V.; Franzese, G.; Havlin, S.; Mallamace, F.; Mazza, M. G.; Kumar, P.; Plerou, V.; Preis, T.; Stokely, K.; Xu, L.

    One challenge of biology, medicine, and economics is that the systems treated by these serious scientific disciplines can suddenly "switch" from one behavior to another, even though they possess no perfect metronome in time. As if by magic, out of nothing but randomness one finds remarkably fine-tuned processes in time. The past century has, philosophically, been concerned with placing aside the human tendency to see the universe as a fine-tuned machine. Here we will address the challenge of uncovering how, through randomness (albeit, as we shall see, strongly correlated randomness), one can arrive at some of the many temporal patterns in physics, economics, and medicine and even begin to characterize the switching phenomena that enable a system to pass from one state to another. We discuss some applications of correlated randomness to understanding switching phenomena in various fields. Specifically, we present evidence from experiments and from computer simulations supporting the hypothesis that water's anomalies are related to a switching point (which is not unlike the "tipping point" immortalized by Malcolm Gladwell), and that the bubbles in economic phenomena that occur on all scales are not "outliers" (another Gladwell immortalization).

  1. Neuromorphic atomic switch networks.

    Directory of Open Access Journals (Sweden)

    Audrius V Avizienis

    Full Text Available Efforts to emulate the formidable information processing capabilities of the brain through neuromorphic engineering have been bolstered by recent progress in the fabrication of nonlinear, nanoscale circuit elements that exhibit synapse-like operational characteristics. However, conventional fabrication techniques are unable to efficiently generate structures with the highly complex interconnectivity found in biological neuronal networks. Here we demonstrate the physical realization of a self-assembled neuromorphic device which implements basic concepts of systems neuroscience through a hardware-based platform comprised of over a billion interconnected atomic-switch inorganic synapses embedded in a complex network of silver nanowires. Observations of network activation and passive harmonic generation demonstrate a collective response to input stimulus in agreement with recent theoretical predictions. Further, emergent behaviors unique to the complex network of atomic switches and akin to brain function are observed, namely spatially distributed memory, recurrent dynamics and the activation of feedforward subnetworks. These devices display the functional characteristics required for implementing unconventional, biologically and neurally inspired computational methodologies in a synthetic experimental system.

  2. Manufacture of Radio Frequency Micromachined Switches with Annealing

    OpenAIRE

    Lin, Cheng-Yang; Dai, Ching-Liang

    2014-01-01

    The fabrication and characterization of a radio frequency (RF) micromachined switch with annealing were presented. The structure of the RF switch consists of a membrane, coplanar waveguide (CPW) lines, and eight springs. The RF switch is manufactured using the complementary metal oxide semiconductor (CMOS) process. The switch requires a post-process to release the membrane and springs. The post-process uses a wet etching to remove the sacrificial silicon dioxide layer, and to obtain the suspe...

  3. Compact integrated optical devices for optical sensor and switching applications

    NARCIS (Netherlands)

    Kauppinen, L.J.

    2010-01-01

    This thesis describes the design, fabrication, and characterization of compact optical devices for sensing and switching applications. Our focus has been to realize the devices using CMOS-compatible fabrication processes. Particularly the silicon photonics fabrication platform, ePIXfab, has been

  4. Surface effects of electrode-dependent switching behavior of resistive random-access memory

    KAUST Repository

    Ke, Jr Jian; Wei, Tzu Chiao; Tsai, Dung Sheng; Lin, Chun-Ho; He, Jr-Hau

    2016-01-01

    of the oxygen chemisorption process was proposed to explain this electrode-dependent switching behavior. The temperature-dependent switching voltage demonstrates that the ReRAM devices fabricated with Pt electrodes have a lower activation energy

  5. Stabilization of a Nb3Sn persistent current switch

    International Nuclear Information System (INIS)

    Urata, M.; Maeda, H.; Nakayama, S.; Yoneda, E.; Oda, Y.; Kumano, T.; Aoki, N.; Tomisaki, T.; Kabashima, S.

    1993-01-01

    A 2000 A class Nb 3 Sn persistent current switch has been successfully fabricated in the Toshiba R and D Center. The Nb tube processed conductor with Cu-10 wt.% Ni matrix has been developed for the switch in the Showa Electric Wire and Cable Co. Ltd. The magnetic instability which was observed in the previous 35 Ω Nb 3 Sn persistent current switch was improved in the present switch. The problem of quench current degradation and flux jump on magnetization, emerged in the previous switch, were confirmed to be solved. In the fast ramp, however, the switch degrades from the calculated results assuming the self field ac loss. In the Nb 3 Sn reaction process, Sn in the bronze diffuses into the Nb tube, which decreases the switch resistance. It was observed by a computer aided micro analysis (CMA) that Ni in the CuNi matrix precipitated on the Nb tube, which slightly reduced the switch resistance. (orig.)

  6. Switched on!

    CERN Multimedia

    2008-01-01

    Like a star arriving on stage, impatiently followed by each member of CERN personnel and by millions of eyes around the world, the first beam of protons has circulated in the LHC. After years in the making and months of increasing anticipation, today the work of hundreds of people has borne fruit. WELL DONE to all! Successfully steered around the 27 kilometres of the world’s most powerful particle accelerator at 10:28 this morning, this first beam of protons circulating in the ring marks a key moment in the transition from over two decades of preparation to a new era of scientific discovery. "It’s a fantastic moment," said the LHC project leader Lyn Evans, "we can now look forward to a new era of understanding about the origins and evolution of the universe". Starting up a major new particle accelerator takes much more than flipping a switch. Thousands of individual elements have to work in harmony, timings have to be synchronize...

  7. The operational mechanism of ferroelectric-driven organic resistive switches

    NARCIS (Netherlands)

    Kemerink, M.; Asadi, K.; Blom, P.W.M.; Leeuw, D.M. de

    2012-01-01

    The availability of a reliable memory element is crucial for the fabrication of 'plastic' logic circuits. We use numerical simulations to show that the switching mechanism of ferroelectric-driven organic resistive switches is the stray field of the polarized ferroelectric phase. The stray field

  8. The operational mechanism of ferroelectric-driven organic resistive switches

    NARCIS (Netherlands)

    Kemerink, M.; Asadi, K. (Kamal); Blom, P.W.M.; Leeuw, de D.M.

    2012-01-01

    The availability of a reliable memory element is crucial for the fabrication of ‘plastic’ logic circuits. We use numerical simulations to show that the switching mechanism of ferroelectric-driven organic resistive switches is the stray field of the polarized ferroelectric phase. The stray field

  9. The operational mechanism of ferroelectric-driven organic resistive switches

    NARCIS (Netherlands)

    Kemerink, Martijn; Asadi, Kamal; Blom, Paul W. M.; de Leeuw, Dago M.

    The availability of a reliable memory element is crucial for the fabrication of 'plastic' logic circuits. We use numerical simulations to show that the switching mechanism of ferroelectric-driven organic resistive switches is the stray field of the polarized ferroelectric phase. The stray field

  10. Digital switched hydraulics

    Science.gov (United States)

    Pan, Min; Plummer, Andrew

    2018-06-01

    This paper reviews recent developments in digital switched hydraulics particularly the switched inertance hydraulic systems (SIHSs). The performance of SIHSs is presented in brief with a discussion of several possible configurations and control strategies. The soft switching technology and high-speed switching valve design techniques are discussed. Challenges and recommendations are given based on the current research achievements.

  11. Fast and low power Michelson interferometer thermo-optical switch on SOI.

    Science.gov (United States)

    Song, Junfeng; Fang, Q; Tao, S H; Liow, T Y; Yu, M B; Lo, G Q; Kwong, D L

    2008-09-29

    We designed and fabricated silicon-on-insulator based Michelson interferometer (MI) thermo-optical switches with deep etched trenches for heat-isolation. Switch power was reduced approximately 20% for the switch with deep etched trenches, and the MI saved approximately 50% power than that of the Mach-Zehnder interferometer. 10.6 mW switch power, approximately 42 micros switch time for the MI with deep trenches, 13.14 mW switch power and approximately 34 micros switch time for the MI without deep trenches were achieved.

  12. Fabrication Facilities

    Data.gov (United States)

    Federal Laboratory Consortium — The Fabrication Facilities are a direct result of years of testing support. Through years of experience, the three fabrication facilities (Fort Hood, Fort Lewis, and...

  13. Performance evaluation of 100 Gigabit ethernet switching system

    DEFF Research Database (Denmark)

    Rytlig, Andreas; Ruepp, Sarah Renée; Manolova, Anna Vasileva

    2010-01-01

    100 Gigabit Ethernet is an emerging technology and to support it, existing switch fabrics need to be redesigned. High throughput and QoS are required. A scalable multi-stage fabric based on a Clos architecture is envisaged to meet these demands. Using OPNET modeler, a design based on a variation...

  14. Latching micro optical switch

    Science.gov (United States)

    Garcia, Ernest J; Polosky, Marc A

    2013-05-21

    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.

  15. Performance Evaluation of 100 Gigabit Ethernet Switches under Bursty Traffic

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Rytlig, A.; Manolova, Anna Vasileva

    2011-01-01

    Switch fabrics for 100 Gigabit Ethernet systems pose high demands in terms of delay and scalability. In this paper we analyze the performance of a Clos-based switch fabric under uniform and bursty traffic, and compare its performance to a crossbar-based switch design for benchmarking. In particular......, we focus on a Clos-design using a Space-Memory-Memory (SMM) configuration, which has recently gained increased interest due to its reduced hardware complexity. The traffic between the input and the central modules is distributed in either a static, random or Desynchronized Static Round Robin (DSRR...... switch only reveals a minor performance penalty, which can be compensated by the high scalability, robustness and low complexity of the Clos-based design for high speed switching systems....

  16. Using MEMS Capacitive Switches in Tunable RF Amplifiers

    OpenAIRE

    Danson John; Plett Calvin; Tait Niall

    2006-01-01

    A MEMS capacitive switch suitable for use in tunable RF amplifiers is described. A MEMS switch is designed, fabricated, and characterized with physical and RF measurements for inclusion in simulations. Using the MEMS switch models, a dual-band low-noise amplifier (LNA) operating at GHz and GHz, and a tunable power amplifier (PA) at GHz are simulated in m CMOS. MEMS switches allow the LNA to operate with 11 dB of isolation between the two bands while maintaining dB of gain and sub- dB no...

  17. Call for Papers: Photonics in Switching

    Science.gov (United States)

    Wosinska, Lena; Glick, Madeleine

    2006-04-01

    Call for Papers: Photonics in Switching Guest Editors: Lena Wosinska, Royal Institute of Technology (KTH) / ICT Sweden Madeleine Glick, Intel Research, Cambridge, UK Technologies based on DWDM systems allow data transmission with bit rates of Tbit/s on a single fiber. To facilitate this enormous transmission volume, high-capacity and high-speed network nodes become inevitable in the optical network. Wideband switching, WDM switching, optical burst switching (OBS), and optical packet switching (OPS) are promising technologies for harnessing the bandwidth of WDM optical fiber networks in a highly flexible and efficient manner. As a number of key optical component technologies approach maturity, photonics in switching is becoming an increasingly attractive and practical solution for the next-generation of optical networks. The scope of this special issue is focused on the technology and architecture of optical switching nodes, including the architectural and algorithmic aspects of high-speed optical networks. Scope of Submission The scope of the papers includes, but is not limited to, the following topics: WDM node architectures Novel device technologies enabling photonics in switching, such as optical switch fabrics, optical memory, and wavelength conversion Routing protocols WDM switching and routing Quality of service Performance measurement and evaluation Next-generation optical networks: architecture, signaling, and control Traffic measurement and field trials Optical burst and packet switching OBS/OPS node architectures Burst/Packet scheduling and routing algorithms Contention resolution/avoidance strategies Services and applications for OBS/OPS (e.g., grid networks, storage-area networks, etc.) Burst assembly and ingress traffic shaping Hybrid OBS/TDM or OBS/wavelength routing Manuscript Submission To submit to this special issue, follow the normal procedure for submission to JON and select ``Photonics in Switching' in the features indicator of the online

  18. Microwave pulse generation by photoconductive switching

    Energy Technology Data Exchange (ETDEWEB)

    Pocha, M.D.; Druce, R.L.

    1989-03-14

    Laser activated photoconductive semiconductor switching shows significant potential for application in high power microwave generation. Primary advantages of this concept are: small size, light weight, ruggedness, precise timing and phasing by optical control, and the potential for high peak power in short pulses. Several concepts have been suggested for microwave generation using this technology. They generally fall into two categories (1) the frozen wave generator or (2) tuned cavity modulation, both of which require only fast closing switches. We have been exploring a third possibility requiring fast closing and opening switches, that is the direct modulation of the switch at microwave frequencies. Switches have been fabricated at LLNL using neutron irradiated Gallium Arsenide which exhibit response times as short as 50 ps at low voltages. We are in the process of performing high voltage tests. So far, we have been able to generate 2.4 kV pulses with approximately 340 ps response time (FWHM) using approximately a 200..mu..J optical pulse. Experiments are continuing to increase the voltage and improve the switching efficiency. 3 refs., 6 figs.

  19. Microwave pulse generation by photoconductive switching

    Science.gov (United States)

    Pocha, M. D.; Druce, R. L.

    1989-03-01

    Laser activated photoconductive semiconductor switching shows significant potential for application in high power microwave generation. Primary advantages of this concept are: small size, light weight, ruggedness, precise timing and phasing by optical control, and the potential for high peak power in short pulses. Several concepts have been suggested for microwave generation using this technology. They generally fall into two categories: (1) the frozen wave generator, or (2) tuned cavity modulation, both of which require only fast closing switches. We have been exploring a third possibility requiring fast closing and opening switches, that is the direct modulation of the switch at microwave frequencies. Switches have been fabricated at LLNL using neutron irradiated Gallium Arsenide which exhibit response times as short as 50 ps at low voltages. We are in the process of performing high voltage tests. So far, we have been able to generate 2.4 kV pulses with approximately 340 ps response time (FWHM) using approximately a 200 microJ optical pulse. Experiments are continuing to increase the voltage and improve the switching efficiency.

  20. Manufacture of Radio Frequency Micromachined Switches with Annealing

    Directory of Open Access Journals (Sweden)

    Cheng-Yang Lin

    2014-01-01

    Full Text Available The fabrication and characterization of a radio frequency (RF micromachined switch with annealing were presented. The structure of the RF switch consists of a membrane, coplanar waveguide (CPW lines, and eight springs. The RF switch is manufactured using the complementary metal oxide semiconductor (CMOS process. The switch requires a post-process to release the membrane and springs. The post-process uses a wet etching to remove the sacrificial silicon dioxide layer, and to obtain the suspended structures of the switch. In order to improve the residual stress of the switch, an annealing process is applied to the switch, and the membrane obtains an excellent flatness. The finite element method (FEM software CoventorWare is utilized to simulate the stress and displacement of the RF switch. Experimental results show that the RF switch has an insertion loss of 0.9 dB at 35 GHz and an isolation of 21 dB at 39 GHz. The actuation voltage of the switch is 14 V.

  1. Manufacture of radio frequency micromachined switches with annealing.

    Science.gov (United States)

    Lin, Cheng-Yang; Dai, Ching-Liang

    2014-01-17

    The fabrication and characterization of a radio frequency (RF) micromachined switch with annealing were presented. The structure of the RF switch consists of a membrane, coplanar waveguide (CPW) lines, and eight springs. The RF switch is manufactured using the complementary metal oxide semiconductor (CMOS) process. The switch requires a post-process to release the membrane and springs. The post-process uses a wet etching to remove the sacrificial silicon dioxide layer, and to obtain the suspended structures of the switch. In order to improve the residual stress of the switch, an annealing process is applied to the switch, and the membrane obtains an excellent flatness. The finite element method (FEM) software CoventorWare is utilized to simulate the stress and displacement of the RF switch. Experimental results show that the RF switch has an insertion loss of 0.9 dB at 35 GHz and an isolation of 21 dB at 39 GHz. The actuation voltage of the switch is 14 V.

  2. Optical packet switched networks

    DEFF Research Database (Denmark)

    Hansen, Peter Bukhave

    1999-01-01

    Optical packet switched networks are investigated with emphasis on the performance of the packet switch blocks. Initially, the network context of the optical packet switched network is described showing that a packet network will provide transparency, flexibility and bridge the granularity gap...... in interferometric wavelength converters is investigated showing that a 10 Gbit/s 19 4x4 swich blocks can be cascaded at a BER of 10-14. An analytical traffic model enables the calculation of the traffice performance of a WDM packet network. Hereby the importance of WDM and wavelegth conversion in the switch blocks...... is established as a flexible means to reduce the optical buffer, e.g., the number of fibre delay lines for a 16x16 switch block is reduced from 23 to 6 by going from 2 to 8 wavelength channels pr. inlet. Additionally, a component count analysis is carried out to illustrate the trade-offs in the switch block...

  3. Saturated Switching Systems

    CERN Document Server

    Benzaouia, Abdellah

    2012-01-01

    Saturated Switching Systems treats the problem of actuator saturation, inherent in all dynamical systems by using two approaches: positive invariance in which the controller is designed to work within a region of non-saturating linear behaviour; and saturation technique which allows saturation but guarantees asymptotic stability. The results obtained are extended from the linear systems in which they were first developed to switching systems with uncertainties, 2D switching systems, switching systems with Markovian jumping and switching systems of the Takagi-Sugeno type. The text represents a thoroughly referenced distillation of results obtained in this field during the last decade. The selected tool for analysis and design of stabilizing controllers is based on multiple Lyapunov functions and linear matrix inequalities. All the results are illustrated with numerical examples and figures many of them being modelled using MATLAB®. Saturated Switching Systems will be of interest to academic researchers in con...

  4. Effective switching frequency multiplier inverter

    Science.gov (United States)

    Su, Gui-Jia [Oak Ridge, TN; Peng, Fang Z [Okemos, MI

    2007-08-07

    A switching frequency multiplier inverter for low inductance machines that uses parallel connection of switches and each switch is independently controlled according to a pulse width modulation scheme. The effective switching frequency is multiplied by the number of switches connected in parallel while each individual switch operates within its limit of switching frequency. This technique can also be used for other power converters such as DC/DC, AC/DC converters.

  5. Digital fabrication

    CERN Document Server

    2012-01-01

    The Winter 2012 (vol. 14 no. 3) issue of the Nexus Network Journal features seven original papers dedicated to the theme “Digital Fabrication”. Digital fabrication is changing architecture in fundamental ways in every phase, from concept to artifact. Projects growing out of research in digital fabrication are dependent on software that is entirely surface-oriented in its underlying mathematics. Decisions made during design, prototyping, fabrication and assembly rely on codes, scripts, parameters, operating systems and software, creating the need for teams with multidisciplinary expertise and different skills, from IT to architecture, design, material engineering, and mathematics, among others The papers grew out of a Lisbon symposium hosted by the ISCTE-Instituto Universitario de Lisboa entitled “Digital Fabrication – A State of the Art”. The issue is completed with four other research papers which address different mathematical instruments applied to architecture, including geometric tracing system...

  6. FreeSWITCH Cookbook

    CERN Document Server

    Minessale, Anthony

    2012-01-01

    This is a problem-solution approach to take your FreeSWITCH skills to the next level, where everything is explained in a practical way. If you are a system administrator, hobbyist, or someone who uses FreeSWITCH on a regular basis, this book is for you. Whether you are a FreeSWITCH expert or just getting started, this book will take your skills to the next level.

  7. Elements of magnetic switching

    International Nuclear Information System (INIS)

    Aaland, K.

    1983-01-01

    This chapter describes magnetic switching as a method of connecting a capacitor bank (source) to a load; reviews several successful applications of magnetic switching, and discusses switching transformers, limitations and future possibilities. Some of the inflexibility and especially the high cost of magnetic materials may be overcome with the availability of the new splash cooled ribbons (Metglas). Experience has shown that magnetics works despite shock, radiation or noise interferences

  8. Pemodelan Markov Switching Autoregressive

    OpenAIRE

    Ariyani, Fiqria Devi; Warsito, Budi; Yasin, Hasbi

    2014-01-01

    Transition from depreciation to appreciation of exchange rate is one of regime switching that ignored by classic time series model, such as ARIMA, ARCH, or GARCH. Therefore, economic variables are modeled by Markov Switching Autoregressive (MSAR) which consider the regime switching. MLE is not applicable to parameters estimation because regime is an unobservable variable. So that filtering and smoothing process are applied to see the regime probabilities of observation. Using this model, tran...

  9. An electromagnetically actuated fiber optic switch using magnetized ferromagnetic materials

    Science.gov (United States)

    Pandojirao-S, Praveen; Dhaubanjar, Naresh; Phuyal, Pratibha C.; Chiao, Mu; Chiao, J.-C.

    2008-03-01

    This paper presents the design, fabrication and testing of a fiber optic switch actuated electromagnetically. The ferromagnetic gel coated optical fiber is actuated using external electromagnetic fields. The ferromagnetic gel consists of ferromagnetic powders dispersed in epoxy. The fabrication utilizes a simple cost-effective coating setup. A direct fiberto-fiber alignment eliminates the need for complementary optical parts and the displacement of fiber switches the laser coupling. The magnetic characteristics of magnetized ferromagnetic materials are performed using alternating gradient magnetometer and the magnetic hysteresis curves are measured for different ferromagnetic materials including iron, cobalt, and nickel. Optical fiber switches with various fiber lengths are actuated and their static and dynamic responses for the same volume of ferromagnetic gel are summarized. The highest displacement is 1.345 mm with an input current of 260mA. In this paper, the performance of fiber switches with various coating materials is presented.

  10. Transient-Switch-Signal Suppressor

    Science.gov (United States)

    Bozeman, Richard J., Jr.

    1995-01-01

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

  11. Optimal switching using coherent control

    DEFF Research Database (Denmark)

    Kristensen, Philip Trøst; Heuck, Mikkel; Mørk, Jesper

    2013-01-01

    that the switching time, in general, is not limited by the cavity lifetime. Therefore, the total energy required for switching is a more relevant figure of merit than the switching speed, and for a particular two-pulse switching scheme we use calculus of variations to optimize the switching in terms of input energy....

  12. Switched reluctance motor drives

    Indian Academy of Sciences (India)

    Davis RM, Ray WF, Blake RJ 1981 Inverter drive for switched reluctance: circuits and component ratings. Inst. Elec. Eng. Proc. B128: 126-136. Ehsani M. 1991 Position Sensor elimination technique for the switched reluctance motor drive. US Patent No. 5,072,166. Ehsani M, Ramani K R 1993 Direct control strategies based ...

  13. Manually operated coded switch

    International Nuclear Information System (INIS)

    Barnette, J.H.

    1978-01-01

    The disclosure related to a manually operated recodable coded switch in which a code may be inserted, tried and used to actuate a lever controlling an external device. After attempting a code, the switch's code wheels must be returned to their zero positions before another try is made

  14. Switch on, switch off: stiction in nanoelectromechanical switches

    KAUST Repository

    Wagner, Till J W

    2013-06-13

    We present a theoretical investigation of stiction in nanoscale electromechanical contact switches. We develop a mathematical model to describe the deflection of a cantilever beam in response to both electrostatic and van der Waals forces. Particular focus is given to the question of whether adhesive van der Waals forces cause the cantilever to remain in the \\'ON\\' state even when the electrostatic forces are removed. In contrast to previous studies, our theory accounts for deflections with large slopes (i.e. geometrically nonlinear). We solve the resulting equations numerically to study how a cantilever beam adheres to a rigid electrode: transitions between \\'free\\', \\'pinned\\' and \\'clamped\\' states are shown to be discontinuous and to exhibit significant hysteresis. Our findings are compared to previous results from linearized models and the implications for nanoelectromechanical cantilever switch design are discussed. © 2013 IOP Publishing Ltd.

  15. Avalanche photoconductive switching

    Science.gov (United States)

    Pocha, M. D.; Druce, R. L.; Wilson, M. J.; Hofer, W. W.

    This paper describes work being done at Lawrence Livermore National Laboratory on the avalanche mode of operation of laser triggered photoconductive switches. We have been able to generate pulses with amplitudes of 2 kV to 35 kV and rise times of 300 to 500 ps, and with a switching gain (energy of output electrical pulse vs energy of trigger optical pulse) of 10(exp 3) to over 10(exp 5). Switches with two very different physical configurations and with two different illumination wavelengths (1.06 micrometer, 890 nm) exhibit very similar behavior. The avalanche switching behavior, therefore, appears to be related to the material parameters rather than the optical wavelength or switch geometry. Considerable further work needs to be done to fully characterize and understand this mode of operation.

  16. Avalanche photoconductive switching

    Energy Technology Data Exchange (ETDEWEB)

    Pocha, M.D.; Druce, R.L.; Wilson, M.J.; Hofer, W.W.

    1989-01-01

    This paper describes work being done at Lawrence Livermore National Laboratory on the avalanche mode of operation of laser triggered photoconductive switches. We have been able to generate pulses with amplitudes of 2 kV--35 kV and rise times of 300--500 ps, and with a switching gain (energy of output electrical pulse vs energy of trigger optical pulse) of 10{sup 3} to over 10{sup 5}. Switches with two very different physical configurations and with two different illumination wavelengths (1.06 {mu}m, 890 nm) exhibit very similar behavior. The avalanche switching behavior, therefore, appears to be related to the material parameters rather than the optical wavelength or switch geometry. Considerable further work needs to be done to fully characterize and understand this mode of operation. 3 refs., 6 figs.

  17. Using MEMS Capacitive Switches in Tunable RF Amplifiers

    Directory of Open Access Journals (Sweden)

    Danson John

    2006-01-01

    Full Text Available A MEMS capacitive switch suitable for use in tunable RF amplifiers is described. A MEMS switch is designed, fabricated, and characterized with physical and RF measurements for inclusion in simulations. Using the MEMS switch models, a dual-band low-noise amplifier (LNA operating at GHz and GHz, and a tunable power amplifier (PA at GHz are simulated in m CMOS. MEMS switches allow the LNA to operate with 11 dB of isolation between the two bands while maintaining dB of gain and sub- dB noise figure. MEMS switches are used to implement a variable matching network that allows the PA to realize up to 37% PAE improvement at low input powers.

  18. Energy losses in switches

    International Nuclear Information System (INIS)

    Martin, T.H.; Seamen, J.F.; Jobe, D.O.

    1993-01-01

    The authors experiments show energy losses between 2 and 10 times that of the resistive time predictions. The experiments used hydrogen, helium, air, nitrogen, SF 6 polyethylene, and water for the switching dielectric. Previously underestimated switch losses have caused over predicting the accelerator outputs. Accurate estimation of these losses is now necessary for new high-efficiency pulsed power devices where the switching losses constitute the major portion of the total energy loss. They found that the switch energy losses scale as (V peak I peak ) 1.1846 . When using this scaling, the energy losses in any of the tested dielectrics are almost the same. This relationship is valid for several orders of magnitude and suggested a theoretical basis for these results. Currents up to .65 MA, with voltages to 3 MV were applied to various gaps during these experiments. The authors data and the developed theory indicates that the switch power loss continues for a much longer time than the resistive time, with peak power loss generally occurring at peak current in a ranging discharge instead of the early current time. All of the experiments were circuit code modeled after developing a new switch loss version based on the theory. The circuit code predicts switch energy loss and peak currents as a function of time. During analysis of the data they noticed slight constant offsets between the theory and data that depended on the dielectric. They modified the plasma conductivity for each tested dielectric to lessen this offset

  19. A low-latency optical switch architecture using integrated μm SOI-based contention resolution and switching

    Science.gov (United States)

    Mourgias-Alexandris, G.; Moralis-Pegios, M.; Terzenidis, N.; Cherchi, M.; Harjanne, M.; Aalto, T.; Vyrsokinos, K.; Pleros, N.

    2018-02-01

    The urgent need for high-bandwidth and high-port connectivity in Data Centers has boosted the deployment of optoelectronic packet switches towards bringing high data-rate optics closer to the ASIC, realizing optical transceiver functions directly at the ASIC package for high-rate, low-energy and low-latency interconnects. Even though optics can offer a broad range of low-energy integrated switch fabrics for replacing electronic switches and seamlessly interface with the optical I/Os, the use of energy- and latency-consuming electronic SerDes continues to be a necessity, mainly dictated by the absence of integrated and reliable optical buffering solutions. SerDes undertakes the role of optimally synergizing the lower-speed electronic buffers with the incoming and outgoing optical streams, suggesting that a SerDes-released chip-scale optical switch fabric can be only realized in case all necessary functions including contention resolution and switching can be implemented on a common photonic integration platform. In this paper, we demonstrate experimentally a hybrid Broadcast-and-Select (BS) / wavelength routed optical switch that performs both the optical buffering and switching functions with μm-scale Silicon-integrated building blocks. Optical buffering is carried out in a silicon-integrated variable delay line bank with a record-high on-chip delay/footprint efficiency of 2.6ns/mm2 and up to 17.2 nsec delay capability, while switching is executed via a BS design and a silicon-integrated echelle grating, assisted by SOA-MZI wavelength conversion stages and controlled by a FPGA header processing module. The switch has been experimentally validated in a 3x3 arrangement with 10Gb/s NRZ optical data packets, demonstrating error-free switching operation with a power penalty of <5dB.

  20. Electromechanical magnetization switching

    Energy Technology Data Exchange (ETDEWEB)

    Chudnovsky, Eugene M. [Department of Physics and Astronomy, Lehman College and Graduate School, The City University of New York, 250 Bedford Park Boulevard West, Bronx, New York 10468-1589 (United States); Jaafar, Reem [Department of Mathematics, Engineering and Computer Science, LaGuardia Community College, The City University of New York, 31-10 Thomson Avenue, Long Island City, New York 11101 (United States)

    2015-03-14

    We show that the magnetization of a torsional oscillator that, in addition to the magnetic moment also possesses an electrical polarization, can be switched by the electric field that ignites mechanical oscillations at the frequency comparable to the frequency of the ferromagnetic resonance. The 180° switching arises from the spin-rotation coupling and is not prohibited by the different symmetry of the magnetic moment and the electric field as in the case of a stationary magnet. Analytical equations describing the system have been derived and investigated numerically. Phase diagrams showing the range of parameters required for the switching have been obtained.

  1. Electromechanical magnetization switching

    International Nuclear Information System (INIS)

    Chudnovsky, Eugene M.; Jaafar, Reem

    2015-01-01

    We show that the magnetization of a torsional oscillator that, in addition to the magnetic moment also possesses an electrical polarization, can be switched by the electric field that ignites mechanical oscillations at the frequency comparable to the frequency of the ferromagnetic resonance. The 180° switching arises from the spin-rotation coupling and is not prohibited by the different symmetry of the magnetic moment and the electric field as in the case of a stationary magnet. Analytical equations describing the system have been derived and investigated numerically. Phase diagrams showing the range of parameters required for the switching have been obtained

  2. JUNOS Enterprise Switching

    CERN Document Server

    Reynolds, Harry

    2009-01-01

    JUNOS Enterprise Switching is the only detailed technical book on Juniper Networks' new Ethernet-switching EX product platform. With this book, you'll learn all about the hardware and ASIC design prowess of the EX platform, as well as the JUNOS Software that powers it. Not only is this extremely practical book a useful, hands-on manual to the EX platform, it also makes an excellent study guide for certification exams in the JNTCP enterprise tracks. The authors have based JUNOS Enterprise Switching on their own Juniper training practices and programs, as well as the configuration, maintenanc

  3. Switch mode power supply

    International Nuclear Information System (INIS)

    Kim, Hui Jun

    1993-06-01

    This book concentrates on switch mode power supply. It has four parts, which are introduction of switch mode power supply with DC-DC converter such as Buck converter boost converter, Buck-boost converter and PWM control circuit, explanation for SMPS with DC-DC converter modeling and power mode control, resonance converter like resonance switch, converter, multi resonance converter and series resonance and parallel resonance converters, basic test of SMPS with PWM control circuit, Buck converter, Boost converter, flyback converter, forward converter and IC for control circuit.

  4. An absorptive single-pole four-throw switch using multiple-contact MEMS switches and its application to a monolithic millimeter-wave beam-forming network

    International Nuclear Information System (INIS)

    Lee, Sanghyo; Kim, Jong-Man; Kim, Yong-Kweon; Kwon, Youngwoo

    2009-01-01

    In this paper, a new absorptive single-pole four-throw (SP4T) switch based on multiple-contact switching is proposed and integrated with a Butler matrix to demonstrate a monolithic beam-forming network at millimeter waves (mm waves). In order to simplify the switching driving circuit and reduce the number of unit switches in an absorptive SP4T switch, the individual switches were replaced with long-span multiple-contact switches using stress-free single-crystalline-silicon MEMS technology. This approach improves the mechanical stability as well as the manufacturing yield, thereby allowing successful integration into a monolithic beam former. The fabricated absorptive SP4T MEMS switch shows insertion loss less than 1.3 dB, return losses better than 11 dB at 30 GHz and wideband isolation performance higher than 39 dB from 20 to 40 GHz. The absorptive SP4T MEMS switch is integrated with a 4 × 4 Butler matrix on a single chip to implement a monolithic beam-forming network, directing beam into four distinct angles. Array factors from the measured data show that the proposed absorptive SPnT MEMS switch can be effectively used for high-performance mm-wave beam-switching systems. This work corresponds to the first demonstration of a monolithic beam-forming network using switched beams

  5. Optical switching systems using nanostructures

    DEFF Research Database (Denmark)

    Stubkjær, Kristian

    2004-01-01

    High capacity multiservice optical networks require compact and efficient switches. The potential benefits of optical switch elements based on nanostructured material are reviewed considering various material systems.......High capacity multiservice optical networks require compact and efficient switches. The potential benefits of optical switch elements based on nanostructured material are reviewed considering various material systems....

  6. Bipolar resistive switching behaviors of ITO nanowire networks

    Directory of Open Access Journals (Sweden)

    Qiang Li

    2016-02-01

    Full Text Available We have fabricated indium tin oxide (ITO nanowire (NW networks on aluminum electrodes using electron beam evaporation. The Ag/ITO-NW networks/Al capacitor exhibits bipolar resistive switching behavior. The resistive switching characteristics of ITO-NW networks are related to the morphology of NWs. The x-ray photoelectron spectroscopy was used to obtain the chemical nature from the NWs surface, investigating the oxygen vacancy state. A stable switching voltages and a clear memory window were observed in needle-shaped NWs. The ITO-NW networks can be used as a new two-dimensional metal oxide material for the fabrication of high-density memory devices.

  7. Software-defined networking control plane for seamless integration of multiple silicon photonic switches in Datacom networks.

    Science.gov (United States)

    Shen, Yiwen; Hattink, Maarten H N; Samadi, Payman; Cheng, Qixiang; Hu, Ziyiz; Gazman, Alexander; Bergman, Keren

    2018-04-16

    Silicon photonics based switches offer an effective option for the delivery of dynamic bandwidth for future large-scale Datacom systems while maintaining scalable energy efficiency. The integration of a silicon photonics-based optical switching fabric within electronic Datacom architectures requires novel network topologies and arbitration strategies to effectively manage the active elements in the network. We present a scalable software-defined networking control plane to integrate silicon photonic based switches with conventional Ethernet or InfiniBand networks. Our software-defined control plane manages both electronic packet switches and multiple silicon photonic switches for simultaneous packet and circuit switching. We built an experimental Dragonfly network testbed with 16 electronic packet switches and 2 silicon photonic switches to evaluate our control plane. Observed latencies occupied by each step of the switching procedure demonstrate a total of 344 µs control plane latency for data-center and high performance computing platforms.

  8. Energy reversible switching from amorphous metal based nanoelectromechanical switch

    KAUST Repository

    Mayet, Abdulilah M.; Smith, Casey; Hussain, Muhammad Mustafa

    2013-01-01

    We report observation of energy reversible switching from amorphous metal based nanoelectromechanical (NEM) switch. For ultra-low power electronics, NEM switches can be used as a complementary switching element in many nanoelectronic system applications. Its inherent zero power consumption because of mechanical detachment is an attractive feature. However, its operating voltage needs to be in the realm of 1 volt or lower. Appropriate design and lower Young's modulus can contribute achieving lower operating voltage. Therefore, we have developed amorphous metal with low Young's modulus and in this paper reporting the energy reversible switching from a laterally actuated double electrode NEM switch. © 2013 IEEE.

  9. Energy reversible switching from amorphous metal based nanoelectromechanical switch

    KAUST Repository

    Mayet, Abdulilah M.

    2013-08-01

    We report observation of energy reversible switching from amorphous metal based nanoelectromechanical (NEM) switch. For ultra-low power electronics, NEM switches can be used as a complementary switching element in many nanoelectronic system applications. Its inherent zero power consumption because of mechanical detachment is an attractive feature. However, its operating voltage needs to be in the realm of 1 volt or lower. Appropriate design and lower Young\\'s modulus can contribute achieving lower operating voltage. Therefore, we have developed amorphous metal with low Young\\'s modulus and in this paper reporting the energy reversible switching from a laterally actuated double electrode NEM switch. © 2013 IEEE.

  10. 35-kV GaAs subnanosecond photoconductive switches

    Energy Technology Data Exchange (ETDEWEB)

    Pocha, M.D.; Druce, R.L. (Lawrence Livermore National Lab., CA (United States))

    1990-12-01

    Photoconductive switches are one of the few devices that allow the generation of high-voltage electrical pulses with subnanosecond rise time. The authors are exploring high-voltage, fast-pulse generation using GaAs photoconductive switches. They have been able to generate 35-kV pulses with rise times as short as 135 ps using 5-mm gap switches and have achieved electric field hold-off of greater than 100 kV/cm. They have also been able to generate an approximately 500-ps FWHM on/off electrical pulse with an amplitude of approximately 3 kV using neutron-irradiated GaAs having short carrier life times. This paper describes the experimental results and discusses fabrication of switches and the diagnostics used to measure these fast signals. They also describe the experience with the nonlinear lock-on and avalanche modes of operation observed in GaAs.

  11. Fabricated Elastin.

    Science.gov (United States)

    Yeo, Giselle C; Aghaei-Ghareh-Bolagh, Behnaz; Brackenreg, Edwin P; Hiob, Matti A; Lee, Pearl; Weiss, Anthony S

    2015-11-18

    The mechanical stability, elasticity, inherent bioactivity, and self-assembly properties of elastin make it a highly attractive candidate for the fabrication of versatile biomaterials. The ability to engineer specific peptide sequences derived from elastin allows the precise control of these physicochemical and organizational characteristics, and further broadens the diversity of elastin-based applications. Elastin and elastin-like peptides can also be modified or blended with other natural or synthetic moieties, including peptides, proteins, polysaccharides, and polymers, to augment existing capabilities or confer additional architectural and biofunctional features to compositionally pure materials. Elastin and elastin-based composites have been subjected to diverse fabrication processes, including heating, electrospinning, wet spinning, solvent casting, freeze-drying, and cross-linking, for the manufacture of particles, fibers, gels, tubes, sheets and films. The resulting materials can be tailored to possess specific strength, elasticity, morphology, topography, porosity, wettability, surface charge, and bioactivity. This extraordinary tunability of elastin-based constructs enables their use in a range of biomedical and tissue engineering applications such as targeted drug delivery, cell encapsulation, vascular repair, nerve regeneration, wound healing, and dermal, cartilage, bone, and dental replacement. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Elastomeric organic material for switching application

    Energy Technology Data Exchange (ETDEWEB)

    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)

    2014-10-15

    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.

  13. Optical computer switching network

    Science.gov (United States)

    Clymer, B.; Collins, S. A., Jr.

    1985-01-01

    The design for an optical switching system for minicomputers that uses an optical spatial light modulator such as a Hughes liquid crystal light valve is presented. The switching system is designed to connect 80 minicomputers coupled to the switching system by optical fibers. The system has two major parts: the connection system that connects the data lines by which the computers communicate via a two-dimensional optical matrix array and the control system that controls which computers are connected. The basic system, the matrix-based connecting system, and some of the optical components to be used are described. Finally, the details of the control system are given and illustrated with a discussion of timing.

  14. Flexible circuits with integrated switches for robotic shape sensing

    Science.gov (United States)

    Harnett, C. K.

    2016-05-01

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

  15. A novel multi-actuation CMOS RF MEMS switch

    Science.gov (United States)

    Lee, Chiung-I.; Ko, Chih-Hsiang; Huang, Tsun-Che

    2008-12-01

    This paper demonstrates a capacitive shunt type RF MEMS switch, which is actuated by electro-thermal actuator and electrostatic actuator at the same time, and than latching the switching status by electrostatic force only. Since thermal actuators need relative low voltage compare to electrostatic actuators, and electrostatic force needs almost no power to maintain the switching status, the benefits of the mechanism are very low actuation voltage and low power consumption. Moreover, the RF MEMS switch has considered issues for integrated circuit compatible in design phase. So the switch is fabricated by a standard 0.35um 2P4M CMOS process and uses wet etching and dry etching technologies for postprocess. This compatible ability is important because the RF characteristics are not only related to the device itself. If a packaged RF switch and a packaged IC wired together, the parasitic capacitance will cause the problem for optimization. The structure of the switch consists of a set of CPW transmission lines and a suspended membrane. The CPW lines and the membrane are in metal layers of CMOS process. Besides, the electro-thermal actuators are designed by polysilicon layer of the CMOS process. So the RF switch is only CMOS process layers needed for both electro-thermal and electrostatic actuations in switch. The thermal actuator is composed of a three-dimensional membrane and two heaters. The membrane is a stacked step structure including two metal layers in CMOS process, and heat is generated by poly silicon resistors near the anchors of membrane. Measured results show that the actuation voltage of the switch is under 7V for electro-thermal added electrostatic actuation.

  16. Study of influence on micro-fabricated resistive switching organic ...

    Indian Academy of Sciences (India)

    3Northwest Electric Power Design Institute of China Power Engineering Consulting Group, Xi'an,. Shaanxi ... gives rise to an important application of organic thin film devices as ... This C-AFM measurement system is consisted with an AFM.

  17. VXS, A High Speed Cu Switch Fabric Interconnect for VME

    National Research Council Canada - National Science Library

    Wong, Henry

    2004-01-01

    ... and keying strategy, 2X power improvements, and cooling strategies. This work was done within the context of the VSO industry standards body to promote an eco-system of developers, vendors, and users...

  18. Radiation Hardened Ethernet PHY and Switch Fabric, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Innoflight will develop a new family of radiation hardened (up to 3 Mrad(Si)), fault-tolerant, high data-rate (up to 8 Gbps), low power Gigabit Ethernet PHY and...

  19. Stochastic Switching Dynamics

    DEFF Research Database (Denmark)

    Simonsen, Maria

    This thesis treats stochastic systems with switching dynamics. Models with these characteristics are studied from several perspectives. Initially in a simple framework given in the form of stochastic differential equations and, later, in an extended form which fits into the framework of sliding...... mode control. It is investigated how to understand and interpret solutions to models of switched systems, which are exposed to discontinuous dynamics and uncertainties (primarily) in the form of white noise. The goal is to gain knowledge about the performance of the system by interpreting the solution...

  20. Very high plasma switches. Basic plasma physics and switch technology

    International Nuclear Information System (INIS)

    Doucet, H.J.; Roche, M.; Buzzi, J.M.

    1988-01-01

    A review of some high power switches recently developed for very high power technology is made with a special attention to the aspects of plasma physics involved in the mechanisms, which determine the limits of the possible switching parameters

  1. NEBULAS A High Performance Data-Driven Event-Building Architecture based on an Asynchronous Self-Routing Packet-Switching Network

    CERN Multimedia

    Costa, M; Letheren, M; Djidi, K; Gustafsson, L; Lazraq, T; Minerskjold, M; Tenhunen, H; Manabe, A; Nomachi, M; Watase, Y

    2002-01-01

    RD31 : The project is evaluating a new approach to event building for level-two and level-three processor farms at high rate experiments. It is based on the use of commercial switching fabrics to replace the traditional bus-based architectures used in most previous data acquisition sytems. Switching fabrics permit the construction of parallel, expandable, hardware-driven event builders that can deliver higher aggregate throughput than the bus-based architectures. A standard industrial switching fabric technology is being evaluated. It is based on Asynchronous Transfer Mode (ATM) packet-switching network technology. Commercial, expandable ATM switching fabrics and processor interfaces, now being developed for the future Broadband ISDN infrastructure, could form the basis of an implementation. The goals of the project are to demonstrate the viability of this approach, to evaluate the trade-offs involved in make versus buy options, to study the interfacing of the physics frontend data buffers to such a fabric, a...

  2. Modelling switching-time effects in high-frequency power conditioning networks

    Science.gov (United States)

    Owen, H. A.; Sloane, T. H.; Rimer, B. H.; Wilson, T. G.

    1979-01-01

    Power transistor networks which switch large currents in highly inductive environments are beginning to find application in the hundred kilohertz switching frequency range. Recent developments in the fabrication of metal-oxide-semiconductor field-effect transistors in the power device category have enhanced the movement toward higher switching frequencies. Models for switching devices and of the circuits in which they are imbedded are required to properly characterize the mechanisms responsible for turning on and turning off effects. Easily interpreted results in the form of oscilloscope-like plots assist in understanding the effects of parametric studies using topology oriented computer-aided analysis methods.

  3. Ultrafast gas switching experiments

    International Nuclear Information System (INIS)

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

    1993-01-01

    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 Khz at > 100 kV/m E field

  4. An integrated circuit switch

    Science.gov (United States)

    Bonin, E. L.

    1969-01-01

    Multi-chip integrated circuit switch consists of a GaAs photon-emitting diode in close proximity with S1 phototransistor. A high current gain is obtained when the transistor has a high forward common-emitter current gain.

  5. The Octopus switch

    NARCIS (Netherlands)

    Havinga, Paul J.M.

    2000-01-01

    This chapter1 discusses the interconnection architecture of the Mobile Digital Companion. The approach to build a low-power handheld multimedia computer presented here is to have autonomous, reconfigurable modules such as network, video and audio devices, interconnected by a switch rather than by a

  6. Untriggered water switching

    International Nuclear Information System (INIS)

    Van Devender, J.P.; Martin, T.H.

    Recent experiments indicate that synchronous untriggered multichannel switching in water will permit the development of relatively simple, ultra-low impedance, short pulse, relativistic electron beam (REB) accelerators. These experiments resulted in the delivery of a 1.5 MV, 0.75 MA, 15 ns pulse into a two-ohm line with a current risetime of 2 x 10 14 A/sec. The apparatus consisted of a 3 MV Marx generator and a series of three 112 cm wide strip water lines separated by two edge-plane water-gap switches. The Marx generator charged the first line in less than 400 ns. The first switch then formed five or more channels. The second line was charged in 60 ns and broke down with 10 to 25 channels at a mean field of 1.6 MV/cm. The closure time of each spark channel along both switches was measured with a streak camera and showed low jitter. The resulting fast pulse line construction is simpler and should provide considerable costs savings from previous designs. Multiples of these low impedance lines in parallel can be employed to obtain power levels in the 10 14 W range for REB fusion studies. (U.S.)

  7. Control synthesis of switched systems

    CERN Document Server

    Zhao, Xudong; Niu, Ben; Wu, Tingting

    2017-01-01

    This book offers its readers a detailed overview of the synthesis of switched systems, with a focus on switching stabilization and intelligent control. The problems investigated are not only previously unsolved theoretically but also of practical importance in many applications: voltage conversion, naval piloting and navigation and robotics, for example. The book considers general switched-system models and provides more efficient design methods to bring together theory and application more closely than was possible using classical methods. It also discusses several different classes of switched systems. For general switched linear systems and switched nonlinear systems comprising unstable subsystems, it introduces novel ideas such as invariant subspace theory and the time-scheduled Lyapunov function method of designing switching signals to stabilize the underlying systems. For some typical switched nonlinear systems affected by various complex dynamics, the book proposes novel design approaches based on inte...

  8. An Ethology of Urban Fabric(s)

    DEFF Research Database (Denmark)

    Fritsch, Jonas; Thomsen, Bodil Marie Stavning

    2014-01-01

    The article explores a non-metaphorical understanding of urban fabric(s), shifting the attention from a bird’s eye perspective to the actual, textural manifestations of a variety of urban fabric(s) to be studied in their real, processual, ecological and ethological complexity within urban life. We...... effectuate this move by bringing into resonance a range of intersecting fields that all deal with urban fabric(s) in complementary ways (interaction design and urban design activism, fashion, cultural theory, philosophy, urban computing)....

  9. Copper oxide resistive switching memory for e-textile

    Directory of Open Access Journals (Sweden)

    Jin-Woo Han

    2011-09-01

    Full Text Available A resistive switching memory suitable for integration into textiles is demonstrated on a copper wire network. Starting from copper wires, a Cu/CuxO/Pt sandwich structure is fabricated. The active oxide film is produced by simple thermal oxidation of Cu in atmospheric ambient. The devices display a resistance switching ratio of 102 between the high and low resistance states. The memory states are reversible and retained over 107 seconds, with the states remaining nondestructive after multiple read operations. The presented device on the wire network can potentially offer a memory for integration into smart textile.

  10. Reconfigurable SDM Switching Using Novel Silicon Photonic Integrated Circuit

    DEFF Research Database (Denmark)

    Ding, Yunhong; Kamchevska, Valerija; Dalgaard, Kjeld

    2016-01-01

    -division multiplexing switching using silicon photonic integrated circuit, which is fabricated on a novel silicon-oninsulator platform with buried Al mirror. The silicon photonic integrated circuit is composed of a 7x7 switch and low loss grating coupler array based multicore fiber couplers. Thanks to the Al mirror......, grating couplers with ultra-low coupling loss with optical multicore fibers is achieved. The lowest total insertion loss of the silicon integrated circuit is as low as 4.5 dB, with low crosstalk lower than -30 dB. Excellent performances in terms of low insertion loss and low crosstalk are obtained...

  11. Synchronization Between Two Different Switched Chaotic Systems By Switching Control

    Directory of Open Access Journals (Sweden)

    Du Li Ming

    2016-01-01

    Full Text Available This paper is concerned with the synchronization problem of two different switched chaotic systems, considering the general case that the master-slave switched chaotic systems have uncertainties. Two basic problems are considered: one is projective synchronization of switched chaotic systems under arbitrary switching; the other is projective synchronization of switched chaotic systems by design of switching when synchronization cannot achieved by using any subsystems alone. For the two problems, common Lyapunov function method and multiple Lyapunov function method are used respectively, an adaptive control scheme has been presented, some sufficient synchronization conditions are attainted, and the switching signal is designed. Finally, the numerical simulation is provide to show the effectiveness of our method.

  12. Laser activated superconducting switch

    International Nuclear Information System (INIS)

    Wolf, A.A.

    1976-01-01

    A superconducting switch or bistable device is described consisting of a superconductor in a cryogen maintaining a temperature just below the transition temperature, having a window of the proper optical frequency band for passing a laser beam which may impinge on the superconductor when desired. The frequency of the laser is equal to or greater than the optical absorption frequency of the superconducting material and is consistent with the ratio of the gap energy of the switch material to Planck's constant, to cause depairing of electrons, and thereby normalize the superconductor. Some embodiments comprise first and second superconducting metals. Other embodiments feature the two superconducting metals separated by a thin film insulator through which the superconducting electrons tunnel during superconductivity

  13. Optical fiber switch

    Science.gov (United States)

    Early, James W.; Lester, Charles S.

    2002-01-01

    Optical fiber switches operated by electrical activation of at least one laser light modulator through which laser light is directed into at least one polarizer are used for the sequential transport of laser light from a single laser into a plurality of optical fibers. In one embodiment of the invention, laser light from a single excitation laser is sequentially transported to a plurality of optical fibers which in turn transport the laser light to separate individual remotely located laser fuel ignitors. The invention can be operated electro-optically with no need for any mechanical or moving parts, or, alternatively, can be operated electro-mechanically. The invention can be used to switch either pulsed or continuous wave laser light.

  14. Coulomb Blockade Plasmonic Switch.

    Science.gov (United States)

    Xiang, Dao; Wu, Jian; Gordon, Reuven

    2017-04-12

    Tunnel resistance can be modulated with bias via the Coulomb blockade effect, which gives a highly nonlinear response current. Here we investigate the optical response of a metal-insulator-nanoparticle-insulator-metal structure and show switching of a plasmonic gap from insulator to conductor via Coulomb blockade. By introducing a sufficiently large charging energy in the tunnelling gap, the Coulomb blockade allows for a conductor (tunneling) to insulator (capacitor) transition. The tunnelling electrons can be delocalized over the nanocapacitor again when a high energy penalty is added with bias. We demonstrate that this has a huge impact on the plasmonic resonance of a 0.51 nm tunneling gap with ∼70% change in normalized optical loss. Because this structure has a tiny capacitance, there is potential to harness the effect for high-speed switching.

  15. Cryogenic switched MOSFET characterization

    Science.gov (United States)

    1981-01-01

    Both p channel and n channel enhancement mode MOSFETs can be readily switched on and off at temperatures as low as 2.8 K so that switch sampled readout of a VLWIR Ge:Ga focal plane is electronically possible. Noise levels as low as 100 rms electrons per sample (independent of sample rate) can be achieved using existing p channel MOSFETs, at overall rates up to 30,000 samples/second per multiplexed channel (e.g., 32 detectors at a rate of almost 1,000 frames/second). Run of the mill devices, including very low power dissipation n channel FETs would still permit noise levels of the order of 500 electrons/sample.

  16. Practical switching power supply design

    CERN Document Server

    Brown, Martin C

    1990-01-01

    Take the ""black magic"" out of switching power supplies with Practical Switching Power Supply Design! This is a comprehensive ""hands-on"" guide to the theory behind, and design of, PWM and resonant switching supplies. You'll find information on switching supply operation and selecting an appropriate topology for your application. There's extensive coverage of buck, boost, flyback, push-pull, half bridge, and full bridge regulator circuits. Special attention is given to semiconductors used in switching supplies. RFI/EMI reduction, grounding, testing, and safety standards are also deta

  17. Uncertainty quantification in capacitive RF MEMS switches

    Science.gov (United States)

    Pax, Benjamin J.

    Development of radio frequency micro electrical-mechanical systems (RF MEMS) has led to novel approaches to implement electrical circuitry. The introduction of capacitive MEMS switches, in particular, has shown promise in low-loss, low-power devices. However, the promise of MEMS switches has not yet been completely realized. RF-MEMS switches are known to fail after only a few months of operation, and nominally similar designs show wide variability in lifetime. Modeling switch operation using nominal or as-designed parameters cannot predict the statistical spread in the number of cycles to failure, and probabilistic methods are necessary. A Bayesian framework for calibration, validation and prediction offers an integrated approach to quantifying the uncertainty in predictions of MEMS switch performance. The objective of this thesis is to use the Bayesian framework to predict the creep-related deflection of the PRISM RF-MEMS switch over several thousand hours of operation. The PRISM switch used in this thesis is the focus of research at Purdue's PRISM center, and is a capacitive contacting RF-MEMS switch. It employs a fixed-fixed nickel membrane which is electrostatically actuated by applying voltage between the membrane and a pull-down electrode. Creep plays a central role in the reliability of this switch. The focus of this thesis is on the creep model, which is calibrated against experimental data measured for a frog-leg varactor fabricated and characterized at Purdue University. Creep plasticity is modeled using plate element theory with electrostatic forces being generated using either parallel plate approximations where appropriate, or solving for the full 3D potential field. For the latter, structure-electrostatics interaction is determined through immersed boundary method. A probabilistic framework using generalized polynomial chaos (gPC) is used to create surrogate models to mitigate the costly full physics simulations, and Bayesian calibration and forward

  18. Composite Material Switches

    Science.gov (United States)

    Javadi, Hamid (Inventor)

    2002-01-01

    A device to protect electronic circuitry from high voltage transients is constructed from a relatively thin piece of conductive composite sandwiched between two conductors so that conduction is through the thickness of the composite piece. The device is based on the discovery that conduction through conductive composite materials in this configuration switches to a high resistance mode when exposed to voltages above a threshold voltage.

  19. MCT/MOSFET Switch

    Science.gov (United States)

    Rippel, Wally E.

    1990-01-01

    Metal-oxide/semiconductor-controlled thyristor (MCT) and metal-oxide/semiconductor field-effect transistor (MOSFET) connected in switching circuit to obtain better performance. Offers high utilization of silicon, low forward voltage drop during "on" period of operating cycle, fast turnon and turnoff, and large turnoff safe operating area. Includes ability to operate at high temperatures, high static blocking voltage, and ease of drive.

  20. Python Switch Statement

    Directory of Open Access Journals (Sweden)

    2008-06-01

    Full Text Available The Python programming language does not have a built in switch/case control structure as found in many other high level programming languages. It is thought by some that this is a deficiency in the language, and the control structure should be added. This paper demonstrates that not only is the control structure not needed, but that the methods available in Python are more expressive than built in case statements in other high level languages.

  1. Ferroelectric switching of elastin

    Science.gov (United States)

    Liu, Yuanming; Cai, Hong-Ling; Zelisko, Matthew; Wang, Yunjie; Sun, Jinglan; Yan, Fei; Ma, Feiyue; Wang, Peiqi; Chen, Qian Nataly; Zheng, Hairong; Meng, Xiangjian; Sharma, Pradeep; Zhang, Yanhang; Li, Jiangyu

    2014-01-01

    Ferroelectricity has long been speculated to have important biological functions, although its very existence in biology has never been firmly established. Here, we present compelling evidence that elastin, the key ECM protein found in connective tissues, is ferroelectric, and we elucidate the molecular mechanism of its switching. Nanoscale piezoresponse force microscopy and macroscopic pyroelectric measurements both show that elastin retains ferroelectricity at 473 K, with polarization on the order of 1 μC/cm2, whereas coarse-grained molecular dynamics simulations predict similar polarization with a Curie temperature of 580 K, which is higher than most synthetic molecular ferroelectrics. The polarization of elastin is found to be intrinsic in tropoelastin at the monomer level, analogous to the unit cell level polarization in classical perovskite ferroelectrics, and it switches via thermally activated cooperative rotation of dipoles. Our study sheds light onto a long-standing question on ferroelectric switching in biology and establishes ferroelectricity as an important biophysical property of proteins. This is a critical first step toward resolving its physiological significance and pathological implications. PMID:24958890

  2. A novel RF MEMS switch with novel mechanical structure modeling

    International Nuclear Information System (INIS)

    Chan, K Y; Ramer, R

    2010-01-01

    A novel RF MEMS contact-type switch for RF and microwave applications is presented. The switch is designed with special mechanical structures for stiffness enhancement. A method of using dimple lines to reduce the stress sensitivity of a beam is shown with complete mathematical modeling and finite element mechanical simulation. A complete mathematical model is developed for the proposed switch. Limited fabrication resolution and non-uniformities in layer thickness and stress were taken into consideration for this design, concomitantly with the preservation of device miniaturization and functionalities. The novel mechanical modeling of the switch leads to the estimation of the actuation voltage and shows simplification from previously published analysis. The measured actuation voltage and RF performance of the novel RF MEMS switch are also reported. The switch actuated at 20 V achieved better than 22 dB return loss and less than 0.7 dB insertion loss in on state from dc–40 GHz; it provided better than 30 dB isolation in off state

  3. Production of fast switching power thyristors by proton irradiation

    International Nuclear Information System (INIS)

    Sawko, D.C.; Bartko, J.

    1983-01-01

    There are several techniques currently employed by various manufacturers in the fabrication of fast switching power thyristors. Gold doping and irradiation by electron beams are among the more common ones. In all cases, the fast switching capability results from a reduction of the minority carrier lifetime of the host material by the introduction of carrier traps or recombination centers. However, accompanying this beneficial reduction in switching speed is a deleterious increase in forward voltage drop which also results from the introduction of carrier traps. Methods which minimize the voltage drop increase as the switching speed is reduced are highly desirable. One such method would achieve this by introducing the traps or recombination centers into well defined narrow regions where they will be more effective in reducing the switching speed than in increasing the forward voltage drop. Because the proton range-energy relationship in materials is relatively well defined and the lifetime reducing displacements occur near the end of their ranges, the lifetime in silicon can be reduced where desired by the precise control of proton energy. Dual energy proton beams from a tandem Van de Graaff accelerator were used in the experiments to determine whether proton beam irradiations offer advantages over other techniques. This was the subject of the present work. The results indicate that this is the preferred technique for reproducibly and rapidly processing fast switching thyristors with superior characteristics. The experimental procedure is discussed and comparisons are made with electron and neutron irradiated thyristors

  4. First Field Trial of Optical Label-Based Switching and Packet Drop on a 477km NTON/Sprint Link

    International Nuclear Information System (INIS)

    Hernandez, V J; Pan, Z; Cao, J; Tsui, V K; Bansal, Y; Fong, S K H; Zhang, Y; Jeon, M Y; Yoo, S J B; Bodtker, B; Bond, S; Lennon, W J; Higashi, H; Lyles, B; McDonald, R

    2001-01-01

    We demonstrate the first field trial of optical label-based wavelength switching and packet drop on 476.8km of the National Transparent Optical Network. Subcarrier multiplexed labels control a switch fabric that includes a tunable wavelength converter and arrayed waveguide grating router

  5. Fabrication and Prototyping Lab

    Data.gov (United States)

    Federal Laboratory Consortium — Purpose: The Fabrication and Prototyping Lab for composite structures provides a wide variety of fabrication capabilities critical to enabling hands-on research and...

  6. Fabrication of recyclable superhydrophobic cotton fabrics

    Science.gov (United States)

    Han, Sang Wook; Park, Eun Ji; Jeong, Myung-Geun; Kim, Il Hee; Seo, Hyun Ook; Kim, Ju Hwan; Kim, Kwang-Dae; Kim, Young Dok

    2017-04-01

    Commercial cotton fabric was coated with SiO2 nanoparticles wrapped with a polydimethylsiloxane (PDMS) layer, and the resulting material surface showed a water contact angle greater than 160°. The superhydrophobic fabric showed resistance to water-soluble contaminants and maintained its original superhydrophobic properties with almost no alteration even after many times of absorption-washing cycles of oil. Moreover, superhydrophobic fabric can be used as a filter to separate oil from water. We demonstrated a simple method of fabrication of superhydrophobic fabric with potential interest for use in a variety of applications.

  7. A graphene integrated highly transparent resistive switching memory device

    Science.gov (United States)

    Dugu, Sita; Pavunny, Shojan P.; Limbu, Tej B.; Weiner, Brad R.; Morell, Gerardo; Katiyar, Ram S.

    2018-05-01

    We demonstrate the hybrid fabrication process of a graphene integrated highly transparent resistive random-access memory (TRRAM) device. The indium tin oxide (ITO)/Al2O3/graphene nonvolatile memory device possesses a high transmittance of >82% in the visible region (370-700 nm) and exhibits stable and non-symmetrical bipolar switching characteristics with considerably low set and reset voltages (ITO/Al2O3/Pt device and studied its switching characteristics for comparison and a better understanding of the ITO/Al2O3/graphene device characteristics. The conduction mechanisms in high and low resistance states were analyzed, and the observed polarity dependent resistive switching is explained based on electro-migration of oxygen ions.

  8. 35-kV GaAs subnanosecond photoconductive switches

    Science.gov (United States)

    Pocha, Michael D.; Druce, Robert L.

    1990-12-01

    High-voltage, fast-pulse generation using GaAs photoconductive switches is investigated. It is possible to to generate 35-kV pulses with risetimes as short as 135 ps using 5-mm gap switches, and electric field hold-off of greater than 100 kV/cm is achieved. An approximately 500-ps FWHM on/off electrical pulse is generated with an amplitude of approximately 3 kV using neutron-irradiated GaAs having short carrier lifetimes. Experimental results are described, and fabrication of switches and the diagnostics used to measure these fast signals are discussed. Experience with the nonlinear lock-on and avalanche modes of operation observed in GaAs is also described.

  9. A fluorescence switch based on a controllable photochromic naphthopyran group

    International Nuclear Information System (INIS)

    Chen Lizhen; Wang Guang; Zhao Xiancai

    2011-01-01

    A fluorescence switch based on photoisomerization of naphthopyran (NP) has been designed by employing 2-(pyridin-2-yl)-benzimidazole (BPI) and the naphthopyran containing two pyran rings (NP) as fluorescent dye and photochromic compound, respectively. The fluorescence switch of benzimidazole derivative can be modulated either by controlling the irradiation time of UV light or by adjusting the amount ratio of fluorescent benzimidazole derivative to photochromic naphthopyran in both solution and polymethyl methacrylate (PMMA) film. The experimental results indicated that the decrease of fluorescence intensity of benzimidazole derivative is attributed to the interaction of benzimidazole with naphthopyran. - Highlights: → Naphthopyran was first used to fabricate fluorescence switch with benzimidazole derivative. → Fluorescence intensity can be modulated by controlling the UV irradiation time. → Fluorescence intensity can be adjusted by changing the ratio of benzimidazole derivative to naphthopyran. → Decrease of fluorescence intensity is attributed to the interaction of benzimidazole derivative and naphthopyran.

  10. Multi states electromechanical switch for energy efficient parallel data processing

    KAUST Repository

    Kloub, Hussam

    2011-04-01

    We present a design, simulation results and fabrication of electromechanical switches enabling parallel data processing and multi functionality. The device is applied in logic gates AND, NOR, XNOR, and Flip-Flops. The device footprint size is 2μm by 0.5μm, and has a pull-in voltage of 5.15V which is verified by FEM simulation. © 2011 IEEE.

  11. Multi states electromechanical switch for energy efficient parallel data processing

    KAUST Repository

    Kloub, Hussam; Smith, Casey; Hussain, Muhammad Mustafa

    2011-01-01

    We present a design, simulation results and fabrication of electromechanical switches enabling parallel data processing and multi functionality. The device is applied in logic gates AND, NOR, XNOR, and Flip-Flops. The device footprint size is 2μm by 0.5μm, and has a pull-in voltage of 5.15V which is verified by FEM simulation. © 2011 IEEE.

  12. MENGAPA PERUSAHAAN MELAKUKAN AUDITOR SWITCH?

    Directory of Open Access Journals (Sweden)

    Kadek Sumadi

    2011-01-01

    Full Text Available The existence of a large number of accounting firms allowsprovides companies choices whether to stay with current firm or switchto another accounting firm. Decision of Minister of FinanceNo.423/KMK.06/2002 states that a company must switch auditor afterfive years of consecutive assignment. This is mandatory. The questionrises when a company voluntarily switches its auditor. Why does thishappen?One of the reasons is that management does not satisfy withauditor opinion, except for unqualified opinion. New management teamwould directly or indirectly encourage auditor switch to align accountingand reporting policies. Moreover an expanding company expects positivereaction when it does auditor switch. Profitability is also one reason fora company to switch auditor, for example, when a company earns moreprofit it tends to hire more credible auditor. On the other hand, when thecompany faces a financial distress, it probably would switch auditor aswell.

  13. Optimizing POF/PCF based optical switch for indoor LAN

    International Nuclear Information System (INIS)

    Bhuiyan, M M I; Rashid, M M; Ahmed, Sayem; Bhuiyan, M; Kajihara, M

    2013-01-01

    For indoor local area network (LAN) the Polymer optical fiber (POF) is mostly appropriate, because of its large core diameter and flexible material. A 1×2 optical switch for indoor LAN using POF and a shape memory alloy (SMA) coil actuator with magnetic latches was successfully fabricated and tested. To achieve switching by the movement of a POF, large displacement is necessary because the core diameter is large (e.g., 0.486mm). A SMA coil actuator is used for large displacement and a magnetic latching system is used for fixing the position of the shifted POF. The insertion loss is 0.40 to 0.50dB and crosstalk is more than 50dB without index-matching oil. Switching speed is less than 1s at a driving current of 80mA. A cycling test was performed 1.4 million times. Polymer clad fiber optical (PCF) switch also fabricated and tasted

  14. Low-Crosstalk Composite Optical Crosspoint Switches

    Science.gov (United States)

    Pan, Jing-Jong; Liang, Frank

    1993-01-01

    Composite optical switch includes two elementary optical switches in tandem, plus optical absorbers. Like elementary optical switches, composite optical switches assembled into switch matrix. Performance enhanced by increasing number of elementary switches. Advantage of concept: crosstalk reduced to acceptably low level at moderate cost of doubling number of elementary switches rather than at greater cost of tightening manufacturing tolerances and exerting more-precise control over operating conditions.

  15. Compound semiconductor optical waveguide switch

    Science.gov (United States)

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

    2003-06-10

    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.

  16. Polymorphous computing fabric

    Science.gov (United States)

    Wolinski, Christophe Czeslaw [Los Alamos, NM; Gokhale, Maya B [Los Alamos, NM; McCabe, Kevin Peter [Los Alamos, NM

    2011-01-18

    Fabric-based computing systems and methods are disclosed. A fabric-based computing system can include a polymorphous computing fabric that can be customized on a per application basis and a host processor in communication with said polymorphous computing fabric. The polymorphous computing fabric includes a cellular architecture that can be highly parameterized to enable a customized synthesis of fabric instances for a variety of enhanced application performances thereof. A global memory concept can also be included that provides the host processor random access to all variables and instructions associated with the polymorphous computing fabric.

  17. Recent developments in switching theory

    CERN Document Server

    Mukhopadhyay, Amar

    2013-01-01

    Electrical Science Series: Recent Developments in Switching Theory covers the progress in the study of the switching theory. The book discusses the simplified proof of Post's theorem on completeness of logic primitives; the role of feedback in combinational switching circuits; and the systematic procedure for the design of Lupanov decoding networks. The text also describes the classical results on counting theorems and their application to the classification of switching functions under different notions of equivalence, including linear and affine equivalences. The development of abstract har

  18. Software Switching for Data Acquisition

    CERN Multimedia

    CERN. Geneva; Malone, David

    2016-01-01

    In this talk we discuss the feasibility of replacing telecom-class routers with a topology of commodity servers acting as software switches in data acquisition. We extend the popular software switch, Open vSwitch, with a dedicated, throughput-oriented buffering mechanism. We compare the performance under heavy many-to-one congestion to typical Ethernet switches and evaluate the scalability when building larger topologies, exploiting the integration with software-defined networking technologies. Please note that David Malone will speak on behalf of Grzegorz Jereczek.

  19. ATLAS facility fabrication and assembly

    CERN Document Server

    Ballard, E O; Davis, H A; Nielsen, K E; Parker, G V; Parsons, W M

    2001-01-01

    Summary form only given. Atlas is a pulsed-power facility recently completed at Los Alamos National Laboratory to drive hydrodynamic experiments. This new generation pulsed-power machine consists of a radial array of 24, 240-kV Marx modules and transmission lines supplying current to the load region at the machine center. The transmission lines, powered by the Marx modules, consist of cable headers, load protection switches and tri-plates interfacing to the center transition section through detachable current joints. A conical power-flow-channel attaches to the transition section providing an elevated interface to attach the experimental loads for diagnostic access. Fabrication and assembly of all components for the Atlas machine was completed in August 2000. The machine has also progressed through a test phase where the Marx module/transmission line units were fired, individually, into a test load. Progression continued with eight and sixteen lines being fired. Subsequently, an overall machine test was condu...

  20. Origin of magnetic switching field distribution in bit patterned media based on pre-patterned substrates

    OpenAIRE

    Pfau , B; Günther , C.M.; Guehrs , E; Hauet , Thomas; Yang , H; Vinh , L.; Xu , X; Yaney , D; Rick , R; Eisebitt , S; Hellwig , O

    2011-01-01

    International audience; Using a combination of synchrotron radiation based magnetic imaging and high-resolution transmission electron microscopy we reveal systematic correlations between the magnetic switching field and the internal nanoscale structure of individual islands in bit patterned media fabricated by Co/Pd-multilayer deposition onto pre-patterned substrates. We find that misaligned grains at the island periphery are a common feature independent of the island switching field, while i...

  1. Electrical switching and memory phenomena observed in redox-gradient dendrimer sandwich devices

    OpenAIRE

    Li, JianChang; Blackstock, Silas C.; Szulczewski, Greg J.

    2005-01-01

    We report on the fabrication of dendrimer sandwich devices with electrical switching and memory properties. The storage media is consisted of a redox-gradient dendrimer layer sandwiched in organic barrier thin films. The dendrimer layer acts as potential well where redox-state changes and consequent electrical transitions of the embedded dendrimer molecules are expected to be effectively triggered and retained, respectively. Experimental results indicated that electrical switching could be re...

  2. Hybrid switch for resonant power converters

    Science.gov (United States)

    Lai, Jih-Sheng; Yu, Wensong

    2014-09-09

    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.

  3. LCT protective dump-switch tests

    International Nuclear Information System (INIS)

    Parsons, W.M.

    1981-01-01

    Each of the six coils in the Large Coil Task (LCT) has a separate power supply, dump resistor, and switching circuit. Each switching circuit contains five switches, two of which are redundant. The three remaining switches perform separate duties in an emergency dump situation. These three switches were tested to determine their ability to meet the LCT conditions

  4. Effect of texturing on polarization switching dynamics in ferroelectric ceramics

    Science.gov (United States)

    Zhukov, Sergey; Genenko, Yuri A.; Koruza, Jurij; Schultheiß, Jan; von Seggern, Heinz; Sakamoto, Wataru; Ichikawa, Hiroki; Murata, Tatsuro; Hayashi, Koichiro; Yogo, Toshinobu

    2016-01-01

    Highly (100),(001)-oriented (Ba0.85Ca0.15)TiO3 (BCT) lead-free piezoelectric ceramics were fabricated by the reactive templated grain growth method using a mixture of plate-like CaTiO3 and BaTiO3 particles. Piezoelectric properties of the ceramics with a high degree of texture were found to be considerably enhanced compared with the BCT ceramics with a low degree of texture. With increasing the Lotgering factor from 26% up to 94%, the piezoelectric properties develop towards the properties of a single crystal. The dynamics of polarization switching was studied over a broad time domain of 8 orders of magnitude and was found to strongly depend on the degree of orientation of the ceramics. Samples with a high degree of texture exhibited 2-3 orders of magnitude faster polarization switching, as compared with the ones with a low degree of texture. This was rationalized by means of the Inhomogeneous Field Mechanism model as a result of the narrower statistical distribution of the local electric field values in textured media, which promotes a more coherent switching process. The extracted microscopic parameters of switching revealed a decrease of the critical nucleus energy in systems with a high degree of texture providing more favorable switching conditions related to the enhanced ferroelectric properties of the textured material.

  5. Measurement of resistance switching dynamics in copper sulfide memristor structures

    Science.gov (United States)

    McCreery, Kaitlin; Olson, Matthew; Teitsworth, Stephen

    Resistance switching materials are the subject of current research in large part for their potential to enable novel computing devices and architectures such as resistance random access memories and neuromorphic chips. A common feature of memristive structures is the hysteretic switching between high and low resistance states which is induced by the application of a sufficiently large electric field. Here, we describe a relatively simple wet chemistry process to fabricate Cu2 S / Cu memristive structures with Cu2 S film thickness ranging up to 150 micron. In this case, resistance switching is believed to be mediated by electromigration of Cu ions from the Cu substrate into the Cu2 S film. Hysteretic current-voltage curves are measured and reveal switching voltages of about 0.8 Volts with a relatively large variance and independent of film thickness. In order to gain insight into the dynamics and variability of the switching process, we have measured the time-dependent current response to voltage pulses of varying height and duration with a time resolution of 1 ns. The transient response consists of a deterministic RC component as well as stochastically varying abrupt current steps that occur within a few microseconds of the pulse application.

  6. EDITORIAL: Molecular switches at surfaces Molecular switches at surfaces

    Science.gov (United States)

    Weinelt, Martin; von Oppen, Felix

    2012-10-01

    In nature, molecules exploit interaction with their environment to realize complex functionalities on the nanometer length scale. Physical, chemical and/or biological specificity is frequently achieved by the switching of molecules between microscopically different states. Paradigmatic examples are the energy production in proton pumps of bacteria or the signal conversion in human vision, which rely on switching molecules between different configurations or conformations by external stimuli. The remarkable reproducibility and unparalleled fatigue resistance of these natural processes makes it highly desirable to emulate nature and develop artificial systems with molecular functionalities. A promising avenue towards this goal is to anchor the molecular switches at surfaces, offering new pathways to control their functional properties, to apply electrical contacts, or to integrate switches into larger systems. Anchoring at surfaces allows one to access the full range from individual molecular switches to self-assembled monolayers of well-defined geometry and to customize the coupling between molecules and substrate or between adsorbed molecules. Progress in this field requires both synthesis and preparation of appropriate molecular systems and control over suitable external stimuli, such as light, heat, or electrical currents. To optimize switching and generate function, it is essential to unravel the geometric structure, the electronic properties and the dynamic interactions of the molecular switches on surfaces. This special section, Molecular Switches at Surfaces, collects 17 contributions describing different aspects of this research field. They analyze elementary processes, both in single molecules and in ensembles of molecules, which involve molecular switching and concomitant changes of optical, electronic, or magnetic properties. Two topical reviews summarize the current status, including both challenges and achievements in the field of molecular switches on

  7. Circuit switched optical networks

    DEFF Research Database (Denmark)

    Kloch, Allan

    2003-01-01

    Some of the most important components required for enabling optical networking are investigated through both experiments and modelling. These all-optical components are the wavelength converter, the regenerator and the space switch. When these devices become "off-the-shelf" products, optical cross......, it is expected that the optical solution will offer an economical benefit for hight bit rate networks. This thesis begins with a discussion of the expected impact on communications systems from the rapidly growing IP traffic, which is expected to become the dominant source for traffic. IP traffic has some...... characteristics, which are best supported by an optical network. The interest for such an optical network is exemplified by the formation of the ACTS OPEN project which aim was to investigate the feasibility of an optical network covering Europe. Part of the work presented in this thesis is carried out within...

  8. Photo-switching element

    Energy Technology Data Exchange (ETDEWEB)

    Masaki, Yuichi

    1987-10-31

    Photo-input MOS transistor (Photo-switching element) cannot give enough ON/OFF ratio but requires an auxiliary condenser for a certain type of application. In addition, PN junction of amorphous silicon is not practical because it gives high leak current resulting in low electromotive force. In this invention, a solar cell was constructed with a lower electrode consisting of a transparent electro-conducting film, a photosensitive part consisting of an amorphous Si layer of p-i-n layer construction, and an upper metal electrode consisting of Cr or Nichrome, and a thin film transistor was placed on the solar cell, and further the upper metal electrode was co-used as a gate electrode of the thin film transistor; this set-up of this invention enabled to attain an efficient photo-electric conversion of the incident light, high electromotive force of the solar cell, and the transistor with high ON/OFF ratio. (3 figs)

  9. Battery switch for downhole tools

    Science.gov (United States)

    Boling, Brian E.

    2010-02-23

    An electrical circuit for a downhole tool may include a battery, a load electrically connected to the battery, and at least one switch electrically connected in series with the battery and to the load. The at least one switch may be configured to close when a tool temperature exceeds a selected temperature.

  10. Improved switch-resistor packaging

    Science.gov (United States)

    Redmerski, R. E.

    1980-01-01

    Packaging approach makes resistors more accessible and easily identified with specific switches. Failures are repaired more quickly because of improved accessibility. Typical board includes one resistor that acts as circuit breaker, and others are positioned so that their values can be easily measured when switch is operated. Approach saves weight by using less wire and saves valuable panel space.

  11. Fiber-optical switch using cam-micromotor driven by scratch drive actuators

    Science.gov (United States)

    Kanamori, Y.; Aoki, Y.; Sasaki, M.; Hosoya, H.; Wada, A.; Hane, K.

    2005-01-01

    We fabricated a 1 × 1 fiber-optic switch using a cam-micromotor driven by scratch drive actuators (SDAs). Using the cam-micromotor, mechanical translation and precise positioning of an optical fiber were performed. An optical fiber of diameter 50 µm was bent and pushed out with a cam-mechanism driven by the SDAs fabricated by surface micromachining. The maximum rotation speed of the cam-micromotor was 7.5 rpm at a driving frequency of 1.5 kHz. The transient time of the switch to attenuate coupling efficiency less than -40 dB was around 10 ms.

  12. Multi-polar resistance switching and memory effect in copper phthalocyanine junctions

    International Nuclear Information System (INIS)

    Qiao Shi-Zhu; Kang Shi-Shou; Li Qiang; Zhong Hai; Kang Yun; Yu Shu-Yun; Han Guang-Bing; Yan Shi-Shen; Mei Liang-Mo; Qin Yu-Feng

    2014-01-01

    Copper phthalocyanine junctions, fabricated by magnetron sputtering and evaporating methods, show multi-polar (unipolar and bipolar) resistance switching and the memory effect. The multi-polar resistance switching has not been observed simultaneously in one organic material before. With both electrodes being cobalt, the unipolar resistance switching is universal. The high resistance state is switched to the low resistance state when the bias reaches the set voltage. Generally, the set voltage increases with the thickness of copper phthalocyanine and decreases with increasing dwell time of bias. Moreover, the low resistance state could be switched to the high resistance state by absorbing the phonon energy. The stability of the low resistance state could be tuned by different electrodes. In Au/copper phthalocyanine/Co system, the low resistance state is far more stable, and the bipolar resistance switching is found. Temperature dependence of electrical transport measurements demonstrates that there are no obvious differences in the electrical transport mechanism before and after the resistance switching. They fit quite well with Mott variable range hopping theory. The effect of Al 2 O 3 on the resistance switching is excluded by control experiments. The holes trapping and detrapping in copper phthalocyanine layer are responsible for the resistance switching, and the interfacial effect between electrodes and copper phthalocyanine layer affects the memory effect. (interdisciplinary physics and related areas of science and technology)

  13. Superconductivity, energy storage and switching

    International Nuclear Information System (INIS)

    Laquer, H.L.

    1974-01-01

    The phenomenon of superconductivity can contribute to the technology of energy storage and switching in two distinct ways. On one hand the zero resistivity of the superconductor can produce essentially infinite time constants so that an inductive storage system can be charged from very low power sources. On the other hand, the recovery of finite resistivity in a normal-going superconducting switch can take place in extremely short times, so that a system can be made to deliver energy at a very high power level. Topics reviewed include: physics of superconductivity, limits to switching speed of superconductors, physical and engineering properties of superconducting materials and assemblies, switching methods, load impedance considerations, refrigeration economics, limitations imposed by present day and near term technology, performance of existing and planned energy storage systems, and a comparison with some alternative methods of storing and switching energy. (U.S.)

  14. Surface effects of electrode-dependent switching behavior of resistive random-access memory

    KAUST Repository

    Ke, Jr Jian

    2016-09-26

    The surface effects of ZnO-based resistive random-access memory (ReRAM) were investigated using various electrodes. Pt electrodes were found to have better performance in terms of the device\\'s switching functionality. A thermodynamic model of the oxygen chemisorption process was proposed to explain this electrode-dependent switching behavior. The temperature-dependent switching voltage demonstrates that the ReRAM devices fabricated with Pt electrodes have a lower activation energy for the chemisorption process, resulting in a better resistive switching performance. These findings provide an in-depth understanding of electrode-dependent switching behaviors and can serve as design guidelines for future ReRAM devices.

  15. Three-terminal nanoelectromechanical switch based on tungsten nitride—an amorphous metallic material

    KAUST Repository

    Mayet, Abdulilah M.; Hussain, Aftab M.; Hussain, Muhammad Mustafa

    2015-01-01

    © 2016 IOP Publishing Ltd. Nanoelectromechanical (NEM) switches inherently have zero off-state leakage current and nearly ideal sub-threshold swing due to their mechanical nature of operation, in contrast to semiconductor switches. A challenge for NEM switches to be practical for low-power digital logic application is their relatively large operation voltage which can result in higher dynamic power consumption. Herein we report a three-terminal laterally actuated NEM switch fabricated with an amorphous metallic material: tungsten nitride (WNx). As-deposited WNx thin films have high Young's modulus (300 GPa) and reasonably high hardness (3 GPa), which are advantageous for high wear resistance. The first prototype WNx switches are demonstrated to operate with relatively low control voltage, down to 0.8 V for an air gap thickness of 150 nm.

  16. Three-terminal nanoelectromechanical switch based on tungsten nitride—an amorphous metallic material

    KAUST Repository

    Mayet, Abdulilah M.

    2015-12-04

    © 2016 IOP Publishing Ltd. Nanoelectromechanical (NEM) switches inherently have zero off-state leakage current and nearly ideal sub-threshold swing due to their mechanical nature of operation, in contrast to semiconductor switches. A challenge for NEM switches to be practical for low-power digital logic application is their relatively large operation voltage which can result in higher dynamic power consumption. Herein we report a three-terminal laterally actuated NEM switch fabricated with an amorphous metallic material: tungsten nitride (WNx). As-deposited WNx thin films have high Young\\'s modulus (300 GPa) and reasonably high hardness (3 GPa), which are advantageous for high wear resistance. The first prototype WNx switches are demonstrated to operate with relatively low control voltage, down to 0.8 V for an air gap thickness of 150 nm.

  17. Resistive switching memories in MoS{sub 2} nanosphere assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Xiao-Yong, E-mail: xxxy@yzu.edu.cn, E-mail: xcxseu@seu.edu.cn, E-mail: jghu@yzu.edu.cn [School of Physics Science and Technology, Yangzhou University, Yangzhou 225002 (China); State Key Laboratory of Bioelectronics and School of Electronic Science and Engineering, Southeast University, Nanjing 210096 (China); School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, Singapore 639798 (Singapore); Yin, Zong-You [School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, Singapore 639798 (Singapore); Xu, Chun-Xiang, E-mail: xxxy@yzu.edu.cn, E-mail: xcxseu@seu.edu.cn, E-mail: jghu@yzu.edu.cn; Dai, Jun [State Key Laboratory of Bioelectronics and School of Electronic Science and Engineering, Southeast University, Nanjing 210096 (China); Hu, Jing-Guo, E-mail: xxxy@yzu.edu.cn, E-mail: xcxseu@seu.edu.cn, E-mail: jghu@yzu.edu.cn [School of Physics Science and Technology, Yangzhou University, Yangzhou 225002 (China)

    2014-01-20

    A resistive switching memory device consisting of reduced graphene oxide and indium tin oxide as top/bottom two electrodes, separated by dielectric MoS{sub 2} nanosphere assemblies as the active interlayer, was fabricated. This device exhibits the rewritable nonvolatile resistive switching with low SET/RESET voltage (∼2 V), high ON/OFF resistance ratio (∼10{sup 4}), and superior electrical bistability, introducing a potential application in data storage field. The resistance switching mechanism was analyzed in the assumptive model of the electron tunneling across the polarized potential barriers.

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

    International Nuclear Information System (INIS)

    Ungureanu, Mariana; Llopis, Roger; Casanova, Fèlix; Hueso, Luis E.

    2014-01-01

    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

  19. Switching Phenomena in a System with No Switches

    Science.gov (United States)

    Preis, Tobias; Stanley, H. Eugene

    2010-02-01

    It is widely believed that switching phenomena require switches, but this is actually not true. For an intriguing variety of switching phenomena in nature, the underlying complex system abruptly changes from one state to another in a highly discontinuous fashion. For example, financial market fluctuations are characterized by many abrupt switchings creating increasing trends ("bubble formation") and decreasing trends ("financial collapse"). Such switching occurs on time scales ranging from macroscopic bubbles persisting for hundreds of days to microscopic bubbles persisting only for a few seconds. We analyze a database containing 13,991,275 German DAX Future transactions recorded with a time resolution of 10 msec. For comparison, a database providing 2,592,531 of all S&P500 daily closing prices is used. We ask whether these ubiquitous switching phenomena have quantifiable features independent of the time horizon studied. We find striking scale-free behavior of the volatility after each switching occurs. We interpret our findings as being consistent with time-dependent collective behavior of financial market participants. We test the possible universality of our result by performing a parallel analysis of fluctuations in transaction volume and time intervals between trades. We show that these financial market switching processes have properties similar to those of phase transitions. We suggest that the well-known catastrophic bubbles that occur on large time scales—such as the most recent financial crisis—are no outliers but single dramatic representatives caused by the switching between upward and downward trends on time scales varying over nine orders of magnitude from very large (≈102 days) down to very small (≈10 ms).

  20. DETERMINANT OF DOWNWARD AUDITOR SWITCHING

    Directory of Open Access Journals (Sweden)

    Totok Budisantoso

    2017-12-01

    Full Text Available Abstract: Determinant of Downward Auditor Switching. This study examines the factors that influence downward auditor switching in five ASEAN countries. Fixed effect logistic regression was used as analytical method. This study found that opinion shopping occurred in ASEAN, especially in distress companies. Companies with complex businesses will retain the Big Four auditors to reduce complexity and audit costs. Audit and public committees serve as guardians of auditor quality. On the other hand, shareholders failed to maintain audit quality. It indicates that there is entrenchment effect in auditor switching.

  1. Electrically switched ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Lilga, M.A. [Pacific Northwest National Lab., Richland, WA (United States); Schwartz, D.T.; Genders, D.

    1997-10-01

    A variety of waste types containing radioactive {sup 137}Cs are found throughout the DOE complex. These waste types include water in reactor cooling basins, radioactive high-level waste (HLW) in underground storage tanks, and groundwater. Safety and regulatory requirements and economics require the removal of radiocesium before these wastes can be permanently disposed of. Electrically Switched Ion Exchange (ESIX) is an approach for radioactive cesium separation that combines IX and electrochemistry to provide a selective, reversible, and economic separation method that also produces little or no secondary waste. In the ESIX process, an electroactive IX film is deposited electrochemically onto a high-surface area electrode, and ion uptake and elution are controlled directly by modulating the potential of the film. For cesium, the electroactive films under investigation are ferrocyanides, which are well known to have high selectivities for cesium in concentrated sodium solutions. When a cathode potential is applied to the film, Fe{sup +3} is reduced to the Fe{sup +2} state, and a cation must be intercalated into the film to maintain charge neutrality (i.e., Cs{sup +} is loaded). Conversely, if an anodic potential is applied, a cation must be released from the film (i.e., Cs{sup +} is unloaded). Therefore, to load the film with cesium, the film is simply reduced; to unload cesium, the film is oxidized.

  2. High current vacuum closing switch

    International Nuclear Information System (INIS)

    Dolgachev, G.I.; Maslennikov, D.D.; Romanov, A.S.; Ushakov, A.G.

    2005-01-01

    The paper proposes a powerful pulsed closing vacuum switch for high current commutation consisting of series of the vacuum diodes with near 1 mm gaps having closing time determined by the gaps shortening with the near-electrode plasmas [ru

  3. Wide Bandgap Extrinsic Photoconductive Switches

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, James S. [State Univ. of New York (SUNY), Plattsburgh, NY (United States); Univ. of California, Davis, CA (United States)

    2012-01-20

    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.

  4. Switching of chirality by light

    NARCIS (Netherlands)

    Feringa, B.L.; Schoevaars, A.M; Jager, W.F.; de Lange, B.; Huck, N.P.M.

    1996-01-01

    Optically active photoresponsive molecules are described by which control of chirality is achieved by light. These chiroptical molecular switches are based on inherently dissymmetric overcrowded alkenes and the synthesis, resolution and dynamic stereochemical properties are discussed. Introduction

  5. Aurora oil switch upgrade program

    International Nuclear Information System (INIS)

    Warren, T.

    1989-03-01

    This report describes the short pulse synchronization requirements, the original Aurora trigger scheme, and the PI/SNLA approach to improving the synchronization. It also describes the oil switching design study undertaken as the first phase of the program. A discussion of oil-switch closure analysis and the conceptual design motivated by this analysis are presented. This paper also describes the oil-switch trigger pulser tests required to validate the concept. This includes the design of the testing facility, a description of the test goals, and a discussion of the results. This paper finally describes oil-switch trigger pulser testing on one of the four Aurora Blumlein modules, which includes the hardware design and operation, the testing goals, hardware installation, and test results. 9 refs., 26 figs

  6. Solid state bistable power switch

    Science.gov (United States)

    Bartko, J.; Shulman, H.

    1970-01-01

    Tin and copper provide high current and switching time capabilities for high-current resettable fuses. They show the best performance for trip current and degree of reliability, and have low coefficients of thermal expansion.

  7. Intrinsic nanofilamentation in resistive switching

    KAUST Repository

    Wu, Xing; Cha, Dong Kyu; Bosman, Michel; Raghavan, Nagarajan; Migas, Dmitri B.; Borisenko, Victor E.; Zhang, Xixiang; Li, Kun; Pey, Kin-Leong

    2013-01-01

    -chip circuitry and non-volatile memory storage. Here, we provide insight into the mechanisms that govern highly reproducible controlled resistive switching via a nanofilament by using an asymmetric metal-insulator-semiconductor structure. In-situ transmission

  8. Electron collisions in gas switches

    International Nuclear Information System (INIS)

    Christophorou, L.G.

    1989-01-01

    Many technologies rely on the conduction/insulation properties of gaseous matter for their successful operation. Many others (e.g., pulsed power technologies) rely on the rapid change (switching or modulation) of the properties of gaseous matter from an insulator to a conductor and vice versa. Studies of electron collision processes in gases aided the development of pulsed power gas switches, and in this paper we shall briefly illustrate the kind of knowledge on electron collision processes which is needed to optimize the performance of such switching devices. To this end, we shall refer to three types of gas switches: spark gap closing, self-sustained diffuse discharge closing, and externally-sustained diffuse discharge opening. 24 refs., 15 figs., 2 tabs

  9. A Piezoelectric Cryogenic Heat Switch

    Science.gov (United States)

    Jahromi, Amir E.; Sullivan, Dan F.

    2014-01-01

    We have measured the thermal conductance of a mechanical heat switch actuated by a piezoelectric positioner, the PZHS (PieZo electric Heat Switch), at cryogenic temperatures. The thermal conductance of the PZHS was measured between 4 K and 10 K, and on/off conductance ratios greater than 100 were achieved when the positioner applied its maximum force of 8 N. We discuss the advantages of using this system in cryogenic applications, and estimate the ultimate performance of an optimized PZHS.

  10. High PRF high current switch

    Science.gov (United States)

    Moran, Stuart L.; Hutcherson, R. Kenneth

    1990-03-27

    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.

  11. Chromatic interocular-switch rivalry.

    Science.gov (United States)

    Christiansen, Jens H; D'Antona, Anthony D; Shevell, Steven K

    2017-05-01

    Interocular-switch rivalry (also known as stimulus rivalry) is a kind of binocular rivalry in which two rivalrous images are swapped between the eyes several times a second. The result is stable periods of one image and then the other, with stable intervals that span many eye swaps (Logothetis, Leopold, & Sheinberg, 1996). Previous work used this close kin of binocular rivalry with rivalrous forms. Experiments here test whether chromatic interocular-switch rivalry, in which the swapped stimuli differ in only chromaticity, results in slow alternation between two colors. Swapping equiluminant rivalrous chromaticities at 3.75 Hz resulted in slow perceptual color alternation, with one or the other color often continuously visible for two seconds or longer (during which there were 15+ eye swaps). A well-known theory for sustained percepts from interocular-switch rivalry with form is inhibitory competition between binocular neurons driven by monocular neurons with matched orientation tuning in each eye; such binocular neurons would produce a stable response when a given orientation is swapped between the eyes. A similar model can account for the percepts here from chromatic interocular-switch rivalry and is underpinned by the neurophysiological finding that color-preferring binocular neurons are driven by monocular neurons from each eye with well-matched chromatic selectivity (Peirce, Solomon, Forte, & Lennie, 2008). In contrast to chromatic interocular-switch rivalry, luminance interocular-switch rivalry with swapped stimuli that differ in only luminance did not result in slowly alternating percepts of different brightnesses.

  12. All-optical header recognizer for optical packet switched networks : exploiting nonlinear gain and index dynamics in semiconductor optical amplifiers for low power operation and photonic integration device

    NARCIS (Netherlands)

    Calabretta, N.; Dorren, H.J.S.

    2009-01-01

    The increase of the internet traffic leads to future optical networks requiring tens of Tb/s of capacity. Current electronic circuit switches are limited by the scalability of the electronic switching fabrics, power consumption and dissipation in the opto- electronic conversion. All-optical packet

  13. A novel micro/nano 1 × 4 mechanical optical switch

    Science.gov (United States)

    Lin, Wu-Lang; Fan, Kuang-Chao; Chiang, Li-Hung; Yang, Yao-Joe; Kuo, Wen-Cheng; Chung, Tien-Tung

    2006-07-01

    This paper presents the design, fabrication and testing of a novel 1 × 4 mechanical optical switch, whose components are fabricated by precision machining and MEMS technologies. The switch uses two relays as the two actuators whose switching direction is perpendicular to each other by an orthogonal arrangement. We adopt a direct fiber-to-fiber principle that aligns the input fiber directly to four output fibers. This configuration eliminates the use of traditional parts such as collimators, turning mirrors or prisms. In addition, due to the use of a fiber holder, the fiber position errors could be reduced to less than 0.27 µm using the two-stage geometry error reduction principle. We have successfully developed a simple and low-cost switch, which performs like most of the 1 × 4 mechanical optical switches that dominate the optics communications market. The advantages of our switch are a small size (20 × 20 × 25 mm3), low cost, high reliability, and the latching function does not need external force for maintaining the state. The experimental results showed that the insertion losses of the four channels are ch1: 0.68 dB, ch2: 1.49 dB, ch3: 0.71 dB and ch4: 0.97 dB. The switching time is 5 ms, the crosstalk <=80 dB. The reliability tests of the insertion loss after 10 000 cycles in four channels yield ch1: 1.67 dB, ch2: 1.63 dB, ch3: 0.75 dB and ch4: 0.98 dB. The size and the cost of our 1 × 4 mechanical optical switch are only about 1/5-1/10 and 1/10 of the series-connect-type and prism-type switches, respectively.

  14. Laser microstructuring for fabricating superhydrophobic polymeric surfaces

    Science.gov (United States)

    Cardoso, M. R.; Tribuzi, V.; Balogh, D. T.; Misoguti, L.; Mendonça, C. R.

    2011-02-01

    In this paper we show the fabrication of hydrophobic polymeric surfaces through laser microstructuring. By using 70-ps pulses from a Q-switched and mode-locked Nd:YAG laser at 532 nm, we were able to produce grooves with different width and separation, resulting in square-shaped pillar patterns. We investigate the dependence of the morphology on the surface static contact angle for water, showing that it is in agreement with the Cassie-Baxter model. We demonstrate the fabrication of a superhydrophobic polymeric surface, presenting a water contact angle of 157°. The surface structuring method presented here seems to be an interesting option to control the wetting properties of polymeric surfaces.

  15. CONTROL OF BOUNCING IN RF MEMS SWITCHES USING DOUBLE ELECTRODE

    KAUST Repository

    Abdul Rahim, Farhan

    2014-01-01

    MEMS based mechanical switches are seen to be the likely replacements for CMOS based switches due to the several advantages that these mechanical switches have over CMOS switches. Mechanical switches can be used in systems under extreme conditions

  16. A 2D Rods-in-Air Square-Lattice Photonic Crystal Optical Switch

    Science.gov (United States)

    2009-03-01

    4] Tao Chu, Hirohito Yamada, Satomi Ishida, Yasuhiko Arakawa, Thermooptic switch based on photonic-crystal line-defect waveguides, IEEE Photon...Ishida, Yasuhiko Arakawa, Hiroyuki Fujita, Hiroshi Toshiyoshi, Design and fabrication on MEMS optical mod- ulators integrated with Phc waveguide, in

  17. Tuning the resistive switching properties of TiO2-x films

    Science.gov (United States)

    Ghenzi, N.; Rozenberg, M. J.; Llopis, R.; Levy, P.; Hueso, L. E.; Stoliar, P.

    2015-03-01

    We study the electrical characteristics of TiO2-x-based resistive switching devices fabricated with different oxygen/argon flow ratio during the oxide thin film sputtering deposition. Upon minute changes in this fabrication parameter, three qualitatively different device characteristics were accessed in the same system, namely, standard bipolar resistive switching, electroforming-free devices, and devices with multi-step breakdown. We propose that small variations in the oxygen/ argon flow ratio result in relevant changes of the oxygen vacancy concentration, which is the key parameter determining the resistive switching behavior. The coexistence of percolative or non-percolative conductive filaments is also discussed. Finally, the hypothesis is verified by means of the temperature dependence of the devices in low resistance state.

  18. Switched capacitor DC-DC converter with switch conductance modulation and Pesudo-fixed frequency control

    DEFF Research Database (Denmark)

    Larsen, Dennis Øland; Vinter, Martin; Jørgensen, Ivan Harald Holger

    A switched capacitor dc-dc converter with frequency-planned control is presented. By splitting the output stage switches in eight segments the output voltage can be regulated with a combination of switching frequency and switch conductance. This allows for switching at predetermined frequencies, 31...

  19. A Switch Is Not a Switch: Syntactically-Driven Bilingual Language Control

    Science.gov (United States)

    Gollan, Tamar H.; Goldrick, Matthew

    2018-01-01

    The current study investigated the possibility that language switches could be relatively automatically triggered by context. "Single-word switches," in which bilinguals switched languages on a single word in midsentence and then immediately switched back, were contrasted with more complete "whole-language switches," in which…

  20. Principles of broadband switching and networking

    CERN Document Server

    Liew, Soung C

    2010-01-01

    An authoritative introduction to the roles of switching and transmission in broadband integrated services networks Principles of Broadband Switching and Networking explains the design and analysis of switch architectures suitable for broadband integrated services networks, emphasizing packet-switched interconnection networks with distributed routing algorithms. The text examines the mathematical properties of these networks, rather than specific implementation technologies. Although the pedagogical explanations in this book are in the context of switches, many of the fundamenta

  1. Resistive switching in polycrystalline YMnO3 thin films

    Directory of Open Access Journals (Sweden)

    A. Bogusz

    2014-10-01

    Full Text Available We report a unipolar, nonvolatile resistive switching in polycrystalline YMnO3 thin films grown by pulsed laser deposition and sandwiched between Au top and Ti/Pt bottom electrodes. The ratio of the resistance in the OFF and ON state is larger than 103. The observed phenomena can be attributed to the formation and rupture of conductive filaments within the multiferroic YMnO3 film. The generation of conductive paths under applied electric field is discussed in terms of the presence of grain boundaries and charged domain walls inherently formed in hexagonal YMnO3. Our findings suggest that engineering of the ferroelectric domains might be a promising route for designing and fabrication of novel resistive switching devices.

  2. A smart microelectromechanical sensor and switch triggered by gas

    KAUST Repository

    Bouchaala, Adam M.

    2016-07-05

    There is an increasing interest to realize smarter sensors and actuators that can deliver a multitude of sophisticated functionalities while being compact in size and of low cost. We report here combining both sensing and actuation on the same device based on a single microstructure. Specifically, we demonstrate a smart resonant gas (mass) sensor, which in addition to being capable of quantifying the amount of absorbed gas, can be autonomously triggered as an electrical switch upon exceeding a preset threshold of absorbed gas. Toward this, an electrostatically actuated polymer microbeam is fabricated and is then functionalized with a metal-organic framework, namely, HKUST-1. The microbeam is demonstrated to absorb vapors up to a certain threshold, after which is shown to collapse through the dynamic pull-in instability. Upon pull-in, the microstructure can be made to act as an electrical switch to achieve desirable actions, such as alarming.

  3. Resistive switching in microscale anodic titanium dioxide-based memristors

    Science.gov (United States)

    Aglieri, V.; Zaffora, A.; Lullo, G.; Santamaria, M.; Di Franco, F.; Lo Cicero, U.; Mosca, M.; Macaluso, R.

    2018-01-01

    The potentiality of anodic TiO2 as an oxide material for the realization of resistive switching memory cells has been explored in this paper. Cu/anodic-TiO2/Ti memristors of different sizes, ranging from 1 × 1 μm2 to 10 × 10 μm2 have been fabricated and characterized. The oxide films were grown by anodizing Ti films, using three different process conditions. Measured IV curves have shown similar asymmetric bipolar hysteresis behaviors in all the tested devices, with a gradual switching from the high resistance state to the low resistance state and vice versa, and a ROFF/RON ratio of 80 for the thickest oxide film devices.

  4. Morphing hydrogel patterns by thermo-reversible fluorescence switching.

    Science.gov (United States)

    Bat, Erhan; Lin, En-Wei; Saxer, Sina; Maynard, Heather D

    2014-07-01

    Stimuli responsive surfaces that show reversible fluorescence switching behavior in response to temperature changes were fabricated. Oligo(ethylene glycol) methacrylate thermoresponsive polymers with amine end-groups were prepared by atom transfer radical polymerization (ATRP). The polymers were patterned on silicon surfaces by electron beam (e-beam) lithography, followed by conjugation of self-quenching fluorophores. Fluorophore conjugated hydrogel thin films were bright when the gels were swollen; upon temperature-induced collapse of the gels, self-quenching of the fluorophores led to significant attenuation of fluorescence. Importantly, the fluorescence was regained when the temperature was cooled. The fluorescence switching behavior of the hydrogels for up to ten cycles was investigated and the swelling-collapse was verified by atomic force microscopy. Morphing surfaces that change shape several times upon increase in temperature were obtained by patterning multiple stimuli responsive polymers. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. A smart microelectromechanical sensor and switch triggered by gas

    Science.gov (United States)

    Bouchaala, Adam; Jaber, Nizar; Shekhah, Osama; Chernikova, Valeriya; Eddaoudi, Mohamed; Younis, Mohammad I.

    2016-07-01

    There is an increasing interest to realize smarter sensors and actuators that can deliver a multitude of sophisticated functionalities while being compact in size and of low cost. We report here combining both sensing and actuation on the same device based on a single microstructure. Specifically, we demonstrate a smart resonant gas (mass) sensor, which in addition to being capable of quantifying the amount of absorbed gas, can be autonomously triggered as an electrical switch upon exceeding a preset threshold of absorbed gas. Toward this, an electrostatically actuated polymer microbeam is fabricated and is then functionalized with a metal-organic framework, namely, HKUST-1. The microbeam is demonstrated to absorb vapors up to a certain threshold, after which is shown to collapse through the dynamic pull-in instability. Upon pull-in, the microstructure can be made to act as an electrical switch to achieve desirable actions, such as alarming.

  6. Investigation of switching region in superlattice phase change memories

    Science.gov (United States)

    Ohyanagi, T.; Takaura, N.

    2016-10-01

    We investigated superlattice phase change memories (PCMs) to clarify which regions were responsible for switching. We observed atomic structures in a superlattice PCM film with a stack of GeTe / Sb2Te3 layers using atomically resolved EDX maps, and we found an intermixed region with three atom species of the Ge, Sb and Te around the top GeTe layer under the top electrode. We also found that a device with a GeTe layer on an Sb2Te3 layer without superlattice structure had the same switching characteristics as a device with a superlattice PCM, that had the same top GeTe layer. We developed and fabricated a modified superlattice PCM that attained ultra low Reset / Set currents under 60 μ A .

  7. Fabric based supercapacitor

    International Nuclear Information System (INIS)

    Yong, S; Tudor, M J; Beeby, S P; Owen, J R

    2013-01-01

    Flexible supercapacitors with electrodes coated on inexpensive fabrics by the dipping technique. This paper present details of the design, fabrication and characterisation of fabric supercapacitor. The sandwich structured supercapacitors can achieve specific capacitances of 11.1F/g, area capacitance 105 mF.cm −2 and maintain 95% of the initial capacitance after cycling the device for more than 15000 times

  8. Switching dynamics of TaOx-based threshold switching devices

    Science.gov (United States)

    Goodwill, Jonathan M.; Gala, Darshil K.; Bain, James A.; Skowronski, Marek

    2018-03-01

    Bi-stable volatile switching devices are being used as access devices in solid-state memory arrays and as the active part of compact oscillators. Such structures exhibit two stable states of resistance and switch between them at a critical value of voltage or current. A typical resistance transient under a constant amplitude voltage pulse starts with a slow decrease followed by a rapid drop and leveling off at a low steady state value. This behavior prompted the interpretation of initial delay and fast transition as due to two different processes. Here, we show that the entire transient including incubation time, transition time, and the final resistance values in TaOx-based switching can be explained by one process, namely, Joule heating with the rapid transition due to the thermal runaway. The time, which is required for the device in the conducting state to relax back to the stable high resistance one, is also consistent with the proposed mechanism.

  9. Fabrication and testing of a superconducting coil: Phase 3 of the Maglev development program

    Energy Technology Data Exchange (ETDEWEB)

    Fife, A A; Lee, S; Tillotson, M [CTF Systems Inc., Port Coquitlam, BC (Canada)

    1989-03-01

    This report documents developmental research on superconducting magnet technology suitable for the levitation and propulsion units of the Canadian Maglev vehicle. The contract work involved the design, fabrication and testing of a racetrack coil fabricated using epoxy-impregnated windings of copper stabilized NbTi wire. The following results were achieved: successful fabrication and testing of a superconducting racetrack magnet with strength {gt} 400,000 A-turns integrated in a support frame; selection and characterization of cryogenic strain gauges; characterization of strain in solenoidal and racetrack superconducting magnets; design, fabrication and testing of high current persistent switches; and operation of superconducting magnets in persistent mode. The racetrack coil reached the design current after the third quench and short sample critical current after the eighth quench. This behavior is essentially identical to that observed with a superconducting solenoid fabricated during a previous phase. The strain measured perpendicular to the straight sides of the racetrack coil was proportional to the square of the energizing current. Persistent switches were fabricated, one type with low resistance (10{sup -2} ohm) and the other with high resistance (1.2 ohm) in their normal states. The low resistance switch could be operated in 1-Tesla fields with stabel characteristics up to about 800A drive current and the high resistance switch to 475A.

  10. IGBT: a solid state switch

    International Nuclear Information System (INIS)

    Chatroux, D.; Maury, J.; Hennevin, B.

    1993-01-01

    A Copper Vapour Laser Power Supply has been designed using a solid state switch consisting in eighteen Isolated Gate Bipolar Transistors (IGBT), -1200 volts, 400 Amps, each-in parallel. This paper presents the Isolated Gate Bipolar Transistor (IGBTs) replaced in the Power Electronic components evolution, and describes the IGBT conduction mechanism, presents the parallel association of IGBTs, and studies the application of these components to a Copper Vapour Laser Power Supply. The storage capacitor voltage is 820 volts, the peak current of the solid state switch is 17.000 Amps. The switch is connected on the primary of a step-up transformer, followed by a magnetic modulator. The reset of the magnetic modulator is provided by part of the laser reflected energy with a patented circuit. The charging circuit is a resonant circuit with a charge controlled by an IGBT switch. When the switch is open, the inductance energy is free-wheeled by an additional winding and does not extend the charging phase of the storage capacitor. The design allows the storage capacitor voltage to be very well regulated. This circuit is also patented. The electric pulse in the laser has 30.000 Volt peak voltage, 2000 Amp peak current, and is 200 nanoseconds long, for a 200 Watt optical power Copper Vapour Laser

  11. A miniaturized reconfigurable broadband attenuator based on RF MEMS switches

    International Nuclear Information System (INIS)

    Guo, Xin; Gong, Zhuhao; Zhong, Qi; Liang, Xiaotong; Liu, Zewen

    2016-01-01

    Reconfigurable attenuators are widely used in microwave measurement instruments. Development of miniaturized attenuation devices with high precision and broadband performance is required for state-of-the-art applications. In this paper, a compact 3-bit microwave attenuator based on radio frequency micro-electro-mechanical system (RF MEMS) switches and polysilicon attenuation modules is presented. The device comprises 12 ohmic contact MEMS switches, π -type polysilicon resistive attenuation modules and microwave compensate structures. Special attention was paid to the design of the resistive network, compensate structures and system simulation. The device was fabricated using micromachining processes compatible with traditional integrated circuit fabrication processes. The reconfigurable attenuator integrated with RF MEMS switches and resistive attenuation modules was successfully fabricated with dimensions of 2.45  ×  4.34  ×  0.5 mm 3 , which is 1/1000th of the size of a conventional step attenuator. The measured RF performance revealed that the attenuator provides 10–70 dB attenuation at 10 dB intervals from 0.1–20 GHz with an accuracy better than  ±1.88 dB at 60 dB and an error of less than 2.22 dB at 10 dB. The return loss of each state of the 3-bit attenuator was better than 11.95 dB (VSWR  <  1.71) over the entire operating band. (paper)

  12. Atomic Scale Modulation of Self-Rectifying Resistive Switching by Interfacial Defects

    KAUST Repository

    Wu, Xing; Yu, Kaihao; Cha, Dong Kyu; Bosman, Michel; Raghavan, Nagarajan; Zhang, Xixiang; Li, Kun; Liu, Qi; Sun, Litao; Pey, Kinleong

    2018-01-01

    Higher memory density and faster computational performance of resistive switching cells require reliable array‐accessible architecture. However, selecting a designated cell within a crossbar array without interference from sneak path currents through neighboring cells is a general problem. Here, a highly doped n++ Si as the bottom electrode with Ni‐electrode/HfOx/SiO2 asymmetric self‐rectifying resistive switching device is fabricated. The interfacial defects in the HfOx/SiO2 junction and n++ Si substrate result in the reproducible rectifying behavior. In situ transmission electron microscopy is used to quantitatively study the properties of the morphology, chemistry, and dynamic nucleation–dissolution evolution of the chains of defects at the atomic scale. The spatial and temporal correlation between the concentration of oxygen vacancies and Ni‐rich conductive filament modifies the resistive switching effect. This study has important implications at the array‐level performance of high density resistive switching memories.

  13. Atomic Scale Modulation of Self-Rectifying Resistive Switching by Interfacial Defects

    KAUST Repository

    Wu, Xing

    2018-04-14

    Higher memory density and faster computational performance of resistive switching cells require reliable array‐accessible architecture. However, selecting a designated cell within a crossbar array without interference from sneak path currents through neighboring cells is a general problem. Here, a highly doped n++ Si as the bottom electrode with Ni‐electrode/HfOx/SiO2 asymmetric self‐rectifying resistive switching device is fabricated. The interfacial defects in the HfOx/SiO2 junction and n++ Si substrate result in the reproducible rectifying behavior. In situ transmission electron microscopy is used to quantitatively study the properties of the morphology, chemistry, and dynamic nucleation–dissolution evolution of the chains of defects at the atomic scale. The spatial and temporal correlation between the concentration of oxygen vacancies and Ni‐rich conductive filament modifies the resistive switching effect. This study has important implications at the array‐level performance of high density resistive switching memories.

  14. Organic-based molecular switches for molecular electronics.

    Science.gov (United States)

    Fuentes, Noelia; Martín-Lasanta, Ana; Alvarez de Cienfuegos, Luis; Ribagorda, Maria; Parra, Andres; Cuerva, Juan M

    2011-10-05

    In a general sense, molecular electronics (ME) is the branch of nanotechnology which studies the application of molecular building blocks for the fabrication of electronic components. Among the different types of molecules, organic compounds have been revealed as promising candidates for ME, due to the easy access, great structural diversity and suitable electronic and mechanical properties. Thanks to these useful capabilities, organic molecules have been used to emulate electronic devices at the nanoscopic scale. In this feature article, we present the diverse strategies used to develop organic switches towards ME with special attention to non-volatile systems.

  15. Fabrics in Function

    DEFF Research Database (Denmark)

    Bang, Anne Louise

    2007-01-01

    sensing of fabrics in function. It is proposed that tactile and visual sensing of fabrics is a way to investigate and express emotional utility values. The further purpose is to use experiments with repertory grid models as part of the mapping of the entire research project and also as a basis...

  16. Fabricating architectural volume

    DEFF Research Database (Denmark)

    Feringa, Jelle; Søndergaard, Asbjørn

    2015-01-01

    The 2011 edition of Fabricate inspired a number of collaborations, this article seeks to highlight three of these. There is a common thread amongst the projects presented: sharing the ambition to close the rift between design and fabrication while incorporating structural design aspects early on...

  17. Smart Fabrics Technology Development

    Science.gov (United States)

    Simon, Cory; Potter, Elliott; Potter, Elliott; McCabe, Mary; Baggerman, Clint

    2010-01-01

    Advances in Smart Fabrics technology are enabling an exciting array of new applications for NASA exploration missions, the biomedical community, and consumer electronics. This report summarizes the findings of a brief investigation into the state of the art and potential applications of smart fabrics to address challenges in human spaceflight.

  18. CMOS integrated switching power converters

    CERN Document Server

    Villar-Pique, Gerard

    2011-01-01

    This book describes the structured design and optimization of efficient, energy processing integrated circuits. The approach is multidisciplinary, covering the monolithic integration of IC design techniques, power electronics and control theory. In particular, this book enables readers to conceive, synthesize, design and implement integrated circuits with high-density high-efficiency on-chip switching power regulators. Topics covered encompass the structured design of the on-chip power supply, efficiency optimization, IC-compatible power inductors and capacitors, power MOSFET switches and effi

  19. All-fiber polarization switch

    Science.gov (United States)

    Knape, Harald; Margulis, Walter

    2007-03-01

    We report an all-fiber polarization switch made out of silica-based microstructured fiber suitable for Q-switching all-fiber lasers. Nanosecond high-voltage pulses are used to heat and expand an internal electrode to cause λ/2-polarization rotation in less than 10 ns for 1.5 μm light. The 10 cm long component has an experimentally measured optical insertion loss of 0.2 dB and a 0-10 kHz repetition frequency capacity and has been durability tested for more than 109 pulses.

  20. Laser-fabricated castor oil-capped silver nanoparticles.

    Science.gov (United States)

    Zamiri, Reza; Zakaria, Azmi; Abbastabar, Hossein; Darroudi, Majid; Husin, Mohd Shahril; Mahdi, Mohd Adzir

    2011-01-01

    Silver nanoparticles were fabricated by ablation of a pure silver plate immersed in castor oil. A Nd:YAG-pulsed Q-switch laser with 1064-nm wavelength and 10-Hz frequency was used to ablate the plate for 10 minutes. The sample was characterized by ultraviolet-visible, atomic absorption, Fourier transform-infrared spectroscopies, and transmission electron microscopy. The results of the fabricated sample showed that the nanoparticles in castor oil were about 5-nm in diameter, well dispersed, and showed stability for a long period of time.

  1. Optically controlled multiple switching operations of DNA biopolymer devices

    International Nuclear Information System (INIS)

    Hung, Chao-You; Tu, Waan-Ting; Lin, Yi-Tzu; Fruk, Ljiljana; Hung, Yu-Chueh

    2015-01-01

    We present optically tunable operations of deoxyribonucleic acid (DNA) biopolymer devices, where a single high-resistance state, write-once read-many-times memory state, write-read-erase memory state, and single low-resistance state can be achieved by controlling UV irradiation time. The device is a simple sandwich structure with a spin-coated DNA biopolymer layer sandwiched by two electrodes. Upon irradiation, the electrical properties of the device are adjusted owing to a phototriggered synthesis of silver nanoparticles in DNA biopolymer, giving rise to multiple switching scenarios. This technique, distinct from the strategy of doping of pre-formed nanoparticles, enables a post-film fabrication process for achieving optically controlled memory device operations, which provides a more versatile platform to fabricate organic memory and optoelectronic devices

  2. Optically controlled multiple switching operations of DNA biopolymer devices

    Energy Technology Data Exchange (ETDEWEB)

    Hung, Chao-You; Tu, Waan-Ting; Lin, Yi-Tzu [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Fruk, Ljiljana [Department of Chemical Engineering and Biotechnology, University of Cambridge, Pembroke Street, Cambridge CB2 3RA (United Kingdom); Hung, Yu-Chueh, E-mail: ychung@ee.nthu.edu.tw [Institute of Photonics Technologies, National Tsing Hua University, Hsinchu 30013, Taiwan (China); Department of Electrical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan (China)

    2015-12-21

    We present optically tunable operations of deoxyribonucleic acid (DNA) biopolymer devices, where a single high-resistance state, write-once read-many-times memory state, write-read-erase memory state, and single low-resistance state can be achieved by controlling UV irradiation time. The device is a simple sandwich structure with a spin-coated DNA biopolymer layer sandwiched by two electrodes. Upon irradiation, the electrical properties of the device are adjusted owing to a phototriggered synthesis of silver nanoparticles in DNA biopolymer, giving rise to multiple switching scenarios. This technique, distinct from the strategy of doping of pre-formed nanoparticles, enables a post-film fabrication process for achieving optically controlled memory device operations, which provides a more versatile platform to fabricate organic memory and optoelectronic devices.

  3. Optics fabrication technical challenges

    International Nuclear Information System (INIS)

    Chabassier, G.; Ferriou, N.; Lavastre, E.; Maunier, C.; Neauport, J.; Taroux, D.; Balla, D.; Fornerod, J.C.

    2004-01-01

    Before the production of all the LMJ (MEGAJOULE laser) optics, the CEA had to proceed with the fabrication of about 300 large optics for the LIL (laser integration line) laser. Thanks to a fruitful collaboration with high-tech optics companies in Europe, this challenge has been successfully hit. In order to achieve the very tight requirements for cleanliness, laser damage threshold and all the other high demanding fabrication specifications, it has been necessary to develop and to set completely new fabrication process going and to build special outsize fabrication equipment. Through a couple of examples, this paper gives an overview of the work which has been done and shows some of the results which have been obtained: continuous laser glass melting, fabrication of the laser slabs, rapid-growth KDP (potassium dihydrogen phosphate) technology, large diffractive transmission gratings engraving and characterization. (authors)

  4. Non-switching to switching transferring mechanism investigation for Ag/SiO x /p-Si structure with SiO x deposited by HWCVD

    Science.gov (United States)

    Liu, Yanhong; Wang, Ruoying; Li, Zhongyue; Wang, Song; Huang, Yang; Peng, Wei

    2018-04-01

    We proposed and fabricated an Ag/SiO x /p-Si sandwich structure, in which amorphous SiO x films were deposited through hot wire chemical vapor deposition (HWCVD) using tetraethylorthosilicate (TEOS) as Si and O precursor. Experimental results indicate that the I–V properties of this structure transfer from non-switching to switching operation as the SiO x deposition temperature increased. The device with SiO x deposited at high deposition temperature exhibits typical bipolar switching properties, which can be potentially used in resistive switching random accessible memory (RRAM). The transferring mechanism from non-switching to switching can be ascribed to the change of structural and electronic properties of SiO x active layer deposited at different temperatures, as evidenced by analyzing FTIR spectrum and fitting its I–V characteristics curves. This work demonstrates a safe and practicable low-temperature device-grade SiO x film deposition technology by conducting HWCVD from TEOS.

  5. A level switch with a sound tube

    OpenAIRE

    赤池, 誠規

    2017-01-01

    Level switches are sensor with an electrical contact output at a specific liquid, powder or bulk level. Most of traditional level switches are not suitable for harsh environments. The level switch in this study connects a loudspeaker on top end of the sound tube. When liquid, powder or bulk closes bottom end of the sound tube, the level switch turns on. The level switch is suitable for harsh environments and easy to install. The aim of this study is to propose a level switch with a sound tube...

  6. Dual-functional Memory and Threshold Resistive Switching Based on the Push-Pull Mechanism of Oxygen Ions

    KAUST Repository

    Huang, Yi-Jen

    2016-04-07

    The combination of nonvolatile memory switching and volatile threshold switching functions of transition metal oxides in crossbar memory arrays is of great potential for replacing charge-based flash memory in very-large-scale integration. Here, we show that the resistive switching material structure, (amorphous TiOx)/(Ag nanoparticles)/(polycrystalline TiOx), fabricated on the textured-FTO substrate with ITO as the top electrode exhibits both the memory switching and threshold switching functions. When the device is used for resistive switching, it is forming-free for resistive memory applications with low operation voltage (<±1 V) and self-compliance to current up to 50 μA. When it is used for threshold switching, the low threshold current is beneficial for improving the device selectivity. The variation of oxygen distribution measured by energy dispersive X-ray spectroscopy and scanning transmission electron microscopy indicates the formation or rupture of conducting filaments in the device at different resistance states. It is therefore suggested that the push and pull actions of oxygen ions in the amorphous TiOx and polycrystalline TiOx films during the voltage sweep account for the memory switching and threshold switching properties in the device.

  7. Industry switching in developing countries

    DEFF Research Database (Denmark)

    Newman, Carol; Rand, John; Tarp, Finn

    2013-01-01

    Firm turnover (i.e., firm entry and exit) is a well-recognized source of sector-level productivity growth. In contrast, the role and importance of firms that switch activities from one sector to another is not well understood. Firm switchers are likely to be unique, differing from both newly esta...

  8. Nanoscale organic ferroelectric resistive switches

    NARCIS (Netherlands)

    Khikhlovskyi, V.; Wang, R.; Breemen, A.J.J.M. van; Gelinck, G.H.; Janssen, R.A.J.; Kemerink, M.

    2014-01-01

    Organic ferroelectric resistive switches function by grace of nanoscale phase separation in a blend of a semiconducting and a ferroelectric polymer that is sandwiched between metallic electrodes. In this work, various scanning probe techniques are combined with numerical modeling to unravel their

  9. Design of convergent switched systems

    NARCIS (Netherlands)

    Berg, van den R.A.; Pogromsky, A.Y.; Leonov, G.A.; Rooda, J.E.; Pettersen, K.Y.; Gravdahl, J.T.; Nijmeijer, H.

    2006-01-01

    In this paper we deal with the problem of rendering hybrid/nonlinear systems into convergent closed-loop systems by means of a feedback law or switching rules. We illustrate our approach to this problem by means of two examples: the anti-windup design for a marginally stable system with input

  10. Incorrect predictions reduce switch costs.

    Science.gov (United States)

    Kleinsorge, Thomas; Scheil, Juliane

    2015-07-01

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

  11. Multiuser switched diversity scheduling schemes

    KAUST Repository

    Shaqfeh, Mohammad; Alnuweiri, Hussein M.; Alouini, Mohamed-Slim

    2012-01-01

    Multiuser switched-diversity scheduling schemes were recently proposed in order to overcome the heavy feedback requirements of conventional opportunistic scheduling schemes by applying a threshold-based, distributed, and ordered scheduling mechanism. The main idea behind these schemes is that slight reduction in the prospected multiuser diversity gains is an acceptable trade-off for great savings in terms of required channel-state-information feedback messages. In this work, we characterize the achievable rate region of multiuser switched diversity systems and compare it with the rate region of full feedback multiuser diversity systems. We propose also a novel proportional fair multiuser switched-based scheduling scheme and we demonstrate that it can be optimized using a practical and distributed method to obtain the feedback thresholds. We finally demonstrate by numerical examples that switched-diversity scheduling schemes operate within 0.3 bits/sec/Hz from the ultimate network capacity of full feedback systems in Rayleigh fading conditions. © 2012 IEEE.

  12. Stability of Randomly Switched Diffusions

    DEFF Research Database (Denmark)

    Schiøler, Henrik; Leth, John-Josef; Gholami, Mehdi

    2012-01-01

    This paper provides a sufficient criterion for ε-moment stability (boundedness) and ergodicity for a class of systems comprising a finite set of diffusions among which switching is governed by a continuous time Markov chain. Stability/instability properties for each separate subsystem are assumed...

  13. Industry Switching in Developing Countries

    DEFF Research Database (Denmark)

    Newman, Carol; Rand, John; Tarp, Finn

    Firm turnover (i.e. firm entry and exit) is a well-recognized source of sectorlevel productivity growth across developing and developed countries. In contrast, the role and importance of firms switching activities from one sector to another is little understood. Firm switchers are likely...

  14. Charge transport through molecular switches

    International Nuclear Information System (INIS)

    Jan van der Molen, Sense; Liljeroth, Peter

    2010-01-01

    We review the fascinating research on charge transport through switchable molecules. In the past decade, detailed investigations have been performed on a great variety of molecular switches, including mechanically interlocked switches (rotaxanes and catenanes), redox-active molecules and photochromic switches (e.g. azobenzenes and diarylethenes). To probe these molecules, both individually and in self-assembled monolayers (SAMs), a broad set of methods have been developed. These range from low temperature scanning tunneling microscopy (STM) via two-terminal break junctions to larger scale SAM-based devices. It is generally found that the electronic coupling between molecules and electrodes has a profound influence on the properties of such molecular junctions. For example, an intrinsically switchable molecule may lose its functionality after it is contacted. Vice versa, switchable two-terminal devices may be created using passive molecules ('extrinsic switching'). Developing a detailed understanding of the relation between coupling and switchability will be of key importance for both future research and technology. (topical review)

  15. Charge transport through molecular switches

    Energy Technology Data Exchange (ETDEWEB)

    Jan van der Molen, Sense [Kamerlingh Onnes Laboratorium, Leiden University, Niels Bohrweg 2, 2333 CA Leiden (Netherlands); Liljeroth, Peter, E-mail: molen@physics.leidenuniv.n [Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science, University of Utrecht, PO Box 80000, 3508 TA Utrecht (Netherlands)

    2010-04-07

    We review the fascinating research on charge transport through switchable molecules. In the past decade, detailed investigations have been performed on a great variety of molecular switches, including mechanically interlocked switches (rotaxanes and catenanes), redox-active molecules and photochromic switches (e.g. azobenzenes and diarylethenes). To probe these molecules, both individually and in self-assembled monolayers (SAMs), a broad set of methods have been developed. These range from low temperature scanning tunneling microscopy (STM) via two-terminal break junctions to larger scale SAM-based devices. It is generally found that the electronic coupling between molecules and electrodes has a profound influence on the properties of such molecular junctions. For example, an intrinsically switchable molecule may lose its functionality after it is contacted. Vice versa, switchable two-terminal devices may be created using passive molecules ('extrinsic switching'). Developing a detailed understanding of the relation between coupling and switchability will be of key importance for both future research and technology. (topical review)

  16. Wide Bandgap Extrinsic Photoconductive Switches

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, James S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-07-03

    Semi-insulating Gallium Nitride, 4H and 6H Silicon Carbide are attractive materials for compact, high voltage, extrinsic, photoconductive switches due to their wide bandgap, high dark resistance, high critical electric field strength and high electron saturation velocity. These wide bandgap semiconductors are made semi-insulating by the addition of vanadium (4H and 6HSiC) and iron (2H-GaN) impurities that form deep acceptors. These deep acceptors trap electrons donated from shallow donor impurities. The electrons can be optically excited from these deep acceptor levels into the conduction band to transition the wide bandgap semiconductor materials from a semi-insulating to a conducting state. Extrinsic photoconductive switches with opposing electrodes have been constructed using vanadium compensated 6H-SiC and iron compensated 2H-GaN. These extrinsic photoconductive switches were tested at high voltage and high power to determine if they could be successfully used as the closing switch in compact medical accelerators.

  17. The Atlas load protection switch

    CERN Document Server

    Davis, H A; Dorr, G; Martínez, M; Gribble, R F; Nielsen, K E; Pierce, D; Parsons, W M

    1999-01-01

    Atlas is a high-energy pulsed-power facility under development to study materials properties and hydrodynamics experiments under extreme conditions. Atlas will implode heavy liner loads (m~45 gm) with a peak current of 27-32 MA delivered in 4 mu s, and is energized by 96, 240 kV Marx generators storing a total of 23 MJ. A key design requirement for Atlas is obtaining useful data for 95601130f all loads installed on the machine. Materials response calculations show current from a prefire can damage the load requiring expensive and time consuming replacement. Therefore, we have incorporated a set of fast-acting mechanical switches in the Atlas design to reduce the probability of a prefire damaging the load. These switches, referred to as the load protection switches, short the load through a very low inductance path during system charge. Once the capacitors have reached full charge, the switches open on a time scale short compared to the bank charge time, allowing current to flow to the load when the trigger pu...

  18. Intrinsic nanofilamentation in resistive switching

    KAUST Repository

    Wu, Xing

    2013-03-15

    Resistive switching materials are promising candidates for nonvolatile data storage and reconfiguration of electronic applications. Intensive studies have been carried out on sandwiched metal-insulator-metal structures to achieve high density on-chip circuitry and non-volatile memory storage. Here, we provide insight into the mechanisms that govern highly reproducible controlled resistive switching via a nanofilament by using an asymmetric metal-insulator-semiconductor structure. In-situ transmission electron microscopy is used to study in real-time the physical structure and analyze the chemical composition of the nanofilament dynamically during resistive switching. Electrical stressing using an external voltage was applied by a tungsten tip to the nanosized devices having hafnium oxide (HfO2) as the insulator layer. The formation and rupture of the nanofilaments result in up to three orders of magnitude change in the current flowing through the dielectric during the switching event. Oxygen vacancies and metal atoms from the anode constitute the chemistry of the nanofilament.

  19. Multiuser switched diversity scheduling schemes

    KAUST Repository

    Shaqfeh, Mohammad

    2012-09-01

    Multiuser switched-diversity scheduling schemes were recently proposed in order to overcome the heavy feedback requirements of conventional opportunistic scheduling schemes by applying a threshold-based, distributed, and ordered scheduling mechanism. The main idea behind these schemes is that slight reduction in the prospected multiuser diversity gains is an acceptable trade-off for great savings in terms of required channel-state-information feedback messages. In this work, we characterize the achievable rate region of multiuser switched diversity systems and compare it with the rate region of full feedback multiuser diversity systems. We propose also a novel proportional fair multiuser switched-based scheduling scheme and we demonstrate that it can be optimized using a practical and distributed method to obtain the feedback thresholds. We finally demonstrate by numerical examples that switched-diversity scheduling schemes operate within 0.3 bits/sec/Hz from the ultimate network capacity of full feedback systems in Rayleigh fading conditions. © 2012 IEEE.

  20. High voltage MOSFET switching circuit

    Science.gov (United States)

    McEwan, Thomas E.

    1994-01-01

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

  1. VO{sub 2}-like thermo-optical switching effect in one-dimensional nonlinear defective photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Juan, E-mail: juanzhang@staff.shu.edu.cn, E-mail: ywang@siom.ac.cn; Zhang, Rongjun [Key Laboratory of Specialty Fiber Optics and Optical Access Networks, School of Communication and Information Engineering, Shanghai University, Shanghai 200072 (China); Wang, Yang, E-mail: juanzhang@staff.shu.edu.cn, E-mail: ywang@siom.ac.cn [Key Laboratory of High Power Laser Materials, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China)

    2015-06-07

    A new approach to achieve VO{sub 2}-like thermo-optical switching in a one-dimensional photonic crystal by the combination of thermo-optical and optical Kerr effects was proposed and numerically demonstrated in this study. The switching temperature and the hysteresis width can be tuned in a wide temperature range. Steep transition, high optical contrast, and low pumping power can be achieved at the same time. This kind of one-dimensional photonic crystal-based bistable switch will be low-cost, easy-to-fabricate, and versatile in practical applications compared with traditional VO{sub 2}-type one.

  2. New polymorphous computing fabric

    International Nuclear Information System (INIS)

    Wolinski, Christophe; Gokhale, Maya; McCabe, Kevin P.

    2002-01-01

    This paper introduces a new polymorphous computing Fabric well suited to DSP and Image Processing and describes its implementation on a Configurable System on a Chip (CSOC). The architecture is highly parameterized and enables customization of the synthesized Fabric to achieve high performance for a specific class of application. For this reason it can be considered to be a generic model for hardware accelerator synthesis from a high level specification. Another important innovation is the Fabric uses a global memory concept, which gives the host processor random access to all the variables and instructions on the Fabric. The Fabric supports different computing models including MIMD, SPMD and systolic flow and permits dynamic reconfiguration. We present a specific implementation of a bank of FIR filters on a Fabric composed of 52 cells on the Altera Excalibur ARM running at 33 MHz. The theoretical performance of this Fabric is 1.8 GMACh. For the FIR application we obtain 1.6 GMAC/s real performance. Some automatic tools have been developed like the tool to provide a host access utility and assembler.

  3. Resistive switching in TiO{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Lin

    2011-10-26

    The continuing improved performance of the digital electronic devices requires new memory technologies which should be inexpensively fabricated for higher integration capacity, faster operation, and low power consumption. Resistive random access memory has great potential to become the front runner as the non volatile memory technology. The resistance states stored in such cell can remain for long time and can be read out none-destructively by a very small electrical pulse. In this work the typically two terminal memory cells containing a thin TiO{sub 2} layer are studied. Polycrystalline TiO{sub 2} thin films are deposited with atomic layer deposition and magnetron reactive sputtering processes, which are both physically and electrically characterized. The resistive switching cells are constructed in a metal/TiO{sub 2}/metal structure. Electroforming process initiate the cell from the beginning good insulator to a real memory cell to program the resistive states. Multilevel resistive bipolar switching controlled by current compliance is the common characteristic observed in these cells, which is potentially to be used as so called multi-bit memory cells to improve the memory capacity. With different top electrodes of Pt, Cu, Ag the resistive switching behaviors are studied. The switching behaviors are different depending on the top metal such as the minimum current compliance, the endurance of the programmed resistance states and the morphology change during the switching. The temperature dependence of different resistance states are investigated. A reduction of the activation energy and their possible conduction mechanisms is discussed on the base of the basic current conduction models. It is found that the resistance state transfers from semiconductor to metallic property with the reducing resistances. The calculated temperature coefficients of their metallic states on the Cu/TiO{sub 2}/Pt and Ag/TiO{sub 2}/Pt are very close to the reported literature data

  4. Switch-connected HyperX network

    Science.gov (United States)

    Chen, Dong; Heidelberger, Philip

    2018-02-13

    A network system includes a plurality of sub-network planes and global switches. The sub-network planes have a same network topology as each other. Each of the sub-network planes includes edge switches. Each of the edge switches has N ports. Each of the global switches is configured to connect a group of edge switches at a same location in the sub-network planes. In each of the sub-network planes, some of the N ports of each of the edge switches are connected to end nodes, and others of the N ports are connected to other edge switches in the same sub-network plane, other of the N ports are connected to at least one of the global switches.

  5. Fabrication and characterisation of fabric supercapacitor

    OpenAIRE

    Yong, Sheng

    2016-01-01

    Fabric supercapacitor is a flexible electrochemical device for energy storage application. It is designed to power up flexible electronic systems used for, for example, information sensing, data computation and communication. The development of a flexible supercapacitor is important for e-textiles since supercapacitor can achieve higher energy density than a standard parallel plate capacitor and a larger power density compared with a battery. This research area is currently facing barriers on...

  6. Isolated converter with synchronized switching leg

    NARCIS (Netherlands)

    2003-01-01

    An amplification device is disclosed providing a way of integrating a switch mode power supply and a class D amplifier (switch mode amplifier). This results in the usage of basically one magnetic component (1), one major energy storage element (4) and switches (20, 30) that are controlled in such a

  7. Mechanism of single atom switch on silicon

    DEFF Research Database (Denmark)

    Quaade, Ulrich; Stokbro, Kurt; Thirstrup, C.

    1998-01-01

    We demonstrate single atom switch on silicon which operates by displacement of a hydrogen atom on the silicon (100) surface at room temperature. We find two principal effects by which the switch is controlled: a pronounced maximum of the switching probability as function of sample bias...

  8. A CW Gunn diode bistable switching element.

    Science.gov (United States)

    Hurtado, M.; Rosenbaum, F. J.

    1972-01-01

    Experiments with a current-controlled bistable switching element using a CW Gunn diode are reported. Switching rates of the order of 10 MHz have been obtained. Switching is initiated by current pulses of short duration (5-10 ns). Rise times of the order of several nanoseconds could be obtained.

  9. A gain-coefficient switched Alexandrite laser

    International Nuclear Information System (INIS)

    Lee, Chris J; Van der Slot, Peter J M; Boller, Klaus-J

    2013-01-01

    We report on a gain-coefficient switched Alexandrite laser. An electro-optic modulator is used to switch between high and low gain states by making use of the polarization dependent gain of Alexandrite. In gain-coefficient switched mode, the laser produces 85 ns pulses with a pulse energy of 240 mJ at a repetition rate of 5 Hz.

  10. 47 CFR 69.106 - Local switching.

    Science.gov (United States)

    2010-10-01

    ... foreign services that use local exchange switching facilities. (c) If end users of an interstate or... local exchange carriers shall establish rate elements for local switching as follows: (1) Price cap... use local exchange switching facilities for the provision of interstate or foreign services. The...

  11. Caffeine improves anticipatory processes in task switching

    NARCIS (Netherlands)

    Tieges, Zoe; Snel, Jan; Kok, Albert; Wijnen, Jasper G.; Lorist, Monicque M.; Ridderinkhof, K. Richard

    We studied the effects of moderate amounts of caffeine on task switching and task maintenance using mixed-task (AABB) blocks, in which participants alternated predictably between two tasks, and single-task (AAAA, BBBB) blocks. Switch costs refer to longer reaction times (RT) on task switch trials

  12. Bootstrapped Low-Voltage Analog Switches

    DEFF Research Database (Denmark)

    Steensgaard-Madsen, Jesper

    1999-01-01

    Novel low-voltage constant-impedance analog switch circuits are proposed. The switch element is a single MOSFET, and constant-impedance operation is obtained using simple circuits to adjust the gate and bulk voltages relative to the switched signal. Low-voltage (1-volt) operation is made feasible...

  13. Control and synchronisation in switched arrival systems

    NARCIS (Netherlands)

    Rem, B.; Armbruster, H.D.

    2003-01-01

    A chaotic model of a production flow called the switched arrival system is extended to include switching times and maintenance. The probability distribution of the chaotic return times is calculated. Scheduling maintenance, loss of production due to switching, and control of the chaotic dynamics is

  14. Schottky barrier MOSFET systems and fabrication thereof

    Science.gov (United States)

    Welch, J.D.

    1997-09-02

    (MOS) device systems-utilizing Schottky barrier source and drain to channel region junctions are disclosed. Experimentally derived results which demonstrate operation of fabricated N-channel and P-channel Schottky barrier (MOSFET) devices, and of fabricated single devices with operational characteristics similar to (CMOS) and to a non-latching (SRC) are reported. Use of essentially non-rectifying Schottky barriers in (MOS) structures involving highly doped and the like and intrinsic semiconductor to allow non-rectifying interconnection of, and electrical accessing of device regions is also disclosed. Insulator effected low leakage current device geometries and fabrication procedures therefore are taught. Selective electrical interconnection of drain to drain, source to drain, or source to source, of N-channel and/or P-channel Schottky barrier (MOSFET) devices formed on P-type, N-type and Intrinsic semiconductor allows realization of Schottky Barrier (CMOS), (MOSFET) with (MOSFET) load, balanced differential (MOSFET) device systems and inverting and non-inverting single devices with operating characteristics similar to (CMOS), which devices can be utilized in modulation, as well as in voltage controlled switching and effecting a direction of rectification. 89 figs.

  15. Junction and circuit fabrication

    International Nuclear Information System (INIS)

    Jackel, L.D.

    1980-01-01

    Great strides have been made in Josephson junction fabrication in the four years since the first IC SQUID meeting. Advances in lithography have allowed the production of devices with planar dimensions as small as a few hundred angstroms. Improved technology has provided ultra-high sensitivity SQUIDS, high-efficiency low-noise mixers, and complex integrated circuits. This review highlights some of the new fabrication procedures. The review consists of three parts. Part 1 is a short summary of the requirements on junctions for various applications. Part 2 reviews intergrated circuit fabrication, including tunnel junction logic circuits made at IBM and Bell Labs, and microbridge radiation sources made at SUNY at Stony Brook. Part 3 describes new junction fabrication techniques, the major emphasis of this review. This part includes a discussion of small oxide-barrier tunnel junctions, semiconductor barrier junctions, and microbridge junctions. Part 3 concludes by considering very fine lithography and limitations to miniaturization. (orig.)

  16. Construction, fabrication, and installation

    International Nuclear Information System (INIS)

    1992-05-01

    This standard specifies the construction, fabrication, and installation requirements that apply to concrete containment structures of a containment system designated as class containment components, parts and appurtenances for nuclear power plants

  17. Experimental Fabrication Facility

    Data.gov (United States)

    Federal Laboratory Consortium — Provides aviation fabrication support to special operations aircraft residing at Fort Eustis and other bases in the United States. Support is also provided to AATD...

  18. Alloy Fabrication Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — At NETL’s Alloy Fabrication Facility in Albany, OR, researchers conduct DOE research projects to produce new alloys suited to a variety of applications, from gas...

  19. A Shape Memory Alloy Based Cryogenic Thermal Conduction Switch

    Science.gov (United States)

    Notardonato, W. U.; Krishnan, V. B.; Singh, J. D.; Woodruff, T. R.; Vaidyanathan, R.

    2005-01-01

    Shape memory alloys (SMAs) can produce large strains when deformed (e.g., up to 8%). Heating results in a phase transformation and associated recovery of all the accumulated strain. This strain recovery can occur against large forces, resulting in their use as actuators. Thus an SMA element can integrate both sensory and actuation functions, by inherently sensing a change in temperature and actuating by undergoing a shape change as a result of a temperature-induced phase transformation. Two aspects of our work on cryogenic SMAs are addressed here. First - a shape memory alloy based cryogenic thermal conduction switch for operation between dewars of liquid methane and liquid oxygen in a common bulkhead arrangement is discussed. Such a switch integrates the sensor element and the actuator element and can be used to create a variable thermal sink to other cryogenic tanks for liquefaction, densification, and zero boil-off systems for advanced spaceport applications. Second - fabrication via arc-melting and subsequent materials testing of SMAs with cryogenic transformation temperatures for use in the aforementioned switch is discussed.

  20. A Shape Memory Alloy Based Cryogenic Thermal Conduction Switch

    International Nuclear Information System (INIS)

    Krishnan, V.B.; Singh, J.D.; Woodruff, T.R.; Vaidyanathan, R.; Notardonato, W.U.

    2004-01-01

    Shape memory alloys (SMAs) can produce large strains when deformed (e.g., up to 8%). Heating results in a phase transformation and associated recovery of all the accumulated strain. This strain recovery can occur against large forces, resulting in their use as actuators. Thus an SMA element can integrate both sensory and actuation functions, by inherently sensing a change in temperature and actuating by undergoing a shape change as a result of a temperature-induced phase transformation. Two aspects of our work on cryogenic SMAs are addressed here. First - a shape memory alloy based cryogenic thermal conduction switch for operation between dewars of liquid methane and liquid oxygen in a common bulkhead arrangement is discussed. Such a switch integrates the sensor element and the actuator element and can be used to create a variable thermal sink to other cryogenic tanks for liquefaction, densification, and zero boil-off systems for advanced spaceport applications. Second - fabrication via arc-melting and subsequent materials testing of SMAs with cryogenic transformation temperatures for use in the aforementioned switch is discussed

  1. A dual-stimuli-responsive fluorescent switch ultrathin film

    Science.gov (United States)

    Li, Zhixiong; Liang, Ruizheng; Liu, Wendi; Yan, Dongpeng; Wei, Min

    2015-10-01

    Stimuli-responsive fluorescent switches have shown broad applications in optical devices, biological materials and intelligent responses. Herein, we describe the design and fabrication of a dual-stimuli-responsive fluorescent switch ultrathin film (UTF) via a three-step layer-by-layer (LBL) technique: (i) encapsulation of spiropyran (SP) within an amphiphilic block copolymer (PTBEM) to give the (SP@PTBEM) micelle; (ii) the mixture of riboflavin (Rf) and poly(styrene 4-sulfonate) (PSS) to enhance the adhesion ability of small molecules; (iii) assembly of negatively charged SP@PTBEM and Rf-PSS with cationic layered double hydroxide (LDH) nanoplatelets to obtain the (Rf-PSS/LDH/SP@PTBEM)n UTFs (n: bilayer number). The assembly process of the UTFs and their luminescence properties, as monitored by fluorescence spectroscopy and scanning electron microscopy (SEM), present a uniform and ordered layered structure with stepwise growth. The resulting Rf-PSS/LDH/SP@PTBEM UTF serves as a three-state switchable multicolor (green, yellow, and red) luminescent system based on stimulation from UV/Vis light and pH, with an acceptable reversibility. Therefore, this work provides a facile way to fabricate stimuli-responsive solid-state film switches with tunable-color luminescence, which have potential applications in the areas of displays, sensors, and rewritable optical memory and fluorescent logic devices.Stimuli-responsive fluorescent switches have shown broad applications in optical devices, biological materials and intelligent responses. Herein, we describe the design and fabrication of a dual-stimuli-responsive fluorescent switch ultrathin film (UTF) via a three-step layer-by-layer (LBL) technique: (i) encapsulation of spiropyran (SP) within an amphiphilic block copolymer (PTBEM) to give the (SP@PTBEM) micelle; (ii) the mixture of riboflavin (Rf) and poly(styrene 4-sulfonate) (PSS) to enhance the adhesion ability of small molecules; (iii) assembly of negatively charged SP

  2. Fabricating nuclear components

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Activities of the Nuclear Engineering Division of Vickers Ltd., particularly fabrication of long slim tubular components for power reactors and the construction of irradiation loops and rigs, are outlined. The processes include hydraulic forming for fabrication of various types of tubes and outer cases of fuel transfer buckets, various specialised welding operations including some applications of the TIG process, and induction brazing of specialised assemblies. (U.K.)

  3. Nuclear Fabrication Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Levesque, Stephen [EWI, Columbus, OH (United States)

    2013-04-05

    This report summarizes the activities undertaken by EWI while under contract from the Department of Energy (DOE) Office of Nuclear Energy (NE) for the management and operation of the Nuclear Fabrication Consortium (NFC). The NFC was established by EWI to independently develop, evaluate, and deploy fabrication approaches and data that support the re-establishment of the U.S. nuclear industry: ensuring that the supply chain will be competitive on a global stage, enabling more cost-effective and reliable nuclear power in a carbon constrained environment. The NFC provided a forum for member original equipment manufactures (OEM), fabricators, manufacturers, and materials suppliers to effectively engage with each other and rebuild the capacity of this supply chain by : Identifying and removing impediments to the implementation of new construction and fabrication techniques and approaches for nuclear equipment, including system components and nuclear plants. Providing and facilitating detailed scientific-based studies on new approaches and technologies that will have positive impacts on the cost of building of nuclear plants. Analyzing and disseminating information about future nuclear fabrication technologies and how they could impact the North American and the International Nuclear Marketplace. Facilitating dialog and initiate alignment among fabricators, owners, trade associations, and government agencies. Supporting industry in helping to create a larger qualified nuclear supplier network. Acting as an unbiased technology resource to evaluate, develop, and demonstrate new manufacturing technologies. Creating welder and inspector training programs to help enable the necessary workforce for the upcoming construction work. Serving as a focal point for technology, policy, and politically interested parties to share ideas and concepts associated with fabrication across the nuclear industry. The report the objectives and summaries of the Nuclear Fabrication Consortium

  4. Design and realization of a tactile switches module with capacitive sensing method implemented with a microcontroller

    Directory of Open Access Journals (Sweden)

    Lorenzo Capineri

    2016-08-01

    Full Text Available The aim of this research project is the architecture and the design of an electronic system for controlling domestic tactile switches to be integrated into a home automation system based on the KNX standard. All the steps that led to the fulfillment of the finished prototype are reported, from the study and design of the capacitive tactile sensors and the electronic control board according to the specifications imposed by KNX standard. The touch event detection is reached as a trade-off with the footprint requirements of the switch. Experimental results of the fabricated prototype are presented to demonstrate the feasibility of this device.

  5. High-speed electro-optic switch with -80 dB crosstalk

    Science.gov (United States)

    Pan, J. J.; Su, W. H.; Xu, J. Y.; Grove, C. H.

    1992-01-01

    Special device modeling, design and layout, and precision processing controls were employed to fabricate new balanced-bridge 2x2 and 4x4 switches on X-cut, Y-propagation LiNbO3 substrate using Ti indiffused optical waveguides. The best of these devices achieved extinction ratio and crosstalk isolation of better than 93 dB electrically (46.5 dB optically). The new switches demonstrate good reproducibility with electrical crosstalk less than -80 dB.

  6. Atmel Microcontroller Based Soft Switched PWM ZVS Full Bridge DC to DC Converter

    Directory of Open Access Journals (Sweden)

    DEEPAK KUMAR NAYAK

    2010-12-01

    Full Text Available This paper deals with the simulation and implementation of soft switched PWM ZVS full bridge DC to DC converter. The 48V DC is efficiently reduced to 12V DC using a DC to DC converter. This converter has advantages like reduced switching losses, stresses and EMI. Input DC is converted into high frequency AC and it is stepped down to 12V level. Later it is rectified using a full wave rectifier. Laboratory model of microcontroller based DC to DC converter is fabricated and tested. The experimental results are compared with the simulation results.

  7. Optimization of multi-branch switched diversity systems

    KAUST Repository

    Nam, Haewoon; Alouini, Mohamed-Slim

    2009-01-01

    A performance optimization based on the optimal switching threshold(s) for a multi-branch switched diversity system is discussed in this paper. For the conventional multi-branch switched diversity system with a single switching threshold

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

    Science.gov (United States)

    Cooper, James A.

    1986-01-01

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

  9. Resistive Switching of Ta2O5-Based Self-Rectifying Vertical-Type Resistive Switching Memory

    Science.gov (United States)

    Ryu, Sungyeon; Kim, Seong Keun; Choi, Byung Joon

    2018-01-01

    To efficiently increase the capacity of resistive switching random-access memory (RRAM) while maintaining the same area, a vertical structure similar to a vertical NAND flash structure is needed. In addition, the sneak-path current through the half-selected neighboring memory cell should be mitigated by integrating a selector device with each RRAM cell. In this study, an integrated vertical-type RRAM cell and selector device was fabricated and characterized. Ta2O5 as the switching layer and TaOxNy as the selector layer were used to preliminarily study the feasibility of such an integrated device. To make the side contact of the bottom electrode with active layers, a thick Al2O3 insulating layer was placed between the Pt bottom electrode and the Ta2O5/TaOxNy stacks. Resistive switching phenomena were observed under relatively low currents (below 10 μA) in this vertical-type RRAM device. The TaOxNy layer acted as a nonlinear resistor with moderate nonlinearity. Its low-resistance-state and high-resistance-state were well retained up to 1000 s.

  10. Large aperture optical switching devices

    International Nuclear Information System (INIS)

    Goldhar, J.; Henesian, M.A.

    1983-01-01

    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. Shape memory thermal conduction switch

    Science.gov (United States)

    Vaidyanathan, Rajan (Inventor); Krishnan, Vinu (Inventor); Notardonato, William U. (Inventor)

    2010-01-01

    A thermal conduction switch includes a thermally-conductive first member having a first thermal contacting structure for securing the first member as a stationary member to a thermally regulated body or a body requiring thermal regulation. A movable thermally-conductive second member has a second thermal contacting surface. A thermally conductive coupler is interposed between the first member and the second member for thermally coupling the first member to the second member. At least one control spring is coupled between the first member and the second member. The control spring includes a NiTiFe comprising shape memory (SM) material that provides a phase change temperature <273 K, a transformation range <40 K, and a hysteresis of <10 K. A bias spring is between the first member and the second member. At the phase change the switch provides a distance change (displacement) between first and second member by at least 1 mm, such as 2 to 4 mm.

  12. Negation switching invariant signed graphs

    Directory of Open Access Journals (Sweden)

    Deepa Sinha

    2014-04-01

    Full Text Available A signed graph (or, $sigraph$ in short is a graph G in which each edge x carries a value $\\sigma(x \\in \\{-, +\\}$ called its sign. Given a sigraph S, the negation $\\eta(S$ of the sigraph S is a sigraph obtained from S by reversing the sign of every edge of S. Two sigraphs $S_{1}$ and $S_{2}$ on the same underlying graph are switching equivalent if it is possible to assign signs `+' (`plus' or `-' (`minus' to vertices of $S_{1}$ such that by reversing the sign of each of its edges that has received opposite signs at its ends, one obtains $S_{2}$. In this paper, we characterize sigraphs which are negation switching invariant and also see for what sigraphs, S and $\\eta (S$ are signed isomorphic.

  13. Switch for Good Community Program

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, Tabitha [Balfour Beatty Military Housing Management LLC, Newtown Square, PA (United States); Amran, Martha [WattzOn, Inc., Mountain View, CA (United States)

    2013-11-19

    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. The program was delivered on-time and on-budget, and its success is based on the teamwork of local BB staff and the WattzOn team. The following graphic shows Switch4Good “by the numbers”, e.g. the scale of operations achieved during Phase I.

  14. Pulsed laser triggered high speed microfluidic switch

    Science.gov (United States)

    Wu, Ting-Hsiang; Gao, Lanyu; Chen, Yue; Wei, Kenneth; Chiou, Pei-Yu

    2008-10-01

    We report a high-speed microfluidic switch capable of achieving a switching time of 10 μs. The switching mechanism is realized by exciting dynamic vapor bubbles with focused laser pulses in a microfluidic polydimethylsiloxane (PDMS) channel. The bubble expansion deforms the elastic PDMS channel wall and squeezes the adjacent sample channel to control its fluid and particle flows as captured by the time-resolved imaging system. A switching of polystyrene microspheres in a Y-shaped channel has also been demonstrated. This ultrafast laser triggered switching mechanism has the potential to advance the sorting speed of state-of-the-art microscale fluorescence activated cell sorting devices.

  15. Secure videoconferencing equipment switching system and method

    Science.gov (United States)

    Hansen, Michael E [Livermore, CA

    2009-01-13

    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.

  16. Switching strategies to optimize search

    International Nuclear Information System (INIS)

    Shlesinger, Michael F

    2016-01-01

    Search strategies are explored when the search time is fixed, success is probabilistic and the estimate for success can diminish with time if there is not a successful result. Under the time constraint the problem is to find the optimal time to switch a search strategy or search location. Several variables are taken into account, including cost, gain, rate of success if a target is present and the probability that a target is present. (paper: interdisciplinary statistical mechanics)

  17. Correlated randomness and switching phenomena

    Science.gov (United States)

    Stanley, H. E.; Buldyrev, S. V.; Franzese, G.; Havlin, S.; Mallamace, F.; Kumar, P.; Plerou, V.; Preis, T.

    2010-08-01

    One challenge of biology, medicine, and economics is that the systems treated by these serious scientific disciplines have no perfect metronome in time and no perfect spatial architecture-crystalline or otherwise. Nonetheless, as if by magic, out of nothing but randomness one finds remarkably fine-tuned processes in time and remarkably fine-tuned structures in space. Further, many of these processes and structures have the remarkable feature of “switching” from one behavior to another as if by magic. The past century has, philosophically, been concerned with placing aside the human tendency to see the universe as a fine-tuned machine. Here we will address the challenge of uncovering how, through randomness (albeit, as we shall see, strongly correlated randomness), one can arrive at some of the many spatial and temporal patterns in biology, medicine, and economics and even begin to characterize the switching phenomena that enables a system to pass from one state to another. Inspired by principles developed by A. Nihat Berker and scores of other statistical physicists in recent years, we discuss some applications of correlated randomness to understand switching phenomena in various fields. Specifically, we present evidence from experiments and from computer simulations supporting the hypothesis that water’s anomalies are related to a switching point (which is not unlike the “tipping point” immortalized by Malcolm Gladwell), and that the bubbles in economic phenomena that occur on all scales are not “outliers” (another Gladwell immortalization). Though more speculative, we support the idea of disease as arising from some kind of yet-to-be-understood complex switching phenomenon, by discussing data on selected examples, including heart disease and Alzheimer disease.

  18. Fast superconducting magnetic field switch

    Science.gov (United States)

    Goren, Yehuda; Mahale, Narayan K.

    1996-01-01

    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.

  19. Fast superconducting magnetic field switch

    International Nuclear Information System (INIS)

    Goren, Y.; Mahale, N.K.

    1996-01-01

    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. 6 figs

  20. Coating possibilities for magnetic switches

    International Nuclear Information System (INIS)

    Sharp, D.J.; Harjes, H.C.; Mann, G.A.; Morgan, F.A.

    1990-01-01

    High average power magnetic pulse compression systems are now being considered for use in several applications such as the High Power Radiation Source (HiPoRS) project. Such systems will require high reliability magnetic switches (saturable inductors) that are very efficient and have long lifetimes. One of the weakest components in magnetic switches is their interlaminar insulation. Considerations related to dielectric breakdown, thermal management of compact designs, and economical approaches for achieving these needs must be addressed. Various dielectric insulation and coating materials have been applied to Metglas foil in an attempt to solve the complex technical and practical problems associated with large magnetic switch structures. This work reports various needs, studies, results, and proposals in selecting and evaluating continuous coating approaches for magnetic foil. Techniques such as electrophoretic polymer deposition and surface chemical oxidation are discussed. We also propose continuous photofabrication processes for applying dielectric ribs or spacers to the foil which permit circulation of dielectric liquids for cooling during repetitive operation. 10 refs., 8 figs., 11 tabs

  1. Analytical Performance Evaluation of Different Switch Solutions

    Directory of Open Access Journals (Sweden)

    Francisco Sans

    2013-01-01

    Full Text Available The virtualization of the network access layer has opened new doors in how we perceive networks. With this virtualization of the network, it is possible to transform a regular PC with several network interface cards into a switch. PC-based switches are becoming an alternative to off-the-shelf switches, since they are cheaper. For this reason, it is important to evaluate the performance of PC-based switches. In this paper, we present a performance evaluation of two PC-based switches, using Open vSwitch and LiSA, and compare their performance with an off-the-shelf Cisco switch. The RTT, throughput, and fairness for UDP are measured for both Ethernet and Fast Ethernet technologies. From this research, we can conclude that the Cisco switch presents the best performance, and both PC-based switches have similar performance. Between Open vSwitch and LiSA, Open vSwitch represents a better choice since it has more features and is currently actively developed.

  2. Streamer model for high voltage water switches

    International Nuclear Information System (INIS)

    Sazama, F.J.; Kenyon, V.L. III

    1979-01-01

    An electrical switch model for high voltage water switches has been developed which predicts streamer-switching effects that correlate well with water-switch data from Casino over the past four years and with switch data from recent Aurora/AMP experiments. Preclosure rounding and postclosure resistive damping of pulseforming line voltage waveforms are explained in terms of spatially-extensive, capacitive-coupling of the conducting streamers as they propagate across the gap and in terms of time-dependent streamer resistance and inductance. The arc resistance of the Casino water switch and of a gas switch under test on Casino was determined by computer fit to be 0.5 +- 0.1 ohms and 0.3 +- 0.06 ohms respectively, during the time of peak current in the power pulse. Energy lost in the water switch during the first pulse is 18% of that stored in the pulseforming line while similar energy lost in the gas switch is 11%. The model is described, computer transient analyses are compared with observed water and gas switch data and the results - switch resistance, inductance and energy loss during the primary power pulse - are presented

  3. Optical Multidimensional Switching for Data Center Networks

    DEFF Research Database (Denmark)

    Kamchevska, Valerija

    2017-01-01

    . Software controlled switching using an on-chip integrated fiber switch is demonstrated and enabling of additional network functionalities such as multicast and optical grooming is experimentally confirmed. Altogether this work demonstrates the potential of optical switching technologies...... for the purpose of deploying optical switching within the network. First, the Hi-Ring data center architecture is proposed. It is based on optical multidimensional switching nodes that provide switching in hierarchically layered space, wavelength and time domain. The performance of the Hi-Ring architecture...... is evaluated experimentally and successful switching of both high capacity wavelength connections and time-shared subwavelengthconnections is demonstrated. Error-free performance is also achieved when transmitting 7 Tbit/s using multicore fiber, confirming the ability to scale the network. Moreover...

  4. Pinning Synchronization of Switched Complex Dynamical Networks

    Directory of Open Access Journals (Sweden)

    Liming Du

    2015-01-01

    Full Text Available Network topology and node dynamics play a key role in forming synchronization of complex networks. Unfortunately there is no effective synchronization criterion for pinning synchronization of complex dynamical networks with switching topology. In this paper, pinning synchronization of complex dynamical networks with switching topology is studied. Two basic problems are considered: one is pinning synchronization of switched complex networks under arbitrary switching; the other is pinning synchronization of switched complex networks by design of switching when synchronization cannot achieved by using any individual connection topology alone. For the two problems, common Lyapunov function method and single Lyapunov function method are used respectively, some global synchronization criteria are proposed and the designed switching law is given. Finally, simulation results verify the validity of the results.

  5. Synchronization in complex networks with switching topology

    International Nuclear Information System (INIS)

    Wang, Lei; Wang, Qing-guo

    2011-01-01

    This Letter investigates synchronization issues of complex dynamical networks with switching topology. By constructing a common Lyapunov function, we show that local and global synchronization for a linearly coupled network with switching topology can be evaluated by the time average of second smallest eigenvalues corresponding to the Laplacians of switching topology. This result is quite powerful and can be further used to explore various switching cases for complex dynamical networks. Numerical simulations illustrate the effectiveness of the obtained results in the end. -- Highlights: → Synchronization of complex networks with switching topology is investigated. → A common Lyapunov function is established for synchronization of switching network. → The common Lyapunov function is not necessary to monotonically decrease with time. → Synchronization is determined by the second smallest eigenvalue of its Laplacian. → Synchronization criterion can be used to investigate various switching cases.

  6. Energy storage, compression, and switching. Vol. 2

    International Nuclear Information System (INIS)

    Nardi, V.; Bostick, W.H.; Sahlin, H.

    1983-01-01

    This book is a compilation of papers presented at the Second International Conference on Energy Storage, Compression, and Switching, which was held in order to assemble active researchers with a major interest in plasma physics, electron beams, electric and magnetic energy storage systems, high voltage and high current switches, free-electron lasers, and pellet implosion plasma focus. Topics covered include: Slow systems: 50-60 Hz machinery, homopolar generators, slow capacitors, inductors, and solid state switches; Intermediate systems: fast capacitor banks; superconducting storage and switching; gas, vacuum, and dielectric switching; nonlinear (magnetic) switching; imploding liners capacitors; explosive generators; and fuses; and Fast systems: Marx, Blumlein, oil, water, and pressurized water dielectrics; switches; magnetic insulation; electron beams; and plasmas

  7. Micro optical fiber display switch based on the magnetohydrodynamic (MHD) principle

    Science.gov (United States)

    Lian, Kun; Heng, Khee-Hang

    2001-09-01

    This paper reports on a research effort to design, microfabricate and test an optical fiber display switch based on magneto hydrodynamic (MHD) principal. The switch is driven by the Lorentz force and can be used to turn on/off the light. The SU-8 photoresist and UV light source were used for prototype fabrication in order to lower the cost. With a magnetic field supplied by an external permanent magnet, and a plus electrical current supplied across the two inert sidewall electrodes, the distributed body force generated will produce a pressure difference on the fluid mercury in the switch chamber. By change the direction of current flow, the mercury can turn on or cut off the light pass in less than 10 ms. The major advantages of a MHD-based micro-switch are that it does not contain any solid moving parts and power consumption is much smaller comparing to the relay type switches. This switch can be manufactured by molding gin batch production and may have potential applications in extremely bright traffic control,, high intensity advertising display, and communication.

  8. Resistive Switching and Voltage Induced Modulation of Tunneling Magnetoresistance in Nanosized Perpendicular Organic Spin Valves

    Science.gov (United States)

    Schmidt, Georg; Goeckeritz, Robert; Homonnay, Nico; Mueller, Alexander; Fuhrmann, Bodo

    Resistive switching has already been reported in organic spin valves (OSV), however, its origin is still unclear. We have fabricated nanosized OSV based on La0.7Sr0.3MnO3/Alq3/Co. These devices show fully reversible resistive switching of up to five orders of magnitude. The magnetoresistance (MR) is modulated during the switching process from negative (-70%) to positive values (+23%). The results are reminiscent of experiments claiming magnetoelectric coupling in LSMO based tunneling structures using ferroelectric barriers. By analyzing the I/V characteristics of the devices we can show that transport is dominated by tunneling through pinholes. The resistive switching is caused by voltage induced creation and motion of oxygen vacancies at the LSMO surface, however, the resulting tunnel barrier is complemented by a second adjacent barrier in the organic semiconductor. Our model shows that the barrier in the organic material is constant, causing the initial MR while the barrier in the LMSO can be modulated by the voltage resulting in the resistive switching and the modulation of the MR as the coupling to the states in the LSMO changes. A switching caused by LSMO only is also supported by the fact that replacing ALQ3 by H2PC yields almost identical results. Supported by the DFG in the SFB762.

  9. Ka-Band, MEMS Switched Line Phase Shifters Implemented in Finite Ground Coplanar Waveguide

    Science.gov (United States)

    Scardelletti, Maximilian C.; Ponchak, George E.; Varaljay, Nicholas C.

    2005-01-01

    Ka-band MEMS switched line phase shifters implemented in finite ground coplanar waveguide are described in this paper. The phase shifters are constructed of single-pole double-throw (SPDT) switches with additional reference and phase offset transmission line lengths. The one- and two-bit phase shifters are fabricated on high resistivity (HR) silicon with a dielectric constant, Epsilon(sub T) = 11.7 and a substrate thickness, t = 500microns. The switching architectures integrated within the phase shifters consist of MEMS switches that are doubly anchored cantilever beam capacitive switches with additional high inductive sections (MEMS LC device). The SPDT switch is composed of a T-junction with a MEMS LC device at each output port. The one-bit phase shifter described in this paper has an insertion loss (IL) and return loss (RL) of 0.9 dB and 30 dB while the two-bit described has an IL and RL of 1.8 dB and 30 dB respectively. The one-bit phase shifter's designed offset phase is 22.5deg and actual measured phase shift is 21.8deg. The two-bit phase shifter's designed offset phase is 22.5deg, 45deg, and 67.5deg and the actual measured phase shifts are 21.4deg, 44.2deg, and 65.8deg, respectively.

  10. Design and Simulation of an RF-MEMS Switch and analysis of its Electromagnetic aspect in realtion to stress

    Directory of Open Access Journals (Sweden)

    Amna Riaz

    2018-01-01

    Full Text Available Microelectromechanical Systems (MEMS are devices made up of several electrical and mechanical components. They consist of mechanical functions (sensing, thermal, inertial and electrical functions (switching, decision making on a single chip made by microfabrication methods. These chips exhibit combined properties of the two functions. The size of system has characteristic dimensions less than 1mm but more than 1μm. The configuration of these components determine the final deliverables of the switch. MEMS can be designed to meet user requirements on any level from microbiological application such as biomedical transducers or tissue engineering, to mechanical systems such as microfluidic diagnoses or chemical fuel cells. The low cost, small mass and minimal power consumption of the MEMS makes it possible to readily integrate to any kind of system in any environment. MEMS are faster, better and cheaper. They offer excellent electrical performances. MEMS working at Radio frequencies are RF MEMS. RF-MEMS switches find huge market in the modern telecommunication networks, biological, automobiles, satellites and defense systems because of their lower power consumptions at relatively higher frequencies and better electrical performances. But the reliability is the major hurdle in the fate of RF MEMS switches. Reliability mainly arises due to the presence of residual stresses, charging current, fatigue and creep and contact degradation. The presence of residual stresses in switches the S-Parameters of the switches are affected badly and the residual stress affects the final planarity of the fabricated structure. Design and simulation of an RF-MEMS switch is proposed considering the residual stresses in both on and off state. The operating frequency band is being optimized and the best possible feasible fabrication technique for the proposed switch design is being analyzed. S-Parameters are calculated and a comparison for the switches with stress and

  11. Optical Microresonators Theory, Fabrication, and Applications

    CERN Document Server

    Heebner, John; Ibrahim, Tarek

    2008-01-01

    This book explains why microresonators came to be important components in the photonic toolbox. While functionally similar to the Fabry-Perot, microring resonators offer a planar nature which is naturally compatible with monolithic microfabrication technologies. In these chapters lie the principles required to characterize, design, construct, and implement microresonators as lasers, amplifiers, sensors, filters, demultiplexers, switches, routers, and logic gates. Additionally, much like quantum dots and photonic crystals, it will be shown how microresonators offer an alternative method for creating engineerable materials with designer linear and nonlinear responses tailored for advanced functionalities operating at ultrafast speeds and compact scales. This is the first detailed text on the theory, fabrication, and applications of optical microresonators, and will be found useful by both graduate students and researchers. With an emphasis on building intuition with distilled equations and graphical illustratio...

  12. Understanding core conductor fabrics

    International Nuclear Information System (INIS)

    Swenson, D E

    2011-01-01

    ESD Association standard test method ANSI/ESD STM2.1 - Garments (STM2.1), provides electrical resistance test procedures that are applicable for materials and garments that have surface conductive or surface dissipative properties. As has been reported in other papers over the past several years 1 fabrics are now used in many industries for electrostatic control purposes that do not have surface conductive properties and therefore cannot be evaluated using the procedures in STM2.1 2 . A study was conducted to compare surface conductive fabrics with samples of core conductor fibre based fabrics in order to determine differences and similarities with regards to various electrostatic properties. This work will be used to establish a new work item proposal within WG-2, Garments, in the ESD Association Standards Committee in the USA.

  13. Enhancement of resistive switching properties in Al2O3 bilayer-based atomic switches: multilevel resistive switching

    Science.gov (United States)

    Vishwanath, Sujaya Kumar; Woo, Hyunsuk; Jeon, Sanghun

    2018-06-01

    Atomic switches are considered to be building blocks for future non-volatile data storage and internet of things. However, obtaining device structures capable of ultrahigh density data storage, high endurance, and long data retention, and more importantly, understanding the switching mechanisms are still a challenge for atomic switches. Here, we achieved improved resistive switching performance in a bilayer structure containing aluminum oxide, with an oxygen-deficient oxide as the top switching layer and stoichiometric oxide as the bottom switching layer, using atomic layer deposition. This bilayer device showed a high on/off ratio (105) with better endurance (∼2000 cycles) and longer data retention (104 s) than single-oxide layers. In addition, depending on the compliance current, the bilayer device could be operated in four different resistance states. Furthermore, the depth profiles of the hourglass-shaped conductive filament of the bilayer device was observed by conductive atomic force microscopy.

  14. Fabrication of multilayer nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Jasveer, E-mail: kaurjasveer89@gmail.com; Singh, Avtar; Kumar, Davinder [Department of Physics, Punjabi University Patiala, 147002, Punjab (India); Thakur, Anup; Kaur, Raminder, E-mail: raminder-k-saini@yahoo.com [Department of Basic and Applied Sciences, Punjabi University Patiala, 147002, Punjab (India)

    2016-05-06

    Multilayer nanowires were fabricated by potentiostate ectrodeposition template synthesis method into the pores of polycarbonate membrane. In present work layer by layer deposition of two different metals Ni and Cu in polycarbonate membrane having pore size of 600 nm were carried out. It is found that the growth of nanowires is not constant, it varies with deposition time. Scanning electron microscopy (SEM) is used to study the morphology of fabricated multilayer nanowires. An energy dispersive X-ray spectroscopy (EDS) results confirm the composition of multilayer nanowires. The result shows that multilayer nanowires formed is dense.

  15. MOX Fabrication Isolation Considerations

    Energy Technology Data Exchange (ETDEWEB)

    Eric L. Shaber; Bradley J Schrader

    2005-08-01

    This document provides a technical position on the preferred level of isolation to fabricate demonstration quantities of mixed oxide transmutation fuels. The Advanced Fuel Cycle Initiative should design and construct automated glovebox fabrication lines for this purpose. This level of isolation adequately protects the health and safety of workers and the general public for all mixed oxide (and other transmutation fuel) manufacturing efforts while retaining flexibility, allowing parallel development and setup, and minimizing capital expense. The basis regulations, issues, and advantages/disadvantages of five potential forms of isolation are summarized here as justification for selection of the preferred technical position.

  16. Fabrication of multilayer nanowires

    International Nuclear Information System (INIS)

    Kaur, Jasveer; Singh, Avtar; Kumar, Davinder; Thakur, Anup; Kaur, Raminder

    2016-01-01

    Multilayer nanowires were fabricated by potentiostate ectrodeposition template synthesis method into the pores of polycarbonate membrane. In present work layer by layer deposition of two different metals Ni and Cu in polycarbonate membrane having pore size of 600 nm were carried out. It is found that the growth of nanowires is not constant, it varies with deposition time. Scanning electron microscopy (SEM) is used to study the morphology of fabricated multilayer nanowires. An energy dispersive X-ray spectroscopy (EDS) results confirm the composition of multilayer nanowires. The result shows that multilayer nanowires formed is dense.

  17. Resistive switching characteristics of polymer non-volatile memory devices in a scalable via-hole structure

    International Nuclear Information System (INIS)

    Kim, Tae-Wook; Choi, Hyejung; Oh, Seung-Hwan; Jo, Minseok; Wang, Gunuk; Cho, Byungjin; Kim, Dong-Yu; Hwang, Hyunsang; Lee, Takhee

    2009-01-01

    The resistive switching characteristics of polyfluorene-derivative polymer material in a sub-micron scale via-hole device structure were investigated. The scalable via-hole sub-microstructure was fabricated using an e-beam lithographic technique. The polymer non-volatile memory devices varied in size from 40 x 40 μm 2 to 200 x 200 nm 2 . From the scaling of junction size, the memory mechanism can be attributed to the space-charge-limited current with filamentary conduction. Sub-micron scale polymer memory devices showed excellent resistive switching behaviours such as a large ON/OFF ratio (I ON /I OFF ∼10 4 ), excellent device-to-device switching uniformity, good sweep endurance, and good retention times (more than 10 000 s). The successful operation of sub-micron scale memory devices of our polyfluorene-derivative polymer shows promise to fabricate high-density polymer memory devices.

  18. Electrostatic actuation and electromechanical switching behavior of one-dimensional nanostructures.

    Science.gov (United States)

    Subramanian, Arunkumar; Alt, Andreas R; Dong, Lixin; Kratochvil, Bradley E; Bolognesi, Colombo R; Nelson, Bradley J

    2009-10-27

    We report on the electromechanical actuation and switching performance of nanoconstructs involving doubly clamped, individual multiwalled carbon nanotubes. Batch-fabricated, three-state switches with low ON-state voltages (6.7 V average) are demonstrated. A nanoassembly architecture that permits individual probing of one device at a time without crosstalk from other nanotubes, which are originally assembled in parallel, is presented. Experimental investigations into device performance metrics such as hysteresis, repeatability and failure modes are presented. Furthermore, current-driven shell etching is demonstrated as a tool to tune the nanomechanical clamping configuration, stiffness, and actuation voltage of fabricated devices. Computational models, which take into account the nonlinearities induced by stress-stiffening of 1-D nanowires at large deformations, are presented. Apart from providing accurate estimates of device performance, these models provide new insights into the extension of stable travel range in electrostatically actuated nanowire-based constructs as compared to their microscale counterparts.

  19. Electron beam fabrication and characterization of high- resolution magnetic force microscopy tips

    NARCIS (Netherlands)

    Ruhrig, M.; Rührig, M.; Porthun, S.; Porthun, S.; Lodder, J.C.; Mc vitie, S.; Heyderman, L.J.; Johnston, A.B.; Chapman, J.N.

    1996-01-01

    The stray field, magnetic microstructure, and switching behavior of high‐resolution electron beam fabricated thin film tips for magnetic force microscopy (MFM) are investigated with different imaging modes in a transmission electron microscope (TEM). As the tiny smooth carbon needles covered with a

  20. Impacts of Co doping on ZnO transparent switching memory device characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Simanjuntak, Firman Mangasa; Wei, Kung-Hwa [Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu 30010, Taiwan (China); Prasad, Om Kumar [Department of Electrical Engineering and Computer Science, National Chiao Tung University, Hsinchu 30010, Taiwan (China); Panda, Debashis [Department of Electronics Engineering, National Institute of Science and Technology, Berhampur, Odisha 761008 (India); Lin, Chun-An; Tsai, Tsung-Ling; Tseng, Tseung-Yuen, E-mail: tseng@cc.nctu.edu.tw [Department of Electronics Engineering and Institute of Electronics, National Chiao Tung University, Hsinchu 30010, Taiwan (China)

    2016-05-02

    The resistive switching characteristics of indium tin oxide (ITO)/Zn{sub 1−x}Co{sub x}O/ITO transparent resistive memory devices were investigated. An appropriate amount of cobalt dopant in ZnO resistive layer demonstrated sufficient memory window and switching stability. In contrast, pure ZnO devices demonstrated a poor memory window, and using an excessive dopant concentration led to switching instability. To achieve suitable memory performance, relying only on controlling defect concentrations is insufficient; the grain growth orientation of the resistive layer must also be considered. Stable endurance with an ON/OFF ratio of more than one order of magnitude during 5000 cycles confirmed that the Co-doped ZnO device is a suitable candidate for resistive random access memory application. Additionally, fully transparent devices with a high transmittance of up to 90% at wavelength of 550 nm have been fabricated.

  1. CMOS single-stage input-powered bridge rectifier with boost switch and duty cycle control

    Science.gov (United States)

    Radzuan, Roskhatijah; Mohd Salleh, Mohd Khairul; Hamzah, Mustafar Kamal; Ab Wahab, Norfishah

    2017-06-01

    This paper presents a single-stage input-powered bridge rectifier with boost switch for wireless-powered devices such as biomedical implants and wireless sensor nodes. Realised using CMOS process technology, it employs a duty cycle switch control to achieve high output voltage using boost technique, leading to a high output power conversion. It has only six external connections with the boost inductance. The input frequency of the bridge rectifier is set at 50 Hz, while the switching frequency is 100 kHz. The proposed circuit is fabricated on a single 0.18-micron CMOS die with a space area of 0.024 mm2. The simulated and measured results show good agreement.

  2. Stable switching of resistive random access memory on the nanotip array electrodes

    KAUST Repository

    Tsai, Kun-Tong

    2016-09-13

    The formation/rupture of conducting filaments (CFs) in resistive random access memory (ReRAM) materials tune the electrical conductivities non-volatilely and are largely affected by its material composition [1], internal configurations [2] and external environments [3,4]. Therefore, controlling repetitive formation/rupture of CF as well as the spatial uniformity of formed CF are fundamentally important for improving the resistive switching (RS) performance. In this context, we have shown that by adding a field initiator, typically a textured electrode, both performance and switching uniformity of ReRAMs can be improved dramatically [5]. In addition, despite its promising characteristics, the scalable fabrication and structural homogeneity of such nanostructured electrodes are still lacking or unattainable, making miniaturization of ReRAM devices an exceeding challenge. Here, we employ nanostructured electrode (nanotip arrays, extremely uniform) formed spontaneously via a self-organized process to improve the ZnO ReRAM switching characteristics.

  3. Resistive switching in ZrO2 films: physical mechanism for filament formation and dissolution

    International Nuclear Information System (INIS)

    Parreira, Pedro; McVitie, Stephen; MacLaren, D A

    2014-01-01

    Resistive switching devices, also called memristors, have attracted much attention due to their potential memory, logic and even neuromorphic applications. Multiple physical mechanisms underpin the non-volatile switching process and are ultimately believed to give rise to the formation and dissolution of a discrete conductive filament within the active layer. However, a detailed nanoscopic analysis that fully explains all the contributory events remains to be presented. Here, we present aspects of the switching events that are correlated back to tunable details of the device fabrication process. Transmission electron microscopy and atomically resolved electron energy loss spectroscopy (EELS) studies of electrically stressed devices will then be presented, with a view to understanding the driving forces behind filament formation and dissolution

  4. Radiation-sensitive switching circuits

    Energy Technology Data Exchange (ETDEWEB)

    Moore, J.H.; Cockshott, C.P.

    1976-03-16

    A radiation-sensitive switching circuit has a light emitting diode which supplies light to a photo-transistor, the light being interrupted from time to time. When the photo-transistor is illuminated, current builds up and when this current reaches a predetermined value, a trigger circuit changes state. The peak output of the photo-transistor is measured and the trigger circuit is arranged to change state when the output of the device is a set proportion of the peak output, so as to allow for aging of the components. The circuit is designed to control the ignition system in an automobile engine.

  5. Radiation-sensitive switching circuits

    Energy Technology Data Exchange (ETDEWEB)

    Moore, J.H.; Cockshott, C.P.

    1976-03-16

    A radiation-sensitive switching circuit includes a light emitting diode which from time to time illuminates a photo-transistor, the photo-transistor serving when its output reaches a predetermined value to operate a trigger circuit. In order to allow for aging of the components, the current flow through the diode is increased when the output from the transistor falls below a known level. Conveniently, this is achieved by having a transistor in parallel with the diode, and turning the transistor off when the output from the phototransistor becomes too low. The circuit is designed to control the ignition system in an automobile engine.

  6. A switched capacitor array based system for high-speed calorimetry

    International Nuclear Information System (INIS)

    Levi, M.; Bebek, C.; Ely, R.; Jared, R.; Kipnis, I.; Kirsten, F.; Kleinfelder, S.; Merrick, T.; Milgrome, O.

    1991-12-01

    A sixteen channel analog transient recorder with 256 cells per channel has been fabricated as an integrated circuit. The circuit uses switched capacitor array technology to achieve simultaneous read/write capability and twelve bit dynamic range. Combined with highly parallel analog-to-digital converter and readout control circuitry being developed this system should satisfy the demanding electronics requirements for calorimeter detectors at the SSC. The system design and test results are presented

  7. Text-Fabric

    NARCIS (Netherlands)

    Roorda, Dirk

    2016-01-01

    Text-Fabric is a Python3 package for Text plus Annotations. It provides a data model, a text file format, and a binary format for (ancient) text plus (linguistic) annotations. The emphasis of this all is on: data processing; sharing data; and contributing modules. A defining characteristic is that

  8. PIGMI mechanical fabrication

    International Nuclear Information System (INIS)

    Hart, V.E.

    1976-01-01

    A prime goal of the mechanical design effort associated with the PIGMI (Pion Generator for Medical Irradiations) program is to investigate new materials and fabrication techniques in an effort to obtain increased machine efficiency and reliability at a reasonable cost. The following discussion deals with the modeling program that LASL is pursuing for 450-MHz and 1350-MHz PIGMI development. (author)

  9. Micromechanical Structures Fabrication; FINAL

    International Nuclear Information System (INIS)

    Rajic, S

    2001-01-01

    Work in materials other than silicon for MEMS applications has typically been restricted to metals and metal oxides instead of more ''exotic'' semiconductors. However, group III-V and II-VI semiconductors form a very important and versatile collection of material and electronic parameters available to the MEMS and MOEMS designer. With these materials, not only are the traditional mechanical material variables (thermal conductivity, thermal expansion, Young's modulus, etc.) available, but also chemical constituents can be varied in ternary and quaternary materials. This flexibility can be extremely important for both friction and chemical compatibility issues for MEMS. In addition, the ability to continually vary the bandgap energy can be particularly useful for many electronics and infrared detection applications. However, there are two major obstacles associated with alternate semiconductor material MEMS. The first issue is the actual fabrication of non-silicon micro-devices and the second impediment is communicating with these novel devices. We have implemented an essentially material independent fabrication method that is amenable to most group III-V and II-VI semiconductors. This technique uses a combination of non-traditional direct write precision fabrication processes such as diamond turning, ion milling, laser ablation, etc. This type of deterministic fabrication approach lends itself to an almost trivial assembly process. We also implemented a mechanical, electrical, and optical self-aligning hybridization technique for these alternate-material MEMS substrates

  10. Fabrication activity for nanophotonics

    DEFF Research Database (Denmark)

    Malureanu, Radu; Chung, Il-Sug; Carletti, Luca

    We present the fabrication and characterization of new structures and materials to be used in nanophotonics. The first structure presented is a fractal metallic metasurface designed to be used as a high-sensitivity sensor for 810nm wavelength. A second structure is a high index contrast grating...

  11. Know-How on design of switching regulator

    International Nuclear Information System (INIS)

    1985-08-01

    This book introduces switching regulator from base to application, which deals with fundamentals of switching regulator such as the reason of boom about switching regulator, understanding simple circuit without electric transformer and decision of circuit type with input voltage and output voltage, configuration and characteristic of switching regulator, a concrete design of switching regulator, pulse width control circuit and protection circuit, concrete circuit examples of switching power and the point of switching regulator.

  12. Stateless multicast switching in software defined networks

    OpenAIRE

    Reed, Martin J.; Al-Naday, Mays; Thomos, Nikolaos; Trossen, Dirk; Petropoulos, George; Spirou, Spiros

    2016-01-01

    Multicast data delivery can significantly reduce traffic in operators' networks, but has been limited in deployment due to concerns such as the scalability of state management. This paper shows how multicast can be implemented in contemporary software defined networking (SDN) switches, with less state than existing unicast switching strategies, by utilising a Bloom Filter (BF) based switching technique. Furthermore, the proposed mechanism uses only proactive rule insertion, and thus, is not l...

  13. AN ANALYTICAL STUDY OF SWITCHING TRACTION MOTORS

    Directory of Open Access Journals (Sweden)

    V. M. Bezruchenko

    2010-03-01

    Full Text Available The analytical study of switching of the tractive engines of electric locomotives is conducted. It is found that the obtained curves of change of current of the sections commuted correspond to the theory of average rectilinear switching. By means of the proposed method it is possible on the stage of design of tractive engines to forecast the quality of switching and to correct it timely.

  14. Monitoring Mellanox Infiniband SX6036 switches

    CERN Document Server

    Agapiou, Marinos

    2017-01-01

    The SX6036 switches addressed by my project, are part of a fully non-blocking fat-tree cluster consisting of 72 servers and 6 Mellanox SX6036 Infiniband switches. My project is about retrieving the appropriate metrics from the Infiniband switch cluster, ingesting the data to Collectd and after my data are being transfered to CERN Database, they are being visualized via Grafana Dashboards.

  15. Optical switches based on surface plasmons

    International Nuclear Information System (INIS)

    Chen Cong; Wang Pei; Yuan Guanghui; Wang Xiaolei; Min Changjun; Deng Yan; Lu Yonghua; Ming Hai

    2008-01-01

    Great attention is being paid to surface plasmons (SPs) because of their potential applications in sensors, data storage and bio-photonics. Recently, more and more optical switches based on surface plasmon effects have been demonstrated either by simulation or experimentally. This article describes the principles, advantages and disadvantages of various types of optical switches based on SPs, in particular the all-optical switches. (authors)

  16. A new switched power linac structure

    International Nuclear Information System (INIS)

    Villa, F.

    1989-03-01

    A new pulse power structure has been described that utilizes an easily accessible rectilinear switch. The new structure is more ''forgiving'' (as far as risetime is concerned) than the radial line transformer, and contains fewer switching structures/unit length. The combination of the new structure with the switch proposed seems to offer interesting possibilities for a future linear collider. 13 refs., 6 figs., 2 tabs

  17. Switching induced oscillations in the logistic map

    Energy Technology Data Exchange (ETDEWEB)

    Maier, Makisha P.S. [Department of Chemistry, Williams College, Williamstown, MA 01267 (United States); Peacock-Lopez, Enrique, E-mail: epeacock@williams.ed [Department of Chemistry, Williams College, Williamstown, MA 01267 (United States)

    2010-02-08

    In ecological modeling, seasonality can be represented as a switching between different environmental conditions. This switching strategy can be related to the so-called Parrondian games, where the alternation of two losing games yield a winning game. Hence we can consider two dynamics that, by themselves, yield undesirable behaviors, but when alternated yield a desirable oscillatory behavior. In this case, we also consider a noisy switching strategy and find that the desirable oscillatory behavior prevails.

  18. Ultrafast pulse generation in photoconductive switches

    DEFF Research Database (Denmark)

    Keil, Ulrich Dieter Felix; Dykaar, D. R.

    1996-01-01

    Carrier and field dynamics in photoconductive switches are investigated by electrooptic sampling and voltage-dependent reflectivity measurements. We show that the nonuniform field distribution due to the two-dimensional nature of coplanar photoconductive switches, in combination with the large di...... difference in the mobilities of holes and electrons, determine the pronounced polarity dependence. Our measurements indicate that the pulse generation mechanism is a rapid voltage breakdown across the photoconductive switch and not a local field breakdown...

  19. A magnetically switched kicker for proton extraction

    International Nuclear Information System (INIS)

    Dinkel, J.; Biggs, J.

    1989-03-01

    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

  20. Properties of a GaAs Single Electron Path Switching Node Device Using a Single Quantum Dot for Hexagonal BDD Quantum Circuits

    International Nuclear Information System (INIS)

    Nakamura, Tatsuya; Abe, Yuji; Kasai, Seiya; Hasegawa, Hideki; Hashizume, Tamotsu

    2006-01-01

    A new single electron (SE) binary-decision diagram (BDD) node device having a single quantum dot connected to three nanowire branches through tunnel barriers was fabricated using etched AlGaAs/GaAs nanowires and nanometer-sized Schottky wrap gates (WPGs), and their operation was characterized experimentally, for the hexagonal BDD quantum circuit. Fabricated devices showed clear and steep single electron pass switching by applying only an input voltage signal, which was completely different from switching properties in the previous SE BDD node devices composed of two single electron switches. As the possible switching mechanism, the correlation between the probabilities of tunnelling thorough a single quantum dot in exit branches was discussed

  1. Bipolar resistive switching of single gold-in-Ga2O3 nanowire.

    Science.gov (United States)

    Hsu, Chia-Wei; Chou, Li-Jen

    2012-08-08

    We have fabricated single nanowire chips on gold-in-Ga(2)O(3) core-shell nanowires using the electron-beam lithography techniques and realized bipolar resistive switching characteristics having invariable set and reset voltages. We attribute the unique property of invariance to the built-in conduction path of gold core. This invariance allows us to fabricate many resistive switching cells with the same operating voltage by simple depositing repetitive metal electrodes along a single nanowire. Other characteristics of these core-shell resistive switching nanowires include comparable driving electric field with other thin film and nanowire devices and a remarkable on/off ratio more than 3 orders of magnitude at a low driving voltage of 2 V. A smaller but still impressive on/off ratio of 10 can be obtained at an even lower bias of 0.2 V. These characteristics of gold-in-Ga(2)O(3) core-shell nanowires make fabrication of future high-density resistive memory devices possible.

  2. Atomic battery with beam switching

    International Nuclear Information System (INIS)

    Edling, E.A.; McKenna, R.P.; Peterick, E.Th. Jr.; Trexler, F.D.

    1984-01-01

    An electric power generating apparatus that is powered primarily by the emission of electrically charged particles from radio-active materials enclosed in an evacuated vessel of glass or the like. An arrangement of reflecting electrodes causes a beam of particles to switch back and forth at a high frequency between two collecting electrodes that are connected to a resonating tuned primary circuit consisting of an inductor with resonating capacitor. The reflecting electrodes are energized in the proper phase relationship to the collecting electrodes to insure sustained oscillation by means of a secondary winding coupled inductively to the primary winding and connected to the reflecting electrodes. Power may be drawn from the circuit at a stepped down voltage from a power take-off winding that is coupled to the primary winding. The disclosure also describes a collecting electrode arrangement consisting of multiple spatially separated electrodes which together serve to capture a maximum of the available particle energy. A self-starting arrangement for start of oscillations is described. A specially adapted version of the invention utilizes two complementary beams of oppositely charged particles which are switched alternatingly between the collecting electrodes

  3. Atomic crystals resistive switching memory

    International Nuclear Information System (INIS)

    Liu Chunsen; Zhang David Wei; Zhou Peng

    2017-01-01

    Facing the growing data storage and computing demands, a high accessing speed memory with low power and non-volatile character is urgently needed. Resistive access random memory with 4F 2 cell size, switching in sub-nanosecond, cycling endurances of over 10 12 cycles, and information retention exceeding 10 years, is considered as promising next-generation non-volatile memory. However, the energy per bit is still too high to compete against static random access memory and dynamic random access memory. The sneak leakage path and metal film sheet resistance issues hinder the further scaling down. The variation of resistance between different devices and even various cycles in the same device, hold resistive access random memory back from commercialization. The emerging of atomic crystals, possessing fine interface without dangling bonds in low dimension, can provide atomic level solutions for the obsessional issues. Moreover, the unique properties of atomic crystals also enable new type resistive switching memories, which provide a brand-new direction for the resistive access random memory. (topical reviews)

  4. Heat switch technology for cryogenic thermal management

    Science.gov (United States)

    Shu, Q. S.; Demko, J. A.; E Fesmire, J.

    2017-12-01

    Systematic review is given of development of novel heat switches at cryogenic temperatures that alternatively provide high thermal connection or ideal thermal isolation to the cold mass. These cryogenic heat switches are widely applied in a variety of unique superconducting systems and critical space applications. The following types of heat switch devices are discussed: 1) magnetic levitation suspension, 2) shape memory alloys, 3) differential thermal expansion, 4) helium or hydrogen gap-gap, 5) superconducting, 6) piezoelectric, 7) cryogenic diode, 8) magneto-resistive, and 9) mechanical demountable connections. Advantages and limitations of different cryogenic heat switches are examined along with the outlook for future thermal management solutions in materials and cryogenic designs.

  5. Stochastic multistep polarization switching in ferroelectrics

    Science.gov (United States)

    Genenko, Y. A.; Khachaturyan, R.; Schultheiß, J.; Ossipov, A.; Daniels, J. E.; Koruza, J.

    2018-04-01

    Consecutive stochastic 90° polarization switching events, clearly resolved in recent experiments, are described by a nucleation and growth multistep model. It extends the classical Kolmogorov-Avrami-Ishibashi approach and includes possible consecutive 90°- and parallel 180° switching events. The model predicts the results of simultaneous time-resolved macroscopic measurements of polarization and strain, performed on a tetragonal Pb (Zr ,Ti ) O3 ceramic in a wide range of electric fields over a time domain of seven orders of magnitude. It allows the determination of the fractions of individual switching processes, their characteristic switching times, activation fields, and respective Avrami indices.

  6. The increased importance of sector switching

    DEFF Research Database (Denmark)

    Frederiksen, Anders; Hansen, Jesper Rosenberg

    2017-01-01

    Sector switching is an important phenomenon that casts light on public–private differences. Yet our knowledge about its prevalence and trends is limited. We study sector switching using unique Danish register-based employer–employee data covering more than 25 years. We find that sector switching...... constitutes 18.5% of all job-to-job mobility, and the trend is increasing both from public to private and from private to public. Sector switching is also generally increasing for middle managers, but for administrative professionals only the flows from private to public increase and for top managers only...... the flows from public to private increase....

  7. Wireless Nanoionic-Based Radio Frequency Switch

    Science.gov (United States)

    Nessel, James A. (Inventor); Miranda, Felix A (Inventor)

    2017-01-01

    A nanoionic switch connected to one or more rectenna modules is disclosed. The rectenna module is configured to receive a wireless signal and apply a first bias to change a state of the nanoionic switch from a first state to a second state. The rectenna module can receive a second wireless signal and apply a second bias to change the nanoionic switch from the second state back to the first state. The first bias is generally opposite of the first bias. The rectenna module accordingly permits operation of the nanoionic switch without onboard power.

  8. Low-Voltage Switched-Capacitor Circuits

    DEFF Research Database (Denmark)

    Bidari, E.; Keskin, M.; Maloberti, F.

    1999-01-01

    Switched-capacitor stages are described which can function with very low (typically 1 V) supply voltages, without using voltage boosting or switched op-amps. Simulations indicate that high performance may be achieved using these circuits in filter or data converter applications.......Switched-capacitor stages are described which can function with very low (typically 1 V) supply voltages, without using voltage boosting or switched op-amps. Simulations indicate that high performance may be achieved using these circuits in filter or data converter applications....

  9. Clocking Scheme for Switched-Capacitor Circuits

    DEFF Research Database (Denmark)

    Steensgaard-Madsen, Jesper

    1998-01-01

    A novel clocking scheme for switched-capacitor (SC) circuits is presented. It can enhance the understanding of SC circuits and the errors caused by MOSFET (MOS) switches. Charge errors, and techniques to make SC circuits less sensitive to them are discussed.......A novel clocking scheme for switched-capacitor (SC) circuits is presented. It can enhance the understanding of SC circuits and the errors caused by MOSFET (MOS) switches. Charge errors, and techniques to make SC circuits less sensitive to them are discussed....

  10. Simplified design of switching power supplies

    CERN Document Server

    Lenk, John

    1995-01-01

    * Describes the operation of each circuit in detail * Examines a wide selection of external components that modify the IC package characteristics * Provides hands-on, essential information for designing a switching power supply Simplified Design of Switching Power Supplies is an all-inclusive, one-stop guide to switching power-supply design. Step-by-step instructions and diagrams render this book essential for the student and the experimenter, as well as the design professional. Simplified Design of Switching Power Supplies concentrates on the use of IC regulators. All popular forms of swit

  11. Demonstration of Ultra-Fast Switching in Nano metallic Resistive Switching Memory Devices

    International Nuclear Information System (INIS)

    Yang, Y.

    2016-01-01

    Interdependency of switching voltage and time creates a dilemma/obstacle for most resistive switching memories, which indicates low switching voltage and ultra-fast switching time cannot be simultaneously achieved. In this paper, an ultra-fast (sub-100 ns) yet low switching voltage resistive switching memory device (“nano metallic ReRAM”) was demonstrated. Experimental switching voltage is found independent of pulse width (intrinsic device property) when the pulse is long but shows abrupt time dependence (“cliff”) as pulse width approaches characteristic RC time of memory device (extrinsic device property). Both experiment and simulation show that the onset of cliff behavior is dependent on physical device size and parasitic resistance, which is expected to diminish as technology nodes shrink down. We believe this study provides solid evidence that nano metallic resistive switching memory can be reliably operated at low voltage and ultra-fast regime, thus beneficial to future memory technology.

  12. Status report, canister fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Claes-Goeran; Eriksson, Peter; Westman, Marika [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Emilsson, Goeran [CSM Materialteknik AB, Linkoeping (Sweden)

    2004-06-01

    The report gives an account of the development of material and fabrication technology for copper canisters with cast inserts during the period from 2000 until the start of 2004. The engineering design of the canister and the choice of materials in the constituent components described in previous status reports have not been significantly changed. In the reference canister, the thickness of the copper shell is 50 mm. Fabrication of individual components with a thinner copper thickness is done for the purpose of gaining experience and evaluating fabrication and inspection methods for such canisters. As a part of the development of cast inserts, computer simulations of the casting processes and techniques used at the foundries have been performed for the purpose of optimizing the material properties. These properties have been evaluated by extensive tensile testing and metallographic inspection of test material taken from discs cut at different points along the length of the inserts. The testing results exhibit a relatively large spread. Low elongation values in certain tensile test specimens are due to the presence of poorly formed graphite, porosities, slag or other casting defects. It is concluded in the report that it will not be possible to avoid some presence of observed defects in castings of this size. In the deep repository, the inserts will be exposed to compressive loading and the observed defects are not critical for strength. An analysis of the strength of the inserts and formulation of relevant material requirements must be based on a statistical approach with probabilistic calculations. This work has been initiated and will be concluded during 2004. An initial verifying compression test of a canister in an isostatic press has indicated considerable overstrength in the structure. Seamless copper tubes are fabricated by means of three methods: extrusion, pierce and draw processing, and forging. It can be concluded that extrusion tests have revealed a

  13. Status report, canister fabrication

    International Nuclear Information System (INIS)

    Andersson, Claes-Goeran; Eriksson, Peter; Westman, Marika; Emilsson, Goeran

    2004-06-01

    The report gives an account of the development of material and fabrication technology for copper canisters with cast inserts during the period from 2000 until the start of 2004. The engineering design of the canister and the choice of materials in the constituent components described in previous status reports have not been significantly changed. In the reference canister, the thickness of the copper shell is 50 mm. Fabrication of individual components with a thinner copper thickness is done for the purpose of gaining experience and evaluating fabrication and inspection methods for such canisters. As a part of the development of cast inserts, computer simulations of the casting processes and techniques used at the foundries have been performed for the purpose of optimizing the material properties. These properties have been evaluated by extensive tensile testing and metallographic inspection of test material taken from discs cut at different points along the length of the inserts. The testing results exhibit a relatively large spread. Low elongation values in certain tensile test specimens are due to the presence of poorly formed graphite, porosities, slag or other casting defects. It is concluded in the report that it will not be possible to avoid some presence of observed defects in castings of this size. In the deep repository, the inserts will be exposed to compressive loading and the observed defects are not critical for strength. An analysis of the strength of the inserts and formulation of relevant material requirements must be based on a statistical approach with probabilistic calculations. This work has been initiated and will be concluded during 2004. An initial verifying compression test of a canister in an isostatic press has indicated considerable overstrength in the structure. Seamless copper tubes are fabricated by means of three methods: extrusion, pierce and draw processing, and forging. It can be concluded that extrusion tests have revealed a

  14. A study on the resistance switching of Ag2Se and Ta2O5 heterojunctions using structural engineering

    Science.gov (United States)

    Lee, Tae Sung; Lee, Nam Joo; Abbas, Haider; Hu, Quanli; Yoon, Tae-Sik; Lee, Hyun Ho; Le Shim, Ee; Kang, Chi Jung

    2018-01-01

    The resistive random access memory (RRAM) devices with heterostuctures have been investigated due to cycling stability, nonlinear switching, complementary resistive switching and self-compliance. The heterostructured devices can modulate the resistive switching (RS) behavior appropriately by bilayer structure with a variety of materials. In this study, the bipolar resistive switching characteristics of the bilayer structures composed of Ta2O5 and Ag2Se, which are transition-metal oxide (TMO) and silver chalcogenide, were investigated. The bilayer devices of Ta2O5 deposited on Ag2Se (Ta2O5/Ag2Se) and Ag2Se deposited on Ta2O5 (Ag2Se/Ta2O5) were fabricated for investigation of the RS characteristics by stacking sequence of Ta2O5 and Ag2Se. All operating voltages were applied to the Ag top electrode with the Pt bottom electrode grounded. The Ta2O5/Ag2Se device showed that a negative voltage sweep switched the device from high resistance state (HRS) to low resistance state (LRS) and a positive voltage sweep switched the device from LRS to HRS. On the contrary, for the Ag2Se/Ta2O5 device a positive voltage sweep switched the device from HRS to LRS, and a negative voltage sweep switched it from LRS to HRS. The polarity dependence of RS was attributed to the stacking sequence of Ta2O5 and Ag2Se. In addition, the combined heterostructured device of both bilayer stacks, Ta2O5/Ag2Se and Ag2Se/Ta2O5, exhibited the complementary switching characteristics. By using threshold switching devices, sneak path leakage can be reduced without additional selectors. The bilayer heterostructures of Ta2O5 and Ag2Se have various advantages such as self-compliance, reproducibility and forming-free stable RS. It confirms the possible applications of TMO and silver chalcogenide heterostructures in RRAM.

  15. The Application of High Temperature Superconducting Materials to Power Switches

    CERN Document Server

    March, S A; Ballarino, A

    2009-01-01

    Superconducting switches may find application in superconducting magnet systems that require energy extraction. Such superconducting switches could be bypass-switches that are operated in conjunction with a parallel resistor or dump-switches where all of the energy is dissipated in the switch itself. Bypass-switches are more suited to higher energy circuits as a portion of the energy can be dissipated in the external dump resistor. Dump- switches require less material and triggering energy as a lower switch resistance is needed to achieve the required total dump resistance. Both superconducting bypass-switches and superconducting dump-switches can be ther- mally activated. Switching times that are comparable to those obtained with mechanical bypass-switch systems can be achieved using a co-wound heater that is powered by a ca- pacitor discharge. Switches that have fast thermal diffusion times through the insulation can be modelled as a lumped system whereas those with slow thermal diffusion times were modelle...

  16. Optimal control of switching time in switched stochastic systems with multi-switching times and different costs

    Science.gov (United States)

    Liu, Xiaomei; Li, Shengtao; Zhang, Kanjian

    2017-08-01

    In this paper, we solve an optimal control problem for a class of time-invariant switched stochastic systems with multi-switching times, where the objective is to minimise a cost functional with different costs defined on the states. In particular, we focus on problems in which a pre-specified sequence of active subsystems is given and the switching times are the only control variables. Based on the calculus of variation, we derive the gradient of the cost functional with respect to the switching times on an especially simple form, which can be directly used in gradient descent algorithms to locate the optimal switching instants. Finally, a numerical example is given, highlighting the validity of the proposed methodology.

  17. Thickness effect of ultra-thin Ta2O5 resistance switching layer in 28 nm-diameter memory cell

    Science.gov (United States)

    Park, Tae Hyung; Song, Seul Ji; Kim, Hae Jin; Kim, Soo Gil; Chung, Suock; Kim, Beom Yong; Lee, Kee Jeung; Kim, Kyung Min; Choi, Byung Joon; Hwang, Cheol Seong

    2015-11-01

    Resistance switching (RS) devices with ultra-thin Ta2O5 switching layer (0.5-2.0 nm) with a cell diameter of 28 nm were fabricated. The performance of the devices was tested by voltage-driven current—voltage (I-V) sweep and closed-loop pulse switching (CLPS) tests. A Ta layer was placed beneath the Ta2O5 switching layer to act as an oxygen vacancy reservoir. The device with the smallest Ta2O5 thickness (0.5 nm) showed normal switching properties with gradual change in resistance in I-V sweep or CLPS and high reliability. By contrast, other devices with higher Ta2O5 thickness (1.0-2.0 nm) showed abrupt switching with several abnormal behaviours, degraded resistance distribution, especially in high resistance state, and much lower reliability performance. A single conical or hour-glass shaped double conical conducting filament shape was conceived to explain these behavioural differences that depended on the Ta2O5 switching layer thickness. Loss of oxygen via lateral diffusion to the encapsulating Si3N4/SiO2 layer was suggested as the main degradation mechanism for reliability, and a method to improve reliability was also proposed.

  18. Sequential Effects in Deduction: Cost of Inference Switch

    Science.gov (United States)

    Milan, Emilio G.; Moreno-Rios, Sergio; Espino, Orlando; Santamaria, Carlos; Gonzalez-Hernandez, Antonio

    2010-01-01

    The task-switch paradigm has helped psychologists gain insight into the processes involved in changing from one activity to another. The literature has yielded consistent results about switch cost reconfiguration (abrupt offset in regular task-switch vs. gradual reduction in random task-switch; endogenous and exogenous components of switch cost;…

  19. Automated breeder fuel fabrication

    International Nuclear Information System (INIS)

    Goldmann, L.H.; Frederickson, J.R.

    1983-01-01

    The objective of the Secure Automated Fabrication (SAF) Project is to develop remotely operated equipment for the processing and manufacturing of breeder reactor fuel pins. The SAF line will be installed in the Fuels and Materials Examination Facility (FMEF). The FMEF is presently under construction at the Department of Energy's (DOE) Hanford site near Richland, Washington, and is operated by the Westinghouse Hanford Company (WHC). The fabrication and support systems of the SAF line are designed for computer-controlled operation from a centralized control room. Remote and automated fuel fabriction operations will result in: reduced radiation exposure to workers; enhanced safeguards; improved product quality; near real-time accountability, and increased productivity. The present schedule calls for installation of SAF line equipment in the FMEF beginning in 1984, with qualifying runs starting in 1986 and production commencing in 1987. 5 figures

  20. OPO fabric decontamination

    International Nuclear Information System (INIS)

    Severa, J.; Bar, J.; Grujbar, V.

    1978-01-01

    Samples of five polypropylene-based man-made fabrics were studied with regard to the degree of contamination and possibilities of decontamination in order to assess their suitability as material for protective clothing in the nuclear industry. The contamination degree of the fabrics in an aqueous solution of a fission product mixture was found to be low. Soaking in a mixture of the Sapon detergent and sodium hexametaphosphate at a concentration of both materials of 1 g/l with subsequent washing in a solution of the Zenit detergent at a concentration of 3 g/l was suggested as the most suitable decontamination procedure. It reduces the initial contamination by almost 99%. (Z.M.)

  1. Magnetization states and switching in narrow-gapped ferromagnetic nanorings

    Directory of Open Access Journals (Sweden)

    Jie Li

    2012-03-01

    Full Text Available We study permalloy nanorings that are lithographically fabricated with narrow gaps that break the rotational symmetry of the ring while retaining the vortex ground state, using both micromagnetic simulations and magnetic force microscopy (MFM. The vortex chirality in these structures can be readily set with an in-plane magnetic field and easily probed by MFM due to the field associated with the gap, suggesting such rings for possible applications in storage technologies. We find that the gapped ring edge characteristics (i.e., edge profile and gap shape are critical in determining the magnetization switching field, thus elucidating an essential parameter in the controls of devices that might incorporate such structures.

  2. Strain controlled switching effects in phosphorene and GeS.

    Science.gov (United States)

    Li, B W; Wang, Y; Xie, Y Q; Zhu, L; Yao, K L

    2017-10-27

    By performing first principles calculations within the combined approach of density functional theory and nonequilibrium Green's function technique, we have designed some nanoelectronic devices to explore the ferroelastic switching of phosphorene and phosphorene analogs GeS. With the structure swapping along the zigzag direction and armchair direction, band gap transformed at different states due to their anisotropic phosphorene-like structure. From the initial state to the middle state, the band gap becomes progressively smaller, after that, it becomes wide. By analyzing transmission coefficients, it is found that the transport properties of phosphorene and GeS can be controlled by a uniaxial strain. The results also manifest that GeS has great potential to fabricate ferroic nonvolatile memory devices, because its relatively high on/off transmission coefficient ratio (∼1000) between the two stable ferroelastic states.

  3. Simulation and optimization of a polymer directional coupler electro-optic switch with push pull electrodes

    Science.gov (United States)

    Zheng, Chuan-Tao; Ma, Chun-Sheng; Yan, Xin; Wang, Xian-Yin; Zhang, Da-Ming

    2008-07-01

    Structural model and design technique are proposed for a polymer directional coupler electro-optic switch with rib waveguides and push-pull electrodes, of which the electric field distribution is analyzed by the conformal transforming method and image method. In order to get the minimum mode loss and the minimum switching voltage, the parameters of the waveguide and electrode are optimized, such as the core with, core thickness, buffer layer between the core and the electrode, coupling gap between the waveguides, electrode thickness, electrode width and electrode gap. Switching Characteristics are analyzed, which include the output power, insertion loss, and crosstalk. To realize normal switching function, the fabrication error, spectrum shift, and coupling loss between a single mode fiber (SMF) and the waveguide are discussed. Simulation results show that the coupling length is 3082 μm, push-pull switching voltage is 2.14 V, insertion loss is less than 1.17 dB, and crosstalk is less than -30 dB for the designed device.

  4. Superconducting Switch for Fast On-Chip Routing of Quantum Microwave Fields

    Science.gov (United States)

    Pechal, M.; Besse, J.-C.; Mondal, M.; Oppliger, M.; Gasparinetti, S.; Wallraff, A.

    2016-08-01

    A switch capable of routing microwave signals at cryogenic temperatures is a desirable component for state-of-the-art experiments in many fields of applied physics, including but not limited to quantum-information processing, communication, and basic research in engineered quantum systems. Conventional mechanical switches provide low insertion loss but disturb operation of dilution cryostats and the associated experiments by heat dissipation. Switches based on semiconductors or microelectromechanical systems have a lower thermal budget but are not readily integrated with current superconducting circuits. Here we design and test an on-chip switch built by combining tunable transmission-line resonators with microwave beam splitters. The device is superconducting and as such dissipates a negligible amount of heat. It is compatible with current superconducting circuit fabrication techniques, operates with a bandwidth exceeding 100 MHz, is capable of handling photon fluxes on the order of 1 05 μ s-1 , equivalent to powers exceeding -90 dBm , and can be switched within approximately 6-8 ns. We successfully demonstrate operation of the device in the quantum regime by integrating it on a chip with a single-photon source and using it to route nonclassical itinerant microwave fields at the single-photon level.

  5. Electric field-triggered metal-insulator transition resistive switching of bilayered multiphasic VOx

    Science.gov (United States)

    Won, Seokjae; Lee, Sang Yeon; Hwang, Jungyeon; Park, Jucheol; Seo, Hyungtak

    2018-01-01

    Electric field-triggered Mott transition of VO2 for next-generation memory devices with sharp and fast resistance-switching response is considered to be ideal but the formation of single-phase VO2 by common deposition techniques is very challenging. Here, VOx films with a VO2-dominant phase for a Mott transition-based metal-insulator transition (MIT) switching device were successfully fabricated by the combined process of RF magnetron sputtering of V metal and subsequent O2 annealing to form. By performing various material characterizations, including scanning transmission electron microscopy-electron energy loss spectroscopy, the film is determined to have a bilayer structure consisting of a VO2-rich bottom layer acting as the Mott transition switching layer and a V2O5/V2O3 mixed top layer acting as a control layer that suppresses any stray leakage current and improves cyclic performance. This bilayer structure enables excellent electric field-triggered Mott transition-based resistive switching of Pt-VOx-Pt metal-insulator-metal devices with a set/reset current ratio reaching 200, set/reset voltage of less than 2.5 V, and very stable DC cyclic switching upto 120 cycles with a great set/reset current and voltage distribution less than 5% of standard deviation at room temperature, which are specifications applicable for neuromorphic or memory device applications. [Figure not available: see fulltext.

  6. Raman analysis of ferroelectric switching in niobium-doped lead zirconate titanate thin films

    International Nuclear Information System (INIS)

    Ferrari, P.; Ramos-Moore, E.; Guitar, M.A.; Cabrera, A.L.

    2014-01-01

    Characteristic Raman vibration modes of niobium-doped lead zirconate titanate (PNZT) are studied as a function of ferroelectric domain switching. The microstructure of PNZT is characterized by scanning electron microscopy and X-ray diffraction. Ferroelectric switching is achieved by applying voltages between the top (Au) and bottom (Pt) electrodes, while acquiring the Raman spectra in situ. Vibrational active modes associated with paraelectric and ferroelectric phases are identified after measuring above and below the ferroelectric Curie temperature, respectively. Changes in the relative intensities of the Raman peaks are observed as a function of the switching voltage. The peak area associated with the ferroelectric modes is analyzed as a function of the applied voltage within one ferroelectric polarization loop, showing local maxima around the coercive voltage. This behavior can be understood in terms of the correlation between vibrational and structural properties, since ferroelectric switching modifies the interaction between the body-centered atom (Zr, Ti or Nb) and the Pb–O lattice. - Highlights: • Electric fields induce structural distortions on ferroelectric perovskites. • Ferroelectric capacitor was fabricated to perform hysteresis loops. • Raman analysis was performed in situ during ferroelectric switching. • Raman modes show hysteresis and inflections around the coercive voltages. • Data can be understood in terms of vibrational–structural correlations

  7. Resistive switching properties and physical mechanism of europium oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Wei; Zou, Changwei [School of Physical Science and Technology, Lingnan Normal University, Zhanjiang (China); Bao, Dinghua [State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou (China)

    2017-09-15

    A forming-free resistive switching effect was obtained in Pt/Eu{sub 2}O{sub 3}/Pt devices in which the Eu{sub 2}O{sub 3} thin films were fabricated by a chemical solution deposition method. The devices show unipolar resistive switching with excellent switching parameters, such as high resistance ratio (10{sup 7}), stable resistance values (read at 0.2 V), low reset voltage, good endurance, and long retention time (up to 10{sup 4} s). On the basis of the analysis of the current-voltage (I-V) curves and the resistance-temperature dependence, it can be concluded that the dominant conducting mechanisms were ohmic behavior and Schottky emission at low resistance state and high resistance state, respectively. The resistive switching behavior could be explained by the formation and rupture of conductive filament, which is related to the abundant oxygen vacancies generated in the deposition process. This work demonstrates the great potential opportunities of Eu{sub 2}O{sub 3} thin film in resistive switching memory applications, which might possess distinguished properties. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Intentionally fabricated autobiographical memories

    OpenAIRE

    Justice, LV; Morrison, CM; Conway, MA

    2017-01-01

    Participants generated both autobiographical memories (AMs) that they believed to be true and intentionally fabricated autobiographical memories (IFAMs). Memories were constructed while a concurrent memory load (random 8-digit sequence) was held in mind or while there was no concurrent load. Amount and accuracy of recall of the concurrent memory load was reliably poorer following generation of IFAMs than following generation of AMs. There was no reliable effect of load on memory generation ti...

  9. Colored fused filament fabrication

    OpenAIRE

    Song, Haichuan; Lefebvre, Sylvain

    2017-01-01

    Filament fused fabrication is the method of choice for printing 3D models at low cost, and is the de-facto standard for hobbyists, makers and schools. Unfortunately, filament printers cannot truly reproduce colored objects. The best current techniques rely on a form of dithering exploiting occlusion, that was only demonstrated for shades of two base colors and that behaves differently depending on surface slope. We explore a novel approach for 3D printing colored objects, capable of creating ...

  10. Advanced fuel fabrication

    International Nuclear Information System (INIS)

    Bernard, H.

    1989-01-01

    This paper deals with the fabrication of advanced fuels, such as mixed oxides for Pressurized Water Reactors or mixed nitrides for Fast Breeder Reactors. Although an extensive production experience exists for the mixed oxides used in the FBR, important work is still needed to improve the theoretical and technical knowledge of the production route which will be introduced in the future European facility, named Melox, at Marcoule. Recently, the feasibility of nitride fuel fabrication in existing commercial oxide facilities was demonstrated in France. The process, based on carbothermic reduction of oxides with subsequent comminution of the reaction product, cold pressing and sintering provides (U, Pu)N pellets with characteristics suitable for irradiation testing. Two experiments named NIMPHE 1 and 2 fabricated in collaboration with ITU, Karlsruhe, involve 16 nitride and 2 carbide pins, operating at a linear power of 45 and 73 kW/m with a smear density of 75-80% TD and a high burn-up target of 15 at%. These experiments are currently being irradiated in Phenix, at Marcoule. (orig.)

  11. Rotation Impact of Reed Switch

    International Nuclear Information System (INIS)

    Park, Yun Bum; Lee, Jae Seon; Kim, Jong Wook; Han, Eun Sil; Park, Hee June

    2016-01-01

    A CRDM (Control Rod Drive Mechanism) is an electromagnetic device which drives a control rod assembly linearly to regulate the reactivity of a nuclear core. A RPIS (Rod Position Indication System) is used as a position indicator of a control rod assembly for a CRDM of a nuclear reactor, SMART. A highly accurate RPIS for SMART is required because the reactivity of a nuclear core for a small modular reactor is more sensitive than the commercial ones. In this study, the effect of positioning direction of the reeds in a reed switch for the CRDM RPIS has been studied using the electromagnetic FE analysis. It is found that the positioning direction of the reeds slightly but not significantly affects the formation of attraction. Analysis results will be used as the basis on estimated accuracy of full RPIS system.

  12. Rotation Impact of Reed Switch

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yun Bum; Lee, Jae Seon; Kim, Jong Wook [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Han, Eun Sil [Taesung S and E, Seoul (Korea, Republic of); Park, Hee June [Woojin Inc., Hwaseong (Korea, Republic of)

    2016-10-15

    A CRDM (Control Rod Drive Mechanism) is an electromagnetic device which drives a control rod assembly linearly to regulate the reactivity of a nuclear core. A RPIS (Rod Position Indication System) is used as a position indicator of a control rod assembly for a CRDM of a nuclear reactor, SMART. A highly accurate RPIS for SMART is required because the reactivity of a nuclear core for a small modular reactor is more sensitive than the commercial ones. In this study, the effect of positioning direction of the reeds in a reed switch for the CRDM RPIS has been studied using the electromagnetic FE analysis. It is found that the positioning direction of the reeds slightly but not significantly affects the formation of attraction. Analysis results will be used as the basis on estimated accuracy of full RPIS system.

  13. Electro-optical switching of liquid crystals of graphene oxide

    Science.gov (United States)

    Song, Jang-Kun

    Electric field effects on aqueous graphene-oxide (GO) dispersions are reviewed in this chapter. In isotropic and biphasic regimes of GO dispersions, in which the inter-particle friction is low, GO particles sensitively respond to the application of electric field, producing field-induced optical birefringence. The electro-optical sensitivity dramatically decreases as the phase transits to the nematic phase; the increasing inter-particle friction hinders the rotational switching of GO particles. The corresponding Kerr coefficient reaches the maximum near the isotropic to biphasic transition concentration, at which the Kerr coefficient is found be c.a. 1:8 · 10-5 mV-2, the highest value ever reported in all Kerr materials. The exceptionally large Kerr effect arises from the Maxwell- Wagner polarization of GO particles with an extremely large aspect ratio and a thick electrical double layer (EDL). The polarization sensitively depends on the ratio of surface and bulk conductivities in dispersions. As a result, low ion concentration in bulk solvent is highly required to achieve a quality electro-optical switching in GO dispersions. Spontaneous vinylogous carboxylic reaction in GO particles produces H+ ions, resulting in spontaneous degradation of electro-optical response with time, hence the removal of residual ions by using a centrifuge cleaning process significantly improves the electro-optical sensitivity. GO particle size is another important parameter for the Kerr coefficient and the response time. The best performance is observed in a GO dispersion with c.a. 0.5 μm mean size. Dielectrophoretic migration of GO particles can be also used to manipulate GO particles in solution. Using these unique features of GO dispersions, one can fabricate GO liquid crystal devices similar to conventional liquid crystal displays; the large Kerr effect allows fabricating a low power device working at extremely low electric fields.

  14. Chiroptical Molecular Switches 1; Principles and Syntheses.

    NARCIS (Netherlands)

    Lange, Ben de; Jager, Wolter F.; Feringa, Bernard

    1992-01-01

    The concept and the synthesis of the basic molecules for a chiroptical molecular switch are described. This molecular switch is based on photochemical interconversion of two bistable forms of chiral sterically overcrowded olefins. A large variety of these alkenes with different properties have been

  15. Novel RF-MEMS capacitive switching structures

    NARCIS (Netherlands)

    Rottenberg, X.; Jansen, Henricus V.; Fiorini, P.; De Raedt, W.; Tilmans, H.A.C.

    2002-01-01

    This paper reports on novel RF-MEMS capacitive switching devices implementing an electrically floating metal layer covering the dielectric to ensure intimate contact with the bridge in the down state. This results in an optimal switch down capacitance and allows optimisation of the down/up

  16. High-explosive driven crowbar switch

    International Nuclear Information System (INIS)

    Dike, R.S.; Kewish, R.W. Jr.

    1976-01-01

    The disclosure relates to a compact explosive driven switch for use as a low resistance, low inductance crowbar switch. A high-explosive charge extrudes a deformable conductive metallic plate through a polyethylene insulating layer to achieve a hard current contact with a supportive annular conductor

  17. Simulation of linear Switched Reluctance Motor drives

    OpenAIRE

    Garcia Amoros, Jordi; Blanqué Molina, Balduino; Andrada Gascón, Pedro

    2011-01-01

    This paper presents a simulation model of linear switched reluctance motor drives. A Matlab-Simulink environment coupled with finite element analysis is used to perform the simulations. Experimental and simulation results for a double sided linear switched motor drive prototype are reported and compared to verify the simulation model.

  18. Photonic crystal Fano lasers and Fano switches

    DEFF Research Database (Denmark)

    Mørk, Jesper; Yu, Yi; Bekele, Dagmawi Alemayehu

    2017-01-01

    We show that Fano resonances can be realized in photonic crystal membrane structures by coupling line-defect waveguides and point-defect nanocavities. The Fano resonance can be exploited to realize optical switches with very small switching energy, as well as Fano lasers, that can generate short...

  19. Tutorial: Integrated-photonic switching structures

    Science.gov (United States)

    Soref, Richard

    2018-02-01

    Recent developments in waveguided 2 × 2 and N × M photonic switches are reviewed, including both broadband and narrowband resonant devices for the Si, InP, and AlN platforms. Practical actuation of switches by electro-optical and thermo-optical techniques is discussed. Present datacom-and-computing applications are reviewed, and potential applications are proposed for chip-scale photonic and optoelectronic integrated switching networks. Potential is found in the reconfigurable, programmable "mesh" switches that enable a promising group of applications in new areas beyond those in data centers and cloud servers. Many important matrix switches use gated semiconductor optical amplifiers. The family of broadband, directional-coupler 2 × 2 switches featuring two or three side-coupled waveguides deserves future experimentation, including devices that employ phase-change materials. The newer 2 × 2 resonant switches include standing-wave resonators, different from the micro-ring traveling-wave resonators. The resonant devices comprise nanobeam interferometers, complex-Bragg interferometers, and asymmetric contra-directional couplers. Although the fast, resonant devices offer ultralow switching energy, ˜1 fJ/bit, they have limitations. They require several trade-offs when deployed, but they do have practical application.

  20. Proceedings of the switched power workshop

    International Nuclear Information System (INIS)

    Fernow, R.C.

    1988-01-01

    These proceedings contain most of the presentations given at a workshop on the current state of research in techniques for switched power acceleration. The proceedings are divided, as was the workshop itself, into two parts. Part 1, contains the latest results from a number of groups active in switched power research. The major topic here is a method for switching externally supplied power onto a transmission line. Advocates for vacuum photodiode switching, solid state switching, gas switching, and synthetic pulse generation are all presented. Other important areas of research described in this section concern: external electrical and laser pulsing systems; the properties of the created electromagnetic pulse; structures used for transporting the electromagnetic pulse to the region where the electron beam is located; and possible applications. Part 2 of the proceedings considers the problem of designing a high brightness electron gun using switched power as the power source. This is an important first step in demonstrating the usefulness of switched power techniques for accelerator physics. In addition such a gun could have immediate practical importance for advanced acceleration studies since the brightness could exceed that of present sources by several orders of magnitude. I would like to take this opportunity to thank Kathleen Tuohy and Patricia Tuttle for their assistance in organizing and running the workshop. Their tireless efforts contribute greatly to a very productive meeting

  1. Unity power factor switching regulator

    Science.gov (United States)

    Rippel, Wally E. (Inventor)

    1983-01-01

    A single or multiphase boost chopper regulator operating with unity power factor, for use such as to charge a battery is comprised of a power section for converting single or multiphase line energy into recharge energy including a rectifier (10), one inductor (L.sub.1) and one chopper (Q.sub.1) for each chopper phase for presenting a load (battery) with a current output, and duty cycle control means (16) for each chopper to control the average inductor current over each period of the chopper, and a sensing and control section including means (20) for sensing at least one load parameter, means (22) for producing a current command signal as a function of said parameter, means (26) for producing a feedback signal as a function of said current command signal and the average rectifier voltage output over each period of the chopper, means (28) for sensing current through said inductor, means (18) for comparing said feedback signal with said sensed current to produce, in response to a difference, a control signal applied to the duty cycle control means, whereby the average inductor current is proportionate to the average rectifier voltage output over each period of the chopper, and instantaneous line current is thereby maintained proportionate to the instantaneous line voltage, thus achieving a unity power factor. The boost chopper is comprised of a plurality of converters connected in parallel and operated in staggered phase. For optimal harmonic suppression, the duty cycles of the switching converters are evenly spaced, and by negative coupling between pairs 180.degree. out-of-phase, peak currents through the switches can be reduced while reducing the inductor size and mass.

  2. Switched-capacitor isolated LED driver

    Science.gov (United States)

    Sanders, Seth R.; Kline, Mitchell

    2016-03-22

    A switched-capacitor voltage converter which is particularly well-suited for receiving a line voltage from which to drive current through a series of light emitting diodes (LEDs). Input voltage is rectified in a multi-level rectifier network having switched capacitors in an ascending-bank configuration for passing voltages in uniform steps between zero volts up to full received voltage V.sub.DC. A regulator section, operating on V.sub.DC, comprises switched-capacitor stages of H-bridge switching and flying capacitors. A current controlled oscillator drives the states of the switched-capacitor stages and changes its frequency to maintain a constant current to the load. Embodiments are described for isolating the load from the mains, utilizing an LC tank circuit or a multi-primary-winding transformer.

  3. Seismic switch for strong motion measurement

    Science.gov (United States)

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

    1995-05-30

    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.

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

    Science.gov (United States)

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

    2018-06-01

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

  5. Contraceptive method switching in the United States.

    Science.gov (United States)

    Grady, William R; Billy, John O G; Klepinger, Daniel H

    2002-01-01

    Switching among contraceptive method types is the primary determinant of the prevalence of use of specific contraceptive methods, and it has direct implications for women's ability to avoid unintended pregnancies. Yet, method switching among U.S. women has received little attention from researchers. Data from the 1995 National Survey of Family Growth were used to construct multiple-decrement life tables to explore the gross switching rates of married and unmarried women. Within each group, discrete-time hazard models were estimated to determine how women's characteristics affect their switching behavior. Overall rates of method switching are high among both married and unmarried women (40% and 61%, respectively). Married women's two-year switching rates vary from 30% among women who use the implant, injectable, IUD or other reversible methods to 43% among nonusers, while unmarried women's rates vary from 33% among women who use the implant, injectable or IUD to 70% among nonusers. Multivariate analyses of method switching according to women's characteristics indicate that among married women, women without children are less likely than other women to adopt sterilization or a long-term reversible contraceptive (the implant, injectable or IUD). Older married women have a higher rate than their younger counterparts of switching to sterilization, but are also more likely to continue using no method. Among unmarried women, younger and more highly educated women have high rates of switching to the condom and to dual methods. Women's method switching decisions may be driven primarily by concerns related to level and duration of contraceptive effectiveness, health risks associated with contraceptive use and, among single women, sexually transmitted disease prevention.

  6. Development of the switching components for ZT-40

    International Nuclear Information System (INIS)

    Melton, J.G.; Dike, R.S.; Hanks, K.W.; Nunnally, W.C.

    1977-01-01

    Switching of the main capacitor banks for ZT-40 will be accomplished by spark gap switches. Initially, there will be 576 start switches and 288 crowbar switches. A development program is under way to develop three switches; (1) a versatile start switch, which can be used for both the I/sub z/ and the I/sub theta/ capacitor banks, with a wide operating voltage range, (2) a crowbar switch which is capable of crowbarring the circuit without the power crowbar bank, and (3) a power crowbar switch, which can handle 50 to 100 coulombs, so that a large number of crowbar switches will not be required when the power crowbar circuit is added. The problems with the start switches and the first crowbar switch have been solved, or alleviated. The development of a power crowbar switch has just begun

  7. Fabrication and electrical characterization of ultra-thin substrate IGBT

    OpenAIRE

    Guhathakurta, Jajnabalkya

    2013-01-01

    Current topics such as electro-mobility and renewable energy demand the development of power devices with high voltage and current ratings along with minimum switching losses. Amongst the power devices in today’s market, IGBTs have gained a lot of significance in this field over its competitors like Power MOSFETS and Thyristors. Today’s industry has recently taken a huge step in this direction to implement the use of thin-wafer technology for fabrication of IGBTs to reduce the on-resistance. ...

  8. Fabrication and physical properties of permalloy nano-size wires

    International Nuclear Information System (INIS)

    Yu, C.; Lee, S.F.; Yao, Y.D.; Wong, M.S.; Huang, E.W.; Ma, Y.-R.; Tsai, J.L.; Chang, C.R.

    2003-01-01

    Nano-size NiFe wires with patterned shapes in half-ring-in-series, octagon-in-series, and zigzag-in-series configurations were fabricated. Their magnetoresistance was studied below room temperature and their magnetic domain images were investigated at room temperature by a magnetic force microscope. In general, we have experimentally demonstrated that the variation of the magnetoresistance of our patterned nano-size wires can be related to different domain configurations and explained by the domain switching effect. The number of magnetic domain walls in our patterned wires can be controlled by the shape anisotropy and the size of each section of patterns that form the wires

  9. Oxygen-ion-migration-modulated bipolar resistive switching and complementary resistive switching in tungsten/indium tin oxide/gold memory device

    Science.gov (United States)

    Wu, Xinghui; Zhang, Qiuhui; Cui, Nana; Xu, Weiwei; Wang, Kefu; Jiang, Wei; Xu, Qixing

    2018-06-01

    In this paper, we report our investigation of room-temperature-fabricated tungsten/indium tin oxide/gold (W/ITO/Au) resistive random access memory (RRAM), which exhibits asymmetric bipolar resistive switching (BRS) behavior. The device displays good write/erase endurance and data retention properties. The device shows complementary resistive switching (CRS) characteristics after controlling the compliance current. A WO x layer electrically formed at the W/ITO in the forming process. Mobile oxygen ions within ITO migrate toward the electrode/ITO interface and produce a semiconductor-like layer that acts as a free-carrier barrier. The CRS characteristic here can be elucidated in light of the evolution of an asymmetric free-carrier blocking layer at the electrode/ITO interface.

  10. Asymmetric Superhydrophobic/Superhydrophilic Cotton Fabrics Designed by Spraying Polymer and Nanoparticles.

    Science.gov (United States)

    Sasaki, Kaichi; Tenjimbayashi, Mizuki; Manabe, Kengo; Shiratori, Seimei

    2016-01-13

    Inspired by the special wettability of certain natural life forms, such as the high water repellency of lotus leaves, many researchers have attempted to impart superhydrophobic properties to fabrics in academic and industrial contexts. Recently, a new switching system of wettability has inspired a strong demand for advanced coatings, even though their fabrication remains complex and costly. Here, cotton fabrics with asymmetric wettability (one face with natural superhydrophilicity and one face with superhydrophobicity) were fabricated by one-step spraying of a mixture of biocompatible commercial materials, hydrophobic SiO2 nanoparticles and ethyl-α-cyanoacrylate superglue. Our approach involves controlling the permeation of the fabric coatings by changing the distance between the fabric and the sprayer, to make one side superhydrophobic and the other side naturally superhydrophilic. As a result, the superhydrophobic side, with its high mechanical durability, exhibited a water contact angle of 154° and sliding angle of 16°, which meets the requirement for self-cleaning ability of surfaces. The opposite side exhibited high water absorption ability owing to the natural superhydrophilic property of the fabric. In addition, the designed cotton fabrics had blood absorption and clotting abilities on the superhydrophilic side, while the superhydrophobic side prevented water and blood permeation without losing the natural breathability of the cotton. These functions may be useful in the design of multifunctional fabrics for medical applications.

  11. Intraocular lens fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Salazar, Mike A. (Albuquerque, NM); Foreman, Larry R. (Los Alamos, NM)

    1997-01-01

    This invention describes a method for fabricating an intraocular lens made rom clear Teflon.TM., Mylar.TM., or other thermoplastic material having a thickness of about 0.025 millimeters. These plastic materials are thermoformable and biocompatable with the human eye. The two shaped lenses are bonded together with a variety of procedures which may include thermosetting and solvent based adhesives, laser and impulse welding, and ultrasonic bonding. The fill tube, which is used to inject a refractive filling material is formed with the lens so as not to damage the lens shape. A hypodermic tube may be included inside the fill tube.

  12. Intraocular lens fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Salazar, M.A.; Foreman, L.R.

    1997-07-08

    This invention describes a method for fabricating an intraocular lens made from clear Teflon{trademark}, Mylar{trademark}, or other thermoplastic material having a thickness of about 0.025 millimeters. These plastic materials are thermoformable and biocompatable with the human eye. The two shaped lenses are bonded together with a variety of procedures which may include thermosetting and solvent based adhesives, laser and impulse welding, and ultrasonic bonding. The fill tube, which is used to inject a refractive filling material is formed with the lens so as not to damage the lens shape. A hypodermic tube may be included inside the fill tube. 13 figs.

  13. Mask fabrication process

    Science.gov (United States)

    Cardinale, Gregory F.

    2000-01-01

    A method for fabricating masks and reticles useful for projection lithography systems. An absorber layer is conventionally patterned using a pattern and etch process. Following the step of patterning, the entire surface of the remaining top patterning photoresist layer as well as that portion of an underlying protective photoresist layer where absorber material has been etched away is exposed to UV radiation. The UV-exposed regions of the protective photoresist layer and the top patterning photoresist layer are then removed by solution development, thereby eliminating the need for an oxygen plasma etch and strip and chances for damaging the surface of the substrate or coatings.

  14. Advanced fabrication technology

    International Nuclear Information System (INIS)

    Sheely, W.F.

    1986-01-01

    The Fuel Cycle Plant is a multipurpose nuclear facility located on the Hanford Nuclear Reservation in eastern Washington state. The facility is part of the Hanford Engineering Development Laboratory which is operated by Westinghouse Hanford Company for the Department of Energy. The Fuel Cycle Plant is currently being prepared to support the Liquid Metal Reactors Program with fuel fabrication services for the Fast Flux Test Facility and other LMR programs. This report describes the technical innovations to be utilized in the operation of this plant

  15. Resistance switching memory in perovskite oxides

    International Nuclear Information System (INIS)

    Yan, Z.B.; Liu, J.-M.

    2015-01-01

    The resistance switching behavior has recently attracted great attentions for its application as resistive random access memories (RRAMs) due to a variety of advantages such as simple structure, high-density, high-speed and low-power. As a leading storage media, the transition metal perovskite oxide owns the strong correlation of electrons and the stable crystal structure, which brings out multifunctionality such as ferroelectric, multiferroic, superconductor, and colossal magnetoresistance/electroresistance effect, etc. The existence of rich electronic phases, metal–insulator transition and the nonstoichiometric oxygen in perovskite oxide provides good platforms to insight into the resistive switching mechanisms. In this review, we first introduce the general characteristics of the resistance switching effects, the operation methods and the storage media. Then, the experimental evidences of conductive filaments, the transport and switching mechanisms, and the memory performances and enhancing methods of perovskite oxide based filamentary RRAM cells have been summarized and discussed. Subsequently, the switching mechanisms and the performances of the uniform RRAM cells associating with the carrier trapping/detrapping and the ferroelectric polarization switching have been discussed. Finally, the advices and outlook for further investigating the resistance switching and enhancing the memory performances are given

  16. Reluctance motor employing superconducting magnetic flux switches

    International Nuclear Information System (INIS)

    Spyker, R.L.; Ruckstadter, E.J.

    1992-01-01

    This paper reports that superconducting flux switches controlling the magnetic flux in the poles of a motor will enable the implementation of a reluctance motor using one central single phase winding. A superconducting flux switch consists of a ring of superconducting material surrounding a ferromagnetic pole of the motor. When in the superconducting state the switch will block all magnetic flux attempting to flow in the ferromagnetic core. When switched to the normal state the superconducting switch will allow the magnetic flux to flow freely in that pole. By using one high turns-count coil as a flux generator, and selectively channeling flux among the various poles using the superconducting flux switch, 3-phase operation can be emulated with a single-hase central AC source. The motor will also operate when the flux generating coil is driven by a DC current, provided the magnetic flux switches see a continuously varying magnetic flux. Rotor rotation provides this varying flux due to the change in stator pole inductance it produces

  17. Bulk chirality effect for symmetric bistable switching of liquid crystals on topologically self-patterned degenerate anchoring surface.

    Science.gov (United States)

    Park, Min-Kyu; Joo, Kyung-Il; Kim, Hak-Rin

    2017-06-26

    We demonstrate a bistable switching liquid crystal (LC) mode utilizing a topologically self-structured dual-groove surface for degenerated easy axes of LC anchoring. In our study, the effect of the bulk elastic distortion of the LC directors on the bistable anchoring surface is theoretically analyzed for balanced bistable states based on a free energy diagram. By adjusting bulk LC chirality, we developed ideally symmetric and stable bistable anchoring and switching properties, which can be driven by a low in-plane pulsed field of about 0.7 V/µm. The fabricated device has a contrast ratio of 196:1.

  18. A linear 180 nm SOI CMOS antenna switch module using integrated passive device filters for cellular applications

    Science.gov (United States)

    Jie, Cui; Lei, Chen; Peng, Zhao; Xu, Niu; Yi, Liu

    2014-06-01

    A broadband monolithic linear single pole, eight throw (SP8T) switch has been fabricated in 180 nm thin film silicon-on-insulator (SOI) CMOS technology with a quad-band GSM harmonic filter in integrated passive devices (IPD) technology, which is developed for cellular applications. The antenna switch module (ASM) features 1.2 dB insertion loss with filter on 2G bands and 0.4 dB insertion loss in 3G bands, less than -45 dB isolation and maximum -103 dB intermodulation distortion for mobile front ends by applying distributed architecture and adaptive supply voltage generator.

  19. A linear 180 nm SOI CMOS antenna switch module using integrated passive device filters for cellular applications

    International Nuclear Information System (INIS)

    Cui Jie; Chen Lei; Liu Yi; Zhao Peng; Niu Xu

    2014-01-01

    A broadband monolithic linear single pole, eight throw (SP8T) switch has been fabricated in 180 nm thin film silicon-on-insulator (SOI) CMOS technology with a quad-band GSM harmonic filter in integrated passive devices (IPD) technology, which is developed for cellular applications. The antenna switch module (ASM) features 1.2 dB insertion loss with filter on 2G bands and 0.4 dB insertion loss in 3G bands, less than −45 dB isolation and maximum −103 dB intermodulation distortion for mobile front ends by applying distributed architecture and adaptive supply voltage generator. (semiconductor integrated circuits)

  20. Subnanosecond photoconductive switching in GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Druce, R.L.; Pocha, M.D.; Griffin, K.L.

    1991-04-01

    We are conducting research in photoconductive switching for the purpose of generating microwave pulses with amplitudes up to 50 kV. This technology has direct application to impulse radar and HPM sources. We are exploiting the very fast recombination rates of Gallium Arsenide (GaAs) to explore the potential of GaAs as an on-off switch when operating in the linear mode (the linear mode is defined such that one carrier pair is generated for each photon absorbed). In addition, we are exploring the potential GaAs to act as a closing switch in ``avalanche`` mode at high fields. We have observed switch closing times of less than 200 psec with a 100 psec duration laser pulse and opening times of less than 400 psec with neutron irradiated GaAs at fields of tens of kV/cm. If the field is increased and the laser energy decreased, the laser can be used to trigger photoconductive switches into ``avalanche`` mode of operation in which carrier multiplication occurs. This mode of operation is quite promising since the switches close in less than 1 nsec while realizing significant energy gain (ratio of electrical energy in the pulse to optical trigger energy). We are currently investigating both large area (1 sq cm) and small area (< 1 sq mm) switches illuminated by GaAlAs laser diodes at 900 nm and Nd:YAG lasers at 1.06 micrometers. Preliminary results indicate that the closing time of the avalanche switches depends primarily on the material properties of the devices with closing times of 300--1300 psec at voltages of 6--35 kV. We will present experimental results for linear, lock on and avalanche mode operation of GaAs photoconductive switches and how these pulses may be applied to microwave generation. 3 refs.

  1. Subnanosecond photoconductive switching in GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Druce, R.L.; Pocha, M.D.; Griffin, K.L.

    1991-04-01

    We are conducting research in photoconductive switching for the purpose of generating microwave pulses with amplitudes up to 50 kV. This technology has direct application to impulse radar and HPM sources. We are exploiting the very fast recombination rates of Gallium Arsenide (GaAs) to explore the potential of GaAs as an on-off switch when operating in the linear mode (the linear mode is defined such that one carrier pair is generated for each photon absorbed). In addition, we are exploring the potential GaAs to act as a closing switch in avalanche'' mode at high fields. We have observed switch closing times of less than 200 psec with a 100 psec duration laser pulse and opening times of less than 400 psec with neutron irradiated GaAs at fields of tens of kV/cm. If the field is increased and the laser energy decreased, the laser can be used to trigger photoconductive switches into avalanche'' mode of operation in which carrier multiplication occurs. This mode of operation is quite promising since the switches close in less than 1 nsec while realizing significant energy gain (ratio of electrical energy in the pulse to optical trigger energy). We are currently investigating both large area (1 sq cm) and small area (< 1 sq mm) switches illuminated by GaAlAs laser diodes at 900 nm and Nd:YAG lasers at 1.06 micrometers. Preliminary results indicate that the closing time of the avalanche switches depends primarily on the material properties of the devices with closing times of 300--1300 psec at voltages of 6--35 kV. We will present experimental results for linear, lock on and avalanche mode operation of GaAs photoconductive switches and how these pulses may be applied to microwave generation. 3 refs.

  2. Subnanosecond photoconductive switching in GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Druce, R.L.; Pocha, M.D.; Griffin, K.L.

    1990-01-01

    We are conducting research in photoconductive switching for the purpose of generating microwave pulses with amplitudes up to 50 kV. This technology has direct application to impulse radar and HPM sources. We are exploiting the very fast recombination rates of Gallium Arsenide (GaAs) to explore the potential of GaAs as an on-off switch when operating in the linear mode (the linear mode is defined such that one carrier pair is generated for each photon absorbed). In addition, we are exploring the potential of GaAs to act as a closing switch in avalanche'' mode at high fields. We have observed switch closing times of less than 200 psec with 100 psec duration laser pulse and opening times of less than 400 psec with neutron irradiated GaAs at fields of tens of kV/cm. If the field is increased and the laser energy decreased, the laser can be used to trigger photoconductive switches into an avalanche'' mode of operation in which carrier multiplication occurs. This mode of operation is quite promising since the switches close in less than 1 nsec while realizing significant energy gain (ratio of electrical energy in the pulse to optical trigger energy). We are currently investigating both large are (1 sq cm) and small area (<1 sq mm) switches illuminated by GaAlAs laser diodes at 900 nm and Nd:YAG lasers at 1.06 micrometers. Preliminary results indicate that the closing time of the avalanche switches depends primarily on the material properties of the devices with closing times of 300--1300 psec at voltages of 6-35 kV. We will present experimental results for linear, lock on and avalanche mode operation of GaAs photoconductive switches and how these pulses may be applied to microwave generation. 3 refs., 11 figs.

  3. Subnanosecond photoconductive switching in GaAs

    Science.gov (United States)

    Druce, R. L.; Pocha, M. D.; Griffin, K. L.

    1991-04-01

    We are conducting research in photoconductive switching for the purpose of generating microwave pulses with amplitudes up to 50 kV. This technology has direct application to impulse radar and HPM sources. We are exploiting the very fast recombination rates of Gallium Arsenide (GaAs) to explore the potential of GaAs as an on-off switch when operating in the linear mode (the linear mode is defined such that one carrier pair is generated for each photon absorbed). In addition, we are exploring the potential GaAs to act as a closing switch in 'avalanche' mode at high fields. We have observed switch closing times of less than 200 psec with a 100 psec duration laser pulse and opening times of less than 400 psec with neutron irradiated GaAs at fields of tens of kV/cm. If the field is increased and the laser energy decreased, the laser can be used to trigger photoconductive switches into 'avalanche' mode of operation in which carrier multiplication occurs. This mode of operation is quite promising since the switches close in less than 1 nsec while realizing significant energy gain (ratio of electrical energy in the pulse to optical trigger energy). We are currently investigating both large area (1 sq cm) and small area (less than 1 sq mm) switches illuminated by GaAlAs laser diodes at 900 nm and Nd:YAG lasers at 1.06 micrometers. Preliminary results indicate that the closing time of the avalanche switches depends primarily on the material properties of the devices with closing times of 300-1300 psec at voltages of 6-35 kV. We will present experimental results for linear, lock on, and avalanche mode operation of GaAs photoconductive switches and how these pulses may be applied to microwave generation.

  4. Organization of the channel-switching process in parallel computer systems based on a matrix optical switch

    Science.gov (United States)

    Golomidov, Y. V.; Li, S. K.; Popov, S. A.; Smolov, V. B.

    1986-01-01

    After a classification and analysis of electronic and optoelectronic switching devices, the design principles and structure of a matrix optical switch is described. The switching and pair-exclusion operations in this type of switch are examined, and a method for the optical switching of communication channels is elaborated. Finally, attention is given to the structural organization of a parallel computer system with a matrix optical switch.

  5. DESAIN DAN IMPLEMENTSI SOFT SWITCHING BOOST KONVERTER DENGAN SIMPLE AUXILLARY RESONANT SWITCH (SARC

    Directory of Open Access Journals (Sweden)

    Dimas Bagus Saputra

    2017-01-01

    Full Text Available Boost konverter merupakan penaik tegangan DC ke tegangan DC yang mempunyai tegangan output yang lebih tinggi dibanding inputnya. Penggunaan boost konverter diera modern semakin meningkat dan dibuat dengan dimensi yang lebih kecil, berat yang lebih ringan dan efisiensi yang lebih tinggi dibanding dengan boost konverter generasi terdahulu. Tetapi rugi-rugi periodik saat on/off meningkat. Untuk meraih kriteria tersebut, teknik hard switching boost konverter berevolusi menjadi teknik soft switching dengan menambah rangkaian simple auxiliary resonant circuit (SARC. Karena penambahan rangkaian SARC tersebut konverter bekerja pada kondisi zero-voltage switching switch (ZVS dan zero current switch (ZCS, sehingga saklar semikonduktor tidak bekerja secara hard switching lagi. Pada penelitian ini akan di desain dan diimplementaskan soft switching boost konverter dengan SARC. Kelebihan dari soft switching boost konverter dengan SARC adalah mempunyai efisiensi yang lebih tinggi dibanding dengan boost konverter konventional. Dari hasil implementasi menunjukkan konverter yang diajukan telah meraih zero voltage switch (ZVS. Sehingga boost konverter zero voltage switch (ZVS bisa diaplikasikan pada sistem power suplay yang membutuhkan efisiensi energi yang tinggi terutama pada daya yang tinggi.

  6. Comparison of switching control algorithms effective in restricting the switching in the neighborhood of the origin

    International Nuclear Information System (INIS)

    Joung, JinWook; Chung, Lan; Smyth, Andrew W

    2010-01-01

    The active interaction control (AIC) system consisting of a primary structure, an auxiliary structure and an interaction element was proposed to protect the primary structure against earthquakes and winds. The objective of the AIC system in reducing the responses of the primary structure is fulfilled by activating or deactivating the switching between the engagement and the disengagement of the primary and auxiliary structures through the interaction element. The status of the interaction element is controlled by switching control algorithms. The previously developed switching control algorithms require an excessive amount of switching, which is inefficient. In this paper, the excessive amount of switching is restricted by imposing an appropriately designed switching boundary region, where switching is prohibited, on pre-designed engagement–disengagement conditions. Two different approaches are used in designing the newly proposed AID-off and AID-off 2 algorithms. The AID-off 2 algorithm is designed to affect deactivated switching regions explicitly, unlike the AID-off algorithm, which follows the same procedure of designing the engagement–disengagement conditions of the previously developed algorithms, by using the current status of the AIC system. Both algorithms are shown to be effective in reducing the amount of switching times triggered from the previously developed AID algorithm under an appropriately selected control sampling period for different earthquakes, but the AID-off 2 algorithm outperforms the AID-off algorithm in reducing the number of switching times

  7. Effects of doping concentration ratio on electrical characterization in pseudomorphic HEMT-based MMIC switches for ICT system

    Science.gov (United States)

    Mun, Jae-Kyoung; Oh, Jung-Hun; Sung, Ho-Kun; Wang, Cong

    2015-12-01

    The effects of the doping concentration ratios between upper and lower silicon planar-doping layers on the DC and RF characteristics of the double planar doped pseudomorphic high electron mobility transistors (pHEMTs) are investigated. From the device simulation, an increase of maximum extrinsic transconductance and a decrease of total on- and off-state capacitances are observed, as well as an increase of the upper to lower planar-doping concentration ratios (UTLPDR), which give rise to an enhancement of the switching speed and isolation characteristics. On the basis of simulation results, two types of pHEMTs are fabricated with two different UTLPDRs of 4:1 and 1:2. After applying these two types' pHEMTs, single-pole-double-throw (SPDT) transmitter/receiver monolithic microwave integrated circuit (MMIC) switches are also designed and fabricated. The SPDT MMIC switch with a 4:1 UTLPDR shows an insertion loss of 0.58 dB, isolation of 40.2 dB, and switching speed of 100 ns, respectively, which correspondingly indicate a 0.23 dB lower insertion loss, 2.90 dB higher isolation and 2.5 times faster switching speed than those of 1:2 UTLPDR at frequency range of 2-6 GHz. From the simulation results and comparative studies, we propose that the UTLPDR must be greater than 4:1 for the best switching performance. With the abovementioned excellent performances, the proposed switch would be quite promising in the application of information and communications technology system.

  8. Exponential Stability of Switched Positive Homogeneous Systems

    Directory of Open Access Journals (Sweden)

    Dadong Tian

    2017-01-01

    Full Text Available This paper studies the exponential stability of switched positive nonlinear systems defined by cooperative and homogeneous vector fields. In order to capture the decay rate of such systems, we first consider the subsystems. A sufficient condition for exponential stability of subsystems with time-varying delays is derived. In particular, for the corresponding delay-free systems, we prove that this sufficient condition is also necessary. Then, we present a sufficient condition of exponential stability under minimum dwell time switching for the switched positive nonlinear systems. Some results in the previous literature are extended. Finally, a numerical example is given to demonstrate the effectiveness of the obtained results.

  9. High voltage superconducting switch for power application

    International Nuclear Information System (INIS)

    Mawardi, O.; Ferendeci, A.; Gattozzi, A.

    1983-01-01

    This paper reports the development of a novel interrupter which meets the requirements of a high voltage direct current (HVDC) power switch and at the same time doubles as a current limiter. The basic concept of the interrupter makes use of a fast superconducting, high capacity (SHIC) switch that carries the full load current while in the superconducting state and reverts to the normal resistive state when triggered. Typical design parameters are examined for the case of a HVDC transmission line handling 2.5KA at 150KVDC. The result is a power switch with superior performance and smaller size than the ones reported to date

  10. Consumer poaching, brand switching, and price transparency

    DEFF Research Database (Denmark)

    Schultz, Christian

    2014-01-01

    This paper addresses price transparency on the consumer side in markets with behavioral price discrimination which feature welfare reducing brand switching. When long-term contracts are not available, an increase in transparency intensifies competition, lowers prices and profits, reduces brand...... switching and benefits consumers and welfare. With long-term contracts, an increase in transparency reduces the use of long-term contracts, leading to more brand switching and a welfare loss. Otherwise, the results are the same as without long-term contracts....

  11. Electrically switched cesium ion exchange

    International Nuclear Information System (INIS)

    Lilga, M.A.; Orth, R.J.; Sukamto, J.P.H.; Schwartz, D.T.; Haight, S.M.; Genders, J.D.

    1997-04-01

    Electrically Switched Ion Exchange (ESIX) is a separation technology being developed as an alternative to conventional ion exchange for removing radionuclides from high-level waste. The ESIX technology, which combines ion exchange and electrochemistry, is geared toward producing electroactive films that are highly selective, regenerable, and long lasting. During the process, ion uptake and elution are controlled directly by modulating the potential of an ion exchange film that has been electrochemically deposited onto a high surface area electrode. This method adds little sodium to the waste stream and minimizes the secondary wastes associated with traditional ion exchange techniques. Development of the ESIX process is well underway for cesium removal using ferrocyanides as the electroactive films. Films having selectivity for perrhenate (a pertechnetate surrogate) over nitrate also have been deposited and tested. A case study for the KE Basin on the Hanford Site was conducted based on the results of the development testing. Engineering design baseline parameters for film deposition, film regeneration, cesium loading, and cesium elution were used for developing a conceptual system. Order of magnitude cost estimates were developed to compare with conventional ion exchange. This case study demonstrated that KE Basin wastewater could be processed continuously with minimal secondary waste and reduced associated disposal costs, as well as lower capital and labor expenditures

  12. Fabrication of zein nanostructure

    Science.gov (United States)

    Luecha, Jarupat

    The concerns on the increase of polluting plastic wastes as well as the U.S. dependence on imported petrochemical products have driven an attention towards alternative biodegradable polymers from renewable resources. Zein protein, a co-product from ethanol production from corn, is a good candidate. This research project aims to increase zein value by adopting nanotechnology for fabricating advanced zein packaging films and zein microfluidic devices. Two nanotechnology approaches were focused: the polymer nanoclay nanocomposite technique where the nanocomposite structures were created in the zein matrix, and the soft lithography and the microfluidic devices where the micro and nanopatterns were created on the zein film surfaces. The polymer nanoclay nanocomposite technique was adopted in the commonly used zein film fabrication processes which were solvent casting and extrusion blowing methods. The two methods resulted in partially exfoliated nanocomposite structures. The impact of nanoclays on the physical properties of zein films strongly depended on the film preparation techniques. The impact of nanoclay concentration was more pronounced in the films made by extrusion blowing technique than by the solvent casting technique. As the processability limitation for the extrusion blowing technique of the zein sample containing hight nanoclay content, the effect of the nanoclay content on the rheological properties of zein hybrid resins at linear and nonlinear viscoelastic regions were further investigated. A pristine zein resin exhibited soft solid like behavior. On the other hand, the zein hybrid with nanoclay content greater than 5 wt.% showed more liquid like behavior, suggesting that the nanoclays interrupted the entangled zein network. There was good correspondence between the experimental data and the predictions of the Wagner model for the pristine zein resins. However, the model failed to predict the steady shear properties of the zein nanoclay nanocomposite

  13. Fabrication of Pb (Zr, Ti) O3 Thin Film for Non-Volatile Memory Device Application

    International Nuclear Information System (INIS)

    Mar Lar Win

    2011-12-01

    Ferroelectric lead zirconate titanate powder was composed of mainly the oxides of titanium, zirconium and lead. PZT powder was firstly prepared by thermal synthesis at different Zr/Ti ratios with various sintering temperatures. PZT thin film was fabricated on SiO2/Si substrate by using thermal evaporation method. Physical and elemental analysis were carried out by using SEM, EDX and XRD The ferroelectric properties and the switching behaviour of the PZT thin films were investigated. The ferroelectric properties and switching properties of the PZT thin film (near morphotropic phase boundary sintered at 800 C) could function as a nonvolatile memory.

  14. Controllability of multi-agent systems with periodically switching topologies and switching leaders

    Science.gov (United States)

    Tian, Lingling; Zhao, Bin; Wang, Long

    2018-05-01

    This paper considers controllability of multi-agent systems with periodically switching topologies and switching leaders. The concept of m-periodic controllability is proposed, and a criterion for m-periodic controllability is established. The effect of the duration of subsystems on controllability is analysed by utilising a property of analytic functions. In addition, the influence of switching periods on controllability is investigated, and an algorithm is proposed to search for the fewest periods to ensure controllability. A necessary condition for m-periodic controllability is obtained from the perspective of eigenvectors of the subsystems' Laplacian matrices. For a system with switching leaders, it is proved that switching-leader controllability is equivalent to multiple-leader controllability. Furthermore, both the switching order and the tenure of agents being leaders have no effect on the controllability. Some examples are provided to illustrate the theoretical results.

  15. Instability in time-delayed switched systems induced by fast and random switching

    Science.gov (United States)

    Guo, Yao; Lin, Wei; Chen, Yuming; Wu, Jianhong

    2017-07-01

    In this paper, we consider a switched system comprising finitely or infinitely many subsystems described by linear time-delayed differential equations and a rule that orchestrates the system switching randomly among these subsystems, where the switching times are also randomly chosen. We first construct a counterintuitive example where even though all the time-delayed subsystems are exponentially stable, the behaviors of the randomly switched system change from stable dynamics to unstable dynamics with a decrease of the dwell time. Then by using the theories of stochastic processes and delay differential equations, we present a general result on when this fast and random switching induced instability should occur and we extend this to the case of nonlinear time-delayed switched systems as well.

  16. Programming Nanoparticles in Multiscale: Optically Modulated Assembly and Phase Switching of Silicon Nanoparticle Array.

    Science.gov (United States)

    Wang, Letian; Rho, Yoonsoo; Shou, Wan; Hong, Sukjoon; Kato, Kimihiko; Eliceiri, Matthew; Shi, Meng; Grigoropoulos, Costas P; Pan, Heng; Carraro, Carlo; Qi, Dongfeng

    2018-03-27

    Manipulating and tuning nanoparticles by means of optical field interactions is of key interest for nanoscience and applications in electronics and photonics. We report scalable, direct, and optically modulated writing of nanoparticle patterns (size, number, and location) of high precision using a pulsed nanosecond laser. The complex nanoparticle arrangement is modulated by the laser pulse energy and polarization with the particle size ranging from 60 to 330 nm. Furthermore, we report fast cooling-rate induced phase switching of crystalline Si nanoparticles to the amorphous state. Such phase switching has usually been observed in compound phase change materials like GeSbTe. The ensuing modification of atomic structure leads to dielectric constant switching. Based on these effects, a multiscale laser-assisted method of fabricating Mie resonator arrays is proposed. The number of Mie resonators, as well as the resonance peaks and dielectric constants of selected resonators, can be programmed. The programmable light-matter interaction serves as a mechanism to fabricate optical metasurfaces, structural color, and multidimensional optical storage devices.

  17. Analysis of Switched-Rigid Floating Oscillator

    Directory of Open Access Journals (Sweden)

    Prabhakar R. Marur

    2009-01-01

    Full Text Available In explicit finite element simulations, a technique called deformable-to-rigid (D2R switching is used routinely to reduce the computation time. Using the D2R option, the deformable parts in the model can be switched to rigid and reverted back to deformable when needed during the analysis. The time of activation of D2R however influences the overall dynamics of the system being analyzed. In this paper, a theoretical basis for the selection of time of rigid switching based on system energy is established. A floating oscillator problem is investigated for this purpose and closed-form analytical expressions are derived for different phases in rigid switching. The analytical expressions are validated by comparing the theoretical results with numerical computations.

  18. Multi-planed unified switching topologies

    Science.gov (United States)

    Chen, Dong; Heidelberger, Philip; Sugawara, Yutaka

    2017-07-04

    An apparatus and method for extending the scalability and improving the partitionability of networks that contain all-to-all links for transporting packet traffic from a source endpoint to a destination endpoint with low per-endpoint (per-server) cost and a small number of hops. An all-to-all wiring in the baseline topology is decomposed into smaller all-to-all components in which each smaller all-to-all connection is replaced with star topology by using global switches. Stacking multiple copies of the star topology baseline network creates a multi-planed switching topology for transporting packet traffic. Point-to-point unified stacking method using global switch wiring methods connects multiple planes of a baseline topology by using the global switches to create a large network size with a low number of hops, i.e., low network latency. Grouped unified stacking method increases the scalability (network size) of a stacked topology.

  19. Nano- and micro-electromechanical switch dynamics

    International Nuclear Information System (INIS)

    Pulskamp, Jeffrey S; Proie, Robert M; Polcawich, Ronald G

    2013-01-01

    This paper reports theoretical analysis and experimental results on the dynamics of piezoelectric MEMS mechanical logic relays. The multiple degree of freedom analytical model, based on modal decomposition, utilizes modal parameters obtained from finite element analysis and an analytical model of piezoelectric actuation. The model accounts for exact device geometry, damping, drive waveform variables, and high electric field piezoelectric nonlinearity. The piezoelectrically excited modal force is calculated directly and provides insight into design optimization for switching speed. The model accurately predicts the propagation delay dependence on actuation voltage of mechanically distinct relay designs. The model explains the observed discrepancies in switching speed of these devices relative to single degree of freedom switching speed models and suggests the strong potential for improved switching speed performance in relays designed for mechanical logic and RF circuits through the exploitation of higher order vibrational modes. (paper)

  20. Proton-Controlled Organic Microlaser Switch.

    Science.gov (United States)

    Gao, Zhenhua; Zhang, Wei; Yan, Yongli; Yi, Jun; Dong, Haiyun; Wang, Kang; Yao, Jiannian; Zhao, Yong Sheng

    2018-05-25

    Microscale laser switches have been playing irreplaceable roles in the development of photonic devices with high integration levels. However, it remains a challenge to switch the lasing wavelengths across a wide range due to relatively fixed energy bands in traditional semiconductors. Here, we report a strategy to switch the lasing wavelengths among multiple states based on a proton-controlled intramolecular charge-transfer (ICT) process in organic dye-doped flexible microsphere resonant cavities. The protonic acids can effectively bind onto the ICT molecules, which thus enhance the ICT strength of the dyes and lead to a red-shifted gain behavior. On this basis, the gain region was effectively modulated by using acids with different proton-donating ability, and as a result, laser switching among multiple wavelengths was achieved. The results will provide guidance for the rational design of miniaturized lasers with performances based on the characteristic of organic optoelectronic materials.

  1. Delayed switching applied to memristor neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Frank Z.; Yang Xiao; Lim Guan [Future Computing Group, School of Computing, University of Kent, Canterbury (United Kingdom); Helian Na [School of Computer Science, University of Hertfordshire, Hatfield (United Kingdom); Wu Sining [Xyratex, Havant (United Kingdom); Guo Yike [Department of Computing, Imperial College, London (United Kingdom); Rashid, Md Mamunur [CERN, Geneva (Switzerland)

    2012-04-01

    Magnetic flux and electric charge are linked in a memristor. We reported recently that a memristor has a peculiar effect in which the switching takes place with a time delay because a memristor possesses a certain inertia. This effect was named the ''delayed switching effect.'' In this work, we elaborate on the importance of delayed switching in a brain-like computer using memristor neural networks. The effect is used to control the switching of a memristor synapse between two neurons that fire together (the Hebbian rule). A theoretical formula is found, and the design is verified by a simulation. We have also built an experimental setup consisting of electronic memristive synapses and electronic neurons.

  2. Delayed switching applied to memristor neural networks

    International Nuclear Information System (INIS)

    Wang, Frank Z.; Yang Xiao; Lim Guan; Helian Na; Wu Sining; Guo Yike; Rashid, Md Mamunur

    2012-01-01

    Magnetic flux and electric charge are linked in a memristor. We reported recently that a memristor has a peculiar effect in which the switching takes place with a time delay because a memristor possesses a certain inertia. This effect was named the ''delayed switching effect.'' In this work, we elaborate on the importance of delayed switching in a brain-like computer using memristor neural networks. The effect is used to control the switching of a memristor synapse between two neurons that fire together (the Hebbian rule). A theoretical formula is found, and the design is verified by a simulation. We have also built an experimental setup consisting of electronic memristive synapses and electronic neurons.

  3. A nanoplasmonic switch based on molecular machines

    KAUST Repository

    Zheng, Yue Bing; Yang, Ying-Wei; Jensen, Lasse; Fang, Lei; Juluri, Bala Krishna; Weiss, Paul S.; Stoddart, J. Fraser; Huang, Tony Jun

    2009-01-01

    We aim to develop a molecular-machine-driven nanoplasmonic switch for its use in future nanophotonic integrated circuits (ICs) that have applications in optical communication, information processing, biological and chemical sensing. Experimental

  4. Topological photonic orbital-angular-momentum switch

    Science.gov (United States)

    Luo, Xi-Wang; Zhang, Chuanwei; Guo, Guang-Can; Zhou, Zheng-Wei

    2018-04-01

    The large number of available orbital-angular-momentum (OAM) states of photons provides a unique resource for many important applications in quantum information and optical communications. However, conventional OAM switching devices usually rely on precise parameter control and are limited by slow switching rate and low efficiency. Here we propose a robust, fast, and efficient photonic OAM switch device based on a topological process, where photons are adiabatically pumped to a target OAM state on demand. Such topological OAM pumping can be realized through manipulating photons in a few degenerate main cavities and involves only a limited number of optical elements. A large change of OAM at ˜10q can be realized with only q degenerate main cavities and at most 5 q pumping cycles. The topological photonic OAM switch may become a powerful device for broad applications in many different fields and motivate a topological design of conventional optical devices.

  5. Switching overvoltages in offshore wind power grids

    DEFF Research Database (Denmark)

    Arana Aristi, Ivan

    and cables are presented. In Chapter 4 results from time domain measurements and simulations of switching operations in offshore wind power grids are described. Specifically, switching operations on a single wind turbine, the collection grid, the export system and the external grid measured in several real...... offshore wind farms are shown together with simulation results. Switching operations in offshore wind power grids can be simulated with different electromagnetic transient programs. Different programs were used in the project and compared results are included in Chapter 4. Also in Chapter 4 different......Switching transients in wind turbines, the collection grid, the export system and the external grid in offshore wind farms, during normal or abnormal operation, are the most important phenomena when conducting insulation coordination studies. However, the recommended models and methods from...

  6. Bistable fluidic valve is electrically switched

    Science.gov (United States)

    Fiet, O.; Salvinski, R. J.

    1970-01-01

    Bistable control valve is selectively switched by direct application of an electrical field to divert fluid from one output channel to another. Valve is inexpensive, has no moving parts, and operates on fluids which are relatively poor electrical conductors.

  7. Modeling switching behaviour of direct selling customers

    Directory of Open Access Journals (Sweden)

    P Msweli-Mbanga

    2004-04-01

    Full Text Available The direct selling industry suffers a high turnover rate of salespeople, resulting in high costs of training new salespeople. Further costs are incurred when broken relationships with customers cause them to switch from one product supplier to another. This study identifies twelve factors that drive the switching behaviour of direct sales customers and examines the extent to which these factors influence switching. Exploratory factor analysis was used to assess the validity of these factors. The factors were represented in a model that posits that an interpersonal relationship between a direct sales person and a customer moderates the relationship between switching behaviour and loyalty. Structural equation modeling was used to test the proposed model. The author then discusses the empirical findings and their managerial implications, providing further avenues for research.

  8. Active plasmonics in WDM traffic switching applications

    DEFF Research Database (Denmark)

    Papaioannou, S.; Kalavrouziotis, D.; Vyrsokinos, K.

    2012-01-01

    -enabling characteristics of active plasmonic circuits with an ultra-low power 3 response time product represents a crucial milestone in the development of active plasmonics towards real telecom and datacom applications, where low-energy and fast TO operation with small-size circuitry is targeted........ The first active Dielectric-Loaded Surface Plasmon Polariton (DLSPP) thermo-optic (TO) switches with successful performance in single-channel 10 Gb/s data traffic environments have led the inroad towards bringing low-power active plasmonics in practical traffic applications. In this article, we introduce...... active plasmonics into Wavelength Division Multiplexed (WDM) switching applications, using the smallest TO DLSPP-based Mach-Zehnder interferometric switch reported so far and showing its successful performance in 4310 Gb/s low-power and fast switching operation. The demonstration of the WDM...

  9. Theoretical model for plasma opening switch

    International Nuclear Information System (INIS)

    Baker, L.

    1980-07-01

    The theory of an explosive plasma switch is developed and compared with the experimental results of Pavlovskii and work at Sandia. A simple analytic model is developed, which predicts that such switches may achieve opening times of approximately 100 ns. When the switching time is limited by channel mixing it scales as t = C(m d 0 )/sup 1/2/P 0 2 P/sub e//sup -5/2/ where m is the foil mass per unit area, d 0 the channel thickness and P 0 the channel pressure (at explosive breakout), P/sub e/ the explosive pressure, C a constant of order 10 for c.g.s. units. Thus faster switching times may be achieved by minimizing foil mass and channel pressure, or increasing explosive product pressure, with the scaling exponents as shown suggesting that changes in pressures would be more effective

  10. Blood and Books: Performing Code Switching

    Directory of Open Access Journals (Sweden)

    Jeff Friedman

    2008-05-01

    Full Text Available Code switching is a linguistic term that identifies ways individuals use communication modes and registers to negotiate difference in social relations. This essay suggests that arts-based inquiry, in the form of choreography and performance, provides a suitable and efficacious location within which both verbal and nonverbal channels of code switching can be investigated. Blood and Books, a case study of dance choreography within the context of post-colonial Maori performance in Aotearoa/New Zealand, is described and analyzed for its performance of code switching. The essay is framed by a discussion of how arts-based research within tertiary higher education requires careful negotiation in the form of code switching, as performed by the author's reflexive use of vernacular and formal registers in the essay. URN: urn:nbn:de:0114-fqs0802462

  11. Resistivity switching properties of Li-doped ZnO films deposited on LaB_6 electrode

    International Nuclear Information System (INIS)

    Igityan, A.; Kafadaryan, Y.; Aghamalyan, N.; Petrosyan, S.; Badalyan, G.; Vardanyan, V.; Nersisyan, M.; Hovsepyan, R.; Palagushkin, A.; Kryzhanovsky, B.

    2015-01-01

    Current–voltage (I–V) characteristics of Al/p-ZnO:Li/LaB_6 device, measured in voltage sweep mode, show unipolar resistive switching and monostable threshold switching (URS and MTS) for different bias voltage polarities. URS could be transformed to MTS by application of reverse bias voltage. With increasing number of cycles, URS is converted to bipolar resistive switching mode which is lost after certain number of cycles, and device turns into an ordinary resistor. Analysis of linear fitting I–V curves suggests that ohmic and space charge limited current laws are responsible for conductivity mechanism of Al/p-ZnO:Li/LaB_6 device. - Highlights: • Al/p-ZnO:Li/LaB_6 memristive device is fabricated using an e-beam evaporation technique. • Current–voltage (I–V) characteristics are studied. • Type of resistive switching mode depends on the bias voltage polarity and number of switching cycles. • Resistive switching in Al/ZnO:Li/LaB_6 has an interfacial effect. • Ohmic and SCLC laws are responsible for conductivity mechanism of resistive states.

  12. Growth and self-assembly of BaTiO3 nanocubes for resistive switching memory cells

    International Nuclear Information System (INIS)

    Chu, Dewei; Lin, Xi; Younis, Adnan; Li, Chang Ming; Dang, Feng; Li, Sean

    2014-01-01

    In this work, the self-assembled BaTiO 3 nanocubes based resistive switching memory capacitors are fabricated with hydrothermal and drop-coating approaches. The device exhibits excellent bipolar resistance switching characteristics with ON/OFF ratio of 58–70, better reliability and stability over various polycrystalline BaTiO 3 nanostructures. It is believed that the inter cube junctions is responsible for such a switching behaviour and it can be described by the filament model. The effect of film thickness on switching ratio (ON/OFF) was also investigated in details. - Graphical abstract: This work describes a novel resistive switching memory cell based on self-assembled BaTiO 3 nanocubes. - Highlights: • BaTiO 3 nanocubes were prepared by one step facile hydrothermal method. • Self-assembled BaTiO 3 nanocubes thin films were obtained by drop-coating approach. • The BaTiO 3 nanocubes show excellent resistive switching properties for memory applications

  13. Subtractive fabrication of ferroelectric thin films with precisely controlled thickness

    Science.gov (United States)

    Ievlev, Anton V.; Chyasnavichyus, Marius; Leonard, Donovan N.; Agar, Joshua C.; Velarde, Gabriel A.; Martin, Lane W.; Kalinin, Sergei V.; Maksymovych, Petro; Ovchinnikova, Olga S.

    2018-04-01

    The ability to control thin-film growth has led to advances in our understanding of fundamental physics as well as to the emergence of novel technologies. However, common thin-film growth techniques introduce a number of limitations related to the concentration of defects on film interfaces and surfaces that limit the scope of systems that can be produced and studied experimentally. Here, we developed an ion-beam based subtractive fabrication process that enables creation and modification of thin films with pre-defined thicknesses. To accomplish this we transformed a multimodal imaging platform that combines time-of-flight secondary ion mass spectrometry with atomic force microscopy to a unique fabrication tool that allows for precise sputtering of the nanometer-thin layers of material. To demonstrate fabrication of thin-films with in situ feedback and control on film thickness and functionality we systematically studied thickness dependence of ferroelectric switching of lead-zirconate-titanate, within a single epitaxial film. Our results demonstrate that through a subtractive film fabrication process we can control the piezoelectric response as a function of film thickness as well as improve on the overall piezoelectric response versus an untreated film.

  14. Error rate degradation due to switch crosstalk in large modular switched optical networks

    DEFF Research Database (Denmark)

    Saxtoft, Christian; Chidgey, P.

    1993-01-01

    A theoretical model of an optical network incorporating wavelength selective elements, amplifiers, couplers and switches is presented. The model is used to evaluate a large modular switch optical network that provides the capability of adapting easily to changes in network traffic requirements. T....... The network dimensions are shown to be limited by the optical crosstalk in the switch matrices and by the polarization dependent loss in the optical components...

  15. Optical Multidimensional Switching for Data Center Networks

    OpenAIRE

    Kamchevska, Valerija; Galili, Michael; Oxenløwe, Leif Katsuo; Berger, Michael Stübert

    2017-01-01

    Optical switches are known for the ability to provide high bandwidth connectivity at a relatively low power consumption and low latency. Several recent demonstrations on optical data center architectures confirm the potential for introducing all-optical switching within the data center, thus avoiding power hungry optical-electrical-optical conversions at each node. This Ph.D. thesis focuses precisely on the application of optical technologies in data center networks where optics is not only u...

  16. High voltage disconnect switch position monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Crampton, S W

    1983-08-01

    Unreliable position indication on high-voltage (HV) disconnect switches can result in equipment damage worth many times the cost of a disconnect switch. The benefits and limitations of a number of possible methods of reliably monitoring HV disconnect switches are assessed. Several methods of powering active devices at HV are noted. It is concluded that the most reliable way of monitoring switch position at reasonable cost would use a passive hermetically-sealed blade-position sensor located at HV, with a fibre-optic link between HV and ground. Separate sensors would be used for open and closed position indication. For maximum reliability the fibre-optic link would continue into the relay building. A passive magnetically actuated fibre-optic sensor has been built which demonstrates the feasibility of the concept. The sensor monitors blade position relative to the jaws in three dimensions with high resolution. A design for an improved passive magneto-optic sensor has significantly lower optical losses, allowing a single fibre-optic loop and 3 sensors to monitor closure of all phases of a disconnect switch. A similar loop would monitor switch opening. The improved sensor has a solid copper housing to provide greater immunity to fault currents, and to protect it from the environment and from physical damage. Two methods of providing a protected path for fibre-optics passing from HV to ground are proposed, one using a hollow porcelain switch-support insulator and the other using an additional small-diameter polymer insulator with optical fibres imbedded in its fibreglass core. A number of improvements are recommended which can be made to existing switches to increase their reliability. 16 refs., 13 figs., 1 tab.

  17. Assessing the Consequences of a Channel Switch

    OpenAIRE

    Xinlei (Jack) Chen; George John; Om Narasimhan

    2008-01-01

    Switching marketing channels is an expensive and sticky decision. While a number of theories suggest efficiency and strategic differences between channels, there is virtually no work on combining these ideas into an empirically workable methodology to assess the impact of a channel switch. In this study, we undertake to close this gap with an empirical study of the sports drink market, featuring competing producers and heterogeneous channels. We estimate demand and cost parameters for a numbe...

  18. Portfolio Selection with Jumps under Regime Switching

    Directory of Open Access Journals (Sweden)

    Lin Zhao

    2010-01-01

    Full Text Available We investigate a continuous-time version of the mean-variance portfolio selection model with jumps under regime switching. The portfolio selection is proposed and analyzed for a market consisting of one bank account and multiple stocks. The random regime switching is assumed to be independent of the underlying Brownian motion and jump processes. A Markov chain modulated diffusion formulation is employed to model the problem.

  19. Lasers for switched-power linacs

    International Nuclear Information System (INIS)

    Bigio, I.J.

    1988-01-01

    Laser-switched power surges for particle accelerators, just as with direct laser-driven accelerator schemes, place unique demands on the specifications of the invoked laser systems. We review the laser requirements for switched power sources of the types described in other chapters of this volume. The relative advantages and disadvantages of selected lasers are listed, and the appropriateness and scalability of existing technology is discussed. 4 refs., 2 figs., 2 tabs

  20. The Robustness of Stochastic Switching Networks

    OpenAIRE

    Loh, Po-Ling; Zhou, Hongchao; Bruck, Jehoshua

    2009-01-01

    Many natural systems, including chemical and biological systems, can be modeled using stochastic switching circuits. These circuits consist of stochastic switches, called pswitches, which operate with a fixed probability of being open or closed. We study the effect caused by introducing an error of size ∈ to each pswitch in a stochastic circuit. We analyze two constructions – simple series-parallel and general series-parallel circuits – and prove that simple series-parallel circuits are robus...

  1. A microcomputer for a packet switched network

    International Nuclear Information System (INIS)

    Seller, P.; Bairstow, R.; Barlow, J.; Waters, M.

    1982-12-01

    The Bubble Chamber Research Group of the Rutherford and Appleton Laboratory has a large film analysis facility. This comprises 16 digitising tables used for the measurement of bubble chamber film. Each of these tables has an associated microcomputer. These microcomputers are linked by a star structured packet switched local area network (LAN) to a VAX 11/780. The LAN, and in particular a microcomputer of novel architecture designed to act as the central switch of the network, is described. (author)

  2. EYE CONTROLLED SWITCHING USING CIRCULAR HOUGH TRANSFORM

    OpenAIRE

    Sagar Lakhmani

    2014-01-01

    The paper presents hands free interface between electrical appliances or devices. This technology is intended to replace conventional switching devices for the use of disabled. It is a new way to interact with the electrical or electronic devices that we use in our daily life. The paper illustrates how the movement of eye cornea and blinking can be used for switching the devices. The basic Circle Detection algorithm is used to determine the position of eye. Eye blinking is used...

  3. Fast simulation techniques for switching converters

    Science.gov (United States)

    King, Roger J.

    1987-01-01

    Techniques for simulating a switching converter are examined. The state equations for the equivalent circuits, which represent the switching converter, are presented and explained. The uses of the Newton-Raphson iteration, low ripple approximation, half-cycle symmetry, and discrete time equations to compute the interval durations are described. An example is presented in which these methods are illustrated by applying them to a parallel-loaded resonant inverter with three equivalent circuits for its continuous mode of operation.

  4. Intentionally fabricated autobiographical memories.

    Science.gov (United States)

    Justice, Lucy V; Morrison, Catriona M; Conway, Martin A

    2018-02-01

    Participants generated both autobiographical memories (AMs) that they believed to be true and intentionally fabricated autobiographical memories (IFAMs). Memories were constructed while a concurrent memory load (random 8-digit sequence) was held in mind or while there was no concurrent load. Amount and accuracy of recall of the concurrent memory load was reliably poorer following generation of IFAMs than following generation of AMs. There was no reliable effect of load on memory generation times; however, IFAMs always took longer to construct than AMs. Finally, replicating previous findings, fewer IFAMs had a field perspective than AMs, IFAMs were less vivid than AMs, and IFAMs contained more motion words (indicative of increased cognitive load). Taken together, these findings show a pattern of systematic differences that mark out IFAMs, and they also show that IFAMs can be identified indirectly by lowered performance on concurrent tasks that increase cognitive load.

  5. NCSX Vacuum Vessel Fabrication

    International Nuclear Information System (INIS)

    Viola ME; Brown T; Heitzenroeder P; Malinowski F; Reiersen W; Sutton L; Goranson P; Nelson B; Cole M; Manuel M; McCorkle D.

    2005-01-01

    The National Compact Stellarator Experiment (NCSX) is being constructed at the Princeton Plasma Physics Laboratory (PPPL) in conjunction with the Oak Ridge National Laboratory (ORNL). The goal of this experiment is to develop a device which has the steady state properties of a traditional stellarator along with the high performance characteristics of a tokamak. A key element of this device is its highly shaped Inconel 625 vacuum vessel. This paper describes the manufacturing of the vessel. The vessel is being fabricated by Major Tool and Machine, Inc. (MTM) in three identical 120 o vessel segments, corresponding to the three NCSX field periods, in order to accommodate assembly of the device. The port extensions are welded on, leak checked, cut off within 1-inch of the vessel surface at MTM and then reattached at PPPL, to accommodate assembly of the close-fitting modular coils that surround the vessel. The 120 o vessel segments are formed by welding two 60 o segments together. Each 60 o segment is fabricated by welding ten press-formed panels together over a collapsible welding fixture which is needed to precisely position the panels. The vessel is joined at assembly by welding via custom machined 8-inch (20.3 cm) wide spacer ''spool pieces''. The vessel must have a total leak rate less than 5 X 10 -6 t-l/s, magnetic permeability less than 1.02(micro), and its contours must be within 0.188-inch (4.76 mm). It is scheduled for completion in January 2006

  6. Uncertainty in microscale gas damping: Implications on dynamics of capacitive MEMS switches

    International Nuclear Information System (INIS)

    Alexeenko, Alina; Chigullapalli, Sruti; Zeng Juan; Guo Xiaohui; Kovacs, Andrew; Peroulis, Dimitrios

    2011-01-01

    Effects of uncertainties in gas damping models, geometry and mechanical properties on the dynamics of micro-electro-mechanical systems (MEMS) capacitive switch are studied. A sample of typical capacitive switches has been fabricated and characterized at Purdue University. High-fidelity simulations of gas damping on planar microbeams are developed and verified under relevant conditions. This and other gas damping models are then applied to study the dynamics of a single closing event for switches with experimentally measured properties. It has been demonstrated that although all damping models considered predict similar damping quality factor and agree well for predictions of closing time, the models differ by a factor of two and more in predicting the impact velocity and acceleration at contact. Implications of parameter uncertainties on the key reliability-related parameters such as the pull-in voltage, closing time and impact velocity are discussed. A notable effect of uncertainty is that the nominal switch, i.e. the switch with the average properties, does not actuate at the mean actuation voltage. Additionally, the device-to-device variability leads to significant differences in dynamics. For example, the mean impact velocity for switches actuated under the 90%-actuation voltage (about 150 V), i.e. the voltage required to actuate 90% of the sample, is about 129 cm/s and increases to 173 cm/s for the 99%-actuation voltage (of about 173 V). Response surfaces of impact velocity and closing time to five input variables were constructed using the Smolyak sparse grid algorithm. The sensitivity analysis showed that impact velocity is most sensitive to the damping coefficient whereas the closing time is most affected by the geometric parameters such as gap and beam thickness. - Highlights: → We examine stochastic non-linear response of a microsystem switch subject to multiple input uncertainties. → Sample devices have been fabricated and device

  7. On The Snubber Influence To The Switching And Conduction Losses In A Converter Using Switched Capacitor

    Directory of Open Access Journals (Sweden)

    Viorel DUGAN

    2002-12-01

    Full Text Available The paper deals to design and to compute the snubber parameters influence on the switching and conduction losses of the transistors (IGBT used as bidirectional switches in a converter with switched capacitor. The converter was modelled with difference equations, and the transistors during turn-on and turn-off processes were simulated by dynamically varying resistance models. The energy loss per switching, commutation time, the variation of the transistor voltage etc. and the influence of snubber parameters in each of these cases are shown in the context of a converter used as a 50Hz reactive power controller unit

  8. Fabrication of superhydrophobic cotton fabrics using crosslinking polymerization method

    Science.gov (United States)

    Jiang, Bin; Chen, Zhenxing; Sun, Yongli; Yang, Huawei; Zhang, Hongjie; Dou, Haozhen; Zhang, Luhong

    2018-05-01

    With the aim of removing and recycling oil and organic solvent from water, a facile and low-cost crosslinking polymerization method was first applied on surface modification of cotton fabrics for water/oil separation. Micro-nano hierarchical rough structure was constructed by triethylenetetramine (TETA) and trimesoyl chloride (TMC) that formed a polymeric layer on the surface of the fabric and anchored Al2O3 nanoparticles firmly between the fabric surface and the polymer layer. Superhydrophobic property was further obtained through self-assembly grafting of hydrophobic groups on the rough surface. The as-prepared cotton fabric exhibited superoleophilicity in atmosphere and superhydrophobicity both in atmosphere and under oil with the water contact angle of 153° and 152° respectively. Water/oil separation test showed that the as-prepared cotton fabric can handle with various oil-water mixtures with a high separation efficiency over 99%. More importantly, the separation efficiency remained above 98% over 20 cycles of reusing without losing its superhydrophobicity which demonstrated excellent reusability in oil/water separation process. Moreover, the as-prepared cotton fabric possessed good contamination resistance ability and self-cleaning property. Simulation washing process test showed the superhydrophobic cotton fabric maintained high value of water contact angle above 150° after 100 times washing, indicating great stability and durability. In summary, this work provides a brand-new way to surface modification of cotton fabric and makes it a promising candidate material for oil/water separation.

  9. High-voltage high-current triggering vacuum switch

    International Nuclear Information System (INIS)

    Alferov, D.F.; Bunin, R.A.; Evsin, D.V.; Sidorov, V.A.

    2012-01-01

    Experimental investigations of switching and breaking capacities of the new high current triggered vacuum switch (TVS) are carried out at various parameters of discharge current. It has been shown that the high current triggered vacuum switch TVS can switch repeatedly a current from units up to ten kiloampers with duration up to ten millisecond [ru

  10. A new Zero-Voltage-Transition PWM switching cell

    Energy Technology Data Exchange (ETDEWEB)

    Grigore, V. [Electronics and Telecommunications Faculty `Politebuica` University Bucharest (Romania); Kyyrae, J. [Helsinki University of Technology, Otaniemi (Finland): Institute of Intelligent Power Electronics

    1997-12-31

    In this paper a new Zero-Voltage-Transition (ZVT) PWM switching cell is presented. The proposed switching cell is composed of the normal hard-switched PWM cell (consisting of one active switch and one passive switch), plus an auxiliary circuit (consisting of one active switch and some reactive components). The auxiliary circuit is inactive during the ON and OFF intervals of the switches in the normal PWM switch. However, the transitions between the two states are controlled by the auxiliary circuit. Prior to turn-on, the voltage across the active switch in the PWM cell is forced to zero, thus the turn-on losses of the active switch are practically eliminated. At turn-off the auxiliary circuit behaves like a non-dissipative passive snubber reducing the turn-off losses to a great extent. Zero-Voltage-Transition switching technique almost eliminates switching losses. The active switch operates under ZVT conditions, the passive switch (diode) has a controlled reverse recovery, and the switch in the auxiliary circuit operates under Zero-Current-Switching (ZCS) conditions. (orig.) 6 refs.

  11. A high-switching-frequency flyback converter in resonant mode

    NARCIS (Netherlands)

    Li, Jianting; van Horck, Frank B.M.; Daniel, Bobby J.; Bergveld, Henk Jan

    2017-01-01

    The demand of miniaturization of power systems has accelerated the research on high-switching-frequency power converters. A flyback converter in resonant mode that features low switching losses, less transformer losses, and low switching noise at high switching frequency is investigated in this

  12. PZT Films Fabricated by Metal Organic Decomposition Method

    Science.gov (United States)

    Sobolev, Vladimir; Ishchuk, Valeriy

    2014-03-01

    High quality lead zirconate titanate films have been fabricated on different substrates by metal organic decomposition method and their ferroelectric properties have been investigated. Main attention was paid to studies of the influence of the buffer layer with conditional composition Pb1.3(Zr0.5Ti0.5) O3 on the properties of Pb(Zr0.5Ti0.5) O3 films fabricated on the polycrystalline titanium and platinum substrates. It is found that in the films on the Pt substrate (with or without the buffer layer) the dependencies of the remanent polarization and the coercivity field on the number of switching cycles do not manifest fatigue up to 109 cycles. The remanent polarization dependencies for films on the Ti substrate with the buffer layer containing an excess of PbO demonstrate an fundamentally new feature that consists of a remanent polarization increase after 108 switching cycles. The increase of remanent polarization is about 50% when the number of cycles approaches 1010, while the increase of the coercivity field is small. A monotonic increase of dielectric losses has been observed in all cases.

  13. 6.1-MV, 0.79-MA laser-triggered gas switch for multimodule, multiterawatt pulsed-power accelerators

    Directory of Open Access Journals (Sweden)

    K. R. LeChien

    2010-03-01

    Full Text Available A 6.1-MV, 0.79-MA laser-triggered gas switch (LTGS is used to synchronize the 36 modules of the Z machine at Sandia National Laboratories. Each module includes one switch, which serves as the last command-fired switch of the module, and hence is used to determine the time at which each module electrically closes relative to the other modules. The switch is ∼81-cm in length, ∼45-cm in diameter, and is immersed in mineral oil. The outer switch envelope consists of six corrugated monomer-cast acrylic insulators and five contoured stainless-steel rings. The trigger electrodes are fabricated from copper-infused tungsten. The switch is pressurized with several atmospheres of sulfur hexafluoride (SF_{6}, which is turbulently purged within 2 seconds after every shot. Each switch is powered from a 6-MV, 0.78-MJ Marx generator which pulse charges a 24-nF intermediate-store water capacitor in 1.4-μs. Closure of the switch allows power to flow into pulse-forming transmission lines. The power pulse is subsequently compressed by water switches, which results in a total accelerator output power in excess of 70-TW. A previous version of the LTGS performed exceptionally at a 5.4-MV, 0.7-MA level on an engineering test module used for switch development. It exhibited a 1-σ jitter of ∼5  ns, a prefire and flashover rate less than 0.1%, and a lifetime in excess of 150 shots. When installed on the Z accelerator, however, the switch exhibited a prefire probability of ∼3%, a flashover probability of ∼7%, and a 15-ns jitter. The difference in performance is attributed to several factors such as higher total charge transfer, exposure to more debris, and more stressful dynamic mechanical loading upon machine discharge. Under these conditions, the replacement lifetime was less than ten shots. Since refurbishment of Z in October 2007, there have been three LTGS design iterations to improve the performance at 6.1-MV. The most recent design exhibits a

  14. Large Area Silicon Carbide Vertical JFETs for 1200 V Cascode Switch Operation

    Directory of Open Access Journals (Sweden)

    Victor Veliadis

    2008-01-01

    Full Text Available SiC VJFETs are excellent candidates for reliable high-power/temperature switching as they only use pn junctions in the active device area where the high-electric fields occur. VJFETs do not suffer from forward voltage degradation, exhibit excellent short-circuit performance, and operate at 300°C. 0.19 cm2 1200 V normally-on and 0.15 cm2 low-voltage normally-off VJFETs were fabricated. The 1200-V VJFET outputs 53 A with a forward drain voltage drop of 2 V and a specific onstate resistance of 5.4 mΩ cm2. The low-voltage VJFET outputs 28 A with a forward drain voltage drop of 3.3 V and a specific onstate resistance of 15 mΩ cm2. The 1200-V SiC VJFET was connected in the cascode configuration with two Si MOSFETs and with a low-voltage SiC VJFET to form normally-off power switches. At a forward drain voltage drop of 2.2 V, the SiC/MOSFETs cascode switch outputs 33 A. The all-SiC cascode switch outputs 24 A at a voltage drop of 4.7 V.

  15. Electronic bipolar resistive switching behavior in Ni/VOx/Al device

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Mengseng [School of Electronic Information Engineering, Hebei University of Technology, Tianjin Key Laboratory of Electronic Materials and Devices, Tianjin 300130 (China); School of Electronic Information Engineering, Tianjin Key Laboratory of Film Electronic & Communication Devices, Tianjin University of Technology, Tianjin 300384 (China); Zhang, Kailiang, E-mail: kailiang_zhang@163.com [School of Electronic Information Engineering, Tianjin Key Laboratory of Film Electronic & Communication Devices, Tianjin University of Technology, Tianjin 300384 (China); Yang, Ruixia, E-mail: yangrx@hebut.edu.cn [School of Electronic Information Engineering, Hebei University of Technology, Tianjin Key Laboratory of Electronic Materials and Devices, Tianjin 300130 (China); Wang, Fang; Zhang, Zhichao; Wu, Shijian [School of Electronic Information Engineering, Tianjin Key Laboratory of Film Electronic & Communication Devices, Tianjin University of Technology, Tianjin 300384 (China)

    2017-07-15

    Highlights: • The resistive random access memory of Ni/VOx/Al was fabricated. • The device has the electronic bipolar resistive switching characteristic. • The activity energy (Ea) of HRS has been calculated. • The reasons of the degradation of the resistance ratio of HRS/LRS were analyzed. - Abstract: In this paper, the Ni/VOx/Al resistive random access memory (RRAM) device is constructed and it shows bipolar resistive switching behavior, low resistive state (LRS) nonlinearity, and good retention. The set and reset processes are likely induced by the electron trapping and detrapping of trapping centers in the VOx films, respectively. The conduction mechanism in negative/positive region are controlled by space charge limited current mechanism (SCLC)/Schottky emission. The temperature dependence of I–V curves for HRS is measured to confirm the defects trapping and detrapping electrons model. activation energy was calculated to analyze the endurance performance of the device. The detailed analysis of the switching behavior with SCLC mechanism and Schottky emission mechanism could provide useful information for electronic bipolar resistive switching (eBRS) characteristics.

  16. Electronic bipolar resistive switching behavior in Ni/VOx/Al device

    International Nuclear Information System (INIS)

    Xia, Mengseng; Zhang, Kailiang; Yang, Ruixia; Wang, Fang; Zhang, Zhichao; Wu, Shijian

    2017-01-01

    Highlights: • The resistive random access memory of Ni/VOx/Al was fabricated. • The device has the electronic bipolar resistive switching characteristic. • The activity energy (Ea) of HRS has been calculated. • The reasons of the degradation of the resistance ratio of HRS/LRS were analyzed. - Abstract: In this paper, the Ni/VOx/Al resistive random access memory (RRAM) device is constructed and it shows bipolar resistive switching behavior, low resistive state (LRS) nonlinearity, and good retention. The set and reset processes are likely induced by the electron trapping and detrapping of trapping centers in the VOx films, respectively. The conduction mechanism in negative/positive region are controlled by space charge limited current mechanism (SCLC)/Schottky emission. The temperature dependence of I–V curves for HRS is measured to confirm the defects trapping and detrapping electrons model. activation energy was calculated to analyze the endurance performance of the device. The detailed analysis of the switching behavior with SCLC mechanism and Schottky emission mechanism could provide useful information for electronic bipolar resistive switching (eBRS) characteristics.

  17. CONTROL OF BOUNCING IN RF MEMS SWITCHES USING DOUBLE ELECTRODE

    KAUST Repository

    Abdul Rahim, Farhan

    2014-05-01

    MEMS based mechanical switches are seen to be the likely replacements for CMOS based switches due to the several advantages that these mechanical switches have over CMOS switches. Mechanical switches can be used in systems under extreme conditions and also provide more reliability and cause less power loss. A major problem with mechanical switches is bouncing. Bouncing is an undesirable characteristic which increases the switching time and causes damage to the switch structure affecting the overall switch life. This thesis proposes a new switch design that may be used to mitigate bouncing by using two voltage sources using a double electrode configuration. The effect of many switch’s tunable parameters is also discussed and an effective tuning technique is also provided. The results are compared to the current control schemes in literature and show that the double electrode scheme is a viable control option.

  18. High optical and switching performance electrochromic devices based on a zinc oxide nanowire with poly(methyl methacrylate) gel electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Young Tea; Chu, Daping, E-mail: dpc31@cam.ac.uk [Electrical Engineering Division, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA (United Kingdom); Neeves, Matthew; Placido, Frank [Thin Film Centre, University of the West of Scotland, Paisley PA1 2BE (United Kingdom); Smithwick, Quinn [Disney Research, 521 Circle Seven Drive, Glendale, Los Angeles, California 91201 (United States)

    2014-11-10

    High performance electrochromic devices have been fabricated and demonstrated utilizing a solid polymer electrolyte and zinc oxide (ZnO) nanowire (NW) array counter electrode. The poly(methyl methacrylate) based polymer electrolyte was spin coated upon hydrothermally grown ZnO NW array counter electrodes, while electron beam evaporated NiO{sub x} thin films formed the working electrodes. Excellent optical contrast and switching speeds were observed in the fabricated devices with active areas of 2 cm{sup 2}, exhibiting an optical contrast of 73.11% at the wavelength of 470 nm, combined with a fast switching time of 0.2 s and 0.4 s for bleaching and coloration, respectively.

  19. High optical and switching performance electrochromic devices based on a zinc oxide nanowire with poly(methyl methacrylate) gel electrolytes

    International Nuclear Information System (INIS)

    Chun, Young Tea; Chu, Daping; Neeves, Matthew; Placido, Frank; Smithwick, Quinn

    2014-01-01

    High performance electrochromic devices have been fabricated and demonstrated utilizing a solid polymer electrolyte and zinc oxide (ZnO) nanowire (NW) array counter electrode. The poly(methyl methacrylate) based polymer electrolyte was spin coated upon hydrothermally grown ZnO NW array counter electrodes, while electron beam evaporated NiO x thin films formed the working electrodes. Excellent optical contrast and switching speeds were observed in the fabricated devices with active areas of 2 cm 2 , exhibiting an optical contrast of 73.11% at the wavelength of 470 nm, combined with a fast switching time of 0.2 s and 0.4 s for bleaching and coloration, respectively

  20. Process for fabrication of cermets

    Science.gov (United States)

    Landingham, Richard L [Livermore, CA

    2011-02-01

    Cermet comprising ceramic and metal components and a molten metal infiltration method and process for fabrication thereof. The light weight cermets having improved porosity, strength, durability, toughness, elasticity fabricated from presintered ceramic powder infiltrated with a molten metal or metal alloy. Alumina titanium cermets biocompatible with the human body suitable for bone and joint replacements.

  1. CW RFQ fabrication and engineering

    International Nuclear Information System (INIS)

    Schrage, D.; Young, L.; Roybal, P.

    1998-01-01

    The design and fabrication of a four-vane RFQ to deliver a 100 mA CW proton beam at 6.7 MeV is described. This linac is an Oxygen-Free Electrolytic (OFE) copper structure 8 m in length and was fabricated using hydrogen furnace brazing as the joining technology

  2. Bipolar resistive switching in graphene oxide based metal insulator metal structure for non-volatile memory applications

    Science.gov (United States)

    Singh, Rakesh; Kumar, Ravi; Kumar, Anil; Kashyap, Rajesh; Kumar, Mukesh; Kumar, Dinesh

    2018-05-01

    Graphene oxide based devices have attracted much attention recently because of their possible application in next generation electronic devices. In this study, bipolar resistive switching characteristics of graphene oxide based metal insulator metal structure were investigated for nonvolatile memories. The graphene oxide was prepared by the conventional Hummer's method and deposited on ITO coated glass by spin-coating technique. The dominant mechanism of resistive switching is the formation and rupture of the conductive filament inside the graphene oxide. The conduction mechanism for low and high resistance states are dominated by two mechanism the ohmic conduction and space charge limited current (SCLC) mechanism, respectively. Atomic Force Microscopy, X-ray diffraction, Cyclic-Voltammetry were conducted to observe the morphology, structure and behavior of the material. The fabricated device with Al/GO/ITO structure exhibited reliable bipolar resistive switching with set & reset voltage of -2.3 V and 3V respectively.

  3. Laterally configured resistive switching device based on transition-metal nano-gap electrode on Gd oxide

    Energy Technology Data Exchange (ETDEWEB)

    Kawakita, Masatoshi; Okabe, Kyota [Department of Physics, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581 (Japan); Kimura, Takashi [Department of Physics, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581 (Japan); Research Center for Quantum Nano-Spin Sciences, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581 (Japan)

    2016-01-11

    We have developed a fabrication process for a laterally configured resistive switching device based on a Gd oxide. A nano-gap electrode connected by a Gd oxide with the ideal interfaces has been created by adapting the electro-migration method in a metal/GdO{sub x} bilayer system. Bipolar set and reset operations have been clearly observed in the Pt/GdO{sub x} system similarly in the vertical device based on GdO{sub x}. Interestingly, we were able to observe a clear bipolar switching also in a ferromagnetic CoFeB nano-gap electrode with better stability compared to the Pt/GdO{sub x} device. The superior performance of the CoFeB/GdO{sub x} device implies the importance of the spin on the resistive switching.

  4. Broadband nonvolatile photonic switching based on optical phase change materials: beyond the classical figure-of-merit.

    Science.gov (United States)

    Zhang, Qihang; Zhang, Yifei; Li, Junying; Soref, Richard; Gu, Tian; Hu, Juejun

    2018-01-01

    In this Letter, we propose a broadband, nonvolatile on-chip switch design in the telecommunication C-band with record low loss and crosstalk. The unprecedented device performance builds on: 1) a new optical phase change material (O-PCM) Ge 2 Sb 2 Se 4 Te 1 (GSST), which exhibits significantly reduced optical attenuation compared to traditional O-PCMs, and 2) a nonperturbative design that enables low-loss device operation beyond the classical figure-of-merit (FOM) limit. We further demonstrate that the 1-by-2 and 2-by-2 switches can serve as basic building blocks to construct nonblocking and nonvolatile on-chip switching fabric supporting arbitrary numbers of input and output ports.

  5. Analog memory and spike-timing-dependent plasticity characteristics of a nanoscale titanium oxide bilayer resistive switching device

    International Nuclear Information System (INIS)

    Seo, Kyungah; Park, Sangsu; Lee, Kwanghee; Lee, Byounghun; Hwang, Hyunsang; Kim, Insung; Jung, Seungjae; Jo, Minseok; Park, Jubong; Shin, Jungho; Biju, Kuyyadi P; Kong, Jaemin

    2011-01-01

    We demonstrated analog memory, synaptic plasticity, and a spike-timing-dependent plasticity (STDP) function with a nanoscale titanium oxide bilayer resistive switching device with a simple fabrication process and good yield uniformity. We confirmed the multilevel conductance and analog memory characteristics as well as the uniformity and separated states for the accuracy of conductance change. Finally, STDP and a biological triple model were analyzed to demonstrate the potential of titanium oxide bilayer resistive switching device as synapses in neuromorphic devices. By developing a simple resistive switching device that can emulate a synaptic function, the unique characteristics of synapses in the brain, e.g. combined memory and computing in one synapse and adaptation to the outside environment, were successfully demonstrated in a solid state device.

  6. Fault Tolerant Operation of ISOP Multicell Dc-Dc Converter Using Active Gate Controlled SiC Protection Switch

    Directory of Open Access Journals (Sweden)

    Yusuke Hayashi

    2016-01-01

    Full Text Available An active gate controlled semiconductor protection switch using SiC-MOSFET is proposed to achieve the fault tolerant operation of ISOP (Input Series and Output Parallel connected multicell dc-dc converter. The SiC-MOSFET with high temperature capability simplifies the configuration of the protection circuit, and its on-resistance control by the active gate controller realizes the smooth protection without the voltage and the current surges. The first laboratory prototype of the protection switch is fabricated by using a SiC-MOSFET with a high frequency buck chopper for the active gate controller. The effectiveness of the proposed protection switch is verified, taking the impact of the volume reduction into account.

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

    Science.gov (United States)

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

    2018-06-01

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

  8. CMOS-NEMS Copper Switches Monolithically Integrated Using a 65 nm CMOS Technology

    Directory of Open Access Journals (Sweden)

    Jose Luis Muñoz-Gamarra

    2016-02-01

    Full Text Available This work demonstrates the feasibility to obtain copper nanoelectromechanical (NEMS relays using a commercial complementary metal oxide semiconductor (CMOS technology (ST 65 nm following an intra CMOS-MEMS approach. We report experimental demonstration of contact-mode nano-electromechanical switches obtaining low operating voltage (5.5 V, good ION/IOFF (103 ratio, abrupt subthreshold swing (4.3 mV/decade and minimum dimensions (3.50 μm × 100 nm × 180 nm, and gap of 100 nm. With these dimensions, the operable Cell area of the switch will be 3.5 μm (length × 0.2 μm (100 nm width + 100 nm gap = 0.7 μm2 which is the smallest reported one using a top-down fabrication approach.

  9. A complementary switching mechanism for organic memory devices to regulate the conductance of binary states

    Science.gov (United States)

    Vyas, Giriraj; Dagar, Parveen; Sahu, Satyajit

    2016-06-01

    We have fabricated an organic non-volatile memory device wherein the ON/OFF current ratio has been controlled by varying the concentration of a small organic molecule, 2,3-Dichloro-5,6-dicyano-p-benzoquinone (DDQ), in an insulating matrix of a polymer Poly(4-vinylphenol) (PVP). A maximum ON-OFF ratio of 106 is obtained when the concentration of DDQ is half or 10 wt. % of PVP. In this process, the switching direction for the devices has also been altered, indicating the disparity in conduction mechanism. Conduction due to metal filament formation through the active material and the voltage dependent conformational change of the organic molecule seem to be the motivation behind the gradual change in the switching direction.

  10. Black phosphorus saturable absorber for Q-switched Er:YAG laser at 1645 nm

    Science.gov (United States)

    Guo, Lei; Li, Tao; Zhang, Shuaiyi; Wang, Mingjian; Yang, Kejian; Fan, Mingqi; Zhao, Shengzhi; Li, Ming

    2018-03-01

    A Q-switched Er:YAG solid-state laser at 1645 nm based on black phosphorus (BP) saturable absorbers (SAs) was demonstrated firstly to our knowledge. The BP-SA was fabricated by drop-casting BP nanoplatelets dispersion on a YAG substrate and corresponding saturable absorption properties were characterized at 1.6 μm. By employing as-prepared BP-SAs, stable Q-switched laser operations were achieved with a pulse width of 2.8 μs and a repetition rate of 34 kHz, corresponding to the average output power of 0.33 W. The results verify that BP-SAs have great potential for pulsed 1.6 μm lasers.

  11. A new coupling mechanism between two graphene electron waveguides for ultrafast switching

    Science.gov (United States)

    Huang, Wei; Liang, Shi-Jun; Kyoseva, Elica; Ang, Lay Kee

    2018-03-01

    In this paper, we report a novel coupling between two graphene electron waveguides, in analogy the optical waveguides. The design is based on the coherent quantum mechanical tunneling of Rabi oscillation between the two graphene electron waveguides. Based on this coupling mechanism, we propose that it can be used as an ultrafast electronic switching device. Based on a modified coupled mode theory, we construct a theoretical model to analyze the device characteristics, and predict that the switching speed is faster than 1 ps and the on-off ratio exceeds 106. Due to the long mean free path of electrons in graphene at room temperature, the proposed design avoids the limitation of low temperature operation required in the traditional design by using semiconductor quantum-well structure. The layout of our design is similar to that of a standard complementary metal-oxide-semiconductor transistor that should be readily fabricated with current state-of-art nanotechnology.

  12. Resistive switching and voltage induced modulation of tunneling magnetoresistance in nanosized perpendicular organic spin valves

    Directory of Open Access Journals (Sweden)

    Robert Göckeritz

    2016-04-01

    Full Text Available Nanoscale multifunctional perpendicular organic spin valves have been fabricated. The devices based on an La0.7Sr0.3MnO3/Alq3/Co trilayer show resistive switching of up to 4-5 orders of magnitude and magnetoresistance as high as -70% the latter even changing sign when voltage pulses are applied. This combination of phenomena is typically observed in multiferroic tunnel junctions where it is attributed to magnetoelectric coupling between a ferromagnet and a ferroelectric material. Modeling indicates that here the switching originates from a modification of the La0.7Sr0.3MnO3 surface. This modification influences the tunneling of charge carriers and thus both the electrical resistance and the tunneling magnetoresistance which occurs at pinholes in the organic layer.

  13. PCBM : P3HT polymer composites for photonic crystal all-optical switching applications

    International Nuclear Information System (INIS)

    Li Zhiqiang; Hu Xiaoyong; Zhang Jiaxiang; Yang Hong; Gong Qihuang

    2010-01-01

    An all-optical switching with an operating pump intensity of 1 MW cm -2 is realized in a one-dimensional nonlinear organic photonic crystal made of poly(3-hexylthiophene) doped with 1-(3-methoxycarbonyl)propyl-1-phenyl-(6,6)C 61 , fabricated by focused ion-beam etching. The femtosecond pump and probe method is adopted to measure the transmittance changes of the probe laser based on the photonic bandgap shift induced by the pump laser. Under resonant excitation, a large nonlinear refractive index of the order of 10 -9 cm 2 W -1 is obtained for the polymer composite. A switching time of 58.9 ps is maintained due to intermolecular charge transfer and exciton-exciton annihilation.

  14. PCBM : P3HT polymer composites for photonic crystal all-optical switching applications

    Energy Technology Data Exchange (ETDEWEB)

    Li Zhiqiang; Hu Xiaoyong; Zhang Jiaxiang; Yang Hong; Gong Qihuang, E-mail: xiaoyonghu@pku.edu.c, E-mail: qhgong@pku.edu.c [State Key Laboratory for Mesoscopic Physics and Department of Physics, Peking University, Beijing 100871 (China)

    2010-09-29

    An all-optical switching with an operating pump intensity of 1 MW cm{sup -2} is realized in a one-dimensional nonlinear organic photonic crystal made of poly(3-hexylthiophene) doped with 1-(3-methoxycarbonyl)propyl-1-phenyl-(6,6)C{sub 61}, fabricated by focused ion-beam etching. The femtosecond pump and probe method is adopted to measure the transmittance changes of the probe laser based on the photonic bandgap shift induced by the pump laser. Under resonant excitation, a large nonlinear refractive index of the order of 10{sup -9} cm{sup 2} W{sup -1} is obtained for the polymer composite. A switching time of 58.9 ps is maintained due to intermolecular charge transfer and exciton-exciton annihilation.

  15. EXPERIMENTATION OF THREE PHASE OUTER ROTATING SWITCHED RELUCTANCE MOTOR WITH SOFT MAGNETIC COMPOSITE MATERIALS

    Directory of Open Access Journals (Sweden)

    N. C. LENIN

    2017-01-01

    Full Text Available This paper presents the application of Soft Magnetic Composite (SMC material in Outer Rotating Switched Reluctance Motor (ORSRM. The presented stator core of the Switched Reluctance Motor was made of two types of material, the classical laminated silicon steel sheet and the soft magnetic composite material. First, the stator core made of laminated steel has been analysed. The next step is to analyse the identical geometry SRM with the soft magnetic composite material, SOMALOY for its stator core. The comparisons of both cores include the calculated torque and torque ripple, magnetic conditions, simplicity of fabrication and cost. The finite element method has been used to analyse the magnetic conditions and the calculated torque. Finally, tested results shows that SMC is a better choice for SRM in terms of torque ripple and power density.

  16. Schottky barrier diode embedded AlGaN/GaN switching transistor

    International Nuclear Information System (INIS)

    Park, Bong-Ryeol; Lee, Jung-Yeon; Lee, Jae-Gil; Lee, Dong-Myung; Cha, Ho-Young; Kim, Moon-Kyung

    2013-01-01

    We developed a Schottky barrier diode (SBD) embedded AlGaN/GaN switching transistor to allow negative current flow during off-state condition. An SBD was embedded in a recessed normally-off AlGaN/GaN-on-Si metal-oxide-semiconductor heterostructure field-effect transistor (MOSHFET). The fabricated device exhibited normally-off characteristics with a gate threshold voltage of 2.8 V, a diode turn-on voltage of 1.2 V, and a breakdown voltage of 849 V for the anode-to-drain distance of 8 µm. An on-resistance of 2.66 mΩcm 2 was achieved at a gate voltage of 16 V in the forward transistor mode. Eliminating the need for an external diode, the SBD embedded switching transistor has advantages of significant reduction in parasitic inductance and chip area. (paper)

  17. The Transistor as Low Level Switch

    Energy Technology Data Exchange (ETDEWEB)

    Lyden, Anders

    1963-10-15

    The common collector transistor switch has in the on state with open emitter a certain offset voltage U{sub EK} {approx_equal} -kT/qB{sub N}. This expression is derived in a new, more physical way. It is further shown at which emitter current the current amplification factor B{sub N} should be measured to get a correct value for the above expression. The collector current I at zero collector voltage I{sub K} = I{sub 0}(exp(qU{sub E}/kT) - 1) extremely well. Substitution of I{sub EBO} and I{sub KBO} by I{sub 0} in Eber's and Moll's relations consequently improves these equations and the characteristics of the transistor switch can be better determined. At switching on and off transients appear across the switch. The influence of the 'spike' at switching off can be described by an current I{sub SPIKE} which is easy to calculate. I{sub SPIKE} is approximately dependent only on the base - emitter depletion layer capacitance and the chopper frequency f{sub 0}. Some compensated switches have lower drift than the drift in U{sub EK}. They may, for example, have a temperature drift < 0.2 {mu}V/deg C and a long time drift < 2 {mu}V/week. Some compensated switches also have I{sub SPIKE} < 10{sup -12} f{sub 0}A. The static offset current in the off state can easily be made < 10{sup -12} A.

  18. DRAPING SIMULATION OF WOVEN FABRICS

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, William [General Motors LLC; Jin, Xiaoshi [ESI Group NA; Zhu, Jiang [Optimal CAE; Wathen, Terrence [General Motors LLC; Doroudian2, Mark [ESI Group NA; Aitharaju, Venkat [General Motors LLC

    2016-09-07

    Woven fabric composites are extensively used in molding complex geometrical shapes due to their high conformability compared to other fabrics. Preforming is an important step in the overall process, where the two-dimensional fabric is draped to become the three-dimensional shape of the part prior to resin injection. During preforming, the orientation of the yarns may change significantly compared to the initial orientations. Accurate prediction of the yarn orientations after molding is important for evaluating the structural performance of the final part. This paper presents a systematic investigation of the angle changes during the preform operation for carbon fiber twill and satin weave fabrics. Preforming experiments were conducted using a truncated pyramid mold geometry designed and fabricated at the General Motors Research Laboratories. Predicted results for the yarn orientations were compared with experimental results and good agreement was observed

  19. Nuclear fuel fabrication - developing indigenous capability

    International Nuclear Information System (INIS)

    Gupta, U.C.; Jayaraj, R.N.; Meena, R.; Sastry, V.S.; Radhakrishna, C.; Rao, S.M.; Sinha, K.K.

    1997-01-01

    Nuclear Fuel Complex (NFC), established in early 70's for production of fuel for PHWRs and BWRs in India, has made several improvements in different areas of fuel manufacturing. Starting with wire-wrap type of fuel bundles, NFC had switched over to split spacer type fuel bundle production in mid 80's. On the upstream side slurry extraction was introduced to prepare the pure uranyl nitrate solution directly from the MDU cake. Applying a thin layer of graphite to the inside of the tube was another modification. The Complex has developed cost effective and innovative techniques for these processes, especially for resistance welding of appendages on the fuel elements which has been a unique feature of the Indian PHWR fuel assemblies. Initially, the fuel fabrication plants were set-up with imported process equipment for most of the pelletisation and assembly operations. Gradually with design and development of indigenous equipment both for production and quality control, NFC has demonstrated total self reliance in fuel production by getting these special purpose machines manufactured indigenously. With the expertise gained in different areas of process development and equipment manufacturing, today NFC is in a position to offer know-how and process equipment at very attractive prices. The paper discusses some of the new processes that are developed/introduced in this field and describes different features of a few PLC based automatic equipment developed. Salient features of innovative techniques being adopted in the area Of UO 2 powder production are also briefly indicated. (author)

  20. Optimization of multi-branch switched diversity systems

    KAUST Repository

    Nam, Haewoon

    2009-10-01

    A performance optimization based on the optimal switching threshold(s) for a multi-branch switched diversity system is discussed in this paper. For the conventional multi-branch switched diversity system with a single switching threshold, the optimal switching threshold is a function of both the average channel SNR and the number of diversity branches, where computing the optimal switching threshold is not a simple task when the number of diversity branches is high. The newly proposed multi-branch switched diversity system is based on a sequence of switching thresholds, instead of a single switching threshold, where a different diversity branch uses a different switching threshold for signal comparison. Thanks to the fact that each switching threshold in the sequence can be optimized only based on the number of the remaining diversity branches, the proposed system makes it easy to find these switching thresholds. Furthermore, some selected numerical and simulation results show that the proposed switched diversity system with the sequence of optimal switching thresholds outperforms the conventional system with the single optimal switching threshold. © 2009 IEEE.

  1. Analytical Modeling and Simulation of Four-Switch Hybrid Power Filter Working with Sixfold Switching Symmetry

    Czech Academy of Sciences Publication Activity Database

    Tlustý, J.; Škramlík, Jiří; Švec, J.; Valouch, Viktor

    2012-01-01

    Roč. 2012, č. 292178 (2012), s. 1-17 ISSN 1024-123X Institutional support: RVO:61388998 Keywords : analytical modeling * four-switch hybrid power filter * sixfold switching symmetry Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.383, year: 2012 http://www.hindawi.com/journals/mpe/2012/292178/

  2. Analysis on the Motivations of Code–Switching%Analysis on the Motivations of Code– Switching

    Institute of Scientific and Technical Information of China (English)

    孔祥曼

    2015-01-01

    Code-switching is a common phenomenon in language contact. It reflects the speaker's psychological state and his attitude towards a certain language or a language variety. This paper briefly analyzes the social and psychological motivations of the speakers when they use code-switching.

  3. Generalized Multi-Cell Switched-Inductor and Switched-Capacitor Z-source Inverters

    DEFF Research Database (Denmark)

    Li, Ding; Chiang Loh, Poh; Zhu, Miao

    2013-01-01

    . Their boosting gains are, therefore, limited in practice. To overcome these shortcomings, the generalized switched-inductor and switched-capacitor Z-source inverters are proposed, whose extra boosting abilities and other advantages have already been verified in simulation and experiment....

  4. GaN transistors on Si for switching and high-frequency applications

    Science.gov (United States)

    Ueda, Tetsuzo; Ishida, Masahiro; Tanaka, Tsuyoshi; Ueda, Daisuke

    2014-10-01

    In this paper, recent advances of GaN transistors on Si for switching and high-frequency applications are reviewed. Novel epitaxial structures including superlattice interlayers grown by metal organic chemical vapor deposition (MOCVD) relieve the strain and eliminate the cracks in the GaN over large-diameter Si substrates up to 8 in. As a new device structure for high-power switching application, Gate Injection Transistors (GITs) with a p-AlGaN gate over an AlGaN/GaN heterostructure successfully achieve normally-off operations maintaining high drain currents and low on-state resistances. Note that the GITs on Si are free from current collapse up to 600 V, by which the drain current would be markedly reduced after the application of high drain voltages. Highly efficient operations of an inverter and DC-DC converters are presented as promising applications of GITs for power switching. The high efficiencies in an inverter, a resonant LLC converter, and a point-of-load (POL) converter demonstrate the superior potential of the GaN transistors on Si. As for high-frequency transistors, AlGaN/GaN heterojuction field-effect transistors (HFETs) on Si designed specifically for microwave and millimeter-wave frequencies demonstrate a sufficiently high output power at these frequencies. Output powers of 203 W at 2.5 GHz and 10.7 W at 26.5 GHz are achieved by the fabricated GaN transistors. These devices for switching and high-frequency applications are very promising as future energy-efficient electronics because of their inherent low fabrication cost and superior device performance.

  5. Switch on the competition. Causes, consequences and policy implications of consumer switching costs

    International Nuclear Information System (INIS)

    Pomp, M.; Shestalova, V.; Rangel, L.

    2005-09-01

    The success or failure of reforms aimed at liberalising markets depends to an important degree on consumer behaviour. If consumers do not base their choices on differences in prices and quality, competition between firms may be weak and the benefits of liberalisation to consumers may be small. One possible reason why consumers may respond only weakly to differences in price and quality is high costs of switching to another firm. This report presents a framework for analysing markets with switching costs and applies the framework in two empirical case studies. The first case study analyses the residential energy market, the second focuses on the market for social health insurance. In both markets, there are indications that switching costs are substantial. The report discusses policy options for reducing switching costs and for alleviating the consequences of switching costs

  6. Parasitic resistive switching uncovered from complementary resistive switching in single active-layer oxide memory device

    Science.gov (United States)

    Zhu, Lisha; Hu, Wei; Gao, Chao; Guo, Yongcai

    2017-12-01

    This paper reports the reversible transition processes between the bipolar and complementary resistive switching (CRS) characteristics on the binary metal-oxide resistive memory devices of Pt/HfO x /TiN and Pt/TaO x /TiN by applying the appropriate bias voltages. More interestingly, by controlling the amplitude of the negative bias, the parasitic resistive switching effect exhibiting repeatable switching behavior is uncovered from the CRS behavior. The electrical observation of the parasitic resistive switching effect can be explained by the controlled size of the conductive filament. This work confirms the transformation and interrelationship among the bipolar, parasitic, and CRS effects, and thus provides new insight into the understanding of the physical mechanism of the binary metal-oxide resistive switching memory devices.

  7. Switch on the competition. Causes, consequences and policy implications of consumer switching costs

    Energy Technology Data Exchange (ETDEWEB)

    Pomp, M.; Shestalova, V.; Rangel, L.

    2005-09-15

    The success or failure of reforms aimed at liberalising markets depends to an important degree on consumer behaviour. If consumers do not base their choices on differences in prices and quality, competition between firms may be weak and the benefits of liberalisation to consumers may be small. One possible reason why consumers may respond only weakly to differences in price and quality is high costs of switching to another firm. This report presents a framework for analysing markets with switching costs and applies the framework in two empirical case studies. The first case study analyses the residential energy market, the second focuses on the market for social health insurance. In both markets, there are indications that switching costs are substantial. The report discusses policy options for reducing switching costs and for alleviating the consequences of switching costs.

  8. Secure Automated Fabrication: an overview of remote breeder fuel fabrication

    International Nuclear Information System (INIS)

    Nyman, D.H.; Graham, R.A.

    1983-10-01

    The Secure Automated Fabrication (SAF) line is an automated, remotely controlled breeder fuel pin fabrication process which is to be installed in the Fuels and Materials Examination Facility (FMEF). The FMEF is presently under construction at Hanford and is scheduled for completion in 1984. The SAF line is scheduled for startup in 1987 and will produce mixed uranium-plutonium fuel pins for the Fast Flux Test Facility (FFTF) and the Clinch River Breeder Reactor Plant (CRBRP). The fabrication line and support systems are described

  9. Low threshold all-optical crossbar switch on GaAs-GaAlAs channel waveguide arrays

    Science.gov (United States)

    Jannson, Tomasz; Kostrzewski, Andrew

    1994-09-01

    During the Phase 2 project entitled 'Low Threshold All-Optical Crossbar Switch on GaAs - GaAlAs Channel Waveguide Array,' Physical Optics Corporation (POC) developed the basic principles for the fabrication of all-optical crossbar switches. Based on this development. POC fabricated a 2 x 2 GaAs/GaAlAs switch that changes the direction of incident light with minimum insertion loss and nonlinear distortion. This unique technology can be used in both analog and digital networks. The applications of this technology are widespread. Because the all-optical network does not have any speed limitations (RC time constant), POC's approach will be beneficial to SONET networks, phased array radar networks, very high speed oscilloscopes, all-optical networks, IR countermeasure systems, BER equipment, and the fast growing video conferencing network market. The novel all-optical crossbar switch developed in this program will solve interconnect problems. and will be a key component in the widely proposed all-optical 200 Gb/s SONET/ATM networks.

  10. Arduino Based RFID Line Switching Using SSR

    Directory of Open Access Journals (Sweden)

    Michael E.

    2017-10-01

    Full Text Available The importance of line switching cannot be overemphasized as they are used to connect and disconnect substations to and from a distribution grid. At the cradle of technology line switching was achieved via the use of manual switches or fuses which could endanger life as a result of electrocution when expose during maintenance. This ill prompted the development of automated line switching using relays and contactors. With time this tends to fail as a result of wearing of the contact which is as a result of arcing and low voltage. To avert all these ills this paper presents Arduino based Radio Frequency Identification RFID line switching using Solid State Relay SSR. This is to ensure the safety of operators or technologist and to also avert the problem associated with relays and contactors using SSR. This was achieved using RFID RC-522 reader ardriuno Uno SSR and other discrete components. The system was tested and worked perfectly reducing the risk of electrocution and eliminating damage wearing of the contacts common with contactors and relays.

  11. Optically coupled cavities for wavelength switching

    Energy Technology Data Exchange (ETDEWEB)

    Costazo-Caso, Pablo A; Granieri, Sergio; Siahmakoun, Azad, E-mail: pcostanzo@ing.unlp.edu.ar, E-mail: granieri@rose-hulman.edu, E-mail: siahmako@rose-hulman.edu [Department of Physics and Optical Engineering, Rose-Hulman Institute of Technology, 5500 Wabash Avenue, Terre Haute, IN 47803 (United States)

    2011-01-01

    An optical bistable device which presents hysteresis behavior is proposed and experimentally demonstrated. The system finds applications in wavelength switching, pulse reshaping and optical bistability. It is based on two optically coupled cavities named master and slave. Each cavity includes a semiconductor optical amplifier (SOA), acting as the gain medium of the laser, and two pair of fiber Bragg gratings (FBG) which define the lasing wavelength (being different in each cavity). Finally, a variable optical coupler (VOC) is employed to couple both cavities. Experimental characterization of the system performance is made analyzing the effects of the coupling coefficient between the two cavities and the driving current in each SOA. The properties of the hysteretic bistable curve and switching can be controlled by adjusting these parameters and the loss in the cavities. By selecting the output wavelength ({lambda}{sub 1} or {lambda}{sub 2}) with an external filter it is possible to choose either the invert or non-invert switched signal. Experiments were developed employing both optical discrete components and a photonic integrated circuit. They show that for 8 m-long cavities the maximum switching frequency is about 500 KHz, and for 4 m-long cavities a minimum rise-time about 21 ns was measured. The switching time can be reduced by shortening the cavity lengths and using photonic integrated circuits.

  12. Commitment and Switching Intentions: Customers and Brands

    Directory of Open Access Journals (Sweden)

    Juliana Werneck Rodrigues

    2012-12-01

    Full Text Available This study aims to evaluate the relationship between a customer’s brand switching intentions and his commitment to a brand. Based on a literature review, constructs related to customer brand commitment were identified (affective and continuance commitment, trust, satisfaction, switching costs and alternative attractiveness and their roles in the formation of brand switching intentions hypothesized. Through a cross-sectional survey, a sample of 201 smartphone users was collected to test the proposed relationships. Data analysis was carried out via structural equations modeling, with direct effects of trust, satisfaction, switching costs and alternative attractiveness upon the different kinds of commitment being verified. Furthermore, both types of brand commitment (affective and continuance were found to negatively impact a customer’s intention to switch brands. Regarding enterprise customer strategies, the research findings suggest that, if firms are able to track customer brand commitment, they could use such knowledge to develop better relationship strategies, minimizing customer defection and further developing customer value to the company.

  13. The double switch for atrioventricular discordance.

    Science.gov (United States)

    Brawn, William J

    2005-01-01

    Conventional surgery for atrioventricular discordance usually associated with ventricular arterial discordance leaves the morphologic right ventricle in the systemic circulation. Long-term follow-up results with this approach reveal a high incidence of right ventricular failure. The double switch procedure was introduced to restore the morphologic left ventricle to the systemic circulation. This operation is performed in two main ways: the atrial-arterial switch and the atrial switch plus Rastelli procedure. This double switch approach has been successful at least in the medium term in abolishing morphologic right ventricular failure and its associated tricuspid valve regurgitation. In the atrial-arterial switch group, there is an incidence of morphologic left ventricular dysfunction, sometimes associated with neoaortic valve regurgitation, and the minority of cases need aortic valve replacement. The long-term function of the morphologic left ventricle and the aortic valve need careful surveillance in the future. The atrial-Rastelli group of patients has not in the medium term shown evidence of ventricular dysfunction but will require change on a regular basis of their ventricular to pulmonary artery valved conduits.

  14. The gradual nature of threshold switching

    International Nuclear Information System (INIS)

    Wimmer, M; Salinga, M

    2014-01-01

    The recent commercialization of electronic memories based on phase change materials proved the usability of this peculiar family of materials for application purposes. More advanced data storage and computing concepts, however, demand a deeper understanding especially of the electrical properties of the amorphous phase and the switching behaviour. In this work, we investigate the temporal evolution of the current through the amorphous state of the prototypical phase change material, Ge 2 Sb 2 Te 5 , under constant voltage. A custom-made electrical tester allows the measurement of delay times over five orders of magnitude, as well as the transient states of electrical excitation prior to the actual threshold switching. We recognize a continuous current increase over time prior to the actual threshold-switching event to be a good measure for the electrical excitation. A clear correlation between a significant rise in pre-switching-current and the later occurrence of threshold switching can be observed. This way, we found experimental evidence for the existence of an absolute minimum for the threshold voltage (or electric field respectively) holding also for time scales far beyond the measurement range. (paper)

  15. A Superconducting Dual-Channel Photonic Switch.

    Science.gov (United States)

    Srivastava, Yogesh Kumar; Manjappa, Manukumara; Cong, Longqing; Krishnamoorthy, Harish N S; Savinov, Vassili; Pitchappa, Prakash; Singh, Ranjan

    2018-06-05

    The mechanism of Cooper pair formation and its underlying physics has long occupied the investigation into high temperature (high-T c ) cuprate superconductors. One of the ways to unravel this is to observe the ultrafast response present in the charge carrier dynamics of a photoexcited specimen. This results in an interesting approach to exploit the dissipation-less dynamic features of superconductors to be utilized for designing high-performance active subwavelength photonic devices with extremely low-loss operation. Here, dual-channel, ultrafast, all-optical switching and modulation between the resistive and the superconducting quantum mechanical phase is experimentally demonstrated. The ultrafast phase switching is demonstrated via modulation of sharp Fano resonance of a high-T c yttrium barium copper oxide (YBCO) superconducting metamaterial device. Upon photoexcitation by femtosecond light pulses, the ultrasensitive cuprate superconductor undergoes dual dissociation-relaxation dynamics, with restoration of superconductivity within a cycle, and thereby establishes the existence of dual switching windows within a timescale of 80 ps. Pathways are explored to engineer the secondary dissociation channel which provides unprecedented control over the switching speed. Most importantly, the results envision new ways to accomplish low-loss, ultrafast, and ultrasensitive dual-channel switching applications that are inaccessible through conventional metallic and dielectric based metamaterials. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Launched electrons in plasma opening switches

    International Nuclear Information System (INIS)

    Mendel, C.W. Jr.; Rochau, G.E.; Sweeney, M.A.; McDaniel, D.H.; Quintenz, J.P.; Savage, M.E.; Lindman, E.L.; Kindel, J.M.

    1989-01-01

    Plasma opening switches have provided a means to improve the characteristics of super-power pulse generators. Recent advances involving plasma control with fast and slow magnetic fields have made these switches more versatile, allowing for improved switch uniformity, triggering, and opening current levels that are set by the level of auxiliary fields. Such switches necessarily involve breaks in the translational symmetry of the transmission line geometry and therefore affect the electron flow characteristics of the line. These symmetry breaks are the result of high electric field regions caused by plasma conductors remaining in the transmission line, ion beams crossing the line, or auxilliary magnetic field regions. Symmetry breaks cause the canonical momentum of the electrons to change, thereby moving them away from the cathode. Additional electrons are pulled from the cathode into the magnetically insulated flow, resulting in an excess of electron flow over that expected for the voltage and line current downstream of the switch. We call these electrons ''launched electrons''. Unless they are recaptured at the cathode or else are fed into the load and used beneficially, they cause a large power loss downstream. This paper will show examples of SuperMite and PBFA II data showing these losses, explain the tools we are using to study them, and discuss the mechanisms we will employ to mitigate the problem. The losses will be reduced primarily by reducing the amount of launched electron flow. 7 refs., 9 figs

  17. Engineering Silver Nanowire Networks: From Transparent Electrodes to Resistive Switching Devices.

    Science.gov (United States)

    Du, Haiwei; Wan, Tao; Qu, Bo; Cao, Fuyang; Lin, Qianru; Chen, Nan; Lin, Xi; Chu, Dewei

    2017-06-21

    Metal nanowires (NWs) networks with high conductance have shown potential applications in modern electronic components, especially the transparent electrodes over the past decade. In metal NW networks, the electrical connectivity of nanoscale NW junction can be modulated for various applications. In this work, silver nanowire (Ag NW) networks were selected to achieve the desired functions. The Ag NWs were first synthesized by a classic polyol process, and spin-coated on glass to fabricate transparent electrodes. The as-fabricated electrode showed a sheet resistance of 7.158 Ω □ -1 with an optical transmittance of 79.19% at 550 nm, indicating a comparable figure of merit (FOM, or Φ TC ) (13.55 × 10 -3 Ω -1 ). Then, two different post-treatments were designed to tune the Ag NWs for not only transparent electrode but also for threshold resistive switching (RS) application. On the one hand, the Ag NW film was mechanically pressed to significantly improve the conductance by reducing the junction resistance. On the other hand, an Ag@AgO x core-shell structure was deliberately designed by partial oxidation of Ag NWs through simple ultraviolet (UV)-ozone treatment. The Ag core can act as metallic interconnect and the insulating AgO x shell acts as a switching medium to provide a conductive pathway for Ag filament migration. By fabricating Ag/Ag@AgO x /Ag planar structure, a volatile threshold switching characteristic was observed and an on/off ratio of ∼100 was achieved. This work showed that through different post-treatments, Ag NW network can be engineered for diverse functions, transforming from transparent electrodes to RS devices.

  18. FY 1990 report on the results of the development of the entrained bed coal gasification power plant. Part 3. Fabrication/installation of pilot plant (Fabrication/installation drawings and fabrication/installation pictures - 2/2); 1990 nendo seika hokokusho. Funryusho sekitan gaska hatsuden plant kaihatsu - Sono 3. Pilot plant seisaku suetsuke hen (Seisaku suetsukezu oyobi seisaku suetsuke shashin) (2/2)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-03-01

    For the purpose of establishing the technology of the integrated coal gasification combined cycle power generation, the fabrication, installation work, etc. were conducted of a 200t/d entrained bed coal gasification pilot plant, and fabrication/installation drawings and fabrication/installation pictures were summarized. In fabrication/installation drawings, drawings of the following were included: actual-pressure/actual-size combustor test equipment (structural drawing of exhaust temperature reducing device, structural drawing of hot air device, system diagram of piping, etc.), safety environmental equipment (total system diagram, layout of electric room equipment, layout of control equipment room, etc.), total control system (structural drawing of the total control system, front view of auxiliary panel of safety environment equipment, etc.), 66kV/6.9kV indoor switching station facilities (layout of equipment of indoor switching station facilities, outline drawing of the main transformer, outline drawing of gas circuit breaker, etc.), common facilities (total layout, diagram of the nitrogen gas pipe system, system diagram of utility equipment, etc.) In pictures of fabrication/installation, pictures of the following were included: state of the construction work, gasifier equipment, gas refining facilities, gas turbine facilities, actual-pressure/actual-size combustor test equipment, safety environmental equipment, total control system, 66kV/6.9kV indoor switching station facilities, common facilities. (NEDO)

  19. Highly uniform bipolar resistive switching characteristics in TiO2/BaTiO3/TiO2 multilayer

    International Nuclear Information System (INIS)

    Ma, W. J.; Zhang, X. Y.; Wang, Ying; Zheng, Yue; Lin, S. P.; Luo, J. M.; Wang, B.; Li, Z. X.

    2013-01-01

    Nanoscale multilayer structure TiO 2 /BaTiO 3 /TiO 2 has been fabricated on Pt/Ti/SiO 2 /Si substrate by chemical solution deposition method. Highly uniform bipolar resistive switching (BRS) characteristics have been observed in Pt/TiO 2 /BaTiO 3 /TiO 2 /Pt cells. Analysis of the current-voltage relationship demonstrates that the space-charge-limited current conduction controlled by the localized oxygen vacancies should be important to the resistive switching behavior. X-ray photoelectron spectroscopy results indicated that oxygen vacancies in TiO 2 play a crucial role in the resistive switching phenomenon and the introduced TiO 2 /BaTiO 3 interfaces result in the high uniformity of bipolar resistive switching characteristics

  20. Resistive switching of organic–inorganic hybrid devices of conductive polymer and permeable ultra-thin SiO2 films

    Science.gov (United States)

    Yamamoto, Shunsuke; Kitanaka, Takahisa; Miyashita, Tokuji; Mitsuishi, Masaya

    2018-06-01

    We propose a resistive switching device composed of conductive polymer (PEDOT:PSS) and SiO2 ultra-thin films. The SiO2 film was fabricated from silsesquioxane polymer nanosheets as a resistive switching layer. Devices with metal (Ag or Au)∣SiO2∣PEDOT:PSS architecture show good resistive switching performance with set–reset voltages as low as several hundred millivolts. The device properties and the working mechanism were investigated by varying the electrode material, surrounding atmosphere, and SiO2 film thickness. Results show that resistive switching is based on water and ion migration at the PEDOT:PSS∣SiO2 interface.

  1. MOX fuel fabrication at AECL

    International Nuclear Information System (INIS)

    Dimayuga, F.C.; Jeffs, A.T.

    1995-01-01

    Atomic Energy of Canada Limited's mixed-oxide (MOX) fuel fabrication activities are conducted in the Recycle Fuel Fabrication Laboratories (RFFL) at the Chalk River Laboratories. The RFFL facility is designed to produce experimental quantities of CANDU MOX fuel for reactor physics tests or demonstration irradiations. From 1979 to 1987, several MOX fuel fabrication campaigns were run in the RFFL, producing various quantities of fuel with different compositions. About 150 bundles, containing over three tonnes of MOX, were fabricated in the RFFL before operations in the facility were suspended. In late 1987, the RFFL was placed in a state of active standby, a condition where no fuel fabrication activities are conducted, but the monitoring and ventilation systems in the facility are maintained. Currently, a project to rehabilitate the RFFL and resume MOX fuel fabrication is nearing completion. This project is funded by the CANDU Owners' Group (COG). The initial fabrication campaign will consist of the production of thirty-eight 37-element (U,Pu)O 2 bundles containing 0.2 wt% Pu in Heavy Element (H.E.) destined for physics tests in the zero-power ZED-2 reactor. An overview of the Rehabilitation Project will be given. (author)

  2. A highly efficient graphene oxide absorber for Q-switched Nd:GdVO4 lasers

    International Nuclear Information System (INIS)

    Wang Yonggang; Wen Xiaoming; Tang Jau; Chen, Hou Ren; Hsieh, Wen Feng

    2011-01-01

    We demonstrated that graphene oxide material could be used as a highly efficient saturable absorber for the Q-switched Nd:GdVO 4 laser. A novel and low-cost graphene oxide (GO) absorber was fabricated by a vertical evaporation technique and high viscosity of polyvinyl alcohol (PVA) aqueous solution. A piece of GO/PVA absorber, a piece of round quartz, and an output coupler mirror were combined to be a sandwich structure passive component. Using such a structure, 104 ns pulses and 1.22 W average output power were obtained with the maximum pulse energy at 2 µJ and a slope efficiency of 17%.

  3. Development of laser marking system with electro-optic Q-switch

    International Nuclear Information System (INIS)

    Kim, Cheol Jung; Kim, Jeong Moog; Kim, Kwang Suk; Park, Seung Kyu; Baik, Sung Hoon.

    1995-11-01

    We developed a high repetition electro-optic Q switch Nd:YAG laser and scan system for laser marking. We localized the scan mirrors and their mounts. We made the database for the optical properties of commercial flat-field lenses with our optics design software. We fabricated the detailed network between the galvanometer based beam scanning system and the laser generator. To accelerate the commercialization by the joint company, the training and transfer of technology were pursued in the joint participation by company researchers from the early stage. (author). 8 refs., 6 tabs., 27 figs

  4. Development of laser marking system with electro-optic Q-switch

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Cheol Jung; Kim, Jeong Moog; Kim, Kwang Suk; Park, Seung Kyu; Baik, Sung Hoon

    1995-11-01

    We developed a high repetition electro-optic Q switch Nd:YAG laser and scan system for laser marking. We localized the scan mirrors and their mounts. We made the database for the optical properties of commercial flat-field lenses with our optics design software. We fabricated the detailed network between the galvanometer based beam scanning system and the laser generator. To accelerate the commercialization by the joint company, the training and transfer of technology were pursued in the joint participation by company researchers from the early stage. (author). 8 refs., 6 tabs., 27 figs.

  5. Fabric circuits and method of manufacturing fabric circuits

    Science.gov (United States)

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

    2011-01-01

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

  6. Fabrication of cotton fabric with superhydrophobicity and flame retardancy.

    Science.gov (United States)

    Zhang, Ming; Wang, Chengyu

    2013-07-25

    A simple and facile method for fabricating the cotton fabric with superhydrophobicity and flame retardancy is described in the present work. The cotton fabric with the maximal WCA of 160° has been prepared by the covalent deposition of amino-silica nanospheres and the further graft with (heptadecafluoro-1,1,2,2-tetradecyl) trimethoxysilane. The geometric microstructure of silica spheres was measured by transmission electron microscopy (TEM). The cotton textiles before and after treatment were characterized by using scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). The wetting behavior of cotton samples was investigated by water contact angle measurement. Moreover, diverse performances of superhydrophobic cotton textiles have been evaluated as well. The results exhibited the outstanding superhydrophobicity, excellent waterproofing durability and flame retardancy of the cotton fabric after treatment, offering a good opportunity to accelerate the large-scale production of superhydrophobic textiles materials for new industrial applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Intermittent metabolic switching, neuroplasticity and brain health

    Science.gov (United States)

    Mattson, Mark P.; Moehl, Keelin; Ghena, Nathaniel; Schmaedick, Maggie; Cheng, Aiwu

    2018-01-01

    During evolution, individuals whose brains and bodies functioned well in a fasted state were successful in acquiring food, enabling their survival and reproduction. With fasting and extended exercise, liver glycogen stores are depleted and ketones are produced from adipose-cell-derived fatty acids. This metabolic switch in cellular fuel source is accompanied by cellular and molecular adaptations of neural networks in the brain that enhance their functionality and bolster their resistance to stress, injury and disease. Here, we consider how intermittent metabolic switching, repeating cycles of a metabolic challenge that induces ketosis (fasting and/or exercise) followed by a recovery period (eating, resting and sleeping), may optimize brain function and resilience throughout the lifespan, with a focus on the neuronal circuits involved in cognition and mood. Such metabolic switching impacts multiple signalling pathways that promote neuroplasticity and resistance of the brain to injury and disease. PMID:29321682

  8. High power switches for ion induction linacs

    International Nuclear Information System (INIS)

    Humphries, S.; Savage, M.; Saylor, W.B.

    1985-01-01

    The success of linear induction ion accelerators for accelerator inertial fusion (AIF) applications depends largely on innovations in pulsed power technology. There are tight constraints on the accuracy of accelerating voltage waveforms to maintain a low momentum spread. Furthermore, the non-relativistic ion beams may be subject to a klystronlike interaction with the accelerating cavities, leading to enhanced momentum spread. In this paper, we describe a novel high power switch with a demonstrated ability to interrupt 300 A at 20 kV in less than 60 ns. The switch may allow the replacement of pulse modulators in linear induction accelerators with hard tube pulsers. A power system based on a hard tube pulser could solve the longitudinal instability problem while maintaining high energy transfer efficiency. The problem of longitudinal beam control in ion induction linacs is reviewed in Section 2. Section 3 describes the principles of the plasma flow switch. Experimental results are summarized in Section 4

  9. Nanoeletromechanical switch and logic circuits formed therefrom

    Science.gov (United States)

    Nordquist, Christopher D [Albuquerque, NM; Czaplewski, David A [Albuquerque, NM

    2010-05-18

    A nanoelectromechanical (NEM) switch is formed on a substrate with a source electrode containing a suspended electrically-conductive beam which is anchored to the substrate at each end. This beam, which can be formed of ruthenium, bows laterally in response to a voltage applied between a pair of gate electrodes and the source electrode to form an electrical connection between the source electrode and a drain electrode located near a midpoint of the beam. Another pair of gate electrodes and another drain electrode can be located on an opposite side of the beam to allow for switching in an opposite direction. The NEM switch can be used to form digital logic circuits including NAND gates, NOR gates, programmable logic gates, and SRAM and DRAM memory cells which can be used in place of conventional CMOS circuits, or in combination therewith.

  10. Metallic oxide switches using thick film technology

    Science.gov (United States)

    Patel, D. N.; Williams, L., Jr.

    1974-01-01

    Metallic oxide thick film switches were processed on alumina substrates using thick film technology. Vanadium pentoxide in powder form was mixed with other oxides e.g., barium, strontium copper and glass frit, ground to a fine powder. Pastes and screen printable inks were made using commercial conductive vehicles and appropriate thinners. Some switching devices were processed by conventional screen printing and firing of the inks and commercial cermet conductor terminals on 96% alumina substrates while others were made by applying small beads or dots of the pastes between platinum wires. Static, and dynamic volt-ampere, and pulse tests indicate that the switching and self-oscillatory characteristics of these devices could make them useful in memory element, oscillator, and automatic control applications.

  11. High power switches for ion induction linacs

    International Nuclear Information System (INIS)

    Humphries, S. Jr.; Savage, M.; Saylor, W.B.

    1985-01-01

    The success of linear induction ion accelerators for accelerator inertial fusion (AIF) applications depends largely on innovations in pulsed power technology. There are tight constraints on the accuracy of accelerating voltage waveforms to maintain a low momentum spread. Furthermore, the non-relativistic ion beams may be subject to a klystron-like interaction with the accelerating cavities leading to enhanced momentum spread. In this paper, the author describe a novel high power switch with a demonstrated ability to interrupt 300 A at 20 kV in less than 60 ns. The switch may allow the replacement of pulse modulators in linear induction accelerators with hard tube pulsers. A power system based on a hard tube pulser could solve the longitudinal instability problem while maintaining high energy transfer efficiency. The problem of longitudinal beam control in ion induction linacs is reviewed in Section 2. Section 3 describes the principles of the plasma flow switch. Experimental results are summarized in Section 4

  12. A nanoplasmonic switch based on molecular machines

    KAUST Repository

    Zheng, Yue Bing

    2009-06-01

    We aim to develop a molecular-machine-driven nanoplasmonic switch for its use in future nanophotonic integrated circuits (ICs) that have applications in optical communication, information processing, biological and chemical sensing. Experimental data show that an Au nanodisk array, coated with rotaxane molecular machines, switches its localized surface plasmon resonances (LSPR) reversibly when it is exposed to chemical oxidants and reductants. Conversely, bare Au nanodisks and disks coated with mechanically inert control compounds, do not display the same switching behavior. Along with calculations based on time-dependent density functional theory (TDDFT), these observations suggest that the nanoscale movements within surface-bound "molecular machines" can be used as the active components in plasmonic devices. ©2009 IEEE.

  13. Coupled qubits as a quantum heat switch

    Science.gov (United States)

    Karimi, B.; Pekola, J. P.; Campisi, M.; Fazio, R.

    2017-12-01

    We present a quantum heat switch based on coupled superconducting qubits, connected to two LC resonators that are terminated by resistors providing two heat baths. To describe the system, we use a standard second order master equation with respect to coupling to the baths. We find that this system can act as an efficient heat switch controlled by the applied magnetic flux. The flux influences the energy level separations of the system, and under some conditions, the finite coupling of the qubits enhances the transmitted power between the two baths, by an order of magnitude under realistic conditions. At the same time, the bandwidth at maximum power of the switch formed of the coupled qubits is narrowed.

  14. The Aurora accelerator's triggered oil switch

    International Nuclear Information System (INIS)

    Weidenheimer, D.M.; Pereira, N.R.; Judy, D.C.; Stricklett, K.L.

    1993-01-01

    Achieving a radiation pulse with 15 ns risetime using all four of the Aurora accelerator's Blumlein pulse-forming lines demands synchronization of the Blumleins to within 10 ns (in addition to a 15 ns risetime for a single line). Timing of each Blumlein is controlled by a triggered 12 MV oil switch. A smaller-than-customary trigger electrode makes the switching time more reproducible. Time-resolved photography of the oil arcs suggests that triggering occurs simultaneously around the sharp edge of the trigger electrode, perhaps with small deviations that grow into the most prominent arcs characteristically seen in open-shutter photographs. However, many smaller arcs that are usually overlooked in open-shutter pictures may contribute to current conduction in a closed switch

  15. Plasma opening switch experiments on supermite

    International Nuclear Information System (INIS)

    Mendel, C.W.; Quintenz, J.P.; Rosenthal, S.E.; Savage, M.E.

    1988-01-01

    Experiments using plasma opening switches with fast field coils and plasmas injected on slow magnetic fields are described. Data showing the measurement of the field penetration into the volume that initially held the plasma fill will be shown. Assuming the plasma is mostly pushed back from the coil, rather than being penetrated by the magnetic field allows the density to be calculated, and gives densities of a few times 10 13 cm -3 for our usual operating range. The data makes it clear that the switch is open well before the initial plasma volume is completely penetrated by the magnetic fields. Additional measurements relating to the magnetic field penetration distance and physical penetration mechanism are presented. Other data presented show a magnetic insulation problem which must be solved before very large voltage multiplication can be accomplished with sufficient switch efficiency

  16. Radio frequency-assisted fast superconducting switch

    Science.gov (United States)

    Solovyov, Vyacheslav; Li, Qiang

    2017-12-05

    A radio frequency-assisted fast superconducting switch is described. A superconductor is closely coupled to a radio frequency (RF) coil. To turn the switch "off," i.e., to induce a transition to the normal, resistive state in the superconductor, a voltage burst is applied to the RF coil. This voltage burst is sufficient to induce a current in the coupled superconductor. The combination of the induced current with any other direct current flowing through the superconductor is sufficient to exceed the critical current of the superconductor at the operating temperature, inducing a transition to the normal, resistive state. A by-pass MOSFET may be configured in parallel with the superconductor to act as a current shunt, allowing the voltage across the superconductor to drop below a certain value, at which time the superconductor undergoes a transition to the superconducting state and the switch is reset.

  17. CMOS SPDT switch for WLAN applications

    International Nuclear Information System (INIS)

    Bhuiyan, M A S; Reaz, M B I; Rahman, L F; Minhad, K N

    2015-01-01

    WLAN has become an essential part of our today's life. The advancement of CMOS technology let the researchers contribute low power, size and cost effective WLAN devices. This paper proposes a single pole double through transmit/receive (T/R) switch for WLAN applications in 0.13 μm CMOS technology. The proposed switch exhibit 1.36 dB insertion loss, 25.3 dB isolation and 24.3 dBm power handling capacity. Moreover, it only dissipates 786.7 nW power per cycle. The switch utilizes only transistor aspect ratio optimization and resistive body floating technique to achieve such desired performance. In this design the use of bulky inductor and capacitor is avoided to evade imposition of unwanted nonlinearities to the communication signal. (paper)

  18. Cmos spdt switch for wlan applications

    Science.gov (United States)

    Bhuiyan, M. A. S.; Reaz, M. B. I.; Rahman, L. F.; Minhad, K. N.

    2015-04-01

    WLAN has become an essential part of our today's life. The advancement of CMOS technology let the researchers contribute low power, size and cost effective WLAN devices. This paper proposes a single pole double through transmit/receive (T/R) switch for WLAN applications in 0.13 μm CMOS technology. The proposed switch exhibit 1.36 dB insertion loss, 25.3 dB isolation and 24.3 dBm power handling capacity. Moreover, it only dissipates 786.7 nW power per cycle. The switch utilizes only transistor aspect ratio optimization and resistive body floating technique to achieve such desired performance. In this design the use of bulky inductor and capacitor is avoided to evade imposition of unwanted nonlinearities to the communication signal.

  19. A new Zero-Current-Transition PWM switching cell

    Energy Technology Data Exchange (ETDEWEB)

    Grigore, V. [Electronics and Telecommunications Faculty, `Politechnica` University Bucharest (Romania); Kyyrae, J. [Helsinki University of Technology, Otaniemi (Finland): Institute of Intelligent Power Electronics

    1997-12-31

    In this paper a new Zero-Current-Transition (ZCT) PWM switching cell is presented. The proposed switching cell is composed of the normal hard-switched PWM cell (consisting of one active switch and one passive switch), plus as auxiliary circuit. The auxiliary circuit is inactive during the ON ad OFF intervals of the switches in the normal PWM switch. The transitions between the two states are controlled by the auxiliary circuit. Prior to turn-off, the current through the active switch in the PWM cell is forced to zero, thus the turn-off losses of the active switch are practically eliminated. At turn-on the auxiliary circuit slows down the growing rate of the current through the main switch. Thus, turn-on losses are also very much reduced. The active switch operates under ZCT conditions, the passive switch (diode) has a controlled reverse recovery, while the switch in the auxiliary circuit operates under Zero-Current-Switching (ZCS) conditions. (orig.) 3 refs.

  20. Ultra High-Speed Radio Frequency Switch Based on Photonics.

    Science.gov (United States)

    Ge, Jia; Fok, Mable P

    2015-11-26

    Microwave switches, or Radio Frequency (RF) switches have been intensively used in microwave systems for signal routing. Compared with the fast development of microwave and wireless systems, RF switches have been underdeveloped particularly in terms of switching speed and operating bandwidth. In this paper, we propose a photonics based RF switch that is capable of switching at tens of picoseconds speed, which is hundreds of times faster than any existing RF switch technologies. The high-speed switching property is achieved with the use of a rapidly tunable microwave photonic filter with tens of gigahertz frequency tuning speed, where the tuning mechanism is based on the ultra-fast electro-optics Pockels effect. The RF switch has a wide operation bandwidth of 12 GHz and can go up to 40 GHz, depending on the bandwidth of the modulator used in the scheme. The proposed RF switch can either work as an ON/OFF switch or a two-channel switch, tens of picoseconds switching speed is experimentally observed for both type of switches.

  1. Fabrication of nanowires and nanostructures

    DEFF Research Database (Denmark)

    Mátéfi-Tempfli, Stefan; Mátéfi-Tempfli, M.; Piraux, L.

    2009-01-01

    We report on different approaches that we have adopted and developed for the fabrication of nanowires and nanostructures. Methods based on template synthesis and on self organization seem to be the most promising for the fabrication of nanomaterials and nanostructures due to their easiness and low...... cost. The development of a supported nanoporous alumina template and the possibility of using this template to combine electrochemical synthesis with lithographic methods open new ways for the fabrication of complex nanostructures. The numerous advantages of the supported template and its compatibility...

  2. Quantum Bridge Fabrication Using Photolithography

    International Nuclear Information System (INIS)

    Quinones, R.

    2001-01-01

    The need for high-speed performance electronics in computers integrated circuits and sensors, require the fabrication of low energy consumption diodes. Nano fabrication methods require new techniques and equipment. We are currently developing a procedure to fabricate a diode based on quantum-effects. The device will act like a traditional diode, but the nanometer scale will allow it to reach high speeds without over heating. This new diode will be on a nano-bridge so it can be attenuated by an electromagnetic wave. The goal is to obtain similar current vs voltage response as in a silicon diode

  3. Fabricating Copper Nanotubes by Electrodeposition

    Science.gov (United States)

    Yang, E. H.; Ramsey, Christopher; Bae, Youngsam; Choi, Daniel

    2009-01-01

    Copper tubes having diameters between about 100 and about 200 nm have been fabricated by electrodeposition of copper into the pores of alumina nanopore membranes. Copper nanotubes are under consideration as alternatives to copper nanorods and nanowires for applications involving thermal and/or electrical contacts, wherein the greater specific areas of nanotubes could afford lower effective thermal and/or electrical resistivities. Heretofore, copper nanorods and nanowires have been fabricated by a combination of electrodeposition and a conventional expensive lithographic process. The present electrodeposition-based process for fabricating copper nanotubes costs less and enables production of copper nanotubes at greater rate.

  4. Photonic Switching Devices Using Light Bullets

    Science.gov (United States)

    Goorjian, Peter M. (Inventor)

    1999-01-01

    A unique ultra-fast, all-optical switching device or switch is made with readily available, relatively inexpensive, highly nonlinear optical materials. which includes highly nonlinear optical glasses, semiconductor crystals and/or multiple quantum well semiconductor materials. At the specified wavelengths. these optical materials have a sufficiently negative group velocity dispersion and high nonlinear index of refraction to support stable light bullets. The light bullets counter-propagate through, and interact within the waveguide to selectively change each others' directions of propagation into predetermined channels. In one embodiment, the switch utilizes a rectangularly planar slab waveguide. and further includes two central channels and a plurality of lateral channels for guiding the light bullets into and out of the waveguide. An advantage of the present all-optical switching device lies in its practical use of light bullets, thus preventing the degeneration of the pulses due to dispersion and diffraction at the front and back of the pulses. Another advantage of the switching device is the relative insensitivity of the collision process to the time difference in which the counter-propagating pulses enter the waveguide. since. contrary to conventional co-propagating spatial solitons, the relative phase of the colliding pulses does not affect the interaction of these pulses. Yet another feature of the present all-optical switching device is the selection of the light pulse parameters which enables the generation of light bullets in nonlinear optical materials. including highly nonlinear optical glasses and semiconductor materials such as semiconductor crystals and/or multiple quantum well semiconductor materials.

  5. Manufacturing fuel-switching capability, 1988

    International Nuclear Information System (INIS)

    1991-09-01

    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

  6. Two Bistable Switches Govern M Phase Entry.

    Science.gov (United States)

    Mochida, Satoru; Rata, Scott; Hino, Hirotsugu; Nagai, Takeharu; Novák, Béla

    2016-12-19

    The abrupt and irreversible transition from interphase to M phase is essential to separate DNA replication from chromosome segregation. This transition requires the switch-like phosphorylation of hundreds of proteins by the cyclin-dependent kinase 1 (Cdk1):cyclin B (CycB) complex. Previous studies have ascribed these switch-like phosphorylations to the auto-activation of Cdk1:CycB through the removal of inhibitory phosphorylations on Cdk1-Tyr15 [1, 2]. The positive feedback in Cdk1 activation creates a bistable switch that makes mitotic commitment irreversible [2-4]. Here, we surprisingly find that Cdk1 auto-activation is dispensable for irreversible, switch-like mitotic entry due to a second mechanism, whereby Cdk1:CycB inhibits its counteracting phosphatase (PP2A:B55). We show that the PP2A:B55-inhibiting Greatwall (Gwl)-endosulfine (ENSA) pathway is both necessary and sufficient for switch-like phosphorylations of mitotic substrates. Using purified components of the Gwl-ENSA pathway in a reconstituted system, we found a sharp Cdk1 threshold for phosphorylation of a luminescent mitotic substrate. The Cdk1 threshold to induce mitotic phosphorylation is distinctly higher than the Cdk1 threshold required to maintain these phosphorylations-evidence for bistability. A combination of mathematical modeling and biochemical reconstitution show that the bistable behavior of the Gwl-ENSA pathway emerges from its mutual antagonism with PP2A:B55. Our results demonstrate that two interlinked bistable mechanisms provide a robust solution for irreversible and switch-like mitotic entry. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Manufacturing fuel-switching capability, 1988

    Energy Technology Data Exchange (ETDEWEB)

    1991-09-01

    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.

  8. Natural fabric of Hildegardia populifolia composites

    CSIR Research Space (South Africa)

    Guduri, BBR

    2006-12-01

    Full Text Available The influence of Hildegardia populofolia fabric content, fabric orientation, sodium hydroxide (NaOH) and silane coupling agent treatment on the surface properties of the fabric, mechanical and fracture properties of Hildegardia populifolia...

  9. Properties of natural fabric Polyalthia cerasoides

    CSIR Research Space (South Africa)

    Jayaramudu, J

    2009-06-01

    Full Text Available of this fabric were compared with those of two natural fabrics reported in the literature. This uniaxial fabric has sufficient tensile modulus and can be used as reinforcement in the development of green composites....

  10. Optical burst switching based satellite backbone network

    Science.gov (United States)

    Li, Tingting; Guo, Hongxiang; Wang, Cen; Wu, Jian

    2018-02-01

    We propose a novel time slot based optical burst switching (OBS) architecture for GEO/LEO based satellite backbone network. This architecture can provide high speed data transmission rate and high switching capacity . Furthermore, we design the control plane of this optical satellite backbone network. The software defined network (SDN) and network slice (NS) technologies are introduced. Under the properly designed control mechanism, this backbone network is flexible to support various services with diverse transmission requirements. Additionally, the LEO access and handoff management in this network is also discussed.

  11. Simulation of plasma erosion opening switches

    International Nuclear Information System (INIS)

    Mason, R.J.; Jones, M.E.

    1988-01-01

    Recent progress in the modeling of Plasma Erosion Opening Switches is reviewed, and new results from both fluid and particle simulation compared. Three-fluid simulations with the ANTHEM code for switches on the NRL GAMBLE I machine and SNL PBFA II machine have shown strong dependence of the opening dynamics on the anode structure, the threshold for electron emission, on the possible presence of anomalous resistivity, and on advection of the magnetic field with cathode emitted electrons. Simulations with the implicit particle-in-cell code ISIS confirm these observations, but manifest broader current channels---in better agreement with GAMBLE I experimental results. 7 refs., 3 figs

  12. Noise in Genetic Toggle Switch Models

    Directory of Open Access Journals (Sweden)

    Andrecut M.

    2006-06-01

    Full Text Available In this paper we study the intrinsic noise effect on the switching behavior of a simple genetic circuit corresponding to the genetic toggle switch model. The numerical results obtained from a noisy mean-field model are compared to those obtained from the stochastic Gillespie simulation of the corresponding system of chemical reactions. Our results show that by using a two step reaction approach for modeling the transcription and translation processes one can make the system to lock in one of the steady states for exponentially long times.

  13. Switching to a Mac For Dummies

    CERN Document Server

    Reinhold, Arnold

    2007-01-01

    Thinking of making the switch from your PC to a Mac? Congratulations! You're in for a great, virus-free ride. And Switching to Mac For Dummies makes it smoother than you ever imagined. From buying the Mac that's right for you to transferring your files to breaking your old Windows habits and learning to do things the (much easier) Mac way, it makes the whole process practically effortless. Whether you've been using Windows XP, Vista, or even Linux, you'll find simple, straightforward ways to make your transition go smoothly. That will leave you plenty of time to get familiar with Mac'

  14. Design of a Clap Activated Switch

    Directory of Open Access Journals (Sweden)

    Seyi Stephen OLOKEDE

    2008-12-01

    Full Text Available This paper presents the design of a clap activated switch device that will serve well in different phono-controlled applications, providing inexpensive key and at the same time flee from false triggering.This involves the design of various sages consisting of the pickup transducer, low frequency, audio low power and low noise amplifier, timer, bistable and switches. It also consists of special network components to prevent false triggering and ensure desired performance objectives. A decade counter IC serves the bistable function instead of flip-flop, special transistor and edge triggering network for low audio frequency.

  15. Resistance switching in silver - manganite contacts

    International Nuclear Information System (INIS)

    Gomez-Marlasca, F; Levy, P

    2009-01-01

    We investigate the electric pulse induced resistance switching in a transition metal oxide-metal contact at room temperature - a non volatile, reversible and multilevel memory device. Using a simple multiterminal configuration, we find that the complementary effect -in which the contact resistance of each pulsed electrode displays variations of opposite sign- is strongly influenced by the history of the pulsing procedure. Loops performed by varying the magnitude and sign of the stimulus at each pulsed electrode allow to disentangle their sole contribution at different stages of the process. Electromigration of oxygen ions and vacancies is discussed as participating at the core of the underlying mechanisms for resistance switching.

  16. Theory of circuit block switch-off

    Directory of Open Access Journals (Sweden)

    S. Henzler

    2004-01-01

    Full Text Available Switching-off unused circuit blocks is a promising approach to supress static leakage currents in ultra deep sub-micron CMOS digital systems. Basic performance parameters of Circuit Block Switch-Off (CBSO schemes are defined and their dependence on basic circuit parameters is estimated. Therefore the design trade-off between strong leakage suppression in idle mode and adequate dynamic performance in active mode can be supported by simple analytic investigations. Additionally, a guideline for the estimation of the minimum time for which a block deactivation is useful is derived.

  17. Resistance switching in silver - manganite contacts

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Marlasca, F [Materia Condensada GIA GAIANN CAC -CNEA, and Instituto de Nanociencia y Nanotecnologia, CNEA, Gral Paz 1499 (1650) San Martin, Pcia. Buenos Aires (Argentina); Levy, P, E-mail: levy@cnea.gov.a

    2009-05-01

    We investigate the electric pulse induced resistance switching in a transition metal oxide-metal contact at room temperature - a non volatile, reversible and multilevel memory device. Using a simple multiterminal configuration, we find that the complementary effect -in which the contact resistance of each pulsed electrode displays variations of opposite sign- is strongly influenced by the history of the pulsing procedure. Loops performed by varying the magnitude and sign of the stimulus at each pulsed electrode allow to disentangle their sole contribution at different stages of the process. Electromigration of oxygen ions and vacancies is discussed as participating at the core of the underlying mechanisms for resistance switching.

  18. Software Defined Networking (SDN) controlled all optical switching networks with multi-dimensional switching architecture

    Science.gov (United States)

    Zhao, Yongli; Ji, Yuefeng; Zhang, Jie; Li, Hui; Xiong, Qianjin; Qiu, Shaofeng

    2014-08-01

    Ultrahigh throughout capacity requirement is challenging the current optical switching nodes with the fast development of data center networks. Pbit/s level all optical switching networks need to be deployed soon, which will cause the high complexity of node architecture. How to control the future network and node equipment together will become a new problem. An enhanced Software Defined Networking (eSDN) control architecture is proposed in the paper, which consists of Provider NOX (P-NOX) and Node NOX (N-NOX). With the cooperation of P-NOX and N-NOX, the flexible control of the entire network can be achieved. All optical switching network testbed has been experimentally demonstrated with efficient control of enhanced Software Defined Networking (eSDN). Pbit/s level all optical switching nodes in the testbed are implemented based on multi-dimensional switching architecture, i.e. multi-level and multi-planar. Due to the space and cost limitation, each optical switching node is only equipped with four input line boxes and four output line boxes respectively. Experimental results are given to verify the performance of our proposed control and switching architecture.

  19. Task uncertainty can account for mixing and switch costs in task-switching.

    Directory of Open Access Journals (Sweden)

    Patrick S Cooper

    Full Text Available Cognitive control is required in situations that involve uncertainty or change, such as when resolving conflict, selecting responses and switching tasks. Recently, it has been suggested that cognitive control can be conceptualised as a mechanism which prioritises goal-relevant information to deal with uncertainty. This hypothesis has been supported using a paradigm that requires conflict resolution. In this study, we examine whether cognitive control during task switching is also consistent with this notion. We used information theory to quantify the level of uncertainty in different trial types during a cued task-switching paradigm. We test the hypothesis that differences in uncertainty between task repeat and task switch trials can account for typical behavioural effects in task-switching. Increasing uncertainty was associated with less efficient performance (i.e., slower and less accurate, particularly on switch trials and trials that afford little opportunity for advance preparation. Interestingly, both mixing and switch costs were associated with a common episodic control process. These results support the notion that cognitive control may be conceptualised as an information processor that serves to resolve uncertainty in the environment.

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

    Science.gov (United States)

    El-Sharkawi, Mohamed A.; Andexler, George; Silberkleit, Lee I.

    1993-01-19

    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).