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Sample records for cap toroid installation

  1. Last End Cap Toroid installation : The Pharaonic enterprise

    CERN Multimedia

    Arnaud Foussat

    After the successful and impressive transport feat from Building 191 to Point 1 was carried out by the Friderici crew on 28th June, the second and last Toroid End Cap, ECT-C, was transferred into the surface building, SX1, on 2nd July. The ECT-C was installed in the ATLAS cavern on the C-side on 12th July. As the person responsible for the project, in my opinion, one of the crucial points of this project was to design all the tooling and installation sequences taking into account the building infrastructure dimensional constraints. View of the ECT installation tooling and preparation for the ECT-C descent into the ATLAS 80m-shaft by the ATLAS magnet group and DBS teams. The movement of the 240-ton magnet and 12-m diameter toroid end-cap was achieved in collaboration with SCALES, a subcontractor company, using a hydraulic gantry able to lower the ECT inside the shaft by 5m below the floor level . This allowed the DBS team to attach the end-cap with the 2 x 140 tons overhead crane and lower it onto the c...

  2. Samus Toroid Installation Fixture

    Energy Technology Data Exchange (ETDEWEB)

    Stredde, H.; /Fermilab

    1990-06-27

    The SAMUS (Small Angle Muon System) toroids have been designed and fabricated in the USSR and delivered to D0 ready for installation into the D0 detector. These toroids will be installed into the aperture of the EF's (End Toroids). The aperture in the EF's is 72-inch vertically and 66-inch horizontally. The Samus toroid is 70-inch vertically by 64-inch horizontally by 66-inch long and weighs approximately 38 tons. The Samus toroid has a 20-inch by 20-inch aperture in the center and it is through this aperture that the lift fixture must fit. The toroid must be 'threaded' through the EF aperture. Further, the Samus toroid coils are wound about the vertical portion of the aperture and thus limit the area where a lift fixture can make contact and not damage the coils. The fixture is designed to lift along a surface adjacent to the coils, but with clearance to the coil and with contact to the upper steel block of the toroid. The lift and installation will be done with the 50 ton crane at DO. The fixture was tested by lifting the Samus Toroid 2-inch off the floor and holding the weight for 10 minutes. Deflection was as predicted by the design calculations. Enclosed are sketches of the fixture and it relation to both Toroids (Samus and EF), along with hand calculations and an Finite Element Analysis. The PEA work was done by Kay Weber of the Accelerator Engineering Department.

  3. ATLAS End Cap toroid in upstanding position

    CERN Multimedia

    2005-01-01

    End Cap toroid The ATLAS End Cap toroid weights 240-ton and is 12-m diameter high. The parts of this vacuum vessel had to be integrated and tested so that End Cap Toroid has no leaks. After that it could be cooled down to 80 K.

  4. Capping off installation

    CERN Multimedia

    2006-01-01

    Installation of the cathode strip chambers for the muon system on the CMS positive endcap has been completed. Technicians install one of the last muon system cathode strip chambers on the CMS positive endcap. Like successfully putting together the pieces of a giant puzzle, installation of the muon system cathode strip chambers on one of the CMS endcaps has been completed. Total installation of the cathode strip chambers (CSC) is now 91 percent complete; only one ring of chambers needs to be mounted on the remaining endcap to finish installation of the entire system. To guarantee a good fit for the 468 total endcap muon system CSCs, physicists and engineers from the collaboration spent about 10 years carefully planning the design. The endcap muon system's cables, boxes, pipes and other parts were designed and integrated using a 3D computerized model. 'It took a long time to do all the computer modelling, but in the long run it saved us an enormous amount of time because it meant that everything fit together,...

  5. ATLAS: End-cap Toroid assembly

    CERN Multimedia

    2006-01-01

    In building 191 and building 180- assembly of this massive piece.To reach the top of the end-cap the cranes has to be used and during the assembly you can see welding and hear many tools running background.

  6. First End Cap Toroid knocking on the door of SX1

    CERN Multimedia

    Herman Ten Kate

    On Tuesday May 29, the first Toroid End Cap for the A-side was transported from its test station next to B180 to the front of the ATLAS surface building SX1. The 240-ton and 12-m high toroid end-cap moved on a special trailer at walking speed, got over various slopes and survived the difficult turn left in front of the entrance at gate B. The toroid had to wait for almost two months to commence its journey to its destination as the cryogenic test down to 80K was already successfully completed by early April. In the next days, the toroid will slide into the SX1 building, turn around its axes by 90 degrees and then gently slide over the first shaft and land on top of the A-side shaft on Wednesday. There, it will descend by 5 m into the shaft using special lifting tooling before it can be connected to the 2x140 tons overhead cranes which will let the toroid go further down to the cavern. End Cap Toroid A on the trailer on its way to the cavern at Point 1. Crossing the main road near entrance A while t...

  7. The common cryogenic test facility for the ATLAS barrel and end-cap toroid magnets

    CERN Document Server

    Delruelle, N; Junker, S; Passardi, Giorgio; Pengo, R; Pirotte, O

    2004-01-01

    The large ATLAS toroidal superconducting magnet made of the Barrel and two End-Caps needs extensive testing at the surface of the individual components prior to their final assembly into the underground cavern of LHC. A cryogenic test facility specifically designed for cooling sequentially the eight coils making the Barrel Toroid (BT) has been fully commissioned and is now ready for final acceptance of these magnets. This facility, originally designed for testing individually the 46 tons BT coils, will be upgraded to allow the acceptance tests of the two End-Caps, each of them having 160 tons cold mass. The integrated system mainly comprises a 1.2 kW@4.5 K refrigerator, a 10 kW liquid-nitrogen precooler, two cryostats housing liquid helium centrifugal pumps of respectively 80 g/s and 600 g/s nominal flow and specific instrumentation to measure the thermal performances of the magnets. This paper describes the overall facility with particular emphasis to the cryogenic features adopted to match the specific requ...

  8. The Common Cryogenic Test Facility for the Atlas Barrel and End-Cap Toroid Magnet

    CERN Document Server

    Delruelle, N; Junker, S; Passardi, Giorgio; Pengo, R; Pirotte, O

    2004-01-01

    The large ATLAS toroidal superconducting magnet made of the Barrel and two End-Caps needs extensive testing at the surface of the individual components prior to their final assembly into the underground cavern of LHC. A cryogenic test facility specifically designed for cooling sequentially the eight coils making the Barrel Toroid (BT) has been fully commissioned and is now ready for final acceptance of these magnets. This facility, originally designed for testing individually the 46 tons BT coils, will be upgraded to allow the acceptance tests of the two End-Caps, each of them having a 160 tons cold mass. The integrated system mainly comprises a 1.2 kW@4.5 K refrigerator, a 10 kW liquid-nitrogen precooler, two cryostats housing liquid helium centrifugal pumps of respectively 80 g/s and 600 g/s nominal flow and specific instrumentation to measure the thermal performances of the magnets. This paper describes the overall facility with particular emphasis to the cryogenic features adopted to match the specific re...

  9. Installation of signal feedthroughs on an ATLAS liquid-argon calorimeter end-cap cryostat

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    The liquid-argon calorimeters used for hadronic energy measurements in the end-cap regions of the ATLAS detector are housed in cryostats to maintain the argon at the very low temperature required. The cryostats are equipped with signal feedthroughs, through which pass the electrical lines carrying signals from the calorimeters. Photos 01, 02, 03: Installation of the signal feedthroughs on the first of the two end-cap cryostats.

  10. Dutch supplier rewarded for manufacture of the two vacuum vessels for the ATLAS end-cap toroids

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    The ATLAS collaboration has presented an award for outstanding supplier performance to Dutch firm Schelde Exotech. Based on a design by Rutherford Appleton Laboratory, UK, Schelde Exotech manufactured under a NIKHEF contract the two 500 m3 large vacuum vessels for the cryostats of the ATLAS end-cap toroids. These 11-metre diameter castellated aluminium vessels with stainless-steel bore tube are essentially made up of 40-mm-thick plates for the shells, 75-mm-thick plates for the endplates, and 150-mm-thick bars for the flanges. Because of transport constraints, the vessels were made in halves, temporarily sealed and vacuum tested at the works, then transported to CERN for final assembly and acceptance tests. Both vessels were vacuum-tight and the meticulous and clean way of working ensured that a high vacuum was obtained within a few days of pumping. The delivery to CERN was completed in July 2002. Representatives of Schelde Exotech are seen here receiving their award in the ATLAS assembly hall. In the backgro...

  11. Installation of a Thomson scattering diagnostic on the Compact Toroidal Hybrid Experiment

    Science.gov (United States)

    Traverso, P. J.; Maurer, D. A.; Ennis, D. A.; Hartwell, G. J.; Cianciosa, M. R.

    2015-11-01

    A Thomson scattering system is being commissioned for the non-axisymmetric plasmas of the Compact Toroidal Hybrid (CTH), a five-field period current-carrying torsatron. The initial system takes a single point measurement on the magnetic axis and will be used to assess options for an expansion to a multi-point system to enable better 3D equilibrium reconstructions using the V3FIT code. A single point measurement will reduce the uncertainty in the reconstructed peak pressure by an order of magnitude for both current-carrying plasmas and future gyrotron-heated stellarator plasmas. The beam, generated by a frequency doubled Continuum 2 J, Nd:YaG laser, is passed vertically through an entrance Brewster window and a two-aperture optical baffle system to minimize stray light. The beam line is designed to propagate ~ 8 m to the mid-plane of the CTH device with the beam diameter < 3 mm inside the plasma volume. An Andor iStar DH740-18U-C3 image intensified CCD camera is used in conjunction with a Holospec f/1.8 spectrograph to collect the red-shifted scattered light from 532-580 nm. A single point system will initially measure plasmas with core electron temperatures of 100 to 200 eV and densities of 5 ×1018 to 5 ×1019 m-3. This work is supported by U.S. Department of Energy Grant No. DE-FG02-00ER54610.

  12. ATLAS End Cap Toroid

    CERN Multimedia

    CLRC-RAL

    1996-01-01

    Provisional assembly sequence June 1996. Real-time transcript fom SGI Onyx Reality Station. Design of assembly sequence by members of CME Group and Mechanical Design Group at RAL. Virtual reality and animation implementation by Virtual Systems Group at RAL.

  13. ATLAS end-caps 
on the move

    CERN Multimedia

    2007-01-01

    Two delicate and spectacular transport operations have been performed for ATLAS in recent weeks: the first end-cap tracker was installed in its final position, and one of the huge end-caps of the toroid magnet was moved to the top of the experiment’s shaft.

  14. Structure of a conserved hypothetical protein SA1388 from S. aureus reveals a capped hexameric toroid with two PII domain lids and a dinuclear metal center

    Directory of Open Access Journals (Sweden)

    Leybourne Matthew

    2006-12-01

    Full Text Available Abstract Background The protein encoded by the SA1388 gene from Staphylococcus aureus was chosen for structure determination to elucidate its domain organization and confirm our earlier remote homology based prediction that it housed a nitrogen regulatory PII protein-like domain. SA1388 was predicted to contain a central PII-like domain and two flanking regions, which together belong to the NIF3-like protein family. Proteins like SA1388 remain a poorly studied group and their structural characterization could guide future investigations aimed at understanding their function. Results The structure of SA1388 has been solved to 2.0Å resolution by single wavelength anomalous dispersion phasing method using selenium anomalous signals. It reveals a canonical NIF3-like fold containing two domains with a PII-like domain inserted in the middle of the polypeptide. The N and C terminal halves of the NIF3-like domains are involved in dimerization, while the PII domain forms trimeric contacts with symmetry related monomers. Overall, the NIF3-like domains of SA1388 are organized as a hexameric toroid similar to its homologs, E. coli ybgI and the hypothetical protein SP1609 from Streptococcus pneumoniae. The openings on either side of the toroid are partially covered by trimeric "lids" formed by the PII domains. The junction of the two NIF3 domains has two zinc ions bound at what appears to be a histidine rich active site. A well-defined electron density corresponding to an endogenously bound ligand of unknown identity is observed in close proximity to the metal site. Conclusion SA1388 is the third member of the NIF3-like family of proteins to be structurally characterized, the other two also being hypothetical proteins of unknown function. The structure of SA1388 confirms our earlier prediction that the inserted domain that separates the two NIF3 domains adopts a PII-like fold and reveals an overall capped toroidal arrangement for the protein hexamer. The

  15. Structure of a conserved hypothetical protein SA1388 from S. aureus reveals a capped hexameric toroid with two PII domain lids and a dinuclear metal center

    Energy Technology Data Exchange (ETDEWEB)

    Saikatendu, Kumar Singh; Zhang, Xuejun; Kinch, Lisa; Leybourne, Matthew; Grishin, Nick V.; Zhang, Hong (Texas-D); (U. of Texas-SMED)

    2009-01-26

    The protein encoded by the SA1388 gene from Staphylococcus aureus was chosen for structure determination to elucidate its domain organization and confirm our earlier remote homology based prediction that it housed a nitrogen regulatory PII protein-like domain. SA1388 was predicted to contain a central PII-like domain and two flanking regions, which together belong to the NIF3-like protein family. Proteins like SA1388 remain a poorly studied group and their structural characterization could guide future investigations aimed at understanding their function. The structure of SA1388 has been solved to 2.0{angstrom} resolution by single wavelength anomalous dispersion phasing method using selenium anomalous signals. It reveals a canonical NIF3-like fold containing two domains with a PII-like domain inserted in the middle of the polypeptide. The N and C terminal halves of the NIF3-like domains are involved in dimerization, while the PII domain forms trimeric contacts with symmetry related monomers. Overall, the NIF3-like domains of SA1388 are organized as a hexameric toroid similar to its homologs, E. coli ybgI and the hypothetical protein SP1609 from Streptococcus pneumoniae. The openings on either side of the toroid are partially covered by trimeric 'lids' formed by the PII domains. The junction of the two NIF3 domains has two zinc ions bound at what appears to be a histidine rich active site. A well-defined electron density corresponding to an endogenously bound ligand of unknown identity is observed in close proximity to the metal site. SA1388 is the third member of the NIF3-like family of proteins to be structurally characterized, the other two also being hypothetical proteins of unknown function. The structure of SA1388 confirms our earlier prediction that the inserted domain that separates the two NIF3 domains adopts a PII-like fold and reveals an overall capped toroidal arrangement for the protein hexamer. The six PII-like domains form two trimeric

  16. Toroid magnet test facility

    CERN Multimedia

    2002-01-01

    Because of its exceptional size, it was not feasible to assemble and test the Barrel Toroid - made of eight coils - as an integrated toroid on the surface, prior to its final installation underground in LHC interaction point 1. It was therefore decided to test these eight coils individually in a dedicated test facility.

  17. Quench Induced Pressure Rise in the Cooling Pipes of the Atlas Barrel Toroid Model

    CERN Document Server

    Haug, F; Broggi, F; Junker, S

    2004-01-01

    The ATLAS superconducting magnet system consists of a Barrel Toroid, two End-Cap Toroids and a Solenoid. Eight individual racetrack coils will be assembled to form the Barrel Toroid with overall dimensions of 26 m length and 20 m diameter. In order to verify the design concept a 9 m long short version of a single Barrel Toroid coil was built. A test program was conducted at the CERN cryogenic test facility which included the evaluation of the pressure rise in the helium cooling channels during quenches of the coil. A specific experimental set-up with cold pressure transducers and capillaries was installed for online measurement of the pressure signals. In addition a computer model was used to simulate these events. The data obtained are presented.

  18. Fast Dump of the ATLAS Toroids

    CERN Document Server

    Dudarev, A; Volpini, Giovanni; Dudarev, Alexey; Kate, Herman Ten

    2010-01-01

    The toroidal magnet system of the ATLAS Detector at CERN consists of a Barrel Toroid (BT) and two End Cap Toroids (ECT-A and ECT-C). Each toroid is built up from eight racetrack coils wound with an aluminum stabilized NbTi conductor and indirectly cooled by forced flow liquid helium. The three toroids operate in series at 20.5 kA with a total stored energy of 1.5 GJ. In order to verify the reliability and effectiveness of the quench protection system, series of fast dump tests have been performed first of the single toroids and finally of the entire toroidal magnet system. In this paper a model to simulate the fast dump of the ATLAS toroids in single mode operation and in full system configuration is presented. The model is validated through comparison with measured data extracted from the ramp-and-quench runs. The calculated energy dissipation in the various coils is in very good agreement (within 1-2\\%) with the enthalpy changes estimated from the temperature measurements of the different parts of the cold ...

  19. Sensing with toroidal metamaterial

    Science.gov (United States)

    Gupta, Manoj; Srivastava, Yogesh Kumar; Manjappa, Manukumara; Singh, Ranjan

    2017-03-01

    Localized electromagnetic excitation in the form of toroidal dipoles has recently been observed in metamaterial systems. The origin of the toroidal dipole lies in the currents flowing on the surface of a torus. Thus, the exotic toroidal excitations play an important role in determining the optical properties of a system. Toroidal dipoles also contribute towards enabling high quality factor subwavelength resonances in metamaterial systems which could be an excellent platform for probing the light matter interaction. Here, we demonstrate sensing with toroidal resonance in a two-dimensional terahertz metamaterial in which a pair of mirrored asymmetric Fano resonators possesses anti-aligned magnetic moments at an electromagnetic resonance that gives rise to a toroidal dipole. Our proof of concept demonstration opens up an avenue to explore the interaction of matter with toroidal multipoles that could have strong applications in the sensing of dielectrics and biomolecules.

  20. First full-size ATLAS barrel toroid coil successfully tested up to 22 kA at 4 T

    CERN Document Server

    Dudarev, A; Benoit, P; Berriaud, C P; Broggi, F; Deront, L; Foussat, A; Junker, S; ten Kate, H H J; Kopeykin, N; Olesen, G; Olyunin, A; Pengo, R; Rabbers, J J; Ravat, S; Rey, J M; Sbrissa, E; Shugaev, I; Stepanov, V; Védrine, P; Volpini, Giovanni

    2005-01-01

    The Superconducting Barrel Toroid is providing (together with the two End-Cap Toroids not presented here) the magnetic field for the muon detectors in the ATLAS Experiment at the LHC at CERN. The toroid with outer dimensions of 25 m length and 20 m diameter, is built up from 8 identical racetrack coils. The coils with 120 turns each are wound with an aluminum stabilized NbTi conductor and operate at 20.5 kA at 3.9 T local field in the windings and is conduction cooled at 4.8 K by circulating forced flow helium in cooling tubes attached to the cold mass. The 8 coils of 25 m * 5 m are presently under construction and the first coils have already been fully integrated and tested. Meanwhile the assembly of the toroid 100 m underground in the ATLAS cavern at CERN has started. The 8 coils are individually tested on surface before installation. In this paper the test of the first coil, unique in size and manufacturing technology, is described in detail and the results are compared to the previous experience with the...

  1. Quench propagation and protection analysis of the ATLAS Toroids

    CERN Document Server

    Dudarev, A; ten Kate, H H J; Baynham, D Elwyn; Courthold, M J D; Lesmond, C

    2000-01-01

    The ATLAS superconducting magnet system consists of the Barrel Toroid, two End Cap Toroids and the Central Solenoid. However, the Toroids of eight coils each are magnetically separate systems to the Central Solenoid. The Toroids are electrically connected in series and energized by a single power supply. The quench protection system is based on the use of relatively small external dump resistances in combination with quench-heaters activated after a quench event detection to initiate the internal dump of stored energy in all the coils. A rather strong quench-back effect due to eddy-currents in the coil casings at the transport current decay is beneficial for the quench protection efficiency in the event of heater failures. The quench behaviour of the ATLAS Toroids was computer simulated for normal operation of the quench protection system and its complete non-operation (failure) mode. (3 refs).

  2. New Toroid shielding design

    CERN Multimedia

    Hedberg V

    On the 15th of June 2001 the EB approved a new conceptual design for the toroid shield. In the old design, shown in the left part of the figure above, the moderator part of the shielding (JTV) was situated both in the warm and cold areas of the forward toroid. It consisted both of rings of polyethylene and hundreds of blocks of polyethylene (or an epoxy resin) inside the toroid vacuum vessel. In the new design, shown to the right in the figure above, only the rings remain inside the toroid. To compensate for the loss of moderator in the toroid, the copper plug (JTT) has been reduced in radius so that a layer of borated polyethylene can be placed around it (see figure below). The new design gives significant cost-savings and is easier to produce in the tight time schedule of the forward toroid. Since the amount of copper is reduced the weight that has to be carried by the toroid is also reduced. Outgassing into the toroid vacuum was a potential problem in the old design and this is now avoided. The main ...

  3. Toroidal optical activity

    CERN Document Server

    Raybould, T A; Papasimakis, N; Kuprov, I; Youngs, I; Chen, W T; Tsai, D P; Zheludev, N I

    2015-01-01

    Optical activity is ubiquitous across natural and artificial media and is conventionally understood in terms of scattering from electric and magnetic moments. Here we demonstrate experimentally and confirm numerically a type of optical activity that cannot be attributed to electric and magnetic multipoles. We show that our observations can only be accounted for by the inclusion of the toroidal dipole moment, the first term of the recently established peculiar family of toroidal multipoles.

  4. Progress in Compact Toroid Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Dolan, Thomas James

    2002-09-01

    The term "compact toroids" as used here means spherical tokamaks, spheromaks, and field reversed configurations, but not reversed field pinches. There are about 17 compact toroid experiments under construction or operating, with approximate parameters listed in Table 1.

  5. 圆环坐标系下自供能转换器球冠型拓扑的建模与优化%Modeling and Optimization of Spherical Cap Topology for Energy Scavenging Converters in Toroidal Coordinate Space

    Institute of Scientific and Technical Information of China (English)

    黄金鑫; 张黎; 于春辉; 李庆民; Martin D.Judd; W.H.Siew

    2012-01-01

    电容式集能转换器的设计和优化直接影响自供能装置的整体性能.集能效率的优化可转化为体积约束条件下的拓扑参数优化,由此提出一种改进的球冠型集能转换器拓扑,并在圆环坐标系下基于分离变量法建立了其解析模型.提出储能增量系数的概念,并导出以球冠开口半径与球半径之比为变量的储能增量系数表达式.针对不同尺寸的球冠型拓扑,储能增量系数的实测结果与理论值吻合地较好,从而验证了所建立的球冠型转换器拓扑解析模型的正确性.研究结果为自供能装置集能转换器的优化设计提供了理论依据.%The topology design and optimization of the capacitive energy scavenging converter will directly determine the performance of the whole device. The optimization of the energy harvesting efficiency could be translated into optimization of the topology parameters under volume restriction. An improved converter topology with the spherical cap was proposed, and the corresponding analytical model was further established based on the method of the separation of variables within the toridal coordinate system. The concept of the energy increment factor was defined and the numerical expression was presented in term of the spherical cap radius. With regards to the spherical cap converter topology of different dimensions, the measured values of energy increment factor coincided well with their theoretical equivalents, which effectively verified the validity of the proposed analytical model for the spherical cap converter topology. The research results present the theoretical basis for optimal design of the energy scavenging devices.

  6. The CERN Cryogenic Test Facility for the Atlas Barrel Toroid Magnets

    CERN Document Server

    Haug, F; Delruelle, N; Orlic, J P; Passardi, Giorgio; Tischhauser, Johann

    1999-01-01

    The superconducting magnet system of the ATLAS detector will consist of a central solenoid, two end-cap toroidal magnets (ECT) and the barrel toroid magnet (BT) made of eight coils symmetrically placed around the central axis of the detector. The magnets will be tested individually in a 5000 m2 experimental area prior to their final installation at an underground cavern of the LHC Collider. For the BT magnets, a dedicated cryogenic test facility has been designed which is currently under the construction and commissioning phase. A liquid nitrogen pre-cooling unit and a 1200 W@4.5K refrigerator will allow flexible operating conditions via a rather complex distribution and transfer line system. Flow of two-phase helium for cooling the coils is provided by centrifugal pumps immersed in a saturated liquid helium bath. The integration of the pumps in an existing cryostat required the adoption of novel mechanical solutions. Tests conducted permitted the validation of the technical design of the cryostat and its ins...

  7. The CERN cryogenic test facility for the ATLAS barrel toroid magnets

    CERN Document Server

    Haug, F; Delruelle, N; Orlic, J P; Passardi, Giorgio; Tischhauser, Johann

    2000-01-01

    The superconducting magnet system of the ATLAS detector will consist of a central solenoid, two end-cap toroidal magnets (ECT) and the barrel toroid magnet (BT) made of eight coils symmetrically placed around the central axis of the detector. The magnets will be tested individually in a 5000 m/sup 2/ experimental area prior to their final installation at an underground cavern of the LHC Collider. For the BT magnets, a dedicated cryogenic test facility has been designed which is currently under the construction and commissioning phase. A liquid nitrogen pre-cooling unit and a 1200 W@4.5K refrigerator will allow flexible operating conditions via a rather complex distribution and transfer line system. Flow of two-phase helium for cooling the coils is provided by centrifugal pumps immersed in a saturated liquid helium bath. The integration of the pumps in an existing cryostat required the adoption of novel mechanical solutions. Tests conducted permitted the validation of the technical design of the cryostat and i...

  8. On the dynamic toroidal multipoles

    CERN Document Server

    Fernandez-Corbaton, Ivan; Rockstuhl, Carsten

    2015-01-01

    Toroidal multipoles are attracting research attention, particularly in the field of metamaterials. They are often understood as a multipolar family in its own right. The dynamic toroidal multipoles emerge from the separation of one of the two transverse multipoles into two parts, referred to as electric and toroidal. Here, we establish that the dynamic toroidal multipolar components of an electric current distribution cannot be determined by measuring the radiation from the source or its coupling to external electromagnetic waves. We analytically show how the split into electric and toroidal parts causes the appearance of non-radiative components in each of the two parts, which cancel when summed back together. The toroidal multipoles do not have an independent meaning with respect to their interaction with the radiation field. Their formal meaning is clear, however. They are the higher order terms of an expansion of the multipolar coefficients of electric parity with respect to the electromagnetic size of th...

  9. Axion Haloscopes with Toroidal Geometry at CAPP/IBS

    CERN Document Server

    Ko, B R

    2016-01-01

    The present state of the art axion haloscope employs a cylindrical resonant cavity in a solenoidal field. We, the Center for Axion and Precision Physics Research (CAPP) of the Institute for Basic Science (IBS) in Korea, are also pursuing halo axion discovery using this cylindrical geometry. However, the presence of end caps of cavities increases challenges as we explore higher frequency regions for the axion at above 2 GHz. To overcome these challenges we exploit a toroidal design of cavity and magnetic field. A toroidal geometry offers several advantages, two of which are a larger volume for a given space and greatly reduced fringe fields which interfere with our preamps, in particular the planned quantum-based devices. We introduce the concept of toroidal axion haloscopes and present ongoing research activities and plans at CAPP/IBS.

  10. On the Toroidal Leibniz Algebras

    Institute of Scientific and Technical Information of China (English)

    Dong LIU; Lei LIN

    2008-01-01

    Toroidal Leibniz algebras are the universal central extensions of the iterated loop algebras gOC[t±11 ,...,t±v1] in the category of Leibniz algebras. In this paper, some properties and representations of toroidal Leibniz algebras are studied. Some general theories of central extensions of Leibniz algebras are also obtained.

  11. Profiling compact toroid plasma density on CTIX with laser deflection

    Science.gov (United States)

    Brockington, Samuel Joseph Erwin

    A laser deflectometer measures line-integrated plasma density gradient using laser diodes and amplified point detectors. A laser passing through an optically thin plasma is refracted by an amount proportional to the line-integrated electron density gradient. I have designed, installed, and operated a deflection diagnostic for the Compact Toroid Injection Experiment (CTIX), a plasma rail gun which can create compact toroid (CT) plasmas of controllable density and velocity. The diagnostic design and motivation are discussed, as well as three experiments performed with deflectometry. Thus, my thesis consists of the design of the deflectometer diagnostic, a comparison of its accuracy to interferometer density measurements, and finally a survey of compact toroid density profiles in two dimensions conducted with an array of detectors.

  12. Next generation toroidal devices

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, Shoichi [Princeton Plasma Physics Lab., Princeton Univ., NJ (United States)

    1998-10-01

    A general survey of the possible approach for the next generation toroidal devices was made. Either surprisingly or obviously (depending on one`s view), the technical constraints along with the scientific considerations lead to a fairly limited set of systems for the most favorable approach for the next generation devices. Specifically if the magnetic field strength of 5 T or above is to be created by superconducting coils, it imposes minimum in the aspect ratio for the tokamak which is slightly higher than contemplated now for ITER design. The similar technical constraints make the minimum linear size of a stellarator large. Scientifically, it is indicated that a tokamak of 1.5 times in the linear dimension should be able to produce economically, especially if a hybrid reactor is allowed. For the next stellarator, it is strongly suggested that some kind of helical axis is necessary both for the (almost) absolute confinement of high energy particles and high stability and equilibrium beta limits. The author still favors a heliac most. Although it may not have been clearly stated in the main text, the stability afforded by the shearless layer may be exploited fully in a stellarator. (author)

  13. The Superconducting Toroid for the New International AXion Observatory (IAXO)

    CERN Document Server

    Shilon, I; Silva, H; Wagner, U; Kate, H H J ten

    2013-01-01

    IAXO, the new International AXion Observatory, will feature the most ambitious detector for solar axions to date. Axions are hypothetical particles which were postulated to solve one of the puzzles arising in the standard model of particle physics, namely the strong CP (Charge conjugation and Parity) problem. This detector aims at achieving a sensitivity to the coupling between axions and photons of one order of magnitude beyond the limits of the current detector, the CERN Axion Solar Telescope (CAST). The IAXO detector relies on a high-magnetic field distributed over a very large volume to convert solar axions to detectable X-ray photons. Inspired by the ATLAS barrel and end-cap toroids, a large superconducting toroid is being designed. The toroid comprises eight, one meter wide and twenty one meters long racetrack coils. The assembled toroid is sized 5.2 m in diameter and 25 m in length and its mass is about 250 tons. The useful field in the bores is 2.5 T while the peak magnetic field in the windings is 5....

  14. RF breakdown by toroidal helicons

    Indian Academy of Sciences (India)

    S K P Tripathi; D Bora; M Mishra

    2001-04-01

    Bounded whistlers are well-known for their efficient plasma production capabilities in thin cylindrical tubes. In this paper we shall present their radio frequency (RF) breakdown and discharge sustaining capabilities in toroidal systems. Pulsed RF power in the electronmagnetohydrodynamic (EMHD) frequency regime is fed to the neutral background medium. After the breakdown stage, discharge is sustained by toroidal bounded whistlers. In these pulsed experiments the behaviour of the time evolution of the discharge could be studied in four distinct phases of RF breakdown, steady state attainment, decay and afterglow. In the steady state average electron density of ≈ 1012 per cc and average electron temperature of ≈ 20 eV are obtained at 10-3 mbar of argon filling pressure. Experimental results on toroidal mode structure, background effects and time evolution of the electron distribution function will be presented and their implications in understanding the breakdown mechanism are discussed.

  15. Prandtl number of toroidal plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Kimitaka (National Inst. for Fusion Science, Nagoya (Japan)); Itoh, Sanae; Fukuyama, Atsushi; Yagi, Masatoshi; Azumi, Masafumi

    1993-12-01

    Theory of the L-mode confinement in toroidal plasmas is developed. The Prandtl number, the ratio between the ion viscosity and the thermal conductivity is obtained for the anomalous transport process which is caused by the self-sustained turbulence in the toroidal plasma. It is found that the Prandtl number is of order unity both for the ballooning mode turbulence in tokamaks and for the interchange mode turbulence in helical system. The influence on the anomalous transport and fluctuation level is evaluated. Hartmann number and magnetic Prandtl number are also discussed. (author).

  16. Hybrid winding concept for toroids

    DEFF Research Database (Denmark)

    Schneider, Henrik; Andersen, Thomas; Knott, Arnold;

    2013-01-01

    This paper proposes a hybrid winding concept for toroids using the traces in a printed circuit board to make connection to bended copper foil cutouts. In a final product a number of strips with a certain thickness would be held by a former and the whole assembly could be placed by pick...... and placement machinery. This opens up the possibility for both an automated manufacturing process and an automated production process of toroidal magnetics such as power inductors, filtering inductors, air core inductors, transformers etc. Both the proposed hybrid and the common wire wound winding...

  17. The complex and unique ATLAS Toroid family

    CERN Multimedia

    2002-01-01

    Big parts for the toroid magnets that will be used in the ATLAS experiment have been continuously arriving at CERN since March. These structures will create the largest superconducting toroid magnet ever.

  18. Hybrid winding concept for toroids

    DEFF Research Database (Denmark)

    Schneider, Henrik; Andersen, Thomas; Knott, Arnold;

    2013-01-01

    This paper proposes a hybrid winding concept for toroids using the traces in a printed circuit board to make connection to bended copper foil cutouts. In a final product a number of strips with a certain thickness would be held by a former and the whole assembly could be placed by pick and placem...

  19. Onsager relaxation of toroidal plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Samain, A.; Nguyen, F.

    1997-01-01

    The slow relaxation of isolated toroidal plasmas towards their thermodynamical equilibrium is studied in an Onsager framework based on the entropy metric. The basic tool is a variational principle, equivalent to the kinetic equation, involving the profiles of density, temperature, electric potential, electric current. New minimization procedures are proposed to obtain entropy and entropy production rate functionals. (author). 36 refs.

  20. Extremely high Q-factor toroidal metamaterials

    CERN Document Server

    Basharin, Alexey A; Volsky, Nikita; Kafesaki, Maria; Economou, Eleftherios N; Ustinov, Alexey V

    2016-01-01

    We demonstrate that, owing to the unique topology of the toroidal dipolar mode, its electric/magnetic field can be spatially confined within subwavelength, externally accessible regions of the metamolecules, which makes the toroidal planar metamaterials a viable platform for high Q-factor resonators due to interfering toroidal and other dipolar modes in metamolecules.

  1. Intrinsic rotation of toroidally confined magnetohydrodynamics.

    Science.gov (United States)

    Morales, Jorge A; Bos, Wouter J T; Schneider, Kai; Montgomery, David C

    2012-10-26

    The spatiotemporal self-organization of viscoresistive magnetohydrodynamics in a toroidal geometry is studied. Curl-free toroidal magnetic and electric fields are imposed. It is observed in our simulations that a flow is generated, which evolves from dominantly poloidal to toroidal when the Lundquist numbers are increased. It is shown that this toroidal organization of the flow is consistent with the tendency of the velocity field to align with the magnetic field. Up-down asymmetry of the geometry causes the generation of a nonzero toroidal angular momentum.

  2. Design and Simulation of Toroidal Twister Model

    Institute of Scientific and Technical Information of China (English)

    TIAN Huifang; LIN Xizhen; ZENG Qinqin

    2006-01-01

    Toroidal composite vessel winded with fiber is a new kind of structural pressure vessels, which not only has high structure efficiency of compound materials pressure vessel, good security and so on, but also has special shape and the property of utilizing toroidal space, and the prospect of the application of toroidal composite vessel winded with fiber is extremely broad. By introducing parameters establishment of toroidal vessel and elaborating the principle of filament winding for toroidal vessel, the design model of filament winding machine for toroidal vessel has been introduced, and the design model has been dynamically simulated by the software of ADAMS, which will give more referrence for the design of real toroidal vessel twister.

  3. Classification of symmetric toroidal orbifolds

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Maximilian; Ratz, Michael; Torrado, Jesus [Technische Univ. Muenchen, Garching (Germany). Physik-Department; Vaudrevange, Patrick K.S. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2012-09-15

    We provide a complete classification of six-dimensional symmetric toroidal orbifolds which yield N{>=}1 supersymmetry in 4D for the heterotic string. Our strategy is based on a classification of crystallographic space groups in six dimensions. We find in total 520 inequivalent toroidal orbifolds, 162 of them with Abelian point groups such as Z{sub 3}, Z{sub 4}, Z{sub 6}-I etc. and 358 with non-Abelian point groups such as S{sub 3}, D{sub 4}, A{sub 4} etc. We also briefly explore the properties of some orbifolds with Abelian point groups and N=1, i.e. specify the Hodge numbers and comment on the possible mechanisms (local or non-local) of gauge symmetry breaking.

  4. Transporting the first ATLAS toroid

    CERN Multimedia

    Maximilien Brice

    2004-01-01

    The first coil for the ATLAS toroid magnet is transported from its assembly hall at the CERN Meyrin site to the storage hall above the ATLAS cavern. This involves driving the massive transportation vehicle first through the Meyrin site and then across a main road only metres from the France-Swiss border. Eight magnets in total will be transported in this way before being lowered into the experimental cavern where they will be mounted in a huge ring surrounding the detector.

  5. Half of one of the end-cap magnet vacuum vessels passing through Gex on its way to CERN.

    CERN Multimedia

    Maximilien Brice

    2002-01-01

    More large pieces of the ATLAS detector arrived recently at CERN. The trailer seen here carries the vacuum vessel for one half of the toroid magnet that will form one of the end-caps of the complete detector.

  6. Magnetic Properties of 3D Printed Toroids

    Science.gov (United States)

    Bollig, Lindsey; Otto, Austin; Hilpisch, Peter; Mowry, Greg; Nelson-Cheeseman, Brittany; Renewable Energy; Alternatives Lab (REAL) Team

    Transformers are ubiquitous in electronics today. Although toroidal geometries perform most efficiently, transformers are traditionally made with rectangular cross-sections due to the lower manufacturing costs. Additive manufacturing techniques (3D printing) can easily achieve toroidal geometries by building up a part through a series of 2D layers. To get strong magnetic properties in a 3D printed transformer, a composite filament is used containing Fe dispersed in a polymer matrix. How the resulting 3D printed toroid responds to a magnetic field depends on two structural factors of the printed 2D layers: fill factor (planar density) and fill pattern. In this work, we investigate how the fill factor and fill pattern affect the magnetic properties of 3D printed toroids. The magnetic properties of the printed toroids are measured by a custom circuit that produces a hysteresis loop for each toroid. Toroids with various fill factors and fill patterns are compared to determine how these two factors can affect the magnetic field the toroid can produce. These 3D printed toroids can be used for numerous applications in order to increase the efficiency of transformers by making it possible for manufacturers to make a toroidal geometry.

  7. Death cap

    DEFF Research Database (Denmark)

    Rudbæk, Torsten R; Kofoed, Pernille Bouteloup; Bove, Jeppe

    2014-01-01

    Death cap (Amanita phalloides) is commonly found and is one of the five most toxic fungi in Denmark. Toxicity is due to amatoxin, and poisoning is a serious medical condition, causing organ failure with potential fatal outcome. Acknowledgement and clarification of exposure, symptomatic and focused...

  8. Beam Transport in Toroidal Magnetic Field

    CERN Document Server

    Joshi, N; Meusel, O; Ratzinger, U

    2016-01-01

    The concept of a storage ring with toroidal magnetic field was presented in the two previous EPAC conferences. Here we report the first results of experiments performed with beam transport in toroidal magnetic fields and details of the injection system. The beam transport experiments were carried out with 30 degree toroidal segments with an axial magnetic field of 0.6T. The multi turn injection system relies on a transverse injection coil together with an electric kicker system.

  9. Apical cap

    Energy Technology Data Exchange (ETDEWEB)

    McLoud, T.C.; Isler, R.J.; Novelline, R.A.; Putman, C.E.; Simeone, J.; Stark, P.

    1981-08-01

    Apical caps, either unilateral or bilateral, are a common feature of advancing age and are usually the result of subpleural scarring unassociated with other diseases. Pancoast (superior sulcus) tumors are a well recognized cause of unilateral asymmetric apical density. Other lesions arising in the lung, pleura, or extrapleural space may produce unilateral or bilateral apical caps. These include: (1) inflammatory: tuberculosis and extrapleural abscesses extending from the neck; (2) post radiation fibrosis after mantle therapy for Hodgkin disease or supraclavicular radiation in the treatment of breast carcinoma; (3) neoplasm: lymphoma extending from the neck or mediastinum, superior sulcus bronchogenic carcinoma, and metastases; (4) traumatic: extrapleural dissection of blood from a ruptured aorta, fractures of the ribs or spine, or hemorrhage due to subclavian line placement; (5) vascular: coarctation of the aorta with dilated collaterals over the apex, fistula between the subclavian artery and vein; and (6) miscellaneous: mediastinal lipomatosis with subcostal fat extending over the apices.

  10. Mammalian CAP interacts with CAP, CAP2, and actin.

    Science.gov (United States)

    Hubberstey, A; Yu, G; Loewith, R; Lakusta, C; Young, D

    1996-06-01

    We previously identified human CAP, a homolog of the yeast adenylyl cyclase-associated protein. Previous studies suggest that the N-terminal and C-terminal domains of CAP have distinct functions. We have explored the interactions of human CAP with various proteins. First, by performing yeast two-hybrid screens, we have identified peptides from several proteins that interact with the C-terminal and/or the N-terminal domains of human CAP. These peptides include regions derived from CAP and BAT3, a protein with unknown function. We have further shown that MBP fusions with these peptides can associate in vitro with the N-terminal or C-terminal domains of CAP fused to GST. Our observations indicate that CAP contains regions in both the N-terminal and C-terminal domains that are capable of interacting with each other or with themselves. Furthermore, we found that myc-epitope-tagged CAP coimmunoprecipitates with HA-epitope-tagged CAP from either yeast or mammalian cell extracts. Similar results demonstrate that human CAP can also interact with human CAP2. We also show that human CAP interacts with actin, both by the yeast two-hybrid test and by coimmunoprecipitation of epitope-tagged CAP from yeast or mammalian cell extracts. This interaction requires the C-terminal domain of CAP, but not the N-terminal domain. Thus CAP appears to be capable of interacting in vivo with other CAP molecules, CAP2, and actin. We also show that actin co-immunoprecipitates with HA-CAP2 from mammalian cell extracts.

  11. Electrostatics of a Family of Conducting Toroids

    Science.gov (United States)

    Lekner, John

    2009-01-01

    An exact solution is found for the electrostatic potential of a family of conducting charged toroids. The toroids are characterized by two lengths "a" and "b", with "a" greater than or equal to "2b". They are closed, with no hole in the "doughnut". The results are obtained by considering the potential of two equal charges, displaced from the…

  12. Toroidal effects on drift wave turbulence

    Energy Technology Data Exchange (ETDEWEB)

    LeBrun, M.J.; Tajima, T.; Gray, M.G.; Furnish, G.; Horton, W.

    1992-09-23

    The universal drift instability and other drift instabilities driven by density and temperature gradients in a toroidal system are investigated in both linear and nonlinear regimes via particle simulation. Runs in toroidal and cylindrical geometry show dramatic differences in plasma behavior, primarily due to the toroidicity-induced coupling of rational surfaces through the poloidal mode number m. In the toroidal system studied, the eigenmodes are seen to possess (i) an elongated, nearly global radial extent (ii) a higher growth rate than in the corresponding cylindrical system, (iii) an eigenfrequency nearly constant with radius, (iv) a global temperature relaxation and enhancement of thermal heat conduction. Most importantly, the measured Xi shows an increase with radius and an absolute value on the order of that observed in experiment. On the basis of our observations, we argue that the increase in Xi with radius observed in experiment is caused by the global nature of heat convection in the presence of toroidicity-induced mode coupling.

  13. CNGS Reflector installed

    CERN Multimedia

    2006-01-01

    A major component that will help target the CNGS neutrino beam for its 732km journey through the earth's crust, from CERN to the Gran Sasso laboratory in Italy, has been installed in its final position. The transport of the huge magnetic horn reflector through the CNGS access gallery. A team from CNGS and TS/IC, and the contractors DBS, transported the magnetic horn reflector on 5th December, in a carefully conducted operation that took just under two hours. The reflector is 7m long, 1.6m in diameter and 1.6 tonnes in weight. With only a matter of centimetres to spare on either side, the reflector was transported through the CNGS access gallery, before being installed in the experiment's target chamber. The larger of two magnetic horns, the reflector will help refocus sprays of high energy pions and kaons emitted after a 0.5MW stream of protons from the Super Proton Synchrotron (SPS) strikes nucleons in a graphite target. The horns are toroidal magnetic lenses and work with high pulsed currents: 150 kA f...

  14. Development of Toroidal Core Transformers

    Energy Technology Data Exchange (ETDEWEB)

    de Leon, Francisco [New York Univ. (NYU), Brooklyn, NY (United States). Dept. of Electrical and Computer Engineering

    2014-08-01

    The original objective of this project was to design, build and test a few prototypes of single-phase dry-type distribution transformers of 25 kVA, 2.4 kV primary to 120 V transformers using cores made of a continuous steel strip shaped like a doughnut (toroid). At different points during the development of the project, the scope was enhanced to include the more practical case of a 25 kVA transformer for a 13.8 kV primary system voltage. Later, the scope was further expanded to design and build a 50 kVA unit to transformer voltage from 7.62 kV to 2x120 V. This is a common transformer used by Con Edison of New York and they are willing to test it in the field. The project officially started in September 2009 and ended in May 2014. The progress was reported periodically to DOE in eighteen quarterly reports. A Continuation Application was submitted to DOE in June 2010. In May 2011 we have requested a non-cost extension of the project. In December 2011, the Statement of Project Objectives (SOPO) was updated to reflect the real conditions and situation of the project as of 2011. A second Continuation Application was made and funding was approved in 2013 by DOE and the end date was extended to May 2014. The technical challenges that were overcome in this project include: the development of the technology to pass the impulse tests, derive a model for the thermal performance, produce a sound mechanical design, and estimate the inrush current. However, the greatest challenge that we faced during the development of the project was the complications of procuring the necessary parts and materials to build the transformers. The actual manufacturing process is relatively fast, but getting all parts together is a very lengthy process. The main products of this project are two prototypes of toroidal distribution transformers of 7.62 kV (to be used in a 13.8 kV system) to 2x120 V secondary (standard utilization voltage); one is rated at 25 kVA and the other at 50 kVA. The 25 k

  15. Development of Toroidal Core Transformers

    Energy Technology Data Exchange (ETDEWEB)

    Leon, Francisco

    2014-05-31

    The original objective of this project was to design, build and test a few prototypes of singlephase dry-type distribution transformers of 25 kVA, 2.4 kV primary to 120 V transformers using cores made of a continuous steel strip shaped like a doughnut (toroid). At different points during the development of the project, the scope was enhanced to include the more practical case of a 25 kVA transformer for a 13.8 kV primary system voltage. Later, the scope was further expanded to design and build a 50 kVA unit to transformer voltage from 7.62 kV to 2x120 V. This is a common transformer used by Con Edison of New York and they are willing to test it in the field. The project officially started in September 2009 and ended in May 2014. The progress was reported periodically to DOE in eighteen quarterly reports. A Continuation Application was submitted to DOE in June 2010. In May 2011 we have requested a non-cost extension of the project. In December 2011, the Statement of Project Objectives (SOPO) was updated to reflect the real conditions and situation of the project as of 2011. A second Continuation Application was made and funding was approved in 2013 by DOE and the end date was extended to May 2014.The technical challenges that were overcome in this project include: the development of the technology to pass the impulse tests, derive a model for the thermal performance, produce a sound mechanical design, and estimate the inrush current. However, the greatest challenge that we faced during the development of the project was the complications of procuring the necessary parts and materials to build the transformers. The actual manufacturing process is relatively fast, but getting all parts together is a very lengthy process. The main products of this project are two prototypes of toroidal distribution transformers of 7.62 kV (to be used in a 13.8 kV system) to 2x120 V secondary (standard utilization voltage); one is rated at 25 kVA and the other at 50 kVA. The 25 k

  16. Installing Omeka

    Directory of Open Access Journals (Sweden)

    Jonathan Reeve

    2016-07-01

    Full Text Available Omeka.net is a useful service for Omeka beginners, but there are a few reasons why you might want to install your own copy of Omeka. Reasons include: * Upgrades. By installing Omeka yourself, you can use the latest versions of Omeka as soon as they’re released, without having to wait for Omeka.net to upgrade their system. * Plugins and themes. You can install any plugin or theme you want, without being restricted to those provided by Omeka.net. * Customizations. You can buy a custom domain name, and customize your code to achieve your desired functionality. * Control. You have control over your own backups, and you can update the server yourself so that its security is always up-to-date. * Price. There are many low-cost Virtual Private Servers (VPSs now, some of which cost only $5 per month. * Storage. Many shared hosting providers now offer unlimited storage. This is useful if you have a large media library. In this tutorial, we’ll be entering a few commands on the command line. This tutorial assumes no prior knowledge of the command line, but if you want a concise primer, consult the Programming Historian introduction to BASH. There are other ways of installing Omeka, of course, some using exclusively GUI tools. Some hosting providers even offer “one-click installs” via their control panels. Many of those methods, however, will install older versions of Omeka which are then harder to upgrade and maintain. The method outlined below may not be the easiest way to install Omeka, but it will give you some good practice with using the command line, which is a skill that will be useful if you want to manually upgrade your install, or manually install other web frameworks. (For example, this installation method is very similar to WordPress’s “Five-Minute Install”. There are four steps to this process, and it should take about an hour.

  17. Tokamak with in situ magnetohydrodynamic generation of toroidal magnetic field

    Science.gov (United States)

    Schaffer, Michael J.

    1986-01-01

    A tokamak apparatus includes an electrically conductive metal pressure vessel for defining a chamber and confining liquid therein. A liner disposed within said chamber defines a toroidal space within the liner and confines gas therein. The metal vessel provides an electrically conductive path linking the toroidal space. Liquid metal is forced outwardly through the chamber outside of the toroidal space to generate electric current in the conductive path and thereby generate a toroidal magnetic field within the toroidal space. Toroidal plasma is developed within the toroidal space about the major axis thereof.

  18. Toroidal horizons in binary black hole mergers

    Science.gov (United States)

    Bohn, Andy; Kidder, Lawrence E.; Teukolsky, Saul A.

    2016-09-01

    We find the first binary black hole event horizon with a toroidal topology. It has been predicted that generically the event horizons of merging black holes should briefly have a toroidal topology. However, such a phase has never been seen in numerical simulations. Instead, in all previous simulations, the topology of the event horizon transitions directly from two spheres during the inspiral to a single sphere as the black holes merge. We find a coordinate transformation to a foliation of spacelike hypersurfaces that "cut a hole" through the event horizon surface, resulting in a toroidal event horizon, thus reconciling the numerical work with theoretical expectations. The demonstration requires extremely high numerical precision, which is made possible by a new event horizon code described in a companion paper. A torus could potentially provide a mechanism for violating topological censorship. However, these toroidal event horizons satisfy topological censorship by construction, because we can always trivially apply the inverse coordinate transformation to remove the topological feature.

  19. Toroidal Horizons in Binary Black Hole Mergers

    CERN Document Server

    Bohn, Andy; Teukolsky, Saul A

    2016-01-01

    We find the first binary black hole event horizon with a toroidal topology. It had been predicted that generically the event horizons of merging black holes should briefly have a toroidal topology, but such a phase has never been seen prior to this work. In all previous binary black hole simulations, in the coordinate slicing used to evolve the black holes, the topology of the event horizon transitions directly from two spheres during the inspiral to a single sphere as the black holes merge. We present a coordinate transformation to a foliation of spacelike hypersurfaces that "cut a hole" through the event horizon surface, resulting in a toroidal event horizon. A torus could potentially provide a mechanism for violating topological censorship. However, these toroidal event horizons satisfy topological censorship by construction, because we can always trivially apply the inverse coordinate transformation to remove the topological feature.

  20. Installation Art

    DEFF Research Database (Denmark)

    Petersen, Anne Ring

    Despite its large and growing popularity – to say nothing of its near-ubiquity in the world’s art scenes and international exhibitions of contemporary art –installation art remains a form whose artistic vocabulary and conceptual basis have rarely been subjected to thorough critical examination....... In Installation Art: Between Image and Stage, Anne Ring Petersen aims to change that. She begins by exploring how installation art developed into an interdisciplinary genre in the 1960s, and how its intertwining of the visual and the performative has acted as a catalyst for the generation of new artistic...... phenomena. It investigates how it became one of today’s most widely used art forms, increasingly expanding into consumer, popular and urban cultures, where installation’s often spectacular appearance ensures that it meets contemporary demands for sense-provoking and immersive cultural experiences. The main...

  1. Celebrating the Barrel Toroid commissioning

    CERN Multimedia

    Peter Jenni

    ATLAS invited Funding Agency representatives and Laboratory Heads directly related to the funding and construction of the Barrel Toroid for a small ceremony on 13th December 2006 at Point 1, in order to mark the successful first full excitation of the BT (see last eNews). On that date, which was during the December CERN Council week, several of the Funding Agency Heads or their representatives could be present, representing CEA France, INFN Italy, BMBF Germany, Spain, Sweden, Switzerland, Russia, JINR Dubna and CERN. Speeches were delivered by the ATLAS spokesperson Peter Jenni thanking the Funding Partners in the name of the Collaboration, by Magnet Project Leader Herman ten Kate tracing the BT construction history, and by the CERN Director-General Robert Aymar congratulating all those who have contributed to the successful project. Herman ten Kate addressing the delegates. The text of the introductory address by Peter Jenni is reproduced here. "It is a great pleasure for me to welcome you all here...

  2. Toroidal eigenmodes in all-dielectric metamolecules

    Science.gov (United States)

    Tasolamprou, Anna C.; Tsilipakos, Odysseas; Kafesaki, Maria; Soukoulis, Costas M.; Economou, Eleftherios N.

    2016-11-01

    We present a thorough investigation of the electromagnetic resonant modes supported by systems of polaritonic rods placed at the vertices of canonical polygons. The study is conducted with rigorous finite-element eigenvalue simulations. To provide physical insight, the simulations are complemented with coupled mode theory (the analog of LCAO in molecular and solid state physics) and a lumped wire model capturing the coupling-caused reorganizations of the currents in each rod. The systems of rods, which form all-dielectric cyclic metamolecules, are found to support the unconventional toroidal dipole mode, consisting of the magnetic dipole mode in each rod. Besides the toroidal modes, the spectrally adjacent collective modes are identified. The evolution of all resonant frequencies with rod separation is examined. They are found to oscillate about the single-rod magnetic dipole resonance, a feature attributed to the leaky nature of the constituent modes. Importantly, we observe that ensembles of an odd number of rods produce larger frequency separation between the toroidal mode and its neighbor than the ones with an even number of rods. This increased spectral isolation, along with the low quality factor exhibited by the toroidal mode, favors the coupling of the commonly silent toroidal dipole to the outside world, rendering the proposed structure a prime candidate for controlling the observation of toroidal excitations and their interaction with the usually present electric dipole.

  3. Low-n shear Alfven spectra in axisymmetric toroidal plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, C.Z.; Chance, M.S.

    1985-11-01

    In toroidal plasmas, the toroidal magnetic field is nonuniform over a magnetic surface and causes coupling of different poloidal harmonics. It is shown both analytically and numerically that the toroidicity not only breaks up the shear Alfven continuous spectrum, but also creates new, discrete, toroidicity-induced shear Alfven eigenmodes with frequencies inside the continuum gaps. Potential applications of the low-n toroidicity-induced shear Alfven eigenmodes on plasma heating and instabilities are addressed. 17 refs., 4 figs.

  4. Conceptual Design of a New Large Superconducting Toroid for IAXO, the New International AXion Observatory

    CERN Document Server

    Shilon, I; Silva, H; Kate, H H J ten

    2013-01-01

    The International AXion Observatory (IAXO) will incorporate a new generation detector for axions, a hypothetical particle, which was postulated to solve one of the puzzles arising in the standard model of particle physics, namely the strong CP problem. The new IAXO experiment is aiming at achieving a sensitivity to the coupling between axions and photons of one order of magnitude beyond the limits of the current state-of-the-art detector, represented by the CERN Axion Solar Telescope (CAST). The IAXO detector relies on a high-magnetic field distributed over a very large volume to convert solar axions into x-ray photons. Utilizing the designs of the ATLAS barrel and end-cap toroids, a large superconducting toroidal magnet is currently being designed at CERN to provide the required magnetic field. The new toroid will be built up from eight, one meter wide and 20 m long, racetrack coils. The toroid is sized about 4 m in diameter and 22 m in length. It is designed to realize a peak magnetic field of 5.4 T with a ...

  5. Optical force on toroidal nanostructures: toroidal dipole versus renormalized electric dipole

    CERN Document Server

    Zhang, Xu-Lin; Lin, Zhifang; Sun, Hong-Bo; Chan, C T

    2015-01-01

    We study the optical forces acting on toroidal nanostructures. A great enhancement of optical force is unambiguously identified as originating from the toroidal dipole resonance based on the source-representation, where the distribution of the induced charges and currents is characterized by the three families of electric, magnetic, and toroidal multipoles. On the other hand, the resonant optical force can also be completely attributed to an electric dipole resonance in the alternative field-representation, where the electromagnetic fields in the source-free region are expressed by two sets of electric and magnetic multipole fields based on symmetry. The confusion is resolved by conceptually introducing the irreducible electric dipole, toroidal dipole, and renormalized electric dipole. We demonstrate that the optical force is a powerful tool to identify toroidal response even when its scattering intensity is dwarfed by the conventional electric and magnetic multipoles.

  6. Hall MHD Equilibrium of Accelerated Compact Toroids

    Science.gov (United States)

    Howard, S. J.; Hwang, D. Q.; Horton, R. D.; Evans, R. W.; Brockington, S. J.

    2007-11-01

    We examine the structure and dynamics of the compact toroid's magnetic field. The compact toroid is dramatically accelerated by a large rail-gun Lorentz force density equal to j xB. We use magnetic data from the Compact Toroid Injection Experiment to answer the question of exactly where in the system j xB has nonzero values, and to what extent we can apply the standard model of force-free equilibrium. In particular we present a method of analysis of the magnetic field probe signals that allows direct comparison to the predictions of the Woltjer-Taylor force-free model and Turner's generalization of magnetic relaxation in the presence of a non-zero Hall term and fluid vorticity.

  7. Ferroic nature of magnetic toroidal order.

    Science.gov (United States)

    Zimmermann, Anne S; Meier, Dennis; Fiebig, Manfred

    2014-09-05

    Electric dipoles and ferroelectricity violate spatial inversion symmetry, and magnetic dipoles and ferromagnetism break time-inversion symmetry. Breaking both symmetries favours magnetoelectric charge-spin coupling effects of enormous interest, such as multiferroics, skyrmions, polar superconductors, topological insulators or dynamic phenomena such as electromagnons. Extending the rationale, a novel type of ferroic order violating space- and time-inversion symmetry with a single order parameter should exist. This existence is fundamental and the inherent magnetoelectric coupling is technologically interesting. A uniform alignment of magnetic vortices, called ferrotoroidicity, was proposed to represent this state. Here we demonstrate that the magnetic vortex pattern identified in LiCoPO4 exhibits the indispensable hallmark of such a ferroic state, namely hysteretic poling of ferrotoroidic domains in the conjugate toroidal field, along with a distinction of toroidal from non-toroidal poling effects. This consolidates ferrotoroidicity as fourth form of ferroic order.

  8. Packing of charged chains on toroidal geometries

    Science.gov (United States)

    Yao, Zhenwei; de la Cruz, Monica Olvera

    2013-01-01

    We study a strongly adsorbed flexible polyelectrolyte chain on tori. In this generalized Thomson problem, the patterns of the adsorbed chain are analyzed in the space of the toroidal coordinates and in terms of the orientation of each chain segment. Various patterns are found, including double spirals, disclination-like structures, Janus tori, and uniform wrappings, arising from the long-range electrostatic interaction and the toroidal geometry. Their broken mirror symmetry is quantitatively characterized by introducing an order parameter, an integral of the torsion. The uniform packing, which breaks the mirror symmetry the least, has the lowest value of the order parameter. In addition, it is found that the electrostatic energy of confined chains on tori conforms to a power law regardless of the screening effect in some typical cases studied. Furthermore, we study random walks on tori that generate chain configurations in the large screening limit or at large thermal fluctuation; some features associated with the toroidal geometry are discussed.

  9. Toroidal Precession as a Geometric Phase

    Energy Technology Data Exchange (ETDEWEB)

    J.W. Burby and H. Qin

    2012-09-26

    Toroidal precession is commonly understood as the orbit-averaged toroidal drift of guiding centers in axisymmetric and quasisymmetric configurations. We give a new, more natural description of precession as a geometric phase effect. In particular, we show that the precession angle arises as the holonomy of a guiding center's poloidal trajectory relative to a principal connection. The fact that this description is physically appropriate is borne out with new, manifestly coordinate-independent expressions for the precession angle that apply to all types of orbits in tokamaks and quasisymmetric stellarators alike. We then describe how these expressions may be fruitfully employed in numerical calculations of precession.

  10. Some properties of toroidal isodynamic magnetostatic equilibria

    Energy Technology Data Exchange (ETDEWEB)

    Aly, J.-J. [AIM, Unite Mixte de Recherche CEA, CNRS, Universite Paris VII, UMR no 7158, Centre d' Etudes de Saclay, F-91191 Gif sur Yvette Cedex (France)

    2011-09-15

    We establish some general properties of a 3D isodynamic magnetostatic equilibrium admitting a family of nested toroidal flux surfaces. In particular, we use the virial theorem to prove a simple relation between the total pressure (magnetic + thermal) and the magnetic pressure on each flux surface, and we derive some useful consequences of the latter. We also show the constancy on each rational surface of two integrals along magnetic lines. As a simple application of our results, we show the nonexistence of an equilibrium with vanishing toroidal current, and of an equilibrium with closed lines.

  11. Quench modeling of the ATLAS superconducting toroids

    CERN Document Server

    Gavrilin, A V; ten Kate, H H J

    2001-01-01

    Details of the normal zone propagation and the temperature distribution in the coils of ATLAS toroids under quench are presented. A tailor-made mathematical model and corresponding computer code enable obtainment of computational results for the propagation process over the coils in transverse (turn-to-turn) and longitudinal directions. The slow electromagnetic diffusion into the pure aluminum stabilizer of the toroid's conductor, as well as the essentially transient heat transfer through inter-turn insulation, is appropriately included in the model. The effect of nonuniform distribution of the magnetic field and the thermal links to the coil casing on the temperature gradients within the coils is analyzed in full. (5 refs).

  12. Toroidal and poloidal soft x-ray imaging system on the DIII-D tokamak

    Science.gov (United States)

    Snider, R. T.; Evanko, R.; Haskovec, J.

    1988-08-01

    A toroidal soft x-ray imaging system is being added to the currently installed poloidal soft x-ray system on the DIII-D tokamak. The poloidal array is used to determine the poloidal mode structure and location of internal helical MHD perturbations in the plasma. The new array will add toroidal mode identification capability. The four detector arrays are toroidally spaced in a manner that allows identification of toroidal mode numbers up to 24. Beryllium vacuum windows separate the detectors from the tokamak vacuum and also serve as low-energy filters. The separate detector vacuum chambers can be filled with a gas that changes the low-energy cutoff of the system. By proper selection of the gas and pressure the low-energy cutoff can be chosen over the entire range of the detector sensitivity (500-1200 eV). This capability can be used to produce crude x-ray spectra for the entire imaging system or for gain control.

  13. Toroidal and poloidal soft X-ray imaging system on the D3-D tokamak

    Science.gov (United States)

    Snider, R.; Evanko, R.; Haskovec, J.

    1988-02-01

    A toroidal soft X-ray imaging system is being added to the currently installed poloidal soft X-ray system on the D3-D tokamak. The poloidal array is used to determine the poloidal mode structure and location of internal helical MHD perturbations in the plasma. The new array will add toroidal mode identification capability. The four detector arrays are toroidally spaced in a manner which allows identification of toroidal mode numbers of up to 24. Beryllium vacuum windows separate the detectors from the tokamak vacuum and also serve as low energy filters. The separate detector vacuum chambers can be filled with a gas which changes the low energy cutoff of the system. By proper selection of the gas and pressure the low energy cutoff can be chosen over the entire range of the detector sensitivity (500 eV to 1200 eV). This capability can be used to produce crude X-ray spectra for the entire imaging system or for gain control.

  14. Tearing Mode Stability with Sheared Toroidal Flows

    Science.gov (United States)

    White, Ryan; Coppi, Bruno

    2016-10-01

    Toroidal plasma flow induced by neutral beam heating has been found to increase the stability of tearing modes in tokamak plasmas. The need to extrapolate current (experimentally-based) knowledge of tearing mode onset to future machines, requiresa better understanding of the essential physics. We consider the physics of flow near the rational surfaces. For realistic flow profiles, the velocity shear near the rational surface can be treated as a perturbation, and is found to amplify the dominant stabilizing effect of magnetic curvature. This effect can be seen using a cylindrical model if large-aspect-ratio corrections to the magnetic curvature are incorporated. On the other hand, the physical effects of toroidal rotation are completely absent in a cylinder, and require a fully-toroidal calculation to study. The toroidal rotation near the rational surface is found to couple to a geometrical parameter which vanishes for up-down symmetric profiles. Physically, the dominant effects of rotation arise from a Coriolis force, leading to flow directional dependence. This work is supported by the US DOE.

  15. Toroidal surfaces compared with spherocylindrical surfaces

    Science.gov (United States)

    Malacara-Doblado, Daniel; Malacara-Hernandez, Daniel; Garcia-Marquez, Jorge L.

    1995-08-01

    Toroidal and sphero-cylindrical optical surfaces are two different kinds of surfaces (Menchaca and Malacara, 1986), but they are almost identical in the vicinity of the optical axis. The separation between these two surfaces increases when the distance to the optical axis increases. In this work the separation between these two surfaces outside of the central region is analytically studied.

  16. Reduced Magnetohydrodynamic Equations in Toroidal Geometry

    Institute of Scientific and Technical Information of China (English)

    REN Shen-Ming; YU Guo-Yang

    2001-01-01

    By applying a new assumption of density, I.e. R2 p = const, the continuity equation is satisfied to the order ofe2`+with e being the inverse aspect ratio. In the case of large aspect ratio, a set of reduced magnetohydrodynamicequations in toroidal geometry are obtained. The new assumption about the density is supported by experimentalobservation to some extent.

  17. ATLAS Barrel Toroid magnet reached nominal field

    CERN Multimedia

    2006-01-01

     On 9 November the barrel toroid magnet reached its nominal field of 4 teslas, with an electrical current of 21 000 amperes (21 kA) passing through the eight superconducting coils as shown on this graph

  18. ATLAS: Full power for the toroid magnet

    CERN Multimedia

    2006-01-01

    The 9th of November was a memorable day for ATLAS. Just before midnight, the gigantic Barrel toroid magnet reached its nominal field of 4 teslas in the coil windings, with an electrical current of 21000 amperes (21 kA) passing through the eight superconducting coils (as seen on the graph). This achievement was obtained after several weeks of commissioning. The ATLAS Barrel Toroid was first cooled down for about six weeks in July-August to -269°C (4.8 K) and then powered up step-by-step in successive test sessions to 21 kA. This is 0.5 kA above the current required to produce the nominal magnetic field. Afterwards, the current was safely switched off and the stored magnetic energy of 1.1 gigajoules was dissipated in the cold mass, raising its temperature to a safe -218°C (55 K). 'We can now say that the ATLAS Barrel Toroid is ready for physics,' said Herman ten Kate, project leader for the ATLAS magnet system. The ATLAS barrel toroid magnet is the result of a close collaboration between the magnet la...

  19. Celebration for the ATLAS Barrel Toroid magnet

    CERN Multimedia

    2007-01-01

    Representatives from Funding Agencies and Barrel Toroid Magnet Laboratories during the ceremony. From left to right: Jean Zinn-Justin (Head of DAPNIA/CEA/Saclay), CERN Director-General Robert Aymar, and Roberto Petronzio (President INFN).Allan Clark (DPNC University Geneva) and Enrique Fernandez (IFAE Barcelona) were among the guests visiting the ATLAS cavern. The barrel toroid is visible in the background. A celebration took place at Point 1 on 13 December to toast the recent powering-up of the ATLAS barrel toroid magnet to full field (Bulletin No. 47-48/06). About 70 guests were invited to attend, mainly composed of representatives from funding partners and key members of the laboratory management teams of the barrel toroid magnet, representing CEA France, INFN Italy, BMBF Germany, Spain, Sweden, Switzerland, Russia, JINR Dubna and CERN. An introductory speech by ATLAS spokesperson Peter Jenni the scene for evening. This was followed by the ATLAS magnet system project leader Herman Ten Kate's account of the...

  20. Toroidal Automorphic Forms for Function Fields

    NARCIS (Netherlands)

    Lorscheid, O.

    2008-01-01

    The definition of a toroidal automorphic form is due to Don Zagier, who showed in a paper in 1979 that the vanishing of certain integrals of Eisenstein series over tori in GL(2) is related to the vanishing of the Riemann zeta function at the weight of the Eisenstein series; and thus a relation betwe

  1. Trapped ion mode in toroidally rotating plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Artun, M.; Tang, W.M.; Rewoldt, G.

    1995-04-01

    The influence of radially sheared toroidal flows on the Trapped Ion Mode (TIM) is investigated using a two-dimensional eigenmode code. These radially extended toroidal microinstabilities could significantly influence the interpretation of confinement scaling trends and associated fluctuation properties observed in recent tokamak experiments. In the present analysis, the electrostatic drift kinetic equation is obtained from the general nonlinear gyrokinetic equation in rotating plasmas. In the long perpendicular wavelength limit k{sub {tau}}{rho}{sub bi} {much_lt} 1, where {rho}{sub bi} is the average trapped-ion banana width, the resulting eigenmode equation becomes a coupled system of second order differential equations nmo for the poloidal harmonics. These equations are solved using finite element methods. Numerical results from the analysis of low and medium toroidal mode number instabilities are presented using representative TFTR L-mode input parameters. To illustrate the effects of mode coupling, a case is presented where the poloidal mode coupling is suppressed. The influence of toroidal rotation on a TFTR L-mode shot is also analyzed by including a beam species with considerable larger temperature. A discussion of the numerical results is presented.

  2. Polar Cap Patch Dynamics

    Science.gov (United States)

    2013-04-25

    cap arcs Citation: Hosokawa, K., J. I. Moen, K. Shiokawa, and Y. Otsuka ( 2011 ), Motion of polar cap arcs , J. Geophys. Res. , 116 , A01305, doi...K., J. I. Moen, K. Shiokawa, and Y. Otsuka , (2011), Decay of polar cap patch, J. Geophys. Res., 116, A05308, doi:10.1029/2010JA016287, Abstract. We

  3. Dynamical model for the toroidal sporadic meteors

    Energy Technology Data Exchange (ETDEWEB)

    Pokorný, Petr; Vokrouhlický, David [Institute of Astronomy, Charles University, V Holešovičkách 2, CZ-18000 Prague 8 (Czech Republic); Nesvorný, David [Department of Space Studies, Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States); Campbell-Brown, Margaret; Brown, Peter, E-mail: petr.pokorny@volny.cz, E-mail: vokrouhl@cesnet.cz, E-mail: davidn@boulder.swri.edu, E-mail: margaret.campbell@uwo.ca, E-mail: pbrown@uwo.ca [Department of Physics and Astronomy, University of Western Ontario, London, ON N6A 3K7 (Canada)

    2014-07-01

    More than a decade of radar operations by the Canadian Meteor Orbit Radar have allowed both young and moderately old streams to be distinguished from the dispersed sporadic background component. The latter has been categorized according to broad radiant regions visible to Earth-based observers into three broad classes: the helion and anti-helion source, the north and south apex sources, and the north and south toroidal sources (and a related arc structure). The first two are populated mainly by dust released from Jupiter-family comets and new comets. Proper modeling of the toroidal sources has not to date been accomplished. Here, we develop a steady-state model for the toroidal source of the sporadic meteoroid complex, compare our model with the available radar measurements, and investigate a contribution of dust particles from our model to the whole population of sporadic meteoroids. We find that the long-term stable part of the toroidal particles is mainly fed by dust released by Halley type (long period) comets (HTCs). Our synthetic model reproduces most of the observed features of the toroidal particles, including the most troublesome low-eccentricity component, which is due to a combination of two effects: particles' ability to decouple from Jupiter and circularize by the Poynting-Robertson effect, and large collision probability for orbits similar to that of the Earth. Our calibrated model also allows us to estimate the total mass of the HTC-released dust in space and check the flux necessary to maintain the cloud in a steady state.

  4. New Superconducting Toroidal Magnet System for IAXO, the International AXion Observatory

    CERN Document Server

    Shilon, I; Silva, H; Wagner, U; Kate, H H J ten

    2013-01-01

    Axions are hypothetical particles that were postulated to solve one of the puzzles arising in the standard model of particle physics, namely the strong CP (Charge conjugation and Parity) problem. The new International AXion Observatory (IAXO) will incorporate the most promising solar axions detector to date, which is designed to enhance the sensitivity to the axion-photon coupling by one order of magnitude beyond the limits of the current state-of-the-art detector, the CERN Axion Solar Telescope (CAST). The IAXO detector relies on a high-magnetic field distributed over a very large volume to convert solar axions into X-ray photons. Inspired by the successful realization of the ATLAS barrel and end-cap toroids, a very large superconducting toroid is currently designed at CERN to provide the required magnetic field. This toroid will comprise eight, one meter wide and twenty one meter long, racetrack coils. The system is sized 5.2 m in diameter and 25 m in length. Its peak magnetic field is 5.4 T with a stored e...

  5. Toroidal dipole excitations in metamolecules formed by interacting plasmonic nanorods

    CERN Document Server

    Watson, Derek W; Ruostekoski, Janne; Fedotov, Vassili A; Zheludev, Nikolay I

    2015-01-01

    We show how the elusive toroidal dipole moment appears as a radiative excitation eigenmode in a metamolecule resonator that is formed by pairs of plasmonic nanorods. We analyze one such nanorod configuration - a toroidal metamolecule. We find that the radiative interactions in the toroidal metamolecule can be qualitatively represented by a theoretical model based on an electric point dipole arrangement. Both a finite-size rod model and the point dipole approximation demonstrate how the toroidal dipole moment is subradiant and difficult to excite by incident light. By means of breaking the geometric symmetry of the metamolecule, the toroidal mode can be excited by linearly polarized light and we provide simple optimization protocols for maximizing the toroidal dipole mode excitation. This opens up possibilities for simplified control and driving of metamaterial arrays consisting of toroidal dipole unit-cell resonators.

  6. Solar concentrator with a toroidal relay module.

    Science.gov (United States)

    Lin, Jhe-Syuan; Liang, Chao-Wen

    2015-10-01

    III-V multijunction solar cells require solar concentrators with a high concentration ratio to reduce per watt cost and to increase solar energy transforming efficiency. This paper discusses a novel solar concentrator design that features a high concentration ratio, high transfer efficiency, thin profile design, and a high solar acceptance angle. The optical design of the concentrator utilizes a toroidal relay module, which includes both the off-axis relay lens and field lens design in a single concentric toroidal lens shape. The optical design concept of the concentrator is discussed and the simulation results are shown. The given exemplary design has an aspect ratio of 0.24, a high averaged optical concentration ratio 1230×, a maximum efficiency of 76.8%, and the solar acceptance angle of ±0.9°.

  7. Reynolds stress of localized toroidal modes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Y.Z. [International Center for Theoretical Studies, Trieste (Italy); Mahajan, S.M. [Univ. of Texas, Austin, TX (United States). Institute for Fusion Studies

    1995-02-01

    An investigation of the 2D toroidal eigenmode problem reveals the possibility of a new consistent 2D structure, the dissipative BM-II mode. In contrast to the conventional ballooning mode, the new mode is poloidally localized at {pi}/2 (or -{pi}/2), and possesses significant radial asymmetry. The radial asymmetry, in turn, allows the dissipative BM-II to generate considerably larger Reynolds stress as compared to the standard slab drift type modes. It is also shown that a wide class of localized dissipative toroidal modes are likely to be of the dissipative BM-II nature, suggesting that at the tokamak edge, the fluctuation generated Reynolds stress (a possible source of poloidal flow) can be significant.

  8. Physics of collapses in toroidal helical plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Kimitaka [National Inst. for Fusion Science, Toki, Gifu (Japan); Itoh, Sanae; Fukuyama, Atsushi; Yagi, Masatoshi

    1998-12-31

    Theoretical model for the collapse events in toroidal helical plasmas with magnetic hill is presented. There exists a turbulent-turbulent transition at a critical pressure gradient, leading to a sudden increase of the anomalous transport. When the magnetic shear is low, the nonlinear excitation of the global mode is possible. This model explains an abrupt growth of the perturbations, i.e., the trigger phenomena. Achievable limit of the plasma beta value is discussed. (author)

  9. Aspects of Tokamak toroidal magnet protection

    Energy Technology Data Exchange (ETDEWEB)

    Green, R.W.; Kazimi, M.S.

    1979-07-01

    Simple but conservative geometric models are used to estimate the potential for damage to a Tokamak reactor inner wall and blanket due to a toroidal magnet field collapse. The only potential hazard found to exist is due to the MHD pressure rise in a lithium blanket. A survey is made of proposed protection methods for superconducting toroidal magnets. It is found that the two general classifications of protection methods are thermal and electrical. Computer programs were developed which allow the toroidal magnet set to be modeled as a set of circular filaments. A simple thermal model of the conductor was used which allows heat transfer to the magnet structure and which includes the effect of temperature dependent properties. To be effective in large magnets an electrical protection system should remove at least 50% of the stored energy in the protection circuit assuming that all of the superconductor in the circuit quenches when the circuit is activated. A protection system design procedure based on this criterion was developed.

  10. Numerical Study on Pressure Drop Factor in the Vent-Cap of CDQ Shaft

    Institute of Scientific and Technical Information of China (English)

    Bo Song; Yanhui Feng; Xinxin Zhang

    2008-01-01

    In CDQ (Coke Dry Quenching) shaft, the vent-cap with complex structure is installed in the cone-shaped funnel under the cooling chamber. It acts to introduce cooling gas and support the descending coke in the chamber. The designing and installation of vent-cap aim to get relatively uniform gas distribution, to reduce the temperature fluctuation of cokes at outlet and realize stable operation of CDQ apparatus. In this paper, the turbulent flow of gas in vent-cap of 1:7 scale CDQ experimental shaft is numerically simulated by using CFD (Computational Fluid Dynamics) software, CFX. The velocity field, the outlet flux distribution and the pressure drop factor of each outlet under three kinds of vent-cap (called high vent-cap, low vent-cap and elliptic vent-cap) are analysed and compared. The results turn out that the pressure drop factor of elliptic vent-cap is larger than the other two vent-caps, and that the pressure drop factors of high vent-cap and low vent-cap almost have the same value.While for a specified vent-cap, the pressure drop factor with pressing brick is larger than that without pressing brick. The work in this paper is valuable for the designing of vent-cap for large-acale CDQ shaft.

  11. An overview on research developments of toroidal continuously variable transmissions

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    As environmental protection agencies enact new regulations for automotive fuel economy and emission, the toroidal continuously variable transmissions (CVTs) keep on contribute to the advent of system technologies for better fuel consumption of automobiles with internal combustion engines (ICE). Toroidal CVTs use infinitely adjustable drive ratios instead of stepped gears to achieve optimal performance. Toroidal CVTs are one of the earliest patents to the automotive world but their torque capacities and reliability have limitations in the past. New developments and implementations in the control strategies, and several key technologies have led to development of more robust toroidal CVTs, which enables more extensive automotive application of toroidal CTVs. This paper concerns with the current development, upcoming and progress set in the context of the past development and the traditional problems associated with toroidal CVTs.

  12. Toroid cavity/coil NMR multi-detector

    Science.gov (United States)

    Gerald, II, Rex E.; Meadows, Alexander D.; Gregar, Joseph S.; Rathke, Jerome W.

    2007-09-18

    An analytical device for rapid, non-invasive nuclear magnetic resonance (NMR) spectroscopy of multiple samples using a single spectrometer is provided. A modified toroid cavity/coil detector (TCD), and methods for conducting the simultaneous acquisition of NMR data for multiple samples including a protocol for testing NMR multi-detectors are provided. One embodiment includes a plurality of LC resonant circuits including spatially separated toroid coil inductors, each toroid coil inductor enveloping its corresponding sample volume, and tuned to resonate at a predefined frequency using a variable capacitor. The toroid coil is formed into a loop, where both ends of the toroid coil are brought into coincidence. Another embodiment includes multiple micro Helmholtz coils arranged on a circular perimeter concentric with a central conductor of the toroid cavity.

  13. 5 case studies : boiler system increases availability of hot water in CAP REIT apartment buildings while saving energy : electric-to-gas retrofit drives down energy costs and improves building performance : Novitherm heat reflector panels saves 28 per cent in heating costs for apartment building : Novitherm heat reflector panel installation with system adjustment saves 33.2 per cent in energy costs : natural gas conversion saves over $315,000 a year for condominium

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    These 5 case studies presented the details of new systems and retrofits conducted by Enbridge Gas Distribution and its partners to improve the energy efficiency of various public and residential buildings. System retrofits included the installation of boiler system installed to address tenant demands on the domestic hot water systems of properties purchased purchased by the CAP REIT organization. The comprehensive program used to address the problems included replacement of the systems with high efficiency heating boilers designed to integrate space, hot water, ramp, and pool heat. A centralized controller included setback control, trend-following processors, and the isolation of heating equipment. The second case study described an electric-to-gas conversion of a make-up air unit and boiler system at an all-electric apartment building. The system was designed to address excessive air handling and water heating costs. The gas conversion included new heating and hot water boilers, as well as a number of efficiency upgrades. The third and fourth case study described the installation of Novitherm heat reflector panels at apartment buildings in Toronto. The fifth case study described a natural gas conversion project conducted at a luxury condominium. Energy savings for all 5 projects were presented. 9 figs.

  14. Landau damping of geodesic acoustic mode in toroidally rotating tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Haijun, E-mail: hjren@ustc.edu.cn [CAS Key Laboratory of Geospace Environment, The Collaborative Innovation Center for Advanced Fusion Energy and Plasma Science, and Department of Modern Physics, University of Science and Technology of China, Hefei 230026 (China); Cao, Jintao [Bejing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

    2015-06-15

    Geodesic acoustic mode (GAM) is analyzed by using modified gyro-kinetic (MGK) equation applicable to low-frequency microinstabilities in a rotating axisymmetric plasma. Dispersion relation of GAM in the presence of arbitrary toroidal Mach number is analytically derived. The effects of toroidal rotation on the GAM frequency and damping rate do not depend on the orientation of equilibrium flow. It is shown that the toroidal Mach number M increases the GAM frequency and dramatically decreases the Landau damping rate.

  15. Microtubule's conformational cap

    DEFF Research Database (Denmark)

    Chretien, D.; Janosi, I.; Taveau, J.C.

    1999-01-01

    The molecular mechanisms that allow elongation of the unstable microtubule lattice remain unclear. It is usually thought that the GDP-liganded tubulin lattice is capped by a small layer of GTP- or GDP-P(i)-liganded molecules, the so called "GTP-cap". Here, we point-out that the elastic properties...

  16. Development of Compact Toroid Injector for C-2 FRCs

    Science.gov (United States)

    Matsumoto, Tadafumi; Sekiguchi, Junichi; Asai, Tomohiko; Gota, Hiroshi; Garate, Eusebio; Allfrey, Ian; Valentine, Travis; Smith, Brett; Morehouse, Mark; TAE Team

    2014-10-01

    Collaborative research project with Tri Alpha Energy has been started and we have developed a new compact toroid (CT) injector for the C-2 device, mainly for fueling field-reversed configurations (FRCs). The CT is formed by a magnetized coaxial plasma-gun (MCPG), which consists of coaxial cylinder electrodes; a spheromak-like plasma is generated by discharge and pushed out from the gun by Lorentz force. The inner diameter of outer electrode is 83.1 mm and the outer diameter of inner electrode is 54.0 mm. The surface of the inner electrode is coated with tungsten in order to reduce impurities coming out from the electrode. The bias coil is mounted inside of the inner electrode. We have recently conducted test experiments and achieved a supersonic CT translation speed of up to ~100 km/s. Other typical plasma parameters are as follows: electron density ~ 5 × 1021 m-3, electron temperature ~ 40 eV, and the number of particles ~0.5-1.0 × 1019. The CT injector is now planned to be installed on C-2 and the first CT injection experiment will be conducted in the near future. The detailed MCPG design as well as the test experimental results will be presented.

  17. Multiple-applications of Accelerated Compact Toroid Injection for MFE

    Science.gov (United States)

    Hwang, David; Horton, Robert; Evans, Russell; Liu, Fei; Zhu, Ben; Hong, Sean; Buchenauer, Dean

    2010-11-01

    The CTIX experiment has explored the potential applications of launching a fast moving magnetized compact toroid for Magnetic Fusion experiments. These applications include central fueling of a MFE device such as tokamaks, stellarators, etc. At present, the UC Davis CTIX accelerator has achieved densities at mid to upper 10^15 per cc, at speeds reaching over 200 km/sec. In order to meet the parameters of even larger fusion devices, the technology of the accelerator needs to incorporate the latest plasma wall interaction findings. As a result of the next step in CT development, UC Davis will be collaborating with the Fusion Technology group at Sandia National Laboratory in Livermore California. We will be designing new plasmas facing electrodes that can reduce electrode impurities and increase electrode lifetime. In addition to producing high density CTs, we will include the updated conical compression results from our previous installed drift section compressor. In addition of the MFE applications, the ability to enhance the CT density, fields as well as speed can be useful to other fusion areas such as MIF, etc.

  18. 3D Printing the ATLAS' barrel toroid

    CERN Document Server

    Goncalves, Tiago Barreiro

    2016-01-01

    The present report summarizes my work as part of the Summer Student Programme 2016 in the CERN IR-ECO-TSP department (International Relations – Education, Communication & Outreach – Teacher and Student Programmes). Particularly, I worked closely with the S’Cool LAB team on a science education project. This project included the 3D designing, 3D printing, and assembling of a model of the ATLAS’ barrel toroid. A detailed description of the project' development is presented and a short manual on how to use 3D printing software and hardware is attached.

  19. Toroidal membrane vesicles in spherical confinement

    CERN Document Server

    Bouzar, Lila; Müller, Martin Michael

    2015-01-01

    We investigate the morphology of a toroidal fluid membrane vesicle confined inside a spherical container. The equilibrium shapes are assembled in a geometrical phase diagram as a function of scaled area and reduced volume of the membrane. For small area the vesicle can adopt its free form. When increasing the area, the membrane cannot avoid contact and touches the confining sphere along a circular contact line, which extends to a zone of contact for higher area. The elastic energies of the equilibrium shapes are compared to those of their confined counterparts of spherical topology to predict under which conditions a topology change is favored energetically.

  20. Toroidal membrane vesicles in spherical confinement

    Science.gov (United States)

    Bouzar, Lila; Menas, Ferhat; Müller, Martin Michael

    2015-09-01

    We investigate the morphology of a toroidal fluid membrane vesicle confined inside a spherical container. The equilibrium shapes are assembled in a geometrical phase diagram as a function of scaled area and reduced volume of the membrane. For small area the vesicle can adopt its free form. When increasing the area, the membrane cannot avoid contact and touches the confining sphere along a circular contact line, which extends to a zone of contact for higher area. The elastic energies of the equilibrium shapes are compared to those of their confined counterparts of spherical topology to predict under which conditions a topology change is favored energetically.

  1. Permanent magnetic toroidal drive with half stator

    Directory of Open Access Journals (Sweden)

    Lizhong Xu

    2017-01-01

    Full Text Available A permanent magnetic toroidal drive with a half stator is proposed that avoids noise and mechanical vibrations. The effects of the system parameters on the output torque of the drive were investigated. A model machine was designed and produced. The output torque and speed fluctuation of the drive system were measured, and the calculated and measured output torque were compared. The tests demonstrated that the drive system could operate continuously without noise, and the system achieved a given speed ratio. The drive system had high load-carrying ability and a maximum output torque of 0.15 N m when certain parameter values were used.

  2. Polar interface phonons in ionic toroidal systems.

    Science.gov (United States)

    Nguyen, N D; Evrard, R; Stroscio, Michael A

    2016-09-01

    We use the dielectric continuum model to obtain the polar (Fuchs-Kliewer like) interface vibration modes of toroids made of ionic materials either embedded in a different material or in vacuum, with applications to nanotoroids specially in mind. We report the frequencies of these modes and describe the electric potential they produce. We establish the quantum-mechanical Hamiltonian appropriate for their interaction with electric charges. This Hamiltonian can be used to describe the effect of this interaction on different types of charged particles either inside or outside the torus.

  3. Cradle Cap (For Parents)

    Science.gov (United States)

    ... is the common term for seborrheic dermatitis , or seborrhea, which is called dandruff in older kids and ... another factor in the development of cradle cap. Seborrhea happens most often in babies and teenagers. In ...

  4. Experiments with low energy ion beam transport into toroidal magnetic fields

    CERN Document Server

    Joshi, N; Meusel, O; Ratzinger, U

    2016-01-01

    The stellarator-type storage ring for accumulation of multi- Ampere proton and ion beams with energies in the range of $100~AkeV$ to $1~AMeV$ is designed at Frankfurt university. The main idea for beam confinement with high transversal momentum acceptance was presented in EPAC2006. This ring is typically suited for experiments in plasma physics and nuclear astrophysics. The accumulator ring with a closed longitudinal magnetic field is foreseen with a strength up to $6-8~T$. The experiments with two room temperature 30 degree toroids are needed. The beam transport experiments in toroidal magnetic fields were first described in EPAC2008 within the framework of a proposed low energy ion storage ring. The test setup aims on developing a ring injection system with two beam lines representing the main beam line and the injection line. The primary beam line for the experiments was installed and successfully commissioned in 2009. A special diagnostics probe for \\textit{"in situ"} ion beam detection was installed.This...

  5. Formation of a compact toroid for enhanced efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Mozgovoy, A. G. [P.N. Lebedev Physical Institute, Moscow 119991 (Russian Federation); Romadanov, I. V.; Ryzhkov, S. V., E-mail: ryzhkov@power.bmstu.ru [Bauman Moscow State Technical University, Moscow 105005 (Russian Federation)

    2014-02-15

    We report here our results on the formation of a plasma configuration with the generic name of compact toroid (CT). A method of compact toroid formation to confine, heat and compress a plasma is investigated. Formation of a compact torus using an additional toroidal magnetic field helps to increase the plasma current to a maintainable level of the original magnetic field. We design the Compact Toroid Challenge (CTC) experiment in order to improve the magnetic flux trapping during field reversal in the formation of a compact toroid. The level of the magnetic field immersed in the plasma about 70% of the primary field is achieved. The CTC device and scheme of high level capturing of magnetic flux are presented.

  6. Shear-dependant toroidal vortex flow

    Energy Technology Data Exchange (ETDEWEB)

    Khorasani, Nariman Ashrafi; Haghighi, Habib Karimi [Payame Noor University, Tehran (Iran, Islamic Republic of)

    2013-01-15

    Pseudoplastic circular Couette flow in annulus is investigated. The flow viscosity is dependent on the shear rate, which directly affects the conservation equations that are solved in the present study by the spectral method in the present study. The pseudoplastic model adopted here is shown to be a suitable representative of nonlinear fluids. Unlike the previous studies, where only the square of shear rate term in the viscosity expression was considered to ease the numerical manipulations, in the present study takes the term containing the quadratic power into account. The curved streamlines of the circular Couette flow can cause a centrifugal instability leading to toroidal vortices, known as Taylor vortices. It is further found that the critical Taylor number becomes lower as the pseudoplastic effect increases. Comparison with existing measurements on pseudoplastic circular Couette flow results in good agreement.

  7. Helicity of the toroidal vortex with swirl

    CERN Document Server

    Bannikova, Elena Yu; Poslavsky, Sergey A

    2016-01-01

    On the basis of solutions of the Bragg-Hawthorne equations we discuss the helicity of thin toroidal vortices with the swirl - the orbital motion along the torus diretrix. It is shown that relationship of the helicity with circulations along the small and large linked circles - directrix and generatrix of the torus - depends on distribution of the azimuthal velocity in the core of the swirling vortex ring. In the case of non-homogeneous swirl this relationship differs from the well-known Moffat relationship - the doubled product of such circulations multiplied by the number of links. The results can be applied to vortices in planetary atmospheres and to vortex movements in the vicinity of active galactic nuclei.

  8. The theory of toroidally confined plasmas

    CERN Document Server

    White, Roscoe B

    2014-01-01

    This graduate level textbook develops the theory of magnetically confined plasma, with the aim of bringing the reader to the level of current research in the field of thermonuclear fusion. It begins with the basic concepts of magnetic field description, plasma equilibria and stability, and goes on to derive the equations for guiding center particle motion in an equilibrium field. Topics include linear and nonlinear ideal and resistive modes and particle transport. It is of use to workers in the field of fusion both for its wide-ranging account of tokamak physics and as a kind of handbook or formulary. This edition has been extended in a number of ways. The material on mode-particle interactions has been reformulated and much new information added, including methodology for Monte Carlo implementation of mode destabilization. These results give explicit means of carrying out mode destabilization analysis, in particular for the dangerous fishbone mode. A new chapter on cyclotron motion in toroidal geometry has ...

  9. Damping of toroidal ion temperature gradient modes

    Energy Technology Data Exchange (ETDEWEB)

    Sugama, H. [National Inst. for Fusion Science, Toki, Gifu (Japan)

    1999-04-01

    The temporal evolution of linear toroidal ion temperature gradient (ITG) modes is studied based on a kinetic integral equation including an initial condition. It is shown how to evaluate the analytic continuation of the integral kernel as a function of a complex-valued frequency, which is useful for analytical and numerical calculations of the asymptotic damping behavior of the ITG mode. In the presence of the toroidal {nabla}B-curvature drift, the temporal dependence of the density and potential perturbations consists of normal modes and a continuum mode, which correspond to contributions from poles and from an integral along a branch cut, respectively, of the Laplace-transformed potential function of the complex-valued frequency. The normal modes have exponential time dependence with frequencies and growth rates determined by the dispersion relation while the continuum mode, which has a ballooning structure, shows a power law decay {proportional_to} t{sup -2} in the asymptotic limit, where t is the time variable. Therefore, the continuum mode dominantly describes the long-time asymptotic behavior of the density and potential perturbations for the stable system where all normal modes have negative growth rates. By performing proper analytic continuation for the homogeneous version of the kinetic integral equation, dependences of the normal modes` growth rate, real frequency, and eigenfunction on {eta}{sub i} (the ratio of the ion temperature gradient to the density gradient), k{sub {theta}} (the poloidal wavenumber), s (the magnetic shear parameter), and {theta}{sub k} (the ballooning angle corresponding to the minimum radial wavenumber) are numerically obtained for both stable and unstable cases. (author)

  10. Concept design of the cassette toroidal mover

    Energy Technology Data Exchange (ETDEWEB)

    Maekinen, H., E-mail: harri.makinen@vtt.fi [VTT Technical Research Centre of Finland, P.O. Box 1300, FI-33101 Tampere (Finland); Jaervenpaeae, J. [VTT Technical Research Centre of Finland, P.O. Box 1300, FI-33101 Tampere (Finland); Valkama, P.; Vaeyrynen, J.; Amjad, F. [Tampere University of Technology, Korkeakoulunkatu 6, 33720 Tampere (Finland); Siuko, M. [VTT Technical Research Centre of Finland, P.O. Box 1300, FI-33101 Tampere (Finland); Mattila, J. [Tampere University of Technology, Korkeakoulunkatu 6, 33720 Tampere (Finland); Semeraro, L.; Esque, S. [Fusion for Energy, Torres Diagonal Litoral B3, Josep Pla 2, 08019 Barcelona (Spain)

    2011-10-15

    A full scale physical development and test facility, Divertor Test Platform 2 (DTP2), has been established in Finland for the purpose of demonstrating and developing the remote handling (RH) equipment designs for ITER using prototypes and virtual models. The major objective of the DTP2 environment is to verify and develop ITER divertor RH devices and operations. In practice this means various test trials and measurements of performance characteristics. This paper describes the design process of the Cassette Toroidal Mover (CTM). The main purpose of this design task was the development of the CTM concept. The goal of the design process was to achieve compatibility between CTM and the latest ITER divertor design. The design process was based on using a variety of tools, i.e. Catia V5, Delmia, Ansys, Mathcad and project management tools. Applicable European Standards were applied to the concept design. CTM is the cassette transporter, which carries divertor cassettes on the toroidal rails inside the ITER Vacuum Vessel (VV) during the divertor maintenance. The operation environment differs from a common industrial environment. Radiation level is 100 Gy/h. The temperature during RH operations can be 50 {sup o}C. Clearances are less than 20 mm and the loads carried weigh 9000 kg. These conditions require special solutions during the product development process. The design process consisted of defining and developing of the CTM operational sequence. This sequence includes the procedure of how the CTM - with it is onboard manipulator - prepares for and handles the divertor cassettes during RH operations. RH operations are essential part when defining CTM functions. High reliability is required in order to carry out RH tasks successfully. The recoverability of CTM is also an important design criteria. This paper describes the design process and the structure of the CTM concept.

  11. Petascale Parallelization of the Gyrokinetic Toroidal Code

    Energy Technology Data Exchange (ETDEWEB)

    Ethier, Stephane; Adams, Mark; Carter, Jonathan; Oliker, Leonid

    2010-05-01

    The Gyrokinetic Toroidal Code (GTC) is a global, three-dimensional particle-in-cell application developed to study microturbulence in tokamak fusion devices. The global capability of GTC is unique, allowing researchers to systematically analyze important dynamics such as turbulence spreading. In this work we examine a new radial domain decomposition approach to allow scalability onto the latest generation of petascale systems. Extensive performance evaluation is conducted on three high performance computing systems: the IBM BG/P, the Cray XT4, and an Intel Xeon Cluster. Overall results show that the radial decomposition approach dramatically increases scalability, while reducing the memory footprint - allowing for fusion device simulations at an unprecedented scale. After a decade where high-end computing (HEC) was dominated by the rapid pace of improvements to processor frequencies, the performance of next-generation supercomputers is increasingly differentiated by varying interconnect designs and levels of integration. Understanding the tradeoffs of these system designs is a key step towards making effective petascale computing a reality. In this work, we examine a new parallelization scheme for the Gyrokinetic Toroidal Code (GTC) [?] micro-turbulence fusion application. Extensive scalability results and analysis are presented on three HEC systems: the IBM BlueGene/P (BG/P) at Argonne National Laboratory, the Cray XT4 at Lawrence Berkeley National Laboratory, and an Intel Xeon cluster at Lawrence Livermore National Laboratory. Overall results indicate that the new radial decomposition approach successfully attains unprecedented scalability to 131,072 BG/P cores by overcoming the memory limitations of the previous approach. The new version is well suited to utilize emerging petascale resources to access new regimes of physical phenomena.

  12. On the use of a toroidal mirror to focus neutrons at the ILL neutron spin echo spectrometer IN15

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, C. [Institut Laue-Langevin, Grenoble (France); Alefeld, B. [Forschungszentrum Juelich GmbH, Juelich (Germany); Copley, J.R.D. [National Institute of Standards and Technology, Gaithersburg, MD (United States)] [and others

    1997-09-01

    The IN15 neutron spin echo spectrometer at the Institut Laue-Langevin (Grenoble) has been designed to accomodate a toroidal focusing mirror. This mirror will be used to increase the intensity at the sample position for measurements at long neutron wavelengths and to perform measurements in the low q-range (10{sup -3} {angstrom}{sup -1}). This paper summarizes the results of ray-tracing simulations for the toroidal mirror system. These calculations were performed in order to assess the effects of the neutron wavelength, gravitational fall, wavelength resolution and spherical aberrations on the quality of the focused beam. The gain in flux that can be expected from the focusing geometry is estimated. The recent installation and characterisation of the mirror is also briefly described.

  13. MARK II end cap calorimeter electronics

    Energy Technology Data Exchange (ETDEWEB)

    Jared, R.C.; Haggerty, J.S.; Herrup, D.A.; Kirsten, F.A.; Lee, K.L.; Olson, S.R.; Wood, D.R.

    1985-10-01

    An end cap calorimeter system has been added to the MARK II detector in preparation for its use at the SLAC Linear Collider. The calorimeter uses 8744 rectangular proportional counter tubes. This paper describes the design features of the data acquisition electronics that has been installed on the calorimeter. The design and use of computer-based test stands for the amplification and signal-shaping components is also covered. A portion of the complete system has been tested in a beam at SLAC. In these initial tests, using only the calibration provided by the test stands, a resolution of 18%/..sqrt..E was achieved.

  14. Gaseous toroid around Saturn. [Saturnian ring system for atomic hydrogen trapping in Titan atmospheric model

    Science.gov (United States)

    Mcdonough, T. R.

    1974-01-01

    The trapping of Titan's escaping atmosphere in the Saturnian system by a toroidal ring is discussed. The radius of the toroid is comparable to Titan's orbit, or about ten times larger than the visible rings. Theoretical atmospheric models are formulated that consider Saturn's gravitational attraction and magnetospheric properties in forming this toroid and in protecting toroid particles from direct ionization by solar wind particles.

  15. Toroidicity Dependence of Tokamak Edge Safety Factor and Shear

    Institute of Scientific and Technical Information of China (English)

    SHIBingren

    2002-01-01

    In large tokamak device and reactor designs, the relationship between the toroidal current and the edge safety factor is very important because this will determine the eventual device or reactor size according to MHD stability requirements. In many preliminary

  16. Influence of toroidal rotation on resistive tearing modes in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Wang, S.; Ma, Z. W., E-mail: zwma@zju.edu.cn [Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China)

    2015-12-15

    Influence of toroidal equilibrium plasma rotation on m/n = 2/1 resistive tearing modes is studied numerically using a 3D toroidal MHD code (CLT). It is found that the toroidal rotation with or without shear can suppress the tearing instability and the Coriolis effect in the toroidal geometry plays a dominant role on the rotation induced stabilization. For a high viscosity plasma (τ{sub R}/τ{sub V} ≫ 1, where τ{sub R} and τ{sub V} represent resistive and viscous diffusion time, respectively), the effect of the rotation shear combined with the viscosity appears to be stabilizing. For a low viscosity plasmas (τ{sub R}/τ{sub V} ≪ 1), the rotation shear shows a destabilizing effect when the rotation is large.

  17. Influence of toroidal rotation on resistive tearing modes in tokamaks

    Science.gov (United States)

    Wang, S.; Ma, Z. W.

    2015-12-01

    Influence of toroidal equilibrium plasma rotation on m/n = 2/1 resistive tearing modes is studied numerically using a 3D toroidal MHD code (CLT). It is found that the toroidal rotation with or without shear can suppress the tearing instability and the Coriolis effect in the toroidal geometry plays a dominant role on the rotation induced stabilization. For a high viscosity plasma (τR/τV ≫ 1, where τR and τV represent resistive and viscous diffusion time, respectively), the effect of the rotation shear combined with the viscosity appears to be stabilizing. For a low viscosity plasmas (τR/τV ≪ 1), the rotation shear shows a destabilizing effect when the rotation is large.

  18. North Polar Cap

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] This week we will be looking at five examples of laminar wind flow on the north polar cap. On Earth, gravity-driven south polar cap winds are termed 'catabatic' winds. Catabatic winds begin over the smooth expanse of the cap interior due to temperature differences between the atmosphere and the surface. Once begun, the winds sweep outward along the surface of the polar cap toward the sea. As the polar surface slopes down toward sealevel, the wind speeds increase. Catabatic wind speeds in the Antartic can reach several hundreds of miles per hour. In the images of the Martian north polar cap we can see these same type of winds. Notice the streamers of dust moving downslope over the darker trough sides, these streamers show the laminar flow regime coming off the cap. Within the trough we see turbulent clouds of dust, kicked up at the trough base as the winds slow down and enter a chaotic flow regime. The horizontal lines in these images are due to framelet overlap and lighting conditions over the bright polar cap. Image information: VIS instrument. Latitude 86.5, Longitude 64.5 East (295.5 West). 40 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen

  19. 3D blob dynamics in toroidal geometry

    DEFF Research Database (Denmark)

    Nielsen, Anders Henry; Reiser, Dirk

    . The DIESEL code is an extension of the ESEL code [1]. It solves a simple interchange model in full 3D tokamak geometry, where the toroidal direction is divided into a number of drift planes. On each drift plane the equations are solved in a domain corresponding to the full 2D cross section of the tokamak......In this paper we study the simple case of the dynamics of a density perturbation localized in the edge region of a medium sized tokamak in a full 3D geometry. The 2D evolution of such a perturbation has been studied in details on the low-field side, where the gradient of the magnetic field always...... point radial inward, see e.g. [1-2]. Here, the initial condition is implemented in two very different 3D numerical codes, ATTEMPT [3], and a new developed code, DIESEL (Disk version of ESEL), and the results are compared and discussed in detail. The ATTEMPT code has been employed to study the blob...

  20. Compact toroid injection into C-2U

    Science.gov (United States)

    Roche, Thomas; Gota, H.; Garate, E.; Asai, T.; Matsumoto, T.; Sekiguchi, J.; Putvinski, S.; Allfrey, I.; Beall, M.; Cordero, M.; Granstedt, E.; Kinley, J.; Morehouse, M.; Sheftman, D.; Valentine, T.; Waggoner, W.; the TAE Team

    2015-11-01

    Sustainment of an advanced neutral beam-driven FRC for a period in excess of 5 ms is the primary goal of the C-2U machine at Tri Alpha Energy. In addition, a criteria for long-term global sustainment of any magnetically confined fusion reactor is particle refueling. To this end, a magnetized coaxial plasma-gun has been developed. Compact toroids (CT) are to be injected perpendicular to the axial magnetic field of C-2U. To simulate this environment, an experimental test-stand has been constructed. A transverse magnetic field of B ~ 1 kG is established (comparable to the C-2U axial field) and CTs are fired across it. As a minimal requirement, the CT must have energy density greater than that of the magnetic field it is to penetrate, i.e., 1/2 ρv2 >=B2 / 2μ0 . This criteria is easily met and indeed the CTs traverse the test-stand field. A preliminary experiment on C-2U shows the CT also capable of penetrating into FRC plasmas and refueling is observed resulting in a 20 - 30% increase in total particle number per single-pulsed CT injection. Results from test-stand and C-2U experiments will be presented.

  1. Sawtooth Instability in the Compact Toroidal Hybrid

    Science.gov (United States)

    Herfindal, J. L.; Maurer, D. A.; Hartwell, G. J.; Ennis, D. A.; Knowlton, S. F.

    2015-11-01

    Sawtooth instabilities have been observed in the Compact Toroidal Hybrid (CTH), a current-carrying stellarator/tokamak hybrid device. The sawtooth instability is driven by ohmic heating of the core plasma until the safety factor drops below unity resulting in the growth of an m = 1 kink-tearing mode. Experiments varying the vacuum rotational transform from 0.02 to 0.13 are being conducted to study sawtooth property dependance on vacuum flux surface structure. The frequency of the sawtooth oscillations increase from 2 kHz to 2.8 kHz solely due the decrease in rise time of the oscillation, the crash time is unchanged. CTH has three two-color SXR cameras, a three-channel 1mm interferometer, and a new bolometer system capable of detecting the signatures of sawtooth instabilities. The new bolometer system consists of two cameras, each containing a pair of diode arrays viewing the plasma directly or through a beryllium filter. Electron temperature measurements are found with the two-color SXR cameras through a ratio of the SXR intensities. Impurity radiation can drastically affect the electron temperature measurement, therefore new filters consisting of aluminum and carbon were selected to avoid problematic line radiation while maximizing the signal for a 100 eV plasma. This work is supported by U.S. Department of Energy Grant No. DE-FG02-00ER54610.

  2. Ballooning mode spectrum in general toroidal systems

    Energy Technology Data Exchange (ETDEWEB)

    Dewar, R.L.; Glasser, A.H.

    1982-04-01

    A WKB formalism for constructing normal modes of short-wavelength ideal hydromagnetic, pressure-driven instabilities (ballooning modes) in general toroidal magnetic containment devices with sheared magnetic fields is developed. No incompressibility approximation is made. A dispersion relation is obtained from the eigenvalues of a fourth order system of ordinary differential equations to be solved by integrating along a line of force. Higher order calculations are performed to find the amplitude equation and the phase change at a caustic. These conform to typical WKB results. In axisymmetric systems, the ray equations are integrable, and semiclassical quantization leads to a growth rate spectrum consisting of an infinity of discrete eigenvalues, bounded above by an accumulation point. However, each eigenvalue is infinitely degenerate. In the nonaxisymmetric case, the rays are unbounded in a four dimensional phase space, and semiclassical quantization breaks down, leading to broadening of the discrete eigenvalues and accumulation point of the axisymmetric case into continuum bands. Analysis of a model problem indicates that the broadening of the discrete eigenvalues is numerically very small, the dominant effect being broadening of the accumulation point.

  3. Turbulent Equipartition Theory of Toroidal Momentum Pinch

    Energy Technology Data Exchange (ETDEWEB)

    T.S. Hahm, P.H. Diamond, O.D. Gurcan, and G. Rewaldt

    2008-01-31

    The mode-independet part of magnetic curvature driven turbulent convective (TuroCo) pinch of the angular momentum density [Hahm et al., Phys. Plasmas 14,072302 (2007)] which was originally derived from the gyrokinetic equation, can be interpreted in terms of the turbulent equipartition (TEP) theory. It is shown that the previous results can be obtained from the local conservation of "magnetically weighted angular momentum density," nmi U|| R/B2, and its homogenization due to turbulent flows. It is also demonstrated that the magnetic curvature modification of the parallel acceleration in the nonlinear gyrokinetic equation in the laboratory frame, which was shown to be responsible for the TEP part of the TurCo pinch of angular momentum density in the previous work, is closely related to the Coriolis drift coupling to the perturbed electric field. In addition, the origin of the diffusive flux in the rotating frame is highlighted. Finally, it is illustratd that there should be a difference in scalings between the momentum pinch originated from inherently toroidal effects and that coming from other mechanisms which exist in a simpler geometry.

  4. Electric disruption in a hydrogen toroidal plasma; Ruptura eletrica em um plasma toroidal em hidrogenio

    Energy Technology Data Exchange (ETDEWEB)

    Roberto, M. [UNESP, Guaratingueta, SP (Brazil). Faculdade de Engenharia. Dept. de Fisica; Silva, C.A.B. [Centro Tecnico Aeroespacial (CTA-IEAv), Sao Jose dos Campos, SP (Brazil). Inst. de Estudos Avancados; Goes, L.C.S.; Sudano, J.P. [Centro Tecnico Aeroespacial, Sao Jose dos Campos, SP (Brazil). Inst. Tecnologico de Aeronautica

    1990-12-31

    By using a zero-dimensional model the ionizing initial phase of a toroidal plasma produced in hydrogen was investigated. The model consists on describing the plasma time evolution through the density and particle temperature space averaged on the plasma volume. The involved equations are energy and particles balance equations (electrons and ions). The electron loss is due to ambipolar diffusion in the presence of magnetic field. The electron energy loss is due to ionizing, processes of Coulomb interaction and diffusion. The ohmic heating transformer gives a initial voltage necessary to the breaking 11 refs., 2 figs.

  5. An important step for the ATLAS toroid magnet

    CERN Multimedia

    2000-01-01

    The ATLAS experiment's prototype toroid coil arrives at CERN from the CEA laboratory in Saclay on 6 October. The world's largest superconducting toroid magnet is under construction for the ATLAS experiment. A nine-metre long fully functional prototype coil was delivered to CERN at the beginning of October and has since been undergoing tests in the West Area. Built mainly by companies in France and Italy under the supervision of engineers from the CEA-Saclay laboratory near Paris and Italy's INFN-LASA, the magnet is a crucial step forward in the construction of the ATLAS superconducting magnet system. Unlike any particle detector that has gone before, the ATLAS detector's magnet system consists of a large toroidal system enclosing a small central solenoid. The barrel part of the toroidal system will use eight toroid coils, each a massive 25 metres in length. These will dwarf the largest toroids in the world when ATLAS was designed, which measure about six metres. So the ATLAS collaboration decided to build a...

  6. Toroidal momentum pinch velocity due to the coriolis drift effect on small scale instabilities in a toroidal plasma.

    Science.gov (United States)

    Peeters, A G; Angioni, C; Strintzi, D

    2007-06-29

    In this Letter, the influence of the "Coriolis drift" on small scale instabilities in toroidal plasmas is shown to generate a toroidal momentum pinch velocity. Such a pinch results because the Coriolis drift generates a coupling between the density and temperature perturbations on the one hand and the perturbed parallel flow velocity on the other. A simple fluid model is used to highlight the physics mechanism and gyro-kinetic calculations are performed to accurately assess the magnitude of the pinch. The derived pinch velocity leads to a radial gradient of the toroidal velocity profile even in the absence of a torque on the plasma and is predicted to generate a peaking of the toroidal velocity profile similar to the peaking of the density profile. Finally, the pinch also affects the interpretation of current experiments.

  7. Progress in LAr EndCap Calorimetry: News from the Hadronic EndCap Group.

    CERN Multimedia

    Oram, C.J.

    With module production and testing completed for the Hadronic EndCap calorimeter, the attention of the HEC group is heavily directed towards wheel assembly in building 180. Three of the four HEC wheels are now assembled and rotated, and work is progressing on assembling the final wheel. This year has been a busy year for the installation of components in the EndCap C cryostat: the signal feedthrough installation was completed April 22nd, the pre-sampler shortly thereafter and the Electro-Magnetic EndCap August 13th. This allowed the HEC group to start transferring the HEC wheels from the T6A storage cradle into the cryostat. The operation started in mid-September and has progressed, on or ahead of schedule, since then with the major milestones being: Insertion of 67 ton front HEC wheel October 3rd Insertion of 90 ton rear HEC wheel October 22nd. The wheel alignment has proved to be excellent, with the position of the centre of the front(rear) wheel with respect to the nominal position being displaced b...

  8. Test Results of a 1.2 kg/s Centrifugal Liquid Helium Pump for the ATLAS Superconducting Toroid Magnet System

    CERN Document Server

    Pengo, R; Passardi, Giorgio; Pirotte, O; ten Kate, H H J

    2002-01-01

    The toroid superconducting magnet of ATLAS-LHC experiment at CERN will be indirectly cooled by means of forced flow of liquid helium at about 4.5 K. A centrifugal pump will be used, providing a mass flow of 1.2 kg/s and a differential pressure of 40 kPa (ca. 400 mbar) at about 4300 rpm. Two pumps are foreseen, one for redundancy, in order to feed in parallel the cooling circuits of the Barrel and the two End-Caps toroid magnets. The paper describes the tests carried out at CERN to measure the characteristic curves, i.e. the head versus the mass flow at different rotational speeds, as well as the pump total efficiency. The pump is of the "fullemission" type, i.e. with curved blades and it is equipped with an exchangeable inducer. A dedicated pump test facility has been constructed at CERN, which includes a Coriolis-type liquid helium mass flow meter. This facility is connected to the helium refrigerator used for the tests at CERN of the racetrack magnets of the Barrel and of the End-Cap toroids.

  9. Design of a new toroidal shell and support structure for RFX

    Energy Technology Data Exchange (ETDEWEB)

    Baker, W.; Dal Bello, S. E-mail: dalbello@igi.pd.cnr.it; Marcuzzi, D.; Sonato, P.; Zaccaria, P

    2002-12-01

    The physics results obtained from RFP experiments at high current (0.8-1 MA) indicate the need for a better control of the plasma MHD modes, which grow rapidly and lock to the wall during the pulse. The modifications planned for the RFX machine have been designed to guarantee both a passive and an active control of these modes. The present 65 mm thick aluminium shell will be replaced by a 3 mm thick copper shell which is assembled on the vacuum vessel, closer to the plasma edge. In addition 192 saddle coils will be installed to actively control the main mode spectrum of RFX. As a result of these modifications, a new toroidal support structure will be required, which carries out the mechanical functions of the previous shell and supports the new saddle coils. This paper deals with the design of the thin shell and toroidal structure. The solutions which guarantee the required safety level, from a mechanical and thermal point of view, and the technological details of the electrical insulation systems for the various components are highlighted.

  10. LHC installation planning

    CERN Document Server

    Weisz, S

    2005-01-01

    installation of the general services, the installation of the cryogenic line (QRL), the installation of the machine elements and the hardware commissioning. While the installation of the general services is now almost finished (see presentation by Katy Foraz and Serge Grillot), several problems and delays with the QRL made it unavoidable to revise the installation strategy and to schedule a number tasks in parallel. A new compressed installation planning has been issued, that fulfils the strategic objectives and allows starting new activities with minimal delays in sectors 7-8 and 8-1. However, the shortcuts that are introduced increase the level of risk that we will have to face and the coordination of such a large and complex variety of simultaneous activities makes the project even more challenging. The document will describe how the input from the different equipment groups is taken into account by the master schedule planning team with respect to equipment availability and production as well as logistics...

  11. Solid Rocket Booster Hydraulic Pump Port Cap Joint Load Testing

    Science.gov (United States)

    Gamwell, W. R.; Murphy, N. C.

    2004-01-01

    The solid rocket booster uses hydraulic pumps fabricated from cast C355 aluminum alloy, with 17-4 PH stainless steel pump port caps. Corrosion-resistant steel, MS51830 CA204L self-locking screw thread inserts are installed into C355 pump housings, with A286 stainless steel fasteners installed into the insert to secure the pump port cap to the housing. In the past, pump port cap fasteners were installed to a torque of 33 Nm (300 in-lb). However, the structural analyses used a significantly higher nut factor than indicated during tests conducted by Boeing Space Systems. When the torque values were reassessed using Boeing's nut factor, the fastener preload had a factor of safety of less than 1, with potential for overloading the joint. This paper describes how behavior was determined for a preloaded joint with a steel bolt threaded into steel inserts in aluminum parts. Finite element models were compared with test results. For all initial bolt preloads, bolt loads increased as external applied loads increased. For higher initial bolt preloads, less load was transferred into the bolt, due to external applied loading. Lower torque limits were established for pump port cap fasteners and additional limits were placed on insert axial deformation under operating conditions after seating the insert with an initial preload.

  12. Electrical installation calculations advanced

    CERN Document Server

    Kitcher, Christopher

    2013-01-01

    All the essential calculations required for advanced electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practiceA step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3For apprentices and electrical installatio

  13. Electrical installation calculations basic

    CERN Document Server

    Kitcher, Christopher

    2013-01-01

    All the essential calculations required for basic electrical installation workThe Electrical Installation Calculations series has proved an invaluable reference for over forty years, for both apprentices and professional electrical installation engineers alike. The book provides a step-by-step guide to the successful application of electrical installation calculations required in day-to-day electrical engineering practice. A step-by-step guide to everyday calculations used on the job An essential aid to the City & Guilds certificates at Levels 2 and 3Fo

  14. Electrical installations and regulations

    CERN Document Server

    Whitfield, J F

    1966-01-01

    Electrical Installations and Regulations focuses on the regulations that apply to electrical installations and the reasons for them. Topics covered range from electrical science to alternating and direct current supplies, as well as equipment for providing protection against excess current. Cables, wiring systems, and final subcircuits are also considered, along with earthing, discharge lighting, and testing and inspection.Comprised of 12 chapters, this book begins with an overview of electrical installation work, traits of a good electrician, and the regulations governing installations. The r

  15. Saltstone Clean Cap Formulation

    Energy Technology Data Exchange (ETDEWEB)

    Langton, C

    2005-04-22

    The current operation strategy for using Saltstone Vault 4 to receive 0.2 Ci/gallon salt solution waste involves pouring a clean grout layer over the radioactive grout prior to initiating pour into another cell. This will minimize the radiating surface area and reduce the dose rate at the vault and surrounding area. The Clean Cap will be used to shield about four feet of Saltstone poured into a Z-Area vault cell prior to moving to another cell. The minimum thickness of the Clean Cap layer will be determined by the cesium concentration and resulting dose levels and it is expected to be about one foot thick based on current calculations for 0.1 Ci Saltstone that is produced in the Saltstone process by stabilization of 0.2 Ci salt solution. This report documents experiments performed to identify a formulation for the Clean Cap. Thermal transient calculations, adiabatic temperature rise measurements, pour height, time between pour calculations and shielding calculations were beyond the scope and time limitations of this study. However, data required for shielding calculations (composition and specific gravity) are provided for shielding calculations. The approach used to design a Clean Cap formulation was to produce a slurry from the reference premix (10/45/45 weight percent cement/slag/fly ash) and domestic water that resembled as closely as possible the properties of the Saltstone slurry. In addition, options were investigated that may offer advantages such as less bleed water and less heat generation. The options with less bleed water required addition of dispersants. The options with lower heat contained more fly ash and less slag. A mix containing 10/45/45 weight percent cement/slag/fly ash with a water to premix ratio of 0.60 is recommended for the Clean Cap. Although this mix may generate more than 3 volume percent standing water (bleed water), it has rheological, mixing and flow properties that are similar to previously processed Saltstone. The recommended

  16. Analytical solutions for Tokamak equilibria with reversed toroidal current

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Caroline G. L.; Roberto, M.; Braga, F. L. [Departamento de Fisica, Instituto Tecnologico de Aeronautica, Sao Jose dos Campos, Sao Paulo 12228-900 (Brazil); Caldas, I. L. [Instituto de Fisica, Universidade de Sao Paulo, 05315-970 Sao Paulo, SP (Brazil)

    2011-08-15

    In tokamaks, an advanced plasma confinement regime has been investigated with a central hollow electric current with negative density which gives rise to non-nested magnetic surfaces. We present analytical solutions for the magnetohydrodynamic equilibria of this regime in terms of non-orthogonal toroidal polar coordinates. These solutions are obtained for large aspect ratio tokamaks and they are valid for any kind of reversed hollow current density profiles. The zero order solution of the poloidal magnetic flux function describes nested toroidal magnetic surfaces with a magnetic axis displaced due to the toroidal geometry. The first order correction introduces a poloidal field asymmetry and, consequently, magnetic islands arise around the zero order surface with null poloidal magnetic flux gradient. An analytic expression for the magnetic island width is deduced in terms of the equilibrium parameters. We give examples of the equilibrium plasma profiles and islands obtained for a class of current density profile.

  17. Ultra-high-Q toroidal microresonators for cavity quantum electrodynamics

    CERN Document Server

    Spillane, S M; Vahala, K J; Goh, K W; Wilcut, E; Kimble, H J

    2004-01-01

    We investigate the suitability of toroidal microcavities for strong-coupling cavity quantum electrodynamics (QED). Numerical modeling of the optical modes demonstrate a significant reduction of modal volume with respect to the whispering gallery modes of dielectric spheres, while retaining the high quality factors representative of spherical cavities. The extra degree of freedom of toroid microcavities can be used to achieve improved cavity QED characteristics. Numerical results for atom-cavity coupling strength, critical atom number N_0 and critical photon number n_0 for cesium are calculated and shown to exceed values currently possible using Fabry-Perot cavities. Modeling predicts coupling rates g/(2*pi) exceeding 700 MHz and critical atom numbers approaching 10^{-7} in optimized structures. Furthermore, preliminary experimental measurements of toroidal cavities at a wavelength of 852 nm indicate that quality factors in excess of 100 million can be obtained in a 50 micron principal diameter cavity, which w...

  18. Stellar Dynamo Models with Prominent Surface Toroidal Fields

    Science.gov (United States)

    Bonanno, Alfio

    2016-12-01

    Recent spectro-polarimetric observations of solar-type stars have shown the presence of photospheric magnetic fields with a predominant toroidal component. If the external field is assumed to be current-free it is impossible to explain these observations within the framework of standard mean-field dynamo theory. In this work, it will be shown that if the coronal field of these stars is assumed to be harmonic, the underlying stellar dynamo mechanism can support photospheric magnetic fields with a prominent toroidal component even in the presence of axisymmetric magnetic topologies. In particular, it is argued that the observed increase in the toroidal energy in low-mass fast-rotating stars can be naturally explained with an underlying αΩ mechanism.

  19. Stellar dynamo models with prominent surface toroidal fields

    CERN Document Server

    Bonanno, Alfio

    2016-01-01

    Recent spectro-polarimetric observations of solar-type stars have shown the presence of photospheric magnetic fields with a predominant toroidal component. If the external field is assumed to be current-free it is impossible to explain these observations within the framework of standard mean-field dynamo theory. In this work it will be shown that if the coronal field of these stars is assumed to be harmonic, the underlying stellar dynamo mechanism can support photospheric magnetic fields with a prominent toroidal component even in the presence of axisymmetric magnetic topologies. In particular it is argued that the observed increase in the toroidal energy in low mass fast rotating stars can be naturally explained with an underlying $\\alpha\\Omega$ mechanism.

  20. Compact Toroid Propagation in a Magnetized Drift Tube

    Science.gov (United States)

    Horton, Robert D.; Baker, Kevin L.; Hwang, David Q.; Evans, Russell W.

    2000-10-01

    Injection of a spheromak-like compact toroid (SCT) plasma into a toroidal plasma confinement device may require the SCT to propagate through a drift tube region occupied by a pre-existing magnetic field. This field is expected to extert a retarding force on the SCT, but may also result in a beneficial compression. The effects of transverse and longitudinal magnetic fields will be measured using the CTIX compact-toroid injector, together with a fast framing camera with an axial view of the formation, coaxial, and drift-tube regions. In the case of longitudinal magnetic field, comparisons will be made with the predictions of two-dimensional numerical simulation. The use of localized magnetic field to reduce plasma bridging of the insulating gap will also be investigated.

  1. Vlasov tokamak equilibria with shearad toroidal flow and anisotropic pressure

    CERN Document Server

    Kuiroukidis, Ap; Tasso, H

    2015-01-01

    By choosing appropriate deformed Maxwellian ion and electron distribution functions depending on the two particle constants of motion, i.e. the energy and toroidal angular momentum, we reduce the Vlasov axisymmetric equilibrium problem for quasineutral plasmas to a transcendental Grad-Shafranov-like equation. This equation is then solved numerically under the Dirichlet boundary condition for an analytically prescribed boundary possessing a lower X-point to construct tokamak equilibria with toroidal sheared ion flow and anisotropic pressure. Depending on the deformation of the distribution functions these steady states can have toroidal current densities either peaked on the magnetic axis or hollow. These two kinds of equilibria may be regarded as a bifurcation in connection with symmetry properties of the distribution functions on the magnetic axis.

  2. Efficiency of Wave-Driven Rigid Body Rotation Toroidal Confinement

    CERN Document Server

    Rax, J -M; Fisch, N J

    2016-01-01

    The compensation of vertical drifts in toroidal magnetic fields through a wave-driven poloidal rotation is compared to compensation through the wave driven toroidal current generation to support the classical magnetic rotational transform. The advantages and drawbacks associated with the sustainment of a radial electric field are compared with those associated with the sustainment of a poloidal magnetic field both in terms of energy content and power dissipation. The energy content of a radial electric field is found to be smaller than the energy content of a poloidal magnetic field for a similar set of orbits. The wave driven radial electric field generation efficiency is similarly shown, at least in the limit of large aspect ratio, to be larger than the efficiency of wave-driven toroidal current generation.

  3. Polar Cap Retreat

    Science.gov (United States)

    2004-01-01

    13 August 2004 This red wide angle Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC) image shows a view of the retreating seasonal south polar cap in the most recent spring in late 2003. Bright areas are covered with frost, dark areas are those from which the solid carbon dioxide has sublimed away. The center of this image is located near 76.5oS, 28.2oW. The scene is large; it covers an area about 250 km (155 mi) across. The scene is illuminated by sunlight from the upper left.

  4. Reevaluation of the Braginskii viscous force for toroidal plasma

    CERN Document Server

    Johnson, Robert W

    2009-01-01

    The model by Braginskii for the viscous stress tensor is used to determine the shear and gyroviscous forces acting within a toroidally confined plasma. Comparison is made to previous evaluations which contain an inconsistent treatment of the radial derivative and neglect the effect of the pitch angle. A radial gyroviscous force is found to survive the limit of constant density and rigid toroidal rotation of the flux surface, and a radial shear viscous force may develop for sufficient vertical asymmetry to the ion velocity profile.

  5. Comparative study between toroidal coordinates and the magnetic dipole field

    CERN Document Server

    Chávez-Alarcón, Esteban

    2012-01-01

    There is a similar behaviour between the toroidal coordinates and the dipole magnetic field produced by a circular loop. In this work we evaluate up to what extent the former can be used as a representation of the latter. While the tori in the toroidal coordinates have circular cross sections, those of the circular loop magnetic field are nearly elliptical ovoids, but they are very similar for large aspect ratios.The centres of the latter displace from the axis faster than the former. By making a comparison between tori of similar aspect ratios, we find quantitative criteria to evaluate the accuracy of the approximation.

  6. Development and verification of printed circuit board toroidal transformer model

    DEFF Research Database (Denmark)

    Pejtersen, Jens; Mønster, Jakob Døllner; Knott, Arnold

    2013-01-01

    by comparing calculated parameters with 3D finite element simulations and experimental measurement results. The developed transformer model shows good agreement with the simulated and measured results. The model can be used to predict the parameters of printed circuit board toroidal transformer configurations......An analytical model of an air core printed circuit board embedded toroidal transformer configuration is presented. The transformer has been developed for galvanic isolation of very high frequency switch-mode dc-dc power converter applications. The theoretical model is developed and verified...

  7. Toroidal vortices as a solution to the dust migration problem

    CERN Document Server

    Loren-Aguilar, Pablo

    2015-01-01

    In an earlier letter, we reported that dust settling in protoplanetary discs may lead to a dynamical dust-gas instability that produces global toroidal vortices. In this letter, we investigate the evolution of a dusty protoplanetary disc with two different dust species (1 mm and 50 cm dust grains), under the presence of the instability. We show how toroidal vortices, triggered by the interaction of mm grains with the gas, stop the radial migration of metre-sized dust, potentially offering a natural and efficient solution to the dust migration problem.

  8. Ion temperature gradient modes in toroidal helical systems

    Energy Technology Data Exchange (ETDEWEB)

    Kuroda, T. [Graduate University for Advanced Studies, Toki, Gifu (Japan); Sugama, H.; Kanno, R.; Okamoto, M.

    2000-04-01

    Linear properties of ion temperature gradient (ITG) modes in helical systems are studied. The real frequency, growth rate, and eigenfunction are obtained for both stable and unstable cases by solving a kinetic integral equation with proper analytic continuation performed in the complex frequency plane. Based on the model magnetic configuration for toroidal helical systems like the Large Helical Device (LHD), dependences of the ITG mode properties on various plasma equilibrium parameters are investigated. Particularly, relative effects of {nabla}B-curvature drifts driven by the toroidicity and by the helical ripples are examined in order to compare the ITG modes in helical systems with those in tokamaks. (author)

  9. 3D Projection Installations

    DEFF Research Database (Denmark)

    Halskov, Kim; Johansen, Stine Liv; Bach Mikkelsen, Michelle

    2014-01-01

    Three-dimensional projection installations are particular kinds of augmented spaces in which a digital 3-D model is projected onto a physical three-dimensional object, thereby fusing the digital content and the physical object. Based on interaction design research and media studies, this article...... contributes to the understanding of the distinctive characteristics of such a new medium, and identifies three strategies for designing 3-D projection installations: establishing space; interplay between the digital and the physical; and transformation of materiality. The principal empirical case, From...... Fingerplan to Loop City, is a 3-D projection installation presenting the history and future of city planning for the Copenhagen area in Denmark. The installation was presented as part of the 12th Architecture Biennale in Venice in 2010....

  10. Biggest semiconductor installed

    CERN Multimedia

    2008-01-01

    Scientists and technicians at the European Laboratory for Particle Physics, commonly known by its French acronym CERN (Centre Europen pour la Recherche Nuclaire), have completed the installation of the largest semiconductor silicon detector.

  11. Effects of Toroidal Rotation Sshear on Toroidicity-induced Alfven Eigenmodes in the National Spherical Torus Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Podesta, M; Fredrickson, E D; Gorelenkov, N N; LeBlanc, B P; Heidbrink, W W; Crocker, N A; Kubota, S

    2010-08-19

    The effects of a sheared toroidal rotation on the dynamics of bursting Toroidicity-induced Alfven eigenmodes are investigated in neutral beam heated plasmas on the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 40 557 (2000)]. The modes have a global character, extending over most of the minor radius. A toroidal rotation shear layer is measured at the location of maximum drive for the modes. Contrary to results from other devices, no clear evidence of increased damping is found. Instead, experiments with simultaneous neutral beam and radio-frequency auxiliary heating show a strong correlation between the dynamics of the modes and the instability drive. It is argued that kinetic effects involving changes in the mode drive and damping mechanisms other than rotation shear, such as continuum damping, are mostly responsible for the bursting dynamics of the modes.

  12. Transport and Dynamics in Toroidal Fusion Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sovinec, Carl [Univ. of Wisconsin, Madison, WI (United States)

    2016-09-07

    The study entitled, "Transport and Dynamics in Toroidal Fusion Systems," (TDTFS) applied analytical theory and numerical computation to investigate topics of importance to confining plasma, the fourth state of matter, with magnetic fields. A central focus of the work is how non-thermal components of the ion particle distribution affect the "sawtooth" collective oscillation in the core of the tokamak magnetic configuration. Previous experimental and analytical research had shown and described how the oscillation frequency decreases and amplitude increases, leading to "monster" or "giant" sawteeth, when the non-thermal component is increased by injecting particle beams or by exciting ions with imposed electromagnetic waves. The TDTFS study applied numerical computation to self-consistently simulate the interaction between macroscopic collective plasma dynamics and the non-thermal particles. The modeling used the NIMROD code [Sovinec, Glasser, Gianakon, et al., J. Comput. Phys. 195, 355 (2004)] with the energetic component represented by simulation particles [Kim, Parker, Sovinec, and the NIMROD Team, Comput. Phys. Commun. 164, 448 (2004)]. The computations found decreasing growth rates for the instability that drives the oscillations, but they were ultimately limited from achieving experimentally relevant parameters due to computational practicalities. Nonetheless, this effort provided valuable lessons for integrated simulation of macroscopic plasma dynamics. It also motivated an investigation of the applicability of fluid-based modeling to the ion temperature gradient instability, leading to the journal publication [Schnack, Cheng, Barnes, and Parker, Phys. Plasmas 20, 062106 (2013)]. Apart from the tokamak-specific topics, the TDTFS study also addressed topics in the basic physics of magnetized plasma and in the dynamics of the reversed-field pinch (RFP) configuration. The basic physics work contributed to a study of two-fluid effects on interchange dynamics, where

  13. Installing the World

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    THE art of installation is an art about concept," explains Qing Qing Chen. The artist wants her audience to look at the development of aesthetics from a pluralistic angle on life. Unlike the expressive format of "art in the frame," the art of installation belongs to the category of "non-framed art." The choice of materials used is as important to expression as the creator’s ideas. Whereas only certain materials can be

  14. Installation af opvaskemaskine

    DEFF Research Database (Denmark)

    Christiansen, J.; Skibstrup Eriksen, S.; Nielsen, F.

    Denne SBI-anvisning er et led i en serie om modernisering af installationerne i den ældre boligmasse. Den henvender sig til både beboere, husejere, VVS-installatører og andre interesserede. Anvisningen indeholder almene afsnit om valg og placering af opvaskemaskine, sagsforløb ved installation......, forhold til myndigheder, priser, finansieringsmuligheder m.m. Anvisningen indeholder endvidere tekniske afsnit om vandinstallation, afløb og elinstallation i forbindelse med installation af opvaskemaskine....

  15. Complex biopower installation

    Directory of Open Access Journals (Sweden)

    Tirshu M.

    2008-12-01

    Full Text Available It is presented the technological scheme of complex biopower installation for manufacture of the electric power, hot water and gas at use as raw material of manure, birds dung and firm organic waste products. The suggested technical solution provides practically 100 % use of energy of burnt gas due to the introduced feedback between power station and a bioreactor. Recommendations for the best use of installation in Republics Moldova are developed as well.

  16. Controlling the toroidal excitations in metamaterials for high-Q response

    CERN Document Server

    Fan, Yuancheng; Fu, Quanhong; Wei, Zeyong; Li, Hongqiang

    2016-01-01

    The excitation of toroidal multipoles in metamaterials was investigated for high-Q response at a subwavelength scale. In this study, we explored the optimization of toroidal excitations in a planar metamaterial comprised of asymmetric split ring resonators (ASRRs). It was found that the scattering power of toroidal dipole can be remarkably strengthened by adjusting the characteristic parameter of ASRRs: asymmetric factor. Interestingly, the improvement in toroidal excitation accompanies increasing of the Q-factor of the toroidal metamaterial, it is shown that both the scattering power of toroidal dipole and the Q-factor were increased near one order by changing the asymmetric factor of ASRRs. The optimization in excitation of toroidal multipoles provide opportunity to further increase the Q-factor of toroidal metamaterial and boost light-matter interactions at the subwavelength scale for potential applications in low-power nonlinear processing and sensitive photonic applications.

  17. Stability of toroidal magnetic fields in stellar interiors

    CERN Document Server

    Ibañez-Mejia, Juan C

    2015-01-01

    We present 3D MHD simulations of purely toroidal and mixed poloidal-toroidal magnetic field configurations to study the behavior of the Tayler instability. For the first time the simultaneous action of rotation and magnetic diffusion are taken into account and the effects of a poloidal field on the dynamic evolution of unstable toroidal magnetic fields is included. In the absence of diffusion, fast rotation (rotation rate compared to Alfv\\'en frequency) is able to suppress the instability when the rotation and magnetic axes are aligned and when the radial field strength gradient p 1.5, rapid rotation does not suppress the instability but instead introduces a damping factor to the growth rate in agreement with the analytic predictions. For the mixed poloidal-toroidal fields we find an unstable axisymmetric mode, not predicted analytically, right at the stability threshold for the non-axisymmetric modes; it has been argued that an axisymmetric mode is necessary for the closure of the Tayler-Spruit dynamo loop.

  18. First ATLAS Barrel Toroid coil casing arrives at CERN

    CERN Multimedia

    2002-01-01

    The first of eight 25-metre long coil casings for the ATLAS experiment's barrel toroid magnet system arrived at CERN on Saturday 2 March by road from Heidelberg. This structure will be part of the largest superconducting toroid magnet ever made.   The first coil casing for the toroidal magnets of Atlas arrives at Building 180. This is the start of an enormous three-dimensional jigsaw puzzle. Each of the eight sets of double pancake coils will be housed inside aluminium coil casings, which in turn will be held inside a stainless steel vacuum vessel. A huge construction, the casing that arrived at CERN measures 25 metres in length and 5 metres in width. It weighs 20 tones. And this is just the beginning of the toroid jigsaw: by early April a batch of four double pancake coils, which altogether weighs 65 tones, will arrive from Ansaldo in Italy. The first vacuum vessel will also be arriving from Felguera in Spain this month. It will take about two years for all these 25 m long structures of casings, coils a...

  19. Approximations for the natural logarithm from solenoid-toroid correspondence

    CERN Document Server

    Semiz, Ibrahim

    2015-01-01

    It seems reasonable that a toroid can be thought of approximately as a solenoid bent into a circle. The correspondence of the inductances of these two objects gives an approximation for the natural logarithm in terms of the average of two numbers. Different ways of averaging give different approximants. They are expressions simpler than Taylor polynomials, and are meaningful over a wider domain.

  20. Toroidal equilibrium in an iron-core reversed field pinch

    Energy Technology Data Exchange (ETDEWEB)

    Miller, G.

    1984-04-01

    An analytical theory of toroidal equilibrium in the ZT-40M reversed field pinch is obtained, including effects of iron cores and resistive shell. The iron cores alter the form of the equilibrium condition and cause the equilibrium to be unstable on the shell resistive time scale.

  1. Theory of the M = 1 Kink Mode in Toroidal Plasma

    NARCIS (Netherlands)

    de Blank, H. J.; Schep, T. J.

    1991-01-01

    The energy principle of ideal magnetohydrodynamics (MHD) is used to study the ideal MHD stability of the m = 1 internal kink mode in a toroidal plasma. The equilibrium configurations that are considered allow for a broad region where the safety factor q is close to unity. This region may extend to t

  2. Evidence of Inward Toroidal Momentum Convection in the JET Tokamak

    DEFF Research Database (Denmark)

    Tala, T.; Zastrow, K.-D.; Ferreira, J.

    2009-01-01

    Experiments have been carried out on the Joint European Torus tokamak to determine the diffusive and convective momentum transport. Torque, injected by neutral beams, was modulated to create a periodic perturbation in the toroidal rotation velocity. Novel transport analysis shows the magnitude an...

  3. Toroidal and poloidal momentum transport studies in JET

    DEFF Research Database (Denmark)

    Tala, T.; Andrew, Y.; Crombe, K.

    2007-01-01

    This paper reports on the recent studies of toroidal and poloidal momentum transport in JET. The ratio of the global energy confinement time to the momentum confinement is found to be close to tau(E)/tau(phi) = 1 except for the low density or low collisionality discharges where the ratio is tau(E...

  4. ATLAS-Lowering the first Barrel Toroid coil

    CERN Multimedia

    CERN Audiovisual Unit

    2004-01-01

    Cranes lowered the first of ATLAS's eight Barrel Toroid coils into the cavern. The part is 25 meters long and the cranes had to hold the 100 tonne coil at a sharp angle while it passed through the 18-meter diameter vertical shaft into the cavern. Then they laid the magnet to a horizontal robust platform. Images from Camera 2

  5. ATLAS-Lowering the first Barrel Toroid coil

    CERN Multimedia

    2004-01-01

    Cranes lowered the first of ATLAS's eight Barrel Toroid coils into the cavern. The part is 25 metres long and the cranes had to hold the 100 tonne coil at a sharp angle while it passed through the 18-metre diameter vertical shaft into the cavern. Then they laid the magnet to a horisontal robust platform. Images from Camera 1

  6. Plasma Processes : Minimum dissipative relaxed states in toroidal plasmas

    Indian Academy of Sciences (India)

    R Bhattacharyya; M S Janaki; B Dasgupta

    2000-11-01

    Relaxation of toroidal discharges is described by the principle of minimum energy dissipation together with the constraint of conserved global helicity. The resulting Euler-Lagrange equation is solved in toroidal coordinates for an axisymmetric torus by expressing the solutions in terms of Chandrasekhar-Kendall (C-K) eigenfunctions analytically continued in the complex domain. The C-K eigenfunctions are obtained as hypergeometric functions that are solutions of scalar Helmholtz equation in toroidal coordinates in the large aspect-ratio approximation. Equilibria are constructed by assuming the current to vanish at the edge of plasma. For the = 0; = 0 ( and are the poloidal and toroidal mode numbers respectively) relaxed states, the magnetic field, current, (safety factor) and pressure profiles are calculated for a given value of aspect-ratio of the torus and for different values of the eigenvalue 0. The new feature of the present model is that solutions allow for both tokamak as well as RFP-like behaviour with increase in the values of 0, which is related directly to volt-sec in the experiment.

  7. Flat-band assembly for toroidal transformer cores

    Science.gov (United States)

    Mclyman, W. T.

    1973-01-01

    Toroidal transformer cores are often banded together by means of strap. Spot welds secure strap. Proper tension is obtained by use of special fixture in conjunction with winding of wire which is placed temporarily on core; winding is excited by dc current to hold core halves together magnetically during alignment.

  8. Barrel Toroid fully charged to nominal field, and it works!

    CERN Document Server

    Herman ten Kate

    After a few weeks of testing up to intermediate currents, finally, on Thursday evening November 9, the current in the Barrel Toroid was pushed up to its nominal value of 20500 A and even 500 A beyond this value to prove that we have some margin. It went surprisingly well. Of course, the 8 coils forming the toroid were already tested individually at the surface but still, some surprise may have come from those parts added to the toroid in the cavern for the first time like the 8 cryoring sections linking the coils as well as the valve box at the bottom in sector 13 regulating the helium flow or the current lead cryostat on the top in sector 5. No training quenches, nothing to worry about, and the test was concluded with a fast dump triggered at 00:40 in the very early morning of November 10. (left) The toroid current during the evening and night of November 9. (right) The test crew oscillated between fear and hope while looking at the control panels as the current approached 21kA. Big relief was in the...

  9. Homogeneous Construction of the Toroidal Lie Algebra of Type A1

    Institute of Scientific and Technical Information of China (English)

    Haifeng Lian; Cui Chen; Qinzhu Wen

    2007-01-01

    In this paper,we consider an analogue of the level two homogeneous construc-tion of the affine Kac-Moody algebra A1(1) by vertex operators.We construct modules for the toroidal Lie algebra and the extended toroidal Lie algebra of type A1.We also prove that the module is completely reducible for the extended toroidal Lie algebra.

  10. Development of Gasless Pyrotechnic Cap

    Science.gov (United States)

    1980-05-01

    beam cathode ray oscillo- scope. The caps were ignited by removing the safety pin . This also triggered the oscilloscope. The change in pressure inside...sensitivity. STRIKER SAFETY PIN PERCUSSION CAP FIXED VOLUME / ;PRESSURE TRANSDUCER TO C.R.O. FIG. 8 - Device used to determine pressure time

  11. Toroidal modeling of plasma response to RMP fields in ITER

    Science.gov (United States)

    Li, L.; Liu, Y. Q.; Wang, N.; Kirk, A.; Koslowski, H. R.; Liang, Y.; Loarte, A.; Ryan, D.; Zhong, F. C.

    2017-04-01

    A systematic numerical study is carried out, computing the resistive plasma response to the resonant magnetic perturbation (RMP) fields for ITER plasmas, utilizing the toroidal code MARS-F (Liu et al 2000 Phys. Plasmas 7 3681). A number of factors are taken into account, including the variation of the plasma scenarios (from 15 MA Q = 10 inductive scenario to the 9 MA Q = 5 steady state scenario), the variation of the toroidal spectrum of the applied fields (n = 1, 2, 3, 4, with n being the toroidal mode number), the amplitude and phase variation of the currents in three rows of the RMP coils as designed for ITER, and finally a special case of mixed toroidal spectrum between the n = 3 and n = 4 RMP fields. Two-dimensional parameter scans, for the edge safety factor and the coil phasing between the upper and lower rows of coils, yield ‘optimal’ curves that maximize a set of figures of merit, that are defined in this work to measure the plasma response. Other two-dimensional scans of the relative coil current phasing among three rows of coils, at fixed coil currents amplitude, reveal a single optimum for each coil configuration with a given n number, for the 15 MA ITER inductive plasma. On the other hand, scanning of the coil current amplitude, at fixed coil phasing, shows either synergy or cancellation effect, for the field contributions between the off-middle rows and the middle row of the RMP coils. Finally, the mixed toroidal spectrum, by combining the n = 3 and the n = 4 RMP field, results in a substantial local reduction of the amplitude of the plasma surface displacement.

  12. Status of Net Metering: Assessing the Potential to Reach Program Caps

    Energy Technology Data Exchange (ETDEWEB)

    Heeter, J.; Gelman, R.; Bird, L.

    2014-09-01

    Several states are addressing the issue of net metering program caps, which limit the total amount of net metered generating capacity that can be installed in a state or utility service territory. In this analysis, we examine net metering caps to gain perspective on how long net metering will be available in various jurisdictions under current policies. We also surveyed state practices and experience to understand important policy design considerations.

  13. Status of Net Metering: Assessing the Potential to Reach Program Caps (Poster)

    Energy Technology Data Exchange (ETDEWEB)

    Heeter, J.; Bird, L.; Gelman, R.

    2014-10-01

    Several states are addressing the issue of net metering program caps, which limit the total amount of net metered generating capacity that can be installed in a state or utility service territory. In this analysis, we examine net metering caps to gain perspective on how long net metering will be available in various jurisdictions under current policies. We also surveyed state practices and experience to understand important policy design considerations.

  14. Python Introduction and Installation

    Directory of Open Access Journals (Sweden)

    William J. Turkel

    2012-07-01

    Full Text Available This first lesson in our section on dealing with Online Sources is designed to get you and your computer set up to start programming. We will focus on installing the relevant software – all free and reputable – and finally we will help you to get your toes wet with some simple programming that provides immediate results. In this opening module you will install the Python programming language, the Beautiful Soup HTML/XML parser, and a text editor. Screencaps provided here come from Komodo Edit, but you can use any text editor capable of working with Python. Here’s a list of other options: Python Editors. Once everything is installed, you will write your first programs, “Hello World” in Python and HTML.

  15. Electrical installation technology

    CERN Document Server

    Neidle, Michael

    1982-01-01

    Electrical Installation Technology, Third Edition covers the wide range of subjects that come under the headings of electrical science, installations, and regulations. The book discusses electromagnetism; inductance; static electricity; d.c. circuits; voltage drop and current rating; distribution; and wiring techniques. The text also describes o.c. motors and generators; a.c. motors, transformers; power-factor improvement; earthing and earth-leakage protection; testing; illumination; and the general principles of temperature and heat. Communication systems and equipment; electronics; and site

  16. Electrical installations technology

    CERN Document Server

    Whitfield, J F

    1968-01-01

    Electrical Installations Technology covers the syllabus of the City and Guilds of London Institute course No. 51, the "Electricians B Certificate”. This book is composed of 15 chapters that deal with basic electrical science and electrical installations. The introductory chapters discuss the fundamentals and basic electrical principles, including the concept of mechanics, heat, magnetic fields, electric currents, power, and energy. These chapters also explore the atomic theory of electric current and the electric circuit, conductors, and insulators. The subsequent chapter focuses on the chemis

  17. Observation of Fano resonance and classical analog of electromagnetically induced transparency in toroidal metamaterials

    Energy Technology Data Exchange (ETDEWEB)

    Han, Song; Yang, Helin [College of Physical Science and Technology, Central China Normal University, Wuhan (China); Cong, Lonqing; Singh, Ranjan [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore (Singapore); Centre for Disruptive Photonic Technologies, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore (Singapore); Gao, Fei [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore (Singapore)

    2016-05-15

    Toroidal multipoles have recently been explored in various scientific communities, ranging from atomic and molecular physics, electrodynamics, and solid-state physics to biology. Here we experimentally and numerically demonstrate a three-dimensional toroidal metamaterial where two different toroidal dipoles along orthogonal directions have been observed. The chosen toroidal metamaterial also simultaneously supports Fano resonance and the classical analog of electromagnetically induced transparency (EIT) phenomena in the transmission spectra that originate from the electric-toroidal dipole and electric-magnetic dipole destructive interference. The intriguing properties of the toroidal resonances may open up avenues for applications in toroidal moments generator, sensing and slow-light devices. (copyright 2016 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Reevaluation of the Braginskii viscous force for toroidal plasma

    Science.gov (United States)

    Johnson, Robert W.

    2011-12-01

    The model by Braginskii [1] (Braginskii, S. I. 1965 Transport processes in plasma. In: Review of Plasma Physics, Vol. 1 (ed. M.A. Leontovich). New York, NY: Consultants Bureau, pp. 205-311) for the viscous stress tensor is used to determine the shear and gyroviscous forces acting within a toroidally confined plasma. Comparison is made to a previous evaluation, which contains an inconsistent treatment of the radial derivative and neglects the effect of the pitch angle. Parallel viscosity contributes a radial shear viscous force, which may develop for sufficient vertical asymmetry to the ion velocity profile. An evaluation is performed of this radial viscous force for a tokamak near equilibrium, which indicates qualitative agreement between theory and measurement for impure plasma discharges with strong toroidal flow.

  19. Modelling of density limit phenomena in toroidal helical plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Kimitaka [National Inst. for Fusion Science, Toki, Gifu (Japan); Itoh, Sanae-I. [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics; Giannone, Louis [EURATOM-IPP Association, Max Planck Institut fuer Plasmaphysik, Garching (Germany)

    2001-11-01

    The physics of density limit phenomena in toroidal helical plasmas based on an analytic point model of toroidal plasmas is discussed. The combined mechanism of the transport and radiation loss of energy is analyzed, and the achievable density is derived. A scaling law of the density limit is discussed. The dependence of the critical density on the heating power, magnetic field, plasma size and safety factor in the case of L-mode energy confinement is explained. The dynamic evolution of the plasma energy and radiation loss is discussed. Assuming a simple model of density evolution, of a sudden loss of density if the temperature becomes lower than critical value, then a limit cycle oscillation is shown to occur. A condition that divides the limit cycle oscillation and the complete radiation collapse is discussed. This model seems to explain the density limit oscillation that has been observed on the Wendelstein 7-AS (W7-AS) stellarator. (author)

  20. Modelling of density limit phenomena in toroidal helical plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, K. [National Inst. for Fusion Science, Toki, Gifu (Japan); Itoh, S.-I. [Kyushu Univ., Fukuoka (Japan). Research Inst. for Applied Mechanics; Giannone, L. [Max Planck Institut fuer Plasmaphysik, EURATOM-IPP Association, Garching (Germany)

    2000-03-01

    The physics of density limit phenomena in toroidal helical plasmas based on an analytic point model of toroidal plasmas is discussed. The combined mechanism of the transport and radiation loss of energy is analyzed, and the achievable density is derived. A scaling law of the density limit is discussed. The dependence of the critical density on the heating power, magnetic field, plasma size and safety factor in the case of L-mode energy confinement is explained. The dynamic evolution of the plasma energy and radiation loss is discussed. Assuming a simple model of density evolution, of a sudden loss of density if the temperature becomes lower than critical value, then a limit cycle oscillation is shown to occur. A condition that divides the limit cycle oscillation and the complete radiation collapse is discussed. This model seems to explain the density limit oscillation that has been observed on the W7-AS stellarator. (author)

  1. Experimental investigation of transitional flow in a toroidal pipe

    CERN Document Server

    Kühnen, J; Hof, B; Kuhlmann, H

    2015-01-01

    The flow instability and further transition to turbulence in a toroidal pipe (torus) with curvature (tube-to-coiling diameter) 0.049 is investigated experimentally. The flow inside the toroidal pipe is driven by a steel sphere fitted to the inner pipe diameter. The sphere is moved with constant azimuthal velocity from outside the torus by a moving magnet. The experiment is designed to investigate curved pipe flow by optical measurement techniques. Using stereoscopic particle image velocimetry, laser Doppler velocimetry and pressure drop measurements, the flow is measured for Reynolds numbers ranging from 1000 to 15000. Time- and space-resolved velocity fields are obtained and analysed. The steady axisymmetric basic flow is strongly influenced by centrifugal effects. On an increase of the Reynolds number we find a sequence of bifurcations. For Re=4075 a supercritical bifurcation to an oscillatory flow is found in which waves travel in the streamwise direction with a phase velocity slightly faster than the mean...

  2. Initial value problem of the toroidal ion temperature gradient mode

    Energy Technology Data Exchange (ETDEWEB)

    Kuroda, T.; Sugama, H.; Kanno, R.; Okamoto, M. [National Inst. for Fusion Science, Toki, Gifu (Japan); Horton, W.

    1998-06-01

    The initial value problem of the toroidal ion temperature gradient mode is studied based on the Laplace transform of the ion gyrokinetic equation and the electron Boltzmann relation with the charge neutrality condition. Due to the toroidal magnetic drift, the Laplace-transformed density and potential perturbations have a branch cut as well as poles on the complex-frequency plane. The inverse Laplace transform shows that the temporal evolution of the density and potential perturbations consists of the normal modes and the continuum mode, which correspond to contributions from the poles and the branch cut, respectively. The normal modes have exponential time dependence with the eigenfrequencies determined by the dispersion relation while the continuum mode shows power-law decay oscillation. For the stable case, the long-time asymptotic behavior of the potential and density perturbations is dominated by the continuum mode which decays slower than the normal modes. (author)

  3. Low-frequency fluctuations in a pure toroidal magnetized plasma

    Indian Academy of Sciences (India)

    P K Sharma; R Singh; D Bora

    2009-12-01

    A magnetized, low- plasma in pure toroidal configuration is formed and extensively studied with ion mass as control parameter. Xenon, krypton and argon plasmas are formed at a fixed toroidal magnetic field of 0.024 T, with a peak density of ∼ 1011 cm-3, ∼ 4 × 1010 cm-3 and ∼ 2 × 1010 cm−3 respectively. The experimental investigation of time-averaged plasma parameter reveals that their profiles remain insensitive to ion mass and suggests that saturated slab equilibrium is obtained. Low-frequency (LF) coherent fluctuations ( < ci) are observed and identified as flute modes. Here ci represents ion cyclotron frequency. Our results indicate that these modes get reduced with ion mass. The frequency of the fluctuating mode decreases with increase in the ion mass. Further, an attempt has been made to discuss the theory of flute modes to understand the relevance of some of our experimental observations.

  4. Precession of Toroidally Passing Particles in Tokamaks and Spherical Tori

    Energy Technology Data Exchange (ETDEWEB)

    Ya.I. Kolesnichenko; R.B.White; Yu.V. Yakovenko

    2003-01-30

    The toroidal precession of the well-circulating particles and particles that are passing toroidally but trapped poloidally is studied. Expressions for the precession frequency, which are convenient for practical use, are obtained and analyzed. It is found that the key parameters that determine the magnitude and the direction of the precession velocity are the plasma elongation, the magnitudes and profiles of the safety factor and beta defined as the ratio of the local plasma pressure to the magnetic field pressure at the magnetic axis. An important role of the ''paramagnetic'' precession in highly elongated plasmas is revealed. The analysis carried out is based on the obtained expressions for the equilibrium magnetic field strength and the field line curvature.

  5. ATLAS barrel toroid integration and test area in building 180

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    The ATLAS barrel toroid system consists of eight coils, each of axial length 25.3 m, assembled radially and symmetrically around the beam axis. The coils are of a flat racetrack type with two 'double-pancake' windings made of 20.5 kA aluminium-stabilized niobium-titanium superconductor. The barrel toroid is being assembled in building 180 on the Meyrin site. In the first phase of assembly, the coils are packed into their aluminium-alloy casing. These photos show the double-pancake coils from ANSALDO and the coil casings from ALSTOM. In the foreground is the tooling from COSMI used to turn over the coil casings during this first phase. In the right background is the yellow lifting gantry manufactured at JINR-Dubna, Russia which will transport the coil casings to a heating table for prestressing. Two test benches with magnetic mirror are also visible.

  6. Quasars a supermassive rotating toroidal black hole interpretation

    CERN Document Server

    Spivey, R J

    2000-01-01

    A supermassive rotating toroidal black hole (TBH) is proposed as the fundamental structure of quasars and other jet-producing active galactic nuclei. Rotating protogalaxies gather matter from the central gaseous region leading to the birth of massive toroidal stars whose internal nuclear reactions proceed very rapidly. Once the nuclear fuel is spent, gravitational collapse produces a slender ring-shaped TBH remnant. These events are typically the first supernovae of the host galaxies. Given time the TBH mass increases through continued accretion by several orders of magnitude, the event horizon swells whilst the central aperture shrinks. The difference in angular velocities between the accreting matter and the TBH induces a magnetic field that is strongest in the region of the central aperture and innermost ergoregion. Due to the presence of negative energy states when such a gravitational vortex is immersed in an electromagnetic field, circumstances are near ideal for energy extraction via non-thermal radiat...

  7. Radial Eigenmodes for a Toroidal Waveguide with Rectangular Cross Section

    Energy Technology Data Exchange (ETDEWEB)

    Rui Li

    2012-07-01

    In applying mode expansion to solve the CSR impedance for a section of toroidal vacuum chamber with rectangular cross section, we identify the eigenvalue problem for the radial eigenmodes which is different from that for cylindrical structures. In this paper, we present the general expressions of the radial eigenmodes, and discuss the properties of the eigenvalues on the basis of the Sturm-Liouville theory.

  8. Miniature anastigmatic spectrometer design with a concave toroidal mirror.

    Science.gov (United States)

    Dong, Jianing; Chen, He; Zhang, Yinchao; Chen, Siying; Guo, Pan

    2016-03-01

    An advanced optical design for a low-cost and astigmatism-corrected spectrometer with a high resolution is presented. The theory and method of astigmatism correction are determined with the use of a concave toroidal mirror. The performances of a modified spectrometer and a traditional spectrometer are compared, and the analysis is verified. Experimentally, the limiting resolution of our spectrometer is 0.1 nm full width at half-maximum, as measured for 579.1 nm.

  9. ATLAS - End-Cap calorimeter

    CERN Multimedia

    2006-01-01

    The End-cap calorimeter was moved with the help of the rails and this calorimeter will measure the energy of particles close to the beam axis when protons collide. Cooling is important for maximum detector efficiency.

  10. 3D toroidal physics: Testing the boundaries of symmetry breakinga)

    Science.gov (United States)

    Spong, Donald A.

    2015-05-01

    Toroidal symmetry is an important concept for plasma confinement; it allows the existence of nested flux surface MHD equilibria and conserved invariants for particle motion. However, perfect symmetry is unachievable in realistic toroidal plasma devices. For example, tokamaks have toroidal ripple due to discrete field coils, optimized stellarators do not achieve exact quasi-symmetry, the plasma itself continually seeks lower energy states through helical 3D deformations, and reactors will likely have non-uniform distributions of ferritic steel near the plasma. Also, some level of designed-in 3D magnetic field structure is now anticipated for most concepts in order to provide the plasma control needed for a stable, steady-state fusion reactor. Such planned 3D field structures can take many forms, ranging from tokamaks with weak 3D edge localized mode suppression fields to stellarators with more dominant 3D field structures. This motivates the development of physics models that are applicable across the full range of 3D devices. Ultimately, the questions of how much symmetry breaking can be tolerated and how to optimize its design must be addressed for all fusion concepts. A closely coupled program of simulation, experimental validation, and design optimization is required to determine what forms and amplitudes of 3D shaping and symmetry breaking will be compatible with the requirements of future fusion reactors.

  11. Toroidal Continuously Variable Transmission Systems: Terminology and Present Studies

    Directory of Open Access Journals (Sweden)

    Ahmet YILDIZ

    2014-04-01

    Full Text Available The use of continuously variable transmission systems in many different areas such as aerospace, robotics, machinery and automotive industries as an alternative to conventional speed changers with constant ratio becomes widely.Especially in the automotive industry, these systems have been used increasingly, since they enable that internal combustion engines in vehicles run at optimal speeds, and consequently provide considerable fuel savings and therefore lower emission values and also they provide powerful acceleration and quiet working. CVT systems have several constructive variants such as belted, chained, balled, toroidal etc. In this paper, toroidal CVT systems based on elastohydrodynamic principles are concerned with, and fundamental works of last two decades in this field are reviewed. However, the relevant terminology and dynamics along with the control of these systems are briefly treated for better understanding of the literature mentioned. Attention is drawn to the lack of some significant issues in present research works, and potential future works are pointed out. This paper, to the authors’ knowledge, will be the first review on toroidal CVT systems in Turkish literature

  12. The Geometry on Smooth Toroidal Compactifications of Siegel varieties

    CERN Document Server

    Yau, Shing-Tung

    2012-01-01

    This is a part of our joint program. The purpose of this paper is to study smooth toroidal compactifications of Siegel varieties and their applications, we also try to understand the K\\"ahler-Einstein metrics on Siegel varieties through the compactifications. Let $A_{g,\\Gamma}:=H_g/\\Gamma$ be a Siegel variety, where $H_g$ is the genus-$g$ Siegel space and $\\Gamma$ is an arithmetic subgroup in $\\Aut(H_g)$. There are four aspects of this paper : 1.There is a correspondence between the category of degenerations of Abelian varieties and the category of limits of weight one Hodge structures. We show that any cusp of Siegel space $\\frak{H}_g$ can be identified with the set of certain weight one polarized mixed Hodge structures. 2.In general, the boundary of a smooth toroidal compactification $\\bar{A}_{g,\\Gamma}$ of $A_{g,\\Gamma}$ has self-intersections.For most geometric applications, we would like to have a nice toroidal compactification such that the added infinity boundary $D_\\infty =\\bar{A}_{g,\\Gamma}-A_{g,\\Gam...

  13. 3D toroidal physics: Testing the boundaries of symmetry breaking

    Energy Technology Data Exchange (ETDEWEB)

    Spong, Donald A., E-mail: spongda@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169 (United States)

    2015-05-15

    Toroidal symmetry is an important concept for plasma confinement; it allows the existence of nested flux surface MHD equilibria and conserved invariants for particle motion. However, perfect symmetry is unachievable in realistic toroidal plasma devices. For example, tokamaks have toroidal ripple due to discrete field coils, optimized stellarators do not achieve exact quasi-symmetry, the plasma itself continually seeks lower energy states through helical 3D deformations, and reactors will likely have non-uniform distributions of ferritic steel near the plasma. Also, some level of designed-in 3D magnetic field structure is now anticipated for most concepts in order to provide the plasma control needed for a stable, steady-state fusion reactor. Such planned 3D field structures can take many forms, ranging from tokamaks with weak 3D edge localized mode suppression fields to stellarators with more dominant 3D field structures. This motivates the development of physics models that are applicable across the full range of 3D devices. Ultimately, the questions of how much symmetry breaking can be tolerated and how to optimize its design must be addressed for all fusion concepts. A closely coupled program of simulation, experimental validation, and design optimization is required to determine what forms and amplitudes of 3D shaping and symmetry breaking will be compatible with the requirements of future fusion reactors.

  14. Evaluation of MerCAP for Power Plant Mercury Control

    Energy Technology Data Exchange (ETDEWEB)

    Carl Richardson

    2008-09-30

    This report is submitted to the U.S. Department of Energy National Energy Technology Laboratory (DOE-NETL) as part of Cooperative Agreement DE-FC26-03NT41993, 'Evaluation of EPRI's MerCAP{trademark} Technology for Power Plant Mercury Control'. This project has investigated the mercury removal performance of EPRI's Mercury Capture by Amalgamation Process (MerCAP{trademark}) technology. Test programs were conducted to evaluate gold-based MerCAP{trademark} at Great River Energy's Stanton Station Unit 10 (Site 1), which fired both North Dakota lignite (NDL) and Power River Basin (PRB) coal during the testing period, and at Georgia Power's Plant Yates Unit 1 (Site 2) [Georgia Power is a subsidiary of The Southern Company] which fires a low sulfur Eastern bituminous coal. Additional tests were carried out at Alabama Power's Plant Miller, which fires Powder River Basin Coal, to evaluate a carbon-based MerCAP{trademark} process for removing mercury from flue gas downstream of an electrostatic precipitator [Alabama Power is a subsidiary of The Southern Company]. A full-scale gold-based sorbent array was installed in the clean-air plenum of a single baghouse compartment at GRE's Stanton Station Unit 10, thereby treating 1/10th of the unit's exhaust gas flow. The substrates that were installed were electroplated gold screens oriented parallel to the flue gas flow. The sorbent array was initially installed in late August of 2004, operating continuously until its removal in July 2006, after nearly 23 months. The initial 4 months of operation were conducted while the host unit was burning North Dakota lignite (NDL). In November 2004, the host unit switched fuel to burn Powder River Basin (PRB) subbituminous coal and continued to burn the PRB fuel for the final 19 months of this program. Tests were conducted at Site 1 to evaluate the impacts of flue gas flow rate, sorbent plate spacing, sorbent pre-cleaning and regeneration, and spray

  15. Leadership for Sustainable Installations

    Science.gov (United States)

    2011-04-01

    way into the lexicon of the Army and installation management ( Warnock , 2009). Accordingly, the Undersecretary of the Army is the Senior...business approach, the Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection of information is estimated...needed, and completing and reviewing the collection of information . Send comments regarding this burden estimate or any other aspect of this collection

  16. Installing the ALICE detector

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    The huge iron yoke in the cavern at Point 2 in the LHC tunnel is prepared for the installation of the ALICE experiment. The yoke is being reused from the previous L3 experiment that was located at the same point during the LEP project from 1989 to 2000. ALICE will be inserted piece by piece into the cradle where it will be used to study collisions between two beams of lead ions.

  17. First ALICE detectors installed!

    CERN Document Server

    2006-01-01

    Detectors to track down penetrating muon particles are the first to be placed in their final position in the ALICE cavern. The Alice muon spectrometer: in the foreground the trigger chamber is positioned in front of the muon wall, with the dipole magnet in the background. After the impressive transport of its dipole magnet, ALICE has begun to fill the spectrometer with detectors. In mid-July, the ALICE muon spectrometer team achieved important milestones with the installation of the trigger and the tracking chambers of the muon spectrometer. They are the first detectors to be installed in their final position in the cavern. All of the eight half planes of the RPCs (resistive plate chambers) have been installed in their final position behind the muon filter. The role of the trigger detector is to select events containing a muon pair coming, for instance, from the decay of J/ or Y resonances. The selection is made on the transverse momentum of the two individual muons. The internal parts of the RPCs, made o...

  18. Comparison of human CAP and CAP2, homologs of the yeast adenylyl cyclase-associated proteins.

    Science.gov (United States)

    Yu, G; Swiston, J; Young, D

    1994-06-01

    We previously reported the identification of human CAP, a protein that is related to the Saccharomyces cerevisiae and Schizosaccharomyces pombe adenylyl cyclase-associated CAP proteins. The two yeast CAP proteins have similar functions: the N-terminal domains are required for the normal function of adenylyl cyclase, while loss of the C-terminal domains result in morphological and nutritional defects that are unrelated to the cAMP pathways. We have amplified and cloned cDNAs from a human glioblastoma library that encode a second CAP-related protein, CAP2. The human CAP and CAP2 proteins are 64% identical. Expression of either human CAP or CAP2 in S. cerevisiae cap- strains suppresses phenotypes associated with deletion of the C-terminal domain of CAP, but does not restore hyper-activation of adenylyl cyclase by RAS2val19. Similarly, expression of either human CAP or CAP2 in S. pombe cap- strains suppresses the morphological and temperature-sensitive phenotypes associated with deletion of the C-terminal domain of CAP in this yeast. In addition, expression of human CAP, but not CAP2, suppresses the propensity to sporulate due to deletion of the N-terminal domain of CAP in S. pombe. This latter observation suggests that human CAP restores normal adenylyl cyclase activity in S. pombe cap- cells. Thus, functional properties of both N-terminal and C-terminal domains are conserved between the human and S. pombe CAP proteins.

  19. Decommissioning of offshore installations

    Energy Technology Data Exchange (ETDEWEB)

    Oeen, Sigrun; Iversen, Per Erik; Stokke, Reidunn; Nielsen, Frantz; Henriksen, Thor; Natvig, Henning; Dretvik, Oeystein; Martinsen, Finn; Bakke, Gunnstein

    2010-07-01

    New legislation on the handling and storage of radioactive substances came into force 1 January 2011. This version of the report is updated to reflect this new regulation and will therefore in some chapters differ from the Norwegian version (see NEI-NO--1660). The Ministry of the Environment commissioned the Climate and Pollution Agency to examine the environmental impacts associated with the decommissioning of offshore installations (demolition and recycling). This has involved an assessment of the volumes and types of waste material and of decommissioning capacity in Norway now and in the future. This report also presents proposals for measures and instruments to address environmental and other concerns that arise in connection with the decommissioning of offshore installations. At present, Norway has four decommissioning facilities for offshore installations, three of which are currently involved in decommissioning projects. Waste treatment plants of this kind are required to hold permits under the Pollution Control Act. The permit system allows the pollution control authority to tailor the requirements in a specific permit by evaluating conditions and limits for releases of pollutants on a case-to-case basis, and the Act also provides for requirements to be tightened up in line with the development of best available techniques (BAT). The environmental risks posed by decommissioning facilities are much the same as those from process industries and other waste treatment plants that are regulated by means of individual permits. Strict requirements are intended to ensure that environmental and health concerns are taken into account. The review of the four Norwegian decommissioning facilities in connection with this report shows that the degree to which requirements need to be tightened up varies from one facility to another. The permit for the Vats yard is newest and contains the strictest conditions. The Climate and Pollution Agency recommends a number of measures

  20. Toroidal cell and battery. [storage battery for high amp-hour load applications

    Science.gov (United States)

    Nagle, W. J. (Inventor)

    1981-01-01

    A toroidal storage battery designed to handle relatively high amp-hour loads is described. The cell includes a wound core disposed within a pair of toroidal channel shaped electrodes spaced apart by nylon insulator. The shape of the case electrodes of this toroidal cell allows a first planar doughnut shaped surface and the inner cylindrical case wall to be used as a first electrode and a second planar doughnut shaped surface and the outer cylindrical case wall to be used as a second electrode. Connectors may be used to stack two or more toroidal cells together by connecting substantially the entire surface area of the first electrode of a first cell to substantially the entire surface area of the second electrode of a second cell. The central cavity of each toroidal cell may be used as a conduit for pumping a fluid through the toroidal cell to thereby cool the cell.

  1. Mineral mining installation

    Energy Technology Data Exchange (ETDEWEB)

    Plevak, L.; Weirich, W.

    1982-04-20

    A longwall mineral mining installation has a longwall conveyor and a plurality of roof support units positioned side-by-side at the goaf side of the conveyor. The hydraulic appliances of the roof support units, such as their hydraulic props, hydraulic advance rams and hydraulic control valves, are supplied with pressurized hydraulic fluid from hydraulic supply lines which run along the goaf side of the conveyor. A plurality of flat, platelike intermediate members are provided at the goaf side of the conveyor. These intermediate members are formed with internal ducts for feeding the hydraulic fluid from the supply lines to the hydraulic appliances of the roof support units.

  2. PARTICLE-HOLE NATURE OF THE LIGHT HIGH-SPIN TOROIDAL ISOMERS

    Energy Technology Data Exchange (ETDEWEB)

    Staszczak, A. [Maria Curie-Sklodowska University, Poland; Wong, Cheuk-Yin [ORNL

    2015-01-01

    Nuclei under non-collective rotation with a large angular momentum above some threshold can assume a toroidal shape. In our previous work, we showed by using cranked Skyrme Hartree Fock approach that even even, N = Z, high-K, toroidal isomeric states may have general occurrences for light nuclei with 28 < A < 52. We present here some additional results and systematics on the particle-hole nature of these high-spin toroidal isomers.

  3. Design and implementation of a multichannel millimeter wave interferometer for the Compact Toroidal Hybrid experiment

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M. C.; Hanson, J. D.; Hartwell, G. J.; Knowlton, S. F.; Maurer, D. A.; Stevenson, B. A. [Physics Department, Auburn University, Auburn, Alabama 36849 (United States)

    2012-10-15

    A three-channel 1 mm wave interferometer has been designed, assembled, and installed on the Compact Toroidal Hybrid torsatron (CTH). The interferometer design makes novel use of a subharmonic mixer for detection, which simplifies alignment. It employs a single electronically tunable source that is repetitively chirped using a sawtooth waveform of frequency up to 1 MHz. The 15.25 GHz drive oscillator is multiplied in two stages to 122 GHz before a final doubler stage brings it to 244 GHz. Local oscillator (LO) power at 122 GHz is directed through waveguide to the LO input of the subharmonic mixer of each viewing chord, simplifying alignment. Phase detection is performed by directly digitizing the amplified mixer outputs at 50 MHz and processing them with a software algorithm. Initial measurements made with the central chord of the new interferometer agree with those from the existing 4 mm system at low densities. The 1 mm system performs well in current-driven discharges reaching densities over 10{sup 19} m{sup -3}, whereas the lower frequency interferometer is found to be less reliable due to loss of fringes. This is a critical improvement for experiments studying the onset, avoidance, and vacuum magnetic transform dependence of disruptions in the CTH device.

  4. Thermal and electrical joint test for the helical field coils in the Advanced Toroidal Facility

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R.L.; Johnson, R.L.

    1985-01-01

    Initial feasibility studies of a number of configurations for the Advanced Toroidal Facility (ATF) resulted in the selection of a resistive copper continuous-coil torsatron as the optimum device considering the physics program, cost, and schedule. Further conceptual design work was directed toward optimization of this configuration and, if possible, a shorter schedule. It soon became obvious that in order to shorten the schedule, a number of design and fabrication activities should proceed in parallel. This was most critical for the vacuum vessel and the helical field (HF) coils. If the HF coils were wound in place on a completed vacuum vessel, the overall schedule would be significantly (greater than or equal to12 months) longer. The approach of parallel scheduel paths requires that the HF coils be segmented into parts of less than or equal to180 of poloidal angle and that joints be made on a turn-by-turn basis when the segments are installed. It was obvious from the outset that the compact and complex geometry of the joint design presented a special challenge in the areas of reliability, assembly, maintenance, disassembly, and cost. Also, electrical, thermal, and force excursions are significant for these joints. A number of soldered, welded, brazed, electroplated, and bolted joints were evaluated. The evaluations examined fabrication feasibility and complexity, thermal-electrical performance at approximately two-thirds of the steady-state design conditions, and installation and assembly processes. Results of the thermal-electrical tests were analyzed and extrapolated to predict performance at peak design parameters. The final selection was a lap-type joint clamped with insulated bolts that pass through the winding packing. 3 refs., 4 figs.

  5. The comparative analysis of the different mechanisms of toroidal rotation in tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Sabot, R. [Association Euratom-CEA, Centre d`Etudes Nucleaires de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Parail, V. [Kurchatov Institute, Moscow (Russian Federation)

    1994-07-01

    The toroidal plasma rotation appears as one the possible mechanism for suppression of plasma turbulence. Several mechanisms are believed to contribute to the toroidal plasma rotation. The results of numerical simulation of the toroidal rotation on JET are presented, where are taken into consideration the following effects: the neoclassical viscosity due to banana and ripple trapped particles, the anomalous viscosity due to plasma turbulence, the momentum input by NBI (neutron beam injection) and ion momentum loss near the separatrix due to prompt ion losses. The NBI appeared to be the principal source of toroidal plasma rotation. 6 refs., 2 figs.

  6. The North Zealand CAP Monitor

    DEFF Research Database (Denmark)

    Nielsen, Minna; Ravn, Pernille; Notander Clausen, Lise

    Contect We describe how we developed a monitoring system for community acquired pneumonia (CAP) at North Zealand Regional hospital. We serve 310.000 inhabitants and annually around 3200 patients with CAP are admitted. As part of a program of clinical pathways for common conditions, a pathway...... for pneumonia was designed and implemented in 2010. Problem In spite of our clinical pathway for CAP we found delays in start of treatment, overuse of antibiotics and long length of stay (LOS). Mortality was nearly 20 %. Assessment of problem and analysis of its causes We established an audit group of two...... nurses and two senior doctors. Direct observations of the clinical processes revealed problems of coordination, complex disease trajectories that did not fit with the pneumonia pathway, unclear guidelines and variation in their interpretation. Intervention We designed a measurement system to monitor...

  7. Observation of Central Toroidal Rotation Induced by ICRF on EAST

    Science.gov (United States)

    Pan, Xiayun; Wang, Fudi; Zhang, Xinjun; Lyu, Bo; Chen, Jun; Li, Yingying; Fu, Jia; Shi, Yuejiang; Yu, Yi; Ye, Minyou; Wan, Baonian

    2016-02-01

    Core plasma rotation of both L-mode and H-mode discharges with ion cyclotron range of frequency (ICRF) minority heating (MH) scheme was measured with a tangential X-ray imaging crystal spectrometer on EAST (Experimental Advanced Superconducting Tokamak). Co-current central impurity toroidal rotation change was observed in ICRF-heated L- and H-mode plasmas. Rotation increment as high as 30 km/s was generated at ∼1.7 MW ICRF power. Scaling results showed similar trend as the Rice scaling but with significant scattering, especially in L-mode plasmas. We varied the plasma current, toroidal field and magnetic configuration individually to study their effect on L-mode plasma rotation, while keeping the other major plasma parameters and heating unchanged during the scanning. It was found that larger plasma current could induce plasma rotation more efficiently. A scan of the toroidal magnetic field indicated that the largest rotation was obtained for on-axis ICRF heating. A comparison between lower-single-null (LSN) and double-null (DN) configurations showed that LSN discharges rendered a larger rotation change for the same power input and plasma parameters. supported by the National Magnetic Confinement Fusion Science Program of China (Nos. 2013GB112004 and 2015GB103002), National Natural Science Foundation of China (Nos. 11175208, 11305212, 11375235, 11405212 and 11261140328), the Innovative Program of Development Foundation of Hefei Center for Physical Science and Technology (2014FXCX003) and Brain Korea 21 Program for Leading Universities & Students (BK21 PLUS)

  8. D{sup -} energy spectrum in toroidal quantum ring

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, C A; Gutierrez, W; Garcia, L F [Universidad Industrial de Santander, Bucaramanga (Colombia); Marin, J H, E-mail: jhmarin@unal.edu.c [Universidad Nacional-Colombia, Medellin-Colombia, AA3840 (Colombia)

    2009-05-01

    The structure of energy spectrum of the negative donor centre in a toroidal-shaped quantum ring with two different morphologies of the cross-section is analyzed. By using the adiabatic procedure we have deduced a one-dimensional wave equation with periodic conditions which describes the low-lying energy levels related to the electrons rotation around the symmetry axis. Our results are in good agreement with those previously obtained as the size of the ring cross-section tends to zero.

  9. Experimental observation of crystalline particle flows in toroidal dust clouds

    Energy Technology Data Exchange (ETDEWEB)

    Wilms, Jochen, E-mail: wilms@physik.uni-kiel.de; Piel, Alexander [IEAP, Christian-Albrechts-Universität, D-24098 Kiel (Germany); Reichstein, Torben [IEAP, Christian-Albrechts-Universität, D-24098 Kiel (Germany); DME, Kiel University of Applied Sciences, Grenzstr. 3, D-24147 Kiel (Germany)

    2015-06-15

    The dust flow in a toroidal dust trap is studied experimentally. The flow is driven by the Hall component of the ion drag force in a magnetized plasma. Dust density waves are found in a torus with a large minor radius a, which allows for several wavelength, 2a>5λ, in the (mostly) radial direction of the ion flow. Beyond an intermediate state with radial sloshing oscillations, a crystalline dust flow with suppressed wave activity could be realized for 2a<2λ. The particles arrange themselves in distinct layers with hexagonal-like local order. Smooth transitions between states with different numbers of layers are found in the inhomogeneous flow.

  10. Simulation of dust streaming in toroidal traps: Stationary flows

    Energy Technology Data Exchange (ETDEWEB)

    Reichstein, Torben; Piel, Alexander [IEAP, Christian-Albrechts-Universitaet, D-24098 Kiel (Germany)

    2011-08-15

    Molecular-dynamic simulations were performed to study dust motion in a toroidal trap under the influence of the ion drag force driven by a Hall motion of the ions in E x B direction, gravity, inter-particle forces, and friction with the neutral gas. This article is focused on the inhomogeneous stationary streaming motion. Depending on the strength of friction, the spontaneous formation of a stationary shock or a spatial bifurcation into a fast flow and a slow vortex flow is observed. In the quiescent streaming region, the particle flow features a shell structure which undergoes a structural phase transition along the flow direction.

  11. Stationary motion of a self gravitating toroidal incompressible liquid layer

    CERN Document Server

    Fusco, Giorgio; Oliva, Waldyr M

    2012-01-01

    We consider an incompressible fluid contained in a toroidal stratum which is only subjected to Newtonian self-attraction. Under the assumption of infinitesimal tickness of the stratum we show the existence of stationary motions during which the stratum is approximatly a round torus (with radii r, R and R>>r) that rotates around its axis and at the same time rolls on itself. Therefore each particle of the stratum describes an helix-like trajectory around the circumference of radius R that connects the centers of the cross sections of the torus.

  12. Total and paired domination numbers of toroidal meshes

    CERN Document Server

    Hu, Fu-Tao

    2011-01-01

    Let $G$ be a graph without isolated vertices. The total domination number of $G$ is the minimum number of vertices that can dominate all vertices in $G$, and the paired domination number of $G$ is the minimum number of vertices in a dominating set whose induced subgraph contains a perfect matching. This paper determines the total domination number and the paired domination number of the toroidal meshes, i.e., the Cartesian product of two cycles $C_n$ and $C_m$ for any $n\\ge 3$ and $m\\in\\{3,4\\}$, and gives some upper bounds for $n, m\\ge 5$.

  13. Fabrication of toroidal composite pressure vessels. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Dodge, W.G.; Escalona, A.

    1996-11-24

    A method for fabricating composite pressure vessels having toroidal geometry was evaluated. Eight units were fabricated using fibrous graphite material wrapped over a thin-walled aluminum liner. The material was wrapped using a machine designed for wrapping, the graphite material was impregnated with an epoxy resin that was subsequently thermally cured. The units were fabricated using various winding patterns. They were hydrostatically tested to determine their performance. The method of fabrication was demonstrated. However, the improvement in performance to weight ratio over that obtainable by an all metal vessel probably does not justify the extra cost of fabrication.

  14. Position indicating split toroid for the RACE experiment

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, B. [Nuclear Engineering Teaching Laboratory, University of Texas, 10100 Burnet Road, Austin, TX 78758 (United States)]. E-mail: bhurst@mail.utexas.edu; Folkman, K. [Idaho Accelerator Center, Idaho State University, Pocatello, ID 83201 (United States)

    2007-08-15

    Aspects of the recent reactor accelerator coupled experiments (RACE) carried out at University of Texas Nuclear Engineering Teaching Laboratory will be discussed. In particular, a compact instrument that allowed a continuous non-invasive means of determining the relative electron beam position was developed. The operation of the instrument is similar to an inductive current pick up toroid except that the core is sectioned radially, which allows spatial information to be derived from the induced voltages. Results of initial tests, both in beam and with a pulser, will be presented along with plans to optimize future designs.

  15. Toroidal equilibrium with low frequency wave driven currents

    Energy Technology Data Exchange (ETDEWEB)

    Ehst, D.A.

    1984-12-01

    In the absence of an emf the parallel current, j/sub parallel/, in a steady state tokamak will consist of a neoclassical portion plus a wave-driven contribution. Using the drift kinetic equation, the quasilinear (wave-driven) current is computed for high phase speed waves in a torus, and this is combined with the neoclassical term to obtain the general expression for the flux surface average . For a given pressure profile this technique fully determines the MHD equilibrium, permitting the study of a new class of toroidal equilibria.

  16. Resistive demountable toroidal-field coils for tokamak reactors

    Energy Technology Data Exchange (ETDEWEB)

    Jassby, D.L.; Jacobsen, R.A.; Kalnavarns, J.; Masson, L.S.; Sekot, J.P.

    1981-07-01

    Readily demountable TF (toroidal-field) coils allow complete access to the internal components of a tokamak reactor for maintenance of replacement. The requirement of readily demountable joints dictates the use of water-cooled resistive coils, which have a host of decisive advantages over superconducting coils. Previous papers have shown that resistive TF coils for tokamak reactors can operate in the steady state with acceptable power dissipation (typically, 175 to 300 MW). This paper summarizes results of parametric studies of size optimization of rectangular TF coils and of a finite-element stress analysis, and examines several candidate methods of implementing demountable joints for rectangular coils constructed of plate segments.

  17. Decommissioning of offshore installations

    Energy Technology Data Exchange (ETDEWEB)

    Oeen, Sigrun; Iversen, Per Erik; Stokke, Reidunn; Nielsen, Frantz; Henriksen, Thor; Natvig, Henning; Dretvik, Oeystein; Martinsen, Finn; Bakke, Gunnstein

    2010-07-01

    New legislation on the handling and storage of radioactive substances came into force 1 January 2011. This version of the report is updated to reflect this new regulation and will therefore in some chapters differ from the Norwegian version (see NEI-NO--1660). The Ministry of the Environment commissioned the Climate and Pollution Agency to examine the environmental impacts associated with the decommissioning of offshore installations (demolition and recycling). This has involved an assessment of the volumes and types of waste material and of decommissioning capacity in Norway now and in the future. This report also presents proposals for measures and instruments to address environmental and other concerns that arise in connection with the decommissioning of offshore installations. At present, Norway has four decommissioning facilities for offshore installations, three of which are currently involved in decommissioning projects. Waste treatment plants of this kind are required to hold permits under the Pollution Control Act. The permit system allows the pollution control authority to tailor the requirements in a specific permit by evaluating conditions and limits for releases of pollutants on a case-to-case basis, and the Act also provides for requirements to be tightened up in line with the development of best available techniques (BAT). The environmental risks posed by decommissioning facilities are much the same as those from process industries and other waste treatment plants that are regulated by means of individual permits. Strict requirements are intended to ensure that environmental and health concerns are taken into account. The review of the four Norwegian decommissioning facilities in connection with this report shows that the degree to which requirements need to be tightened up varies from one facility to another. The permit for the Vats yard is newest and contains the strictest conditions. The Climate and Pollution Agency recommends a number of measures

  18. Toroidal modelling of RMP response in ASDEX Upgrade: coil phase scan, q 95 dependence, and toroidal torques

    Science.gov (United States)

    Liu, Yueqiang; Ryan, D.; Kirk, A.; Li, Li; Suttrop, W.; Dunne, M.; Fischer, R.; Fuchs, J. C.; Kurzan, B.; Piovesan, P.; Willensdorfer, M.; the ASDEX Upgrade Team; the EUROfusion MST1 Team

    2016-05-01

    The plasma response to the vacuum resonant magnetic perturbation (RMP) fields, produced by the ELM control coils in ASDEX Upgrade experiments, is computationally modelled using the MARS-F/K codes (Liu et al 2000 Phys. Plasmas 7 3681, Liu et al 2008 Phys. Plasmas 15 112503). A systematic investigation is carried out, considering various plasma and coil configurations as in the ELM control experiments. The low q plasmas, with {{q}95}˜ 3.8 (q 95 is the safety factor q value at 95% of the equilibrium poloidal flux), responding to low n (n is the toroidal mode number) field perturbations from each single row of the ELM coils, generates a core kink amplification effect. Combining two rows, with different toroidal phasing, thus leads to either cancellation or reinforcement of the core kink response, which in turn determines the poloidal location of the peak plasma surface displacement. The core kink response is typically weak for the n  =  4 coil configuration at low q, and for the n  =  2 configuration but only at high q ({{q}95}˜ 5.5 ). A phase shift of around 60 degrees for low q plasmas, and around 90 degrees for high q plasmas, is found in the coil phasing, between the plasma response field and the vacuum RMP field, that maximizes the edge resonant field component. This leads to an optimal coil phasing of about 100 (-100) degrees for low (high) q plasmas, that maximizes both the edge resonant field component and the plasma surface displacement near the X-point of the separatrix. This optimal phasing closely corresponds to the best ELM mitigation observed in experiments. A strong parallel sound wave damping moderately reduces the core kink response but has minor effect on the edge peeling response. For low q plasmas, modelling shows that both the resonant electromagnetic torque and the neoclassical toroidal viscous (NTV) torque (due to the presence of 3D magnetic field perturbations) contribute to the toroidal flow damping, in particular near the

  19. From Blogs to Bottle Caps

    Science.gov (United States)

    Edinger, Ted

    2012-01-01

    There is a wonderful community of art educators connecting a once-isolated profession through blogging. Art educators around the world are sharing ideas and communicating with their peers through this amazing resource. In this article, the author describes the bottle cap mural at Tulip Grove Elementary School which was inspired by this exchange of…

  20. Inversion of the Abel equation for toroidal density distributions

    CERN Document Server

    Ciotti, L

    1999-01-01

    In this paper I present three new results of astronomical interest concerning the theory of Abel inversion. 1) I show that in the case of a spatial emissivity that is constant on toroidal surfaces and projected along the symmetry axis perpendicular to the torus' equatorial plane, it is possible to invert the projection integral. From the surface (i.e. projected) brightness profile one then formally recovers the original spatial distribution as a function of the toroidal radius. 2) By applying the above-described inversion formula, I show that if the projected profile is described by a truncated off-center gaussian, the functional form of the related spatial emissivity is very simple and - most important - nowhere negative for any value of the gaussian parameters, a property which is not guaranteed - in general - by Abel inversion. 3) Finally, I show how a generic multimodal centrally symmetric brightness distribution can be deprojected using a sum of truncated off-center gaussians, recovering the spatial emis...

  1. Baryonic torii: Toroidal baryons in a generalized Skyrme model

    Science.gov (United States)

    Gudnason, Sven Bjarke; Nitta, Muneto

    2015-02-01

    We study a Skyrme-type model with a potential term motivated by Bose-Einstein condensates (BECs), which we call the BEC Skyrme model. We consider two flavors of the model: the first is the Skyrme model, and the second has a sixth-order derivative term instead of the Skyrme term, both with the added BEC-motivated potential. The model contains toroidally shaped Skyrmions, and they are characterized by two integers P and Q , representing the winding numbers of two complex scalar fields along the toroidal and poloidal cycles of the torus, respectively. The baryon number is B =P Q . We find stable Skyrmion solutions for P =1 ,2 ,3 ,4 ,5 with Q =1 , while for P =6 and Q =1 , it is only metastable. We further find that configurations with higher Q >1 are all unstable and split into Q configurations with Q =1 . Finally we discover a phase transition, possibly of first order, in the mass parameter of the potential under study.

  2. Cryogenic Characteristics of the ATLAS Barrel Toroid Superconducting Magnet

    CERN Document Server

    Pengo, R; Delruelle, N; Pezzetti, M; Pirotte, O; Passardi, Giorgio; Dudarev, A; ten Kate, H

    2008-01-01

    ATLAS, one of the experiments of the LHC accelerator under commissioning at CERN, is equipped with a large superconducting magnet the Barrel Toroid (BT) that has been tested at nominal current (20500 A). The BT is composed of eight race-track superconducting coils (each one weights about 45 tons) forming the biggest air core toroidal magnet ever built. By means of a large throughput centrifugal pump, a forced flow (about 10 liter/second at 4.5 K) provides the indirect cooling of the coils in parallel. The paper describes the results of the measurements carried out on the complete cryogenic system assembled in the ATLAS cavern situated 100 m below the ground level. The measurements include, among other ones, the static heat loads, i.e., with no or constant current in the magnet, and the dynamic ones, since additional heat losses are produced, during the current ramp-up or slow dump, by eddy currents induced on the coil casing.

  3. Instability of toroidal magnetic field in jets and plerions

    CERN Document Server

    Begelman, M C

    1997-01-01

    Jets and pulsar-fed supernova remnants (plerions) tend to develop highly organized toroidal magnetic field. Such a field structure could explain the polarization properties of some jets, and contribute to their lateral confinement. A toroidal field geometry is also central to models for the Crab Nebula - the archetypal plerion - and leads to the deduction that the Crab pulsar's wind must have a weak magnetic field. Yet this `Z-pinch' field configuration is well known to be locally unstable, even when the magnetic field is weak and/or boundary conditions slow or suppress global modes. Thus, the magnetic field structures imputed to the interiors of jets and plerions are unlikely to persist. To demonstrate this, I present a local analysis of Z-pinch instabilities for relativistic fluids in the ideal MHD limit. Kink instabilities dominate, destroying the concentric field structure and probably driving the system toward a more chaotic state in which the mean field strength is independent of radius (and in which re...

  4. Calculation of modification to the toroidal magnetic field of the Tokamak Novillo. Part II; Calculo de modificacion al campo magnetico toroidal del Tokamak nivillo. Parte II

    Energy Technology Data Exchange (ETDEWEB)

    Melendez L, L.; Chavez A, E.; Colunga S, S.; Valencia A, R.; Lopez C, R.; Gaytan G, E

    1992-03-15

    In a cylindrical magnetic topology. the confined plasma experiences 'classic' collisional transport phenomena. When bending the cylinder with the purpose of forming a toro, the magnetic field that before was uniform now it has a radial gradient which produces an unbalance in the magnetic pressure that is exercised on the plasma in the transverse section of the toro. This gives place to transport phenomena call 'neo-classicist'. In this work the structure of the toroidal magnetic field produced by toroidal coils of triangular form, to which are added even of coils of compensation with form of half moon is analyzed. With this type of coils it is looked for to minimize the radial gradient of the toroidal magnetic field. The values and characteristics of B (magnetic field) in perpendicular planes to the toro in different angular positions in the toroidal direction, looking for to cover all the cases of importance are exhibited. (Author)

  5. Investigation of toroidal acceleration and potential acceleration forces in EAST and J-TEXT plasmas

    CERN Document Server

    Wang, Fudi; Pan, Xiayun; Cheng, Zhifeng; Chen, Jun; Cao, Guangming; Wang, Yuming; Han, Xiang; Li, Hao; Wu, Bin; Chen, Zhongyong; Bitter, Manfred; Hill, Kenneth; Rice, John; Morita, Shigeru; Li, Yadong; Zhuang, Ge; Ye, Minyou; Wan, Baonian; Shi, Yuejiang

    2014-01-01

    In order to produce intrinsic rotation, bulk plasmas must be collectively accelerated by the net force exerted on them, which results from both driving and damping forces. So, to study the possible mechanisms of intrinsic rotation generation, it is only needed to understand characteristics of driving and damping terms because the toroidal driving and damping forces induce net acceleration which generates intrinsic rotation. Experiments were performed on EAST and J-TEXT for ohmic plasmas with net counter- and co-current toroidal acceleration generated by density ramping up and ramping down. Additionally on EAST, net co-current toroidal acceleration was also formed by LHCD or ICRF. For the current experimental results, toroidal acceleration was between - 50 km/s^2 in counter-current direction and 70 km/s^2 in co-current direction. According to toroidal momentum equation, toroidal electric field (E\\-(\\g(f))), electron-ion toroidal friction, and toroidal viscous force etc. may play roles in the evolution of toroi...

  6. Geodesic Acoustic Mode in Toroidally Axisymmetric Plasmas with Non-Circular Cross Sections

    Institute of Scientific and Technical Information of China (English)

    SHI Bing-Ren; LI Ji-Quan; DONG Jia-Qi

    2005-01-01

    @@ The geodesic acoustic mode in general toroidally axisymmetric plasmas such as Tokamak and spherical torus is studied in detail. The mode structure is found and the dispersion equation is derived and solved for arbitrary toroidally axi-symmetric plasmas. Besides the finite aspect ratio, effects of elongation and triangularity on this mode are clarified.

  7. The Experiment of Modulated Toroidal Current on HT-7 and HT-6M Tokamak

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The Experiments of Modulated Toroidal Current were done on the HT-6M tokamakand HT-7 superconducting tokamak. The toroidal current was modulated by programming theOhmic heating field. Modulation of the plasma current has been used successfully to suppressMHD activity in discharges near the density limit where large MHD m = 2 tearing modes weresuppressed by sufficiently large plasma current oscillations. The improved Ohmic confinementphase was observed during modulating toroidal current (MTC) on the Hefei Tokamak-6M (HT-6M) and Hefei superconducting Tokamak-7 (HT-7). A toroidal frequency-modulated current,induced by a modulated loop voltage, was added on the plasma equilibrium current. The ratio ofA.C. amplitude of plasma current to the main plasma current △Ip/Ip is about 12% ~ 30%. Thedifferent formats of the frequency-modulated toroidal current were compared.

  8. Modulating toroidal flow stabilization of edge localized modes with plasma density

    CERN Document Server

    Cheng, Shikui; Banerjee, Debabrata

    2016-01-01

    Recent EAST experiments have demonstrated mitigation and suppression of edge localized modes (ELMs) with toroidal rotation flow in higher collisionality regime, suggesting potential roles of plasma density. In this work, the effects of plasma density on the toroidal flow stabilization of the high-$n$ edge localized modes have been extensively studied in linear calculations for a circular-shaped limiter H-mode tokamak, using the extended MHD code NIMROD. In the single MHD model, toroidal flow has a weak stabilizing effects on the high-$n$ modes. Such a stabilization, however, can be significantly enhanced with the increase in plasma density. Furthermore, our calculations show that the enhanced stabilization of high-$n$ modes from toroidal flow with higher edge plasma density persists in the 2-fluid MHD model. These findings may explain the ELM mitigation and suppression by toroidal rotation in higher collisionality regime due to the enhancement of plasma density obtained in recent EAST experiments.

  9. Toroidally Asymmetric Distributions of Hydrocarbon (CD) Emission and Chemical Sputtering Sources in DIII-D

    Energy Technology Data Exchange (ETDEWEB)

    Groth, M; Brooks, N H; Fenstermacher, M E; Lasnier, C J; McLean, A G; Watkins, J G

    2006-05-16

    Measurements in DIII-D show that the carbon chemical sputtering sources along the inner divertor and center post are toroidally periodic and highest at the upstream tile edge. Imaging with a tangentially viewing camera and visible spectroscopy were used to monitor the emission from molecular hydrocarbons (CH/CD) at 430.8 nm and deuterium neutrals in attached and partially detached divertors of low-confinement mode plasmas. In contrast to the toroidally periodic CD distribution, emission from deuterium neutrals was observed to be toroidally symmetric along the inner strike zone. The toroidal distribution of the measured tile surface temperature in the inner divertor correlates with that of the CD emission, suggesting larger parallel particle and heat fluxes to the upstream tile edge, either due to toroidal tile gaps or height steps between adjacent tiles.

  10. Toroidal high-spin isomers in light nuclei with N not equal to Z

    CERN Document Server

    Staszczak, Andrzej

    2014-01-01

    The combined considerations of both the bulk liquid-drop-type behavior and the quantized aligned rotation with cranked Skyrme-Hartree-Fock approach revealed previously that even-even, N=Z, toroidal high-spin isomeric states have general occurrences for light nuclei with A between 28 and 52. We find that in this mass region there are in addition N not equal to Z toroidal high-spin isomers when the single-particle shells for neutrons and protons occur at the same cranked frequency $\\hbar \\omega$. Examples of N not equal to Z toroidal high-spin isomers, $^{36}_{16}$S$_{20}$($I$=74$\\hbar$) and $^{40}_{18}$Ar$_{22}$($I$=80,102$\\hbar$), are located and examined. The systematic properties of these N not equal to Z toroidal high-spin isomers fall into the same regular (muti-particle)-(muti-hole) patterns as other N=Z toroidal high-spin isomers.

  11. Mineral mining installation

    Energy Technology Data Exchange (ETDEWEB)

    Weirich, W.

    1984-01-24

    A longwall mineral mining installation has a conveyor and a plurality of roof support units positioned side-by-side on the goaf side of the conveyor. Each roof support unit has a roof shield having an advanceable shield extension. Each unit has a first hydraulic ram for extending its shield extension, and a second hydraulic ram for advancing the conveyor. The extension of each first ram is controlled in dependence upon the retraction of one of the second rams (either the second ram of the same unit or that of an adjacent unit). This control is effected by controlling the supply of pressurized hydraulic fluid to the first rams. In one embodiment this is carried out by a control valve which has a springloaded plunger which engages with a series of equispaced cams on the movable cylinder of the associated second ram. In another embodiment, the piston rods of the rams are provided with series of equispaced magnets. The cylinders of the rams are provided with sensors, which sense the magnets and generate control signals. A control box is provided to direct the control signals to control valves associated with the rams, so that the first rams are extended by the same distance as that through which the second rams are retracted.

  12. Mineral mining installation

    Energy Technology Data Exchange (ETDEWEB)

    Becker, K.; Rosenberg, H.; Weirich, W.

    1981-12-29

    A longwall mineral mining installation has a conveyor and a plurality of roof support units positioned side-by-side on the goaf side of the conveyor. Each roof support unit has a roof shield having an advanceable shield extension. Each unit has a first hydraulic ram for extending its shield extension, and a second hydraulic ram for advancing the conveyor. The extension of each first ram is controlled in dependence upon the retraction of one of the second rams (Either the second ram of the same unit or that of an adjacent unit). This control is effected by controlling the supply of pressurized hydraulic fluid to the first rams. In one embodiment this is carried out by a control valve which has a spring-loaded plunger which engages with a series of equispaced cams on the movable cylinder of the associated second ram. In another embodiment, the piston rods of the rams are provided with series of equispaced magnets. The cylinders of the rams are provided with sensors, which sense the magnets and generate control signals. A control box is provided to direct the control signals to control valves associated with the rams, so that the first rams are extended by the same distance as that through which the second rams are retracted.

  13. ROS Installation and Commissioning

    CERN Multimedia

    Gorini, B

    The ATLAS Readout group (a sub-group of TDAQ) has now completed the installation and commissioning of all of the Readout System (ROS) units. Event data from ATLAS is initially handled by detector specific hardware and software, but following a Level 1 Accept the data passes from the detector specific Readout Drivers (RODs) to the ROS, the first stage of the central ATLAS DAQ. Within the final ATLAS TDAQ system the ROS stores the data and on request makes it available to the Level 2 Trigger (L2) processors and to the Event Builder (EB) as required. The ROS is implemented as a large number of PCs housing custom built cards (ROBINs) and running custom multi-threaded software. Each ROBIN card (shown below) contains buffer memories to store the data, plus a field programmable gate array ( FPGA ) and an embedded PowerPC processor for management of the memories and data requests, and is implemented as a 64-bit 66 MHz PCI card. Both the software and the ROBIN cards have been designed and developed by the Readout g...

  14. Analyses of hydraulic performance of velocity caps

    DEFF Research Database (Denmark)

    Christensen, Erik Damgaard; Degn Eskesen, Mark Chr.; Buhrkall, Jeppe;

    2014-01-01

    The hydraulic performance of a velocity cap has been investigated. Velocity caps are often used in connection with offshore intakes. CFD (computational fluid dynamics) examined the flow through the cap openings and further down into the intake pipes. This was combined with dimension analyses...

  15. Motion of polar cap arcs

    Science.gov (United States)

    Hosokawa, K.; Moen, J. I.; Shiokawa, K.; Otsuka, Y.

    2011-01-01

    A statistics of motion of polar cap arcs is conducted by using 5 years of optical data from an all-sky imager at Resolute Bay, Canada (74.73°N, 265.07°E). We identified 743 arcs by using an automated arc detection algorithm and statistically examined their moving velocities as estimated by the method of Hosokawa et al. (2006). The number of the arcs studied is about 5 times larger than that in the previous statistics of polar cap arcs by Valladares et al. (1994); thus, we could expect to obtain more statistically significant results. Polar cap arcs are found to fall into two distinct categories: the By-dependent and By-independent arcs. The motion of the former arcs follows the rule reported by Valladares et al. (1994), who showed that stable polar cap arcs move in the direction of the interplanetary magnetic field (IMF) By. About two thirds of the arcs during northward IMF conditions belong to this category. The latter arcs always move poleward irrespective of the sign of the IMF By, which possibly correspond to the poleward moving arcs in the morning side reported by Shiokawa et al. (1997). At least one third of the arcs belong to this category. The By-dependent arcs tend to move faster when the magnitude of the IMF By is larger, suggesting that the transport of open flux by lobe reconnection from one polar cap compartment to the other controls their motion. In contrast, the speed of the By-independent arcs does not correlate with the magnitude of the By. The motions of both the By-dependent and By-independent arcs are most probably caused by the magnetospheric convection. Convection in the region of By-dependent arcs is affected by the IMF By, which indicates that their sources may be on open field lines or in the closed magnetosphere adjacent to the open-closed boundary, whereas By-independent arcs seem to be well on closed field lines. Hence, the magnetospheric source of the two types of arc may be different. This implies that the mechanisms causing the

  16. 3D toroidal physics: testing the boundaries of symmetry breaking

    Science.gov (United States)

    Spong, Don

    2014-10-01

    Toroidal symmetry is an important concept for plasma confinement; it allows the existence of nested flux surface MHD equilibria and conserved invariants for particle motion. However, perfect symmetry is unachievable in realistic toroidal plasma devices. For example, tokamaks have toroidal ripple due to discrete field coils, optimized stellarators do not achieve exact quasi-symmetry, the plasma itself continually seeks lower energy states through helical 3D deformations, and reactors will likely have non-uniform distributions of ferritic steel near the plasma. Also, some level of designed-in 3D magnetic field structure is now anticipated for most concepts in order to lead to a stable, steady-state fusion reactor. Such planned 3D field structures can take many forms, ranging from tokamaks with weak 3D ELM-suppression fields to stellarators with more dominant 3D field structures. There is considerable interest in the development of unified physics models for the full range of 3D effects. Ultimately, the questions of how much symmetry breaking can be tolerated and how to optimize its design must be addressed for all fusion concepts. Fortunately, significant progress is underway in theory, computation and plasma diagnostics on many issues such as magnetic surface quality, plasma screening vs. amplification of 3D perturbations, 3D transport, influence on edge pedestal structures, MHD stability effects, modification of fast ion-driven instabilities, prediction of energetic particle heat loads on plasma-facing materials, effects of 3D fields on turbulence, and magnetic coil design. A closely coupled program of simulation, experimental validation, and design optimization is required to determine what forms and amplitudes of 3D shaping and symmetry breaking will be compatible with future fusion reactors. The development of models to address 3D physics and progress in these areas will be described. This work is supported both by the US Department of Energy under Contract DE

  17. Completion of the first TRT End-cap

    CERN Multimedia

    Catinaccio, A; Rohne, O

    On July 1, the first end-cap of the ATLAS Transition Radiation Tracker (TRT) was successfully completed in terms of the integration of the wheels assembled in Russia with their front-end electronics. The two groups of the detector, fully assembled and equipped with front-end electronics, were rotated from their horizontal position during stacking to their nominal vertical position, in which they will be integrated with the corresponding end-cap silicon-strip (SCT) detector towards the end of 2005, before installation into ATLAS in spring 2006. After starting the assembly in the SR building one year ago, the TRT team reached this important milestone, which marks the final realization and validation of the engineering concept developed by the CERN DT1 (ex-TA1) and ATT teams. A TRT end-cap consists of two sets of identical and independent wheels. The first type of wheels (type A, 12 wheels, positioned closest to the primary interaction point) contains 6144 radial straws positioned in eight successive layers s...

  18. Proceedings of the third symposium on the physics and technology of compact toroids in the magnetic fusion energy program

    Energy Technology Data Exchange (ETDEWEB)

    Siemon, R.E. (comp.)

    1981-03-01

    This document contains papers contributed by the participants of the Third Symposium on Physics and Technology of Compact Toroids in the Magnetic Fusion Energy Program. Subjects include reactor aspects of compact toroids, energetic particle rings, spheromak configurations (a mixture of toroidal and poloidal fields), and field-reversed configurations (FRC's that contain purely poloidal field).

  19. Toroidal bubbles with circulation in ideal hydrodynamics: A variational approach

    DEFF Research Database (Denmark)

    Ruban, V.P.; Juul Rasmussen, J.

    2003-01-01

    Incompressible, inviscid, irrotational, unsteady flows with circulation Gamma around a distorted toroidal bubble are considered. A general variational principle that determines the evolution of the bubble shape is formulated. For a two-dimensional (2D) cavity with a constant area A, exact...... pseudodifferential equations of motion are derived, based on variables that determine a conformal mapping of the unit circle exterior into the region occupied by the fluid. A closed expression for the Hamiltonian of the 2D system in terms of canonical variables is obtained. Stability of a stationary drifting 2D...... hollow vortex is demonstrated, when the gravity is small, gA(3/2)/Gamma(2)flows a simplified Lagrangian is suggested, inasmuch as the bubble shape is well described by the center line R(xi,t) and by an approximately circular cross section...

  20. Analysis of recurrent patterns in toroidal magnetic fields.

    Science.gov (United States)

    Sanderson, Allen R; Chen, Guoning; Tricoche, Xavier; Pugmire, David; Kruger, Scott; Breslau, Joshua

    2010-01-01

    In the development of magnetic confinement fusion which will potentially be a future source for low cost power, physicists must be able to analyze the magnetic field that confines the burning plasma. While the magnetic field can be described as a vector field, traditional techniques for analyzing the field's topology cannot be used because of its Hamiltonian nature. In this paper we describe a technique developed as a collaboration between physicists and computer scientists that determines the topology of a toroidal magnetic field using fieldlines with near minimal lengths. More specifically, we analyze the Poincaré map of the sampled fieldlines in a Poincaré section including identifying critical points and other topological features of interest to physicists. The technique has been deployed into an interactive parallel visualization tool which physicists are using to gain new insight into simulations of magnetically confined burning plasmas.

  1. On the interaction of turbulence and flows in toroidal plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Stroth, U; Manz, P; Ramisch, M [Institut fuer Plasmaforschung, Universitaet Stuttgart, 70569 Stuttgart (Germany)

    2011-02-15

    In toroidally confined plasmas, background E x B flows, microturbulence and zonal flows constitute a tightly coupled dynamic system and the description of confinement transitions needs a self-consistent treatment of these players. The background radial electric field, linked to neoclassical ambipolar transport, has an impact on the interaction between zonal flows and turbulence by tilting and anisotropization of turbulent eddies. Zonal-flow drive is shown to be non-local in wavenumber space and is described as a straining-out process instead as a local inverse cascade. The straining-out process is also discussed as an option to explain turbulence suppression in sheared flows and could be the cause of predator-prey oscillations in the turbulence zonal-flow system.

  2. First assembly phase for the ATLAS toroid coils

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    The ATLAS barrel toroid system consists of eight coils, each of axial length 25.3 m, assembled radially and symmetrically around the beam axis. The coils are of a flat racetrack type with two double-pancake windings made of 20.5 kA aluminium-stabilized niobium-titanium superconductor. In the first phase of assembly, the two 'pancakes' are packed into their vacuum vessel. This is done using bladders filled with resin and glass microbeads under pressure. The resin is heated and, once cooled, holds the pancakes in place. The operation has to be performed on both sides of the coil, which necessitated a special technique to turn the coils over and then transport them to the heating table. Photos 01, 02, 03: Transporting the coil to the heating table using a special lifting gantry manufactured at JINR-Dubna, Russia in preparation for the 'bladderisation' operation.

  3. Toroid Joining Gun. [thermoplastic welding system using induction heating

    Science.gov (United States)

    Buckley, J. D.; Fox, R. L.; Swaim, R J.

    1985-01-01

    The Toroid Joining Gun is a low cost, self-contained, portable low powered (100-400 watts) thermoplastic welding system developed at Langley Research Center for joining plastic and composite parts using an induction heating technique. The device developed for use in the fabrication of large space sructures (LSST Program) can be used in any atmosphere or in a vacuum. Components can be joined in situ, whether on earth or on a space platform. The expanded application of this welding gun is in the joining of thermoplastic composites, thermosetting composites, metals, and combinations of these materials. Its low-power requirements, light weight, rapid response, low cost, portability, and effective joining make it a candidate for solving many varied and unique bonding tasks.

  4. Gasdynamic characteristics of toroidal shock and detonation wave converging

    Institute of Scientific and Technical Information of China (English)

    TENG; Honghui; JIANG; Zonglin

    2005-01-01

    The modified CCW relation is applied to analyzing the shock, detonation wave converging and the role of chemical reactions in the process. Results indicate that the shock wave is strengthened faster than the detonation wave in the converging at the same initial Mach number. Euler equations implemented with a detailed chemical reaction model are solved to simulate toroidal shock and detonation wave converging. Gasdynamic characteristics of the converging are investigated, including wave interaction patterns, observable discrepancies and physical phenomena behind them. By comparing wave diffractions, converging processes and pressure evolutions in the focusing area, the different effects of chemical reactions on diffracting and converging processes are discussed and the analytic conclusion is demonstrated through the observation of numerical simulations.

  5. Differentially rotating magnetised neutron stars: production of toroidal magnetic fields

    CERN Document Server

    Thampan, A V

    2004-01-01

    We initiate numerical studies of differentially rotating magnetised (proto) neutron stars by studying - through construction from first principles - the coupling between an assumed differential rotation and an impressed magnetic field. For a perfect incompressible, homogeneous, non-dissipative fluid sphere immersed in an ambient plasma, we solve the (coupled) azimuthal components of the Navier-Stokes equation and the Maxwell induction equation. The assumed time--independent poloidal field lines get dragged by the rotating fluid and produce toroidal magnetic fields. Surface magnetic fields take away energy redistributing the angular momentum to produce rigid rotation along poloidal field lines. Due to absence of viscous dissipation, sustained torsional oscillations are set up within the star. However, the perpetual oscillations of neighbouring `closed' field lines get increasingly out of phase with time, leading to structure build up as in Liu & Shapiro (2004) implying the importance of taking into account...

  6. Stability of the toroidal magnetic field in stellar radiation zones

    CERN Document Server

    Bonanno, Alfio

    2011-01-01

    Understanding the stability of the magnetic field in radiation zones is of crucial importance for various processes in stellar interior like mixing, circulation and angular momentum transport. The stability properties of a star containing a prominent toroidal field in a radiation zone is investigated by means of a linear stability analysis in the Boussinesq approximation taking into account the effect of thermal conductivity. The growth rate of the instability is explicitly calculated and the effects of stable stratification and heat transport are discussed in detail. It is argued that the stabilizing influence of gravity can never entirely suppress the instability caused by electric currents in radiation zones although the stable stratification can significantly decrease the growth rate of instability

  7. Transport Bifurcation Induced by Sheared Toroidal Flow in Tokamak Plasmas

    CERN Document Server

    Highcock, E G; Parra, F I; Schekochihin, A A; Roach, C M; Cowley, S C

    2011-01-01

    First-principles numerical simulations are used to describe a transport bifurcation in a differentially rotating tokamak plasma. Such a bifurcation is more probable in a region of zero magnetic shear, where the component of the sheared toroidal flow that is perpendicular to the magnetic field has the strongest suppressing effect on the turbulence, than one of finite magnetic shear. Where the magnetic shear is zero, there are no growing linear eigenmodes at any finite value of flow shear. However, subcritical turbulence can be sustained, owing to the transient growth of modes driven by the ion temperature gradient (ITG) and the parallel velocity gradient (PVG). Nonetheless, in a parameter space containing a wide range of temperature gradients and velocity shears, there is a sizeable window where all turbulence is suppressed. Combined with the relatively low transport of momentum by collisional (neoclassical) mechanisms, this produces the conditions for a bifurcation from low to high temperature and velocity gr...

  8. Density Measurement of Compact Toroid with Mach-Zehnder Interferometer

    Science.gov (United States)

    Laufman-Wollitzer, Lauren; Endrizzi, Doug; Brookhart, Matt; Flanagan, Ken; Forest, Cary

    2016-10-01

    Utilizing a magnetized coaxial plasma gun (MCPG) built by Tri Alpha Energy, a dense compact toroid (CT) is created and injected at high speed into the Wisconsin Plasma Astrophysics Laboratory (WiPAL) vessel. A modified Mach-Zehnder interferometer from the Line-Tied Reconnection Experiment (LTRX) provides an absolute measurement of electron density. The interferometer is located such that the beam intersects the plasma across the diameter of the MCPG drift region before the CT enters the vessel. This placement ensures that the measurement is taken before the CT expand. Results presented will be used to further analyze characteristics of the CT. Funding provided by DoE, NSF, and WISE Summer Research.

  9. Global Theory to Understand Toroidal Drift Waves in Steep Gradient

    CERN Document Server

    Xie, Hua-Sheng

    2016-01-01

    Toroidal drift waves with unconventional mode structures and non-ground eigenstates, which differ from typical ballooning structure mode, are found to be important recently by large scale global gyrokinetic simulations and especially become dominant at strong gradient edge plasmas [cf., Xie and Xiao, Phys. Plasmas, 22, 090703 (2015)]. The global stability and mode structures of drift wave in this steep edge density and temperature gradients are examined by both direct numerical solutions of a model two-dimensional eigen equation and analytical theory employing WKB-ballooning approach. Theory agrees with numerical solutions quite well. Our results indicate that (i) non-ground eigenstates and unconventional mode structures generally exist and can be roughly described by two parameters `quantum number' $l$ and ballooning angle $\\vartheta_k$, (ii) local model can overestimate the growth rate largely, say, $>50\\%$, and (iii) the narrow steep equilibrium profile leads to twisting (triangle-like) radial mode structu...

  10. Heterotic free fermionic and symmetric toroidal orbifold models

    CERN Document Server

    Athanasopoulos, P; Nibbelink, S Groot; Mehta, V M

    2016-01-01

    Free fermionic models and symmetric heterotic toroidal orbifolds both constitute exact backgrounds that can be used effectively for phenomenological explorations within string theory. Even though it is widely believed that for Z2xZ2 orbifolds the two descriptions should be equivalent, a detailed dictionary between both formulations is still lacking. This paper aims to fill this gap: We give a detailed account of how the input data of both descriptions can be related to each other. In particular, we show that the generalized GSO phases of the free fermionic model correspond to generalized torsion phases used in orbifold model building. We illustrate our translation methods by providing free fermionic realizations for all Z2xZ2 orbifold geometries in six dimensions.

  11. Manufacturing aspects of the ATLAS barrel toroid double pancakes

    CERN Document Server

    Drago, G; Gagliardi, P; Laurenti, A; Marabotto, R; Penco, R

    2002-01-01

    In 1999 INFN (Istituto Nazionale di Fisica Nucleare) ordered to ANSALDO the manufacturing of 16 double pancakes for the ATLAS BARREL TOROID. In July 2001 four Double Pancakes have already been completed and shipped to the integration site. In this paper the main aspects of the manufacturing of the largest superconducting coils ever built (5*25 m) are described. The main phases of the manufacturing procedure are reviewed starting from the conductor preparation to the VPI impregnation, including references to the materials used as well as to the relevant customer's requirements. In particular the special winding form and the winding technique are treated. For each phase the most critical aspects and the relevant solutions are pointed out. Particular details about the technical solutions adopted for the impregnation and curing of the Double Pancake, which could not be performed inside an autoclave due to the huge dimension of the coil itself, are reported. Finally the methods used for the dimensional and electri...

  12. Cleaning procedure for improved photothermal background of toroidal optical microresonators

    Science.gov (United States)

    Horak, Erik H.; Knapper, Kassandra A.; Heylman, Kevin D.; Goldsmith, Randall H.

    2016-09-01

    High Q-factors and small mode volumes have made toroidal optical microresonators exquisite sensors to small shifts in the effective refractive index of the WGM modes. Eliminating contaminants and improving quality factors is key for many different sensing techniques, and is particularly important for photothermal imaging as contaminants add photothermal background obscuring objects of interest. Several different cleaning procedures including wet- and dry-chemical procedures are tested for their effect on Q-factors and photothermal background. RCA cleaning was shown to be successful in contrast to previously described acid cleaning procedures, most likely due to the different surface reactivity of the acid reagents used. UV-ozone cleaning was shown to be vastly superior to O2 plasma cleaning procedures, significantly reducing the photothermal background of the resonator.

  13. The Kirchhoff Index of Toroidal Meshes and Variant Networks

    Directory of Open Access Journals (Sweden)

    Jia-Bao Liu

    2014-01-01

    Full Text Available The resistance distance is a novel distance function on electrical network theory proposed by Klein and Randić. The Kirchhoff index Kf(G is the sum of resistance distances between all pairs of vertices in G. In this paper, we established the relationships between the toroidal meshes network Tm×n and its variant networks in terms of the Kirchhoff index via spectral graph theory. Moreover, the explicit formulae for the Kirchhoff indexes of L(Tm×n, S(Tm×n, T(Tm×n, and C(Tm×n were proposed, respectively. Finally, the asymptotic behavior of Kirchhoff indexes in those networks is obtained by utilizing the applications of analysis approach.

  14. Modeling the rapid de-swelling of toroidal hydrogels

    Science.gov (United States)

    Nikolov, Svetoslav; Chang, Ya-Wen; Alexeev, Alexander; Fernandez de Las Nieves, Alberto

    2015-03-01

    The utilization of synthetic hydrogel networks as 3-D cell culture platforms has allowed researchers to more effectively study how epigenetic factors affect cell growth and physiology. As a whole, this has emphasized the biomechanical role of scaffold structures and led to a number of advances in tissue engineering. Our current research focuses on modeling temperature activated shape transformations of toroidal poly(N-isopropylacrylamide) pNIPAM gels. We use dissipative particle dynamics (DPD) to simulate the steady (slow heating rates) and unsteady (fast heating rates) de-swelling behavior of these thermo-sensitive gels. Our simulations show that for slow heating rates the aspect ratio of the tori remains constant during de-swelling. For rapid heating rates we observe buckling instabilities. Our simulations agree with the experimental observations. Financial support by NSF CAREER Award DMR-1255288 is gratefully acknowledged.

  15. Ion temperature and toroidal rotation in JET's low torque plasmas

    Science.gov (United States)

    Bernardo, J.; Nave, M. F. F.; Giroud, C.; Reyes Cortes, S.; Bizarro, João P. S.

    2016-11-01

    This paper reports on the procedure developed as the best method to provide an accurate and reliable estimation of the ion temperature Ti and the toroidal velocity vϕ from Charge-eXchange Recombination Spectroscopy (CXRS) data from intrinsic rotation experiments at the Joint European Torus with the carbon wall. The low impurity content observed in such plasmas, resulting in low active CXRS signal, alongside low Doppler shifts makes the determination of Ti and vϕ particularly difficult. The beam modulation method will be discussed along with the measures taken to increase photon statistics and minimise errors from the absolute calibration and magneto-hydro-dynamics effects that may impact the CXRS passive emission.

  16. Effects of magnetic islands on bootstrap current in toroidal plasmas

    Science.gov (United States)

    Dong, G.; Lin, Z.

    2017-03-01

    The effects of magnetic islands on electron bootstrap current in toroidal plasmas are studied using gyrokinetic simulations. The magnetic islands cause little changes of the bootstrap current level in the banana regime because of trapped electron effects. In the plateau regime, the bootstrap current is completely suppressed at the island centers due to the destruction of trapped electron orbits by collisions and the flattening of pressure profiles by the islands. In the collisional regime, small but finite bootstrap current can exist inside the islands because of the pressure gradients created by large collisional transport across the islands. Finally, simulation results show that the bootstrap current level increases near the island separatrix due to steeper local density gradients.

  17. The angular momentum transport by unstable toroidal magnetic fields

    CERN Document Server

    Ruediger, G; Spada, F; Tereshin, I

    2014-01-01

    We demonstrate with a nonlinear MHD code that angular momentum can be transported due to the magnetic instability of toroidal fields under the influence of differential rotation, and that the resulting effective viscosity may be high enough to explain the almost rigid-body rotation observed in radiative stellar cores. The fields are assumed strong enough and the density stratification weak enough that the influence of the 'negative' buoyancy in the radiative zones can be neglected. Only permanent current-free fields and only those combinations of rotation rates and magnetic field amplitudes which provide maximal numerical values of the viscosity are considered. We find that the dimensionless ratio of the turbulent over molecular viscosity, \

  18. Benzonorbornadiene end caps for PMR resins

    Science.gov (United States)

    Panigot, Michael J.; Waters, John F.; Varde, Uday; Sutter, James K.; Sukenik, Chaim N.

    1992-01-01

    Several ortho-disubstituted benzonorbornadiene derivatives are described. These molecules contain acid, ester, or anhydride functionality permitting their use as end caps in PMR (polymerization of monomer reactants) polyimide systems. The replacement of the currently used norbornenyl end caps with benzonorbornadienyl end caps affords resins of increased aromatic content. It also allows evaluation of some mechanistic aspects of PMR cross-linking. Initial testing of N-phenylimide model compounds and of actual resin formulations using the benzonorbornadienyl end cap reveals that they undergo efficient thermal crosslinking to give oligomers with physical properties and thermal stability comparable to commercial norbornene-end-capped PMR systems.

  19. Parametric design studies of toroidal magnetic energy storage units

    Science.gov (United States)

    Herring, J. Stephen

    Superconducting magnetic energy storage (SMES) units have a number of advantages as storage devices. Electrical current is the input, output and stored medium, allowing for completely solid-state energy conversion. The magnets themselves have no moving parts. The round trip efficiency is higher than those for batteries, compressed air or pumped hydro. Output power can be very high, allowing complete discharge of the unit within a few seconds. Finally, the unit can be designed for a very large number of cycles, limited basically by fatigue in the structural components. A small systems code was written to produce and evaluate self-consistent designs for toroidal superconducting energy storage units. The units can use either low temperature or high temperature superconductors. The coils have D shape where the conductor and its stabilizer/structure is loaded only in tension and the centering forces are borne by a bucking cylinder. The coils are convectively cooled from a cryogenic reservoir in the bore of the coils. The coils are suspended in a cylindrical metal shell which protects the magnet during rail, automotive or shipboard use. It is important to note that the storage unit does not rely on its surroundings for structural support, other than normal gravity and inertial loads. Designs are presented for toroidal energy storage units produced by the systems code. A wide range of several parameters have been considered, resulting in units storing from 1 MJ to 72 GJ. Maximum fields range from 5 T to 20 T. The masses and volumes of the coils, bucking cylinder, coolant, insulation and outer shell are calculated. For unattended use, the allowable operating time using only the boiloff of the cryogenic fluid for refrigeration is calculated. For larger units, the coils were divided into modules suitable for normal truck or rail transport.

  20. Extending permanent volcano monitoring networks into Iceland's ice caps

    Science.gov (United States)

    Vogfjörd, Kristín S.; Bergsson, Bergur H.; Kjartansson, Vilhjálmur; Jónsson, Thorsteinn; Ófeigsson, Benedikt G.; Roberts, Matthew J.; Jóhannesson, Tómas; Pálsson, Finnur; Magnússon, Eyjólfur; Erlendsson, Pálmi; Ingvarsson, Thorgils; Pálssson, Sighvatur K.

    2015-04-01

    The goals of the FUTUREVOLC project are the establishment of a volcano Supersite in Iceland to enable access to volcanological data from the country's many volcanoes and the development of a multiparametric volcano monitoring and early warning system. However, the location of some of Iceland's most active volcanoes inside the country's largest ice cap, Vatnajökull, makes these goals difficult to achieve as it hinders access and proper monitoring of seismic and deformation signals from the volcanoes. To overcome these obstacles, one of the developments in the project involves experimenting with extending the permanent real-time networks into the ice cap, including installation of stations in the glacier ice. At the onset of the project, only one permanent seismic and GPS site existed within Vatnajökull, on the caldera rim of the Grímsvötn volcano. Two years into the project both seismic and GPS stations have been successfully installed and operated inside the glacier; on rock outcrops as well as on the glacier surface. The specific problems to overcome are (i) harsh weather conditions requiring sturdy and resilient equipment and site installations, (ii) darkness during winter months shutting down power generation for several weeks, (iii) high snow accumulation burying the instruments, solar panels and communication and GPS antennae, and in some locations (iv) extreme icing conditions blocking transmission signals and connection to GPS satellites, as well as excluding the possibility of power generation by wind generators. In 2013, two permanent seismic stations and one GPS station were installed on rock outcrops within the ice cap in locations with 3G connections and powered by solar panels and enough battery storage to sustain operation during the darkest winter months. These sites have successfully operated for over a year with mostly regular maintenance requirements, transmitting data in real-time to IMO for analysis. Preparations for two permanent seismic

  1. Steady state toroidal magnetic field at earth's core-mantle boundary

    Science.gov (United States)

    Levy, Eugene H.; Pearce, Steven J.

    1991-01-01

    Measurements of the dc electrical potential near the top of earth's mantle have been extrapolated into the deep mantle in order to estimate the strength of the toroidal magnetic field component at the core-mantle interface. Recent measurements have been interpreted as indicating that at the core-mantle interface, the magnetic toroidal and poloidal field components are approximately equal in magnitude. A motivation for such measurements is to obtain an estimate of the strength of the toroidal magnetic field in the core, a quantity important to our understanding of the geomagnetic field's dynamo generation. Through the use of several simple and idealized calculation, this paper discusses the theoretical relationship between the amplitude of the toroidal magnetic field at the core-mantle boundary and the actual amplitude within the core. Even with a very low inferred value of the toroidal field amplitude at the core-mantle boundary, (a few gauss), the toroidal field amplitude within the core could be consistent with a magnetohydrodynamic dynamo dominated by nonuniform rotation and having a strong toroidal magnetic field.

  2. Engineering, Manufacture and Preliminary Testing of the ITER Toroidal Field (TF) Magnet Helium Cold Circulator

    Science.gov (United States)

    Rista, P. E. C.; Shull, J.; Sargent, S.

    2015-12-01

    The ITER cryodistribution system provides the supercritical Helium (SHe) forced flow cooling to the magnet system using cold circulators. The cold circulators are located in each of five separate auxiliary cold boxes planned for use in the facility. Barber-Nichols Inc. has been awarded a contract from ITER-India for engineering, manufacture and testing of the Toroidal Field (TF) Magnet Helium Cold Circulator. The cold circulator will be extensively tested at Barber-Nichols’ facility prior to delivery for qualification testing at the Japan Atomic Energy Agency's (JAEA) test facility at Naka, Japan. The TF Cold Circulator integrates features and technical requirements which Barber-Nichols has utilized when supplying helium cold circulators worldwide over a period of 35 years. Features include a vacuum-jacketed hermetically sealed design with a very low helium leak rate, a heat shield for use with both nitrogen & helium cold sources, a broad operating range with a guaranteed isentropic efficiency over 70%, and impeller design features for high efficiency. The cold circulator will be designed to meet MTBM of 17,500 hours and MTBF of 36,000 hours. Vibration and speed monitoring are integrated into a compact package on the rotating assembly with operation and health monitoring in a multi-drop PROFIBUS communication environment using an electrical cabinet with critical features and full local and network PLC interface and control. For the testing in Japan and eventual installation in Europe, the cold circulator must be certified to the Japanese High Pressure Gas Safety Act (JHPGSA) and CE marked in compliance with the European Pressure Equipment Directive (PED) including Essential Safety Requirements (ESR). The test methodology utilized at Barber-Nichols’ facility and the resulting test data, validating the high efficiency of the TF Cold Circulator across a broad operating range, are important features of this paper.

  3. Conservation laws for collisional and turbulent transport processes in toroidal plasmas with large mean flows

    Science.gov (United States)

    Sugama, H.; Nunami, M.; Nakata, M.; Watanabe, T.-H.

    2017-02-01

    A novel gyrokinetic formulation is presented by including collisional effects into the Lagrangian variational principle to yield the governing equations for background and turbulent electromagnetic fields and gyrocenter distribution functions, which can simultaneously describe classical, neoclassical, and turbulent transport processes in toroidal plasmas with large toroidal flows on the order of the ion thermal velocity. Noether's theorem modified for collisional systems and the collision operator given in terms of Poisson brackets are applied to derivation of the particle, energy, and toroidal momentum balance equations in the conservative forms, which are desirable properties for long-time global transport simulation.

  4. Low Collisionality Neoclassical Toroidal Viscosity in Tokamaks and Quasi-symmetric Stellarators

    Science.gov (United States)

    Cole, A. J.; Hegna, C. C.; Callen, J. D.

    2008-11-01

    Non-resonant magnetic perturbations can affect plasma rotation in toroidally confined plasmas through their modification to |B|. Variations along a field line induce nonambipolar radial transport and produce a global neoclassical toroidal viscous force [NTV]. In this work, previously calculated radial particle fluxes for the low-collisionality ``ν'' and ``1/ν'' regimes [1] are unified into a single particle flux (or toroidal viscous force). Provided pitch-angle scattering dominates over collisional energy exchange, the energy component of phase space can be decoupled into independent regions (E >Ec. for ν regime, E Callen, Phys. Fluids 19, 667 (1976).

  5. Theoretical studies of possible toroidal high-spin isomers in the light-mass region

    CERN Document Server

    Staszczak, Andrzej

    2015-01-01

    We review our theoretical knowledge of possible toroidal high-spin isomers in the light mass region in 28$\\le$$A$$\\le$52 obtained previously in cranked Skyrme-Hartree-Fock calculations. We report additional toroidal high-spin isomers in $^{56}$Ni with $I$=114$\\hbar$ and 140$\\hbar$, which follow the same (multi-particle)--(multi-hole) systematics as other toroidal high-spin isomers. We examine the production of these exotic nuclei by fusion of various projectiles on $^{20}$Ne or $^{28}$Si as an active target in time-projection-chamber (TCP) experiments.

  6. Tilecal towards the Installation at Cruise Speed

    CERN Multimedia

    Miralles, Ll

    Over the last month the Tile Calorimeter has made a major step in its way towards its assembly in ATLAS. Late February the final EndCap supports were installed and the load (200 Tn) transferred from the assembly cradle to the supports. By mid-March, 32 Endcap modules, 50% of the total with a weight of 350 Tn were pre-assembled in bldg. 185 at CERN. At this stage the assembly is inside its geometrical envelope and the tooling and procedures have been developed. The ATLAS Tile Calorimeter is composed of 3 cylinders ("barrels") of steel, scintillating tiles and optical fibers, altogether about 12 m long, with an outer diameter of 8.4 m, inner diameter of 4.5 m and weighing about 2800 tons. The central cavity will contain the Liquid Argon cryostats, and the whole calorimetry system will measure the direction and energy of jets produced at the LHC, as well as the missing transverse energy, which - as everyone knows - is one of the telltale signals of new and exciting physics. Each of the three cylinders is divid...

  7. EMC3-EIRENE modeling of toroidally-localized divertor gas injection experiments on Alcator C-Mod

    Energy Technology Data Exchange (ETDEWEB)

    Lore, J.D., E-mail: lorejd@ornl.gov [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Reinke, M.L. [York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); LaBombard, B. [Plasma Science and Fusion Center, MIT, Cambridge, MA 02139 (United States); Lipschultz, B. [York Plasma Institute, Department of Physics, University of York, Heslington, York YO10 5DD (United Kingdom); Churchill, R.M. [Plasma Science and Fusion Center, MIT, Cambridge, MA 02139 (United States); Pitts, R.A. [ITER Organization, Route de Vinon sur Verdon, 13115 Saint Paul Lez Durance (France); Feng, Y. [Max Planck Institute for Plasma Physics, Greifswald (Germany)

    2015-08-15

    Experiments on Alcator C-Mod with toroidally and poloidally localized divertor nitrogen injection have been modeled using the three-dimensional edge transport code EMC3-EIRENE to elucidate the mechanisms driving measured toroidal asymmetries. In these experiments five toroidally distributed gas injectors in the private flux region were sequentially activated in separate discharges resulting in clear evidence of toroidal asymmetries in radiated power and nitrogen line emission as well as a ∼50% toroidal modulation in electron pressure at the divertor target. The pressure modulation is qualitatively reproduced by the modeling, with the simulation yielding a toroidal asymmetry in the heat flow to the outer strike point. Toroidal variation in impurity line emission is qualitatively matched in the scrape-off layer above the strike point, however kinetic corrections and cross-field drifts are likely required to quantitatively reproduce impurity behavior in the private flux region and electron temperatures and densities directly in front of the target.

  8. DAQ INSTALLATION IN USC COMPLETED

    CERN Multimedia

    A. Racz

    After one year of work at P5 in the underground control rooms (USC55-S1&S2), the DAQ installation in USC55 is completed. The first half of 2006 was dedicated to the DAQ infrastructures installation (private cable trays, rack equipment for a very dense cabling, connection to services i.e. water, power, network). The second half has been spent to install the custom made electronics (FRLs and FMMs) and place all the inter-rack cables/fibers connecting all sub-systems to central DAQ (more details are given in the internal pages). The installation has been carried out by DAQ group members, coming from the hardware and software side as well. The pictures show the very nice team spirit !

  9. Installation of the Gbar LINAC

    CERN Multimedia

    Maximilien, Brice

    2017-01-01

    Installation of the GBAR linac in its shielding bunker. The electrons accelerated to 10 MeV toward a target will produce the positrons that are necessary to form anti hydrogen with the antiprotons coming from the ELENA decelerator.

  10. Solar Installation Labor Market Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, B.; Jordan, P.; Carrese, J.

    2011-12-01

    The potential economic benefits of the growing renewable energy sector have led to increased federal, state, and local investments in solar industries, including federal grants for expanded workforce training for U.S. solar installers. However, there remain gaps in the data required to understand the size and composition of the workforce needed to meet the demand for solar power. Through primary research on the U.S. solar installation employer base, this report seeks to address that gap, improving policymakers and other solar stakeholders understanding of both the evolving needs of these employers and the economic opportunity associated with solar market development. Included are labor market data covering current U.S. employment, expected industry growth, and employer skill preferences for solar installation-related occupations. This study offers an in-depth look at the solar installation sectors. A study published by the Solar Foundation in October 2011 provides a census of labor data across the entire solar value chain.

  11. The Status of LIGO Installation and Commissioning

    Science.gov (United States)

    Raab, Frederick J.

    2002-12-01

    LIGO is engaged in installation and commissioning in Hanford and Livingston. We are commissioning the first instance of any subsystem installed, applying lessons learned to later installations. We have installed all seismic stacks, installed lasers and input optics at both observatories and we have operated both of the 2-km Fabry-Perot cavities at Hanford, with lock times up to 10 hrs.

  12. Suitcase to Audit Solar Installations

    Energy Technology Data Exchange (ETDEWEB)

    Alberdi, J.; Barcala, J.M.; Blas de, J.; Molinero, A.; Navarrete, J.J.; Yuste, C.

    2001-07-01

    The audit suitcase was proposed by BESEL to introduce in the solar energy market a new tool which can make an evaluation of solar installation efficiency. Non-invasive sensors and low power components permit both easy installation of the devices and data storage for a period as long as ten days. This project was funded by the contract JOR3-CT98-7030 of the European Union JOULE III program. (Author)

  13. Countering Terrorism on Military Installations

    Science.gov (United States)

    1977-07-29

    enforcement purposes. Installation Provost Marshal should review the installation Tables of Distribucion and Allowances to determine commercial items of law...terrorist acts occurring within the 50 U.S. states, territor- ies, and possessions (including the Panama Canal Zone) rests with the Federal Bureadu...nence of the threat is difficult to predict. Today I estimate the threat as relatively low. S- In the Panama Canal Zone there could be three threats. One

  14. Recent JET experiments on Alfven eigenmodes with intermediate toroidal mode numbers: measurements and modelling of n=3 toroidal Alfven eigenmodes with the TAEFL code

    Energy Technology Data Exchange (ETDEWEB)

    Testa, D. [CRPP, Switzerland; Spong, Donald A [ORNL; Panis, T. [CRPP, Switzerland; Blanchard, P. [CRPP, Switzerland; Fasoli, A. [CRPP, Switzerland

    2011-01-01

    This paper reports the results of recent experiments performed on the JET tokamak on Alfven eigenmodes (AEs) with toroidal mode number (n) in the range n = 3-15. The stability properties of these medium-n AEs are investigated experimentally using a new set of compact in-vessel antennas, providing a direct and real-time measurement of the frequency, damping rate and amplitude for each individual toroidal mode number. We report here the quantitative analysis of the measurements of the damping rate for stable n = 3 toroidal AEs as a function of the edge plasma elongation, and the theoretical analysis of these data with the TAEFL code. The TAEFL results are in excellent qualitative agreement with the measurements, reproducing well the experimental scaling of increasing damping rate versus increasing edge elongation, and in many cases are also quantitatively correct, with a difference with respect to the measurements below 30%, particularly for magnetic configurations that have a larger edge magnetic shear.

  15. ATLAS electromagnetic end-cap detector

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    After the insertion of the first end-cap into this cryostat, the team proceed to the wiring operations. Millions of wires are connected to the electromagnetic calorimeter on this end-cap, whch must be carefully fed out from the detector so that data can be read out. The energy of photons, electrons and positrons will be measured as they pass through the end-cap having been created along the line of the beams in the proton-proton collisions.

  16. Hall Equilibria: Solutions with toroidal and poloidal magnetic fields in Neutron Star Crusts

    CERN Document Server

    Gourgouliatos, K N; Lyutikov, M; Reisenegger, A

    2013-01-01

    We present Hall equilibrium solutions for neutron stars crusts containing toroidal and poloidal magnetic field. Some simple cases are solved analytically while more complicated configurations are found numerically through a Gauss-Seidel elliptic partial differential equation solver.

  17. Three Cycles of the Solar Toroidal Magnetic Field and This Peculiar Minimum

    CERN Document Server

    Lo, Leyan; Scherrer, Phil

    2010-01-01

    Thirty-four years of WSO (Wilcox Solar Observatory) and thirteen years of SOHO/MDI (Michelson Doppler Imager on the Solar and Heliospheric Observatory) magnetograms have been studied to measure the east-west inclination angle, indicating the toroidal component of the photospheric magnetic field. This analysis reveals that the large-scale toroidal component of the global magnetic field is antisymmetric around the equator and reverses direction in regions associated with flux from one solar cycle compared to the next. The toroidal field revealed the first early signs of cycle 24 at high latitudes, especially in the northern hemisphere, appearing as far back as 2003 in the WSO data and 2004 in MDI. As in previous cycles, the feature moves gradually equatorward. Cycles overlap and the pattern associated with each cycle lasts about 17 years. Even though the polar field at the current solar minimum is significantly lower than the three previous minima, the toroidal field pattern is similar.

  18. Evolution of views on the structure of the ambipolar electric field in toroidal magnetic confinement systems

    Energy Technology Data Exchange (ETDEWEB)

    Kovrizhnykh, L. M., E-mail: lmkov@fpl.gpi.ru [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation)

    2015-12-15

    Various methods of determining the ambipolar electric field in toroidal magnetic systems (predominantly, in stellarators) and the evolution of views on this problem are discussed. Paradoxes encountered in solving this problem are analyzed, and ways of resolving them are proposed.

  19. TORQUE CAPACITY AND CONTACT EFFICIENCY OF A HALF TOROIDAL CONTINUOUSLY VARLABLE TRANSMISSIONS

    Institute of Scientific and Technical Information of China (English)

    Nabil Abdulla Attia; Qin Datong; Shi Wankai; Amir Ibrahim Ali

    2004-01-01

    The automotive industry is seeking new concepts for a continuously variable transmission (CVT) in the driveline. One possible solution for a CVT design is half toroidal traction drive, providing a high torque capacity with quick ratio change. An analytical study on the contact points of the half toroidal CVT has been detailed. The shapes of the contact areas among the input disk, power roller and output disk are considered ellipses. Mathematical equations for estimating the torque capacity, power loss due to spin action, and contact efficiency of the elliptical contacts of the half toroidal CVT are formulated and expressed in the form of integrals which can be readily evaluated by numerical scheme. The contact efficiency calculations of the half toroidal CVT have been developed for the proper spin point locations under the effect of system parameters. Numerical results are presented in graphical forms for considered parameters, which can help the designer to select the proper system parameters to minimize the undesirable spin effects.

  20. Calculation about a modification to the toroidal magnetic field of the Tokamak Novillo. Part I; Calculo sobre una modificacion al campo magnetico toroidal del Tokamak Novillo. Parte I

    Energy Technology Data Exchange (ETDEWEB)

    Chavez A, E.; Melendez L, L.; Colunga S, S.; Valencia A, R.; Lopez C, R.; Gaytan G, E

    1991-07-15

    The charged particles that constitute the plasma in the tokamaks are located in magnetic fields that determine its behavior. The poloidal magnetic field of the plasma current and the toroidal magnetic field of the tokamak possess relatively big gradients, which produce drifts on these particles. These drifts are largely the cause of the continuous lost of particles and of energy of the confinement region. In this work the results of numerical calculations of a modification to the 'traditional' toroidal magnetic field that one waits it diminishes the drifts by gradient and improve the confinement properties of the tokamaks. (Author)

  1. Injection of electron beam into a toroidal trap using chaotic orbits near magnetic null.

    Science.gov (United States)

    Nakashima, C; Yoshida, Z; Himura, H; Fukao, M; Morikawa, J; Saitoh, H

    2002-03-01

    Injection of charged particle beam into a toroidal magnetic trap enables a variety of interesting experiments on non-neutral plasmas. Stationary radial electric field has been produced in a toroidal geometry by injecting electrons continuously. When an electron gun is placed near an X point of magnetic separatrix, the electron beam spreads efficiently through chaotic orbits, and electrons distribute densely in the torus. The current returning back to the gun can be minimized less than 1% of the total emission.

  2. The turbulent diffusion of toroidal magnetic flux as inferred from properties of the sunspot butterfly diagram

    Science.gov (United States)

    Cameron, R. H.; Schüssler, M.

    2016-06-01

    Context. In order to match observed properties of the solar cycle, flux-transport dynamo models require the toroidal magnetic flux to be stored in a region of low magnetic diffusivity, typically located at or below the bottom of the convection zone. Aims: We infer the turbulent magnetic diffusivity affecting the toroidal field on the basis of empirical data. Methods: We considered the time evolution of mean latitude and width of the activity belts of solar cycles 12-23 and their dependence on cycle strength. We interpreted the decline phase of the cycles as a diffusion process. Results: The activity level of a given cycle begins to decline when the centers of its equatorward propagating activity belts come within their (full) width (at half maximum) from the equator. This happens earlier for stronger cycles because their activity belts are wider. From that moment on, the activity and the belt width decrease in the same manner for all cycles, independent of their maximum activity level. In terms of diffusive cancellation of opposite-polarity toroidal flux across the equator, we infer the turbulent diffusivity experienced by the toroidal field, wherever it is located, to be in the range 150-450 km2 s-1. Strong diffusive latitudinal spreading of the toroidal flux underneath the activity belts can be inhibited by an inflow toward the toroidal field bands in the convection zone with a magnitude of several meters per second. Conclusions: The inferred value of the turbulent magnetic diffusivity affecting the toroidal field agrees, to order of magnitude, with estimates based on mixing-length models for the solar convection zone. This is at variance with the requirement of flux-transport dynamo models. The inflows required to keep the toroidal field bands together before they approach the equator are similar to the inflows toward the activity belts observed with local helioseismology.

  3. Influence of toroidal effects on the stability of the internal kink mode

    Energy Technology Data Exchange (ETDEWEB)

    Galvao, R.M.O.; Sakanaka, P.H.; Shigueoka, H.

    1978-09-25

    Using the sigma-stability technique, we study the stability of the internal kink mode in toroidal geometry. We show that there are two unstable regions separated by a stable on in a ..beta..-q/sub c/ stability diagram. In one of these regions toroidal effects are stabilizing and in the other they are destabilizing. Discrepant results of previous analytical theories and experimental results are explained.

  4. Reference Magnetic Coordinates (RMC) for toroidal confinement systems

    Science.gov (United States)

    Zakharov, Leonid; Kolemen, Egemen; Lazerson, Samuel

    2012-03-01

    Because of intrinsic anisotropy of high temperature plasma with respect to magnetic field, use of proper coordinates is of high priority for both theory and numerical methods. While in axisymmetric case, the poloidal flux function Y(r,z)=const determines proper flux coordinates, in 3-D, such a function does not exist. The destruction of nested magnetic surfaces even by small 3-D perturbations leads to a sudden change of topology of magnetic field. As a result, the coordinate systems can no longer be based on tracing the magnetic field lines resulting in difficulties for theory and 3-D numerical simulations. The RMC coordinates a,θ,ζ presented here (introduced in 1998 but not really used) are nested toroidal coordinates, which are best aligned with an ergodic confinement fields. In particular, in RMC the vector potential of the magnetic field has an irreducible form A = φ00(a)∇θ +[Y00(a) +ψ^*(a,θ,ζ)]∇ζ , where 3-D function ψ^* contains only resonant Fourier harmonics of angle coordinates. RMC can be generated and advanced using a fast (Newton) algorithm not involving the field line tracing.

  5. Tokamak equilibria with strong toroidal current density reversal

    Science.gov (United States)

    Ludwig, G. O.; Rodrigues, Paulo; Bizarro, João P. S.

    2013-05-01

    The equilibrium of large magnetic islands in the core of a tokamak under conditions of strong toroidal current density reversal is investigated by a new method. The method uses distinct spectral representations to describe each simply connected region as well as the containing shell geometry. This ideal conducting shell may substitute for the plasma edge region or take a virtual character representing the external equilibrium field effect. The internal equilibrium of the islands is solved within the framework of the variational moment method. Equivalent surface current densities are defined on the boundaries of the islands and on the thin containing shell, giving a straightforward formulation to the interaction between regions. The equilibrium of the island-shell system is determined by matching moments of the Dirichlet boundary conditions. Finally, the macroscopic stability against a class of tilting displacements is examined by means of an energy principle. It is found out that the up-down symmetric islands are stable to this particular perturbation and geometry but the asymmetric system presents a bifurcation in the equilibrium.

  6. Thomson scattering diagnostic on the Compact Toroidal Hybrid Experiment

    Science.gov (United States)

    Traverso, Peter; Maurer, D. A.; Ennis, D. A.; Hartwell, G. J.

    2016-10-01

    A Thomson scattering system is being commissioned for the non-axisymmetric plasmas of the Compact Toroidal Hybrid (CTH), a five-field period current-carrying torsatron. The system takes a single point measurement at the magnetic axis to both calibrate the two- color soft x-ray Te system and serve as an additional diagnostic for the V3FIT 3D equilibrium reconstruction code. A single point measurement will reduce the uncertainty in the reconstructed peak pressure by an order of magnitude for both current-carrying plasmas and future gyrotron-heated stellarator plasmas. The beam, generated by a frequency doubled Continuum 2 J, Nd:YaG laser, is passed vertically through an entrance Brewster window and a two-aperture optical baffle system to minimize stray light. The beam line propagates 8 m to the CTH device mid-plane with the beam diameter < 3 mm inside the plasma volume. Thomson scattered light is collected by two adjacent f/2 plano-convex condenser lenses and focused onto a custom fiber bundle. The fiber is then re-bundled and routed to a Holospec f/1.8 spectrograph to collect the red-shifted scattered light from 535-565 nm. The system has been designed to measure plasmas with core Te of 100 to 200 eV and densities of 5 ×1018 to 5 ×1019 m-3. Work supported by USDOE Grant DE-FG02-00ER54610.

  7. LQR Controller for Toroidal Continuously Variable Transmission in Reverse Motion

    Science.gov (United States)

    Mensler, Michel; Kawabe, Taketoshi; Joe, Shinichiro

    The system considered in this paper is a Toroidal Continuously Variable Transmission (TCVT) system for cars. This system is unstable in reverse motion as some mechanical parts have been removed from the original one for cost reduction, and the gear ratio has to be regulated around its nominal value for car reverse motion. The control theory used here is the Linear Quadratic Regulator (LQR) associated to a gain-scheduling technique, as the TCVT system is nonlinear according to the car speed. Moreover, as the LQR method requires the entire TCVT state vector and as the only available signal is the gear ratio, a full-order observer is designed. In order to take the other nonlinearities of the system into account, the observer is nonlinear: a diffeomorphism is then used for converting the variables provided by the nonlinear observer into the needed variables. In order to verify the effectiveness and the robustness of the controller against the car speed and the torque shift disturbance phenomenon, several experiments with a test-bed and with an actual vehicle have been performed and showed the efficiency of the proposed controller.

  8. Control of Compact-Toroid Characteristics by External Copper Shell

    Science.gov (United States)

    Matsumoto, T.; Sekiguchi, J.; Asai, T.; Gota, H.; Roche, T.; Allfrey, I.; Cordero, M.; Garate, E.; Kinley, J.; Valentine, T.; Waggoner, W.; the TAE Team

    2015-11-01

    A collaborative research project by Tri Alpha Energy and Nihon University has been conducted for several years, which led to the development of a new compact toroid (CT) injector for efficient FRC particle refueling in the C-2U experiment. The CT is formed by a magnetized coaxial plasma gun (MCPG), consisting of coaxial cylindrical electrodes. In CT formation via MCPG, the magnetic helicity content of the generated CT is one of the critical parameters. A bias coil is inserted into the inner electrode to generate a poloidal flux. The resultant bias magnetic field is spread out of MCPG with time due to its low-frequency bias current. To obtain a more effectively distributed bias magnetic field as well as to improve the voltage breakdown between electrodes, the MCPG incorporates a novel ~ 1 mm thick copper shell mounted outside of the outer electrode. This allows for reliable and controlled operation and more robust CT generation. A detailed discussion of the copper shell and experimental test results will be presented.

  9. Validation of Helium Inlet Design for ITER Toroidal Field Coil

    CERN Document Server

    Boyer, C; Hamada, K; Foussat, A; Le Rest, M; Mitchell, N; Decool, P; Savary, F; Sgobba, S; Weiss, K-P

    2014-01-01

    The ITER organization has performed design and its validation tests on a helium inlet structure for the ITER Toroidal Field (TF) coil under collaboration with CERN, KIT, and CEA-Cadarache. Detailed structural analysis was performed in order to optimize the weld shape. A fatigue resistant design on the fillet weld between the shell covers and the jacket is an important point on the helium inlet structure. A weld filler material was selected based on tensile test at liquid helium temperature after Nb3Sn reaction heat treatment. To validate the design of the weld joint, fatigue tests at 7 K were performed using heat-treated butt weld samples. A pressure drop measurement of a helium inlet mock-up was performed by using nitrogen gas at room temperature in order to confirm uniform flow distribution and pressure drop characteristic. These tests have validated the helium inlet design. Based on the validation, Japanese and European Union domestic agencies, which have responsibilities of the TF coil procurement, are pr...

  10. Global theory to understand toroidal drift waves in steep gradient

    Science.gov (United States)

    Xie, Hua-sheng; Li, Bo

    2016-08-01

    Toroidal drift waves with unconventional mode structures and non-ground eigenstates, which differ from a typical ballooning structure mode, are found to be important recently by large scale global gyrokinetic simulations and especially become dominant at strong gradient edge plasmas [cf. H. S. Xie and Y. Xiao, Phys. Plasmas 22, 090703 (2015)]. The global stability and mode structures of drift wave in this steep edge density and temperature gradients are examined by both direct numerical solutions of a model two-dimensional eigen equation and analytical theory employing WKB-ballooning approach. Theory agrees with numerical solutions quite well. Our results indicate that (i) non-ground eigenstates and unconventional mode structures generally exist and can be roughly described by two parameters "quantum number" l and ballooning angle ϑk , (ii) local model can overestimate the growth rate largely, say, >50 % , and (iii) the narrow steep equilibrium profile leads to twisting (triangle-like) radial mode structures. With velocity space integral, semi-local theory predicts that the critical jump gradient of the most unstable ion temperature gradient mode from ground state l = 0 to non-ground state l = 1 is LT-1R ˜50 . These features can have important consequences to turbulent transport.

  11. First assembly phase for the ATLAS toroid coils

    CERN Multimedia

    Patrice Loïez

    2003-01-01

    The ATLAS barrel toroid system consists of eight coils, each of axial length 25.3 m, assembled radially and symmetrically around the beam axis. The coils are of a flat racetrack type with two double-pancake windings made of 20.5 kA aluminium-stabilized niobium-titanium superconductor. In the first phase of assembly, the two 'pancakes' are packed into their vacuum vessel. This is done using bladders filled with resin and glass microbeads under pressure. The resin is heated and, once cooled, holds the pancakes in place. The operation has to be performed on both sides of the coil, which necessitated a special technique to turn the coils over and then transport them to the heating table. Photos 01, 02, 03: Use of the overhead travelling crane to hoist the coil up and then tilt it over, the coil frame's metal feet being used as rotational pivots, supporting half the coil's weight. Once it has been turned over, the coil, now with only half the frame, is transported to the heating table using a special lifting gant...

  12. Toroidal and poloidal magnetic fields at Venus. Venus Express observations

    Science.gov (United States)

    Dubinin, E.; Fraenz, M.; Woch, J.; Zhang, T. L.; Wei, Y.; Fedorov, A.; Barabash, S.; Lundin, R.

    2013-10-01

    Magnetic field and plasma measurements carried out onboard Venus Express during solar minimum conditions suggest the existence of two kinds of magnetic field configuration in the Venusian ionosphere. We interpret these as the manifestation of two different types of generation mechanisms for the induced magnetosphere. A different magnetic field topology (toroidal and poloidal) arises if the induced currents are driven either by the solar wind motional electric field or by the Faraday electric field—a conducting ionosphere sees the magnetic field carried by solar wind as a time-varying field. At the dayside, both driving agents produce a similar draping pattern of the magnetic field. However, different magnetic field signatures inherent to both induction mechanisms appear at lower altitudes in the terminator region. The conditions at low solar EUV flux when the ionosphere of Venus becomes magnetized seem to be favorable to distinguish between two different types of the induced fields. We present cases of both types of the magnetic field topology. The cases when the effects of the Faraday induction become well noticeable are especially interesting since they provide us with an example of solar wind interaction with a tiny induced dipole field immersed into the ionosphere. Another interesting case when poloidal magnetic fields are evidently displayed is observed when the IMF vector is almost aligned with the solar wind velocity. In general case, both mechanisms of induction probably complement each other.

  13. Worming Their Way into Shape: Toroidal Formations in Micellar Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Cardiel Rivera, Joshua J.; Tonggu, Lige; Dohnalkova, Alice; de la Iglesia, Pablo; Pozzo, Danilo C.; Shen, Amy

    2013-11-01

    We report the formation of nanostructured toroidal micellar bundles (nTMB) from a semidilute wormlike micellar solution, evidenced by both cryogenicelectron microscopy and transmission electron microscopy images. Our strategy for creating nTMB involves a two-step protocol consisting of a simple prestraining process followed by flow through a microfluidic device containing an array of microposts, producing strain rates in the wormlike micelles on the order of 105 s^1. In combination with microfluidic confinement, these unusually large strain rates allow for the formation of stable nTMB. Electron microscopy images reveal a variety of nTMB morphologies and provide the size distribution of the nTMB. Small-angle neutron scattering indicates the underlying microstructural transition from wormlike micelles to nTMB. We also show that other flow-induced approaches such as sonication can induce and control the emergence of onion-like and nTMB structures, which may provide a useful tool for nanotemplating.

  14. Behavior of Compact Toroid in the External Magnetic Fields

    Science.gov (United States)

    Fukumoto, N.; Ioroi, A.; Nagata, M.; Uyama, T.

    1999-11-01

    We have investigated the possibility of refueling and density control of tokamak plasmas by the spheromak-type Compact Toroid (CT) injection in the JFT-2M tokamak in collaboration with JAERI. We demonstrated the CT injection into OH plasmas and observed the core penetration at B_T=0.8 T. The tokamak electron density increased ~0.2× 10^19m-3 at a rate of 2× 10^21m-3/s. We also observed the decrease of the CT velocity by the external magnetic field of the tokamak, which is applied across the CT acceleration region. We have examined the behavior of the CT translated in the external fields B_ext using the magnetic probes and the fast framing camera at Himeji Inst. of tech.. CT plasma in the acceleration region is deformed by the Lorentz force of Jg × B_ext, where Jg is the gun current for CT acceleration. The magnetic field structures of a long CT in the drift region has been revealed to be the mixed relaxed state of m=0 and m=1. Results from CT acceleration and injection in a transverse field will be presented.

  15. Deconfinement in Yang-Mills Theory through Toroidal Compactification

    Energy Technology Data Exchange (ETDEWEB)

    Simic, Dusan; Unsal, Mithat; /Stanford U., Phys. Dept. /SLAC

    2011-08-12

    We introduce field theory techniques through which the deconfinement transition of four-dimensional Yang-Mills theory can be moved to a semi-classical domain where it becomes calculable using two-dimensional field theory. We achieve this through a double-trace deformation of toroidally compactified Yang-Mills theory on R{sup 2} x S{sub L}{sup 1} x S{sub {beta}}{sup 1}. At large N, fixed-L, and arbitrary {beta}, the thermodynamics of the deformed theory is equivalent to that of ordinary Yang-Mills theory at leading order in the large N expansion. At fixed-N, small L and a range of {beta}, the deformed theory maps to a two-dimensional theory with electric and magnetic (order and disorder) perturbations, analogs of which appear in planar spin-systems and statistical physics. We show that in this regime the deconfinement transition is driven by the competition between electric and magnetic perturbations in this two-dimensional theory. This appears to support the scenario proposed by Liao and Shuryak regarding the magnetic component of the quark-gluon plasma at RHIC.

  16. Pareto optimal design of sectored toroidal superconducting magnet for SMES

    Science.gov (United States)

    Bhunia, Uttam; Saha, Subimal; Chakrabarti, Alok

    2014-10-01

    A novel multi-objective optimization design approach for sectored toroidal superconducting magnetic energy storage coil has been developed considering the practical engineering constraints. The objectives include the minimization of necessary superconductor length and torus overall size or volume, which determines a significant part of cost towards realization of SMES. The best trade-off between the necessary conductor length for winding and magnet overall size is achieved in the Pareto-optimal solutions, the compact magnet size leads to increase in required superconducting cable length or vice versa The final choice among Pareto optimal configurations can be done in relation to other issues such as AC loss during transient operation, stray magnetic field at outside the coil assembly, and available discharge period, which is not considered in the optimization process. The proposed design approach is adapted for a 4.5 MJ/1 MW SMES system using low temperature niobium-titanium based Rutherford type cable. Furthermore, the validity of the representative Pareto solutions is confirmed by finite-element analysis (FEA) with a reasonably acceptable accuracy.

  17. Electron cyclotron heating and current drive in toroidal geometry

    Energy Technology Data Exchange (ETDEWEB)

    Kritz, A.H.

    1991-11-01

    The Principal Investigator has continued to work on problems associated both with the deposition and with the emission of electron cyclotron power in toroidal plasmas. We have investigated the use of electron cyclotron resonance heating for bringing compact tokamaks (BPX) to ignition-like parameters. This requires that we continue to refine the modeling capability of the TORCH code linked with the BALDUR 1 {1/2} D transport code. Using this computational tool, we have examined the dependence of ignition on heating and transport employing both theoretical (multi-mode) and empirically based transport models. The work on current drive focused on the suppression of tearing modes near the q = 2 surface and sawteeth near the q = 1 surface. Electron cyclotron current drive in CIT near the q =2 surface was evaluated for a launch scenario where electron cyclotron power was launched near the equatorial plane. The work on suppression of sawteeth has been oriented toward understanding the suppression that has been observed in a number of tokamaks, in particular, in the WT-3 tokamak in Kyoto. To evaluate the changes in current profile (shear) near the q =1 surface, simulations have been carried out using the linked BALDUR-TORCH code. We consider effects on shear resulting both from wave-induced current as well as from changes in conductivity associated with changes in local temperature. Abstracts and a paper relating to this work is included in Appendix A.

  18. First qualification of ITER Toroidal Field Coil conductor jacketing

    Energy Technology Data Exchange (ETDEWEB)

    Hamada, Kazuya, E-mail: hamada.kazuya@jaea.go.jp [Japan Atomic Energy Agency (Japan); Takahashi, Yoshikazu; Isono, Takaaki; Nunoya, Yoshihiko; Matsui, Kunihiro; Kawano, Katsumi; Oshikiri, Masayuki; Tsutsumi, Fumiaki; Koizumi, Norikiyo; Nakajima, Hideo; Okuno, Kiyoshi [Japan Atomic Energy Agency (Japan); Matsuda, Hidemitsu; Yano, Yoshitaka [Nippon Steel Engineering Co. Ltd (Japan); Devred, Arnauld; Bessette, Denis [ITER Organization (France)

    2011-10-15

    The Japan Atomic Energy Agency (JAEA) has the responsibility to procure 25% of the ITER Toroidal Field Coil conductors as the Japanese Domestic Agency (JADA) in the ITER project. The TF conductor is a circular shaped, cable-in-conduit conductor, composed of a cable and a stainless steel conduit (jacket). The outer diameter and maximum length of the TF conductor are 43.7 mm and 760 m, respectively. JAEA started to produce strand, cables and jacket sections and to construct a conductor manufacturing (jacketing) facility in 2008. Following preparation in December 2009 of the jacketing facility, the dummy cable, the jacket sections and fabrication procedures, such as welding, cable insertion, compaction and spooling, JAEA manufactured a 760 m long Cu dummy conductor for process qualification. Into the 760 m long Cu dummy conductor jacketing, JAEA successfully inserted the cable with a maximum force of 32 kN. The outer diameter of the cross section of the spooled conductor was 43.7 {+-} 0.15 mm, which complies with the ITER target requirement of 43.7 {+-} 0.3 mm. Following qualification of all manufacturing processes, JAEA has started to fabricate superconducting conductors for the TF coils.

  19. The ATALANTE installation; L'installation atalante

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-10-01

    In the Atalante installation of the CEA/Marcoule, researches on the reprocessing of irradiated fuel from nuclear reactors, are performed. In the framework of the law (30 december 1991) on the public policy concerning the radioactive wastes management, the ATALANTE project has to proposed solutions for the long-dated management of these wastes and to help the reprocessing industry. The specifications of the installation and the research programs are detailed with a special interest for the glass durability and the plutonium purifying cycle. The public policy stakes are also recalled. (A.L.B.)

  20. Nature mangement, landscape and the CAP

    NARCIS (Netherlands)

    Brouwer, F.M.; Godeschalk, F.E.

    2004-01-01

    The integration of nature management, landscape and environmental concerns into the Common Agricultural Policy (CAP) has gained momentum with the CAP reforms adopted in June 2003. The report explores instruments and approaches that contribute to the inte-gration of nature conservation and landscape

  1. ALEPH end-cap and barrel

    CERN Multimedia

    Patrice Loiez

    1993-01-01

    The end-cap is pulled away from the barrel on the ALEPH detector so that the hadronic calorimeter and muon chambers are revealed. The end-cap maximises the data available from particles produced along the direction of the beam. The workers on the inner part of the detector give a sense of scale.

  2. Inductive Eigenmodes of a resistive toroidal surface in vacuum

    Energy Technology Data Exchange (ETDEWEB)

    Lo Surdo, C. [ENEA, Centro Ricerche Frascati, Rome (Italy). Dipt. Innovazione

    1999-07-01

    In this paper it has been studied the Electro-Magnetic (EM) Eigenmodes, sufficiently slow as to legitimate the pre-Maxwell approximation of Maxwell's system (or inductive Eigenmodes), of a given smooth, toroidal-un knotted, electrically resistive surface {tau} with given smooth (surface) resistivity 0 < {rho}{sub d}egree < {infinity}, and lying in the (empty) R{sup 3}. Within the above limitations (to be made more precise), the geometry of {tau} is arbitrary. With the eigenvalue associated with the generic Eigenmode being defined as the opposite of its logarithmic time-derivative, one expects that the resulting spectrum be discrete and strictly positive. It shall be interested into the degenerate case where {tau} be cut (i.e. electrically broken) along one or more of its irreducible cycles. This case will be analyzed autonomously, rather than as a limit (for {rho}{sub d}egree {yields} {infinity} along the cuts) of the regular case. Without cuts, the Eigenproblem under consideration is nothing but the two-dimensional (2-dim) generalization of the classical case of a smooth, unknotted, electrically conductive, simple coil in infinite vacuum. Its analysis hinges on the classical potential theory, and turns out to be a special application of the linear, integrodifferential (elliptic) equation theory on a compact, multiply connected, 2-dim manifold. The attention and approach will be confined to strong (or classical) solutions, both in {tau} and C {tau} = R{sup 3} / {tau}. This study is divided in two parts: a General Part (Sects 1 divided 4) is devoted to the case of generic {tau} and {rho}{sub d}egree (within the convenient smoothness requirements), whereas a Special Part (Sects 5 divided 7) deals with the (more or less formal) discussion of a couple of particular cases ({tau} {identical_to} a canonical torus), both of which with uniform {rho}{sub d}egree. Some propaedeutical/supplementary information is provided in a number of Appendices. [Italian] Il presente

  3. Ferromagnetism of polythiophene-capped Au nanoparticles

    Science.gov (United States)

    Suzuki, K.; Zhang, H.; Saito, K.; Garitaonandia, J. S.; Goikolea, E.; Insausti, M.

    2011-04-01

    The magnetic and electrical transport properties of regioregular poly(3-hexylthiophene)-capped Au nanoparticles (NPs) doped with iodine have been investigated to clarify the effectiveness of conductive polymer capping on the induction of ferromagnetism in Au. The room-temperature magnetization curve of the undoped polythiophene-capped Au NPs exhibits a clear hysteresis behavior with a coercive force of 160 Oe. The spontaneous magnetization normalized by the mass of Au is 2.0 × 10-2 emu/g. The spontaneous magnetization was found virtually unaffected by iodine doping, whereas the electrical conductivity is enhanced dramatically to ˜10 S/cm. Our results show that polythiophene capping could lead to spontaneous magnetic polarization in Au NPs, and the conductivity of the polymer capping does not affect the ferromagnetism of the Au nanoparticles, opening a possibility for further investigation into the magnetotransport behavior of ferromagnetic Au NPs.

  4. An automatic system for controlling the quality of straws installed in the ATLAS TRT detector

    CERN Document Server

    Golunov, A O; Gousakov, Yu V; Kekelidze, G D; Livinski, V V; Mouraviev, S V; Parzycki, S S; Peshekhonov, V D; Price, M J; Savenkov, A A

    2004-01-01

    This article describes an automatic system to control the quality of straws installed in the wheels of the end-cap Transition Radiation Tracker of the ATLAS experiment. The system tests both the straightness and the electrical insulation of the straws during installation. The testing time per straw is 9s; consequently it takes about 2h to measure one layer of straws. The off-line analysis takes 20s per straw. With this system defects can be immediately detected and corrected. This clearly influences the future performance of the detector.

  5. Transport bifurcation induced by sheared toroidal flow in tokamak plasmasa)

    Science.gov (United States)

    Highcock, E. G.; Barnes, M.; Parra, F. I.; Schekochihin, A. A.; Roach, C. M.; Cowley, S. C.

    2011-10-01

    First-principles numerical simulations are used to describe a transport bifurcation in a differentially rotating tokamak plasma. Such a bifurcation is more probable in a region of zero magnetic shear than one of finite magnetic shear, because in the former case the component of the sheared toroidal flow that is perpendicular to the magnetic field has the strongest suppressing effect on the turbulence. In the zero-magnetic-shear regime, there are no growing linear eigenmodes at any finite value of flow shear. However, subcritical turbulence can be sustained, owing to the existence of modes, driven by the ion temperature gradient and the parallel velocity gradient, which grow transiently. Nonetheless, in a parameter space containing a wide range of temperature gradients and velocity shears, there is a sizeable window where all turbulence is suppressed. Combined with the relatively low transport of momentum by collisional (neoclassical) mechanisms, this produces the conditions for a bifurcation from low to high temperature and velocity gradients. A parametric model is constructed which accurately describes the combined effect of the temperature gradient and the flow gradient over a wide range of their values. Using this parametric model, it is shown that in the reduced-transport state, heat is transported almost neoclassically, while momentum transport is dominated by subcritical parallel-velocity-gradient-driven turbulence. It is further shown that for any given input of torque, there is an optimum input of heat which maximises the temperature gradient. The parametric model describes both the behaviour of the subcritical turbulence (which cannot be modelled by the quasi-linear methods used in current transport codes) and the complicated effect of the flow shear on the transport stiffness. It may prove useful for transport modelling of tokamaks with sheared flows.

  6. First-principles approach to investigate toroidal property of magnetoelectric multiferroic GaFeO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Nie, Yung-mau, E-mail: ymnie@ncnu.edu.tw [Department of Applied Materials and Optoelectronic Engineering, National Chi Nan University (NCNU), Nantou County 54561, Taiwan (China)

    2016-01-14

    A first-principles approach incorporating the concept of toroidal moments as a measure of the spin vortex is proposed and applied to simulate the toroidization of magnetoelectric multiferroic GaFeO{sub 3}. The nature of space-inversion and time-reversal violations of ferrotoroidics is reproduced in the simulated magnetic structure of GaFeO{sub 3}. For undoped GaFeO{sub 3}, a toroidal moment of −22.38 μ{sub B} Å per unit cell was obtained, which is the best theoretical estimate till date. Guided by the spin vortex free-energy minimization perturbed by an externally applied field, it was discovered that the minority spin markedly biases the whole toroidization. In summary, this approach not only calculates the toroidal moment but provides a way to understand the toroidal nature of magnetoelectric multiferroics.

  7. Development of toroid-type HTS DC reactor series for HVDC system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kwangmin, E-mail: kwangmin81@gmail.com [Changwon National University, 55306 Sarim-dong, Changwon 641-773 (Korea, Republic of); Go, Byeong-Soo; Park, Hea-chul; Kim, Sung-kyu; Kim, Seokho [Changwon National University, 55306 Sarim-dong, Changwon 641-773 (Korea, Republic of); Lee, Sangjin [Uiduk University, Gyeongju 780-713 (Korea, Republic of); Oh, Yunsang [Vector Fields Korea Inc., Pohang 790-834 (Korea, Republic of); Park, Minwon; Yu, In-Keun [Changwon National University, 55306 Sarim-dong, Changwon 641-773 (Korea, Republic of)

    2015-11-15

    Highlights: • The authors developed the 400 mH, 400 A class toroid-type HTS DC reactor system. • The target temperature, inductance and operating current are under 20 K at magnet, 400 mH and 400 A, respectively. All target performances of the HTS DC reactor were achieved. • The HTS DC reactor was conducted through the interconnection operation with a LCC type HVDC system. • Now, the authors are studying the 400 mH, 1500 A class toroid-type HTS DC reactor for the next phase HTS DC reactor. - Abstract: This paper describes design specifications and performance of a toroid-type high-temperature superconducting (HTS) DC reactor. The first phase operation targets of the HTS DC reactor were 400 mH and 400 A. The authors have developed a real HTS DC reactor system during the last three years. The HTS DC reactor was designed using 2G GdBCO HTS wires. The HTS coils of the toroid-type DC reactor magnet were made in the form of a D-shape. The electromagnetic performance of the toroid-type HTS DC reactor magnet was analyzed using the finite element method program. A conduction cooling method was adopted for reactor magnet cooling. The total system has been successfully developed and tested in connection with LCC type HVDC system. Now, the authors are studying a 400 mH, kA class toroid-type HTS DC reactor for the next phase research. The 1500 A class DC reactor system was designed using layered 13 mm GdBCO 2G HTS wire. The expected operating temperature is under 30 K. These fundamental data obtained through both works will usefully be applied to design a real toroid-type HTS DC reactor for grid application.

  8. Horn installed in CNGS tunnel

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    The horn is installed for the CERN Neutrinos to Gran Sasso (CNGS) project. Protons collide with a graphite target producing charged particles that are focussed by the magnetic field in the horn. These particles will then pass into a decay tube where they decay into neutrinos, which travel towards a detector at Gran Sasso 732 km away in Italy.

  9. Temperature rise of installed FCC

    Science.gov (United States)

    Hankins, J. D.

    1976-01-01

    Report discusses temperature profiles of installed FCC for wood and tile surfaces. Three-conductor FCC was tested at twice nominal current-carrying capacity over bare floor and under carpet, with result indicating that temperature rise is not a linear function of current with FCC at this level.

  10. Make way for the ATLAS magnet

    CERN Multimedia

    2007-01-01

    On 5 and 6 February, the first ATLAS End Cap Toroid magnet was transported to begin a two-month regime of cryogenic testing. The magnet is scheduled to be installed in the cavern the first week of June.

  11. Development of toroid-type HTS DC reactor series for HVDC system

    Science.gov (United States)

    Kim, Kwangmin; Go, Byeong-Soo; Park, Hea-chul; Kim, Sung-kyu; Kim, Seokho; Lee, Sangjin; Oh, Yunsang; Park, Minwon; Yu, In-Keun

    2015-11-01

    This paper describes design specifications and performance of a toroid-type high-temperature superconducting (HTS) DC reactor. The first phase operation targets of the HTS DC reactor were 400 mH and 400 A. The authors have developed a real HTS DC reactor system during the last three years. The HTS DC reactor was designed using 2G GdBCO HTS wires. The HTS coils of the toroid-type DC reactor magnet were made in the form of a D-shape. The electromagnetic performance of the toroid-type HTS DC reactor magnet was analyzed using the finite element method program. A conduction cooling method was adopted for reactor magnet cooling. The total system has been successfully developed and tested in connection with LCC type HVDC system. Now, the authors are studying a 400 mH, kA class toroid-type HTS DC reactor for the next phase research. The 1500 A class DC reactor system was designed using layered 13 mm GdBCO 2G HTS wire. The expected operating temperature is under 30 K. These fundamental data obtained through both works will usefully be applied to design a real toroid-type HTS DC reactor for grid application.

  12. The pharmaceutical vial capping process: Container closure systems, capping equipment, regulatory framework, and seal quality tests.

    Science.gov (United States)

    Mathaes, Roman; Mahler, Hanns-Christian; Buettiker, Jean-Pierre; Roehl, Holger; Lam, Philippe; Brown, Helen; Luemkemann, Joerg; Adler, Michael; Huwyler, Joerg; Streubel, Alexander; Mohl, Silke

    2016-02-01

    Parenteral drug products are protected by appropriate primary packaging to protect against environmental factors, including potential microbial contamination during shelf life duration. The most commonly used CCS configuration for parenteral drug products is the glass vial, sealed with a rubber stopper and an aluminum crimp cap. In combination with an adequately designed and controlled aseptic fill/finish processes, a well-designed and characterized capping process is indispensable to ensure product quality and integrity and to minimize rejections during the manufacturing process. In this review, the health authority requirements and expectations related to container closure system quality and container closure integrity are summarized. The pharmaceutical vial, the rubber stopper, and the crimp cap are described. Different capping techniques are critically compared: The most common capping equipment with a rotating capping plate produces the lowest amount of particle. The strength and challenges of methods to control the capping process are discussed. The residual seal force method can characterize the capping process independent of the used capping equipment or CCS. We analyze the root causes of several cosmetic defects associated with the vial capping process.

  13. Capping stack: An industry in the making

    Institute of Scientific and Technical Information of China (English)

    Jack Chen; Li Xunke; Xie Wenhui; Kang Yongtian

    2013-01-01

    This paper gives an overview of recent development of the marine well containment system (MWCS)after BP Macondo subsea well blowout occurred on April 20,2010 in the Gulf of Mexico.Capping stack,a hardware utilized to contain blowout well at or near the wellhead is the center piece of MWCS.Accessibility to the dedicated capping stacks is gradually becoming a pre-requirement to obtain the permit for offshore drilling/workover,and the industry for manufacturing,maintenance,transportation and operation of the capping stack is in the making.

  14. Disc-Capped ZnO Nanocombs

    Institute of Scientific and Technical Information of China (English)

    LI Xin; XU chun-xiang; ZHU Guang-Ping; YANG Yi; LIU Jin-Ping; SUN Xiao-Wei; CUI Yi-Ping

    2007-01-01

    Nanocombs with a disc cap structure of ZnO have been synthesized on si substrates by using pure Zinc powders as the source materials based on a vapour-phase transport process.The morphology and the microstructure are investigated by a scanning electron microscopy and x-ray diffraction.Based on the transmission electron microscopy and selected area electron diffraction analysis,the growth directions of three representative parts,nanoribbon stem,nanorod branch and nanodisc cap of the nanocomb are revealed.The growth mechanism of the disc-capped nanocombs is discussed based on the self-catalyzed vapour-liquid-solid process.

  15. Quantum field theory on toroidal topology: Algebraic structure and applications

    Science.gov (United States)

    Khanna, F. C.; Malbouisson, A. P. C.; Malbouisson, J. M. C.; Santana, A. E.

    2014-05-01

    The development of quantum theory on a torus has a long history, and can be traced back to the 1920s, with the attempts by Nordström, Kaluza and Klein to define a fourth spatial dimension with a finite size, being curved in the form of a torus, such that Einstein and Maxwell equations would be unified. Many developments were carried out considering cosmological problems in association with particle physics, leading to methods that are useful for areas of physics, in which size effects play an important role. This interest in finite size effect systems has been increasing rapidly over the last decades, due principally to experimental improvements. In this review, the foundations of compactified quantum field theory on a torus are presented in a unified way, in order to consider applications in particle and condensed matter physics. The theory on a torus ΓDd=(S1)d×RD-d is developed from a Lie-group representation and c*c*-algebra formalisms. As a first application, the quantum field theory at finite temperature, in its real- and imaginary-time versions, is addressed by focusing on its topological structure, the torus Γ41. The toroidal quantum-field theory provides the basis for a consistent approach of spontaneous symmetry breaking driven by both temperature and spatial boundaries. Then the superconductivity in films, wires and grains are analyzed, leading to some results that are comparable with experiments. The Casimir effect is studied taking the electromagnetic and Dirac fields on a torus. In this case, the method of analysis is based on a generalized Bogoliubov transformation, that separates the Green function into two parts: one is associated with the empty space-time, while the other describes the impact of compactification. This provides a natural procedure for calculating the renormalized energy-momentum tensor. Self interacting four-fermion systems, described by the Gross-Neveu and Nambu-Jona-Lasinio models, are considered. Then finite size effects on

  16. Finite beta and compressibility effects on stability of resistive modes in toroidal geometry

    Energy Technology Data Exchange (ETDEWEB)

    Leboeuf, J.-N.G. [Oak Ridge National Lab., TN (United States); Kurita, Gen-ichi

    1998-03-01

    Linear resistive stability results obtained from the toroidal magnetohydrodynamic codes FAR developed at the Oak Ridge National Laboratory in United States of America and AEOLUS developed at the Japan Atomic Energy Research Institute are compared for carefully constructed benchmark profiles and parameters. These are unstable to a tearing mode with toroidal mode number n=1. The eigenvalues and eigenfunctions calculated with both codes are in close agreement and show that the effect of compressibility is weak for these modes. The effect of finite plasma beta is considered, and the eigenvalues calculated by the FAR and AEOLUS codes also show good agreement. It is shown that the finite beta has a stabilizing effect on the toroidal tearing mode, but that the compressibility also has little effect on finite beta tearing modes. (author)

  17. Current transformers with nanocrystalline alloy toroidal core: analytical, computational and experimental studies

    Directory of Open Access Journals (Sweden)

    Benedito Antonio Luciano

    2012-10-01

    Full Text Available In this paper are presented theoretical analysis and experimental results concerning the performance of toroidal cores used in current transformers. For most problems concerning transformers design, analytical methods are useful, but numerical methods provide a better understanding of the transformers electromagnetic behaviour. Numerical field solutions may be used to determine the electrical equivalent circuit parameters of toroidal core current transformers. Since the exciting current of current transformers alters the ratio and phase angle of primary and secondary currents, it is made as small as possible though the use of high permeability and low loss magnetic material in the construction of the core. According to experimental results presented in this work, in comparison with others soft magnetic materials, nanocrystalline alloys appear as the best material to be used in toroidal core for current transformers.

  18. Observations of toroidicity-induced Alfvén eigenmodes in a reversed field pinch plasma

    Science.gov (United States)

    Regnoli, G.; Bergsâker, H.; Tennfors, E.; Zonca, F.; Martines, E.; Serianni, G.; Spolaore, M.; Vianello, N.; Cecconello, M.; Antoni, V.; Cavazzana, R.; Malmberg, J.-A.

    2005-04-01

    High frequency peaks in the spectra of magnetic field signals have been detected at the edge of Extrap-T2R [P. R. Brunsell, H. Bergsåker, M. Cecconello, J. R. Drake, R. M. Gravestijn, A. Hedqvist, and J.-A. Malmberg, Plasma Phys. Controlled Fusion, 43, 1457 (2001)]. The measured fluctuation is found to be mainly polarized along the toroidal direction, with high toroidal periodicity n and Alfvénic scaling (f∝B/√mini ). Calculations for a reversed field pinch plasma predict the existence of an edge resonant, high frequency, high-n number toroidicity-induced Alfvén eigenmode with the observed frequency scaling. In addition, gas puffing experiments show that edge density fluctuations are responsible for the rapid changes of mode frequency. Finally a coupling with the electron drift turbulence is proposed as drive mechanism for the eigenmode.

  19. Optimization of Shielded PCB Air-Core Toroids for High-Efficiency DC-DC Converters

    CERN Document Server

    Orlandi, S; Buso, S; Michelis, S; Fuentes, C A; Kayal, M; Faccio, F; Spiazzi, G

    2011-01-01

    The paper describes the design of optimized printed circuit board (PCB) air-core toroids for high-frequency dc-dc converters with strict requirements in terms of volume and noise. The effect of several design parameters on the overall inductor volume, on dc and ac winding resistance, and on the radiated noise will be investigated. PCB toroids are compared to standard air-core solenoids and other state-of-the-art air-core toroids both theoretically and experimentally: at first, using ANSOFT Maxwell and ANSOFT Q3D simulation tools, and subsequently, with laboratory measurements (irradiated noise, efficiency, and frequency response) on several prototypes. These very flexible and rather easy to manufacture inductors appear very attractive for compact high-frequency dc-dc converters where high efficiency, low volume, and low noise are of primary concern.

  20. A Generic Minimal Discrete Model for Toroidal Moments and Its Experimental Realization

    CERN Document Server

    Xiang, Hong; Liu, Liang; Jiang, Tianshu; Zhang, Z Q; Chan, C T; Han, Dezhuan

    2016-01-01

    It is well known that a closed loop of magnetic dipoles can give rise to the rather elusive toroidal moment. However, artificial structures required to generate the necessary magnetic moments are typically optically large, complex to make and easily compromised by the kinetic inductance at high frequencies. Instead of using magnetic dipoles, we propose a minimal model based on just three aligned discrete electric dipoles in which the occurrence of resonant toroidal modes is guaranteed by symmetry. The advantage of this model is its simplicity and the same model supports toroidal moments from the microwave regime up to optical frequencies as exemplified by a three-antenna array and a system consisting of three nano-sized plasmonic particles. Both the microwave and high-frequency configurations exhibit non-radiating "anapoles". Experiments in the microwave regime confirm the theoretical predictions.

  1. Magnetohydrodynamic calculations with a nonmonotonic q profile and equilibrium, sheared toroidal flow

    Energy Technology Data Exchange (ETDEWEB)

    Held, E.D. [Univ. of Wisconsin, Madison, WI (United States). Center for Plasma Theory and Computation; Leboeuf, J.N.; Carreras, B.A. [Oak Ridge National Lab., TN (United States). Fusion Energy Div.

    1998-07-01

    The linear and nonlinear stability of a nonmonotonic q profile is examined using a reduced set of magnetohydrodynamic (MHD) equations with an equilibrium, sheared toroidal flow. The reversed shear profile is shown to be unstable to a rich variety of resistive MHD modes including pressure-driven instabilities and tearing instabilities possessing a tearing/interchange character at low Lundquist number, S, and taking on a double/triple tearing structure at high S. Linear calculations show that the destabilizing effect of toroidal velocity shear on tearing modes is enhanced at finite pressure seen previously for tearing modes at high S. Nonlinear calculations show the generation of a large, m = 1, n = 0, Reynolds-stress-driven poloidal flow in the absence of significant flow damping. Calculations in which the poloidal flow was heavily damped show that sub-Alfvenic, sheared toroidal flows have a minimal effect on weakly-coupled, localized instabilities.

  2. Instability of Non-uniform Toroidal Magnetic Fields in Accretion Disks

    CERN Document Server

    Hirabayashi, Kota

    2016-01-01

    A new type of instability that is expected to drive magnetohydrodynamic (MHD) turbulence from a purely toroidal magnetic field in an accretion disk is presented. It is already known that in a differentially rotating system, the uniform toroidal magnetic field is unstable due to a magnetorotational instability (MRI) under a non-axisymmetric and vertical perturbation, while it is stable under a purely vertical perturbation. Contrary to the previous study, this paper proposes an unstable mode completely confined to the equatorial plane, driven by the expansive nature of the magnetic pressure gradient force under a non-uniform toroidal field. The basic nature of this growing eigenmode, to which we give a name "magneto-gradient driven instability", is studied using linear analysis, and the corresponding nonlinear evolution is then investigated using two-dimensional ideal MHD simulations. Although a single localized magnetic field channel alone cannot provide sufficient Maxwell stress to contribute significantly to...

  3. A toroidal vortex field as an origin of the narrow mass spectrum of neutron stars

    Science.gov (United States)

    Kontorovich, V. M.

    2016-03-01

    The evolution and collapse of a gaseous, self-gravitating sphere in the presence of an internal massive toroidal vortex analogous to the vortex created by the toroidal magnetic field of the Sun is considered. When thermal pressure is taken into account, for sufficiently high masses, the instability is preserved even for a polytropic index γ neutrons differs appreciably. In the ultrarelativistic limit, an interval of stablemasses arises in a neutron gas, between a minimum mass that depends on the circulation velocity in the vortex and the critical mass for the formation of a black hole. This suggests toroidal vortex fields as a possible physical origin for the observed narrow spectrum of neutron-star masses.

  4. Reliability of Arctic offshore installations

    Energy Technology Data Exchange (ETDEWEB)

    Bercha, F.G. [Bercha Group, Calgary, AB (Canada); Gudmestad, O.T. [Stavanger Univ., Stavanger (Norway)]|[Statoil, Stavanger (Norway)]|[Norwegian Univ. of Technology, Stavanger (Norway); Foschi, R. [British Columbia Univ., Vancouver, BC (Canada). Dept. of Civil Engineering; Sliggers, F. [Shell International Exploration and Production, Rijswijk (Netherlands); Nikitina, N. [VNIIG, St. Petersburg (Russian Federation); Nevel, D.

    2006-11-15

    Life threatening and fatal failures of offshore structures can be attributed to a broad range of causes such as fires and explosions, buoyancy losses, and structural overloads. This paper addressed the different severities of failure types, categorized as catastrophic failure, local failure or serviceability failure. Offshore tragedies were also highlighted, namely the failures of P-36, the Ocean Ranger, the Piper Alpha, and the Alexander Kieland which all resulted in losses of human life. P-36 and the Ocean Ranger both failed ultimately due to a loss of buoyancy. The Piper Alpha was destroyed by a natural gas fire, while the Alexander Kieland failed due to fatigue induced structural failure. The mode of failure was described as being the specific way in which a failure occurs from a given cause. Current reliability measures in the context of offshore installations only consider the limited number of causes such as environmental loads. However, it was emphasized that a realistic value of the catastrophic failure probability should consider all credible causes of failure. This paper presented a general method for evaluating all credible causes of failure of an installation. The approach to calculating integrated reliability involves the use of network methods such as fault trees to combine the probabilities of all factors that can cause a catastrophic failure, as well as those which can cause a local failure with the potential to escalate to a catastrophic failure. This paper also proposed a protocol for setting credible reliability targets such as the consideration of life safety targets and escape, evacuation, and rescue (EER) success probabilities. A set of realistic reliability targets for both catastrophic and local failures for representative safety and consequence categories associated with offshore installations was also presented. The reliability targets were expressed as maximum average annual failure probabilities. The method for converting these annual

  5. C-CAP Land Cover, Kauai, Hawaii

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of land derived from high resolution imagery and was analyzed according to the Coastal Change Analysis Program (C-CAP) protocol to determine...

  6. C-CAP Land Cover, Maui, Hawaii

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of land derived from high resolution imagery and was analyzed according to the Coastal Change Analysis Program (C-CAP) protocol to determine...

  7. C-CAP Land Cover, Molokai, Hawaii

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of land derived from high resolution imagery and was analyzed according to the Coastal Change Analysis Program (C-CAP) protocol to determine...

  8. C-CAP Land Cover, Lanai, Hawaii

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of land derived from high resolution imagery and was analyzed according to the Coastal Change Analysis Program (C-CAP) protocol to determine...

  9. Circumpolar Active-Layer Permafrost System (CAPS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Circumpolar Active-Layer Permafrost System (CAPS) contains over 100 data sets pertaining to permafrost and frozen ground topics. It also contains detailed...

  10. C-CAP Hawaii 2005 Land Cover

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of land derived from high resolution imagery and was analyzed according to the Coastal Change Analysis Program (C-CAP) protocol to determine...

  11. Cryopyrin-Associated Autoinflammatory Syndromes (CAPS) - Juvenile

    Science.gov (United States)

    ... of the nervous system, including headaches and deafness. CAPS are not contagious. Treatments that block interleukin-1, an important molecule involved in the inflammatory process, are very effective. To prevent permanent damage, treatment ...

  12. C-CAP Land Cover, Niihau, Hawaii

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of land derived from high resolution imagery and was analyzed according to the Coastal Change Analysis Program (C-CAP) protocol to determine...

  13. C-CAP Niihau 2005 Land Cover

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of land cover derived from high resolution imagery according to the Coastal Change Analysis Program (C-CAP) protocol. This data set utilized 1...

  14. Magnet Test Setup of the CMS Tracker ready for installation

    CERN Multimedia

    Maximilien Brice

    2006-01-01

    The pieces of the Tracker that will be operated in the forthcoming Magnet Test and Cosmic Challenge (MTCC) have been transported inside the dummy tracker support tube to the CMS experimental hall (Point 5, Cessy). The operation took place during the night of 12th May, covering the ~15km distance in about three hours. The transport was monitored for shocks, temperature and humidity with the help of the CERN TS-IC section. The Tracker setup comprises segments of the Tracker Inner Barrel (TIB), the Tracker Outer Barrel (TOB) and Tracker EndCaps (TEC) detectors. It represents roughly 1% of the final CMS Tracker. Installation into the solenoid is foreseen to take place on Wednesday 17th May.

  15. Righting an ATLAS end-cap

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    Each component of the giant ATLAS detector must be moved and transported with great caution so that delicate components are not damaged. Therefore, tests are performed, like the one shown. The end-cap weighs 160 tonnes, making the delicate moving process a non-trivial feat. A special crane and supports have been designed so that the end-cap can be raised using a pivot.

  16. Design and implementation of the CAPS receiver

    Science.gov (United States)

    Hu, Yonghui; Hua, Yu; Hou, Lei; Wei, Jingfa; Wu, Jianfeng

    2009-03-01

    In this paper, based on analyses of the Chinese Area Positioning System (CAPS) satellite (GEO satellite) resources and signal properties, the signal power at the port of the receiver antenna is estimated, and the implementation projects are presented for a switching band C to band L CAPS C/A code receiver integrated with GPS receiver suite and for a CAPS dual frequency P code receiver. A microstrip receiving antenna is designed with high sensitivity and wide beam orientation, the RF front end of the C/A code and P code receivers, and a processor is designed for the navigation baseband. A single frequency CAPS C/A code receiver and a CAPS dual frequency P code receiver are built at the same time. A software process flow is provided, and research on relatively key techniques is also conducted, such as signal searching, code loop and carrier loop algorithms, a height assistant algorithm, a dual frequency difference speed measurement technique, a speed measurement technique using a single frequency source with frequency assistance, and a CAPS time correcting algorithm, according to the design frame of the receiver hardware. Research results show that the static plane positioning accuracy of the CAPS C/A code receiver is 20.5-24.6 m, height accuracy is 1.2-12.8 m, speed measurement accuracy is 0.13-0.3 m/s, dynamic plane positioning accuracy is 24.4 m, height accuracy is 3.0 m, and speed measurement accuracy is 0.24 m/s. In the case of C/A code, the timing accuracy is 200 ns, and it is also shown that the positioning accuracy of the CAPS precise code receiver (1 σ) is 5 m from south to north, and 0.8 m from east to west. Finally, research on positioning accuracy is also conducted.

  17. Design and implementation of the CAPS receiver

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this paper, based on analyses of the Chinese Area Positioning System (CAPS) satellite (GEO satellite) resources and signal properties, the signal power at the port of the receiver antenna is estimated, and the implementation projects are presented for a switching band C to band L CAPS C/A code receiver integrated with GPS receiver suite and for a CAPS dual frequency P code receiver. A microstrip receiving antenna is designed with high sensitivity and wide beam orientation, the RF front end of the C/A code and P code receivers, and a processor is designed for the navigation baseband. A single frequency CAPS C/A code receiver and a CAPS dual frequency P code receiver are built at the same time. A software process flow is provided, and research on relatively key techniques is also conducted, such as signal searching, code loop and carrier loop algorithms, a height assistant algorithm, a dual frequency difference speed measurement technique, a speed measurement technique using a single frequency source with frequency assistance, and a CAPS time correcting algorithm, according to the design frame of the receiver hardware. Research results show that the static plane positioning accuracy of the CAPS C/A code receiver is 20.5-24.6 m, height accuracy is 1.2-12.8 m, speed measurement accuracy is 0.13-0.3 m/s, dynamic plane positioning accuracy is 24.4 m, height accuracy is 3.0 m, and speed measurement accuracy is 0.24 m/s. In the case of C/A code, the timing accuracy is 200 ns, and it is also shown that the positioning accuracy of the CAPS precise code receiver (1σ ) is 5 m from south to north, and 0.8 m from east to west. Finally, research on positioning accuracy is also conducted.

  18. Bifurcation to 3D Helical Magnetic Equilibrium in an Axisymmetric Toroidal Device

    Science.gov (United States)

    Bergerson, W. F.; Auriemma, F.; Chapman, B. E.; Ding, W. X.; Zanca, P.; Brower, D. L.; Innocente, P.; Lin, L.; Lorenzini, R.; Martines, E.; Momo, B.; Sarff, J. S.; Terranova, D.

    2011-12-01

    We report the first direct measurement of the internal magnetic field structure associated with a 3D helical equilibrium generated spontaneously in the core of an axisymmetric toroidal plasma containment device. Magnetohydrodynamic equilibrium bifurcation occurs in a reversed-field pinch when the innermost resonant magnetic perturbation grows to a large amplitude, reaching up to 8% of the mean field strength. Magnetic topology evolution is determined by measuring the Faraday effect, revealing that, as the perturbation grows, toroidal symmetry is broken and a helical equilibrium is established.

  19. Nondiffusive toroidal-momentum-transport in the JFT-2M tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Ida, Katsumi; Itoh, Kimitaka [National Inst. for Fusion Science, Toki, Gifu (Japan); Miura, Yukitoshi; Itoh, Sanae; Matsuda, Toshiaki

    1998-12-01

    A nondiffusive term in the toroidal-momentum-transport equation is evaluated by the analysis of the transport of toroidal rotation in the transient phase, where the direction of neutral beam injection is changed from parallel to the plasma current to antiparallel. The ratio of nondiffusive viscosity coefficient to diffusive viscosity coefficient is evaluated to be 0.1 to 0.3, which increases as the plasma current is decreased. Nondiffusive momentum transport is found to be in proportion to {nabla}T{sub i}. (author)

  20. Bifurcation to 3D helical magnetic equilibrium in an axisymmetric toroidal device.

    Science.gov (United States)

    Bergerson, W F; Auriemma, F; Chapman, B E; Ding, W X; Zanca, P; Brower, D L; Innocente, P; Lin, L; Lorenzini, R; Martines, E; Momo, B; Sarff, J S; Terranova, D

    2011-12-16

    We report the first direct measurement of the internal magnetic field structure associated with a 3D helical equilibrium generated spontaneously in the core of an axisymmetric toroidal plasma containment device. Magnetohydrodynamic equilibrium bifurcation occurs in a reversed-field pinch when the innermost resonant magnetic perturbation grows to a large amplitude, reaching up to 8% of the mean field strength. Magnetic topology evolution is determined by measuring the Faraday effect, revealing that, as the perturbation grows, toroidal symmetry is broken and a helical equilibrium is established.

  1. Entropy of quantum field in toroidal black hole without brick wall

    Institute of Scientific and Technical Information of China (English)

    Wang Bo-Bo

    2008-01-01

    In this paper the entropy of a toroidal black hole due to a scalar field is investigated by using the DLM scheme.The entropy is renormalized to the standard Bekenstein-Hawking formula with a one-loop correction arising from the higher curvature terms of the gravitational action. For the scalar field,the renormalized Newton constant and two renormalized coupling constants in the toroidal black hole are the same as those in the Reissner-Nordstrom black hole except for other one.

  2. Design and Comparison of a 1 MW / 5s HTS SMES with Toroidal and Solenoidal Geometry

    CERN Document Server

    Morandi, Antonio; Gholizad, Babak; Grilli, Francesco; Sirois, Frédéric; Zermeño, Víctor M R

    2015-01-01

    The design of a HTS SMES coil with solenoidal and toroidal geometry is carried out based on a commercially available 2G HTS conductor. A SMES system of practical interest (1 MW / 5 s) is considered. The comparison between ideal toroidal and solenoidal geometry is first discussed and the criteria used for choosing the geometrical parameters of the coils' bore are explained. The design of the real coil is then carried out and the final amount of conductor needed is compared. A preliminary comparison of the two coils in terms of AC loss during one charge discharge cycle is also discussed.

  3. On the possibility of controlling the hydrophilic/hydrophobic characteristics of toroid Mo138 nanocluster polyoxometalates

    Science.gov (United States)

    Grzhegorzhevskii, K. V.; Adamova, L. V.; Eremina, E. V.; Ostroushko, A. A.

    2017-03-01

    The possibility of changing the hydrophilic (polar) surfaces of toroid nanocluster polyoxomolibdates to hydrophobic (nonpolar) surfaces via the modification of Mo138 nanoclusters by surfactant molecules (dodecylpyridinium chloride) as a result of the interaction between these compounds in solutions is demonstrated. Benzene and methanol are used as molecular probes (indicators of the condition of nanocluster surfaces). Comparative characteristics of the equilibrium sorption of benzene and methanol vapors on the initial and modified surfaces of the solid polyoxometalate, and data on the sorption of organic molecules on the surfaces of Rhodamine B-modified nanoclusters of the toroid (Mo138) and keplerate (Mo132) types are obtained.

  4. Evaluation of a relativistic electron ring system as a plasma target for buildup of compact-toroid configurations

    Energy Technology Data Exchange (ETDEWEB)

    Condit, W.C.

    1980-06-26

    A review of the idea of using plasma-loaded electron rings as buildup targets for future compact-toroid machines is presented. Present experiments at Cornell University and Nagoya University are analyzed, and the need for auxiliary heating to reach interesting temperatures is described. Consideration of the effect of two-stream instability, toroidal field, and plasma containment are discussed.

  5. Toroidal-Core Microinductors Biased by Permanent Magnets

    Science.gov (United States)

    Lieneweg, Udo; Blaes, Brent

    2003-01-01

    The designs of microscopic toroidal-core inductors in integrated circuits of DC-to-DC voltage converters would be modified, according to a proposal, by filling the gaps in the cores with permanent magnets that would apply bias fluxes (see figure). The magnitudes and polarities of the bias fluxes would be tailored to counteract the DC fluxes generated by the DC components of the currents in the inductor windings, such that it would be possible to either reduce the sizes of the cores or increase the AC components of the currents in the cores without incurring adverse effects. Reducing the sizes of the cores could save significant amounts of space on integrated circuits because relative to other integrated-circuit components, microinductors occupy large areas - of the order of a square millimeter each. An important consideration in the design of such an inductor is preventing magnetic saturation of the core at current levels up to the maximum anticipated operating current. The requirement to prevent saturation, as well as other requirements and constraints upon the design of the core are expressed by several equations based on the traditional magnetic-circuit approximation. The equations involve the core and gap dimensions and the magnetic-property parameters of the core and magnet materials. The equations show that, other things remaining equal, as the maximum current is increased, one must increase the size of the core to prevent the flux density from rising to the saturation level. By using a permanent bias flux to oppose the flux generated by the DC component of the current, one would reduce the net DC component of flux in the core, making it possible to reduce the core size needed to prevent the total flux density (sum of DC and AC components) from rising to the saturation level. Alternatively, one could take advantage of the reduction of the net DC component of flux by increasing the allowable AC component of flux and the corresponding AC component of current

  6. 42 CFR 418.309 - Hospice cap amount.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Hospice cap amount. 418.309 Section 418.309 Public...) MEDICARE PROGRAM HOSPICE CARE Payment for Hospice Care § 418.309 Hospice cap amount. The hospice cap amount... until October 31 of the following year. (b) Each hospice's cap amount is calculated by the...

  7. Installation package for a solar heating system

    Science.gov (United States)

    1978-01-01

    Installation information is given for a solar heating system installed in Concho Indian School at El Reno, Oklahoma. This package includes a system Operation and Maintenance Manual, hardware brochures, schematics, system operating modes and drawings.

  8. Helium transfer line installation details.

    CERN Multimedia

    G. Perinic

    2007-01-01

    A particularity of the 32 m long four in one helium transfer line in between the cold box in USC55 and the cavern UX5 is the fact that the transfer line passes through a hole in the crane rail support beam. In order to ensure the alignment of the suspension rail in the interconnecting tunnel with the hole in the rail support as well as the connection points at both ends required precise measurements of the given geometries as well as the installation of a temporary target for the verification of the theoretical predictions.

  9. Automated solar collector installation design

    Energy Technology Data Exchange (ETDEWEB)

    Wayne, Gary; Frumkin, Alexander; Zaydman, Michael; Lehman, Scott; Brenner, Jules

    2014-08-26

    Embodiments may include systems and methods to create and edit a representation of a worksite, to create various data objects, to classify such objects as various types of pre-defined "features" with attendant properties and layout constraints. As part of or in addition to classification, an embodiment may include systems and methods to create, associate, and edit intrinsic and extrinsic properties to these objects. A design engine may apply of design rules to the features described above to generate one or more solar collectors installation design alternatives, including generation of on-screen and/or paper representations of the physical layout or arrangement of the one or more design alternatives.

  10. 75 FR 49527 - Caps Visual Communications, LLC; Black Dot Group; Formerly Known as Caps Group Acquisition, LLC...

    Science.gov (United States)

    2010-08-13

    ... Employment and Training Administration Caps Visual Communications, LLC; Black Dot Group; Formerly Known as... Adjustment Assistance on June 24, 2010, applicable to workers of Caps Visual Communications, LLC, Black Dot..., Caps Visual Communications, LLC, Black Dot Group, formerly known as Caps Group Acquisition,...

  11. Displacement pile installation effects in sand

    NARCIS (Netherlands)

    Beijer-Lundberg, A.

    2015-01-01

    Installation effects govern the post-installation behaviour of displacement piles in sand. These effects are currently not completely understood. Suitable experimental techniques to model these installation effects include field, laboratory and experimental models. In the current thesis a small-scal

  12. Dynamics of flatter wind pump installation

    Directory of Open Access Journals (Sweden)

    А. С. Крижановський

    1999-05-01

    Full Text Available Wind pump installation is considered, in which as quality wind engine is used flatter wind engine with vertically located wing blade. For research of dynamics of installation its mathematical model is constructed. Determined is the law of movement of wing blade at a connected load and main characteristics of wind pump installation

  13. Scenarios for a cap beyond 2013; Implications for EU27 agriculture and the cap budget

    NARCIS (Netherlands)

    Helming, J.F.M.; Terluin, I.J.

    2011-01-01

    An ex ante analysis of a set of five policy components (proposed post 2013 CAP measures) has been carried out for the 2014-2020 period, based on the EC Communication The CAP towards 2020 of 18 November 2010. The policy components are defined in such a way that they focus on the contribution of farme

  14. Storage of cellular 5' mRNA caps in P bodies for viral cap-snatching.

    Science.gov (United States)

    Mir, M A; Duran, W A; Hjelle, B L; Ye, C; Panganiban, A T

    2008-12-09

    The minus strand and ambisense segmented RNA viruses include multiple important human pathogens and are divided into three families, the Orthomyxoviridae, the Bunyaviridae, and the Arenaviridae. These viruses all initiate viral transcription through the process of "cap-snatching," which involves the acquisition of capped 5' oligonucleotides from cellular mRNA. Hantaviruses are emerging pathogenic viruses of the Bunyaviridae family that replicate in the cytoplasm of infected cells. Cellular mRNAs can be actively translated in polysomes or physically sequestered in cytoplasmic processing bodies (P bodies) where they are degraded or stored for subsequent translation. Here we show that the hantavirus nucleocapsid protein binds with high affinity to the 5' cap of cellular mRNAs, protecting the 5' cap from degradation. We also show that the hantavirus nucleocapsid protein accumulates in P bodies, where it sequesters protected 5' caps. P bodies then serve as a pool of primers during the initiation of viral mRNA synthesis by the viral polymerase. We propose that minus strand segmented viruses replicating in the cytoplasm have co-opted the normal degradation machinery of P bodies for storage of cellular caps. Our data also indicate that modification of the cap-snatching model is warranted to include a role for the nucleocapsid protein in cap acquisition and storage.

  15. Neoclassical toroidal plasma viscosity with effects of finite banana width for finite aspect ratio tokamaks

    Science.gov (United States)

    Shaing, K. C.; Sabbagh, S. A.

    2016-07-01

    Theory for neoclassical toroidal plasma viscosity has been developed to model transport phenomena, especially, toroidal plasma rotation for tokamaks with broken symmetry. Theoretical predictions are in agreement with the results of the numerical codes in the large aspect ratio limit. The theory has since been extended to include effects of finite aspect ratio and finite plasma β. Here, β is the ratio of the plasma thermal pressure to the magnetic field pressure. However, there are cases where the radial wavelength of the self-consistent perturbed magnetic field strength B on the perturbed magnetic surface is comparable to the width of the trapped particles, i.e., bananas. To accommodate those cases, the theory for neoclassical toroidal plasma viscosity is further extended here to include the effects of the finite banana width. The extended theory is developed using the orbit averaged drift kinetic equation in the low collisionality regimes. The results of the theory can now be used to model plasma transport, including toroidal plasma rotation, in real finite aspect ratio, and finite plasma β tokamaks with the radial wavelength of the perturbed symmetry breaking magnetic field strength comparable to or longer than the banana width.

  16. Optimizing dc-resistance of a foil wounded toroidal inductor combining matlab and comsol

    DEFF Research Database (Denmark)

    Schneider, Henrik; Andersen, Thomas; Knott, Arnold

    2013-01-01

    An optimization routine is presented to optimize the shape of a foil winding of a toroid inductor in terms of the DC resistance. MATLAB was used to define the geometry of the foil winding and COMSOL was used to import the geometry and create a 3D finite element model. The initial parameters...

  17. The effect of toroidal plasma rotation on low-frequency reversed shear Alfven eigenmodes in tokamaks

    NARCIS (Netherlands)

    Haverkort, J. W.

    2012-01-01

    The influence of toroidal plasma rotation on the existence of reversed shear Alfven eigenmodes (RSAEs) near their minimum frequency is investigated analytically. An existence condition is derived showing that a radially decreasing kinetic energy density is unfavourable for the existence of RSAEs. Th

  18. Investigation of a Hybrid Winding Concept for Toroidal Inductors using 3D Finite Element Modeling

    DEFF Research Database (Denmark)

    Schneider, Henrik; Andersen, Thomas; Mønster, Jakob Døllner;

    2013-01-01

    This paper investigates a hybrid winding concept for a toroidal inductor by simulating the winding resistance as a function of frequency. The problem of predicting the resistance of a non-uniform and complex winding shape is solved using 3D Finite Element Modeling. A prototype is built and tested...

  19. Performance assessment and optimization of the ITER toroidal field coil joints

    NARCIS (Netherlands)

    Rolando, G.; Foussat, A.; Knaster, J.; Illiin, Y.; Nijhuis, A.

    2013-01-01

    The ITER toroidal field (TF) system features eighteen coils that will provide the magnetic field necessary to confine the plasma. Each winding pack is composed of seven double pancakes (DP) connected through praying hands joints. Shaking hands joints are used to interface the terminals of the conduc

  20. Internal Field of Homogeneously Magnetized Toroid Sensor for Proton Free Precession Magnetometer

    DEFF Research Database (Denmark)

    Primdahl, Fritz; Merayo, José M.G.; Brauer, Peter

    2005-01-01

    The shift of the NMR spectral line frequency in a proton free precession absolute scalar magnetometer using the omni-directional toroid container for a proton-rich liquid depends on the magnetic susceptibility of the liquid and on the direction of the external field relative to the axis of the to......The shift of the NMR spectral line frequency in a proton free precession absolute scalar magnetometer using the omni-directional toroid container for a proton-rich liquid depends on the magnetic susceptibility of the liquid and on the direction of the external field relative to the axis...... of the toroid. The theoretical shift is estimated for water by computing the additional magnetic field from the magnetization of the liquid and comparing it to the theoretical field in a spherical container. Along the axis the estimated average shift is -0.08 nT and perpendicular to the axis the shift is +0.......08 nT relative to that of a spherical sensor. The field inhomogeneity introduced by the toroid shape amounts to 0.32 nT over the volume of the sensor and is not expected to significantly affect the signal decay time, when considering the typical water line width of about 2.5 InT....

  1. Generation of rotational flows in toroidally confined visco-resistive magnetohydrodynamics

    Science.gov (United States)

    Morales, Jorge; Bos, Wouter; Schneider, Kai; Montgomery, David

    2015-11-01

    We investigate by numerical simulation the generation of rotational flows in a toroid confining a conducting magnetofluid. A current is driven by the application of externally supported electric and magnetic fields. We show how the properties and intensity of the rotations are regulated by dimensionless numbers (Lundquist and viscous Lundquist) that contain the resistivity and viscosity of the magnetofluid. At the magnetohydrodynamic level (uniform mass density and incompressible magnetofluids), rotational flows appear in toroidal, driven MHD. The evolution of these flows with the transport coefficients, geometry, and safety factor are described. Two different toroidal geometries are considered, one with an up-down symmetric and the other with an asymmetric cross section. We show that there exists a fundamental difference between both studied cases: the volume-averaged angular momentum is zero for the symmetric case, while for the asymmetric cross section a finite volume-averaged angular momentum appears. We observe a breaking in the up-down symmetry of the flow and a toroidal preferred direction emerges.

  2. A toroidal trap for the cold $^{87}Rb$ atoms using a rf-dressed quadrupole trap

    CERN Document Server

    Chakraborty, A; Ram, S P; Tiwari, S K; Rawat, H S

    2015-01-01

    We demonstrate the trapping of cold $^{87}Rb$ atoms in a toroidal geometry using a rf-dressed quadrupole magnetic trap formed by superposing a strong radio frequency (rf) field on a quadrupole trap. This rf-dressed quadrupole trap has minimum of the potential away from the quadrupole trap centre on a circular path which facilitates the trapping in the toroidal geometry. In the experiments, the laser cooled atoms were first trapped in the quadrupole trap, then cooled evaporatively using a weak rf-field, and finally trapped in the rf-dressed quadrupole trap. The radius of the toroid could be varied by varying the frequency of the dressing rf-field. It has also been demonstrated that a single rf source and an antenna can be used for the rf-evaporative cooling as well as for rf-dressing of atoms. The atoms trapped in the toroidal trap may have applications in realization of an atom gyroscope as well as in studying the quantum gases in low dimensions.

  3. Toroidal rotation braking with n = 1 magnetic perturbation field on JET

    DEFF Research Database (Denmark)

    Sun, Y; Liang, Y; Koslowski, H R;

    2010-01-01

    A strong toroidal rotation braking has been observed in plasmas with application of an n = 1 magnetic perturbation field on the JET tokamak. Calculation results from the momentum transport analysis show that the torque induced by the n = 1 perturbation field has a global profile. The maximal valu...

  4. A Study on Main Breaker for Quench Protection of HT-7U Toroidal Superconducting Tokamak

    Institute of Scientific and Technical Information of China (English)

    许留伟; 刘小宁

    2002-01-01

    This paper proposes a quench protection project of HT-7U toroidal superconducting tokamak through a forced commutation analysis of DC circuit breaker (DCCB) paralleling fuse.Based on the requirement of quench protection, main parameters are selected. Experimental results demonstrate the validity of this proposed project.

  5. A study on Main Breaker for Quench Protection of HT—7U Toroidal Superconducting Tokammak

    Institute of Scientific and Technical Information of China (English)

    许留伟; 刘小宁

    2002-01-01

    This paper proposes a quench protection project of HT-7U toroidal superconducting tokamak through a forced commutation analysis of DC circuit breaker(DCCB) paralleling fuse.Based on the requirement of quench protection.Amin parameters are selected.Experimental results demonstrate the validity of this proposed project.

  6. Manifestation of the cyclo-toroid nuclear moment in anomalous conversion and Lamb shift

    CERN Document Server

    Tkalya, E V

    2005-01-01

    We offer the hypothesis that atomic nuclei, nucleons, and atoms possess a new type of electromagnetic moment, that we call a ``cyclo-toroid moment''. In nuclei, this moment arises when the toroid dipole (anapole) moments are arrayed in the form of a ring, or, equivalently, when the magnetic moments of the nucleons are arranged in the form of rings which, in turn, constitute the surface of a torus. We establish theoretically that the cyclo-toroid moment plays a role in the processes of the atomic shell--nucleus interaction. The existence of this moment would explain known anomalies in the internal conversion coefficients for $M1$ transitions in nuclei. We show also that the static cyclo-toroid nuclear moment interacts locally inside the nucleus with the vortex part of the atomic electron currents and this leads to an energy shift in atomic $s_{1/2}$ states. For the hydrogen atom the value of this shift may be comparable in order of magnitude to the present accuracy of measurements of the Lamb shift for the $1s...

  7. The Dynamics of an Isolated Plasma Filament at the Edge of a Toroidal Device, Rev. 1

    Energy Technology Data Exchange (ETDEWEB)

    Ryutov, D D

    2006-09-28

    The dynamics of an isolated plasma filament (an isolated blob) in the far scrape-off layer (SOL) of a toroidal device is described, with a proper averaging of the geometrical parameters as well as plasma parameters along the filament. The analysis is limited to the magnetohydrodynamic description. The effects of the anchored ends and finite plasma resistivity are also discussed.

  8. On the fundamental mode of the optical resonator with toroidal mirrors

    Energy Technology Data Exchange (ETDEWEB)

    Serednyakov, S.S.; Vinokurov, N.A. [Budker Institute of Nuclear Physics, Novosibirsk (Russian Federation)

    1995-12-31

    The fundamental mode of the optical resonator with the toroidal mirrors is investigated. The losses in such resonator with the on-axis holes are low in compare with the case of spherical mirrors. The use of this type of optical resonator is briefly discussed.

  9. VIRUS early installation and commissioning

    Science.gov (United States)

    Tuttle, Sarah E.; Hill, Gary J.; Vattiat, Brian L.; Lee, Hanshin; Drory, Niv; Kelz, Andreas; Ramsey, Jason; Peterson, Trent; Noyola, Eva; DePoy, Darren L.; Marshall, Jennifer L.; Chonis, Taylor S.; Dalton, Gavin; Fabricius, Maximilian; Farrow, Daniel; Good, John M.; Haynes, Dionne M.; Indahl, Briana; Jahn, Thomas; Kriel, Hermanus; Nicklas, Harald; Montesano, Francesco; Prochaska, Travis; Allen, Richard D.; Landriau, Martin; MacQueen, Phillip J.; Roth, Martin M.; Savage, Richard; Snigula, Jan M.

    2016-08-01

    VIRUS is a massively replicated spectrograph built for HETDEX, the Hobby Eberly Telescope Dark Energy Experiment. It consists of 156 channels within 78 units fed by 34944 fibers over the 22 arcminute field of the upgraded HET. VIRUS covers a relatively narrow bandpass (350-550nm) at low resolution (R 700) to target the emission of Lyman-alpha emitters (LAEs) for HETDEX. VIRUS is a first demonstration of industrial style assembly line replication in optical astronomy. Installation and testing of VIRUS units began in November of 2015. This winter we celebrated the first on sky instrument activity of the upgraded HET, using a VIRUS unit and LRS2-R (the upgraded facility Low Resolution Spectrograph for the HET). Here we describe progress in VIRUS installation and commissioning through June 2016. We include early sky data obtained to characterize spectrograph performance and on sky performance of the newly upgraded HET. As part of the instrumentation for first science light at the HET, the IFU fed spectrographs were used to test a full range of telescope system functionality including the field calibration unit (FCU).We also use placement of strategic IFUs to map the new HET field to the fiber placement, and demonstrate actuation of the dithering mechanism key to HETDEX observations.

  10. The Inner Detector group celebrates the end of installation

    CERN Multimedia

    Leonardo Rossi

    The Inner Detector installation turned out to involve a very delicate sequence of operations which required the enthusiastic commitment of many people for about as long as a gestation period. The whole saga began in late August 2006 with the Barrel ID travelling to the pit on a sunny day. After the Barrel was connected and signed-off, the End Caps, and later the Pixels, found their way to the heart of ATLAS. We then found it appropriate to mark the successful end of the ID installation with an ID-wide social event and we decided to hold a BBQ during the July ID-week. The organization of the BBQ was a bit stressful as the weather was often rainy, not a surprise for the 2007 summer in Geneva! Being cautious, or maybe educated in careful planning, we reserved the Prevessin BBQ place for both the 4th and the 5th of July. We finally - after consulting multiple weather forecast sources - opted for July 5th which had the highest likelihood for a dry evening. This was the case and indeed this was the only dry evenin...

  11. Power supply system for the COMPASS tokamak re-installed at the IPP, Prague

    Energy Technology Data Exchange (ETDEWEB)

    Zajac, Jaromir [Institute of Plasma Physics, v.v.i., Za Slovankou 3, 18200 Prague (Czech Republic)], E-mail: zajac@ipp.cas.cz; Panek, Radomir; Zacek, Frantisek; Vlcek, Jiri; Hron, Martin [Institute of Plasma Physics, v.v.i., Za Slovankou 3, 18200 Prague (Czech Republic); Krivska, Alena [Institute of Plasma Physics, v.v.i., Za Slovankou 3, 18200 Prague (Czech Republic); Czech Technical University of Prague, Telecommunication Engineering Department, Prague (Czech Republic); Hauptmann, Radim; Danek, Michal [CKD Elektrotechnika, a.s., Prague (Czech Republic); Simek, Josef [CKD Nove Energo, a.s., Prague (Czech Republic); Prosek, Jan [CKD Finergis, a.s., Brno (Czech Republic)

    2009-06-15

    The COMPASS-D tokamak, originally operated in UKAEA Culham, UK, is being reinstalled in the Institute of Plasma Physics (IPP), AS CR. COMPASS-D was designed as a flexible tokamak in the 1980s mainly to explore MHD physics. Its operation (with D-shaped vessel) began in UKAEA in 1992. In 2001 COMPASS-D had been mothballed and later offered to the Institute of Plasma Physics (IPP Prague) AS CR. The re-installation of the COMPASS-D tokamak in IPP Prague had started in 2006. Due to the low power available from the local grid, the two flywheel-generators (47 MVA, 45 MJ, 85 Hz, 6.3 kV) are installed as storage of the required energy. Four AC/DC thyristor rectifiers provide the desired current profiles in toroidal and poloidal coil systems. The start-up circuit, which provides a loop voltage necessary for the plasma generation, is based on fully solid-state switchers and two temporarily inserted resistors. This paper describes the design of the new power supply system and shows details of the commissioning procedures and installation. We also present some results of a comprehensive analysis of the circuit operation performed in Matlab Simulink.

  12. Martian north polar cap summer water cycle

    CERN Document Server

    Brown, Adrian J; Becerra, Patricio; Byrne, Shane

    2016-01-01

    A key outstanding question in Martian science is 'are the polar caps gaining or losing mass and what are the implications for past, current and future climate?' To address this question, we use observations from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) of the north polar cap during late summer for multiple Martian years, to monitor the summertime water cycle in order to place quantitative limits on the amount of water ice deposited and sublimed in late summer. We establish here for the first time the summer cycle of water ice absorption band signatures on the north polar cap. We show that in a key region in the interior of the north polar cap, the absorption band depths grow until Ls=120, when they begin to shrink, until they are obscured at the end of summer by the north polar hood. This behavior is transferable over the entire north polar cap, where in late summer regions 'flip' from being net sublimating into net condensation mode. This transition or 'mode flip' happens earlier for ...

  13. Analysis on the positioning precision of CAPS

    Institute of Scientific and Technical Information of China (English)

    JI YuanFa; SUN XiYan

    2009-01-01

    As a newly developed satellite positioning system,the Chinese Area Positioning System (CAPS) Is a typical direct sequence spread spectrum ranging system like GPS.The positioning precision of such navigation signals depends on many factors,including the pseudo-code rate,the signal to noise ratio,the processing methods for tracking loops and so on.This paper describes the CAPS link budget,the solution approach for CAPS positioning,focusing on the autocorrelation function feature of C/A code signals.The CAPS signal measurement precision is studied by the software approach together with theoretical analysis of the range resolution.Because the conventional Delay Lock Loop (DLL) is vulnerable to the impact of noise,a narrow correlator and multiple correlatore as well as the corresponding discrimination methods of phases are proposed,which improves the robustness of DLL and the code-phase resolution of the measurement.The results show that the Improvement of the DLL structure and the discrimination method are the most important way to improve the ranging resolution.Theoretical analysis and experimental results show that a CAPS receiver could reach a 20-m positioning precision by using three satellites with a supported height from an altimeter.

  14. Analysis on the positioning precision of CAPS

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    As a newly developed satellite positioning system, the Chinese Area Positioning System (CAPS) is a typical direct sequence spread spectrum ranging system like GPS. The positioning precision of such navigation signals depends on many factors, including the pseudo-code rate, the signal to noise ratio, the processing methods for tracking loops and so on. This paper describes the CAPS link budget, the solution approach for CAPS positioning, focusing on the autocorrelation function feature of C/A code signals. The CAPS signal measurement precision is studied by the software approach together with theoretical analysis of the range resolution. Because the conventional Delay Lock Loop (DLL) is vul- nerable to the impact of noise, a narrow correlator and multiple correlators as well as the corresponding discrimination methods of phases are proposed, which improves the robustness of DLL and the code-phase resolution of the measurement. The results show that the improvement of the DLL structure and the discrimination method are the most important way to improve the ranging resolution. Theoretical analysis and experimental results show that a CAPS receiver could reach a 20-m positioning precision by using three satellites with a supported height from an altimeter.

  15. Seismic explosion sources on an ice cap

    DEFF Research Database (Denmark)

    Shulgin, Alexey; Thybo, Hans

    2015-01-01

    Controlled source seismic investigation of crustal structure below ice covers is an emerging technique. We have recently conducted an explosive refraction/wide-angle reflection seismic experiment on the ice cap in east-central Greenland. The data-quality is high for all shot points and a full...... as a strong ice wave. The ice cap leads to low transmission of energy into the crust such that charges need be larger than in conventional onshore experiments to obtain reliable seismic signals. The strong reflection coefficient at the base of the ice generates strong multiples which may mask for secondary...... phases. This effect may be crucial for acquisition of reflection seismic profiles on ice caps. Our experience shows that it is essential to use optimum depth for the charges and to seal the boreholes carefully....

  16. Development and installation of Picostrain sensors in structural systems

    Science.gov (United States)

    Sener, Joseph C.; Latta, Bernard M.; Ross, Jimmy D.

    2004-07-01

    The concept of the Picostrain sensor technology is based on a standard, commercially available, electrical cable assembly embedded in pavement or structural members. The concept has been developed through the 1990s and patented by the Idaho Transportation Department (ITD) in 2003. The objective of this new technology is to build an inexpensive, easily installed and maintained sensor system for the purposes of vehicle classification (VC), vehicle identification (VI), weigh-in-motion (WIM), and vehicle tracking (VT) applications along with real-time monitoring and evaluation of structural performance under static and dynamic traffic loading. It is intended, in the future, that these sensors will be further developed to replace curently utilized expensive embedded pavement and structural sensors for ultimate improvement of transportation decision-making and planning. This will also help to document the movement of people and goods along with the evironmental, social, economic and financial parameters with an emphasis on tracking movements in social life for security based upon the use of this durable and reliable transducers. Approximately, 400 sensors have been installed on and in the reinforced concrete structural members of the West Park Center River Crossing Bridge (Bridge) and the Micron Engineering Center (MEC) building (Building) at Boise State University (BSU) in Boise, Idaho, USA, since 1998. These sensors were installed: in bridge pile caps, piers, girders and decks; bridge abutment embankments; building footings, columns, beams, floor slabs; and, have been linked to instrument cabinets on site. These sensors installed structures may now be called "smart" structures since they contain a resident sensing system capable of maintaining a constant watch over the integrity of the structure. These sensing systems will be able to evaluate the applied loads, as well as the static and dynamic response of the structure. This paper introduces and describes the new

  17. Martian north polar cap summer water cycle

    Science.gov (United States)

    Brown, Adrian J.; Calvin, Wendy M.; Becerra, Patricio; Byrne, Shane

    2016-10-01

    A key outstanding question in Martian science is "are the polar caps gaining or losing mass and what are the implications for past, current and future climate?" To address this question, we use observations from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) of the north polar cap during late summer for multiple Martian years, to monitor the summertime water cycle in order to place quantitative limits on the amount of water ice deposited and sublimed in late summer. We establish here for the first time the summer cycle of water ice absorption band signatures on the north polar cap. We show that in a key region in the interior of the north polar cap, the absorption band depths grow until Ls = 120, when they begin to shrink, until they are obscured at the end of summer by the north polar hood. This behavior is transferable over the entire north polar cap, where in late summer regions 'flip' from being net sublimating into net condensation mode. This transition or 'mode flip' happens earlier for regions closer to the pole, and later for regions close to the periphery of the cap. The observations and calculations presented herein estimate that on average a water ice layer ∼70 microns thick is deposited during the Ls = 135-164 period. This is far larger than the results of deposition on the south pole during summer, where an average layer 0.6-6 microns deep has been estimated by Brown et al. (2014) Earth Planet. Sci. Lett., 406, 102-109.

  18. Assembling the CMS yoke end-caps

    CERN Multimedia

    Laurent Guiraud

    2001-01-01

    A crane is used to piece together one of the end-caps that will provide the path for magnetic flux return on the CMS experiment. A total of six end-cap discs will be assembled before being positioned on the barrel yoke to complete the huge 12 500 tonne cylinder yoke. The magnetic field produced will be greater than any other solenoid created to date at 4 T, 100 000 times greater than the Earth's natural magnetic field, and will store enough energy to melt 18 tonnes of gold.

  19. Pharmacy benefit caps and the chronically ill.

    Science.gov (United States)

    Joyce, Geoffrey F; Goldman, Dana P; Karaca-Mandic, Pinar; Zheng, Yuhui

    2007-01-01

    In this paper we examine medication use among retirees with employer-sponsored drug coverage both with and without annual benefit limits. We find that pharmacy benefit caps are associated with higher rates of medication discontinuation across the most common therapeutic classes and that only a minority of those who discontinue use reinitiate therapy once coverage resumes. Plan members who reach their cap are more likely than others to switch plans and increase their rate of generic use; however, in most cases, the shift is temporary. Given the similarities between these plans and Part D, we make some inferences about reforms for Medicare.

  20. Design and implementation of the CAPS receiver

    Institute of Scientific and Technical Information of China (English)

    HU YongHui; HUA Yu; HOU Lei; WEI JingFa; WU JianFeng

    2009-01-01

    In this paper,baaed on analyses of the Chinese Area Positioning System (CAPS) satellite (GEO satellite) resources and signal properties,the signal power at the port of the receiver antenna is estimated,and the implementation projects are presented for a switching band C to band L CAPS C/A code receiver integrated with GPS receiver suite and for a CAPS dual frequency P code receiver.A microstrip receiving antenna is designed with high sensitivity and wide beam orientation,the RF front end of the C/A code and P code receivers,and a processor is designed for the navigation baseband.A single frequency CAPS C/A code receiver and a CAPS dual frequency P code receiver are built at the same time.A software process flow is provided,and research on relatively key techniques is also conducted,such as signal searching,code loop and carrier loop algorithms,a height assistant algorithm,a dual frequency difference speed measurement technique,a speed measurement technique using a single frequency source with frequency assistance,and a CAPS time correcting algorithm,according to the design frame of the receiver hardware.Research results show that the static plane positioning accuracy of the CAPS C/A code receiver is 20.5-24.6 m,height accuracy is 1.2-12.8 m,speed measurement accuracy is 0.13-0.3 m/s,dynamic plane positioning accuracy is 24.4 m,height accuracy is 3.0 m,and speed measurement accuracy is 0.24 m/s.In the case of C/A code,the timing accuracy is 200 ha,and it is also shown that the positioning accuracy of the CAPS precise code receiver (1σ) is 5 m from south to north,and 0.8 m from east to west.Finally,research on positioning accuracy is also conducted.

  1. Global stability of plasmas with helical boundary deformation and net toroidal current against n=1,2 external modes

    Energy Technology Data Exchange (ETDEWEB)

    Ardela, A.; Cooper, W.A. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)

    1996-09-01

    In this paper we resume a numerical study of the global stability of plasma with helical boundary deformation and non null net toroidal current. The aim was to see whether external modes with n=1,2 (n toroidal mode number) can be stabilized at values of {beta} inaccessible to the tokamak. L=2,3 configurations with several aspect ratios and different numbers of equilibrium field periods are considered. A large variety of toroidal current densities and different pressure profiles are taken into account. Mercier stability is also investigated. (author) 4 figs., 6 refs.

  2. Comparative environmental assessment of unconventional power installations

    Science.gov (United States)

    Sosnina, E. N.; Masleeva, O. V.; Kryukov, E. V.

    2015-08-01

    Procedure of the strategic environmental assessment of the power installations operating on the basis of renewable energy sources (RES) was developed and described. This procedure takes into account not only the operational process of the power installation but also the whole life cycles: from the production and distribution of power resources for manufacturing of the power installations to the process of their recovery. Such an approach gives an opportunity to make a more comprehensive assessment of the influence of the power installations on environments and may be used during adaptation of the current regulations and development of new regulations for application of different types of unconventional power installations with due account of the ecological factor. Application of the procedure of the integrated environmental assessment in the context of mini-HPP (Hydro Power Plant); wind, solar, and biogas power installations; and traditional power installation operating natural gas was considered. Comparison of environmental influence revealed advantages of new energy technologies compared to traditional ones. It is shown that solar energy installations hardly pollute the environment during operation, but the negative influence of the mining operations and manufacturing and utilization of the materials used for solar modules is maximum. Biogas power installations are on the second place as concerns the impact on the environment due to the considerable mass of the biogas installation and gas reciprocating engine. The minimum impact on the environment is exerted by the mini-HPP. Consumption of material and energy resources for the production of the traditional power installation is less compared to power installations on RES; however, this factor incomparably increases when taking into account the fuel extraction and transfer. The greatest impact on the environment is exerted by the operational process of the traditional power installations.

  3. SNP2CAPS: a SNP and INDEL analysis tool for CAPS marker development

    OpenAIRE

    Thiel, Thomas; Kota, Raja; Grosse, Ivo; Stein, Nils; Graner, Andreas

    2004-01-01

    With the influx of various SNP genotyping assays in recent years, there has been a need for an assay that is robust, yet cost effective, and could be performed using standard gel-based procedures. In this context, CAPS markers have been shown to meet these criteria. However, converting SNPs to CAPS markers can be a difficult process if done manually. In order to address this problem, we describe a computer program, SNP2CAPS, that facilitates the computational conversion of SNP markers into CA...

  4. Active toroidal field ripple compensation and MHD feedback control coils in FAST

    Energy Technology Data Exchange (ETDEWEB)

    Ramogida, G., E-mail: giuseppe.ramogida@enea.it [Associazione Euratom-ENEA sulla Fusione, ENEA – C.R. Frascati, Via E. Fermi 45, I-00044 Frascati, RM (Italy); Calabrò, G.; Cocilovo, V.; Crescenzi, F.; Crisanti, F.; Cucchiaro, A. [Associazione Euratom-ENEA sulla Fusione, ENEA – C.R. Frascati, Via E. Fermi 45, I-00044 Frascati, RM (Italy); Di Gironimo, G. [Associazione Euratom-ENEA, CREATE – Università di Napoli Federico II, Via Claudio 21, I-80125 Napoli (Italy); Fresa, R. [Università della Basilicata, Via Nazario Sauro 85, I-85100 Potenza (Italy); Fusco, V. [Associazione Euratom-ENEA sulla Fusione, ENEA – C.R. Frascati, Via E. Fermi 45, I-00044 Frascati, RM (Italy); Martin, P. [Associazione Euratom-ENEA, Consorzio RFX, Corso Stati Uniti 4, I-35127, Padova (Italy); Mastrostefano, S. [Associazione Euratom-ENEA, CREATE – DIEI Università di Cassino, Via Di Biasio 43, I-03043 Cassino, FR (Italy); Mozzillo, R. [Associazione Euratom-ENEA, CREATE – Università di Napoli Federico II, Via Claudio 21, I-80125 Napoli (Italy); Nuzzolese, F. [Università della Basilicata, Via Nazario Sauro 85, I-85100 Potenza (Italy); Renno, F. [Associazione Euratom-ENEA, CREATE – Università di Napoli Federico II, Via Claudio 21, I-80125 Napoli (Italy); Rita, C. [Associazione Euratom-ENEA sulla Fusione, ENEA – C.R. Frascati, Via E. Fermi 45, I-00044 Frascati, RM (Italy); Villone, F. [Associazione Euratom-ENEA, CREATE – DIEI Università di Cassino, Via Di Biasio 43, I-03043 Cassino, FR (Italy); Vlad, G. [Associazione Euratom-ENEA sulla Fusione, ENEA – C.R. Frascati, Via E. Fermi 45, I-00044 Frascati, RM (Italy)

    2013-10-15

    Highlights: ► Active Ripple Compensating System (ARCS) consists of 18 off-centre poloidal coils between plasma and Toroidal Field Coils. ► The current in ARCS, adjustable and opposite to that in TFC, reduces the toroidal ripple below 0.2% at any toroidal fields. ► Feedback Active Control System (FACS) consists of two arrays of 9 in-vessel saddle coils fed by an MHD feedback controller. ► FACS allows robust feedback stabilization of low toroidal number MHD modes enabling plasma operations at low safety factor. ► ARCS and FACS are included in the whole FAST model and first engineering assessments show their feasibility and capability. -- Abstract: The Fusion Advanced Study Torus (FAST) has been proposed as a high magnetic field, compact size tokamak providing a flexible integrated environment to study physics and technology issues in ITER and DEMO relevant conditions. FAST has a quite large natural toroidal field ripple (around 1.5%) due to its compactness and to the number of access ports: this ripple must be lowered to an acceptable level to allow safe operations and a good confinement quality. An Active Ripple Compensating System (ARCS) has been designed, based on a set of poloidal coils placed between the plasma chamber and the Toroidal Field Coils (TFCs). These ARCS coils will be fed with adjustable currents, opposite in direction respect to the TFC currents, and will allow lowering the ripple up to zero and beyond. The CAD model of FAST including the ARCS coils has been completed and preliminary electromagnetic and thermal analyses have been carried out. Moreover, a Feedback Active Control System (FACS) composed of two arrays of in-vessel saddle coils has been designed to allow safe high plasma current, low safety factor operation and to mitigate possibly large ELMs effects in FAST. These FACS coils will be fed by a feedback system to control MHD modes: a first engineering assessment of the current requirements has been carried out.

  5. Knowledge Management at Cap Gemini Nederland

    NARCIS (Netherlands)

    M.J. Vlaanderen (Marie Jose)

    1998-01-01

    textabstractThe theme of this paper is knowledge management (KM) at an organization that provides information technology (IT) services. It is based on the results of a KM-survey of the Finance Division of Cap Gemini (CG) conducted during the spring of 1997.

  6. Mapping of p140Cap phosphorylation sites

    DEFF Research Database (Denmark)

    Repetto, Daniele; Aramu, Simona; Boeri Erba, Elisabetta;

    2013-01-01

    Protein phosphorylation tightly regulates specific binding of effector proteins that control many diverse biological functions of cells (e. g. signaling, migration and proliferation). p140Cap is an adaptor protein, specifically expressed in brain, testis and epithelial cells, that undergoes phosp...

  7. The Effectiveness of Caps on Political Lobbying

    NARCIS (Netherlands)

    Matejka, M.; Onderstal, A.M.; De Waegenaere, A.M.B.

    2002-01-01

    In this paper, we analyze a lobby game, modelled as an all-pay auction in which interest groups submit bids in order to obtain a political prize.The bids are restricted to be below a cap imposed by the government.For both an incomplete and a complete information setting we show the following results

  8. CAP Reform and the Doha Development Agenda

    NARCIS (Netherlands)

    van Dijck, P.; Faber, G.

    2004-01-01

    The CAP reforms that the EU accepted in June 2003 will partially decouple direct income payments to farmers from production and make these payments conditional on cross-compliance. The reforms are driven by enlargement of EU membership, budgetary constraints, mounting pressures from diverse animal w

  9. Installation of Shimming Bars for CYCIAE-100

    Institute of Scientific and Technical Information of China (English)

    LV; Yin-long; WANG; Zhen-hui; ZHONG; Jun-qing; LIU; Geng-shou

    2012-01-01

    <正>The 100 MeV high intensity proton cyclotron, CYCIAE-100, is the most critical equipment of the BRIF project at CIAE. The shimming bars are used to get the isochronous magnetic field. In the process of magnetic mapping and shimming, the bars should be repeated the installed and disassembly for about 10 times. Each time the installation precision must be ensured. The bars installation schedule and quality are directly related to the BRIF project progress.

  10. Modern electrical installation for craft students

    CERN Document Server

    Scaddan, Brian

    2013-01-01

    Modern Electrical Installation for Craft Students, Volume 2, Third Edition discusses several topics concerning electrical installations. The book is comprised of eight chapters that deal with craft theory, associated subjects, and electrical industries. Chapter 1 covers inductors and inductance, while Chapter 2 tackles capacitors and capacitance. Chapter 3 deals with inductance and capacitance in installation work. The book also discusses cells, batteries, and transformers. The electrical industries, control and earthing, and testing are also dealt with. The last chapter discusses the basic el

  11. CAPS-1 and CAPS-2 are essential synaptic vesicle priming proteins.

    Science.gov (United States)

    Jockusch, Wolf J; Speidel, Dina; Sigler, Albrecht; Sørensen, Jakob B; Varoqueaux, Frederique; Rhee, Jeong-Seop; Brose, Nils

    2007-11-16

    Before transmitter-filled synaptic vesicles can fuse with the plasma membrane upon stimulation they have to be primed to fusion competence. The regulation of this priming process controls the strength and plasticity of synaptic transmission between neurons, which in turn determines many complex brain functions. We show that CAPS-1 and CAPS-2 are essential components of the synaptic vesicle priming machinery. CAPS-deficient neurons contain no or very few fusion competent synaptic vesicles, which causes a selective impairment of fast phasic transmitter release. Increases in the intracellular Ca(2+) levels can transiently revert this defect. Our findings demonstrate that CAPS proteins generate and maintain a highly fusion competent synaptic vesicle pool that supports phasic Ca(2+) triggered release of transmitters.

  12. Optimization of Performance of Toroidal Ion Trap with Triangular Electrode by Theoretical Simulation%新型三角形电极圆环离子阱的理论模拟研究

    Institute of Scientific and Technical Information of China (English)

    杨海洋; 许崇晟; 岳磊; Mikhail Sudakov; 潘远江; 丁传凡

    2016-01-01

    The toroidal ion trap is an ideal candidate for miniaturized ion trap because it has much higher ion trapping capacity than a standard quadrupole ion trap of equal trapping dimensions. A novel toroidal ion trap mass analyzer with triangular electrode which contained a filament end cap, a detector endcap, an inner ring and an outer ring was reported. After designing and optimizing the electrodes by theoretical simulations, we found that the asymmetric triangle electrodes could reduce the affection from toroidal shape and improve the ion ejection rate and the mass resolution of the ion trap. The best design of the toroidal ion trap with a mass resolution of 1486 at m/z 609 was obtained.%圆环离子阱由于其离子储存能力明显优于相同体积下的三维离子阱,近年来被认为是离子阱小型化发展的另一个重要方向。为进一步优化圆环形离子阱的质谱性能,特别是质量分辨能力,本研究提出了一种由三角形电极构建的新型圆环离子阱,它由两个完全等同的、截面为三角形的圆环电极及两个大小不等的圆筒型电极所组成,离子通过共振激发方式弹出。通过理论模拟和对电极结构的优化,获得了具有非对称性的三角形电极结构,通过改善圆环结构,优化电场分布,提高了离子引出效率和离子阱的质量分辨能力,其中一种最优化结构的圆环离子阱对m/z 609离子的质量分辨率达到1486。

  13. ID Barrel installed in cryostat

    CERN Multimedia

    Apsimon, R.; Romaniouk, A.

    Wednesday 23rd August was a memorable day for the Inner Detector community as they witnessed the transport and installation of the central part of the inner detector (ID-barrel) into the ATLAS detector. Many members of the collaboration gathered to witness this moment at Point 1. After years of design, construction and commissioning, the outer two detectors (TRT and SCT) of the ID barrel were moved from the SR1 cleanroom to the ATLAS cavern. The barrel was moved across the car park from building 2175 to SX1. Although only a journey of about 100 metres, this required weeks of planning and some degree of luck as far as the weather was concerned. Accelerometers were fitted to the barrel to provide real-time monitoring and no values greater than 0.1 g were recorded, fully satisfying the transport specification for this extremely precise and fragile detector. Muriel, despite her fear of heights, bravely volunteered to keep a close eye on the detector. Swapping cranes to cross the entire parking lot, while Mur...

  14. 'Cooling Caps' May Halt Chemo-Linked Hair Loss

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_163580.html 'Cooling Caps' May Halt Chemo-Linked Hair Loss One ... 2017 TUESDAY, Feb. 14, 2017 (HealthDay News) -- Scalp cooling caps can help breast cancer patients save their ...

  15. Facially amphiphilic thiol capped gold and silver nanoparticles

    Indian Academy of Sciences (India)

    Shreedhar Bhata; Uday Maitra

    2008-11-01

    A series of bile acid-derived facially amphiphilic thiols have been used to cap sliver and gold nanoparticles. The self-assembling properties of these steroid-capped nanoparticles have been investigated and reported in this article.

  16. Studies on orange oil methyl ester in diesel engine with hemispherical and toroidal combustion chamber

    Directory of Open Access Journals (Sweden)

    Karthickeyan Viswanathan

    2016-01-01

    Full Text Available An investigation has been made to compare the emission characteristics of 20% orange oil methyl ester and 80% diesel in volumetric basis with Neat diesel in hemispherical combustion chamber and toroidal combustion chamber. Non-edible orange oil is selected and utilized to prepare alternative fuel to be utilized in Diesel engine. The traditional method of transestrification is employed for preparation orange oil methyl ester. The chemical properties of prepared methyl ester were determined using fouriertransform infrared spectroscopy method. Further its fuel properties were found based on American Society for Testing and Materials standards and compared with Neat diesel fuel properties. A compression ignition engine with electrical dynamometer test rig with gas analyzer has been used. It is observed that 1% of NOx and 4% of HC emission reduced in toroidal combustion chamber engine. However, smoke emission is found to be lower in hemispherical combustion chamber engine.

  17. Experimental Phenomena of Improved Ohmic Confinement Induced by Modulated Toroidal Current on the HT-7 Tokamak

    Institute of Scientific and Technical Information of China (English)

    毛剑珊; 罗家融; P.Phillips; 赵君煜; 揭银先; 吴振伟; 胡立群; 李建刚

    2002-01-01

    The phenomena of improved ohmic confinement have been observed during the modulation of the toroidal curranton the Hefei superconducting Tokamak-7 (HT-7). In the experiment, the programming ohmic heating field wasmodulated. A toroidal frequency-modulated current induced by modulated loop voltage was added on the plasmaequilibrium current. The ratio of ac amplitude of the plasma current to the main plasma current is about 12-30%.These improved plasma confinement phenomena include the facts that the average electron density and the centralelectron temperature both increase, the Dα radiation from the edge is reduced, the magnetohydrodynamics isobviously suppressed by oscillating plasma current, eand the global energy confinement time increases by 27-45%o.It is found that the faster the modulation is, the more effective the improved ohmic confinement phase.

  18. Temperature distribution in magnetized neutron star crusts. II. The effect of a strong toroidal component

    CERN Document Server

    Geppert, U; Page, D; Page, Dany

    2005-01-01

    We continue the study of the effects of a strong magnetic field on the temperature distribution in the crust of a magnetized neutron star (NS) and its impact on the observable surface temperature. Extending the approach initiated in Geppert et al.(2004), we consider more complex and, hence, more realistic, magnetic field structures but still restrict ourselves to axisymmetric configurations. We put special emphasis on the heat blanketing effect of a toroidal field component. We show that asymmetric temperature distributions can occur and a crustal field consisting of dipolar poloidal and toroidal components will cause one polar spot to be larger than the opposing one. These two warm regions can be separated by an extended cold equatorial belt. We present an internal magnetic field structure which can explain both the X-ray and optical spectra of the isolated NS RXJ 1856-3754. We investigate the effects of the resulting surface temperature profiles on the observable lightcurve which an isolated thermally emitt...

  19. Demonstration of ultra-high-Q small mode volume toroid microcavities on a chip

    CERN Document Server

    Kippenberg, T J; Vahala, K J

    2004-01-01

    Optical microcavities confine light spatially and temporally and find application in a wide range of fundamental and applied studies. In many areas, the microcavity figure of merit is not only determined by photon lifetime (or the equivalent quality-factor, Q), but also by simultaneous achievement of small mode volume V . Here we demonstrate ultra-high Q-factor small mode volume toroid microcavities on-a-chip, which exhibit a Q/V factor of more than $10^{6}(\\lambda/n)^{-3}$. These values are the highest reported to date for any chip-based microcavity. A corresponding Purcell factor in excess of 200 000 and a cavity finesse of $2.8\\times10^{6}$ is achieved, demonstrating that toroid microcavities are promising candidates for studies of the Purcell effect, cavity QED or biochemical sensing

  20. Demonstration of ultra-high-Q small mode volume toroid microcavities on a chip

    Science.gov (United States)

    Kippenberg, T. J.; Spillane, S. M.; Vahala, K. J.

    2004-12-01

    Optical microcavities confine light spatially and temporally and find application in a wide range of fundamental and applied studies. In many areas, the microcavity figure of merit is not only determined by photon lifetime (or the equivalent quality-factor, Q), but also by simultaneous achievement of small mode volume (V). Here we demonstrate ultra-high Q-factor small mode volume toroid microcavities on-a-chip, which exhibit a Q/V factor of more than 106(λ/n)-3. These values are the highest reported to date for any chip-based microcavity. A corresponding Purcell factor in excess of 200 000 and a cavity finesse of >2.8×106 is achieved, demonstrating that toroid microcavities are promising candidates for studies of the Purcell effect, cavity QED or biochemical sensing.

  1. Physical mechanism determining the radial electric field and its radial structure in a toroidal plasma

    Energy Technology Data Exchange (ETDEWEB)

    Ida, Katsumi; Miura, Yukitoshi; Itoh, Sanae [and others

    1994-10-01

    Radial structures of plasma rotation and radial electric field are experimentally studied in tokamak, heliotron/torsatron and stellarator devices. The perpendicular and parallel viscosities are measured. The parallel viscosity, which is dominant in determining the toroidal velocity in heliotron/torsatron and stellarator devices, is found to be neoclassical. On the other hand, the perpendicular viscosity, which is dominant in dictating the toroidal rotation in tokamaks, is anomalous. Even without external momentum input, both a plasma rotation and a radial electric field exist in tokamaks and heliotrons/torsatrons. The observed profiles of the radial electric field do not agree with the theoretical prediction based on neoclassical transport. This is mainly due to the existence of anomalous perpendicular viscosity. The shear of the radial electric field improves particle and heat transport both in bulk and edge plasma regimes of tokamaks. (author) 95 refs.

  2. A Toroidal Magnetised Iron Neutrino Detector (MIND) for a Neutrino Factory

    CERN Document Server

    Bross, A; Bayes, R; Laing, A; Soler, F J P; Villanueva, A Cervera; Ghosh, T; Cadenas, J J Gómez; Hernández, P; Martín-Albo, J; Burguet-Castell, J

    2013-01-01

    A neutrino factory has unparalleled physics reach for the discovery and measurement of CP violation in the neutrino sector. A far detector for a neutrino factory must have good charge identification with excellent background rejection and a large mass. An elegant solution is to construct a magnetized iron neutrino detector (MIND) along the lines of MINOS, where iron plates provide a toroidal magnetic field and scintillator planes provide 3D space points. In this report, the current status of a simulation of a toroidal MIND for a neutrino factory is discussed in light of the recent measurements of large $\\theta_{13}$. The response and performance using the 10 GeV neutrino factory configuration are presented. It is shown that this setup has equivalent $\\delta_{CP}$ reach to a MIND with a dipole field and is sensitive to the discovery of CP violation over 85% of the values of $\\delta_{CP}$.

  3. Modeling and control of plasma rotation for NSTX using neoclassical toroidal viscosity and neutral beam injection

    Energy Technology Data Exchange (ETDEWEB)

    Goumiri, I. R. [Princeton Univ., NJ (United States). Mechanical and Aerospace Dept.; Rowley, C. W. [Princeton Univ., NJ (United States). Mechanical and Aerospace Dept.; Sabbagh, S. A. [Columbia Univ., New York, NY (United States). Dept. of Applied Physics and Applied Mathematics; Gates, D. A. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Gerhardt, S. P. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Boyer, M. D. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Andre, R. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Kolemen, E. [Princeton Plasma Physics Lab. (PPPL), Princeton, NJ (United States); Taira, K. [Florida State Univ, Dept Mech Engn, Tallahassee, FL USA.

    2016-02-19

    A model-based feedback system is presented to control plasma rotation in a magnetically confined toroidal fusion device, to maintain plasma stability for long-pulse operation. This research uses experimental measurements from the National Spherical Torus Experiment (NSTX) and is aimed at controlling plasma rotation using two different types of actuation: momentum from injected neutral beams and neoclassical toroidal viscosity generated by three-dimensional applied magnetic fields. Based on the data-driven model obtained, a feedback controller is designed, and predictive simulations using the TRANSP plasma transport code show that the controller is able to attain desired plasma rotation profiles given practical constraints on the actuators and the available measurements of rotation.

  4. Measurement of toroidal vessel eddy current during plasma disruption on J-TEXT

    Energy Technology Data Exchange (ETDEWEB)

    Liu, L. J.; Yu, K. X.; Zhang, M., E-mail: zhangming@hust.edu.cn; Zhuang, G.; Li, X.; Yuan, T.; Rao, B.; Zhao, Q. [State Key Laboratory of Advanced Electromagnetic Engineering and Technology, School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2016-01-15

    In this paper, we have employed a thin, printed circuit board eddy current array in order to determine the radial distribution of the azimuthal component of the eddy current density at the surface of a steel plate. The eddy current in the steel plate can be calculated by analytical methods under the simplifying assumptions that the steel plate is infinitely large and the exciting current is of uniform distribution. The measurement on the steel plate shows that this method has high spatial resolution. Then, we extended this methodology to a toroidal geometry with the objective of determining the poloidal distribution of the toroidal component of the eddy current density associated with plasma disruption in a fusion reactor called J-TEXT. The preliminary measured result is consistent with the analysis and calculation results on the J-TEXT vacuum vessel.

  5. MHD equilibrium of toroidal fusion plasma with stationary flows; Rownowaga MHD toroidalnej plazmy termojadrowej z przeplywami

    Energy Technology Data Exchange (ETDEWEB)

    Galkowski, A. [Institute of Atomic Energy, Otwock-Swierk (Poland)

    1994-12-31

    Non-linear ideal MHD equilibria in axisymmetric system with flows are examined, both in 1st and 2nd ellipticity regions. Evidence of the bifurcation of solutions is provided and numerical solutions of several problems in a tokamak geometry are given, exhibiting bifurcation phenomena. Relaxation of plasma in the presence of zero-order flows is studied in a realistic toroidal geometry. The field aligned flow allows equilibria with finite pressure gradient but with homogeneous temperature distribution. Numerical calculations have been performed for the 1st and 2nd ellipticity regimes of the extended Grad-Shafranov-Schlueter equation. Numerical technique, alternative to the well-known Grad`s ADM methods has been proposed to deal with slow adiabatic evolution of toroidal plasma with flows. The equilibrium problem with prescribed adiabatic constraints may be solved by simultaneous calculations of flux surface geometry and original profile functions. (author). 178 refs, 37 figs, 5 tabs.

  6. An integral equation-based numerical solver for Taylor states in toroidal geometries

    CERN Document Server

    O'Neil, Michael

    2016-01-01

    We develop an algorithm for the numerical calculation of Taylor states (also known as Beltrami, or force-free fields) in toroidal and toroidal-shell geometries using an analytical framework developed for the solution to the time-harmonic Maxwell equations. The scheme relies on the generalized Debye source representation of Maxwell fields and an integral representation of Beltrami fields which immediately yields a well-conditioned second-kind integral equation. This integral equation has a unique solution whenever the Beltrami parameter $\\lambda$ is not a member of a discrete, countable set of resonances which physically correspond to spontaneous symmetry breaking in the plasma. Several numerical examples relevant to magnetohydrodynamic equilibria calculations are provided. Lastly, our approach easily generalizes to arbitrary geometries, both bounded and unbounded, and of varying genus.

  7. Magnetic field perturbartions in closed-field-line systems with zero toroidal magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Mauel, M; Ryutov, D; Kesner, J

    2003-12-02

    In some plasma confinement systems (e.g., field-reversed configurations and levitated dipoles) the confinement is provided by a closed-field-line poloidal magnetic field. We consider the influence of the magnetic field perturbations on the structure of the magnetic field in such systems and find that the effect of perturbations is quite different from that in the systems with a substantial toroidal field. In particular, even infinitesimal perturbations can, in principle, lead to large radial excursions of the field lines in FRCs and levitated dipoles. Under such circumstances, particle drifts and particle collisions may give rise to significant neoclassical transport. Introduction of a weak regular toroidal magnetic field reduces radial excursions of the field lines and neoclassical transport.

  8. Tracking formulas and strategies for a receiver oriented dual-axis tracking toroidal heliostat

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Minghuan; Wang, Zhifeng; Liang, Wenfeng; Zhang, Xiliang; Zang, Chuncheng [Key Laboratory of Solar Thermal Energy and Photovoltaic System of Chinese Academy of Sciences, Institute of Electrical Engineering, Beijing 100190 (China); Lu, Zhenwu; Wei, Xiudong [Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences (CAS), Jilin 130033 (China)

    2010-06-15

    A 4 m x 4 m toroidal heliostat with receiver oriented dual-axis tracking, also called spinning-elevation tracking, was developed as an auxiliary heat source for a hydrogen production system. A series of spinning-elevation tracking formulas have been derived for this heliostat. This included basic tracking formulas, a formula for the elevation angle for heliostat with a mirror-pivot offset, and a more general formula for the biased elevation angle. This paper presents the new tracking formulas in detail and analyzes the accuracy of applying a simplifying approximation. The numerical results show these receiver oriented dual-axis tracking formula approximations are accurate to within 2.5 x 10{sup -6} m in image plane. Some practical tracking strategies are discussed briefly. Solar images from the toroidal heliostat at selected times are also presented. (author)

  9. Experimental study of toroidicity-induced Alfven eigenmode (TAE) stability at high q(0)

    Energy Technology Data Exchange (ETDEWEB)

    Batha, S.H.; Levinton, F.M. [Fusion Physics and Technology, Torrance, CA (United States); Spong, D.A. [Oak Ridge National Lab., TN (United States)] [and others

    1995-07-01

    Experiments to destabilize the Toroidicity-induced Alfven Eigenmode (TAE) by energetic alpha particles were performed on the Tokamak Fusion Test Reactor using deuterium and tritium fuel. To decrease the alpha particle pressure instability threshold, discharges with an elevated value of q(0) > 1.5 were used. By raising q(0), the radial location of the low toroidal-mode-number TAE gaps moves toward the magnetic axis and into alignment with the region of maximum alpha pressure gradient, thereby (in theory) lowering the value of {beta}{sub {alpha}}(0) required for instability. No TAE activity was observed when the central alpha particle {beta}{sub {alpha}} reached 0.08% in a discharge with fusion power of 2.4 MW. Calculations show that the fusion power is within a factor of 1.5 to 3 of the instability threshold.

  10. Evaluation of toroidal torque by non-resonant magnetic perturbations in tokamaks for resonant transport regimes using a Hamiltonian approach

    CERN Document Server

    Albert, Christopher G; Kapper, Gernot; Kasilov, Sergei V; Kernbichler, Winfried; Martitsch, Andreas F

    2016-01-01

    Toroidal torque generated by neoclassical viscosity caused by external non-resonant, non-axisymmetric perturbations has a significant influence on toroidal plasma rotation in tokamaks. In this article, a derivation for the expressions of toroidal torque and radial transport in resonant regimes is provided within quasilinear theory in canonical action-angle variables. The proposed approach treats all low-collisional quasilinear resonant NTV regimes including superbanana plateau and drift-orbit resonances in a unified way and allows for magnetic drift in all regimes. It is valid for perturbations on toroidally symmetric flux surfaces of the unperturbed equilibrium without specific assumptions on geometry or aspect ratio. The resulting expressions are shown to match existing analytical results in the large aspect ratio limit. Numerical results from the newly developed code NEO-RT are compared to calculations by the quasilinear version of the code NEO-2 at low collisionalities. The importance of the magnetic shea...

  11. Toroidally Resolved Structure of Divertor Heat Flux in RMP H-mode Discharges on DIII-D

    Energy Technology Data Exchange (ETDEWEB)

    Jakubowski, M. W. [Max-Planck-Institute for Plasmaphysik, EURATOM-Association, Greifswald, Germany; Evans, T.E. [General Atomics, San Diego; Fenstermacher, M. E. [Lawrence Livermore National Laboratory (LLNL); Lasnier, C. J. [Lawrence Livermore National Laboratory (LLNL); Wolf, R. C. [Max-Planck-Institute for Plasmaphysik, EURATOM-Association, Greifswald, Germany; Baylor, Larry R [ORNL; Boedo, J.A. [University of California, San Diego; Burrell, K. H. [General Atomics; DeGrassie, J. S. [General Atomics, San Diego; Gohil, P. [General Atomics; Mordijck, S. [University of California, San Diego; Laengner, R. [Forschungszentrum Julich, Julich, Germany; Leonard, A. W. [General Atomics; Moyer, R.A. [University of California, San Diego; Petrie, T. W. [General Atomics, San Diego; Petty, C C. [General Atomics, San Diego; Pinsker, R. I. [General Atomics, San Diego; Rhodes, T. L. [University of California, Los Angeles; Schaffer, M. J. [General Atomics, San Diego; Schmitz, O. [Forschungszentrum Julich, Julich, Germany; Snyder, P. B. [General Atomics; Stoschus, H. [EURATOM / FZ-Juelich, Germany; Osborne, T. H. [General Atomics; Orlov, D. M. [University of California, San Diego & La Jolla; Unterberg, Ezekial A [ORNL; Watkins, J. G. [Sandia National Laboratories (SNL)

    2011-01-01

    As shown on DIII-D edge localized modes (ELMs) can be either completely eliminated or mitigated with resonant magnetic perturbation (RMP) fields. Two infrared cameras, separated 105 degrees toroidally, were used to make simultaneous measurements of ELM heat loads with high frame rates. Without the RMP fields ELMs display a variety of different heat load dynamics and a range of toroidal variability that is characteristic of their 3D structure. Comparing radial averages there is no asymmetry between two toroidal locations. With RMP-mitigated ELMs, the variability in the radially averaged power loads is significantly reduced and toroidal asymmetries in power loads are introduced. In addition to RMP ELM suppression scenarios an RMP scenario with only very small ELMs and very good confinement has been achieved.

  12. High-throughput beamline for attosecond pulses based on toroidal mirrors with microfocusing capabilities.

    Science.gov (United States)

    Frassetto, F; Trabattoni, A; Anumula, S; Sansone, G; Calegari, F; Nisoli, M; Poletto, L

    2014-10-01

    We have developed a novel attosecond beamline designed for attosecond-pump/attosecond probe experiments. Microfocusing of the Extreme-ultraviolet (XUV) radiation is obtained by using a coma-compensated optical configuration based on the use of three toroidal mirrors controlled by a genetic algorithm. Trains of attosecond pulses are generated with a measured peak intensity of about 3 × 10(11) W/cm(2).

  13. Particle Simulation Code for the Electron Temperature Gradient Instability in Tokamak Toroidal Plasmas

    Institute of Scientific and Technical Information of China (English)

    JIANGuangde; DONGJiaqi

    2003-01-01

    A numerical simulation code has been established with particle simulation method in order to study the gyro-kinetic equations for the electrostatic electron temperature gradient modes in toroidal plasmas. The flowchart is given as well for the code. The fourth-order adaptive step-size scheme is adopted, that saves computer time and is simple. The calculation code is useful for the research of the electron temperature gradient instability.

  14. Topological symmetry breaking of self-interacting fractional Klein-Gordon field theories on toroidal spacetime

    Energy Technology Data Exchange (ETDEWEB)

    Lim, S C [Faculty of Engineering, Multimedia University, Jalan Multimedia, Cyberjaya, 63100, Selangor Darul Ehsan (Malaysia); Teo, L P [Faculty of Information Technology, Multimedia University, Jalan Multimedia, Cyberjaya, 63100, Selangor Darul Ehsan (Malaysia)], E-mail: sclim@mmu.edu.my, E-mail: lpteo@mmu.edu.my

    2008-04-11

    Quartic self-interacting fractional Klein-Gordon scalar massive and massless field theories on toroidal spacetime are studied. The effective potential and topologically generated mass are determined using zeta-function regularization technique. Renormalization of these quantities are derived. Conditions for symmetry breaking are obtained analytically. Simulations are carried out to illustrate regions or values of compactified dimensions where symmetry-breaking mechanisms appear.

  15. Zonal Flow Patterns: How Toroidal Coupling Induces Phase Jumps and Shear Layers

    CERN Document Server

    Guo, Z B

    2016-01-01

    A new, frequency modulation mechanism for zonal flow pattern formation is presented. The model predicts the probability distribution function of the flow strength as well as the evolution of the characteristic spatial scale. Magnetic toroidicity-induced global phase dynamics is shown to determine the spatial structure of the flow. A key result is the observation that global phase patterning can lead to zonal flow formation in the absence of turbulence inhomogeneity.

  16. High-throughput beamline for attosecond pulses based on toroidal mirrors with microfocusing capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Frassetto, F.; Poletto, L., E-mail: poletto@dei.unipd.it [National Research Council, Institute of Photonics and Nanotechnologies, via Trasea 7, 35131 Padova (Italy); Trabattoni, A.; Anumula, S.; Sansone, G. [Department of Physics, Politecnico di Milano, Piazza L. Da Vinci 32, 20133 Milano (Italy); Calegari, F. [National Research Council, Institute of Photonics and Nanotechnologies, Piazza L. da Vinci 32, 20133 Milano (Italy); Nisoli, M. [Department of Physics, Politecnico di Milano, Piazza L. Da Vinci 32, 20133 Milano (Italy); National Research Council, Institute of Photonics and Nanotechnologies, Piazza L. da Vinci 32, 20133 Milano (Italy)

    2014-10-15

    We have developed a novel attosecond beamline designed for attosecond-pump/attosecond probe experiments. Microfocusing of the Extreme-ultraviolet (XUV) radiation is obtained by using a coma-compensated optical configuration based on the use of three toroidal mirrors controlled by a genetic algorithm. Trains of attosecond pulses are generated with a measured peak intensity of about 3 × 10{sup 11} W/cm{sup 2}.

  17. Stability analysis of toroidicity-induced Alfven eigenmodes in TFTR DT experiments

    Energy Technology Data Exchange (ETDEWEB)

    Fu, G.Y.; Cheng, C.Z.; Budny, R.; Chang, Z.; Darrow, D.S.; Fredrickson, E.; Mazzucato, E.; Nazikian, R.; Zweben, S.

    1995-05-15

    The toroidicity-induced Alfvin eigenmodes (TAE) with radially extended structure are found to be stable in the Tokamak Fusion Test Reactor Deuterium-Tritium plasmas. A core localized TAE mode is shown to exist near the center of the plasma at small magnetic shear and finite plasma beta, which can be destabilized by energetic alpha particles on TFTR. With additional instability drive from fast minority ions powered by ICRH, both the global and the core localized TAE modes can be readily destabilized.

  18. New picture of the 1/1 internal kink and sawtooth in compressible toroidal plasmas

    Science.gov (United States)

    Sugiyama, Linda

    2013-10-01

    The m = 1 , n = 1 internal kink mode and the sawtooth crash have been analyzed extensively in magnetically confined toroidal plasmas. Nevertheless, many questions remain. A new analysis, with the aid of numerical simulation, shows that small parameter expansions such as large aspect ratio break down in general for the MHD compressible toroidal 1/1 instability with realistically small growth rates. The perpendicular momentum rate of change ρ ∂v⊥ / ∂ t must be very small compared to the individual terms in - ρ (v . ∇) v |⊥ + J × B |⊥ -∇⊥ p . The lowest order mode still has the standard 1/1 internal kink form, but the v⊥ magnitude and growth rate are determined by the higher order terms. Terms containing B~ϕ , nominally associated with the compressional Alfvén wave are important. One corollary is that reduced MHD (RMHD) fails completely and Sweet-Parker-type reconnection never develops. At a critical nonlinear amplitude, associated with the growth of the higher toroidal harmonics, a fast, explosive crash begins with rapidly accelerating velocity growth that matches observations. Other transverse MHD instabilities experience analogous effects. Work supported by the U.S. Department of Energy.

  19. The turbulent diffusion of toroidal magnetic flux as inferred from properties of the sunspot butterfly diagram

    CERN Document Server

    Cameron, R H

    2016-01-01

    In order to match observed properties of the solar cycle, flux-transport dynamo models require the toroidal magnetic flux to be stored in a region of low magnetic diffusivity, typically located at or below the bottom of the convection zone. We infer the turbulent magnetic diffusivity affecting the toroidal field on the basis of empirical data. We consider the time evolution of mean latitude and width of the activity belts of solar cycles 12--23 and their dependence on cycle strength. We interpret the decline phase of the cycles as a diffusion process. The activity level of a given cycle begins to decline when the centers of its equatorward propagating activity belts come within their width (at half maximum) from the equator. This happens earlier for stronger cycles because their activity belts are wider. From that moment on, the activity and the belt width decrease in the same manner for all cycles, independent of their maximum activity level. In terms of diffusive cancellation of opposite-polarity toroidal f...

  20. Equilibrium poloidal field distributions in reversed-field-pinch toroidal discharges

    Energy Technology Data Exchange (ETDEWEB)

    Baker, D.A.; Mann, L.W.; Schoenberg, K.F.

    1982-04-01

    A comparison between the analytic formulae of Shafranov for equilibrium in axisymmetric toroidal reversed field pinch (RFP) systems and fully toroidal numerical solutions of the Grad-Shafranov equation is presented as a function of poloidal beta, internal plasma inductance, and aspect ratio. The Shafranov formula for the equilibrium poloidal field distribution is accurate to within 5% for aspect ratios greater than 2, poloidal betas less than 50%, and for plasma current channels that exceed one-third of the minor toroidal radius. The analytic description for the center shift of the innermost flux surface that encloses the plasma current (the Shafranov shift) is accurate to within 15% for aspect ratios greater than 2 and poloidal betas below 50%, provided the shift does not exceed one-tenth of the minor conducting boundary radius. The behavior of the magnetic axis shift as a function of plasma parameters is included. The Shafranov formulae provide a convenient method for describing the equilibrium behavior of an RFP discharge. Examples illustrating the application of the analytic formulae to the Los Alamos ZT-40M RFP experiment are given.

  1. Bifurcation physics of magnetic islands and stochasticity explored by heat pulse propagation studies in toroidal plasmas

    Science.gov (United States)

    Ida, K.; Kobayashi, T.; Yoshinuma, M.; Suzuki, Y.; Narushima, Y.; Evans, T. E.; Ohdachi, S.; Tsuchiya, H.; Inagaki, S.; Itoh, K.

    2016-09-01

    Bifurcation physics of a magnetic island was investigated using the heat pulse propagation technique produced by the modulation of electron cyclotron heating. There are two types of bifurcation phenomena observed in a large helical device (LHD) and DIII-D. One is a bifurcation of the magnetic topology between nested and stochastic fields. The nested state is characterized by the bi-directional (inward and outward) propagation of the heat pulse with slow propagation speed. The stochastic state is characterized by the fast propagation of the heat pulse with electron temperature flattening. The other bifurcation is between the magnetic island with larger thermal diffusivity and that with smaller thermal diffusivity. The damping of toroidal flow is observed at the O-point of the magnetic island both in helical plasmas and in tokamak plasmas during a mode locking phase with strong flow shears at the boundary of the magnetic island. Associated with the stochastization of the magnetic field, the abrupt damping of toroidal flow is observed in LHD. The toroidal flow shear shows a linear decay, while the ion temperature gradient shows an exponential decay. This observation suggests that this flow damping is due to the change in the non-diffusive term of momentum transport.

  2. The linear tearing instability in three dimensional, toroidal gyro-kinetic simulations

    Energy Technology Data Exchange (ETDEWEB)

    Hornsby, W. A., E-mail: william.hornsby@ipp.mpg.de; Migliano, P.; Buchholz, R.; Kroenert, L.; Weikl, A.; Peeters, A. G. [Theoretical Physics V, Department of Physics, Universitaet Bayreuth, Bayreuth D-95447 (Germany); Zarzoso, D.; Poli, E. [Max-Planck-Institut für Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching bei München (Germany); Casson, F. J. [CCFE, Culham Science Centre, Abingdon, Oxon OX14 3DB (United Kingdom)

    2015-02-15

    Linear gyro-kinetic simulations of the classical tearing mode in three-dimensional toroidal geometry were performed using the global gyro-kinetic turbulence code, GKW. The results were benchmarked against a cylindrical ideal MHD and analytical theory calculations. The stability, growth rate, and frequency of the mode were investigated by varying the current profile, collisionality, and the pressure gradients. Both collisionless and semi-collisional tearing modes were found with a smooth transition between the two. A residual, finite, rotation frequency of the mode even in the absence of a pressure gradient is observed, which is attributed to toroidal finite Larmor-radius effects. When a pressure gradient is present at low collisionality, the mode rotates at the expected electron diamagnetic frequency. However, the island rotation reverses direction at high collisionality. The growth rate is found to follow a η{sup 1∕7} scaling with collisional resistivity in the semi-collisional regime, closely following the semi-collisional scaling found by Fitzpatrick. The stability of the mode closely follows the stability analysis as performed by Hastie et al. using the same current and safety factor profiles but for cylindrical geometry, however, here a modification due to toroidal coupling and pressure effects is seen.

  3. Twisted toroidal vortex-solitons in inhomogeneous media with repulsive nonlinearity

    CERN Document Server

    Kartashov, Y V; Shnir, Y; Torner, L

    2014-01-01

    Toroidal modes in the form of so-called Hopfions, with two independent winding numbers, a hidden one (twist, s), which characterizes a circular vortex thread embedded into a three-dimensional soliton, and the vorticity around the vertical axis m, appear in many fields, including the field theory, ferromagnetics, and semi- and superconductors. Such topological states are normally generated in multi-component systems, or as trapped quasi-linear modes in toroidal potentials. We uncover that stable solitons with this structure can be created, without any linear potential, in the single-component setting with the strength of repulsive nonlinearity growing fast enough from the center to the periphery, for both steep and smooth modulation profiles. Toroidal modes with s=1 and vorticity m=0,1,2 are produced. They are stable for m1. An approximate analytical solution is obtained for the twisted ring with s=1, m=0. Under the application of an external torque, it rotates like a solid ring. The setting can be implemented...

  4. Three-dimensional neutron source models for toroidal fusion energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Slaybaugh, R.N. [Fusion Technology Institute, University of Wisconsin, 1500 Engineering Dr., Madison, WI 53706 (United States)], E-mail: slaybaugh@wisc.edu; Wilson, P.P.H. [Fusion Technology Institute, University of Wisconsin, 1500 Engineering Dr., Madison, WI 53706 (United States)], E-mail: wilsonp@engr.wisc.edu; El-Guebaly, L.A.; Marriott, E.P. [Fusion Technology Institute, University of Wisconsin, 1500 Engineering Dr., Madison, WI 53706 (United States)

    2009-06-15

    Developments in computer architecture and neutronics code capabilities have enabled high-resolution analysis of complex 3D geometries. Thus, accurately modeling 3D source distributions has become important for nuclear analyses. In this work two methods are described which generate and sample such 3D sources based directly on the plasma parameters of a fusion device and which facilitate the ability to update the neutron source following changes to the plasma physics configuration. The cylindrical mesh method is for toroidally symmetric machines and utilizes data in a standard file format which represents the poloidal magnetic flux on an R-Z grid. The conformal hexahedral mesh method takes plasma physics data generated in an idealized toroidal coordinate system and uses a Jacobian transformation and a functional expansion to generate the source. This work describes each methodology and associated test cases. The cylindrical mesh method was applied to ARIES-RS and the conformal hexahedral mesh method was applied to a uniform torus and ARIES-CS. The results of the test cases indicate that these improved source definitions can have important effects on pertinent engineering parameters, such as neutron wall loading, and should therefore be used for high-resolution nuclear analyses of all toroidal devices.

  5. CMS end-cap yoke at the detector's assembly site.

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    The magnetic flux generated by the superconducting coil in the CMS detector is returned via an iron yoke comprising three end-cap discs at each end (end-cap yoke) and five concentric cylinders (barrel yoke). This picture shows the first of three end-cap discs (red) seen through the outer cylinder of the vacuum tank which will house the superconducting coil.

  6. The Alignment System of the ATLAS Muon End-Cap Spectrometer

    CERN Document Server

    Schricker, Alexander

    2002-01-01

    The Large Hadron Collider at CERN will offer an unparalleled opportunity to probe fundamental physics at an energy scale well beyond that reached by current experiments. The ATLAS detector is being designed to fully exploit the potential of the LHC for revealing new aspects of the fundamental structure of nature. The muon spectrometer itself must measure with a momentum resolution of s10% for muons with a transverse momentum of pT =1TeV, to fully exploit the advantages offered by the open superconducting air core muon toroid magnet system. At this level of momentum resolution the muon spectrometer relies heavily on the ability to master the alignment of the large muon chambers spaced far apart. The overall contribution of the alignment to the total sagitta error must be less than 30 μm r.m.s. In order to meet the stringent alignment requirements the positions of the muon chambers are constantly monitored with optical alignment technologies. The end-caps of this spectrometer are therefore embedded in an align...

  7. 49 CFR 393.30 - Battery installation.

    Science.gov (United States)

    2010-10-01

    ... NECESSARY FOR SAFE OPERATION Lamps, Reflective Devices, and Electrical Wiring § 393.30 Battery installation... 49 Transportation 5 2010-10-01 2010-10-01 false Battery installation. 393.30 Section 393.30 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL MOTOR CARRIER...

  8. Installation Service - Changes in opening hours

    CERN Multimedia

    GS Department

    2010-01-01

    For organizational matters, please note that, as from 15 March 2010, the Installation Service will have wen opening hours. The new schedule will be from 14:00 to 17:00 (Monday to Friday). Contact persons are: Martine Briant, Karine Robert and Claudia Bruggmann. The office address remains 73-3-014. Installation Service

  9. 46 CFR 111.33-5 - Installation.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Installation. 111.33-5 Section 111.33-5 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Power Semiconductor Rectifier Systems § 111.33-5 Installation. Each semiconductor rectifier...

  10. ATLAS semiconductor tracker installed into its barrel

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    The ATLAS silicon tracker is installed in the silicon tracker barrel. Absolute precision was required in this operation to ensure that the tracker was inserted without damage through minimal clearance. The installation was performed in a clean room on the CERN site so that no impurities in the air would contaminate the tracker's systems.

  11. Numerical Simulation of Non-Inductive Startup of the Pegasus Toroidal Experiment

    Science.gov (United States)

    O'Bryan, John B.

    The dynamics and relaxation of magnetic flux ropes produced during non-inductive startup of the Pegasus Toroidal Experiment are simulated with nonlinear magnetohydrodynamic and two-fluid plasma models. A current filament is produced by a single injector and directed along multiple passes by toroidal and vertical vacuum magnetic field components. Adjacent passes of the current filament merge and reconnect, releasing an axisymmetric current ring from the driven channel. Squashing degree analysis indicates the presence of a quasi-separatrix layer (QSL) during ring formation, but the QSL does not solely correspond to magnetic reconnection. Chaotic scattering is also apparent from the distribution of magnetic field-line lengths. The merging of adjacent passes constitutes coherent dynamo action that affects the toroidally-averaged magnetic-field distribution. The MHD dynamo--primarily from the vertical displacement of the current channel--concentrates symmetric poloidal flux and transfers significant energy to the forming flux-rope ring. Accumulation of poloidal flux over many reconnection events contributes to the development of a poloidal magnetic field null near the central column that redirects the driven current filament, such that its path traces a toroidal surface. After cessation of the simulated current drive, temperature and current profiles broaden and closed flux surfaces form rapidly and encompass a large plasma volume. High toroidal-mode number harmonics of the magnetic energy decay preferentially, leaving a tokamak-like plasma suitable for transition to other forms of current drive. Computations with the two-fluid terms in Ohm's Law produce qualitatively similar plasma evolution to the MHD computations. However, for the computations with the two-fluid plasma model, the ion fluid significantly decouples from the electron fluid, weakening the dynamics during magnetic reconnection. This effect is quantified by comparing global and local plasma parameters in

  12. Arduino Tool: For Interactive Artwork Installations

    CERN Document Server

    Shaikh, Murtaza Hussain

    2012-01-01

    The emergence of the digital media and computational tools has widened the doors for creativity. The cutting edge in the digital arts and role of new technologies can be explored for the possible creativity. This gives an opportunity to involve arts with technologies to make creative works. The interactive artworks are often installed in the places where multiple people can interact with the installation, which allows the art to achieve its purpose by allowing the people to observe and involve with the installation. The level of engagement of the audience depends on the various factors such as aesthetic satisfaction, how the audience constructs meaning, pleasure and enjoyment. The method to evaluate these experiences is challenging as it depends on integration between the artificial life and real life by means of human computer interaction. This research investigates "How Adriano fits for creative and interactive artwork installations?" using an artwork installation in the campus of NTNU (Norwegian University...

  13. Designing Software-Based Interactive Installations

    DEFF Research Database (Denmark)

    Andreasen, Troels; Juul, Niels Christian; Rosendahl, Mads

    2014-01-01

    What. This chapter focuses on software engineering principles with specific emphasis on interactive installations providing embodied, tangible, and immersive experiences for the user. Such installations may deliver light, image, sound, and movement through actuators and may provide interaction...... installations and support the description of the approach with a single case- a bumper car competition. Why. To some extent, standard techniques for software development can be adapted for interactive installations. However, there is a need to emphasize the unique aspects of installations, bringing tangible...... architecture as well as esthetic experience, artistic expression, and leisure aspects into focus. The approach presented here has this intended purpose. Where. Building on experience from conventional software development and with inspiration from interaction design and creative programming, this chapter...

  14. Should we geoengineer larger ice caps?

    CERN Document Server

    Haqq-Misra, Jacob

    2015-01-01

    The climate of Earth is susceptible to catastrophes that could threaten the longevity of human civilization. Geoengineering to reduce incoming solar radiation has been suggested as a way to mediate the warming effects of contemporary climate change, but a geoengineering program for thousands of years could also be used to enlarge the size of the polar ice caps and create a permanently cooler climate. Such a large ice cap state would make Earth less susceptible to climate threats and could allow human civilization to survive further into the future than otherwise possible. Intentionally extending Earth's glacial coverage will require uninterrupted commitment to this program for millenia but would ultimately reach a cooler equilibrium state where geoengineering is no longer needed. Whether or not this program is ever attempted, this concept illustrates the need to identify preference among potential climate states to ensure the long-term success of civilization.

  15. Status of the AlCap experiment

    CERN Document Server

    Litchfield, R Phillip

    2015-01-01

    The AlCap experiment is a joint project between the COMET and Mu2e collaborations. Both experiments intend to look for the lepton-flavour violating conversion $\\mu + A \\rightarrow e + A$, using tertiary muons from high-power pulsed proton beams. In these experiments the products of ordinary muon capture in the muon stopping target are an important concern, both in terms of hit rates in tracking detectors and radiation damage to equipment. The goal of the AlCap experiment is to provide precision measurements of the products of nuclear capture on Aluminium, which is the favoured target material for both COMET and Mu2e. The results will be used for optimising the design of both conversion experiments, and as input to their simulations. Data was taken in December 2013 and is currently being analysed.

  16. Greening CAP payments: a missed opportunity?

    Energy Technology Data Exchange (ETDEWEB)

    Matthews, Alan

    2013-01-15

    At an important point in the current reform of the Common Agricultural Policy (CAP), a new IIEA policy brief by Professor Alan Matthews, one of the EU’s foremost experts on the topic, considers proposals to green direct farm payments. Professor Matthews argues that proposed greening of direct payments – the key innovation in the current round of CAP Reform – look likely to fail. While greening may survive as a concept, the likely outcome of the negotiations between Agriculture Ministers and the European Parliament will deliver little practical environmental benefit. The paper examines the rationale underpinning greening, arguing that it exists to justify the continuation of a large agricultural budget, explores reasons for the apparent failure of the proposals, and reflects on the implications for future efforts to better integrate environmental objectives into EU agriculture policy. This is the first in a series of Environment Nexus policy briefs by leading experts in the fields of agriculture, energy, climate change and water.

  17. Cytocompatibility and Antibacterial Properties of Capping Materials

    OpenAIRE

    Claudio Poggio; Carla Renata Arciola; Riccardo Beltrami; Annachiara Monaco; Alberto Dagna; Marco Lombardini; Livia Visai

    2014-01-01

    The aim of this study was to evaluate and compare the antimicrobial activity and cytocompatibility of six different pulp-capping materials: Dycal (Dentsply), Calcicur (Voco), Calcimol LC (Voco), TheraCal LC (Bisco), MTA Angelus (Angelus), and Biodentine (Septodont). To evaluate antimicrobial activity, materials were challenged in vitro with Streptococcus mutans, Streptococcus salivarius, and Streptococcus sanguis in the agar disc diffusion test. Cytocompatibility of the assayed materials towa...

  18. Farmer preference for CAPS: Workshop and analysis

    OpenAIRE

    Reed, B.F.

    2012-01-01

    Analytic Hierarchy Process (AHP) is a a multi-criteria, multi-level decision-making method which breaks down complex decisions into a series of simple questions reflecting an optimal goal, objectives, and various options. This provides a structured technique for organizing and analyzing differing preferences for Conservation Agriculture Production Systems (CAPS). This presentation explains AHP and conducts a survey to collect gender-specific preference data for selected conservation agricultu...

  19. Toroidal, Counter-Toroidal, and Upwelling Flow in the Mantle Wedge of the Rivera and Cocos Plates: Implications for IOB Geochemistry in the Trans-Mexican Volcanic Belt

    Science.gov (United States)

    Neumann, Florian; Vásquez-Serrano, Alberto; Tolson, Gustavo; Negrete-Aranda, Raquel; Contreras, Juan

    2015-12-01

    We carried out analog laboratory modeling at a scale 1:4,000,000 and computer rendering of the flow patterns in a simulated western Middle American subduction zone. The scaled model consists of a transparent tank filled with corn syrup and housing two conveyor belts made of polyethylene strips. One of the strips dips 60° and moves at a velocity of 30 mm/min simulating the Rivera plate. The other one dips 45°, moves at 90 mm/min simulating the subduction of the Cocos plate. Our scaled subduction zone also includes a gap between the simulated slabs analogous to a tear recently observed in shear wave tomography studies. An acrylic plate 3 mm thick floats on the syrup in grazing contact with the polyethylene strips and simulates the overriding North America plate. Our experiments reveal a deep toroidal flow of asthenospheric mantle through the Cocos-Rivera separation. The flow is driven by a pressure gradient associated with the down-dip differential-motion of the slabs. Similarly, low pressure generated by the fast-moving Cocos plate creates a shallow counter-toroidal flow in the uppermost 100 km of the mantle wedge. The flow draws mantle beneath the western Trans-Mexican Volcanic Belt to the Jalisco block, then plunges into the deep mantle by the descending poloidal cell of the Cocos slab. Moreover, our model suggests a hydraulic jump causes an ~250 km asthenosphere upwelling around the area where intra-arc extensional systems converge in western Mexico. The upwelling eventually merges with the shallow counter-toroidal flow describing a motion in 3D space similar to an Archimedes' screw. Our results indicate the differential motion between subducting slabs drives mixing in the mantle wedge of the Rivera plate and allows the slab to steepen and retreat. Model results are in good agreement with seismic anisotropy studies and the geochemistry of lavas erupted in the Jalisco block. The model can explain the eruption of OIB lavas in the vicinity of the City of

  20. Toroidal, Counter-Toroidal, and Upwelling Flow in the Mantle Wedge of the Rivera and Cocos Plates: Implications for IOB Geochemistry in the Trans-Mexican Volcanic Belt

    Science.gov (United States)

    Neumann, Florian; Vásquez-Serrano, Alberto; Tolson, Gustavo; Negrete-Aranda, Raquel; Contreras, Juan

    2016-10-01

    We carried out analog laboratory modeling at a scale 1:4,000,000 and computer rendering of the flow patterns in a simulated western Middle American subduction zone. The scaled model consists of a transparent tank filled with corn syrup and housing two conveyor belts made of polyethylene strips. One of the strips dips 60° and moves at a velocity of 30 mm/min simulating the Rivera plate. The other one dips 45°, moves at 90 mm/min simulating the subduction of the Cocos plate. Our scaled subduction zone also includes a gap between the simulated slabs analogous to a tear recently observed in shear wave tomography studies. An acrylic plate 3 mm thick floats on the syrup in grazing contact with the polyethylene strips and simulates the overriding North America plate. Our experiments reveal a deep toroidal flow of asthenospheric mantle through the Cocos-Rivera separation. The flow is driven by a pressure gradient associated with the down-dip differential-motion of the slabs. Similarly, low pressure generated by the fast-moving Cocos plate creates a shallow counter-toroidal flow in the uppermost 100 km of the mantle wedge. The flow draws mantle beneath the western Trans-Mexican Volcanic Belt to the Jalisco block, then plunges into the deep mantle by the descending poloidal cell of the Cocos slab. Moreover, our model suggests a hydraulic jump causes an ~250 km asthenosphere upwelling around the area where intra-arc extensional systems converge in western Mexico. The upwelling eventually merges with the shallow counter-toroidal flow describing a motion in 3D space similar to an Archimedes' screw. Our results indicate the differential motion between subducting slabs drives mixing in the mantle wedge of the Rivera plate and allows the slab to steepen and retreat. Model results are in good agreement with seismic anisotropy studies and the geochemistry of lavas erupted in the Jalisco block. The model can explain the eruption of OIB lavas in the vicinity of the City of

  1. Protein synthesis in geostimulated root caps

    Science.gov (United States)

    Feldman, L. J.

    1982-01-01

    A study is presented of the processes occurring in the root cap of corn which are requisite for the formation of root cap inhibitor and which can be triggered or modulated by both light and gravity. The results of this study indicate the importance of protein synthesis for light-induced gravitropic bending in roots. Root caps in which protein synthesis is prevented are unable to induce downward bending. This suggests that light acts by stimulating proteins which are necessary for the translation of the gravitropic stimulus into a growth response (downward bending). The turnover of protein with time was also examined in order to determine whether light acts by stimulating the synthesis of unique proteins required for downward growth. It is found that auxin in combination with light allows for the translation of the gravitropic stimulus into a growth response at least in part through the modification of protein synthesis. It is concluded that unique proteins are stimulated by light and are involved in promoting the downward growth in roots which are responding to gravity.

  2. Pulp-Capping with Mineral Trioxide Aggregate

    Directory of Open Access Journals (Sweden)

    Peycheva Kalina

    2015-11-01

    Full Text Available There are two considerations for direct pulp capping - accidental mechanical pulp exposure and exposure caused by caries. Mineral trioxide aggregate (MTA was used as pulp-capping material to preserve the vitality of the pulpal tissues. Follow-up examinations revealed that treatment was successful in preserving pulpal vitality and continued development of the tooth. On the basis of available information, it appears that MTA is the material of choice for some clinical applications. Material and methods: Cases 18 - 8 teeth with grey MTA, 10 teeth with white MTA; diagnose: Pulpitis chronica ulcerosa, Electro pulpal test (EOD - 30-35 μA, pre-clinical X-ray - without changes in the structures, follow ups for 4 years. Successful treatments: without clinical symptoms and changes in the X-rays: 5 teeth with grey MTA, 8 teeth with white MTA for period of 4 years. Unsuccessful treatments: Clinical symptoms and sometimes changes in the X-ray: 3 with grey MTA, 2 with white MTA. MTA is an appropriate material for pulp-capping and follow-up examinations revealed that the treatment was successful in preserving pulpal vitality.

  3. Diagnostic criteria for cryopyrin-associated periodic syndrome (CAPS).

    Science.gov (United States)

    Kuemmerle-Deschner, Jasmin B; Ozen, Seza; Tyrrell, Pascal N; Kone-Paut, Isabelle; Goldbach-Mansky, Raphaela; Lachmann, Helen; Blank, Norbert; Hoffman, Hal M; Weissbarth-Riedel, Elisabeth; Hugle, Boris; Kallinich, Tilmann; Gattorno, Marco; Gul, Ahmet; Ter Haar, Nienke; Oswald, Marlen; Dedeoglu, Fatma; Cantarini, Luca; Benseler, Susanne M

    2016-10-04

    Cryopyrin-associated periodic syndrome (CAPS) is a rare, heterogeneous disease entity associated with NLRP3 gene mutations and increased interleukin-1 (IL-1) secretion. Early diagnosis and rapid initiation of IL-1 inhibition prevent organ damage. The aim of the study was to develop and validate diagnostic criteria for CAPS. An innovative process was followed including interdisciplinary team building, item generation: review of CAPS registries, systematic literature review, expert surveys, consensus conferences for item refinement, item reduction and weighting using 1000Minds decision software. Resulting CAPS criteria were tested in large cohorts of CAPS cases and controls using correspondence analysis. Diagnostic models were explored using sensitivity analyses. The international team included 16 experts. Systematic literature and registry review identified 33 CAPS-typical items; the consensus conferences reduced these to 14. 1000Minds exercises ranked variables based on importance for the diagnosis. Correspondence analysis determined variables consistently associated with the diagnosis of CAPS using 284 cases and 837 controls. Seven variables were significantly associated with CAPS (pCAPS-typical symptoms: urticaria-like rash, cold-triggered episodes, sensorineural hearing loss, musculoskeletal symptoms, chronic aseptic meningitis and skeletal abnormalities. Sensitivity was 81%, specificity 94%. It performed well for all CAPS subtypes and regardless of NLRP3 mutation. The novel approach integrated traditional methods of evidence synthesis with expert consensus, web-based decision tools and innovative statistical methods and may serve as model for other rare diseases. These criteria will enable a rapid diagnosis for children and adults with CAPS.

  4. Offshore Cable Installation - Lillgrund. Lillgrund Pilot Project

    Energy Technology Data Exchange (ETDEWEB)

    Unosson, Oscar (Vattenfall Vindkraft AB, Stockholm (Sweden))

    2009-01-15

    This report describes the installation method and the experiences gained during the installation of the submarine cables for the offshore wind farm at Lillgrund. The wind farm consists of 48 wind turbines and is expected to produce 0.33 TWh annually. Different aspects of the installation, such as techniques, co-operation between the installation teams, weather conditions and regulatory and environmental issues are described in this report. In addition, recommendations and guidelines are provided, which hopefully can be utilised in future offshore wind projects. The trenches, in which the submarine cables were laid, were excavated weeks before the cable laying. This installation technique proved to be successful for the laying of the inter array cables. The export cable, however, was laid into position with difficulty. The main reason why the laying of the export cable proved more challenging was due to practical difficulties connected with the barge entrusted with the cable laying, Nautilus Maxi. The barge ran aground a number of times and it had difficulties with the thrusters, which made it impossible to manoeuvre. When laying the inter array cables, the method specification was closely followed, and the laying of the cables was executed successfully. The knowledge and experience gained from the offshore cable installation in Lillgrund is essential when writing technical specifications for new wind plant projects. It is recommended to avoid offshore cable installation work in winter seasons. That will lower the chances of dealing with bad weather and, in turn, will reduce the risks

  5. Structural considerations for solar installers : an approach for small, simplified solar installations or retrofits.

    Energy Technology Data Exchange (ETDEWEB)

    Richards, Elizabeth H.; Schindel, Kay (City of Madison, WI); Bosiljevac, Tom; Dwyer, Stephen F.; Lindau, William (Lindau Companies, Inc., Hudson, WI); Harper, Alan (City of Madison, WI)

    2011-12-01

    Structural Considerations for Solar Installers provides a comprehensive outline of structural considerations associated with simplified solar installations and recommends a set of best practices installers can follow when assessing such considerations. Information in the manual comes from engineering and solar experts as well as case studies. The objectives of the manual are to ensure safety and structural durability for rooftop solar installations and to potentially accelerate the permitting process by identifying and remedying structural issues prior to installation. The purpose of this document is to provide tools and guidelines for installers to help ensure that residential photovoltaic (PV) power systems are properly specified and installed with respect to the continuing structural integrity of the building.

  6. Instability of Bucket Foundations during Installation

    DEFF Research Database (Denmark)

    Madsen, Søren; Andersen, Lars Vabbersgaard; Ibsen, Lars Bo

    The bucket foundation is an upcoming technology for offshore wind turbines. The bucket foundation is a large cylindrical monopod foundation constructed as a thin steel shell structure. A bucket foundation does not require heavy installation equipment since it is installed by suction forces....... The combination of a thin shell structure and suction forces leads to the fact that instability, in form of buckling, becomes a crucial issue during installation. The hydrostatic buckling pressure of the bucket foundation is addressed using three-dimensional, non-linear finite element analysis. The results...

  7. Phosphogypsum capping depth affects revegetation and hydrology in Western Canada.

    Science.gov (United States)

    Jackson, Mallory E; Naeth, M Anne; Chanasyk, David S; Nichol, Connie K

    2011-01-01

    Phosphogypsum (PG), a byproduct of phosphate fertilizer manufacturing, is commonly stacked and capped with soil at decommissioning. Shallow (0, 8, 15, and 30 cm) and thick (46 and 91 cm) sandy loam caps on a PG stack near Fort Saskatchewan, Alberta, Canada, were studied in relation to vegetation establishment and hydrologic properties. Plant response was evaluated over two growing seasons for redtop ( L.), slender wheatgrass ( (Link) Malte ex H.F. Lewis), tufted hairgrass ( (L.) P. Beauv.), and sheep fescue ( L.) and for a mix of these grasses with alsike clover ( L.). Water content below the soil-PG interface was monitored with time-domain reflectometry probes, and leachate water quantity and quality at a depth of 30 cm was measured using lysimeters. Vegetation responded positively to all cap depths relative to bare PG, with few significant differences among cap depths. Slender wheatgrass performed best, and tufted hairgrass performed poorly. Soil caps <1 m required by regulation were sufficient for early revegetation. Soil water fluctuated more in shallow than in thick caps, and water content was generally between field capacity and wilting point regardless of cap depth. Water quality was not affected by cap depths ≤30 cm. Leachate volumes at 30 cm from distinct rainfall events were independent of precipitation amount and cap depth. The study period had lower precipitation than normal, yet soil caps were hospitable for plant growth in the first 2 yr of establishment.

  8. GPS/CAPS dual-mode software receiver

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The positioning of the GPS or Chinese Area Positioning System (CAPS) software receiver was developed on a software receiver platform. The structure of the GPS/CAPS dual-mode software receiver was put forward after analyzing the differences in the satellite identification, ranging code, spread spectrum, coordinate system, time system, carrier band, and navigation data between GPS and CAPS. Based on Matlab software on a personal computer, baseband signal processing and positioning procedures were completed using real GPS and CAPS radio frequency signals received by two antennas. Three kinds of experiments including GPS positioning, CAPS positioning, and GPS/CAPS positioning were carried out. Stability and precision of the results were analyzed and compared. The experimental results show that the precision of CAPS is similar to that of GPS, while the positioning precision of the GPS/CAPS dual-mode software receiver is 1-2 m higher than that of CAPS or GPS. The smallest average variance of the positioning can be obtained by using the GPS/CAPS dual-mode software receiver.

  9. GPS/CAPS dual-mode software receiver

    Institute of Scientific and Technical Information of China (English)

    NING ChunLin; SHI HuLi; HU Chao

    2009-01-01

    The positioning of the GPS or Chinese Area Positioning System (CAPS) software receiver was developed on a software receiver platform.The structure of the GPSlCAPS dual-mode software receiver was put forward after analyzing the differences in the satellite identification,ranging code,spread spectrum,coordinate system,time system,carrier band,and navigation data between GPS and CAPS.Based on Matlab software on a personal computer,baseband signal processing and positioning procedures were completed using real GPS and CAPS radio frequency signals received by two antennas.Three kinds of experiments including GPS positioning,CAPS positioning,and GPS/CAPS positioning were carried out.Stability and precision of the results were analyzed and compared.The experimental results show that the precision of CAPS is similar to that of GPS,while the positioning precision of the GPS/CAPS dual-mode software receiver is 1-2 m higher than that of CAPS or GPS.The smallest average variance of the positioning can be obtained by using the GPS/CAPS dual-mode software receiver.

  10. Study on Alignment Technology of CAP1400 Reactor Internals%CAP1400堆内构件对中检测技术研究

    Institute of Scientific and Technical Information of China (English)

    舒华安; 童庆军; 王盛; 郝磊; 郭健

    2016-01-01

    对中检测是CAP1400堆内构件制造装配的关键检测技术,针对传统光学对中方法的检测结果易受环境和人眼观测误差影响,且作业时间受限等缺点,开发了激光垂准—CCD光靶数据采集处理的新型对中检测方法。通过专用试验平台进行对中比对试验,结果表明该方法测量精度高,成功避免了传统方法的缺点,为堆内构件制造及核电站现场安装提供了新的对中检测方法。%The alignment measurement is the key technology of CAP1400 reactor interal manufacturing and assembly. Traditional method using micrometer collimating telescope has high requirements on the operating environment, operation time. The system of Laser Vertical-CCD optical target data acquisition and processing is developed. The comparison tests made through the special test platform show that the method has high accuracy of measurement. The disadvantages of the traditional optical measurement is avoided. A new method for manufacturing and installation of reactor internal is gained.

  11. Subsea flexible flowline installation issues and solutions

    Institute of Scientific and Technical Information of China (English)

    Kevin Huang

    2013-01-01

    Flexible flowlines and risers have been increasingly used for deepwater and ultra-deepwater field applications,partially because of its low submerged weight and better dynamic characteristics comparing to rigid pipelines.The offshore installation of flowline may have advantages as well.However,it has special needs for the installation aids,and it is challenging to install tie-in structures due to its low bending stiffness.This paper is to present some of the challenges during a recent flexible installation project with a total of more than 100 km flexible flowlines,and 24 in-line sleds/pipeline end termination(PLET) in water depth up to 1 300 m.

  12. Structural Code Considerations for Solar Rooftop Installations.

    Energy Technology Data Exchange (ETDEWEB)

    Dwyer, Stephen F.; Dwyer, Brian P.; Sanchez, Alfred

    2014-12-01

    Residential rooftop solar panel installations are limited in part by the high cost of structural related code requirements for field installation. Permitting solar installations is difficult because there is a belief among residential permitting authorities that typical residential rooftops may be structurally inadequate to support the additional load associated with a photovoltaic (PV) solar installation. Typical engineering methods utilized to calculate stresses on a roof structure involve simplifying assumptions that render a complex non-linear structure to a basic determinate beam. This method of analysis neglects the composite action of the entire roof structure, yielding a conservative analysis based on a rafter or top chord of a truss. Consequently, the analysis can result in an overly conservative structural analysis. A literature review was conducted to gain a better understanding of the conservative nature of the regulations and codes governing residential construction and the associated structural system calculations.

  13. Buckling of Bucket Foundations During Installation

    DEFF Research Database (Denmark)

    Madsen, Søren

    axial and latteral pressure during the installation process buckling becomes a crucial design consideration. In 2005, a large wind turbine was to be installed nearshore the harbour in Wilhelmshaven, Germany. The windturbine was never erected since the skirt of the bucket foundation buckled during...... the suction assisted installation process. In this thesis, the phenomenon of buckling of the bucket foundation during installation is investigated by means of Finite Element Analysis. The influence of boundary conditions on the bucket foundation is adressed as well as the effect of including the surrounding...... soil and soil–structure interaction. Investigations are made regarding the buckling incident in Wilhelmshaven and the results are compared to current DNV and Eurocode standards. Finally, analysis of a new design of the cross section with a higher buckling capacity than an equivalent circular cross...

  14. Design, fabrication and installation of irradiation facilities

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Sung; Lee, C. Y.; Kim, J. Y.; Chi, D. Y.; Kim, S. H.; Ahn, S. H.; Kim, S. J.; Kim, J. K.; Yang, S. H.; Yang, S. Y.; Kim, H. R.; Kim, H.; Lee, K. H.; Lee, B. C.; Park, C.; Lee, C. T.; Cho, S. W.; Kwak, K. K.; Suk, H. C. [and others

    1997-07-01

    The principle contents of this project are to design, fabricate and install the steady-state fuel test loop and non-instrumented capsule in HANARO for nuclear technology development. This project will be completed in 1999, the basic and detail design, safety analysis, and procurement of main equipment for fuel test loop have been performed and also the piping in gallery and the support for IPS piping in reactor pool have been installed in 1994. In the area of non-instrumented capsule for material irradiation test, the fabrication of capsule has been completed. Procurement, fabrication and installation of the fuel test loop will be implemented continuously till 1999. As besides, as these irradiation facilities will be installed in HANARO, review of safety concern, discussion with KINS for licensing and safety analysis report has been submitted to KINS to get a license and review of HANARO interface have been performed respectively. (author). 39 refs., 28 tabs., 21 figs.

  15. RF accelerating unit installed in the PSB

    CERN Multimedia

    1972-01-01

    RF accelerating unit installed in the PSB ring between two bending magnets. Cool air from a heat exchanger is injected into the four cavities from the central feeder and the hot air recirculated via the lateral ducts.

  16. Installation of the LHC transfer lines begins

    CERN Multimedia

    Patrice Loïez

    2003-01-01

    The first of 700 magnets has been installed in one of the two transfer tunnels built to transfer the SPS beam into the LHC. The start of this first installation phase of the LHC transfer lines provides the opportunity to launch a new and highly original modular system for transporting and installing all kinds of magnets in very narrow tunnels. The system is based on very compact bogies, up to four of which can be coupled together to form a convoy. The wheels are fitted with individual motors enabling them to swivel through an angle of 90° and the convoy to move laterally. In this way the magnet is delivered directly to its installation point, but beneath the beamline. It is then raised into its final position in the beamline using air cushions, which form an integrated part of the transport system. Here we see the transport vehicle alongside the magnet supports. Visible in the background is the first magnet in place.

  17. Notes on LED Installations in Street Illumination

    Directory of Open Access Journals (Sweden)

    Elisabeta Spunei

    2014-09-01

    Full Text Available The paper presents a study made on choosing LED street lighting installations, such that the quality requirements for exterior artificial lighting are fulfilled. We analyze two types of LED street lighting installations from a technical point of view, together with lighting level and brightness values obtained during the measurements. Following on the field measurements, the lighting quality parameters are calculated, and, for the lighting installation with the best performance, optimal mounting suggestions are made. The optimal quality parameters are calculated by simulations using the Dialux software. The same software and the same light sources we also compute an optimal street lighting by determining the size of the installation that provides the best lighting parameter values.

  18. Prototype solar-heating system - installation manual

    Science.gov (United States)

    1978-01-01

    Manual for prototype solar-heating system gives detailed installation procedures for each of seven subsystems. Procedures for operation and maintenance are also included. It discusses architectural considerations, building construction considerations, and checkout-test procedures.

  19. Towards a Framework for Projection Installations

    DEFF Research Database (Denmark)

    Halskov, Kim; Falck, Hans William

    2013-01-01

    Projection installations are part of Spatially Augmented Reality, where the projection medium is used to enrich a fixed, bounded physical space with digital content. Projection technology enables us to turn many kinds of physical objects into displays. In this paper we develop and present a conce...... concerning urban computing, including media architecture.......Projection installations are part of Spatially Augmented Reality, where the projection medium is used to enrich a fixed, bounded physical space with digital content. Projection technology enables us to turn many kinds of physical objects into displays. In this paper we develop and present...... a conceptual framework that addresses three aspects of a projection installation: the contentassociated with the object, the digital content, and the relation between the two. We conclude the paper with a set of strategies commonly used in projection installations: Enhancing or emphasizing physical aspects...

  20. Toroidal Variable-Line-Space Gratings: The Good, the Bad and The Ugly

    Science.gov (United States)

    West, Edward A.; Kobayashi, Ken; Cirtain, Jonathan; Gary, Allen; Davis, John; Reader, Joseph

    2009-01-01

    Toroidal variable-line-space (VLS) gratings are an important factor in the design of an efficient VUV solar telescope that will measure the CIV (155nm) and MgII (280nm) emissions lines in the Sun's transition region. In 1983 Kita and Harada described spherical VLS gratings but the technology to commercially fabricate these devices is a recent development, especially for toroidal surfaces. This paper will describe why this technology is important in the development of the Solar Ultraviolet Magnetograph Investigation (SUMI) sounding rocket program (the good), the delays due to the conversion between the TVLS grating design and the optical fabrication (the bad), and finally the optical testing, alignment and tolerancing of the gratings (the ugly). The Solar Ultraviolet Magnetograph Investigation, SUMI, has been reported in several papers since this program began in 2000. The emphasis of this paper is to describe SUMI's Toroidal Variable-Line-Space (TVLS) gratings. These gratings help SUMI meet its scientific goals which require both high spectral resolution and high optical efficiency for magnetic field measurements in the vacuum ultraviolet wavelength band of the solar spectrum (the good). Unfortunately, the technology readiness level of these gratings has made their implementation difficult, especially for a sounding rocket payload (the bad). Therefore, this paper emphasizes the problems and solutions that were developed to use these gratings in SUMI (the ugly). Section 2 contains a short review of the scientific goals of SUMI and why this mission is important in the understanding of the 3D structure of the magnetic field on the Sun. The flight hardware that makes up the SUMI payload is described in Section 3 with emphasis on those components that affect the TVLS gratings. Section 4 emphasizes the alignment, testing and optical modeling that were developed to optimize the performance of these gratings.

  1. Neoclassical toroidal torque generation by auxiliary heating in non-axisymmetric tori

    Science.gov (United States)

    Lazzaro, E.; Nowak, S.; Sauter, O.

    2016-12-01

    In conditions of ideal axisymmetry, for a magnetized plasma in a generic bounded domain, necessarily toroidal, the uniform absorption of external energy (e.g. rf or isotropic alpha heating) clearly cannot give rise to net forces or torques. A rather common experimental observation on contemporary tokamaks is that the near central absorption of auxiliary heating power (often ICH, ECH, and LHCD) and current drive in presence of non axisymmetric magnetic perturbations, including tearing modes, drives a bulk plasma rotation in the co  -  I p direction. Also growing tearing modes provide a nonlinear magnetic braking that tends to flatten the rotation profile and clamp it at the q-rational surfaces. The physical origin of the torque associated with P aux absorption could be due the effects of asymmetry in deposition or in the equilibrium configuration, but here we consider also the effect of the response of the so called neoclassical offset velocity to the power dependent heat flow increment. The neoclassical toroidal viscosity (NTV), due to error fields, internal magnetic kink or tearing modes tends to relax the plasma rotation to this asymptotic speed, which in absence of auxiliary heating is of the order of the ion diamagnetic velocity. It can be shown by a kinetic calculation, this offset velocity is a function of the absorbed heat and therefore of the injected auxiliary power, thereby forcing the plasma rotation in a direction opposite to the initial, to large values. The problem is discussed in the frame of the theoretical models of neoclassical toroidal viscosity.

  2. Software Management Environment (SME) installation guide

    Science.gov (United States)

    Kistler, David; Jeletic, Kellyann

    1992-01-01

    This document contains installation information for the Software Management Environment (SME), developed for the Systems Development Branch (Code 552) of the Flight Dynamics Division of Goddard Space Flight Center (GSFC). The SME provides an integrated set of management tools that can be used by software development managers in their day-to-day management and planning activities. This document provides a list of hardware and software requirements as well as detailed installation instructions and trouble-shooting information.

  3. Improving Energy Security for Air Force Installations

    Science.gov (United States)

    Schill, David

    Like civilian infrastructure, Air Force installations are dependent on electrical energy for daily operations. Energy shortages translate to decreased productivity, higher costs, and increased health risks. But for the United States military, energy shortages have the potential to become national security risks. Over ninety-five percent of the electrical energy used by the Air Force is supplied by the domestic grid, which is susceptible to shortages and disruptions. Many Air Force operations require a continuous source of energy, and while the Air Force has historically established redundant supplies of electrical energy, these back-ups are designed for short-term outages and may not provide sufficient supply for a longer, sustained power outage. Furthermore, it is the goal of the Department of Defense to produce or procure 25 percent of its facility energy from renewable sources by fiscal year 2025. In a government budget environment where decision makers are required to provide more capability with less money, it is becoming increasingly important for informed decisions regarding which energy supply options bear the most benefit for an installation. The analysis begins by exploring the field of energy supply options available to an Air Force installation. The supply options are assessed according to their ability to provide continuous and reliable energy, their applicability to unique requirements of Air Force installations, and their costs. Various methods of calculating energy usage by an installation are also addressed. The next step of this research develops a methodology and tool which assesses how an installation responds to various power outage scenarios. Lastly, various energy supply options are applied to the tool, and the results are reported in terms of cost and loss of installation capability. This approach will allow installation commanders and energy managers the ability to evaluate the cost and effectiveness of various energy investment options.

  4. Quantifying Solar Wind-Polar Cap Interactions

    Science.gov (United States)

    Urban, K. D.; Gerrard, A. J.; Lanzerotti, L. J.; Weatherwax, A. T.; Huang, Y.

    2015-12-01

    It is well known that the solar wind is a major driver of ultra-low frequency [ULF] power at ground locations from low to high latitudes. However, due to the scarcity of deep polar cap magnetometer sites, it is not clear when, where, or if this is true deep inside the polar cap on open field lines where interplanetary magnetic field [IMF] ULF waves could possibly be directly detected. Given recent observations of very large Joule heating estimates from DMSP data, together with the large heating reported by the CHAMP satellite, it is important to understand the degree to which ULF waves in the solar wind can directly cause such heating. Using a time series of lagged correlation sequences ("dynamic correlograms") between GSM Bz ULF power (computed via data obtained from NASA's Advanced Composition Explorer [ACE] ahead of Earth in the solar wind) and the horizontal ULF power (H^2=N^2+E^2) from ground-based magnetometers in Earth's southern polar cap, we investigate the direct penetration of ULF waves from the solar wind into the polar ionosphere during a gamut of space weather conditions at a distributed network of Automated Geophysical Observatories [AGOs] in Antarctica. To infer causation, a predicted lag correlation maximum at each time step is computed by simply dividing the associated distance of ACE from Earth by the concurrent bulk solar wind speed. This technique helps parse out direct penetration of solar wind ULF waves from other sources (e.g., via leakage from closed field line resonances due to the bulk solar wind plasma viscously interacting at dawn/dusk flanks inducing Kelvin-Helmholtz instabilities [KHI] or compressional modes induced by impulses in solar wind dynamic pressure). The identified direct-penetrating ULF waves are related to the DMSP-derived Poynting fluxes by regression analysis, and conclusions are drawn for the importance of the ULF source for the measured heating.

  5. Evaluation of toroidal torque by non-resonant magnetic perturbations in tokamaks for resonant transport regimes using a Hamiltonian approach

    Science.gov (United States)

    Albert, Christopher G.; Heyn, Martin F.; Kapper, Gernot; Kasilov, Sergei V.; Kernbichler, Winfried; Martitsch, Andreas F.

    2016-08-01

    Toroidal torque generated by neoclassical viscosity caused by external non-resonant, non-axisymmetric perturbations has a significant influence on toroidal plasma rotation in tokamaks. In this article, a derivation for the expressions of toroidal torque and radial transport in resonant regimes is provided within quasilinear theory in canonical action-angle variables. The proposed approach treats all low-collisional quasilinear resonant neoclassical toroidal viscosity regimes including superbanana-plateau and drift-orbit resonances in a unified way and allows for magnetic drift in all regimes. It is valid for perturbations on toroidally symmetric flux surfaces of the unperturbed equilibrium without specific assumptions on geometry or aspect ratio. The resulting expressions are shown to match the existing analytical results in the large aspect ratio limit. Numerical results from the newly developed code NEO-RT are compared to calculations by the quasilinear version of the code NEO-2 at low collisionalities. The importance of the magnetic shear term in the magnetic drift frequency and a significant effect of the magnetic drift on drift-orbit resonances are demonstrated.

  6. Radioactive airborne effluents and the environmental impact assessment of CAP1400 nuclear power plant under normal operation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qiong; Guo, RuiPing; Zhang, ChunMing; Chen, XiaoQiu; Wang, Bo, E-mail: wangbo@chinansc.cn

    2014-12-15

    Highlights: • Typical radionuclides dispersion from CAP1400 under normal operation was simulated. • Modified Gaussian model considered radioactive decay, dry and wet deposition and so on. • The radioactive impact pathways on the public through atmosphere were compared. • The maximum individual effective dose was lower than the public irradiation limit. - Abstract: China Advanced Passive nuclear power plant with installed capacity reaching to 1400 MW (CAP1400) is independently designed as the China's state-of-the-art third generation nuclear power brand based on AP1000 technology digestion and absorption. The concentration of typical radionuclides dispersed from CAP1400 under normal operation was calculated with modified Gaussian model, considering mixed layer height, dry deposition, wet deposition, radioactive decay and so on. The atmospheric dispersion factors, ground deposition rate, individual dose and public dose were also investigated to estimate the radioactive effects of CAP1400 under normal operation on surrounding environment and human beings. The radioactive impact pathways on the public through atmosphere, such as immersion irradiation in the smoke plume, internal irradiation from ingestion and inhalation and external irradiation from surface deposition were briefly introduced with focus on the comparison of the maximum individual effective dose to different group from atmospheric dispersion. All computation results show that the maximum individual irradiation dose happened to children with total effective irradiation dose of 4.52E−03 mSv/y, which was lower than the public irradiation limit of 0.25 mSv/y.

  7. SKF TOROIDAL ROLLER BEARING CARB – PRODUCTIVITY IMPROVEMENT AND MAINTENANCE COST REDUCTION THROUGH RELIABILITY AND SUSTAINABILITY

    Directory of Open Access Journals (Sweden)

    Tiberiu LAURIAN

    2010-06-01

    Full Text Available The CARB bearing is a single row bearing with long, slightly crowned symmetrical rollers. It combines the self-aligning capability of the spherical roller bearing with the unconstrained axial displacement ability of the cylindrical roller bearing. The optimal combination of both raceway profiles provides a favorable load distribution in the bearing, as well as low frictional running. This paper emphasizes the functioning characteristics of the SKF CARB toroidal roller bearing by means of a multibody dynamics simulation. Different conditions like load direction, races relative position or angular misalignment, are taken into consideration.

  8. Summary of US-Japan Exchange 2004 New Directions and Physics for Compact Toroids

    Energy Technology Data Exchange (ETDEWEB)

    Intrator, T; Nagata, M; Hoffman, A; Guo, H; Steinhauer, L; Ryutov, D; Miller, R; Okada, S

    2005-08-15

    This exchange workshop was an open meeting coordinated by the P-24 Plasma Physics Group at Los Alamos National Laboratory. We brought together scientists from institutions in the US and Japan who are researching the various and complementary types of Compact Toroids (CT). Many concepts, including both experimental and theoretical investigations, are represented. The range spans Field Reversed Configuration (FRC), spheromak, Reversed Field Pinch (RFP), spherical tokamaks, linear devices dedicated to fundamental physics studies, and hybrid transitions that bridge multiple configurations. The participants represent facilities on which significant experiments are now underway: FRC Injection experiment (FIX), Translation Confinement experiment (TCS), Nihon-University Compact Torus Experiment (NUCTE), HITSI (Helicity Injection experiment, Steady Inductive Helicity Injection (HIT-SIHI)), Field Reversed Configuration experiment-Liner (FRX-L), TS-3/4, Sustained Spheromak Experiment (SSPX), Relaxation Scaling Experiment (RSX), HIST, Caltech Spheromak, or in the design process such as MRX-FRC (PPPL), Pulsed High Density experiment (PHD at UW). Several new directions and results in compact toroid (CT) research have recently emerged, including neutral-beam injection, rotating magnetic fields, flux build up from Ohmic boost coils, electrostatic helicity injection techniques, CT injection into other large devices, and high density configurations for applications to magnetized target fusion and translational compression of CT's. CT experimental programs in both the US and Japan have also shown substantial progress in the control and sustainment of CT's. Both in theory and experiment, there is increased emphasis on 3D dynamics, which is also related to astrophysical and space physics issues. 3D data visualization is now frequently used for experimental data display. There was much discussion of the effects of weak toroidal fields in FRC's and possible implications

  9. A novel synthetic aperture technique for breast tomography with toroidal arrays

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Lianjie [Los Alamos National Laboratory; Simonetti, Francesco [IMPERIAL COLLEGE

    2009-01-01

    Ultrasound is commonly used as an adjunct to mammography for diagnostic evaluation of suspicions arising from breast cancer screening. As an alternative to conventional sonography that uses hand-held transducers, toroidal array probes that encircle the breast immersed in a water bath have been investigated for ultrasound tomography. This paper introduces a new method for three-dimensional synthetic aperture diffraction tomography that maximizes the resolution in the scanning direction and provides quantitative reconstructions of the acoustic properties of the object. The method is validated by means of numerical simulations.

  10. Demountable Toroidal Field Magnets for Use in a Compact Modular Fusion Reactor

    Science.gov (United States)

    Mangiarotti, F. J.; Goh, J.; Takayasu, M.; Bromberg, L.; Minervini, J. V.; Whyte, D.

    2014-05-01

    A concept of demountable toroidal field magnets for a compact fusion reactor is discussed. The magnets generate a magnetic field of 9.2 T on axis, in a 3.3 m major radius tokamak. Subcooled YBCO conductors have a critical current density adequate to provide this large magnetic field, while operating at 20 K reduces thermodynamic cooling cost of the resistive electrical joints. Demountable magnets allow for vertical replacement and maintenance of internal components, potentially reducing cost and time of maintenance when compared to traditional sector maintenance. Preliminary measurements of contact resistance of a demountable YBCO electrical joint between are presented.

  11. Comparative investigation of ELM control based on toroidal modelling of plasma response to RMP fields

    Science.gov (United States)

    Liu, Yueqiang

    2016-10-01

    The type-I edge localized mode (ELM), bursting at low frequency and with large amplitude, can channel a substantial amount of the plasma thermal energy into the surrounding plasma-facing components in tokamak devices operating at the high-confinement mode, potentially causing severe material damages. Learning effective ways of controlling this instability is thus an urgent issue in fusion research, in particular in view of the next generation large devices such as ITER and DEMO. Among other means, externally applied, three-dimensional resonant magnetic perturbation (RMP) fields have been experimentally demonstrated to be successful in mitigating or suppressing the type-I ELM, in multiple existing devices. In this work, we shall report results of a comparative study of ELM control using RMPs. Comparison is made between the modelled plasma response to the 3D external fields and the observed change of the ELM behaviour on multiple devices, including MAST, ASDEX Upgrade, EAST, DIII-D, JET, and KSTAR. We show that toroidal modelling of the plasma response, based on linear and quasi-linear magnetohydrodynamic (MHD) models, provides essential insights that are useful in interpreting and guiding the ELM control experiments. In particular, linear toroidal modelling results, using the MARS-F code, reveal the crucial role of the edge localized peeling-tearing mode response during ELM mitigation/suppression on all these devices. Such response often leads to strong peaking of the plasma surface displacement near the region of weak equilibrium poloidal field (e.g. the X-point), and this provides an alternative practical criterion for ELM control, as opposed to the vacuum field based Chirikov criteria. Quasi-linear modelling using MARS-Q provides quantitative interpretation of the side effects due to the ELM control coils, on the plasma toroidal momentum and particle confinements. The particular role of the momentum and particle fluxes, associated with the neoclassical toroidal

  12. Nonaxisymmetric Rossby vortex instability with toroidal magnetic fields in structured disks

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Cong [Los Alamos National Laboratory; Li, Hui [Los Alamos National Laboratory

    2009-01-01

    We investigate the global nonaxisymmetric Rossby vortex instability (RVI) in a differentially rotating, compressible magnetized accretion disk with radial density structures. Equilibrium magnetic fields are assumed to have only the toroidal component. Using linear theory analysis, we show that the density structure can be unstable to nonaxisymmetric modes. We find that, for the magnetic field profiles we have studied, magnetic fields always provide a stabilizing effect to the unstable RVI modes. We discuss the physical mechanism of this stabilizing effect. The threshold and properties of the unstable modes are also discussed in detail. In addition, we present linear stability results for the global magnetorotational instability when the disk is compressible.

  13. Spectrally Efficient OFDMA Lattice Structure via Toroidal Waveforms on the Time-Frequency Plane

    Directory of Open Access Journals (Sweden)

    Sultan Aldirmaz

    2010-01-01

    Full Text Available We investigate the performance of frequency division multiplexed (FDM signals, where multiple orthogonal Hermite-Gaussian carriers are used to increase the bandwidth efficiency. Multiple Hermite-Gaussian functions are modulated by a data set as a multicarrier modulation scheme in a single time-frequency region constituting toroidal waveform in a rectangular OFDMA system. The proposed work outperforms in the sense of bandwidth efficiency compared to the transmission scheme where only single Gaussian pulses are used as the transmission base. We investigate theoretical and simulation results of the proposed methods.

  14. Toroidal Nuclear Matter Distributions of Superheavy Nuclei from Constrained Skyrme-HFB Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Kosior, Amelia [Maria Curie-Sklodowska University, Poland; Staszczak, A. [Maria Curie-Sklodowska University, Poland; Wong, Cheuk-Yin [ORNL

    2017-01-01

    Using the Hartree Fock Bogoliubov (HFB) self-consistent mean-field theory with the SkM* Skyrme energy-density functional, we study nuclear structure properties of even even superheavy nuclei (SHN) of Z = 120 isotopes and N = 184 isotones. The shape of the nucleus along the lowest energy curve as a function of the quadrupole moment Q20 makes a sud- den transition from the oblate spheroids (biconcave discs) to the toroidal shapes, in the region of large oblate quadrupole moments.

  15. Conceptual studies of toroidal field magnets for the tokamak experimental power reactor. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Buncher, B.R.; Chi, J.W.H.; Fernandez, R.

    1976-10-26

    This report documents the principal results of a Conceptual Design Study for the Superconducting Toroidal Field System for a Tokamak Experimental Power Reactor. Two concepts are described for peak operating fields at the windings of 8 tesla, and 12 tesla, respectively. The design and manufacturing considerations are treated in sufficient detail that cost and schedule estimates could be developed. Major uncertainties in the design are identified and their potential impact discussed, along with recommendations for the necessary research and development programs to minimize these uncertainties. The minimum dimensions of a sub-size test coil for experimental qualification of the full size design are developed and a test program is recommended.

  16. Effects of energetic particles on zonal flow generation by toroidal Alfven eigenmode

    CERN Document Server

    Qiu, Zhiyong; Zonca, Fulvio

    2016-01-01

    Generation of zonal ow (ZF) by energetic particle (EP) driven toroidal Alfven eigenmode (TAE) is investigated using nonlinear gyrokinetic theory. It is found that, nonlinear resonant EP contri- bution dominates over the usual Reynolds and Maxwell stresses due to thermal plasma nonlinear response. ZF can be forced driven in the linear growth stage of TAE, with the growth rate being twice the TAE growth rate. The ZF generation mechanism is shown to be related to polarization induced by resonant EP nonlinearity. The generated ZF has both the usual meso-scale and micro- scale radial structures. Possible consequences of this forced driven ZF on the nonlinear dynamics of TAE are also discussed.

  17. Frequency Spectrum of Fluctuations Near a Rational Surface in a Toroidal Heliac

    Science.gov (United States)

    Zama, Tatsuya; Kitajima, Sumio; Takayama, Masakazu; Takeuchi, Nobunao; Watanabe, Hiroshige

    1993-03-01

    Density and space potential fluctuations have been studied in electron cyclotron resonance heating (ECRH) plasma of a helical axis stellarator TU Heliac using Langmuir probe techniques. These fluctuations are coherent and global, which can be explained by a drift instability model in cylindrical geometry. A particular fluctuation mode vanishes inside a rational surface. The ratio of this mode, n/m, corresponds to the rotational transform \\includegraphics{dummy.eps} of this rational surface, (m, n: poloidal, toroidal fluctuation modes, respectively). This phenomenon near the rational surface can also be explained by a drift instability theory.

  18. Finite-orbit-width effects on the geodesic acoustic mode in the toroidally rotating tokamak plasma

    CERN Document Server

    Ren, Haijun

    2016-01-01

    The Landau damping of geodesic acoustic mode (GAM) in a torodial rotating tokamak plasma is analytically investigated by taking into account the finite-orbit-width (FOW) resonance effect to the 3rd order. The analytical result is shown to agree well with the numerical solution. The dependence of the damping rate on the toroidal Mach number $M$ relies on $k_r \\rho_i$. For sufficiently small $k_r \\rho_i$, the damping rate monotonically decreases with $M$. For relatively large $k_r \\rho_i$, the damping rate increases with $M$ until approaching the maximum and then decreases with $M$.

  19. Toroidal silicon polarization analyzer for resonant inelastic x-ray scattering.

    Science.gov (United States)

    Gao, Xuan; Casa, Diego; Kim, Jungho; Gog, Thomas; Li, Chengyang; Burns, Clement

    2016-08-01

    Resonant Inelastic X-ray Scattering (RIXS) is a powerful probe for studying electronic excitations in materials. Standard high energy RIXS measurements do not measure the polarization of the scattered x-rays, which is unfortunate since it carries information about the nature and symmetry of the excitations involved in the scattering process. Here we report the fabrication of thin Si-based polarization analyzers with a double-concave toroidal surface, useful for L-edge RIXS studies in heavier atoms such as the 5-d transition metals.

  20. Poloidal flow and toroidal particle ring formation in a sessile drop driven by megahertz order vibration.

    Science.gov (United States)

    Rezk, Amgad R; Yeo, Leslie Y; Friend, James R

    2014-09-23

    Poloidal flow is curiously formed in a microliter sessile water drop over 157-225 MHz because of acoustic streaming from three-dimensional standing Lamb waves in a lithium niobate substrate. The flow possesses radial symmetry with downwelling at the center and upwelling around the periphery of the drop. Outside this frequency range, the attenuation occurs over a length scale incompatible with the drop size and the poloidal flow vanishes. Remarkably, shear-induced migration was found to drive toroidal particle ring formation with diameters inversely proportional to the frequency of the acoustic irradiation.

  1. Transport of Parallel Momentum by Toroidal Ion Temperature Gradient Instability near Marginality

    Energy Technology Data Exchange (ETDEWEB)

    E.S. Yoon and T.S. Hahm

    2009-10-20

    The turbulent angular momentum flux carried by ions resonant with toroidal ion temperature gradient(ITG) instability is calculated via quasilinear calculation using the phase-space conserving gyrokinetic equation in the laboratory frame. The results near ITG marginality indicate that the inward turbulent equipartition (TEP) momentum pinch [Hahm T.S. et al 2007 Phys. Plasmas 14 072302] remains as the most robust part of pinch. In addition, ion temperature gradient driven momentum flux is inward for typical parameters, while density gradient driven momentum flux is outward as in the previous kinetic result in slab geometry [Diamond P.H. et al 2008 Phys. Plasmas 15 012303].

  2. Using a priori knowledge for developing bolometric tomography in toroidal devices

    Science.gov (United States)

    Sano, Ryuichi; Peterson, Byron J.; Mukai, Kiyofumi; Teranishi, Masaru; Iwama, Naofumi; Kobayashi, Masahiro

    2016-11-01

    In tomographic imaging of magnetically confined toroidal plasmas, a countermeasure against missing observation has been studied in terms of the adoption of prior information based on modelled plasma profiles. The Tikhonov regularization for image reconstruction is extended by the use of the Euclidean distance. A procedure of model fitting is designed in order to adaptively generate the reference image. The new method is tested on a typical example of ill-conditioned tomography, that is, the three-dimensional imaging-bolometer tomography in the large helical device. It has been found that the new method is useful for diminishing artifacts and thus for better recognizing the radiation structure of plasma.

  3. Stabilisation of ballooning modes in torsatrons with an externally applied toroidal current

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, W.A. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)

    1996-09-01

    It has been found that ideal ballooning modes can impose very restrictive volume average {beta} limits in torsatrons much below the typical values close to 5% that are required to be economically realisable as reactor systems and it has been shown that externally applied toroidal currents that are peaked can destabilise the Mercier criterion in this type of configuration. We will show here that if the applied currents are hollow, they can stabilise the ballooning modes without triggering Mercier instabilities and as a result raise the limiting {beta}* from 2% to 5%. (author) 3 figs., 10 refs.

  4. Real-time volumetric visualization of high-resolution array and toroidal volume search sonar data

    Science.gov (United States)

    Cross, Robert A.

    1998-09-01

    The Advanced Volume Visualization Display (AVVD) research program is a joint research program between the Fraunhofer Center for Research in Computer Graphics, Inc. and Innovative Research and Development Corp. It is dedicated the application of the human visual system to real-time visualization of high- resolution volumetric sensor data sets. The AVVD program has successfully demonstrated its application to undersea imaging using data from the Naval Undersea Warfare Center -- Division Newport's High Resolution Array (HRA), and from the Naval Surface Warfare Center -- Coastal System Stations's Toroidal Volume Search Sonar (TVSS).

  5. Static envelope patterns in composite resonances generated by level crossing in optical toroidal microcavities.

    Science.gov (United States)

    Carmon, Tal; Schwefel, Harald G L; Yang, Lan; Oxborrow, Mark; Stone, A Douglas; Vahala, Kerry J

    2008-03-14

    We study level crossing in the optical whispering-gallery (WG) modes by using toroidal microcavities. Experimentally, we image the stationary envelope patterns of the composite optical modes that arise when WG modes of different wavelengths coincide in frequency. Numerically, we calculate crossings of levels that correspond with the observed degenerate modes, where our method takes into account the not perfectly transverse nature of their field polarizations. In addition, we analyze anticrossing with a large avoidance gap between modes of the same azimuthal number.

  6. External kinks in plasmas with helical boundary deformation and net toroidal current

    Energy Technology Data Exchange (ETDEWEB)

    Ardelea, A. [Ecole Polytechnique Federale, Lausanne (Switzerland). Centre de Recherche en Physique des Plasma (CRPP)

    1997-11-01

    The investigation of the global ideal magnetohydrodynamic (MHD) stability of plasmas with helical boundary shape and nonvanishing toroidal plasma current constitutes the principal aim of this work. Global external modes with small values of m,n (typically n = 1,2,3 and m = n+1) are studied, where m and n are the poloidal and toroidal mode numbers, respectively. The first and main part of the work concentrates on fixed boundary equilibria generated by systematically varying parameters such as the type and the magnitude of the boundary deformation, the number of equilibrium field periods N{sub per}, the aspect ratio, the toroidal current density profile, {beta} and the pressure profile. Due to the periodicity of the equilibrium, couplings between Fourier perturbation components with different toroidal mode numbers n occur and lead to the apparition of families of modes. The study of a particular (m,n) mode has to take into account all (m{sub l}, n{sub l}) perturbation components with n{sub 1} belonging to the same family as n. The stability analysis is carried out in the parameter region where the inverse rotational transform (the safety factor in the traditional tokamak notation) q{<=}2.0 and {beta}{<=}2%. A particular property of the configurations investigated is that equilibrium Fourier components (m{sub e}, N{sub per}n{sub e}) which are involved in the couplings between the (m,n) mode studied and the (m{sub k},n{sub k}) perturbation components with m{sub k}>n{sub k}>n that exhibit resonances in the q>1 region are very small. As a consequence, the contributions of the (m,n)x(m{sub k},n{sub k}) couplings to the potential energy are very weak. It is shown that a helical boundary deformation can stabilize the n=1,2,3 external modes; if {delta} is a measure of the plasma boundary deformation, then windows of stability [{delta}{sub min}, {delta}{sub max}] may exist for a large variety of equilibrium parameters. (author) figs., tabs., 44 refs.

  7. Zonal flow driven by energetic particle during magneto-hydro-dynamic burst in a toroidal plasma

    Science.gov (United States)

    Ohshima, S.; Fujisawa, A.; Shimizu, A.; Nakano, H.; Iguchi, H.; Yoshimura, Y.; Nagaoka, K.; Minami, T.; Isobe, M.; Nishimura, S.; Suzuki, C.; Akiyama, T.; Takahashi, C.; Takeuchi, M.; Ito, T.; Watari, T.; Kumazawa, R.; Itoh, S.-I.; Itoh, K.; Matsuoka, K.; Okamura, S.

    2007-11-01

    The internal structural measurements of electric field and density using twin heavy ion beam probes have been performed to elucidate the nonlinear evolution of the magneto-hydro-dynamic (MHD) bursty phenomenon driven by the interaction with high-energy particles in a toroidal plasma. The results have given the finest observation of the internal structure of plasma quantities, such as electric field, density and magnetic field distortion, which nonlinearly develop during the MHD phenomenon. In particular, the finding of a new kind of oscillating zonal flow driven by interaction between energetic particles and MHD modes should be emphasized for burning state plasmas.

  8. Controlling Confinement with Induced Toroidal Current in the Flexible Heliac TJ-II

    Energy Technology Data Exchange (ETDEWEB)

    Romero, J. A.; Lopez-Bruna, D.; Lopez-Fraguas, A.; Ascasibar, E.; TJ-II Team

    2002-07-01

    A method to control plasma particle an energy confinement in the TJ-II Heliac devices is reported A small toroidal current is induced in the plasma with the aid of a 0.2 Wb air core transformer. Plasma particle and energy confinement improve (degrade) with negative (positive) plasma current. For typical TJ-II discharges plasma density and temperature broaden considerably when plasma current is sufficiently negative, accounting for a 40% increase in stored energy. The experimental results agree qualitatively with the paradigm of instability growth rate modifications with magnetic shear. (Author) 18 refs.

  9. A Toroidally Symmetric Plasma Simulation code for design of position and shape control on tokamak plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Takase, Haruhiko [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Senda, Ikuo

    1999-04-01

    A Toroidally Symmetric Plasma Simulation (TSPS) code has been developed for investigating the position and shape control on tokamak plasmas. The analyses of three-dimensional eddy currents on the conducting components around the plasma and the two-dimensional magneto-hydrodynamic (MHD) equilibrium are taken into account in this code. The code can analyze the plasma position and shape control during the minor disruption in which the deformation of plasma is not negligible. Using the ITER (International Thermonuclear Experimental Reactor) parameters, some examples of calculations are shown in this paper. (author)

  10. The attenuation of Love waves and toroidal oscillations of the earth.

    Science.gov (United States)

    Jackson, D. D.

    1971-01-01

    An attempt has been made to invert a large set of attenuation data for Love waves and toroidal oscillations in the earth, using a recent method by Backus and Gilbert. The difficulty in finding an acceptable model of internal friction which explains the data, under the assumption that the internal friction is independent of frequency, casts doubt on the validity of this assumption. A frequency-dependent model of internal friction is presented which is in good agreement with the seismic data and with recent experimental measurements of attenuation in rocks.

  11. Installation of the LHC transfer lines begins

    CERN Multimedia

    Patrice Loïez

    2003-01-01

    The first of 700 magnets has been installed in one of the two transfer tunnels built to transfer the SPS beam into the LHC. The start of this first installation phase of the LHC transfer lines provides the opportunity to launch a new and highly original modular system for transporting and installing all kinds of magnets in very narrow tunnels. The system is based on very compact bogies, up to four of which can be coupled together to form a convoy. The wheels are fitted with individual motors enabling them to swivel through an angle of 90° and the convoy to move laterally. The first installation phase will continue until mid-April. In addition to the magnets, a beam dump facility also has to be installed. The second installation phase will take place later this year and should be completed in 2004, when the TI 8 transfer line is due to be tested. The second transfer line, in tunnel TI 2, should be ready in April 2007, once the LHC magnets have been transported through the downstream section of this tunnel. We...

  12. Installation of the LHC transfer lines begins

    CERN Multimedia

    Patrice Loïez

    2003-01-01

    The first of 700 magnets has been installed in one of the two transfer tunnels built to transfer the SPS beam into the LHC. The start of this first installation phase of the LHC transfer lines provides the opportunity to launch a new and highly original modular system for transporting and installing all kinds of magnets in very narrow tunnels. The system is based on very compact bogies, up to four of which can be coupled together to form a convoy. The wheels are fitted with individual motors enabling them to swivel through an angle of 90° and the convoy to move laterally. The first installation phase will continue until mid-April. In addition to the magnets, a beam dump facility also has to be installed. The second installation phase will take place later this year and should be completed in 2004, when the TI 8 transfer line is due to be tested. The second transfer line, in tunnel TI 2, should be ready in April 2007, once the LHC magnets have been transported through the downstream section of this tunnel. Th...

  13. Installation of the LHC transfer lines begins

    CERN Multimedia

    Patrice Loïez

    2003-01-01

    The first of 700 magnets has been installed in one of the two transfer tunnels built to transfer the SPS beam into the LHC. The start of this first installation phase of the LHC transfer lines provides the opportunity to launch a new and highly original modular system for transporting and installing all kinds of magnets in very narrow tunnels. The system is based on very compact bogies, up to four of which can be coupled together to form a convoy. The wheels are fitted with individual motors enabling them to swivel through an angle of 90° and the convoy to move laterally. The first installation phase will continue until mid-April. In addition to the magnets, a beam dump facility also has to be installed. The second installation phase will take place later this year and should be completed in 2004, when the TI 8 transfer line is due to be tested. The second transfer line, in tunnel TI 2, should be ready in April 2007, once the LHC magnets have been transported through the downstream section of this tunnel.Pho...

  14. Comparative analysis of the Tyr-kinases CapB1 and CapB2 fused to their cognate modulators CapA1 and CapA2 from Staphylococcus aureus.

    Directory of Open Access Journals (Sweden)

    Jakub Gruszczyk

    Full Text Available A particular class of tyrosine-kinases sharing no structural similarity with eukaryotic tyrosine-kinases has been evidenced in a large array of bacterial species. These bacterial tyrosine-kinases are able to autophosphorylate on a C-terminal tyrosine-rich motif. Their autophosphorylation has been shown to play a crucial role in the biosynthesis or export of capsular polysaccharide. The analysis of the first crystal structure of the staphylococcal tyrosine kinase CapB2 associated with the activating domain of the transmembrane modulator CapA1 had brought conclusive explanation for both the autophosphorylation and activation processes. In order to explain why CapA1 activates CapB2 more efficiently than its cognate transmembrane modulator CapA2, we solved the crystal structure of CapA2B2 and compared it with the previously published structure of CapA1B2. This structural analysis did not provide the expected clues about the activation discrepancy observed between the two modulators. Staphylococcus aureus also encodes for a CapB2 homologue named CapB1 displaying more than 70% sequence similarity and being surprisingly nearly unable to autophosphorylate. We solved the crystal structure of CapA1B1 and carefully compare it with the structure of CapA1B2. The active sites of both proteins are highly conserved and the biochemical characterization of mutant proteins engineered to test the importance of small structural discrepancies identified between the two structures did not explain the inactivity of CapB1. We thus tested if CapB1 could phosphorylate other protein substrates or hydrolyze ATP. However, no activity could be detected in our in vitro assays. Taken together, these data question about the biological role of the homologous protein pairs CapA1/CapB1 and CapA2/CapB2 and we discuss about several possible interpretations.

  15. Macrophage Capping Protein CapG Is a Putative Oncogene Involved in Migration and Invasiveness in Ovarian Carcinoma

    Directory of Open Access Journals (Sweden)

    J. Glaser

    2014-01-01

    Full Text Available The actin binding protein CapG modulates cell motility by interacting with the cytoskeleton. CapG is associated with tumor progression in different nongynecologic tumor entities and overexpression in breast cancer cell lines correlates with a more invasive phenotype in vitro. Here, we report a significant CapG overexpression in 18/47 (38% of ovarian carcinomas (OC analyzed by qRealTime-PCR analyses. Functional analyses in OC cell lines through siRNA mediated CapG knockdown and CapG overexpression showed CapG-dependent cell migration and invasiveness. A single nucleotide polymorphism rs6886 inside the CapG gene was identified, affecting a CapG phosphorylation site and thus potentially modifying CapG function. The minor allele frequency (MAF of SNP rs6886 (c.1004A/G was higher and the homozygous (A/A, His335 genotype was significantly more prevalent in patients with fallopian tube carcinomas (50% as in controls (10%. With OC being one of the most lethal cancer diseases, the detection of novel biomarkers such as CapG could reveal new diagnostic and therapeutic targets. Moreover, in-depth analyses of SNP rs6886 related to FTC and OC will contribute to a better understanding of carcinogenesis and progression of OC.

  16. Sediment Capping and Natural Recovery, Contaminant Transport Fundamentals With Applications to Sediment Caps

    Science.gov (United States)

    2005-09-01

    source concentration through time are often represented as first-order (exponential) decay processes and can be described by the equation t ot eCC λ...meter. This coupled with the relative homo - geneity of many capping materials should in most settings cause the effects asso- ciated with

  17. Incorporating Wind Generation in Cap and Trade Programs

    Energy Technology Data Exchange (ETDEWEB)

    Bluestein, J.; Salerno, E.; Bird, L.; Vimmerstedt, L.

    2006-07-01

    Cap and trade programs are increasingly being used to reduce emissions from electricity generation in the United States. Cap and trade programs primarily target emitting generators, but programs have also included renewable generators, such as wind generators. States cite several reasons why they have considered the policy option of including renewable generators in cap and trade programs: to provide an incentive for lower-emitting generation, to achieve emissions reductions in non-capped pollutants, and to gain local economic benefits associated with renewable energy projects. The U.S. Environmental Protection Agency also notes these rationales for considering this policy alternative, and the National Association of Regulatory Commissioners (NARUC) passed a resolution supporting the inclusion of renewable energy in cap and trade programs. This report explores why states consider this policy option, what participation could mean for wind generators, and how wind generation can most effectively be included in state, federal, and regional cap and trade programs.

  18. Procalcitonin and community-acquired pneumonia (CAP) in children.

    Science.gov (United States)

    Giulia, Bivona; Luisa, Agnello; Concetta, Scazzone; Bruna, Lo Sasso; Chiara, Bellia; Marcello, Ciaccio

    2015-12-07

    The role of procalcitonin (PCT) as a biomarker for sepsis in adults is well documented, while its role in infections affecting neonatal children remains controversial. Among these infections, Community-Acquired pneumonia (CAP) has been studied extensively, because it's the second cause of death in children in developing countries, and one of the most frequent causes of hospitalization in industrialized countries. The PubMed database and the Cochrane Library were used to search for the following keywords: CAP, procalcitonin, and children. Thirteen articles were studied to determine the role of PCT in CAP management, specifically its usefulness for distinguishing pneumococcal infections from viral and unknown infections, for predicting severity and the correct antibiotic treatment. This paper focuses on the studies performed to identify the best inflammatory biomarker for CAP management. Although there is an increase in studies confirming the usefulness of PCT in CAP management in children, further studies are needed to have better understanding of its role for pediatric CAP management.

  19. Arrays of magnetic nanoparticles capped with alkylamines

    Indian Academy of Sciences (India)

    P John Thomas; P Saravanan; G U Kulkarni; C N R Rao

    2002-02-01

    Magnetic metal and metal oxide nanoparticles capped with alkylamines have been synthesized and characterized by transmission electron microscopy, X-ray diffraction, energy dispersive X-ray analysis and magnetization measurements. Core-shell Pd–Ni particles with composition, Pd561Ni3000, (diameter ∼ 3.3 nm) are superparamagnetic at 5 K and organize themselves into two-dimensional crystalline arrays. Similar arrays are obtained with Pd561Ni3000Pd1500 nanoparticles containing an additional Pd shell. Magnetic spinel particles of -Fe2O3, Fe3O4 and CoFe2O4 of average diameters in the 4–6 nm range coated with octylamine are all supermagnetic at room temperature and yield close-packed disordered arrays. Relatively regular arrays are formed by dodecylamine-capped Fe3O4 nanoparticles (∼ 8.6 nm diameter) while well-ordered hexagonal arrays were obtained with octylamine-covered Co3O4 nanoparticles (∼ 4.2 nm diameter).

  20. Comparison of Polar Cap (PC) index calculations.

    Science.gov (United States)

    Stauning, P.

    2012-04-01

    The Polar Cap (PC) index introduced by Troshichev and Andrezen (1985) is derived from polar magnetic variations and is mainly a measure of the intensity of the transpolar ionospheric currents. These currents relate to the polar cap antisunward ionospheric plasma convection driven by the dawn-dusk electric field, which in turn is generated by the interaction of the solar wind with the Earth's magnetosphere. Coefficients to calculate PCN and PCS index values from polar magnetic variations recorded at Thule and Vostok, respectively, have been derived by several different procedures in the past. The first published set of coefficients for Thule was derived by Vennerstrøm, 1991 and is still in use for calculations of PCN index values by DTU Space. Errors in the program used to calculate index values were corrected in 1999 and again in 2001. In 2005 DMI adopted a unified procedure proposed by Troshichev for calculations of the PCN index. Thus there exists 4 different series of PCN index values. Similarly, at AARI three different sets of coefficients have been used to calculate PCS indices in the past. The presentation discusses the principal differences between the various PC index procedures and provides comparisons between index values derived from the same magnetic data sets using the different procedures. Examples from published papers are examined to illustrate the differences.