WorldWideScience

Sample records for machines axial gap

  1. Axial gap rotating electrical machine

    Science.gov (United States)

    None

    2016-02-23

    Direct drive rotating electrical machines with axial air gaps are disclosed. In these machines, a rotor ring and stator ring define an axial air gap between them. Sets of gap-maintaining rolling supports bear between the rotor ring and the stator ring at their peripheries to maintain the axial air gap. Also disclosed are wind turbines using these generators, and structures and methods for mounting direct drive rotating electrical generators to the hubs of wind turbines. In particular, the rotor ring of the generator may be carried directly by the hub of a wind turbine to rotate relative to a shaft without being mounted directly to the shaft.

  2. Melt-growth bulk superconductors and application to an axial-gap-type rotating machine

    International Nuclear Information System (INIS)

    Zhang, Yufeng; Zhou, Difan; Ida, Tetsuya; Miki, Motohiro; Izumi, Mitsuru

    2016-01-01

    The present manuscript addresses key issues in the course of our study of materials processing of bulk high-temperature superconductors, trapped flux and its application to a prototype axial-gap-type rotating machine. The TUMSAT group has conducted a series of studies since 2003 on the growth of GdBa 2 Cu 3 O 7−δ bulk material and its application in a compact low-speed high-torque rotating machine. In the stage of material growth, gaining the advantage of a large motive torque density requires large integrated flux in the motor/generators. A large grain surface might be required with sophisticated techniques for the melt-growth texture in the bulk with optimal flux pinning. In the second stage, the in situ magnetization procedure for bulk superconductors in the applied machine is a crucial part of the technology. Pulsed current excitation by using an armature copper winding has magnetized field pole bulks on the rotor. The axial-gap flux synchronous machine studied in the past decade is a condensed technology and indicates that further scientific development is required for a future compact machine to be superior to conventional ones in accordance with the cryogenic periphery and flux stabilization. (paper)

  3. Single pulsed-field magnetization on Gd-Ba-Cu-O Bulk HTS assembled for axial-gap type rotating machines

    International Nuclear Information System (INIS)

    Morita, E; Matsuzaki, H; Kimura, Y; Ohtani, I; Izumi, M; Nonaka, Y; Murakami, M; Ida, T; Sugimoto, H; Miki, M; Kitano, M

    2006-01-01

    We employed Gd-bulk HTS magnets as rotating poles for a smaller and lighter axial-gap type rotating machine. The bulk was placed between two vortex-type armature coils and cooled down to 77 K under zero-field. Pulsed current was applied to the vortex-type magnetizing coils. The trapped field distribution and transient flux behaviour strongly depend on the radial dimension of the armature vortex-type coil. In the present study, we show that there is an optimal radial dimension of magnetizing coils to the given bulk disk size to give a homogeneously conical distribution of the trapped flux

  4. Electric machines with axial magnetic flux

    Science.gov (United States)

    Nuca, I.; Ambros, T.; Burduniuc, M.; Deaconu, S. I.; Turcanu, A.

    2018-01-01

    The paper contains information on the performance of axial machines compared to cylindrical ones. At the same time, various constructive schemes of synchronous electromechanical converters with permanent magnets and asynchronous with short-circuited rotor are presented. In the developed constructions, the aim is to maximize the usage of the material of the stator windings. The design elements of the axial machine magnetic system are presented. The FEMM application depicted the array of the magnetic field of an axial machine.

  5. Axial flux permanent magnet brushless machines

    CERN Document Server

    Gieras, Jacek F; Kamper, Maarten J

    2008-01-01

    Axial Flux Permanent Magnet (AFPM) brushless machines are modern electrical machines with a lot of advantages over their conventional counterparts. They are being increasingly used in consumer electronics, public life, instrumentation and automation system, clinical engineering, industrial electromechanical drives, automobile manufacturing industry, electric and hybrid electric vehicles, marine vessels and toys. They are also used in more electric aircrafts and many other applications on larger scale. New applications have also emerged in distributed generation systems (wind turbine generators

  6. Research on a novel axial-flux magnetic-field-modulated brushless double-rotor machine with low axial force and high efficiency

    Directory of Open Access Journals (Sweden)

    Chengde Tong

    2017-05-01

    Full Text Available The axial-flux magnetic-field-modulated brushless double-rotor machine (MFM-BDRM is a possible alternative as a power-split device for hybrid electric vehicles (HEVs. However, the existence of large axial force may lead to assembly problems and rich inner air-gap harmonics could result in high PM loss and low efficiency. This paper proposes a novel axial-flux MFM-BDRM with improved PM rotor structure. 2-D analytical method to predict the magnetic-field distribution of the proposed MFM-BDRM is developed and the design procedure of the proposed machine is illustrated. The impact of key geometrical parameters on axial force and torque is investigated. To evaluate the advantage of the proposed machine, a comparison is made with a conventional one with respect to electromagnetic performances. Results show that the proposed machine is effective in reducing PM eddy loss and axial force by 60% and 35%, respectively.

  7. Redesigning axial-axial (biaxial) cruciform specimens for very high cycle fatigue ultrasonic testing machines.

    Science.gov (United States)

    Montalvão, Diogo; Wren, Andrew

    2017-11-01

    The necessity to increase performances in terms of lifetime and security in mechanical components or structures is the motivation for intense research in fatigue. Applications range from aeronautics to medical devices. With the development of new materials, there is no longer a fatigue limit in the classical sense, where it was accepted that the fatigue limit is the stress level such that there is no fracture up to 1E7 cycles. The recent development of ultrasonic testing machines where frequencies can go as high as 20 kHz or over enabled tests to be extended to ranges larger than 1E9 in just a few days. This area of studies is now known as Very High Cycle Fatigue (VHCF). On the other hand, most of the existing test equipment in the market for both classical and VHCF are uniaxial test machines. However, critical components used in Engineering applications are usually subjected to complex multi-axial loading conditions. In this paper, it is presented the methodology to redesigning existing cruciform test specimens that can be used to create an in-plane biaxial state of stress when used in 'uniaxial' VHCF ultrasonic testing machines (in this case, the term 'uniaxial' is used not because of the state of stress created at the centre of the specimen, but because of the direction at which the load is applied). The methodology is explained in such a way that it can be expanded to other existing designs, namely cruciform designs, that are not yet used in VHCF. Also, although the approach is presented in simple and logical terms, it may not be that obvious for those who have a more focused approach on fatigue rather than on modal analysis. It is expected that by contributing to bridging the gap between the sciences of modal analysis and fatigue, this research will help and encourage others exploiting new capabilities in VHCF.

  8. Trunnion Collar Removal Machine - Gap Analysis Table

    International Nuclear Information System (INIS)

    Johnson, M.

    2005-01-01

    The purpose of this document is to review the existing the trunnion collar removal machine against the ''Nuclear Safety Design Bases for License Application'' (NSDB) [Ref. 10] requirements and to identify codes and standards and supplemental requirements to meet these requirements. If these codes and standards can not fully meet these requirements then a ''gap'' is identified. These gaps will be identified here and addressed using the ''Trunnion Collar Removal Machine Design Development Plan'' [Ref. 15]. The codes and standards, supplemental requirements, and design development requirements for the trunnion collar removal machine are provided in the gap analysis table (Appendix A, Table 1). Because the trunnion collar removal machine is credited with performing functions important to safety (ITS) in the NSDB [Ref. 10], design basis requirements are applicable to ensure equipment is available and performs required safety functions when needed. The gap analysis table is used to identify design objectives and provide a means to satisfy safety requirements. To ensure that the trunnion collar removal machine performs required safety functions and meets performance criteria, this portion of the gap analysis tables supplies codes and standards sections and the supplemental requirements and identifies design development requirements, if needed

  9. Axial gap formation in P.W.R. fuel pins

    International Nuclear Information System (INIS)

    Roberts, G.; Jones, K.W.

    1978-07-01

    The potential mechanisms of axial gap formation in PWR fuel pins are examined analytically and also using evidence from post-irradiation examination (p.i.e.) investigation. It is concluded that fuel and cladding cannot remain in contact during densification and so the settling of of the fuel stack, which forms the gaps, must be prevented by such things as asperities in the cladding, fuel chips or tilted pellets. Examples from the p.i.e. examination programme are used to support this conclusion. (author)

  10. An Axial Sliding Test for machine elements surfaces

    DEFF Research Database (Denmark)

    Godi, Alessandro; Grønbæk, J.; Mohaghegh, Kamran

    2012-01-01

    are necessary: a press to provide the normal pressure and a tensile machine to perform the axial movements. The test is calibrated so that the correspondence between the normal pressure and the container advancement is found. Finally, preliminary tests are carried out involving a multifunctional and a fine......Throughout the years, it has become more and more important to find new methods for reducing friction and wear occurrence in machine elements. A possible solution is found in texturing the surfaces under tribological contact, hence the development and spread of plateau-honed surface for cylinder...... liners. To prove the efficacy of a particular textured surface, it is paramount to perform experimental tests under controlled laboratory conditions. In this paper a new test rig simulating pure sliding conditions is presented, dubbed Axial Sliding Test. It presents four major components: a rod, a sleeve...

  11. Study of axial protections of unloading machines of graphite piles

    International Nuclear Information System (INIS)

    Duco, Jacques; Pepin, Pierre; Cabaret, Guy; Dubor, Monique

    1969-10-01

    As previous studies resulted in the development of a simple calculation formula based on experimental results for the calculation of neutron protection thicknesses for loading machines, this study aimed at determining axial protections of these machines which represent a specific problem: scattering of delayed neutrons in the machine inner cavity may result in an important neutron leakage through the upper part, at the level of the winch enclosure. In an experimental part, this study comprises the measurement of the neutron dose in a 2.60 m long and 54 cm diameter cylindrical cavity, and in the thickness of the surrounding concrete protection. In the second part, the authors present a calculation method which uses the Zeus and Mercure codes to interpret the results [fr

  12. Mind the gap - tip leakage vortex in axial turbines

    International Nuclear Information System (INIS)

    Dreyer, M; Farhat, M; Decaix, J; Münch-Alligné, C

    2014-01-01

    The tendency of designing large Kaplan turbines with a continuous increase of output power is bringing to the front the cavitation erosion issue. Due to the flow in the gap between the runner and the discharge ring, axial turbine blades may develop the so called tip leakage vortex (TLV) cavitation with negative consequences. Such vortices may interact strongly with the wake of guide vanes leading to their multiple collapses and rebounds. If the vortex trajectory remains close to the blade tip, these collapses may lead to severe erosion. One is still unable today to predict its occurrence and development in axial turbines with acceptable accuracy. Numerical flow simulations as well as the actual scale-up rules from small to large scales are unreliable. The present work addresses this problematic in a simplified case study representing TLV cavitation to better understand its sensitivity to the gap width. A Naca0009 hydrofoil is used as a generic blade in the test section of EPFL cavitation tunnel. A sliding mounting support allowing an adjustable gap between the blade tip and wall was manufactured. The vortex trajectory is visualized with a high speed camera and appropriate lighting. The three dimensional velocity field induced by the TLV is investigated using stereo particle image velocimetry. We have taken into account the vortex wandering in the image processing to obtain accurate measurements of the vortex properties. The measurements were performed in three planes located downstream of the hydrofoil for different values of the flow velocity, the incidence angle and the gap width. The results clearly reveal a strong influence of the gap width on both trajectory and intensity of the tip leakage vortex

  13. Mind the gap - tip leakage vortex in axial turbines

    Science.gov (United States)

    Dreyer, M.; Decaix, J.; Münch-Alligné, C.; Farhat, M.

    2014-03-01

    The tendency of designing large Kaplan turbines with a continuous increase of output power is bringing to the front the cavitation erosion issue. Due to the flow in the gap between the runner and the discharge ring, axial turbine blades may develop the so called tip leakage vortex (TLV) cavitation with negative consequences. Such vortices may interact strongly with the wake of guide vanes leading to their multiple collapses and rebounds. If the vortex trajectory remains close to the blade tip, these collapses may lead to severe erosion. One is still unable today to predict its occurrence and development in axial turbines with acceptable accuracy. Numerical flow simulations as well as the actual scale-up rules from small to large scales are unreliable. The present work addresses this problematic in a simplified case study representing TLV cavitation to better understand its sensitivity to the gap width. A Naca0009 hydrofoil is used as a generic blade in the test section of EPFL cavitation tunnel. A sliding mounting support allowing an adjustable gap between the blade tip and wall was manufactured. The vortex trajectory is visualized with a high speed camera and appropriate lighting. The three dimensional velocity field induced by the TLV is investigated using stereo particle image velocimetry. We have taken into account the vortex wandering in the image processing to obtain accurate measurements of the vortex properties. The measurements were performed in three planes located downstream of the hydrofoil for different values of the flow velocity, the incidence angle and the gap width. The results clearly reveal a strong influence of the gap width on both trajectory and intensity of the tip leakage vortex.

  14. FEM analysis of an single stator dual PM rotors axial synchronous machine

    Science.gov (United States)

    Tutelea, L. N.; Deaconu, S. I.; Popa, G. N.

    2017-01-01

    The actual e - continuously variable transmission (e-CVT) solution for the parallel Hybrid Electric Vehicle (HEV) requires two electric machines, two inverters, and a planetary gear. A distinct electric generator and a propulsion electric motor, both with full power converters, are typical for a series HEV. In an effort to simplify the planetary-geared e-CVT for the parallel HEV or the series HEV we hereby propose to replace the basically two electric machines and their two power converters by a single, axial-air-gap, electric machine central stator, fed from a single PWM converter with dual frequency voltage output and two independent PM rotors. The proposed topologies, the magneto-motive force analysis and quasi 3D-FEM analysis are the core of the paper.

  15. Launch Lock Assemblies Including Axial Gap Amplification Devices and Spacecraft Isolation Systems Including the Same

    Science.gov (United States)

    Barber, Tim Daniel (Inventor); Hindle, Timothy (Inventor); Young, Ken (Inventor); Davis, Torey (Inventor)

    2014-01-01

    Embodiments of a launch lock assembly are provided, as are embodiments of a spacecraft isolation system including one or more launch lock assemblies. In one embodiment, the launch lock assembly includes first and second mount pieces, a releasable clamp device, and an axial gap amplification device. The releasable clamp device normally maintains the first and second mount pieces in clamped engagement; and, when actuated, releases the first and second mount pieces from clamped engagement to allow relative axial motion there between. The axial gap amplification device normally residing in a blocking position wherein the gap amplification device obstructs relative axial motion between the first and second mount pieces. The axial gap amplification device moves into a non-blocking position when the first and second mount pieces are released from clamped engagement to increase the range of axial motion between the first and second mount pieces.

  16. A single-phase axially-magnetized permanent-magnet oscillating machine for miniature aerospace power sources

    Directory of Open Access Journals (Sweden)

    Yi Sui

    2017-05-01

    Full Text Available A single-phase axially-magnetized permanent-magnet (PM oscillating machine which can be integrated with a free-piston Stirling engine to generate electric power, is investigated for miniature aerospace power sources. Machine structure, operating principle and detent force characteristic are elaborately studied. With the sinusoidal speed characteristic of the mover considered, the proposed machine is designed by 2D finite-element analysis (FEA, and some main structural parameters such as air gap diameter, dimensions of PMs, pole pitches of both stator and mover, and the pole-pitch combinations, etc., are optimized to improve both the power density and force capability. Compared with the three-phase PM linear machines, the proposed single-phase machine features less PM use, simple control and low controller cost. The power density of the proposed machine is higher than that of the three-phase radially-magnetized PM linear machine, but lower than the three-phase axially-magnetized PM linear machine.

  17. A single-phase axially-magnetized permanent-magnet oscillating machine for miniature aerospace power sources

    Science.gov (United States)

    Sui, Yi; Zheng, Ping; Cheng, Luming; Wang, Weinan; Liu, Jiaqi

    2017-05-01

    A single-phase axially-magnetized permanent-magnet (PM) oscillating machine which can be integrated with a free-piston Stirling engine to generate electric power, is investigated for miniature aerospace power sources. Machine structure, operating principle and detent force characteristic are elaborately studied. With the sinusoidal speed characteristic of the mover considered, the proposed machine is designed by 2D finite-element analysis (FEA), and some main structural parameters such as air gap diameter, dimensions of PMs, pole pitches of both stator and mover, and the pole-pitch combinations, etc., are optimized to improve both the power density and force capability. Compared with the three-phase PM linear machines, the proposed single-phase machine features less PM use, simple control and low controller cost. The power density of the proposed machine is higher than that of the three-phase radially-magnetized PM linear machine, but lower than the three-phase axially-magnetized PM linear machine.

  18. Permanent magnet machines with air gap windings and integrated teeth windings

    Energy Technology Data Exchange (ETDEWEB)

    Alatalo, M [Chalmers Univ. of Technology, Goeteborg (Sweden). School of Electrical and Computer Engineering

    1996-06-01

    The Thesis deals with axial and radial flux permanent magnet machines with air gap windings and an integrated teeth winding. The aim is to develop a machine that produces a high torque per unit volume with as low losses as possible. The hypothesis is that an advanced three-phase winding, magnetized by a permanent magnet rotor should be better than other machine topologies. The finite element method is used to find favourable dimensions of the slotless winding, the integrated teeth winding and the permanent magnet rotor. Three machines were built and tested in order to verify calculations. It can be concluded that the analysis method shows good agreement with the calculated and the measured values of induced voltage and torque. The experiments showed that the slotless machine with NdFeB-magnets performs approximately like the slotted machine. A theoretical comparison of axial flux topology to radial flux topology showed that the torque production of the inner rotor radial flux machine is superior to that of the axial flux machine. An integrated teeth winding based on iron powder teeth glued to the winding was studied. The force density of a pole with integrated teeth is around three times the force density of a slotless pole. A direct drive wind power generator of 6.4 kW with integrated teeth can have the same power losses and magnet weight as a transversal flux machine. Compared to a standard induction machine the integrated teeth machine had approximately 2.5 times the power capacity of the induction machine with the same power losses and outer volume. 39 refs

  19. A tubular hybrid Halbach/axially-magnetized permanent-magnet linear machine

    Directory of Open Access Journals (Sweden)

    Yi Sui

    2017-05-01

    Full Text Available A single-phase tubular permanent-magnet linear machine (PMLM with hybrid Halbach/axially-magnetized PM arrays is proposed for free-piston Stirling power generation system. Machine topology and operating principle are elaborately illustrated. With the sinusoidal speed characteristic of the free-piston Stirling engine considered, the proposed machine is designed and calculated by finite-element analysis (FEA. The main structural parameters, such as outer radius of the mover, radial length of both the axially-magnetized PMs and ferromagnetic poles, axial length of both the middle and end radially-magnetized PMs, etc., are optimized to improve both the force capability and power density. Compared with the conventional PMLMs, the proposed machine features high mass and volume power density, and has the advantages of simple control and low converter cost. The proposed machine topology is applicable to tubular PMLMs with any phases.

  20. A tubular hybrid Halbach/axially-magnetized permanent-magnet linear machine

    Science.gov (United States)

    Sui, Yi; Liu, Yong; Cheng, Luming; Liu, Jiaqi; Zheng, Ping

    2017-05-01

    A single-phase tubular permanent-magnet linear machine (PMLM) with hybrid Halbach/axially-magnetized PM arrays is proposed for free-piston Stirling power generation system. Machine topology and operating principle are elaborately illustrated. With the sinusoidal speed characteristic of the free-piston Stirling engine considered, the proposed machine is designed and calculated by finite-element analysis (FEA). The main structural parameters, such as outer radius of the mover, radial length of both the axially-magnetized PMs and ferromagnetic poles, axial length of both the middle and end radially-magnetized PMs, etc., are optimized to improve both the force capability and power density. Compared with the conventional PMLMs, the proposed machine features high mass and volume power density, and has the advantages of simple control and low converter cost. The proposed machine topology is applicable to tubular PMLMs with any phases.

  1. Dual rotor single- stator axial air gap PMSM motor/generator drive for high torque vehicles applications

    International Nuclear Information System (INIS)

    University of Timisoara, Electrical Engineering Department, Vasile Parvan str., no. 1-2, 300223 Timisoara (Romania))" data-affiliation=" (Politehnica University of Timisoara, Electrical Engineering Department, Vasile Parvan str., no. 1-2, 300223 Timisoara (Romania))" >Tutelea, L N; University of Timisoara, Electrical Engineering Department, Vasile Parvan str., no. 1-2, 300223 Timisoara (Romania))" data-affiliation=" (Politehnica University of Timisoara, Electrical Engineering Department, Vasile Parvan str., no. 1-2, 300223 Timisoara (Romania))" >Boldea, I; University of Timisoara, Department of Electrotechnical Engineering and Industrial Informatics, 5 Revolution Street, Hunedoara, 331128 (Romania))" data-affiliation=" (Politehnica University of Timisoara, Department of Electrotechnical Engineering and Industrial Informatics, 5 Revolution Street, Hunedoara, 331128 (Romania))" >Deaconu, S I; University of Timisoara, Department of Electrotechnical Engineering and Industrial Informatics, 5 Revolution Street, Hunedoara, 331128 (Romania))" data-affiliation=" (Politehnica University of Timisoara, Department of Electrotechnical Engineering and Industrial Informatics, 5 Revolution Street, Hunedoara, 331128 (Romania))" >Popa, G N

    2014-01-01

    The actual e – continuously variable transmission (e-CVT) solution for the parallel Hybrid Electric Vehicle (HEV) requires two electric machines, two inverters, and a planetary gear. A distinct electric generator and a propulsion electric motor, both with full power converters, are typical for a series HEV. In an effort to simplify the planetary-geared e-CVT for the parallel HEV or the series HEV we hereby propose to replace the basically two electric machines and their two power converters by a single, axial-air-gap, electric machine central stator, fed from a single PWM converter with dual frequency voltage output and two independent PM rotors, destined for hybrid electric vehicles (HEV) and military vehicles applications. The proposed topologies and the magneto-motive force analysis are the core of the paper

  2. Dual rotor single- stator axial air gap PMSM motor/generator drive for high torque vehicles applications

    Science.gov (United States)

    Tutelea, L. N.; Deaconu, S. I.; Boldea, I.; Popa, G. N.

    2014-03-01

    The actual e - continuously variable transmission (e-CVT) solution for the parallel Hybrid Electric Vehicle (HEV) requires two electric machines, two inverters, and a planetary gear. A distinct electric generator and a propulsion electric motor, both with full power converters, are typical for a series HEV. In an effort to simplify the planetary-geared e-CVT for the parallel HEV or the series HEV we hereby propose to replace the basically two electric machines and their two power converters by a single, axial-air-gap, electric machine central stator, fed from a single PWM converter with dual frequency voltage output and two independent PM rotors, destined for hybrid electric vehicles (HEV) and military vehicles applications. The proposed topologies and the magneto-motive force analysis are the core of the paper.

  3. Design of an axial-flux permanent magnet machine for a solar-powered electric vehicle

    NARCIS (Netherlands)

    Friedrich, L.A.J.; Bastiaens, K.; Gysen, B.L.J.; Krop, D.C.J.; Lomonova, E.A.

    2018-01-01

    This paper concerns the design optimization of two axial-flux permanent magnet (AFPM) machines, aimed to be used as a direct drive in-wheel motor for the propulsion of a solar-powered electric vehicle. The internal stator twin external rotor AFPM machine topology having either a distributed or

  4. Permanent-magnet-less machine having an enclosed air gap

    Science.gov (United States)

    Hsu, John S [Oak Ridge, TN

    2012-02-07

    A permanent magnet-less, brushless synchronous system includes a stator that generates a magnetic rotating field when sourced by an alternating current. An uncluttered rotor disposed within the magnetic rotating field is spaced apart from the stator to form an air gap relative to an axis of rotation. A stationary excitation core spaced apart from the uncluttered rotor by an axial air gap and a radial air gap substantially encloses the stationary excitation core. Some permanent magnet-less, brushless synchronous systems include stator core gaps to reduce axial flux flow. Some permanent magnet-less, brushless synchronous systems include an uncluttered rotor coupled to outer laminations. The quadrature-axis inductance may be increased in some synchronous systems. Some synchronous systems convert energy such as mechanical energy into electrical energy (e.g., a generator); other synchronous systems may convert any form of energy into mechanical energy (e.g., a motor).

  5. Design of a Modular E-Core Flux Concentrating Axial Flux Machine: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Husain, Tausif; Sozer, Yilmaz; Husain, Iqbal; Muljadi, Eduard

    2015-08-24

    In this paper a novel E-Core axial flux machine is proposed. The machine has a double-stator, single-rotor configuration with flux-concentrating ferrite magnets and pole windings across each leg of an E-Core stator. E-Core stators with the proposed flux-concentrating rotor arrangement result in better magnet utilization and higher torque density. The machine also has a modular structure facilitating simpler construction. This paper presents a single-phase and a three-phase version of the E-Core machine. Case studies for a 1.1-kW, 400-rpm machine for both the single-phase and three-phase axial flux machines are presented. The results are verified through 3D finite element analysis. facilitating simpler construction. This paper presents a single-phase and a three-phase version of the E-Core machine. Case studies for a 1.1-kW, 400-rpm machine for both the single-phase and three-phase axial flux machines are presented. The results are verified through 3D finite element analysis.

  6. Research on monitoring technology of axial gap change about high-speed rotating machinery

    International Nuclear Information System (INIS)

    Zhang Xiaochan; Liu Fanglei; Hu Shihua; Xie Qing; Li Zhen

    2014-01-01

    This paper describes that the only measuring point of high-speed rotating machinery (speed monitoring transducer) measuring the operation of the axial gap change and application. According to mechanism analysis the speed monitoring transducer's signal, prove its amplitude changes including the axial gap change information. To carry out the speed monitoring transducer qualitative and quantitative axial gap change research, Find the output signal amplitude and clearance change corresponding relationship formula of speed monitoring transducer, define the measurement method. Based on the above analsis, manufacture the single channel measurement devices and multiple unit measurement system, provide an important fault decision of high-speed rotating machinery, it can be applied to new equipment development and production. (authors)

  7. Optimization of electrical parameters of windings used in axial flux electrical machines

    International Nuclear Information System (INIS)

    Uhrik, M.

    2012-01-01

    This paper deals with shape optimization of windings used in electrical machines with disc type construction. These machines have short axial length what makes them suitable for use in small wind-power turbines or in-wheel traction drives. Disc type construction of stator offers more possibilities for winding arrangements than are available in classical machines with cylindrical construction. To find out the best winding arrangement for the novel disc type machine construction a series of analytical calculations, simulations and experimental measurements were performed. (Authors)

  8. Deformation and collapse of zircaloy fuel rod cladding into plenum axial gaps

    International Nuclear Information System (INIS)

    Pfennigwerth, P.L.; Gorscak, D.A.; Selsley, I.A.

    1983-01-01

    To minimize support structure, blanket and reflector fuel rods of the thoria urania-fueled Light Water Breeder Reactor (LWBR) were designed with non-freestanding Zircaloy-4 cladding. An analytical model was developed to predict deformation of unirradiated cladding into axial gaps of fuel rod plenum regions where it is unsupported. This model uses the ACCEPT finite element computer program to calculate elastic-plastic deformation of cladding due to external pressure. The finite element is 20-node, triquadratic, isoparametric, and 3-dimensional. Its curved surface permits accurate modeling of the tube geometry, including geometric nonuniformities such as circumferential wall thickness variation and initial tube out-of-roundness. Progressive increases in axial gap length due to cladding elongation and fuel stack shrinkage are modeled, as are deformations of fuel pellets and stainless steel support sleeves which bound plenum axial gaps in LWBR type blanket fuel rods. Zircaloy-4 primary and secondary thermal creep representations were developed from uniaxial creep testing of fuel rod tubing. Creep response to multi-axial loading is modeled with a variation of Hill's formulation for anisotropic materials. Coefficients accounting for anisotropic thermal creep in Zircaloy-4 tubes were developed from creep testing of externally pressurized tubes having fixed axial gaps in the range 2.5 cm to 5.7 cm and radial clearances over simulated fuel pellets ranging from zero to 0.089 mm. (orig./RW)

  9. An electrostatic lower stator axial gap wobble motor: design and fabrication

    NARCIS (Netherlands)

    Legtenberg, R.; Legtenberg, Rob; Berenschot, Johan W.; van Baar, J.J.J.; Lammerink, Theodorus S.J.; Elwenspoek, Michael Curt

    1995-01-01

    The fabrication, initial modelling and first results of an electrostatic lower stator axial gap wobble motor are presented. The four mask fabrication process is based on polysilicon surface micromachining techniques. Three to twelve stator pole wobble motor designs have been realized with rotor

  10. Design and market considerations for axial flux superconducting electric machine design

    Science.gov (United States)

    Ainslie, M. D.; George, A.; Shaw, R.; Dawson, L.; Winfield, A.; Steketee, M.; Stockley, S.

    2014-05-01

    In this paper, the authors investigate a number of design and market considerations for an axial flux superconducting electric machine design that uses high temperature superconductors. The axial flux machine design is assumed to utilise high temperature superconductors in both wire (stator winding) and bulk (rotor field) forms, to operate over a temperature range of 65-77 K, and to have a power output in the range from 10s of kW up to 1 MW (typical for axial flux machines), with approximately 2-3 T as the peak trapped field in the bulk superconductors. The authors firstly investigate the applicability of this type of machine as a generator in small- and medium-sized wind turbines, including the current and forecasted market and pricing for conventional turbines. Next, a study is also carried out on the machine's applicability as an in-wheel hub motor for electric vehicles. Some recommendations for future applications are made based on the outcome of these two studies. Finally, the cost of YBCO-based superconducting (2G HTS) wire is analysed with respect to competing wire technologies and compared with current conventional material costs and current wire costs for both 1G and 2G HTS are still too great to be economically feasible for such superconducting devices.

  11. A 3D Dynamic Lumped Parameter Thermal Network of Air-Cooled YASA Axial Flux Permanent Magnet Synchronous Machine

    Directory of Open Access Journals (Sweden)

    Abdalla Hussein Mohamed

    2018-03-01

    Full Text Available To find the temperature rise for high power density yokeless and segmented armature (YASA axial flux permanent magnet synchronous (AFPMSM machines quickly and accurately, a 3D lumped parameter thermal model is developed and validated experimentally and by finite element (FE simulations on a 4 kW YASA machine. Additionally, to get insight in the thermal transient response of the machine, the model accounts for the thermal capacitance of different machine components. The model considers the stator, bearing, and windage losses, as well as eddy current losses in the magnets on the rotors. The new contribution of this work is that the thermal model takes cooling via air channels between the magnets on the rotor discs into account. The model is parametrized with respect to the permanent magnet (PM angle ratio, the PM thickness ratio, the air gap length, and the rotor speed. The effect of the channels is incorporated via convection equations based on many computational fluid dynamics (CFD computations. The model accuracy is validated at different values of parameters by FE simulations in both transient and steady state. The model takes less than 1 s to solve for the temperature distribution.

  12. An electrostatic lower stator axial gap wobble motor: design and fabrication

    OpenAIRE

    Legtenberg, R.; Legtenberg, Rob; Berenschot, Johan W.; van Baar, J.J.J.; Lammerink, Theodorus S.J.; Elwenspoek, Michael Curt

    1995-01-01

    The fabrication, initial modelling and first results of an electrostatic lower stator axial gap wobble motor are presented. The four mask fabrication process is based on polysilicon surface micromachining techniques. Three to twelve stator pole wobble motor designs have been realized with rotor radii of 50 and 100 micrometer. A theoretical model predicts torque generations in the nNm range at high electrostatic fields. Motors have typically been operated between 10 and 20 Volts. Initial exper...

  13. Filter Influence on Rotor Losses in Coreless Axial Flux Permanent Magnet Machines

    Directory of Open Access Journals (Sweden)

    SANTIAGO, J.

    2013-02-01

    Full Text Available This paper investigates the eddy current losses induced in the rotor of coreless Axial-Flux machines. The calculation of eddy currents in the magnets requires the simulation of the inverter and the filter to obtain the harmonic content of the stator currents and FEM analysis of the magnets in the rotor. Due to the low inductance in coreless machines, the induced eddy current losses in the rotor remain lower than in traditional slotted machines. If only machine losses are considered, filters in DC/AC converters are not required in machines with wide airgaps as time harmonic losses in the rotor are very low.The harmonic content both from simulations and experimental results of a DC/AC converter are used to calculate the eddy currents in the rotor magnets. The properties of coreless machine topologies are investigated and some simplifications are proposed for time efficient 3D-FEM analysis. The time varying magnetic field can be considered constant over the magnets when the pole is divided in several magnets.The simplified FEM method to calculate eddy current losses is applicable to coreless machines with poles split into several magnets, although the conclusions are applicable to all coreless and slotless motors and generators.

  14. Multiobjective Design of Turbo Injection Mode for Axial Flux Motor in Plastic Injection Molding Machine by Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Jian-Long Kuo

    2015-01-01

    Full Text Available This paper proposes a turbo injection mode (TIM for an axial flux motor to apply onto injection molding machine. Since the injection molding machine requires different speed and force parameters setting when finishing a complete injection process. The interleaved winding structure in the motor provides two different injection levels to provide enough injection forces. Two wye-wye windings are designed to switch two control modes conveniently. Wye-wye configuration is used to switch two force levels for the motor. When only one set of wye-winding is energized, field weakening function is achieved. Both of the torque and speed increase under field weakening operation. To achieve two control objectives for torque and speed of the motor, fuzzy based multiple performance characteristics index (MPCI with particle swarm optimization (PSO is used to find out the multiobjective optimal design solution. Both of the torque and speed are expected to be maximal at the same time. Three control factors are selected as studied factors: winding diameter, winding type, and air-gap. Experimental results show that both of the torque and speed increase under the optimal condition. This will provide enough large torque and speed to perform the turbo injection mode in injection process for the injection molding machine.

  15. Performance analysis of a new radial-axial flux machine with SMC cores and ferrite magnets

    Science.gov (United States)

    Liu, Chengcheng; Wang, Youhua; Lei, Gang; Guo, Youguang; Zhu, Jianguo

    2017-05-01

    Soft magnetic composite (SMC) is a popular material in designing of new 3D flux electrical machines nowadays for it has the merits of isotropic magnetic characteristic, low eddy current loss and high design flexibility over the electric steel. The axial flux machine (AFM) with the extended stator tooth tip both in the radial and circumferential direction is a good example, which has been investigated in the last years. Based on the 3D flux AFM and radial flux machine, this paper proposes a new radial-axial flux machine (RAFM) with SMC cores and ferrite magnets, which has very high torque density though the low cost low magnetic energy ferrite magnet is utilized. Moreover, the cost of RAFM is quite low since the manufacturing cost can be reduced by using the SMC cores and the material cost will be decreased due to the adoption of the ferrite magnets. The 3D finite element method (FEM) is used to calculate the magnetic flux density distribution and electromagnetic parameters. For the core loss calculation, the rotational core loss computation method is used based on the experiment results from previous 3D magnetic tester.

  16. Research on an Axial Magnetic-Field-Modulated Brushless Double Rotor Machine

    Directory of Open Access Journals (Sweden)

    Bin Yu

    2013-09-01

    Full Text Available Double rotor machine, an electronic continuously variable transmission, has great potential in application of hybrid electric vehicles (HEVs, wind power and marine propulsion. In this paper, an axial magnetic-field-modulated brushless double rotor machine (MFM-BDRM, which can realize the speed decoupling between the shaft of the modulating ring rotor and that of the permanent magnet rotor is proposed. Without brushes and slip rings, the axial MFM-BDRM offers significant advantages such as excellent reliability and high efficiency. Since the number of pole pairs of the stator is not equal to that of the permanent magnet rotor, which differs from the traditional permanent magnet synchronous machine, the operating principle of the MFM-BDRM is deduced. The relations of corresponding speed and toque transmission are analytically discussed. The cogging toque characteristics, especially the order of the cogging torque are mathematically formulated. Matching principle of the number of pole pairs of the stator, that of the permanent magnet rotor and the number of ferromagnetic pole pieces is inferred since it affects MFM-BDRM’s performance greatly, especially in the respect of the cogging torque and electromagnetic torque ripple. The above analyses are assessed with the three-dimensional (3D finite-element method (FEM.

  17. Design of an Axial-Flux permanent magnet machine for an in-wheel direct drive application

    NARCIS (Netherlands)

    Bastiaens, K.; Jansen, J.W.; Jumayev, S.; Lomonova, E.A.

    2017-01-01

    This paper concerns the optimization and comparison of six different axial-flux permanent magnet (AFPM) machine topologies for an in-wheel direct drive application. The objective of the optimization is to reach maximum power density, which is of essence for an in-wheel motor. The machine topologies

  18. Axial electric wake field inside the induction gap exited by the intense electron beam

    International Nuclear Information System (INIS)

    Zhang Kaizhi; Zhang Huang; Long Jidong; Yang Guojun; He Xiaozhong; Wang Huacen

    2008-01-01

    While an intense electron beam passes through the accelerating gaps of a linear induction accelerator, a strong wake field will be excited. In this paper a relatively simple model is established based on the interaction between the transverse magnetic wake field and the electron beam, and the numerical calculation in succession generates a magnetic wake field distribution along the accelerator and along the beam pulse as well. The axial electric wake field is derived based on the relation between field components of a resonant mode. According to some principles in existence, the influence of this field on the high voltage properties of the induction gap is analyzed. The Dragon-I accelerator is taken as an example, and its maximum electric wake field is about 17 kV/cm, which means the effect of the wake field is noticeable. (authors)

  19. Effects of axial gap and nozzle distribution on aerodynamic forces of a supersonic partial-admission turbine

    Directory of Open Access Journals (Sweden)

    Jinpeng JIANG

    2017-12-01

    Full Text Available The turbine in an LH2/LOX rocket engine is designed as a two-stage supersonic partial-admission turbine. Three-dimensional steady and unsteady simulations were conducted to analyze turbine performance and aerodynamic forces on rotor blades. Different configurations were employed to investigate the effects of the axial gap and nozzle distribution on the predicted performance and aerodynamic forces. Rotor blades experience unsteady aerodynamic forces because of the partial admission. Aerodynamic forces show periodicity in the admission region, and are close to zero after leaving the admission region. The unsteady forces in frequency domain indicate that components exist in a wide frequency region, and the admission passing frequency is dominant. Those multiples of the rotational frequency which are multiples of the nozzle number in a full-admission turbine are notable components. Results show that the turbine efficiency decreases as the axial gap between nozzles and the 1st stage rotor (rotor 1 increases. Fluctuation of the circumferential aerodynamic force on rotor 1 blades decreases with the axial gap increasing. The turbine efficiency decreases as the circumferential spacing between nozzles increases. Fluctuations of the circumferential and axial aerodynamic forces increase as the circumferential spacing increases. As for the non-equidistant nozzle distribution, it produces similar turbine performance and amplitude-frequency characteristics of forces to those of the normal configuration, when the mean spacing is equal to that of the normal case. Keywords: Aerodynamic force, Axial gap, Computational fluid dynamics (CFD, Nozzle distribution, Partial admission, Turbine

  20. Engineering of multi-segmented light tunnel and flattop focus with designed axial lengths and gaps

    Science.gov (United States)

    Yu, Yanzhong; Huang, Han; Zhou, Mianmian; Zhan, Qiwen

    2018-01-01

    Based on the radiation pattern from a sectional-uniform line source antenna, a three-dimensional (3D) focus engineering technique for the creation of multi-segmented light tunnel and flattop focus with designed axial lengths and gaps is proposed. Under a 4Pi focusing system, the fields radiated from sectional-uniform magnetic and electromagnetic current line source antennas are employed to generate multi-segmented optical tube and flattop focus, respectively. Numerical results demonstrate that the produced light tube and flattop focus remain homogeneous along the optical axis; and their lengths of the nth segment and the nth gap between consecutive segments can be easily adjusted and only depend on the sizes of the nth section and the nth blanking between adjacent sectional antennas. The optical tube is a pure azimuthally polarized field but for the flattop focus the longitudinal polarization is dominant on the optical axis. To obtain the required pupil plane illumination for constructing the above focal field with prescribed characteristics, the inverse problem of the antenna radiation field is solved. These peculiar focusing fields might find potential applications in multi-particle acceleration, multi-particle trapping and manipulation.

  1. Investigation of a Co-Axial Dual-Mechanical Ports Flux-Switching Permanent Magnet Machine for Hybrid Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Wei Hua

    2015-12-01

    Full Text Available In this paper, a co-axial dual-mechanical ports flux-switching permanent magnet (CADMP-FSPM machine for hybrid electric vehicles (HEVs is proposed and investigated, which is comprised of two conventional co-axial FSPM machines, namely one high-speed inner rotor machine and one low-speed outer rotor machine and a non-magnetic ring sandwiched in between. Firstly, the topology and operation principle of the CADMP-FSPM machine are introduced; secondly, the control system of the proposed electronically-controlled continuously-variable transmission (E-CVT system is given; thirdly, the key design specifications of the CADMP-FSPM machine are determined based on a conventional dual-mechanical ports (DMP machine with a wound inner rotor. Fourthly, the performances of the CADMP-FSPM machine and the normal DMP machine under the same overall volume are compared, and the results indicate that the CADMP-FSPM machine has advantages over the conventional DMP machine in the elimination of brushes and slip rings, improved thermal dissipation conditions for the inner rotor, direct-driven operation, more flexible modes, lower cogging torque and torque ripple, lower total harmonic distortion (THD values of phase PM flux linkage and phase electro-motive force (EMF, higher torque output capability and is suitable for the E-CVT systems. Finally, the pros and cons of the CADMP-FSPM machine are highlighted. This paper lays a theoretical foundation for further research on CADMP-FSPM machines used for HEVs.

  2. Development of Correlations for Windage Power Losses Modeling in an Axial Flux Permanent Magnet Synchronous Machine with Geometrical Features of the Magnets

    Directory of Open Access Journals (Sweden)

    Alireza Rasekh

    2016-11-01

    Full Text Available In this paper, a set of correlations for the windage power losses in a 4 kW axial flux permanent magnet synchronous machine (AFPMSM is presented. In order to have an efficient machine, it is necessary to optimize the total electromagnetic and mechanical losses. Therefore, fast equations are needed to estimate the windage power losses of the machine. The geometry consists of an open rotor–stator with sixteen magnets at the periphery of the rotor with an annular opening in the entire disk. Air can flow in a channel being formed between the magnets and in a small gap region between the magnets and the stator surface. To construct the correlations, computational fluid dynamics (CFD simulations through the frozen rotor (FR method are performed at the practical ranges of the geometrical parameters, namely the gap size distance, the rotational speed of the rotor, the magnet thickness and the magnet angle. Thereafter, two categories of formulations are defined to make the windage losses dimensionless based on whether the losses are mainly due to the viscous forces or the pressure forces. At the end, the correlations can be achieved via curve fittings from the numerical data. The results reveal that the pressure forces are responsible for the windage losses for the side surfaces in the air-channel, whereas for the surfaces facing the stator surface in the gap, the viscous forces mainly contribute to the windage losses. Additionally, the results of the parametric study demonstrate that the overall windage losses in the machine escalate with an increase in either the rotational Reynolds number or the magnet thickness ratio. By contrast, the windage losses decrease once the magnet angle ratio enlarges. Moreover, it can be concluded that the proposed correlations are very useful tools in the design and optimizations of this type of electrical machine.

  3. FEM Analysis of a New Electromechanical Converter with Rolling Rotor and Axial Air-Gap

    Directory of Open Access Journals (Sweden)

    UNGUREANU, C.

    2015-11-01

    Full Text Available The paper presents the modeling of a new type of electromechanical converter with rolling rotor (ECRR in order to obtain an optimisation at functional level. The ECRR prototype comprises a stator composed of twelve magnetic poles and a disk-shaped rolling rotor made of ferromagnetic material, without windings. Each magnetic pole is made of an E-shaped magnetic system and a winding placed on its central column. The electromechanical converter with rolling rotor is analyzed through a magnetic field study with Flux2D software in magnetostatic application. The field study examines the influence of the rotor thickness, axial air-gap size and current density on the magnetic attraction force that changes the position of the disk-shaped rolling rotor. Also, it is analyzed the variation of the magnetic attraction force for different inclination angles of the rolling rotor. The main advantage of the ECRR is represented by a low rotational speed without using mechanical gearboxes. The ECRR prototype can be used in photovoltaic panels tracking systems.

  4. Study on Gap Flow Field Simulation in Small Hole Machining of Ultrasonic Assisted EDM

    Science.gov (United States)

    Liu, Yu; Chang, Hao; Zhang, Wenchao; Ma, Fujian; Sha, Zhihua; Zhang, Shengfang

    2017-12-01

    When machining a small hole with high aspect ratio in EDM, it is hard for the flushing liquid entering the bottom gap and the debris could hardly be removed, which results in the accumulation of debris and affects the machining efficiency and machining accuracy. The assisted ultrasonic vibration can improve the removal of debris in the gap. Based on dynamics simulation software Fluent, a 3D model of debris movement in the gap flow field of EDM small hole machining assisted with side flushing and ultrasonic vibration is established in this paper. When depth to ratio is 3, the laws of different amplitudes and frequencies on debris distribution and removal are quantitatively analysed. The research results show that periodic ultrasonic vibration can promote the movement of debris, which is beneficial to the removal of debris in the machining gap. Compared to traditional small hole machining in EDM, the debris in the machining gap is greatly reduced, which ensures the stability of machining process and improves the machining efficiency.

  5. FEAST 3.1: finite-element modeling of sheath deformation such as longitudinal ridging and collapse into axial gap

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.; Xu, Z.; Kim, Y-S.; Lai, L.; Cheng, G.; Xu, S. [Atomic Energy of Canada Limited, Mississauga, Ontario (Canada)

    2010-07-01

    During normal operation, the collapsible CANDU® fuel sheath deforms, especially, it may deform into longitudinal ridges or collapse instantaneously into the axial gaps between the end pellet and endcap or between two neighbouring pellets. These phenomena occur under certain conditions, such as the coolant pressure exceeding critical pressures for longitudinal ridging or axial collapse. Both longitudinal ridging and axial collapse phenomena result from plastic instability in the sheath under coolant pressure. Longitudinal ridging features one or multiple lobes or 'ridges' (outward from the sheath surface) formed along the sheath in the longitudinal direction. Axial collapse features a 'valley' around the sheath circumference. Both phenomena can lead to sheath overstrain, which in turn potentially leads to sheath failure. The LONGER code, which contains empirical correlations, has been used to predict the critical pressures for these two sheath deformation phenomena. To study fuel behaviour outside of the application ranges of the LONGER empirical correlations, a mechanistic model is needed. FEAST (Finite Element Analysis for Stresses) is an AECL computer code used to assess the structural integrity of the CANDU fuel element. The FEAST code has recently been developed (to Version 3.1) to model processes occurring during longitudinal ridge formation and instantaneous collapse into the axial gap. The new models include those for geometric non-linearity (large deformation, large material rotation), non-linear stress-strain curve for plastic deformation, Zr-4 sheath creep law, and variable Young’s Modulus etc. This paper describes the mechanistic model (FEAST 3.1) development for analyses of longitudinal ridging and instantaneous collapse into axial gap, and the comparison with the results from empirical correlations in LONGER. (author)

  6. FEAST 3.1: finite-element modeling of sheath deformation such as longitudinal ridging and collapse into axial gap

    International Nuclear Information System (INIS)

    Wang, X.; Xu, Z.; Kim, Y-S.; Lai, L.; Cheng, G.; Xu, S.

    2010-01-01

    During normal operation, the collapsible CANDU® fuel sheath deforms, especially, it may deform into longitudinal ridges or collapse instantaneously into the axial gaps between the end pellet and endcap or between two neighbouring pellets. These phenomena occur under certain conditions, such as the coolant pressure exceeding critical pressures for longitudinal ridging or axial collapse. Both longitudinal ridging and axial collapse phenomena result from plastic instability in the sheath under coolant pressure. Longitudinal ridging features one or multiple lobes or 'ridges' (outward from the sheath surface) formed along the sheath in the longitudinal direction. Axial collapse features a 'valley' around the sheath circumference. Both phenomena can lead to sheath overstrain, which in turn potentially leads to sheath failure. The LONGER code, which contains empirical correlations, has been used to predict the critical pressures for these two sheath deformation phenomena. To study fuel behaviour outside of the application ranges of the LONGER empirical correlations, a mechanistic model is needed. FEAST (Finite Element Analysis for Stresses) is an AECL computer code used to assess the structural integrity of the CANDU fuel element. The FEAST code has recently been developed (to Version 3.1) to model processes occurring during longitudinal ridge formation and instantaneous collapse into the axial gap. The new models include those for geometric non-linearity (large deformation, large material rotation), non-linear stress-strain curve for plastic deformation, Zr-4 sheath creep law, and variable Young’s Modulus etc. This paper describes the mechanistic model (FEAST 3.1) development for analyses of longitudinal ridging and instantaneous collapse into axial gap, and the comparison with the results from empirical correlations in LONGER. (author)

  7. Random non-proportional fatigue tests with planar tri-axial fatigue testing machine

    OpenAIRE

    Inoue, T.; Nagao, R.; Takeda, N.

    2016-01-01

    Complex stresses, which occur on the mechanical surfaces of transport machinery in service, bring a drastic degradation in fatigue life. However, it is hard to reproduce such complex stress states for evaluating the fatigue life with conventional multiaxial fatigue machines. We have developed a fatigue testing machine that enables reproduction of such complex stresses. The testing machine can reproduce arbitrary in-plane stress states by applying three independent loads to the test specimen u...

  8. Study on the Gap Flow Simulation in EDM Small Hole Machining with Ti Alloy

    Directory of Open Access Journals (Sweden)

    Shengfang Zhang

    2017-01-01

    Full Text Available In electrical discharge machining (EDM process, the debris removed from electrode material strongly affects the machining efficiency and accuracy, especially for the deep small hole machining process. In case of Ti alloy, the debris movement and removal process in gap flow between electrodes for small hole EDM process is studied in this paper. Based on the solid-liquid two-phase flow equation, the mathematical model on the gap flow field with flushing and self-adaptive disturbation is developed. In our 3D simulation process, the count of debris increases with number of EDM discharge cycles, and the disturbation generated by the movement of self-adaptive tool in the gap flow is considered. The methods of smoothing and remeshing are also applied in the modeling process to enable a movable tool. Under different depth, flushing velocity, and tool diameter, the distribution of velocity field, pressure field of gap flow, and debris movement are analyzed. The statistical study of debris distribution under different machining conditions is also carried out. Finally, a series of experiments are conducted on a self-made machine to verify the 3D simulation model. The experiment results show the burn mark at hole bottom and the tapered wall, which corresponds well with the simulating conclusion.

  9. Bridging the gap between human knowledge and machine learning

    Directory of Open Access Journals (Sweden)

    Juan Carlos ALVARADO-PÉREZ

    2015-12-01

    Full Text Available Nowadays, great amount of data is being created by several sources from academic, scientific, business and industrial activities. Such data intrinsically contains meaningful information allowing for developing techniques, and have scientific validity to explore the information thereof. In this connection, the aim of artificial intelligence (AI is getting new knowledge to make decisions properly. AI has taken an important place in scientific and technology development communities, and recently develops computer-based processing devices for modern machines. Under the premise, the premise that the feedback provided by human reasoning -which is holistic, flexible and parallel- may enhance the data analysis, the need for the integration of natural and artificial intelligence has emerged. Such an integration makes the process of knowledge discovery more effective, providing the ability to easily find hidden trends and patterns belonging to the database predictive model. As well, allowing for new observations and considerations from beforehand known data by using both data analysis methods and knowledge and skills from human reasoning. In this work, we review main basics and recent works on artificial and natural intelligence integration in order to introduce users and researchers on this emergent field. As well, key aspects to conceptually compare them are provided.

  10. Analysis and Design Considerations of a High-Power Density, Dual Air Gap, Axial-Field Brushless, Permanent Magnet Motor.

    Science.gov (United States)

    Cho, Chahee Peter

    1995-01-01

    Until recently, brush dc motors have been the dominant drive system because they provide easily controlled motor speed over a wide range, rapid acceleration and deceleration, convenient control of position, and lower product cost. Despite these capabilities, the brush dc motor configuration does not satisfy the design requirements for the U.S. Navy's underwater propulsion applications. Technical advances in rare-earth permanent magnet materials, in high-power semiconductor transistor technology, and in various rotor position-sensing devices have made using brushless permanent magnet motors a viable alternative. This research investigates brushless permanent magnet motor technology, studying the merits of dual-air gap, axial -field, brushless, permanent magnet motor configuration in terms of power density, efficiency, and noise/vibration levels. Because the design objectives for underwater motor applications include high-power density, high-performance, and low-noise/vibration, the traditional, simplified equivalent circuit analysis methods to assist in meeting these goals were inadequate. This study presents the development and verification of detailed finite element analysis (FEA) models and lumped parameter circuit models that can calculate back electromotive force waveforms, inductance, cogging torque, energized torque, and eddy current power losses. It is the first thorough quantification of dual air-gap, axial -field, brushless, permanent magnet motor parameters and performance characteristics. The new methodology introduced in this research not only facilitates the design process of an axial field, brushless, permanent magnet motor but reinforces the idea that the high-power density, high-efficiency, and low-noise/vibration motor is attainable.

  11. Bridging the Gap between Social Animal and Unsocial Machine: A Survey of Social Signal Processing

    NARCIS (Netherlands)

    Vinciarelli, Alessandro; Pantic, Maja; Heylen, Dirk K.J.; Pelachaud, Catherine; Poggi, Isabella; D’Ericco, Francesca; Schröder, Marc

    Social Signal Processing is the research domain aimed at bridging the social intelligence gap between humans and machines. This paper is the first survey of the domain that jointly considers its three major aspects, namely, modeling, analysis, and synthesis of social behavior. Modeling investigates

  12. Mechanics of Cutting and Boring. Part 7. Dynamics and Energetics of Axial Rotation Machines,

    Science.gov (United States)

    1981-12-01

    systematic analytical scheme that can be used to facilitate future work on the mechanics of cutting and boring machines. In the industrial sector, rock...Proceedings. Chapter 66, p. 1149-1158. Mellor, M. and I. Hawkes (1972) How to rate a hard-rock borer. World Construction, Sept, p. 21-23. (Also in Ingenieria

  13. Random non-proportional fatigue tests with planar tri-axial fatigue testing machine

    Directory of Open Access Journals (Sweden)

    T. Inoue

    2016-10-01

    Full Text Available Complex stresses, which occur on the mechanical surfaces of transport machinery in service, bring a drastic degradation in fatigue life. However, it is hard to reproduce such complex stress states for evaluating the fatigue life with conventional multiaxial fatigue machines. We have developed a fatigue testing machine that enables reproduction of such complex stresses. The testing machine can reproduce arbitrary in-plane stress states by applying three independent loads to the test specimen using actuators which apply loads in the 0, 45, and 90 degree directions. The reproduction was tested with complex stress data obtained from the actual operation of transport machinery. As a result, it was found that the reproduced stress corresponded to the measured stress with an error range of less than 10 %. Then, we made a comparison between measured fatigue lives under random non-proportional loading conditions and predicted fatigue lives. It was found that predicted fatigue lives with cr, stress on critical plane, were over a factor of 10 against measured fatigue lives. On the other hand, predicted fatigue lives with ma, stress in consideration of a non-proportional level evaluated by using amplitude and direction of principal stress, were within a factor of 3 against measured fatigue lives

  14. Optimization and Simulation of Machining Parameters in Radial-axial Ring Rolling Process

    Directory of Open Access Journals (Sweden)

    Shuiyuan Tang

    2011-05-01

    Full Text Available Ring rolling is a complicated process, in which rolling parameters influence directly the quality of ring. It is a process method with high productivity and few waste of material, widely used in transportation industry including automotive, shipbuilding, aerospace etc. During the rolling process of large-sized parts, crinkle and hollows often appear on surface, due to inconsistence of rolling motions with the deformation of ring part. Based on radial-axial ring rolling system configuration, motions and forces in rolling process are analyzed, and a dynamic model is formulated. Error of ring's end flatness and roundness are defined as the characteristic parameters of ring quality. The relationship between core roller feed speed, drive roller speed, the upper taper roller feed speed, and quality of ring part are analyzed. The stress and strain of the part are simulated in the Finite Element Method by DEFORM software. The simulation results provide a reference for the definition of ring rolling process parameters. It is able to make the deformation of the part be consistent with the process parameters, and improve product quality considerably.

  15. Investigation of the influence of air gap thickness and eccentricity on the noise of the rotating electrical machine

    Directory of Open Access Journals (Sweden)

    Donát M.

    2013-12-01

    Full Text Available This article deals with the numerical modelling of the dynamic response of the rotating electrical machine on the application of the magnetic forces. The special attention is paid to the modelling of the magnetic forces that act on the stator winding of the machine and the computational model of the modal properties of the stator winding. The created computational model was used to investigation of the influence of the nominal air gap thickness and the air gap eccentricity on the sound power radiated by outer surface of the stator of the machine. The obtained results show that the nominal air gap thickness has slightly greater influence on the sound power of the machine than eccentricity of the air gap.

  16. Phase II CRADA ORNL99-0568 Report : Developing Transmission-Less Inverter Drive Systems for Axial-Gap Permanent magnet Accessory and Traction Motors and Generators; FINAL

    International Nuclear Information System (INIS)

    McKeever, J.W.

    2001-01-01

    Researchers of the Oak Ridge National Laboratory's (ORNLs) Power Electronics and Electric Machine Research Center (PEEMRC) collaborated with Visual Computing Systems (VCS) to develop an electric axial-gap permanent magnet (PM) motor controlled by a self-sensing inverter for driving vehicle accessories such as power steering, air conditioning, and brakes. VCS designed an 8 kW motor based on their Segmented Electromagnetic Array (SEMA) technology. ORNL designed a 10 kW inverter to fit within the volume of a housing, which had been integrated with the motor. This modular design was pursued so that multiple modules could be used for higher power applications. ORNL built the first inverter under the cooperative research and development agreement (CRADA) ORNL 98-0514 and drove a refurbished Delta motor with no load during the Merit Review at ORNL on Monday, May 17, 1999. Inverter circuitry and instructions for assembling the inverters were sent to VCS. A report was prepared and delivered during the Future Car Congress in April 2000, at Arlington, Virginia. Collaboration continued under CRADA ORNL 99-0568 as VCS designed and built a SEMA motor with a dual coil platter to be the traction motor for an electric truck. VCS and ORNL assembled two 45 kW inverters. Each inverter drove one coil, which was designed to deliver 15 kW continuous power and 45 kW peak power for 90 s. The vehicle was road tested as part of the Future Truck Competition. A report was prepared and delivered during the PCIM in October 2000, at Boston, Massachusetts

  17. Gd-123 bulk field pole magnets cooled with condensed neon for axial-gap type synchronous motor

    International Nuclear Information System (INIS)

    Sano, T.; Kimura, Y.; Sugyo, D.; Yamaguchi, K.; Izumi, M.; Ida, T.; Sugimoto, H.; Miki, M.

    2008-01-01

    We have conducted to develop an axial-gap type synchronous propulsion motor with Gd-bulk HTS field pole magnets. It has been established on the fundamental technology upon the liquid nitrogen cooling. In the present study, we aimed an output improvement of the motor by the magnetic flux density enhancement of the bulk HTS, in a word, the trapped magnetic flux density on the HTS bulk. The output of the motor depends on the physics of the motor, the magnetic flux density, and the electric current density flowing through the armature. We have employed a condensed neon with a helium GM refrigerator. The bulk HTS placed on the rotor disk inside the motor frame was successfully cooled down with circulating condensed neon. The temperature at the bulk HTS surface reached 38 K. Upon magnetization, we developed controlled magnetic field density distribution coil (CMDC) composed of a couple of pulsed copper armature coil. In the magnetization procedure, with decreasing magnetization temperature, minute by minute, after Sander and Kamijyo that the step cooling magnetization method was used. In addition, the CMDC coil has enabled to control the applied flux distribution. Three parameters as the temperature, the applied magnetic field, and the effective applied flux density distribution were changed within eight times pulsed magnetizations in total. Up to 4th pulsed magnetization, we kept (1st step) high temperature, and subsequent pulsed magnetizations were done at low temperature. As a result, the highest maximum trapped magnetic flux density was reached 1.31 T, about 2.5 times compared to the value obtained upon cooling with liquid nitrogen. Consequently, the output of the motor has been enhanced to 25 kW from 10 kW taken in the previous operation

  18. Gap flows and pressure fields in sealing and bearing gaps of hydrostatic machines. Final report; Spaltstroemungen und Druckfelder in Dicht- und Lagerfugen hydrostatischer Maschinen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Kleist, A.

    1997-07-01

    The `hydrostatic machines` project was concerned with the examination of sealing and bearing gaps in hydraulic machines with the aim of creating a useful simulation tool for designing these gaps. In order to achieve this difficult target, extensive experimental investigations were carried out. A simulation program for the static calculation of sealing and bearing gaps was developed for the key gap bearing and the valve gap. The third main point of the experimental investigations was the examination of the piston/cylinder gap of a radial piston pump. The simulation was able to be verified from experimental results. (orig./AKF) [Deutsch] Das Projekt `Hydrostatische Maschinen` befasste sich mit der Untersuchung hydrostatischen Dicht- und Lagerfugen in hydraulischen Maschinen mit Ziel, fuer die Auslegung dieser Spalte ein handhabbares Simulationswerkzeug zu schaffen. Um dieses hochgesteckte Ziel zu erreichen, wurden umfangreiche experimentelle Untersuchungen durchgefuehrt. Fuer die Keilspaltlagerung und den Ventilsplat wurde ein Simulationsprogramm fuer die stationaere Berechnung von Dicht- und Lagerfugen entwickelt. Der dritte Schwerpunkt der experimentellen Untersuchungen war die Untersuchung des Kolben-Zylinder-Spaltes einer Radialkolbenpumpe. Die Simulation konnte anhand der experimentellen Ergebnisse verifiziert werden. (orig./AKF)

  19. The differential induction machine: Theory and performance

    Indian Academy of Sciences (India)

    feasibility of taking a turn. ... Thus the axial gap between the two rotors is also ... inductance than a normal machine due to the separating gap between the two rotors .... Crelerot O, Bernot F, Kauffmann J F 1993 Study of an electrical differential ...

  20. Triply coupled vibrational band gap in a periodic and nonsymmetrical axially loaded thin-walled Bernoulli-Euler beam including the warping effect

    International Nuclear Information System (INIS)

    Yu Dianlong; Fang Jianyu; Cai Li; Han Xiaoyun; Wen Jihong

    2009-01-01

    The propagation of triply coupled vibrations in a periodic, nonsymmetrical and axially loaded thin-walled Bernoulli-Euler beam composed of two kinds of materials is investigated with the transfer matrix method. The cross-section of the beam lacks symmetrical axes, and bending vibrations in the two perpendicular directions are coupled with torsional vibrations. Furthermore, the effect of warping stiffness is included. The band structures of the periodic beam, both including and excluding the warping effect, are obtained. The frequency response function of the finite periodic beam is simulated with the finite element method. These simulations show large vibration-based attenuation in the frequency range of the gap, as expected. By comparing the band structure of the beam with plane wave expansion method calculations that are available in the literature, one finds that including the warping effect leads to a more accurate simulation. The effects of warping stiffness and axial force on the band structure are also discussed.

  1. Effect of Machine Geometry on Higher Harmonics Content in Air-Gap Magnetic Field of Synchronous Reluctance Machine

    Czech Academy of Sciences Publication Activity Database

    Schreier, Luděk; Chomát, Miroslav; Doležel, Ivo

    2001-01-01

    Roč. 176, č. 1500 (2001), s. 259-266 ISSN 0072-4688 R&D Projects: GA ČR GA102/01/0181 Keywords : synchronous reluctance machine * torque pulsation Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  2. Real-time power angle determination of salient-pole synchronous machine based on air gap measurements

    Energy Technology Data Exchange (ETDEWEB)

    Despalatovic, Marin; Jadric, Martin; Terzic, Bozo [FESB University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture, R. Boskovica bb, 21000 Split (Croatia)

    2008-11-15

    This paper presents a new method for the real-time power angle determination of the salient-pole synchronous machines. This method is based on the terminal voltage and air gap measurements, which are the common features of the hydroturbine generator monitoring system. The raw signal of the air gap sensor is used to detect the rotor displacement with reference to the fundamental component of the terminal voltage. First, the algorithm developed for the real-time power angle determination is tested using the synthetic data obtained by the standard machine model simulation. Thereafter, the experimental investigation is carried out on the 26 MVA utility generator. The validity of the method is verified by comparing with another method, which is based on a tooth gear mounted on the rotor shaft. The proposed real-time algorithm has an adequate accuracy and needs a very short processing time. For applications that do not require real-time processing, such as the estimation of the synchronous machine parameters, the accuracy is additionally increased by applying an off-line data-processing algorithm. (author)

  3. Annual sums of carbon dioxide exchange over a heterogeneous urban landscape through machine learning based gap-filling

    Science.gov (United States)

    Menzer, Olaf; Meiring, Wendy; Kyriakidis, Phaedon C.; McFadden, Joseph P.

    2015-01-01

    A small, but growing, number of flux towers in urban environments measure surface-atmospheric exchanges of carbon dioxide by the eddy covariance method. As in all eddy covariance studies, obtaining annual sums of urban CO2 exchange requires imputation of data gaps due to low turbulence and non-stationary conditions, adverse weather, and instrument failures. Gap-filling approaches that are widely used for measurements from towers in natural vegetation are based on light and temperature response models. However, they do not account for key features of the urban environment including tower footprint heterogeneity and localized CO2 sources. Here, we present a novel gap-filling modeling framework that uses machine learning to select explanatory variables, such as continuous traffic counts and temporal variables, and then constrains models separately for spatially classified subsets of the data. We applied the modeling framework to a three year time series of measurements from a tall broadcast tower in a suburban neighborhood of Minneapolis-Saint Paul, Minnesota, USA. The gap-filling performance was similar to that reported for natural measurement sites, explaining 64% to 88% of the variability in the fluxes. Simulated carbon budgets were in good agreement with an ecophysiological bottom-up study at the same site. Total annual carbon dioxide flux sums for the tower site ranged from 1064 to 1382 g C m-2 yr-1, across different years and different gap-filling methods. Bias errors of annual sums resulting from gap-filling did not exceed 18 g C m-2 yr-1 and random uncertainties did not exceed ±44 g C m-2 yr-1 (or ±3.8% of the annual flux). Regardless of the gap-filling method used, the year-to-year differences in carbon exchange at this site were small. In contrast, the modeled annual sums of CO2 exchange differed by a factor of two depending on wind direction. This indicated that the modeled time series captured the spatial variability in both the biogenic and

  4. sizing of wind powered axial flux permanent magnet alternator using

    African Journals Online (AJOL)

    user

    2016-10-04

    Oct 4, 2016 ... Keywords: Wind-Power, Axial flux, Axial Flux Permanent Machines (AFPM), Axial Flux Permanent Magnet ... energy for power generation, a high constraint is the .... arrangements as Single-Rotor Single-Stator Structure.

  5. Analyzing distinctive rotor poles of the axial flux PM motors by using 3D-FEA in view of the magnetic equivalent circuit

    Directory of Open Access Journals (Sweden)

    Emrah Cetin

    2017-10-01

    Full Text Available Higher efficiency is always a desire for the electric machines researchers. One serious candidate is the axial flux permanent magnet motor to achieve that. These machines have advantages on power and torque density profile. This study aims to analyse the performances of the different rotor poles’ characteristics of the axial flux permanent magnet machines. The magnetic equivalent circuit designed and placed into the single gap axial flux permanent magnet machine to fathom the machine characteristic. The proposed rotors magnet poles are investigated in the view of the torque ripple reduction, back EMF waveforms and flux density distribution by using finite element analysis. Four different designs are compared. 3D analysis is used for FEA simulations. Torque ripple, back emf and magnetic flux distribution waveforms are obtained from the 3D FEA analysis. As a result, the proposed rotors are practicable and situated for higher performance.

  6. Axial myopathy

    DEFF Research Database (Denmark)

    Witting, Nanna; Andersen, Linda K; Vissing, John

    2016-01-01

    Classically, myopathies are categorized according to limb or cranial nerve muscle affection, but with the growing use of magnetic resonance imaging it has become evident that many well-known myopathies have significant involvement of the axial musculature. New disease entities with selective axial...

  7. HLA B27 antigen in Middle Eastern and Arab countries: systematic review of the strength of association with axial spondyloarthritis and methodological gaps.

    Science.gov (United States)

    Ziade, Nelly Raymond

    2017-06-29

    Axial spondyloarthritis (AxSpA) is a relatively frequent and debilitating disease, with a prevalence ranging from 0.1 to 2% in the Caucasian population. Current Assessment of Spondyloarthritis International Society (ASAS) classification criteria of AxSpA rely either on sacroiliitis on imaging plus one SpA feature or positive HLAB27 antigen plus two SpA features, in a patient with chronic low back pain and age at onset of less than 45 years. Therefore, HLA-B27 is a central feature in SpA classification and plays a pivotal role in referral strategies and early diagnosis. The primary objective of the study is to review the prevalence of HLA-B27 in normal and AxSpA populations in Middle Eastern and Arab Countries and to assess the strength of association between HLA-B27 antigen and AxSpA. The secondary objective is to identify the gaps in the methodology of the studies and suggest a framework for future research. Studies were included in the analysis if they reported prevalence of HLA-B27 in AxSpA and/or general population and if they covered geographical location in the Middle East or Arab countries in the Mediterranean basin. Odds ratios (OR) were calculated for each country, as a measure of the strength of association between HLA-B27 and AxSpA, compared to the normal population, using the two-by-two frequency table. Available data from the literature were analyzed according to the following quality indicators: sample size, method of HLA-B27 testing, presence of control group and external validity. Twenty-seven studies were analyzed. HLAB27 prevalence in the normal population ranged from 0.3% (Oman) to 6.8% (Turkey). HLA-B27 prevalence in AxSpA ranged from 26.2% (Lebanon) to 91% (Turkey). HLA-B27 prevalence in all SpA ranged from 13.87% (Lebanon) to 69.43% (Kuwait). Peripheral SpA was less associated with HLA-B27 than AxSpA, indicating the need of differentiating between the two entities when calculating prevalence. When available (8 studies), the OR ranged from 21

  8. Higher efficiency by direct driven spindles with sensorless controlled engine speed in multi-axial machine tools for the timber industry; Verbesserte Energieeffizienz durch direktangetriebene winkelgeberlose drehzahlgeregelte Spindeln bei Mehrachsbohrkoepfen fuer die holzverarbeitende Industrie

    Energy Technology Data Exchange (ETDEWEB)

    Teisch, Arthur; Obernolte, Urs; Borcherding, Holger [Hochschule Ostwestfalen Lippe, Lemgo (Germany)

    2009-07-01

    The multi-axial machine tools work mainly with spindles, who are powered by a central motor with a gearbox. These drives have a relative little power efficiency. Due to the progress of the magnetic material it was possible to change the central motor with gear box by small direct driven spindles. Cause of the very high efficiency of the permanentmagnet synchronous machine (PMSM), it is the best option for the new application. With the option of the sensorless control of the rotor speed the costs for an encoder are saved too. With the good efficiency of the PMSM the overall degree of efficiency could be raised by about 70%. Because of the reduced investment, service and energy costs the new systems are more economical to operate. (orig.)

  9. Experimental study of fuel bundle vibrations with rods subjected to mixed axial flow and cross-flow provided by a narrow gap (baffle jetting interaction)

    International Nuclear Information System (INIS)

    Boulanger, P.; Jacques, Y.; Fardeau, P.; Barbier, D.; Rigaudeau, J.

    1997-01-01

    The Hydraulic Core Laboratory (LHC) performs experimental studies of PWR fuel assembly mechanical behaviour submitted to representative flows in PWR core. Cross-flows prove particularly troublesome by generating on rods, in special cases, vibratory levels high enough to induce early grid to rod fretting. The fluid-structure interaction under mixed axial and cross-flow is also a major topic for analysis. The authors present a test loop devoted to the mixed axial-cross-flow fluid-structure interaction on representative half-scale mockup which is able to simulate, under ambient conditions, any complex flow (direction and flow rates) representative of PWR core flows. Despite its reduced size, the mockup retains the overall structure of a PWR fuel assembly. Rods displacement/velocity and velocity flow field are measured by laser techniques

  10. Gap flow in axial turbines. Effects on the flow patterns in the final turbine stage and inside the diffusor. Final report

    International Nuclear Information System (INIS)

    Krueckels, J.

    1996-01-01

    A 3D Navier-Stokes method was modified for discretisation of the gap between the tip of the rotor blade and the casing wall by an additional grid block. Flow calculations were carried out using a zoned approach in which the Navier-Stokes equations are solved only in the gap flow region inside the rotor while the Eulerian equations are solved in the other regions, thus reducing the calculation time. The results are compared with experimental data. The interdependence between turbine and diffusor is taken into account so that the pressure distribution at the rotor outlet will be modelled correctly. The distribution of static pressure at the diffusor outlet must be available as an input variable in this method [de

  11. Design, dimensioning and control of a synchronous motor/generator with homopolar excitation and coils inside the air gap for electromechanical energy accumulator; Conception, dimensionnement et commande d'un moteur/generateur synchrone a excitation homopolaire et a bobinages dans l'entrefer pour accumulateur electromecanique d'energie

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, N.

    2001-12-15

    A new axial field machine with armature and field windings fixed in the air-gap is studied. A double face printed winding is presented and a new tool, using a surface permeance model is developed. A simplified current control is proposed. Finally, considering the association synchronous machine-inverter the loss minimization problem is investigated, including both geometry and command parameters. (author)

  12. Axial tomography

    International Nuclear Information System (INIS)

    Brueckner, K.A.; Lewis, J.H.

    1979-01-01

    The invention relates to axial tomography, sometimes referred to as cross-sectional x-ray. The apparatus described may utilize the conventional x-ray or ultrasonic source and detector and scanning mechanism for producing the plurality of sets of radiation detector output signals. It has the means for storing the detector output signals in analog form with the signals of one set overlying the signals of another set so that signals resulting from radiation through a zone of the object being examined are summed at a corresponding zone in the storage device, typically an electronic storage tube. The summed signals are read from the storage device with a radially inversely proportional reader producing a second signal for storage, again typically in an electronic storage tube. These signals stored in the second storage device are read with Laplacian relation, with the resultant sigal being a video signal that may be connected to a TV monitor for display of the sectional image. In alternative embodiments, optical film systems and electrostatic systems are utilized. (JTA)

  13. Finite Element Analysis in the Estimation of Air-Gap Torque and Surface Temperature of Induction Machine

    Science.gov (United States)

    Mr., J. Ravi Kumar; Banakara, Basavaraja, Dr.

    2017-08-01

    This paper presents electromagnetic and thermal behavior of Induction Motor (IM) through the modeling and analysis by applying multiphysics coupled Finite Element Analysis (FEA). Therefore prediction of the magnetic flux, electromagnetic torque, stator and rotor losses and temperature distribution inside an operating electric motor are the most important issues during its design. Prediction and estimation of these parameters allows design engineers to decide capability of the machine for the proposed load, temperature rating and its application for which it is being designed ensuring normal motor operation at rated conditions. In this work, multiphysics coupled electromagnetic - thermal modeling and analysis of induction motor at rated and high frequency has carried out applying Arkkio’s torque method. COMSOL Multiphysics software is used for modeling and finite element analysis of IM. Transient electromagnetic torque, magnetic field distribution, speed-torque characteristics of IM were plotted and studied at different frequencies. This proposed work helps in the design and prediction of accurate performance of induction motor specific to various industrial drive applications. Results obtained are also validated with experimental analysis. The main purpose of this model is to use it as an integral part of the design aiming to system optimization of Variable Speed Drive (VSD) and its components using coupled simulations.

  14. Transonic airfoil and axial flow rotary machine

    Science.gov (United States)

    Nagai, Naonori; Iwatani, Junji

    2015-09-01

    Sectional profiles close to a tip 124 and a part between a midportion 125 and a hub 123 are shifted to the upstream of an operating fluid flow in a sweep direction. Accordingly, an S shape is formed in which the tip 124 and the part between the midportion 125 and the hub 123 protrude. As a result, it is possible reduce various losses due to shook, waves, thereby forming a transonic airfoil having an excellent aerodynamic characteristic.

  15. Machine protection systems

    CERN Document Server

    Macpherson, A L

    2010-01-01

    A summary of the Machine Protection System of the LHC is given, with particular attention given to the outstanding issues to be addressed, rather than the successes of the machine protection system from the 2009 run. In particular, the issues of Safe Machine Parameter system, collimation and beam cleaning, the beam dump system and abort gap cleaning, injection and dump protection, and the overall machine protection program for the upcoming run are summarised.

  16. An overview of rotating machine systems with high-temperature bulk superconductors

    Science.gov (United States)

    Zhou, Difan; Izumi, Mitsuru; Miki, Motohiro; Felder, Brice; Ida, Tetsuya; Kitano, Masahiro

    2012-10-01

    The paper contains a review of recent advancements in rotating machines with bulk high-temperature superconductors (HTS). The high critical current density of bulk HTS enables us to design rotating machines with a compact configuration in a practical scheme. The development of an axial-gap-type trapped flux synchronous rotating machine together with the systematic research works at the Tokyo University of Marine Science and Technology since 2001 are briefly introduced. Developments in bulk HTS rotating machines in other research groups are also summarized. The key issues of bulk HTS machines, including material progress of bulk HTS, in situ magnetization, and cooling together with AC loss at low-temperature operation are discussed.

  17. Superconducting-electromagnetic hybrid bearing using YBCO bulk blocks for passive axial levitation

    Science.gov (United States)

    Nicolsky, R.; de Andrade, R., Jr.; Ripper, A.; David, D. F. B.; Santisteban, J. A.; Stephan, R. M.; Gawalek, W.; Habisreuther, T.; Strasser, T.

    2000-06-01

    A superconducting/electromagnetic hybrid bearing has been designed using active radial electromagnetic positioning and a superconducting passive axial levitator. This bearing has been tested for an induction machine with a vertical shaft. The prototype was conceived as a four-pole, two-phase induction machine using specially designed stator windings for delivering torque and radial positioning simultaneously. The radial bearing uses four eddy-current sensors, displaced 90° from each other, for measuring the shaft position and a PID control system for feeding back the currents. The stator windings have been adapted from the ones of a standard induction motor. The superconducting axial bearing has been assembled with commercial NdFeB permanent magnets and a set of seven top-seeded-melt-textured YBCO large-grain cylindrical blocks. The bearing set-up was previously simulated by a finite element method for different permanent magnet-superconductor block configurations. The stiffness of the superconducting axial bearing has been investigated by measuring by a dynamic method the vertical and transversal elastic constants for different field cooling processes. The resulting elastic constants show a linear dependence on the air gap, i.e. the clearance between the permanent magnet assembly and the set of superconducting large-grain blocks, which is dependent on cooling distance.

  18. System and method for smoothing a salient rotor in electrical machines

    Science.gov (United States)

    Raminosoa, Tsarafidy; Alexander, James Pellegrino; El-Refaie, Ayman Mohamed Fawzi; Torrey, David A.

    2016-12-13

    An electrical machine exhibiting reduced friction and windage losses is disclosed. The electrical machine includes a stator and a rotor assembly configured to rotate relative to the stator, wherein the rotor assembly comprises a rotor core including a plurality of salient rotor poles that are spaced apart from one another around an inner hub such that an interpolar gap is formed between each adjacent pair of salient rotor poles, with an opening being defined by the rotor core in each interpolar gap. Electrically non-conductive and non-magnetic inserts are positioned in the gaps formed between the salient rotor poles, with each of the inserts including a mating feature formed an axially inner edge thereof that is configured to mate with a respective opening being defined by the rotor core, so as to secure the insert to the rotor core against centrifugal force experienced during rotation of the rotor assembly.

  19. Modeling and analysis of mover gaps in tubular moving-magnet linear oscillating motors

    Directory of Open Access Journals (Sweden)

    Xuesong LUO

    2018-05-01

    Full Text Available A tubular moving-magnet linear oscillating motor (TMMLOM has merits of high efficiency and excellent dynamic capability. To enhance the thrust performance, quasi-Halbach permanent magnet (PM arrays are arranged on its mover in the application of a linear electro-hydrostatic actuator in more electric aircraft. The arrays are assembled by several individual segments, which lead to gaps between them inevitably. To investigate the effects of the gaps on the radial magnetic flux density and the machine thrust in this paper, an analytical model is built considering both axial and radial gaps. The model is validated by finite element simulations and experimental results. Distributions of the magnetic flux are described in condition of different sizes of radial and axial gaps. Besides, the output force is also discussed in normal and end windings. Finally, the model has demonstrated that both kinds of gaps have a negative effect on the thrust, and the linear motor is more sensitive to radial ones. Keywords: Air-gap flux density, Linear motor, Mover gaps, Quasi-Halbach array, Thrust output, Tubular moving-magnet linear oscillating motor (TMMLOM

  20. BWR AXIAL PROFILE

    International Nuclear Information System (INIS)

    Huffer, J.

    2004-01-01

    The purpose of this calculation is to develop axial profiles for estimating the axial variation in burnup of a boiling water reactor (BWR) assembly spent nuclear fuel (SNF) given the average burnup of an assembly. A discharged fuel assembly typically exhibits higher burnup in the center and lower burnup at the ends of the assembly. Criticality safety analyses taking credit for SNF burnup must account for axially varying burnup relative to calculations based on uniformly distributed assembly average burnup due to the under-burned tips. Thus, accounting for axially varying burnup in criticality analyses is also referred to as accounting for the ''end effect'' reactivity. The magnitude of the reactivity change due to ''end effect'' is dependent on the initial assembly enrichment, the assembly average burnup, and the particular axial profile characterizing the burnup distribution. The set of bounding axial profiles should incorporate multiple BWR core designs and provide statistical confidence (95 percent confidence that 95 percent of the population is bound by the profile) that end nodes are conservatively represented. The profiles should also conserve the overall burnup of the fuel assembly. More background on BWR axial profiles is provided in Attachment I

  1. Computerised Axial Tomography (CAT)

    Science.gov (United States)

    1990-06-01

    Ministry of’ Defence, Defence Research Information Centre, UK. Computerised Axial Tomography ( CAT ) Report Secufty C"uMiauion tide Onadtiicadon (U. R, Cor S...DRIC T 8485 COMPUTERISED AXIAL TOMOGRAPHY ( CAT ) F.P. GENTILE, F. SABETTA, V. TRO1* ISS R 78/4.Rome, 1.5 Mlarch 1978 (from Italian) B Distribution(f...dello Radiazioni ISSN 0390--6477 F.P. GENTILE, F. SABETTA. V. TROI Computerised Axial Tomography ( CAT ) March 15, 1978). This paper is a review of

  2. Axial flow heat exchanger devices and methods for heat transfer using axial flow devices

    Science.gov (United States)

    Koplow, Jeffrey P.

    2016-02-16

    Systems and methods described herein are directed to rotary heat exchangers configured to transfer heat to a heat transfer medium flowing in substantially axial direction within the heat exchangers. Exemplary heat exchangers include a heat conducting structure which is configured to be in thermal contact with a thermal load or a thermal sink, and a heat transfer structure rotatably coupled to the heat conducting structure to form a gap region between the heat conducting structure and the heat transfer structure, the heat transfer structure being configured to rotate during operation of the device. In example devices heat may be transferred across the gap region from a heated axial flow of the heat transfer medium to a cool stationary heat conducting structure, or from a heated stationary conducting structure to a cool axial flow of the heat transfer medium.

  3. Signatures for axial chromodynamics

    International Nuclear Information System (INIS)

    Pati, J.C.

    1978-07-01

    Within the context of basic left-right symmetry and the hypothesis of unification of weak, electromagnetic and strong forces at a mass level approximately equal to 10 4 -10 6 GeV, relatively light ''mass'' axial gluons, confined or liberated, must be postulated. The authors remark that the existence of such ''light'' axial gluons supplementing the familiar vector octet preserves the successes of QCD, both for deep inelastic processes and charmonium physics. Through the characteristic spin-spin force, generated by their exchange, they may even help resolve some of the discrepancies between vector QCD predictions and charmonium physics. The main remark of this note is that if colour is liberated, not only vector but also axial-vector gluons are produced in high-energy e - e + experiments, e.g. at PETRA and PEP, with fairly large cross-section. Distinctive decay modes of such liberated axial gluons are noted

  4. GAP Analysis Program (GAP)

    Data.gov (United States)

    Kansas Data Access and Support Center — The Kansas GAP Analysis Land Cover database depicts 43 land cover classes for the state of Kansas. The database was generated using a two-stage hybrid classification...

  5. Development of an Axial Flux MEMS BLDC Micromotor with Increased Efficiency and Power Density

    Directory of Open Access Journals (Sweden)

    Xiaofeng Ding

    2015-06-01

    Full Text Available This paper presents a rigorous design and optimization of an axial flux microelectromechanical systems (MEMS brushless dc (BLDC micromotor with dual rotor improving both efficiency and power density with an external diameter of only around 10 mm. The stator is made of two layers of windings by MEMS technology. The rotor is developed by film permanent magnets assembled over the rotor yoke. The characteristics of the MEMS micromotor are analyzed and modeled through a 3-D magnetic equivalent circuit (MEC taking the leakage flux and fringing effect into account. Such a model yields a relatively accurate prediction of the flux in the air gap, back electromotive force (EMF and electromagnetic torque, whilst being computationally efficient. Based on 3-D MEC model the multi-objective firefly algorithm (MOFA is developed for the optimal design of this special machine. Both 3-D finite element (FE simulation and experiments are employed to validate the MEC model and MOFA optimization design.

  6. On renormalization of axial anomaly

    International Nuclear Information System (INIS)

    Efremov, A.V.; Teryaev, O.V.

    1989-01-01

    It is shown that multiplicative renormalization of the axial singlet current results in renormalization of the axial anomaly in all orders of perturbation theory. It is a necessary condition for the Adler - Bardeen theorem being valid. 10 refs.; 2 figs

  7. Axial tomographic scanner

    International Nuclear Information System (INIS)

    1976-01-01

    An axial tomographic system is described comprising axial tomographic means for collecting sets of data corresponding to the transmission or absorption of a number of beams of penetrating radiation through a planar slice of an object. It includes means to locate an object to be analyzed, a source and detector for directing one or more beams of penetrating radiation through the object from the source to the detector, and means to rotate (and optionally translate) the source as well as means to process the collected sets of data. Data collection, data processing, and data display can each be conducted independently of each other. An additional advantage of the system described is that the raw data (i.e., the originally collected data) are not destroyed by the data processing but instead are retained intact for further reference or use, if needed

  8. Fabrication and testing of diamond-machined gratings in ZnSe, GaP, and bismuth germanate for the near infrared and visible

    Energy Technology Data Exchange (ETDEWEB)

    Kuzmenko, P J; Little, S L; Ikeda, Y; Kobayashi, N

    2008-06-22

    High quality immersion gratings for infrared applications have been demonstrated in silicon and germanium. To extend this technology to shorter wavelengths other materials must be investigated. We selected three materials, zinc selenide, gallium phosphide and bismuth germanate (Bi{sub 4}Ge{sub 3}O{sub 12}), based on high refractive index, good visible transmission and commercial availability in useful sizes. Crystal samples were diamond turned on an ultra-precision lathe to identify preferred cutting directions. Using this information we diamond-flycut test gratings over a range of feed rates to determine the optimal cutting conditions. For both ZnSe and GaP good surface quality was achieved at feed rates up to 1.0 cm/minute using a special compound angle diamond tool with negative rake angles on both cutting surfaces. The surface roughness of the groove facets was about 4 nm. A Zygo interferometer measured grating wavefront errors in reflection. For the ZnSe the RMS error was < {lambda}/20 at 633nm. More extensive testing was performed with a HeNe laser source and a cooled CCD camera. These measurements demonstrated high relative diffraction efficiency (> 80%), low random groove error (2.0 nm rms), and Rowland ghost intensities at < 0.1%. Preliminary tests on bismuth germanate show high tool wear.

  9. Critical Axial Load

    Directory of Open Access Journals (Sweden)

    Walt Wells

    2008-01-01

    Full Text Available Our objective in this paper is to solve a second order differential equation for a long, simply supported column member subjected to a lateral axial load using Heun's numerical method. We will use the solution to find the critical load at which the column member will fail due to buckling. We will calculate this load using Euler's derived analytical approach for an exact solution, as well as Euler's Numerical Method. We will then compare the three calculated values to see how much they deviate from one another. During the critical load calculation, it will be necessary to calculate the moment of inertia for the column member.

  10. Reducing Torque Ripples of the Axial Flux PM Motors by Magnet Stepping and Shifting

    Directory of Open Access Journals (Sweden)

    E. Cetin

    2018-02-01

    Full Text Available Higher efficiency on electric machines is the research goal of many studies. An example is the axial flux permanent magnet machines. These machines have some advantages like their watt/kg efficiency and torque density. This study aims to develop the performance characteristics of the axial flux permanent magnet machines. A new rotor magnet poles design in axial flux machines is suggested to mitigate the torque ripples. The method of stepping and shifting of the magnets is used. Two different designs are compared to verify the proposed approach. 3D finite element analysis is used for simulations. Torque ripple and back electromotive force waveforms are obtained from computer analysis. As a conclusion, the suggested method is found to be useable and mitigates the torque ripples. In addition to that, back EMF waveforms are turned to sinusoidal by the suggested design.

  11. Machine Shop Grinding Machines.

    Science.gov (United States)

    Dunn, James

    This curriculum manual is one in a series of machine shop curriculum manuals intended for use in full-time secondary and postsecondary classes, as well as part-time adult classes. The curriculum can also be adapted to open-entry, open-exit programs. Its purpose is to equip students with basic knowledge and skills that will enable them to enter the…

  12. Coil Optimization for HTS Machines

    DEFF Research Database (Denmark)

    Mijatovic, Nenad; Jensen, Bogi Bech; Abrahamsen, Asger Bech

    An optimization approach of HTS coils in HTS synchronous machines (SM) is presented. The optimization is aimed at high power SM suitable for direct driven wind turbines applications. The optimization process was applied to a general radial flux machine with a peak air gap flux density of ~3T...... is suitable for which coil segment is presented. Thus, the performed study gives valuable input for the coil design of HTS machines ensuring optimal usage of HTS tapes....

  13. Computational analysis of a multistage axial compressor

    Science.gov (United States)

    Mamidoju, Chaithanya

    Turbomachines are used extensively in Aerospace, Power Generation, and Oil & Gas Industries. Efficiency of these machines is often an important factor and has led to the continuous effort to improve the design to achieve better efficiency. The axial flow compressor is a major component in a gas turbine with the turbine's overall performance depending strongly on compressor performance. Traditional analysis of axial compressors involves throughflow calculations, isolated blade passage analysis, Quasi-3D blade-to-blade analysis, single-stage (rotor-stator) analysis, and multi-stage analysis involving larger design cycles. In the current study, the detailed flow through a 15 stage axial compressor is analyzed using a 3-D Navier Stokes CFD solver in a parallel computing environment. Methodology is described for steady state (frozen rotor stator) analysis of one blade passage per component. Various effects such as mesh type and density, boundary conditions, tip clearance and numerical issues such as turbulence model choice, advection model choice, and parallel processing performance are analyzed. A high sensitivity of the predictions to the above was found. Physical explanation to the flow features observed in the computational study are given. The total pressure rise verses mass flow rate was computed.

  14. Compound induction electric rotating machine

    Energy Technology Data Exchange (ETDEWEB)

    Decesare, D

    1987-07-28

    The present invention generally relates to dynamo-electric machines cabable of operating in a generator mode or in a motor mode and more specifically, to increased efficiency compound interaction AC and/or DC dynamo-electric machines. This patent describes such a machine having a distributed armature winding in a cylindrical rotor wound to form axial and substantially radial winding portions and including permanent and/or electromagnets to couple magnetic flux into the peripheral or circumferential surface of the rotor, and to provide interaction between a magnetic field formed beyond the rotor axial surfaces and the rotor to thereby enhance the total induction of flux into the rotor for improved, more efficient operation. 28 figs.,

  15. Axial skeletal CT densitometry

    International Nuclear Information System (INIS)

    Lampmann, L.E.H.

    1982-01-01

    Since the discovery of the Roentgen ray a precise and accurate assessment of bone mineral content has been a challenge to many investigators. A number of methods have been developed but no one satisfied. Considering its technical possibilities computed tomography is very promising in determination of bone mineral content (BMC). The new modality enables BMC estimations in the axial skeletal trabecular bone. CT densitometry can be performed on a normal commercially available third generation whole body CT scanner. No dedicated device in a special clinical set-up is necessary. In this study 106 patients, most of them clinically suspected of osteoporosis, were examined. The new method CT densitometry has been evaluated. The results have been correlated to alternative BMC determination methods. (Auth.)

  16. Advanced SLARette delivery machine

    International Nuclear Information System (INIS)

    Bodner, R.R.

    1995-01-01

    SLARette 1 equipment, comprising of a SLARette Delivery Machine, SLAR Tools, SLAR power supplies and SLAR Inspection Systems was designed, developed and manufactured to service fuel channels of CANDU 6 stations during the regular yearly station outages. The Mark 2 SLARette Delivery Machine uses a Push Tube system to provide the axial and rotary movements of the SLAR Tool. The Push Tubes are operated remotely but must be attached and removed manually. Since this operation is performed at the Reactor face, there is radiation dose involved for the workers. An Advanced SLARette Delivery Machine which incorporates a computer controlled telescoping Ram in the place of the Push Tubes has been recently designed and manufactured. Utilization of the Advanced SLARette Delivery Machine significantly reduces the amount of radiation dose picked up by the workers because the need to have workers at the face of the Reactor during the SLARette operation is greatly reduced. This paper describes the design, development and manufacturing process utilized to produce the Advanced SLARette Delivery Machine and the experience gained during the Gentilly-2 NGS Spring outage. (author)

  17. Evaluation of axial fission gas transport in power ramping experiments

    International Nuclear Information System (INIS)

    Kinoshita, Motoyasu

    1986-01-01

    The LINUS code calculates advective and diffusional transport of fission gas towards an upper plenum through the pellet-cladding gap. The basic equations were modified for analyzing a multi-component gas mixture in the gap and also for dealing with opening and/or closing of the gap, which induces additional axial gas flow. Analysis of the Petten ramp experiment shows that helium pressurization is effective in suppressing an ascending rate of fission gas concentration. After the maximum concentration is achieved through power ramping, the gas concentration could be described by a steady state analytical solution which does not depend on the filling gas pressure. (author)

  18. Operation and machine studies

    International Nuclear Information System (INIS)

    1992-01-01

    This annual report describes the GANIL (Grand accelerateur national d'ions lourds, Caen, France) operation and the machine studies realized in 1992. Metallic ions have been accelerated during 36 pc of the time; some were produced for the first time at GANIL: 125 Te, 52 Cr with ECR3, 181 Ta with ECR4. The various machine studies are: comparison of lifetimes of carbon sheets, charge exchange of very heavy ions in carbon foils and in the residual gas of the Ganil cyclotrons, commissioning of the new high intensity axial injection system for Ganil, tantalum acceleration with the new injector, a cyclotron as a mass spectrometer; other studies concerned: implementing the new control system, gettering flux measurement, energy deposited by neutrons and gamma rays in the cryogenic system of SISSI; latest developments on multicharged ECR ion sources, and an on-line isotopic separator test bench at Ganil

  19. Dissipative Axial Inflation

    CERN Document Server

    Notari, Alessio

    2016-12-22

    We analyze in detail the background cosmological evolution of a scalar field coupled to a massless abelian gauge field through an axial term $\\frac{\\phi}{f_\\gamma} F \\tilde{F}$, such as in the case of an axion. Gauge fields in this case are known to experience tachyonic growth and therefore can backreact on the background as an effective dissipation into radiation energy density $\\rho_R$, which which can lead to inflation without the need of a flat potential. We analyze the system, for momenta $k$ smaller than the cutoff $f_\\gamma$, including numerically the backreaction. We consider the evolution from a given static initial condition and explicitly show that, if $f_\\gamma$ is smaller than the field excursion $\\phi_0$ by about a factor of at least ${\\cal O} (20)$, there is a friction effect which turns on before that the field can fall down and which can then lead to a very long stage of inflation with a generic potential. In addition we find superimposed oscillations, which would get imprinted on any kind of...

  20. Methods and apparatus for controlling rotary machines

    Science.gov (United States)

    Bagepalli, Bharat Sampathkumaran [Niskayuna, NY; Jansen, Patrick Lee [Scotia, NY; Barnes, Gary R [Delanson, NY; Fric, Thomas Frank [Greer, SC; Lyons, James Patrick Francis [Niskayuna, NY; Pierce, Kirk Gee [Simpsonville, SC; Holley, William Edwin [Greer, SC; Barbu, Corneliu [Guilderland, NY

    2009-09-01

    A control system for a rotary machine is provided. The rotary machine has at least one rotating member and at least one substantially stationary member positioned such that a clearance gap is defined between a portion of the rotating member and a portion of the substantially stationary member. The control system includes at least one clearance gap dimension measurement apparatus and at least one clearance gap adjustment assembly. The adjustment assembly is coupled in electronic data communication with the measurement apparatus. The control system is configured to process a clearance gap dimension signal and modulate the clearance gap dimension.

  1. Sustainable machining

    CERN Document Server

    2017-01-01

    This book provides an overview on current sustainable machining. Its chapters cover the concept in economic, social and environmental dimensions. It provides the reader with proper ways to handle several pollutants produced during the machining process. The book is useful on both undergraduate and postgraduate levels and it is of interest to all those working with manufacturing and machining technology.

  2. Aerodynamic Modelling and Optimization of Axial Fans

    DEFF Research Database (Denmark)

    Sørensen, Dan Nørtoft

    A numerically efficient mathematical model for the aerodynamics oflow speed axial fans of the arbitrary vortex flow type has been developed.The model is based on a blade-element principle, whereby therotor is divided into a number of annular streamtubes.For each of these streamtubes relations......-Raphson method, andsolutions converged to machine accuracy are found at small computing costs.The model has been validated against published measurementson various fan configurations,comprising two rotor-only fan stages, a counter-rotatingfan unit and a stator-rotor-stator stage.Comparisons of local...... and integrated propertiesshow that the computed results agree well with the measurements.Integrating a rotor-only version of the aerodynamic modelwith an algorithm for numerical designoptimization, enables the finding of an optimum fan rotor.The angular velocity of the rotor, the hub radius and the spanwise...

  3. Characterization of Multiflux Axial Compressors

    International Nuclear Information System (INIS)

    Brasnarof, Daniel; Kyung Kyu-Hyung; Rivarola, Martin; Gonzalez Jose; Florido, Pablo; Orellano, Pablo; Bergallo, Juan

    2003-01-01

    In the present work the results of analytical models of performance are compared with experimental data acquired in the multi flux axial compressor test facility, built in The Pilcaniyeu Technological Complex for the SIGMA project.We describe the experimental circuit and the data of the dispersion inside the axial compressor obtained using a tracer gas through one of the annular inlets.The attained results can be used to validate the design code for the multi flux axial compressors and SIGMA industrial plant

  4. Study of axial magnetic effect

    Energy Technology Data Exchange (ETDEWEB)

    Braguta, Victor [IHEP, Protvino, Moscow region, 142284 Russia ITEP, B. Cheremushkinskaya street 25, Moscow, 117218 (Russian Federation); School of Biomedicine, Far Eastern Federal University, Ajax 10 Building 25, Russian island, Vladivostok, 690922 (Russian Federation); Chernodub, M. N. [CNRS, Laboratoire de Mathématiques et Physique Théorique, Université François-Rabelais Tours, Fédération Denis Poisson, Parc de Grandmont, 37200 Tours, France Department of Physics and Astronomy, University of Gent, Krijgslaan 281, S9, B-9000 Gent (Belgium); School of Biomedicine, Far Eastern Federal University, Ajax 10 Building 25, Russian island, Vladivostok, 690922 (Russian Federation); Goy, V. A. [School of Natural Sciences, Far Eastern Federal University, Sukhanova street 8, Vladivostok, 690950 (Russian Federation); Landsteiner, K. [Instituto de Física Teórica UAM/CSIC, C/ Nicolás Cabrera 13-15, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Molochkov, A. V. [School of Biomedicine, Far Eastern Federal University, Ajax 10 Building 25, Russian island, Vladivostok, 690922 (Russian Federation); Ulybyshev, M. [ITEP, B. Cheremushkinskaya street 25, Moscow, 117218 Russia Institute for Theoretical Problems of Microphysics, Moscow State University, Moscow, 119899 (Russian Federation)

    2016-01-22

    The Axial Magnetic Effect manifests itself as an equilibrium energy flow of massless fermions induced by the axial (chiral) magnetic field. Here we study the Axial Magnetic Effect in the quenched SU(2) lattice gauge theory with massless overlap fermions at finite temperature. We numerically observe that in the low-temperature hadron phase the effect is absent due to the quark confinement. In the high-temperature deconfinement phase the energy flow is an increasing function of the temperature which reaches the predicted asymptotic T{sup 2} behavior at high temperatures. We find, however, that energy flow is about one order of magnitude lower compared to a theoretical prediction.

  5. Double U-Core Switched Reluctance Machine

    DEFF Research Database (Denmark)

    2016-01-01

    The present invention relates to an electrical machine stator comprising a plurality of stator segments (131,132,133), each segment comprises a first U-core and a second U-core wound with a winding, where the winding being arranged with at least one coil turn, each coil turn comprises a first axial......(s), wherein the first U-core and the second U-core are located adjacent to each other, whereby the winding spans the first and second U-cores. The invention also relates to a SRM machine with a stator mentioned above and a rotor....

  6. Dissipative axial inflation

    Energy Technology Data Exchange (ETDEWEB)

    Notari, Alessio [Departament de Física Fondamental i Institut de Ciències del Cosmos, Universitat de Barcelona, Martí i Franquès 1, Barcelona, 08028 Spain (Spain); Tywoniuk, Konrad, E-mail: notari@ffn.ub.es, E-mail: konrad.tywoniuk@cern.ch [Theoretical Physics Department, CERN, Geneva (Switzerland)

    2016-12-01

    We analyze in detail the background cosmological evolution of a scalar field coupled to a massless abelian gauge field through an axial term φ/ f {sub γ} F ∼ F , such as in the case of an axion. Gauge fields in this case are known to experience tachyonic growth and therefore can backreact on the background as an effective dissipation into radiation energy density ρ{sub R}, which can lead to inflation without the need of a flat potential. We analyze the system, for momenta k smaller than the cutoff f {sub γ}, including the backreaction numerically. We consider the evolution from a given static initial condition and explicitly show that, if f {sub γ} is smaller than the field excursion φ{sub 0} by about a factor of at least O (20), there is a friction effect which turns on before the field can fall down and which can then lead to a very long stage of inflation with a generic potential. In addition we find superimposed oscillations, which would get imprinted on any kind of perturbations, scalars and tensors. Such oscillations have a period of 4–5 efolds and an amplitude which is typically less than a few percent and decreases linearly with f {sub γ}. We also stress that the curvature perturbation on uniform density slices should be sensitive to slow-roll parameters related to ρ{sub R} rather than φ-dot {sup 2}/2 and we discuss the existence of friction terms acting on the perturbations, although we postpone a calculation of the power spectrum and of non-gaussianity to future work and we simply define and compute suitable slow roll parameters. Finally we stress that this scenario may be realized in the axion case, if the coupling 1/ f {sub γ} to U(1) (photons) is much larger than the coupling 1/ f {sub G} to non-abelian gauge fields (gluons), since the latter sets the range of the potential and therefore the maximal allowed φ{sub 0∼} f {sub G}.

  7. Gap Resolution

    Energy Technology Data Exchange (ETDEWEB)

    2017-04-25

    Gap Resolution is a software package that was developed to improve Newbler genome assemblies by automating the closure of sequence gaps caused by repetitive regions in the DNA. This is done by performing the follow steps:1) Identify and distribute the data for each gap in sub-projects. 2) Assemble the data associated with each sub-project using a secondary assembler, such as Newbler or PGA. 3) Determine if any gaps are closed after reassembly, and either design fakes (consensus of closed gap) for those that closed or lab experiments for those that require additional data. The software requires as input a genome assembly produce by the Newbler assembler provided by Roche and 454 data containing paired-end reads.

  8. Simple machines

    CERN Document Server

    Graybill, George

    2007-01-01

    Just how simple are simple machines? With our ready-to-use resource, they are simple to teach and easy to learn! Chocked full of information and activities, we begin with a look at force, motion and work, and examples of simple machines in daily life are given. With this background, we move on to different kinds of simple machines including: Levers, Inclined Planes, Wedges, Screws, Pulleys, and Wheels and Axles. An exploration of some compound machines follows, such as the can opener. Our resource is a real time-saver as all the reading passages, student activities are provided. Presented in s

  9. Gap Junctions

    Science.gov (United States)

    Nielsen, Morten Schak; Axelsen, Lene Nygaard; Sorgen, Paul L.; Verma, Vandana; Delmar, Mario; Holstein-Rathlou, Niels-Henrik

    2013-01-01

    Gap junctions are essential to the function of multicellular animals, which require a high degree of coordination between cells. In vertebrates, gap junctions comprise connexins and currently 21 connexins are known in humans. The functions of gap junctions are highly diverse and include exchange of metabolites and electrical signals between cells, as well as functions, which are apparently unrelated to intercellular communication. Given the diversity of gap junction physiology, regulation of gap junction activity is complex. The structure of the various connexins is known to some extent; and structural rearrangements and intramolecular interactions are important for regulation of channel function. Intercellular coupling is further regulated by the number and activity of channels present in gap junctional plaques. The number of connexins in cell-cell channels is regulated by controlling transcription, translation, trafficking, and degradation; and all of these processes are under strict control. Once in the membrane, channel activity is determined by the conductive properties of the connexin involved, which can be regulated by voltage and chemical gating, as well as a large number of posttranslational modifications. The aim of the present article is to review our current knowledge on the structure, regulation, function, and pharmacology of gap junctions. This will be supported by examples of how different connexins and their regulation act in concert to achieve appropriate physiological control, and how disturbances of connexin function can lead to disease. © 2012 American Physiological Society. Compr Physiol 2:1981-2035, 2012. PMID:23723031

  10. Single Stator Dual PM Rotor Synchronous Machine with two-frequency single-inverter control, for the propulsion of hybrid electric vehicles

    Directory of Open Access Journals (Sweden)

    Topor Marcel

    2017-01-01

    Full Text Available This paper introduces a novel brushless, single winding and single stator, dual PM rotor axial-air-gap machine capable to deliver independently torque at the two rotors by adequate dual vector control. The proposed topologies, the circuit model, controlled dynamics simulation and preliminary 3D FEM torque production on a case study constitute the core of the paper. The proposed dual mechanical port system should be instrumental in parallel (with planetary gears or series hybrid electric vehicles (HEV aiming at a more compact and efficient electric propulsion system solution.

  11. Face machines

    Energy Technology Data Exchange (ETDEWEB)

    Hindle, D.

    1999-06-01

    The article surveys latest equipment available from the world`s manufacturers of a range of machines for tunnelling. These are grouped under headings: excavators; impact hammers; road headers; and shields and tunnel boring machines. Products of thirty manufacturers are referred to. Addresses and fax numbers of companies are supplied. 5 tabs., 13 photos.

  12. Electric machine

    Science.gov (United States)

    El-Refaie, Ayman Mohamed Fawzi [Niskayuna, NY; Reddy, Patel Bhageerath [Madison, WI

    2012-07-17

    An interior permanent magnet electric machine is disclosed. The interior permanent magnet electric machine comprises a rotor comprising a plurality of radially placed magnets each having a proximal end and a distal end, wherein each magnet comprises a plurality of magnetic segments and at least one magnetic segment towards the distal end comprises a high resistivity magnetic material.

  13. Machine Learning.

    Science.gov (United States)

    Kirrane, Diane E.

    1990-01-01

    As scientists seek to develop machines that can "learn," that is, solve problems by imitating the human brain, a gold mine of information on the processes of human learning is being discovered, expert systems are being improved, and human-machine interactions are being enhanced. (SK)

  14. Nonplanar machines

    International Nuclear Information System (INIS)

    Ritson, D.

    1989-05-01

    This talk examines methods available to minimize, but never entirely eliminate, degradation of machine performance caused by terrain following. Breaking of planar machine symmetry for engineering convenience and/or monetary savings must be balanced against small performance degradation, and can only be decided on a case-by-case basis. 5 refs

  15. Machine intelligence and signal processing

    CERN Document Server

    Vatsa, Mayank; Majumdar, Angshul; Kumar, Ajay

    2016-01-01

    This book comprises chapters on key problems in machine learning and signal processing arenas. The contents of the book are a result of a 2014 Workshop on Machine Intelligence and Signal Processing held at the Indraprastha Institute of Information Technology. Traditionally, signal processing and machine learning were considered to be separate areas of research. However in recent times the two communities are getting closer. In a very abstract fashion, signal processing is the study of operator design. The contributions of signal processing had been to device operators for restoration, compression, etc. Applied Mathematicians were more interested in operator analysis. Nowadays signal processing research is gravitating towards operator learning – instead of designing operators based on heuristics (for example wavelets), the trend is to learn these operators (for example dictionary learning). And thus, the gap between signal processing and machine learning is fast converging. The 2014 Workshop on Machine Intel...

  16. Tooth-coil permanent magnet synchronous machine design for special applications

    Energy Technology Data Exchange (ETDEWEB)

    Ponomarev, P.

    2013-11-01

    This doctoral thesis presents a study on the design of tooth-coil permanent magnet synchronous machines. The electromagnetic properties of concentrated non-overlapping winding permanent magnet synchronous machines, or simply tooth-coil permanent magnet synchronous machines (TC-PMSMs), are studied in details. It is shown that current linkage harmonics play the deterministic role in the behavior of this type of machines. Important contributions are presented as regards of calculation of parameters of TC-PMSMs,particularly the estimation of inductances. The current linkage harmonics essentially define the air-gap harmonic leakage inductance, rotor losses and localized temporal inductance variation. It is proven by FEM analysis that inductance variation caused by the local temporal harmonic saturation results in considerable torque ripple, and can influence on sensorless control capabilities. Example case studies an integrated application of TC-IPMSMs in hybrid off-highway working vehicles. A methodology for increasing the efficiency of working vehicles is introduced. It comprises several approaches - hybridization, working operations optimization, component optimization and integration. As a result of component optimization and integration, a novel integrated electro-hydraulic energy converter (IEHEC) for off-highway working vehicles is designed. The IEHEC can considerably increase the operational efficiency of a hybrid working vehicle. The energy converter consists of an axial-piston hydraulic machine and an integrated TCIPMSM being built on the same shaft. The compact assembly of the electrical and hydraulic machines enhances the ability to find applications for such a device in the mobile environment of working vehicles.Usage of hydraulic fluid, typically used in working actuators, enables direct-immersion oil cooling of designed electrical machine, and further increases the torque- and power- densities of the whole device. (orig.)

  17. Mythic gaps

    Directory of Open Access Journals (Sweden)

    William Hansen

    2014-11-01

    Full Text Available Different kinds of omissions sometimes occur, or are perceived to occur, in traditional narratives and in tradition-inspired literature. A familiar instance is when a narrator realizes that he or she does not fully remember the story that he or she has begun to tell, and so leaves out part of it, which for listeners may possibly result in an unintelligible narrative. But many instances of narrative gap are not so obvious. From straightforward, objective gaps one can distinguish less-obvious subjective gaps: in many cases narrators do not leave out anything crucial or truly relevant from their exposition, and yet readers perceive gaps and take steps to fill them. The present paper considers four examples of subjective gaps drawn from ancient Greek literature (the Pandora myth, ancient Roman literature (the Pygmalion legend, ancient Hebrew literature (the Joseph legend, and early Christian literature (the Jesus legend. I consider the quite varied ways in which interpreters expand the inherited texts of these stories, such as by devising names, manufacturing motives, creating backstories, and in general filling in biographical ellipses. Finally, I suggest an explanation for the phenomenon of subjective gaps, arguing that, despite their variety, they have a single cause.

  18. Functional Correspondence between Evaluators and Abstract Machines

    DEFF Research Database (Denmark)

    Ager, Mads Stig; Biernacki, Dariusz; Danvy, Olivier

    2003-01-01

    We bridge the gap between functional evaluators and abstract machines for the λ-calculus, using closure conversion, transformation into continuation-passing style, and defunctionalization.We illustrate this approach by deriving Krivine's abstract machine from an ordinary call-by-name evaluator...... and by deriving an ordinary call-by-value evaluator from Felleisen et al.'s CEK machine. The first derivation is strikingly simpler than what can be found in the literature. The second one is new. Together, they show that Krivine's abstract machine and the CEK machine correspond to the call-by-name and call...

  19. The Machine within the Machine

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    Although Virtual Machines are widespread across CERN, you probably won't have heard of them unless you work for an experiment. Virtual machines - known as VMs - allow you to create a separate machine within your own, allowing you to run Linux on your Mac, or Windows on your Linux - whatever combination you need.   Using a CERN Virtual Machine, a Linux analysis software runs on a Macbook. When it comes to LHC data, one of the primary issues collaborations face is the diversity of computing environments among collaborators spread across the world. What if an institute cannot run the analysis software because they use different operating systems? "That's where the CernVM project comes in," says Gerardo Ganis, PH-SFT staff member and leader of the CernVM project. "We were able to respond to experimentalists' concerns by providing a virtual machine package that could be used to run experiment software. This way, no matter what hardware they have ...

  20. Machine translation

    Energy Technology Data Exchange (ETDEWEB)

    Nagao, M

    1982-04-01

    Each language has its own structure. In translating one language into another one, language attributes and grammatical interpretation must be defined in an unambiguous form. In order to parse a sentence, it is necessary to recognize its structure. A so-called context-free grammar can help in this respect for machine translation and machine-aided translation. Problems to be solved in studying machine translation are taken up in the paper, which discusses subjects for semantics and for syntactic analysis and translation software. 14 references.

  1. Aerodynamic modelling and optimization of axial fans

    Energy Technology Data Exchange (ETDEWEB)

    Noertoft Soerensen, Dan

    1998-01-01

    A numerically efficient mathematical model for the aerodynamics of low speed axial fans of the arbitrary vortex flow type has been developed. The model is based on a blade-element principle, whereby the rotor is divided into a number of annular stream tubes. For each of these stream tubes relations for velocity, pressure and radial position are derived from the conservation laws for mass, tangential momentum and energy. The equations are solved using the Newton-Raphson methods, and solutions converged to machine accuracy are found at small computing costs. The model has been validated against published measurements on various fan configurations, comprising two rotor-only fan stages, a counter-rotating fan unit and a stator-rotor stator stage. Comparisons of local and integrated properties show that the computed results agree well with the measurements. Optimizations have been performed to maximize the mean value of fan efficiency in a design interval of flow rates, thus designing a fan which operates well over a range of different flow conditions. The optimization scheme was used to investigate the dependence of maximum efficiency on 1: the number of blades, 2: the width of the design interval and 3: the hub radius. The degree of freedom in the choice of design variable and constraints, combined with the design interval concept, provides a valuable design-tool for axial fans. To further investigate the use of design optimization, a model for the vortex shedding noise from the trailing edge of the blades has been incorporated into the optimization scheme. The noise emission from the blades was minimized in a flow rate design point. Optimizations were performed to investigate the dependence of the noise on 1: the number of blades, 2: a constraint imposed on efficiency and 3: the hub radius. The investigations showed, that a significant reduction of noise could be achieved, at the expense of a small reduction in fan efficiency. (EG) 66 refs.

  2. A note on axial symmetries

    International Nuclear Information System (INIS)

    Beetle, Christopher; Wilder, Shawn

    2015-01-01

    This note describes how to characterize and normalize an axial Killing field on a general Riemannian geometry or four-dimensional Lorentzian geometry. No global assumptions are necessary, such as that the orbits of the Killing field all have period 2π. Rather, any Killing field that vanishes at at least one point necessarily has the expected global properties. (note)

  3. Axial structure of the nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Veronique Bernard; Latifa Elouadrhiri; Ulf-G Meissner

    2002-01-01

    We review the current status of experimental and theoretical understanding of the axial nucleon structure at low and moderate energies. Topics considered include (quasi)elastic (anti)neutrino-nucleon scattering, charged pion electroproduction off nucleons and ordinary as well as radiative muon capture on the proton.

  4. Machine Learning

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    Machine learning, which builds on ideas in computer science, statistics, and optimization, focuses on developing algorithms to identify patterns and regularities in data, and using these learned patterns to make predictions on new observations. Boosted by its industrial and commercial applications, the field of machine learning is quickly evolving and expanding. Recent advances have seen great success in the realms of computer vision, natural language processing, and broadly in data science. Many of these techniques have already been applied in particle physics, for instance for particle identification, detector monitoring, and the optimization of computer resources. Modern machine learning approaches, such as deep learning, are only just beginning to be applied to the analysis of High Energy Physics data to approach more and more complex problems. These classes will review the framework behind machine learning and discuss recent developments in the field.

  5. Machine Translation

    Indian Academy of Sciences (India)

    Research Mt System Example: The 'Janus' Translating Phone Project. The Janus ... based on laptops, and simultaneous translation of two speakers in a dialogue. For more ..... The current focus in MT research is on using machine learning.

  6. Efficient Propulsion Structure with an Axial Flux Rotary Converter for HEV Drive Unit

    Directory of Open Access Journals (Sweden)

    Ales Havel

    2011-01-01

    Full Text Available This paper describes an efficient axial flux arrangement of the four quadrant rotary converter for hybrid electric vehicles. The design of the axial flux wound stator and both axial flux squirrel cage rotors is based on the arrangement of radial air gap induction motor and permanent magnet synchronous motor. The method of constant magnetic circuit volume is utilized for dimensions conversion, which results into basic dimensions of stator and rotor discs in axial flux conception. This allows the creation of real 3D models in the CAD application. Finally, the finite element simulations of electromagnetic induction in the axial flux stator pack are presented in the concluding part of this paper.

  7. Performance of a Folded-Strip Toroidally Wound Induction Machine

    DEFF Research Database (Denmark)

    Jensen, Bogi Bech; Jack, Alan G.; Atkinson, Glynn J.

    2011-01-01

    This paper presents the measured experimental results from a four-pole toroidally wound induction machine, where the stator is constructed as a pre-wound foldable strip. It shows that if the machine is axially restricted in length, the toroidally wound induction machine can have substantially...... shorter stator end-windings than conventionally wound induction machines, and hence that a toroidally wound induction machine can have lower losses and a higher efficiency. The paper also presents the employed construction method, which emphasizes manufacturability, and highlights the advantages...

  8. Electrical machines with Matlab

    CERN Document Server

    Gonen, Turan

    2011-01-01

    Basic ConceptsDistribution SystemImpact of Dispersed Storage and GenerationBrief Overview of Basic Electrical MachinesReal and Reactive Powers in Single-Phase AC CircuitsThree-Phase CircuitsThree-Phase SystemsUnbalanced Three-Phase LoadsMeasurement of Average Power in Three-Phase CircuitsPower Factor CorrectionMagnetic CircuitsMagnetic Field of Current-Carrying ConductorsAmpère's Magnetic Circuital LawMagnetic CircuitsMagnetic Circuit with Air GapBrief Review of FerromagnetismMagnetic Core LossesHow to Determine Flux for a Given MMFPermanent MagnetsTransformersTransformer ConstructionBrief Rev

  9. [Comparison of machinability of two types of dental machinable ceramic].

    Science.gov (United States)

    Fu, Qiang; Zhao, Yunfeng; Li, Yong; Fan, Xinping; Li, Yan; Lin, Xuefeng

    2002-11-01

    In terms of the problems of now available dental machinable ceramics, a new type of calcium-mica glass-ceramic, PMC-I ceramic, was developed, and its machinability was compared with that of Vita MKII quantitatively. Moreover, the relationship between the strength and the machinability of PMC-I ceramic was studied. Samples of PMC-I ceramic were divided into four groups according to their nucleation procedures. 600-seconds drilling tests were conducted with high-speed steel tools (Phi = 2.3 mm) to measure the drilling depths of Vita MKII ceramic and PMC-I ceramic, while constant drilling speed of 600 rpm and constant axial load of 39.2 N were used. And the 3-point bending strength of the four groups of PMC-I ceramic were recorded. Drilling depth of Vita MKII was 0.71 mm, while the depths of the four groups of PMC-I ceramic were 0.88 mm, 1.40 mm, 0.40 mm and 0.90 mm, respectively. Group B of PMC-I ceramic showed the largest depth of 1.40 mm and was statistically different from other groups and Vita MKII. And the strength of the four groups of PMC-I ceramic were 137.7, 210.2, 118.0 and 106.0 MPa, respectively. The machinability of the new developed dental machinable ceramic of PMC-I could meet the need of the clinic.

  10. Three-Dimensional Temperature Field Calculation and Analysis of an Axial-Radial Flux-Type Permanent Magnet Synchronous Motor

    Directory of Open Access Journals (Sweden)

    Dong Li

    2018-05-01

    Full Text Available This article concentrates on the steady-state thermal characteristics of the Axial-Radial Flux-Type Permanent Magnet Synchronous Motor (ARFTPMSM. Firstly, the three-dimensional mathematical models for electromagnetic calculation and analyses are established, and the machine loss, including the stator loss, armature winding loss, rotor loss, and axial structure loss is calculated by using time-step Finite Element Method (FEM. Then, the loss distribution is assigned as the heat source for the thermal calculation. Secondly, the mathematical model for thermal calculation is also established. The assumptions and the boundary conditions are proposed to simplify the calculation and to improve convergence. Thirdly, the three-dimensional electromagnetic and thermal calculations of the machine, of which the armature winding and axial field winding are developed by using copper wires, are solved, from which the temperature distributions of the machine components are obtained. The experiments are carried out on the prototype with copper wires to validate the accuracy of the established models. Then, the temperature distributions of machine components under different Axial Magnetic Motive Force (AMMF are investigated. Since the machine is finally developing by using HTS wires, the temperature distributions of machine developed by utilizing High Temperature Superconducting (HTS wires, are also studied. The temperature distribution differences of the machine developed by using copper wires and HTS wires are drawn. All of these above will provide a helpful reference for the thermal calculation of the ARFTPMSM, as well as the design of the HTS coils and the cryogenic cooling system.

  11. Axial magnetic field produced by axially and radially magnetized permanent rings

    International Nuclear Information System (INIS)

    Peng, Q.L.; McMurry, S.M.; Coey, J.M.D.

    2004-01-01

    Axial magnetic fields produced by axially and radially magnetized permanent magnet rings were studied. First, the axial magnetic field produced by a current loop is introduced, from which the axial field generated by an infinitely thin solenoid and by an infinitely thin current disk can be derived. Then the axial fields produced by axially and by radially magnetized permanent magnet rings can be obtained. An analytic formula for the axial fields produced by two axially magnetized rings is given. A permanent magnet with a high axial gradient field is fabricated, the measured results agree with the theoretical calculation very well. As an example, the axial periodic field produced by an arrangement of alternating axially and radially magnetized rings has been discussed

  12. View of the Axial Field Spectrometer

    CERN Multimedia

    1980-01-01

    The Axial Field Spectrometer, with the vertical uranium/scintillator calorimeter and the central drift chamber retracted for service. One coil of the Open Axial Field Magnet is just visible to the right.

  13. Axial-Centrifugal Compressor Program

    Science.gov (United States)

    1975-10-01

    Assembly . .. . .... ..... 33 5 Tie Bolt...... .. .. .. .. . *.. .. .. .. .. .. ... 34 6 Axial Compressor Rotor Assembly Runouts . . .. . 34 7 CCV Blow...1.796 Impeller Slip Factor ’Ce2/U 2 ) .91 Impeller Wheel Speed ft/sec 1992.2 Impellet ’.ip Radius in. 3.780 Blade Tip Metal Angle- deg 0 Numbec of Blades...test item to the next Phase V component test. The test vehicle final balance levels and rotor runouts were normal at teardown, and no rubsI were

  14. Knowledge Gaps

    DEFF Research Database (Denmark)

    Lyles, Marjorie; Pedersen, Torben; Petersen, Bent

    2003-01-01

    The study explores what factors influence the reduction of managers' perceivedknowledge gaps in the context of the environments of foreign markets. Potentialdeterminants are derived from traditional internationalization theory as well asorganizational learning theory, including the concept...... of absorptive capacity. Building onthese literature streams a conceptual model is developed and tested on a set of primarydata of Danish firms and their foreign market operations. The empirical study suggeststhat the factors that pertain to the absorptive capacity concept - capabilities ofrecognizing......, assimilating, and utilizing knowledge - are crucial determinants ofknowledge gap elimination. In contrast, the two factors deemed essential in traditionalinternationalization process theory - elapsed time of operations and experientiallearning - are found to have no or limited effect.Key words...

  15. Axial length and keratometry readings in Nigeria- a guide to biometr

    African Journals Online (AJOL)

    Dr Adio

    though not ideal may be useful where biometric machines are either not available or faulty. Surgeries are increasingly being done in the rural areas and in camp settings and a working figure for the axial length and/or keratometry values in the locality where the procedure is taking place are useful. The average A-scan ...

  16. Machine Protection

    International Nuclear Information System (INIS)

    Zerlauth, Markus; Schmidt, Rüdiger; Wenninger, Jörg

    2012-01-01

    The present architecture of the machine protection system is being recalled and the performance of the associated systems during the 2011 run will be briefly summarized. An analysis of the causes of beam dumps as well as an assessment of the dependability of the machine protection systems (MPS) itself is being presented. Emphasis will be given to events that risked exposing parts of the machine to damage. Further improvements and mitigations of potential holes in the protection systems will be evaluated along with their impact on the 2012 run. The role of rMPP during the various operational phases (commissioning, intensity ramp up, MDs...) will be discussed along with a proposal for the intensity ramp up for the start of beam operation in 2012

  17. Machine Learning

    Energy Technology Data Exchange (ETDEWEB)

    Chikkagoudar, Satish; Chatterjee, Samrat; Thomas, Dennis G.; Carroll, Thomas E.; Muller, George

    2017-04-21

    The absence of a robust and unified theory of cyber dynamics presents challenges and opportunities for using machine learning based data-driven approaches to further the understanding of the behavior of such complex systems. Analysts can also use machine learning approaches to gain operational insights. In order to be operationally beneficial, cybersecurity machine learning based models need to have the ability to: (1) represent a real-world system, (2) infer system properties, and (3) learn and adapt based on expert knowledge and observations. Probabilistic models and Probabilistic graphical models provide these necessary properties and are further explored in this chapter. Bayesian Networks and Hidden Markov Models are introduced as an example of a widely used data driven classification/modeling strategy.

  18. Machine Protection

    CERN Document Server

    Zerlauth, Markus; Wenninger, Jörg

    2012-01-01

    The present architecture of the machine protection system is being recalled and the performance of the associated systems during the 2011 run will be briefly summarized. An analysis of the causes of beam dumps as well as an assessment of the dependability of the machine protection systems (MPS) itself is being presented. Emphasis will be given to events that risked exposing parts of the machine to damage. Further improvements and mitigations of potential holes in the protection systems will be evaluated along with their impact on the 2012 run. The role of rMPP during the various operational phases (commissioning, intensity ramp up, MDs...) will be discussed along with a proposal for the intensity ramp up for the start of beam operation in 2012.

  19. Machine Protection

    Energy Technology Data Exchange (ETDEWEB)

    Zerlauth, Markus; Schmidt, Rüdiger; Wenninger, Jörg [European Organization for Nuclear Research, Geneva (Switzerland)

    2012-07-01

    The present architecture of the machine protection system is being recalled and the performance of the associated systems during the 2011 run will be briefly summarized. An analysis of the causes of beam dumps as well as an assessment of the dependability of the machine protection systems (MPS) itself is being presented. Emphasis will be given to events that risked exposing parts of the machine to damage. Further improvements and mitigations of potential holes in the protection systems will be evaluated along with their impact on the 2012 run. The role of rMPP during the various operational phases (commissioning, intensity ramp up, MDs...) will be discussed along with a proposal for the intensity ramp up for the start of beam operation in 2012.

  20. Teletherapy machine

    International Nuclear Information System (INIS)

    Panyam, Vinatha S.; Rakshit, Sougata; Kulkarni, M.S.; Pradeepkumar, K.S.

    2017-01-01

    Radiation Standards Section (RSS), RSSD, BARC is the national metrology institute for ionizing radiation. RSS develops and maintains radiation standards for X-ray, beta, gamma and neutron radiations. In radiation dosimetry, traceability, accuracy and consistency of radiation measurements is very important especially in radiotherapy where the success of patient treatment is dependent on the accuracy of the dose delivered to the tumour. Cobalt teletherapy machines have been used in the treatment of cancer since the early 1950s and India had its first cobalt teletherapy machine installed at the Cancer Institute, Chennai in 1956

  1. Mineral mining machines

    Energy Technology Data Exchange (ETDEWEB)

    Mc Gaw, B H

    1984-01-01

    A machine for mining minerals is patented. It is a cutter loader with a drum actuating element of the worm type equipped with a multitude of cutting teeth reinforced with tungsten carbide. A feature of the patented machine is that all of the cutting teeth and holders on the drum have the identical design. This is achieved through selecting a slant angle for the cutting teeth which is the mean between the slant angle of the conventional radial teeth and the slant angle of the advance teeth. This, in turn, is provided thanks to the corresponding slant of the holders relative to the drum and (or) the slant of the cutting part of the teeth relative to their stems. Thus, the advance teeth projecting beyond the surface of the drum on the face side and providing upper and lateral clearances have the same angle of attack as the radial teeth, that is, from 20 to 35 degrees. A series of modifications of the cutting teeth is patented. One of the designs allows the cutting tooth to occupy a varying position relative to the drum, from the conventional vertical to an inverted, axially projecting position. In the last case the tooth in the extraction process provides the upper and lateral clearances for the drum on the face side. Among the different modifications of the cutting teeth, a design is proposed which provides for the presence of a stem which is shaped like a truncated cone. This particular stem is designed for use jointly with a wedge which unfastens the teeth and is placed in a holder. The latter is completed in a transverse slot thanks to which the rear end of the stem is compressed, which simplifies replacement of a tooth. Channels are provided in the patented machine for feeding water to the worm spiral, the holders and the cutting teeth themselves in order to deal with dust.

  2. Operational Experience with a Cryogenic Axial-Centrifugal Compressor

    CERN Document Server

    Decker, L; Löhlein, K; Purtschert, W; Ziegler, B L; Lebrun, P; Tavian, L; Brunovsky, I; Tucek, L

    1998-01-01

    The Large Hadron Collider (LHC), presently under construction at CERN, requires large refrigeration capacity at 1.8 K. Compression of gaseous helium at cryogenic temperatures is therefore inevitable. Together with subcontractors, Linde Kryotechnik has developed a prototype machine. This unit is based on a cryogenic axial-centrifugal compressor, running on ceramic ball bearings and driven by a variable-frequency electrical motor operating at ambient temperature. Integrated in a test facility for superconducting magnets the machine has been commissioned without major problems and successfully gone through the acceptance test in autumn 1995. Subsequent steps were initiated to improve efficiency of this prototype. This paper describes operating experience gained so far and reports on measured performance prior to and after constructional modifications.

  3. Machine testning

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This document is used in connection with a laboratory exercise of 3 hours duration as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The exercise includes a series of tests carried out by the student on a conventional and a numerically controled lathe, respectively. This document...

  4. Machine rates for selected forest harvesting machines

    Science.gov (United States)

    R.W. Brinker; J. Kinard; Robert Rummer; B. Lanford

    2002-01-01

    Very little new literature has been published on the subject of machine rates and machine cost analysis since 1989 when the Alabama Agricultural Experiment Station Circular 296, Machine Rates for Selected Forest Harvesting Machines, was originally published. Many machines discussed in the original publication have undergone substantial changes in various aspects, not...

  5. Simulation of magnetic induction distribution in a coaxial linear motor with axial and radial direction of permanent magnets magnetization

    Directory of Open Access Journals (Sweden)

    G.M. Golenkov

    2014-03-01

    Full Text Available The paper presents results of computer simulation and experimental study of magnetic induction distribution in a coaxial linear motor air gap throughout the length of the runner active part at different heights of the air gap between the runner and the inductor magnetic core for motors with axial and radial direction of the permanent magnets magnetization.

  6. Electron angular distribution axial channeling

    International Nuclear Information System (INIS)

    Khokonov, A.Kh.; Khokonov, M.Kh.

    1989-01-01

    Angular distributions of ultra-relativistic electrons are calculated in the assumption about presence of statistical equilibrium. Analysis is based on numerical solution of Fokker-Planck type kinetic equation. It is shown that in contrast to case of amorphous medium, the multiple scattering at axial channeling of negative particles results in self-focusing of the initial beam particles and due to it number of electrons moving at an angles to the chain, which are smaller, than critical angle of channeling, may increase by several times as compared to the initial one

  7. Electric machines

    CERN Document Server

    Gross, Charles A

    2006-01-01

    BASIC ELECTROMAGNETIC CONCEPTSBasic Magnetic ConceptsMagnetically Linear Systems: Magnetic CircuitsVoltage, Current, and Magnetic Field InteractionsMagnetic Properties of MaterialsNonlinear Magnetic Circuit AnalysisPermanent MagnetsSuperconducting MagnetsThe Fundamental Translational EM MachineThe Fundamental Rotational EM MachineMultiwinding EM SystemsLeakage FluxThe Concept of Ratings in EM SystemsSummaryProblemsTRANSFORMERSThe Ideal n-Winding TransformerTransformer Ratings and Per-Unit ScalingThe Nonideal Three-Winding TransformerThe Nonideal Two-Winding TransformerTransformer Efficiency and Voltage RegulationPractical ConsiderationsThe AutotransformerOperation of Transformers in Three-Phase EnvironmentsSequence Circuit Models for Three-Phase Transformer AnalysisHarmonics in TransformersSummaryProblemsBASIC MECHANICAL CONSIDERATIONSSome General PerspectivesEfficiencyLoad Torque-Speed CharacteristicsMass Polar Moment of InertiaGearingOperating ModesTranslational SystemsA Comprehensive Example: The ElevatorP...

  8. Charging machine

    International Nuclear Information System (INIS)

    Medlin, J.B.

    1976-01-01

    A charging machine for loading fuel slugs into the process tubes of a nuclear reactor includes a tubular housing connected to the process tube, a charging trough connected to the other end of the tubular housing, a device for loading the charging trough with a group of fuel slugs, means for equalizing the coolant pressure in the charging trough with the pressure in the process tubes, means for pushing the group of fuel slugs into the process tube and a latch and a seal engaging the last object in the group of fuel slugs to prevent the fuel slugs from being ejected from the process tube when the pusher is removed and to prevent pressure liquid from entering the charging machine. 3 claims, 11 drawing figures

  9. Axially alignable nuclear fuel pellets

    International Nuclear Information System (INIS)

    Johansson, E.B.; Klahn, D.H.; Marlowe, M.O.

    1978-01-01

    An axially alignable nuclear fuel pellet of the type stacked in end-to-end relationship within a tubular cladding is described. Fuel cladding failures can occur at pellet interface locations due to mechanical interaction between misaligned fuel pellets and the cladding. Mechanical interaction between the cladding and the fuel pellets loads the cladding and causes increased cladding stresses. Nuclear fuel pellets are provided with an end structure that increases plastic deformation of the pellets at the interface between pellets so that lower alignment forces are required to straighten axially misaligned pellets. Plastic deformation of the pellet ends results in less interactions beween the cladding and the fuel pellets and significantly lowers cladding stresses. The geometry of pellets constructed according to the invention also reduces alignment forces required to straighten fuel pellets that are tilted within the cladding. Plastic deformation of the pellets at the pellet interfaces is increased by providing pellets with at least one end face having a centrally-disposed raised area of convex shape so that the mean temperature and shear stress of the contact area is higher than that of prior art pellets

  10. PWR AXIAL BURNUP PROFILE ANALYSIS

    International Nuclear Information System (INIS)

    J.M. Acaglione

    2003-01-01

    The purpose of this activity is to develop a representative ''limiting'' axial burnup profile for pressurized water reactors (PWRs), which would encompass the isotopic axial variations caused by different assembly irradiation histories, and produce conservative isotopics with respect to criticality. The effect that the low burnup regions near the ends of spent fuel have on system reactivity is termed the ''end-effect''. This calculation will quantify the end-effects associated with Pressurized Water Reactor (PWR) fuel assemblies emplaced in a hypothetical 21 PWR waste package. The scope of this calculation covers an initial enrichment range of 3.0 through 5.0 wt% U-235 and a burnup range of 10 through 50 GWd/MTU. This activity supports the validation of the process for ensuring conservative generation of spent fuel isotopics with respect to criticality safety applications, and the use of burnup credit for commercial spent nuclear fuel. The intended use of these results will be in the development of PWR waste package loading curves, and applications involving burnup credit. Limitations of this evaluation are that the limiting profiles are only confirmed for use with the B andW 15 x 15 fuel assembly design. However, this assembly design is considered bounding of all other typical commercial PWR fuel assembly designs. This calculation is subject to the Quality Assurance Requirements and Description (QARD) because this activity supports investigations of items or barriers on the Q-list (YMP 2001)

  11. Exact axially symmetric galactic dynamos

    Science.gov (United States)

    Henriksen, R. N.; Woodfinden, A.; Irwin, J. A.

    2018-05-01

    We give a selection of exact dynamos in axial symmetry on a galactic scale. These include some steady examples, at least one of which is wholly analytic in terms of simple functions and has been discussed elsewhere. Most solutions are found in terms of special functions, such as associated Lagrange or hypergeometric functions. They may be considered exact in the sense that they are known to any desired accuracy in principle. The new aspect developed here is to present scale-invariant solutions with zero resistivity that are self-similar in time. The time dependence is either a power law or an exponential factor, but since the geometry of the solution is self-similar in time we do not need to fix a time to study it. Several examples are discussed. Our results demonstrate (without the need to invoke any other mechanisms) X-shaped magnetic fields and (axially symmetric) magnetic spiral arms (both of which are well observed and documented) and predict reversing rotation measures in galaxy haloes (now observed in the CHANG-ES sample) as well as the fact that planar magnetic spirals are lifted into the galactic halo.

  12. Genesis machines

    CERN Document Server

    Amos, Martyn

    2014-01-01

    Silicon chips are out. Today's scientists are using real, wet, squishy, living biology to build the next generation of computers. Cells, gels and DNA strands are the 'wetware' of the twenty-first century. Much smaller and more intelligent, these organic computers open up revolutionary possibilities. Tracing the history of computing and revealing a brave new world to come, Genesis Machines describes how this new technology will change the way we think not just about computers - but about life itself.

  13. Numerical simulation of the tip clearance flow in axial turbomachinery; Numerische Simulation der Stroemung im radialen Schaufelspalt axialer Turbomaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Melake, A [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Koeln (Germany). Inst. fuer Antriebstechnik

    1997-12-31

    A computer program has been developed to calculate the three-dimensional tip leakage flow in axial turbomachinery based on the Navier-Stokes equation. This program has been applied to investigate the leakage flow within the gap between the blade fip and casing in an annular compressor cascade. A block structured computational mesh has been used in order to resolve the flow details within the gap and the passage flow. Flow characteristics like boundary layer separation, vortex genesis and interaction of the leakage flow with the secondary flow have been investigated and compared with existing experimental data. By varying the incidence angle and the tip gap the above mentioned flow phenomena have been analysed in an annular compressor cascade and a shrouded propfan rotor respectively. Furthermore, the relationship between the total pressure loss, the axial velocity deficit and the divergence of the tip leakage vortex has been investigated. Streamlines, limited streamlines and the critical point theory have been used extensively to analyse the boundary layer separation on the casing and its roll up to form the tip clearance vortex. (orig.). 59 figs., 3 tabs., 110 refs. [Deutsch] Es wurde ein Rechenprogramm zur Berechnung der dreidimensionalen Spaltstroemung im radialen Schaufelspalt axialer Turbomaschinen auf der Basis der Navier-Stokes`schen Gleichungen entwickelt und angewendet. Um die Stroemung innerhalb des Spaltes und der Schaufelpassage besser aufloesen zu koennen, wurde eine blockstrukturierte Netztopologie verwendet. Stroemungseigenschaften wie Grenzschichtabloesung, Entstehung des Spaltwirbels, Interaktion der Spaltstroemung mit der Sekundaerstroemung werden untersucht und mit vorhandenen experimentellen Daten verglichen. Im weiteren werden durch Variation der Inzidenz und der Spaltweite die oben genannten Stroemungsphaenomene an einem axialen Verdichterringgitter und an einem ummantelten Propfan analysiert. Ferner werden die Korrelation zwischen

  14. Molecular machines with bio-inspired mechanisms.

    Science.gov (United States)

    Zhang, Liang; Marcos, Vanesa; Leigh, David A

    2018-02-26

    The widespread use of molecular-level motion in key natural processes suggests that great rewards could come from bridging the gap between the present generation of synthetic molecular machines-which by and large function as switches-and the machines of the macroscopic world, which utilize the synchronized behavior of integrated components to perform more sophisticated tasks than is possible with any individual switch. Should we try to make molecular machines of greater complexity by trying to mimic machines from the macroscopic world or instead apply unfamiliar (and no doubt have to discover or invent currently unknown) mechanisms utilized by biological machines? Here we try to answer that question by exploring some of the advances made to date using bio-inspired machine mechanisms.

  15. Criticality effects of longitudinal gaps in poison for storage/transport casks

    International Nuclear Information System (INIS)

    Wells, A.H.

    1985-01-01

    A series of criticality calculations was performed with the AMPX/KENO system to determine the sensitivity of the NAC S/T cask 31 assembly basket, which is optimized for a design-basis fuel enrichment of 3.7 wt % 235 U, to axial gaps in the boron neutron poison. The results of these calculations show that axial gaps in the boron cause no statistically detectable change in k/sub eff/ until a minimum gap size is reached. The minimum gap size to change k/sub eff/ is dependent on the basket segment length, because a longer segment length results in fewer gaps for a given active fuel length. Longer segment lengths are less sensitive to gaps in the neutron poison. A typical segment length of 12 to 18 in. is projected for a casting of aluminum/boron alloy, indicating that axial gaps in the neutron poison of 1 in. would be acceptable. This gap thickness is much greater than the intersegment gap produced by modern casting techniques. The investigation described here demonstrated that an axial gap in neutron poison is acceptable for basket castings of large storage/transport casks. A precedent for such gaps is the NLI-6502 cask, so a cask basket with intersegment gaps should be licensable

  16. Estimation of modes frictions and greasing in bearing axial hanging of locomotives

    Directory of Open Access Journals (Sweden)

    V.N. Аstаkhоv

    2012-04-01

    Full Text Available Dependence is considered between the size of relative diametral gap and descriptions of work of the motor-axial bearing on the different rates of movement of diesel engine: by the type of the mode of greasing, thickness lubricating layer, by the coefficient of friction and intensity of wear.

  17. Cleaning and can end chamfering special machine MSCS-04

    International Nuclear Information System (INIS)

    Negulescu, D.; Rusu, A.; Dragomir, I.; Turcanu, V.; Bailescu, V.; Burcea, Gh.; Chitu, I.

    2001-01-01

    The MSCS-04 machine executes cleaning and can end chamfering of the CANDU 6 fuel element can through the following technologic chain: - manual positioning of the workpiece in the transporter feeding location; - the transport of the workpiece in front of the cleaning machine and workpiece orientation checking; - automatic loading of the workpiece in the cleaning machine; - bonding the workpiece in the cleaning machine; - cleaning the ends of the workpiece with graphite dust aspiration; - automatic disconnection of the workpiece from the cleaning machine; - automatic unloading of the cleaning machine; - disposal of the workpiece on the transporter in front of cleaning machine; workpiece's transport in front of the chamfering machine; - automatic checking of the workpiece orientation; - automatic loading of the workpiece in the chamfering machine; - axial positioning and bounding of the workpiece in the chamfering machine; chamfering the workpiece's ends with graphite dust and splinter aspiration; - disconnecting the workpiece from the chamfering machine; - automatic unloading of the workpiece from the chamfering machine with splinter blow from the workpiece interior; - workpiece disposal on transporter and the piece transport to the outlet. Details about the technological system, transport system, manipulators, cleaning and chamfering machines are given. Novel elements are highlighted and the technical characteristics are presented

  18. Investigation of permanent magnet machines for downhole applications: Design, prototype and testing of a flux-switching permanent magnet machine

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Anyuan

    2011-01-15

    The current standard electrical downhole machine is the induction machine which is relatively inefficient. Permanent magnet (PM) machines, having higher efficiencies, higher torque densities and smaller volumes, have widely employed in industrial applications to replace conventional machines, but few have been developed for downhole applications due to the high ambient temperatures in deep wells and the low temperature stability of PM materials over time. Today, with the development of variable speed drives and the applications of high temperature magnet materials, it is increasingly interesting for oil and gas industries to develop PM machines for downhole applications. Recently, some PM machines applications have been presented for downhole applications, which are normally addressed on certain specific downhole case. In this thesis the focus has been put on the performance investigation of different PM machines for general downhole cases, in which the machine outer diameter is limited to be small by well size, while the machine axial length may be relatively long. The machine reliability is the most critical requirement while high torque density and high efficiency are also desirable. The purpose is to understand how the special constraints in downhole condition affect the performances of different machines. First of all, three basic machine concepts, which are the radial, axial and transverse flux machines, are studied in details by analytical method. Their torque density, efficiency, power factor and power capability are investigated with respect to the machine axial length and pole number. The presented critical performance comparisons of the machines provide an indication of machines best suitable with respect to performance and size for downhole applications. Conventional radial flux permanent magnet (RFPM) machines with the PMs on the rotor can provide high torque density and high efficiency. This type of machine has been suggested for several different

  19. Axial vector mass spectrum and mixing angles

    International Nuclear Information System (INIS)

    Caffarelli, R.V.; Kang, K.

    1976-01-01

    Spectral sum rules of the axial-vector current and axial-vector current-pseudoscalar field are used to study the axial-vector mass spectrum and mixing angles, as well as the decay constants and mixing angles of the pseudoscalar mesons. In general, the result is quite persuasive for the existence of the Jsup(PC) = 1 ++ multiplet in which one has a canonical D-E mixing. (Auth.)

  20. Centrifugal and axial compressor control

    CERN Document Server

    McMillan, Gregory K

    2009-01-01

    Control engineers, mechanical engineers and mechanical technicians will learn how to select the proper control systems for axial and centrifugal compressors for proper throughput and surge control, with a particular emphasis on surge control. Readers will learn to understand the importance of transmitter speed, digital controller sample time, and control valve stroking time in helping to prevent surge. Engineers and technicians will find this book to be a highly valuable guide on compressor control schemes and the importance of mitigating costly and sometimes catastrophic surge problems. It can be used as a self-tutorial guide or in the classroom with the book's helpful end-of-chapter questions and exercises and sections for keeping notes.

  1. Axial channeling in electron diffraction

    International Nuclear Information System (INIS)

    Ichimiya, A.; Lehmpfuhl, G.

    1978-01-01

    Kossel patterns from Silicon and Niobium were obtained with a convergent electron beam. An intensity maximum in the direction of the zone axes [001] and [111] of Nb was interpreted as axial channeling. The intensity distribution in Kossel patterns was calculated by means of the Bloch wave picture of the dynamical theory of electron diffraction. Particularly zone axis patterns were calculated for different substance-energy combinations and they were compared with experimental observations. The intensity distribution in the calculated Kossel patterns was very sensitive to the model of absorption and it was found that a treatment of the absorption close to the model of Humphreys and Hirsch [Phil. Mag. 18, 115 (1968)] gave the best agreement with the experimental observations. Furthermore it is shown which Bloch waves are important for the intensity distribution in the Kossel patterns, how they are absorbed and how they change with energy. (orig.) [de

  2. Axial channeling of uttrarelativistic electrons

    Energy Technology Data Exchange (ETDEWEB)

    Telegin, V.I.; Khokonov, M.Kh. (Moskovskij Gosudarstvennyj Univ. (USSR). Nauchno-Issledovatel' skij Inst. Yadernoj Fiziki)

    1982-07-01

    The dynamics of motion of ultrarelativistic electrons under axial channeling conditions is investigated. The analysis is based on the solution of the kinetic equation obtained recently by Beloshitsky and Kumakhov. The particle dechanneling function is investigated as depending on the type of a crystal, particle energy and angle of entrance into the single crystal. It is found that for most of the beam the major diffusion mechanism is scattering by electrons. It is shown that an optimal depth range exists for which the fraction of channeled particles sharply increases at the expense of the quasi-channeled particles. In a number of cases the dechanneling length for crystals with high atomic numbers may be greater than that of light elements.

  3. Axial channeling of uttrarelativistic electrons

    International Nuclear Information System (INIS)

    Telegin, V.I.; Khokonov, M.Kh.

    1982-01-01

    The dynamics of motion of ultrarelativistic electrons under axial channeling conditions is investigated. The analysis is based on the solution of the kinetic equation obtained recently by Beloshitsky and Kumakhov. The particle dechanneling function is investigated as depending on the type of a crystal, particle energy and angle of entrance into the single crystal. It is found that for most of the beam the major diffusion mechanism is scattering by electrons. It is shown that an optimal depth range exists for which the fraction of channeled particles sharply increases at the expense of the quasi-channeled particles. In a number of cases the dechanneling length for crystals with high atomic numbers may be greater than that of light elements

  4. Bone Disease in Axial Spondyloarthritis.

    Science.gov (United States)

    Van Mechelen, Margot; Gulino, Giulia Rossana; de Vlam, Kurt; Lories, Rik

    2018-05-01

    Axial spondyloarthritis is a chronic inflammatory skeletal disorder with an important burden of disease, affecting the spine and sacroiliac joints and typically presenting in young adults. Ankylosing spondylitis, diagnosed by the presence of structural changes to the skeleton, is the prototype of this disease group. Bone disease in axial spondyloarthritis is a complex phenomenon with the coexistence of bone loss and new bone formation, both contributing to the morbidity of the disease, in addition to pain caused by inflammation. The skeletal structural changes respectively lead to increased fracture risk and to permanent disability caused by ankylosis of the sacroiliac joints and the spine. The mechanism of this new bone formation leading to ankylosis is insufficiently known. The process appears to originate from entheses, specialized structures that provide a transition zone in which tendon and ligaments insert into the underlying bone. Growth factor signaling pathways such as bone morphogenetic proteins, Wnts, and Hedgehogs have been identified as molecular drivers of new bone formation, but the relationship between inflammation and activation of these pathways remains debated. Long-standing control of inflammation appears necessary to avoid ankylosis. Recent evidence and concepts suggest an important role for biomechanical factors in both the onset and progression of the disease. With regard to new bone formation, these processes can be understood as ectopic repair responses secondary to inflammation-induced bone loss and instability. In this review, we discuss the clinical implications of the skeletal changes as well as the underlying molecular mechanisms, the relation between inflammation and new bone formation, and the potential role of biomechanical stress.

  5. Resolution of axial shear strain elastography

    International Nuclear Information System (INIS)

    Thitaikumar, Arun; Righetti, Raffaella; Krouskop, Thomas A; Ophir, Jonathan

    2006-01-01

    The technique of mapping the local axial component of the shear strain due to quasi-static axial compression is defined as axial shear strain elastography. In this paper, the spatial resolution of axial shear strain elastography is investigated through simulations, using an elastically stiff cylindrical lesion embedded in a homogeneously softer background. Resolution was defined as the smallest size of the inclusion for which the strain value at the inclusion/background interface was greater than the average of the axial shear strain values at the interface and inside the inclusion. The resolution was measured from the axial shear strain profile oriented at 45 0 to the axis of beam propagation, due to the absence of axial shear strain along the normal directions. The effects of the ultrasound system parameters such as bandwidth, beamwidth and transducer element pitch along with signal processing parameters such as correlation window length (W) and axial shift (ΔW) on the estimated resolution were investigated. The results show that the resolution (at 45 0 orientation) is determined by the bandwidth and the beamwidth. However, the upper bound on the resolution is limited by the larger of the beamwidth and the window length, which is scaled inversely to the bandwidth. The results also show that the resolution is proportional to the pitch and not significantly affected by the axial window shift

  6. Origin of axial current in scyllac

    International Nuclear Information System (INIS)

    Sugisaki, K.

    1975-12-01

    The origin of the axial current observed in Scyllac (a high beta stellarator experiment) is discussed. A shaped coil and/or helical winding produce rotational transform which links magnetic lines of force to the plasma column and the axial current is induced electromagnetically. This phenomenon is inherent in a pulsed high-beta stellarator. The rotational transform produced by the induced axial current is much smaller than that associated with the l = 1, 0 equilibrium fields. The effect of the axial current on the equilibrium and stability of the plasma column is thus small. It is also shown that the magnetic field shear near a plasma surface is very strong

  7. Radial and axial compression of pure electron

    International Nuclear Information System (INIS)

    Park, Y.; Soga, Y.; Mihara, Y.; Takeda, M.; Kamada, K.

    2013-01-01

    Experimental studies are carried out on compression of the density distribution of a pure electron plasma confined in a Malmberg-Penning Trap in Kanazawa University. More than six times increase of the on-axis density is observed under application of an external rotating electric field that couples to low-order Trivelpiece-Gould modes. Axial compression of the density distribution with the axial length of a factor of two is achieved by controlling the confining potential at both ends of the plasma. Substantial increase of the axial kinetic energy is observed during the axial compression. (author)

  8. Representational Machines

    DEFF Research Database (Denmark)

    Photography not only represents space. Space is produced photographically. Since its inception in the 19th century, photography has brought to light a vast array of represented subjects. Always situated in some spatial order, photographic representations have been operatively underpinned by social...... to the enterprises of the medium. This is the subject of Representational Machines: How photography enlists the workings of institutional technologies in search of establishing new iconic and social spaces. Together, the contributions to this edited volume span historical epochs, social environments, technological...... possibilities, and genre distinctions. Presenting several distinct ways of producing space photographically, this book opens a new and important field of inquiry for photography research....

  9. Shear machines

    International Nuclear Information System (INIS)

    Astill, M.; Sunderland, A.; Waine, M.G.

    1980-01-01

    A shear machine for irradiated nuclear fuel elements has a replaceable shear assembly comprising a fuel element support block, a shear blade support and a clamp assembly which hold the fuel element to be sheared in contact with the support block. A first clamp member contacts the fuel element remote from the shear blade and a second clamp member contacts the fuel element adjacent the shear blade and is advanced towards the support block during shearing to compensate for any compression of the fuel element caused by the shear blade (U.K.)

  10. Thermal models of pulse electrochemical machining

    International Nuclear Information System (INIS)

    Kozak, J.

    2004-01-01

    Pulse electrochemical machining (PECM) provides an economical and effective method for machining high strength, heat-resistant materials into complex shapes such as turbine blades, die, molds and micro cavities. Pulse Electrochemical Machining involves the application of a voltage pulse at high current density in the anodic dissolution process. Small interelectrode gap, low electrolyte flow rate, gap state recovery during the pulse off-times lead to improved machining accuracy and surface finish when compared with ECM using continuous current. This paper presents a mathematical model for PECM and employs this model in a computer simulation of the PECM process for determination of the thermal limitation and energy consumption in PECM. The experimental results and discussion of the characteristics PECM are presented. (authors)

  11. Electricity of machine tool

    International Nuclear Information System (INIS)

    Gijeon media editorial department

    1977-10-01

    This book is divided into three parts. The first part deals with electricity machine, which can taints from generator to motor, motor a power source of machine tool, electricity machine for machine tool such as switch in main circuit, automatic machine, a knife switch and pushing button, snap switch, protection device, timer, solenoid, and rectifier. The second part handles wiring diagram. This concludes basic electricity circuit of machine tool, electricity wiring diagram in your machine like milling machine, planer and grinding machine. The third part introduces fault diagnosis of machine, which gives the practical solution according to fault diagnosis and the diagnostic method with voltage and resistance measurement by tester.

  12. Environmentally Friendly Machining

    CERN Document Server

    Dixit, U S; Davim, J Paulo

    2012-01-01

    Environment-Friendly Machining provides an in-depth overview of environmentally-friendly machining processes, covering numerous different types of machining in order to identify which practice is the most environmentally sustainable. The book discusses three systems at length: machining with minimal cutting fluid, air-cooled machining and dry machining. Also covered is a way to conserve energy during machining processes, along with useful data and detailed descriptions for developing and utilizing the most efficient modern machining tools. Researchers and engineers looking for sustainable machining solutions will find Environment-Friendly Machining to be a useful volume.

  13. Insulation assembly for electric machine

    Science.gov (United States)

    Rhoads, Frederick W.; Titmuss, David F.; Parish, Harold; Campbell, John D.

    2013-10-15

    An insulation assembly is provided that includes a generally annularly-shaped main body and at least two spaced-apart fingers extending radially inwards from the main body. The spaced-apart fingers define a gap between the fingers. A slot liner may be inserted within the gap. The main body may include a plurality of circumferentially distributed segments. Each one of the plurality of segments may be operatively connected to another of the plurality of segments to form the continuous main body. The slot liner may be formed as a single extruded piece defining a plurality of cavities. A plurality of conductors (extendable from the stator assembly) may be axially inserted within a respective one of the plurality of cavities. The insulation assembly electrically isolates the conductors in the electric motor from the stator stack and from other conductors.

  14. Machine Protection

    CERN Document Server

    Schmidt, R

    2014-01-01

    The protection of accelerator equipment is as old as accelerator technology and was for many years related to high-power equipment. Examples are the protection of powering equipment from overheating (magnets, power converters, high-current cables), of superconducting magnets from damage after a quench and of klystrons. The protection of equipment from beam accidents is more recent. It is related to the increasing beam power of high-power proton accelerators such as ISIS, SNS, ESS and the PSI cyclotron, to the emission of synchrotron light by electron–positron accelerators and FELs, and to the increase of energy stored in the beam (in particular for hadron colliders such as LHC). Designing a machine protection system requires an excellent understanding of accelerator physics and operation to anticipate possible failures that could lead to damage. Machine protection includes beam and equipment monitoring, a system to safely stop beam operation (e.g. dumping the beam or stopping the beam at low energy) and an ...

  15. Stochastic quantization for the axial model

    International Nuclear Information System (INIS)

    Farina, C.; Montani, H.; Albuquerque, L.C.

    1991-01-01

    We use bosonization ideas to solve the axial model in the stochastic quantization framework. We obtain the fermion propagator of the theory decoupling directly the Langevin equation, instead of the Fokker-Planck equation. In the Appendix we calculate explicitly the anomalous divergence of the axial-vector current by using a regularization that does not break the Markovian character of the stochastic process

  16. Health and imaging outcomes in axial spondyloarthritis

    NARCIS (Netherlands)

    Machado, P.M.

    2016-01-01

    This thesis focuses on the assessment and monitoring of health and imaging outcomes in axial spondyloarthritis (SpA) and the relationship between these outcomes. Four major contributions to the understanding and management of axial SpA were made: 1) the improvement and facilitation of the assessment

  17. Analysis of machining and machine tools

    CERN Document Server

    Liang, Steven Y

    2016-01-01

    This book delivers the fundamental science and mechanics of machining and machine tools by presenting systematic and quantitative knowledge in the form of process mechanics and physics. It gives readers a solid command of machining science and engineering, and familiarizes them with the geometry and functionality requirements of creating parts and components in today’s markets. The authors address traditional machining topics, such as: single and multiple point cutting processes grinding components accuracy and metrology shear stress in cutting cutting temperature and analysis chatter They also address non-traditional machining, such as: electrical discharge machining electrochemical machining laser and electron beam machining A chapter on biomedical machining is also included. This book is appropriate for advanced undergraduate and graduate mechani cal engineering students, manufacturing engineers, and researchers. Each chapter contains examples, exercises and their solutions, and homework problems that re...

  18. Machine Protection

    International Nuclear Information System (INIS)

    Schmidt, R

    2014-01-01

    The protection of accelerator equipment is as old as accelerator technology and was for many years related to high-power equipment. Examples are the protection of powering equipment from overheating (magnets, power converters, high-current cables), of superconducting magnets from damage after a quench and of klystrons. The protection of equipment from beam accidents is more recent. It is related to the increasing beam power of high-power proton accelerators such as ISIS, SNS, ESS and the PSI cyclotron, to the emission of synchrotron light by electron–positron accelerators and FELs, and to the increase of energy stored in the beam (in particular for hadron colliders such as LHC). Designing a machine protection system requires an excellent understanding of accelerator physics and operation to anticipate possible failures that could lead to damage. Machine protection includes beam and equipment monitoring, a system to safely stop beam operation (e.g. dumping the beam or stopping the beam at low energy) and an interlock system providing the glue between these systems. The most recent accelerator, the LHC, will operate with about 3 × 10 14 protons per beam, corresponding to an energy stored in each beam of 360 MJ. This energy can cause massive damage to accelerator equipment in case of uncontrolled beam loss, and a single accident damaging vital parts of the accelerator could interrupt operation for years. This article provides an overview of the requirements for protection of accelerator equipment and introduces the various protection systems. Examples are mainly from LHC, SNS and ESS

  19. Axial anomalies of Lifshitz fermions

    CERN Document Server

    Bakas, Ioannis

    2011-01-01

    We compute the axial anomaly of a Lifshitz fermion theory with anisotropic scaling z=3 which is minimally coupled to geometry in 3+1 space-time dimensions. We find that the result is identical to the relativistic case using path integral methods. An independent verification is provided by showing with spectral methods that the eta-invariant of the Dirac and Lifshitz fermion operators in three dimensions are equal. Thus, by the integrated form of the anomaly, the index of the Dirac operator still accounts for the possible breakdown of chiral symmetry in non-relativistic theories of gravity. We apply this framework to the recently constructed gravitational instanton backgrounds of Horava-Lifshitz theory and find that the index is non-zero provided that the space-time foliation admits leaves with harmonic spinors. Using Hitchin's construction of harmonic spinors on Berger spheres, we obtain explicit results for the index of the fermion operator on all such gravitational instanton backgrounds with SU(2)xU(1) isom...

  20. Design and development of remotely operated coolant channel cutting machine

    International Nuclear Information System (INIS)

    Suthar, R.L.; Sinha, A.K.; Srikrishnamurty, G.

    1994-01-01

    One of the coolant tubes of Narora Atomic Power Station (NAPS) reactor needs to be removed. To remove a coolant tube, four cutting operations, (liner tube cutting, end-fitting cutting, machining of seal weld of bellow ring and finally coolant tube cutting) are required to be carried out. A remotely operated cutting machine to carry out all these operations has been designed and developed by Central Workshops. This machine is able to cut at the exact location because of numerically controlled axial and radial travel of tool. Only by changing the tool head and tool holder, same machine can be used for various types of cutting/machining operations. This report details the design, manufacture, assembly and testing work done on the machine. (author). 4 figs

  1. Numerical Investigation of Pressure Fluctuation Characteristics in a Centrifugal Pump with Variable Axial Clearance

    Directory of Open Access Journals (Sweden)

    Lei Cao

    2016-01-01

    Full Text Available Clearance flows in the sidewall gaps of centrifugal pumps are unsteady as well as main flows in the volute casing and impeller, which may cause vibration and noise, and the corresponding pressure fluctuations are related to the axial clearance size. In this paper, unsteady numerical simulations were conducted to predict the unsteady flows within the entire flow passage of a centrifugal pump operating in the design condition. Pressure fluctuation characteristics in the volute casing, impeller, and sidewall gaps were investigated with three axial clearance sizes. Results show that an axial clearance variation affects the pressure fluctuation characteristics in each flow domain by different degree. The greatest pressure fluctuation occurs at the blade pressure surface and is almost not influenced by the axial clearance variation which has a certainly effect on the pressure fluctuation characteristics around the tongue. The maximum pressure fluctuation amplitude in the sidewall gaps is larger than that in the volute casing, and different spectrum characteristics show up in the three models due to the interaction between the clearance flow and the main flow as well as the rotor-stator interaction. Therefore, clearance flow should be taken into consideration in the hydraulic design of centrifugal pumps.

  2. Machine terms dictionary

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1979-04-15

    This book gives descriptions of machine terms which includes machine design, drawing, the method of machine, machine tools, machine materials, automobile, measuring and controlling, electricity, basic of electron, information technology, quality assurance, Auto CAD and FA terms and important formula of mechanical engineering.

  3. OptiCentric lathe centering machine

    Science.gov (United States)

    Buß, C.; Heinisch, J.

    2013-09-01

    High precision optics depend on precisely aligned lenses. The shift and tilt of individual lenses as well as the air gap between elements require accuracies in the single micron regime. These accuracies are hard to meet with traditional assembly methods. Instead, lathe centering can be used to machine the mount with respect to the optical axis. Using a diamond turning process, all relevant errors of single mounted lenses can be corrected in one post-machining step. Building on the OptiCentric® and OptiSurf® measurement systems, Trioptics has developed their first lathe centering machines. The machine and specific design elements of the setup will be shown. For example, the machine can be used to turn optics for i-line steppers with highest precision.

  4. Electrical machining method of insulating ceramics

    International Nuclear Information System (INIS)

    Fukuzawa, Y.; Mohri, N.; Tani, T.

    1999-01-01

    This paper describes a new electrical discharge machining method for insulating ceramics using an assisting electrode with either a sinking electrical discharge machine or a wire electrical discharge machine. In this method, the metal sheet or mesh is attached to the ceramic surface as an assisting material for the discharge generation around the insulator surface. When the machining condition changes from the attached material to the workpiece, a cracked carbon layer is formed on the workpiece surface. As this layer has an electrical conductivity, electrical discharge occurs in working oil between the tool electrode and the surface of the workpiece. The carbon is formed from the working oil during this electrical discharge. Even after the material is machined, an electrical discharge occurs in the gap region between the tool electrode and the ceramic because an electrically conductive layer is generated continuously. Insulating ceramics can be machined by the electrical discharge machining method using the above mentioned surface modification phenomenon. In this paper the authors show a machined example demonstrating that the proposed method is available for machining a complex shape on insulating ceramics. Copyright (1999) AD-TECH - International Foundation for the Advancement of Technology Ltd

  5. Evaluation of the inner wall axial cracks of steam generator tubes by eddy current test

    International Nuclear Information System (INIS)

    Hur, Do Haeng; Choi, Myung Sik; Lee, Doek Hyun; Han, Jung Ho

    2001-01-01

    For the enhancement of ECT reliability on the primary water stress corrosion cracks of nuclear steam generator tubes, it is important to comprehend the signal characteristics on crack morphology and to select an appropriate probe type. In this paper, the sizing accuracy and the detectability for the inner wall axial cracks of tubes were quantitatively evaluated using the electric discharge machined notches and the corrosion cracks which were developed on the operating steam generator tubes. The difference of eddy current signal characteristics between pancake and axial coil were also investigated. The results obtained from this study provide a useful information for more precise evaluation on the inner wall axial cracks of steam generator tubes.

  6. Evaluation of Eddy Current Signals from the Inner Wall Axial Cracks of Steam Generator Tubes

    International Nuclear Information System (INIS)

    Choi, Myung Sik; Hur, Do Haeng; Lee, Doek Hyun; Han, Jung Ho; Park, Jung Am

    2001-01-01

    For the enhancement of ECT reliability on the primary water stress corrosion cracks of nuclear steam generator tubes, of which the occurrence is on the increase, it is important to comprehend the signal characteristics on crack morphology and to select an appropriate probe type. In this paper, the sizing accuracy and the detectability for the inner wall axial cracks of tubes were quantitatively evaluated using the following specimens: the electric discharge machined notches and the corrosion cracks which were developed on the operating steam generator tubes. The difference of eddy current signal characteristics between pancake and axial coil were also Investigated. The results obtained from this study provide a useful information for more precise evaluation on the inner wall axial tracks oi steam generator tubes

  7. Accuracy of axial depth of cut in micromilling operations - Simplified procedure and uncertainty model

    DEFF Research Database (Denmark)

    Bissacco, Giuliano

    2005-01-01

    , due to the easy breakage particularly when milling on hard materials [1]. Typical values for the errors on the control of the axial depth of cut are in the order of 50 microns, while the aimed depth of cut can be as low as 5 microns. The author has developed a machining procedure for optimal control...... of this investigation is the determination of the uncertainty of the set depth of cut, using the developed procedure, in a range of practical operating conditions and thereby the estimation of the expected accuracy of the method prior to verification of the machined parts....

  8. Ergonomics for enhancing detection of machine abnormalities.

    Science.gov (United States)

    Illankoon, Prasanna; Abeysekera, John; Singh, Sarbjeet

    2016-10-17

    Detecting abnormal machine conditions is of great importance in an autonomous maintenance environment. Ergonomic aspects can be invaluable when detection of machine abnormalities using human senses is examined. This research outlines the ergonomic issues involved in detecting machine abnormalities and suggests how ergonomics would improve such detections. Cognitive Task Analysis was performed in a plant in Sri Lanka where Total Productive Maintenance is being implemented to identify sensory types that would be used to detect machine abnormalities and relevant Ergonomic characteristics. As the outcome of this research, a methodology comprising of an Ergonomic Gap Analysis Matrix for machine abnormality detection is presented.

  9. Modernity: A new axial (era culture?

    Directory of Open Access Journals (Sweden)

    Wolfgang Schluchter

    2017-10-01

    Full Text Available The proposition of an axial age, lasting roughly from 800 to 200 B.C. and occurring in major civilizations (China, India, Near East independent of each other, first introduced by Alfred Weber and Karl Jaspers, then further developed by Robert Bellah and S. N. Eisenstadt among others, implied from the outset the question whether there has been a second axial age, leading to modernity, and if so, whether this second axial age consists in a secularization of the achievements of the first axial age. In this article it is argued that the notion of a second axial age is meaningful, but that the emergence of modernity can›t be accounted for in terms of secularization of the achievements of the first axial age. Rather, a new axial principle was institutionalized which separates the modern from the premodern world. This new principle is spelled out with reference to Hans Blumenberg, Charles Taylor and especially Max Weber. The emphasis is on the dialectics of disenchantment and the place of religion in a secular age

  10. Development of throughflow calculation code for axial flow compressors

    International Nuclear Information System (INIS)

    Kim, Ji Hwan; Kim, Hyeun Min; No, Hee Cheon

    2005-01-01

    The power conversion systems of the current HTGRs are based on closed Brayton cycle and major concern is thermodynamic performance of the axial flow helium gas turbines. Particularly, the helium compressor has some unique design challenges compared to the air-breathing compressor such as high hub-to-tip ratios throughout the machine and a large number of stages due to the physical property of the helium and thermodynamic cycle. Therefore, it is necessary to develop a design and analysis code for helium compressor that can estimate the design point and off-design performance accurately. KAIST nuclear system laboratory has developed a compressor design and analysis code by means of throughflow calculation and several loss models. This paper presents the outline of the development of a throughflow calculation code and its verification results

  11. Computer aided hydraulic design of axial flow pump impeller

    International Nuclear Information System (INIS)

    Sreedhar, B.K.; Rao, A.S.L.K.; Kumaraswamy, S.

    1994-01-01

    Pumps are the heart of any power plant and hence their design requires great attention. Computers with their potential for rapid computation can be successfully employed in the design and manufacture of these machines. The paper discusses a program developed for the hydraulic design of axial flow pump impeller. The program, written in FORTRAN 77, is interactive and performs the functions of design calculation, drafting and generation of numerical data for blade manufacture. The drafting function, which makes use of the software ACAD, is carried out automatically by means of suitable interface programs. In addition data for blade manufacture is also generated in either the x-y-z or r-θ-z system. (author). 4 refs., 3 figs

  12. A cryogenic axial-centrifugal compressor for superfluid helium refrigeration

    CERN Document Server

    Decker, L; Schustr, P; Vins, M; Brunovsky, I; Lebrun, P; Tavian, L

    1997-01-01

    CERN's new project, the Large Hadron Collider (LHC), will use superfluid helium as coolant for its high-field superconducting magnets and therefore require large capacity refrigeration at 1.8 K. This may only be achieved by subatmospheric compression of gaseous helium at cryogenic temperature. To stimulate development of this technology, CERN has procured from industry prototype Cold Compressor Units (CCU). This unit is based on a cryogenic axial-centrifugal compressor, running on ceramic ball bearings and driven by a variable-frequency electrical motor operating under low-pressure helium at ambient temperature. The machine has been commissioned and is now in operation. After describing basic constructional features of the compressor, we report on measured performance.

  13. Addiction Machines

    Directory of Open Access Journals (Sweden)

    James Godley

    2011-10-01

    Full Text Available Entry into the crypt William Burroughs shared with his mother opened and shut around a failed re-enactment of William Tell’s shot through the prop placed upon a loved one’s head. The accidental killing of his wife Joan completed the installation of the addictation machine that spun melancholia as manic dissemination. An early encryptment to which was added the audio portion of abuse deposited an undeliverable message in WB. Wil- liam could never tell, although his corpus bears the in- scription of this impossibility as another form of pos- sibility. James Godley is currently a doctoral candidate in Eng- lish at SUNY Buffalo, where he studies psychoanalysis, Continental philosophy, and nineteenth-century litera- ture and poetry (British and American. His work on the concept of mourning and “the dead” in Freudian and Lacanian approaches to psychoanalytic thought and in Gothic literature has also spawned an essay on zombie porn. Since entering the Academy of Fine Arts Karlsruhe in 2007, Valentin Hennig has studied in the classes of Sil- via Bächli, Claudio Moser, and Corinne Wasmuht. In 2010 he spent a semester at the Dresden Academy of Fine Arts. His work has been shown in group exhibi- tions in Freiburg and Karlsruhe.

  14. Machine musicianship

    Science.gov (United States)

    Rowe, Robert

    2002-05-01

    The training of musicians begins by teaching basic musical concepts, a collection of knowledge commonly known as musicianship. Computer programs designed to implement musical skills (e.g., to make sense of what they hear, perform music expressively, or compose convincing pieces) can similarly benefit from access to a fundamental level of musicianship. Recent research in music cognition, artificial intelligence, and music theory has produced a repertoire of techniques that can make the behavior of computer programs more musical. Many of these were presented in a recently published book/CD-ROM entitled Machine Musicianship. For use in interactive music systems, we are interested in those which are fast enough to run in real time and that need only make reference to the material as it appears in sequence. This talk will review several applications that are able to identify the tonal center of musical material during performance. Beyond this specific task, the design of real-time algorithmic listening through the concurrent operation of several connected analyzers is examined. The presentation includes discussion of a library of C++ objects that can be combined to perform interactive listening and a demonstration of their capability.

  15. Development of submersible axial pump for wastewater

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Jeong Eui [Kangwon Nat' l Univ., Chuncheon (Korea, Republic of)

    2013-02-15

    This study was performed to develop a high efficiency submersible axial pump for concentration wastewater treatment. To do this, we simulated the effect of some parameters such as the axial twist angle of a blade({beta}), the radial twist angle of a blade({alpha}) and the length of a blade ({iota}) on pump efficiency using commercial code, ANSYS CFX and BladeGen. The results showed that the axial twist angle of a blade({beta}) was the most sensible parameter on the pump efficiency. And the pump efficiency had a maximum at {beta}=20.deg, {alpha}=110.deg and {iota}=240mm.

  16. Axial magnetic field injection in magnetized liner inertial fusion

    Science.gov (United States)

    Gourdain, P.-A.; Adams, M. B.; Davies, J. R.; Seyler, C. E.

    2017-10-01

    MagLIF is a fusion concept using a Z-pinch implosion to reach thermonuclear fusion. In current experiments, the implosion is driven by the Z-machine using 19 MA of electrical current with a rise time of 100 ns. MagLIF requires an initial axial magnetic field of 30 T to reduce heat losses to the liner wall during compression and to confine alpha particles during fusion burn. This field is generated well before the current ramp starts and needs to penetrate the transmission lines of the pulsed-power generator, as well as the liner itself. Consequently, the axial field rise time must exceed hundreds of microseconds. Any coil capable of being submitted to such a field for that length of time is inevitably bulky. The space required to fit the coil near the liner, increases the inductance of the load. In turn, the total current delivered to the load decreases since the voltage is limited by driver design. Yet, the large amount of current provided by the Z-machine can be used to produce the required 30 T field by tilting the return current posts surrounding the liner, eliminating the need for a separate coil. However, the problem now is the field penetration time, across the liner wall. This paper discusses why skin effect arguments do not hold in the presence of resistivity gradients. Numerical simulations show that fields larger than 30 T can diffuse across the liner wall in less than 60 ns, demonstrating that external coils can be replaced by return current posts with optimal helicity.

  17. Applied Hts Bulks and Wires to Rotating Machines for Marine Propulsion

    Science.gov (United States)

    Miki, M.; Felder, B.; Kimura, Y.; Tsuzuki, K.; Taguchi, R.; Shiliang, Y.; Xu, Y.; Ida, T.; Izumi, M.

    2010-04-01

    High-temperature superconductors allow a compact and efficient way to provide high-torque density to rotating machines with excellent operation. A field pole, providing flux density of more than 1.5 T around the armature, was initially designed for an axial-gap type with the flux parallel to the rotor axis. Melt-growth Gd-123 bulks as well as Bi-2223 wire windings have been successfully assembled on the rotor disk. No iron core was used, though being an auxiliary flux control found in most HTS motors. Both bulk and wire types have realized a practical motor operation within a limited output range. For bulks, a 15 kW, 720 rpm, synchronous motor was designed and tested in the group of TUMSAT, Kitano Seiki and University of Fukui. A bulk field pole was cooled down by liquid nitrogen and was magnetized in the motor. To enhance the output power to more than 30 kW, we developed a thermosyphon system using condensed neon. Another field pole with HTS wire for large-scale marine propulsion is also discussed on a 100 kW, 230 rpm tested machine. A closed-cycle condensed neon associated with thermal insulation is also reported.

  18. Rotating electric machine with fluid supported parts

    Science.gov (United States)

    Smith, Jr., Joseph L.; Kirtley, Jr., James L.

    1981-01-01

    A rotating electric machine in which the armature winding thereof and other parts are supported by a liquid to withstand the mechanical stresses applied during transient overloads and the like. In particular, a narrow gap is provided between the armature winding and the stator which supports it and this gap is filled with an externally pressurized viscous liquid. The liquid is externally pressurized sufficiently to balance the static loads on the armature winding. Transient mechanical loads which deform the armature winding alter the gap dimensions and thereby additionally pressurize the viscous liquid to oppose the armature winding deformation and more nearly uniformly to distribute the resulting mechanical stresses.

  19. A Functional Correspondence Between Evaluators and Abstract Machines

    DEFF Research Database (Denmark)

    Ager, Mads Sig; Biernacki, Dariusz; Danvy, Olivier

    2003-01-01

    We bridge the gap between functional evaluators and abstract machines for the λ-calculus, using closure conversion, transformation into continuation-passing style, and defunctionalization.We illustrate this approach by deriving Krivine's abstract machine from an ordinary call-by-name evaluator an...

  20. Axial transport of fission gas in LWR fuel rods

    International Nuclear Information System (INIS)

    Kinoshita, M.

    1983-01-01

    With regard to fission gas transportation inside the fuel rod, the following three mechanisms are important: (1) a localized and time dependent fission gas release from UO 2 fuel to pellet/clad gap, (2) the consequent gas pressure difference between the gap and the plenum, and (3) the inter-diffusion of initially filled Helium and released fission gas such as Xenon. Among these three mechanisms, the 2nd mechanism would result in the one dimensional flow through P/C gap in the axial direction, while the 3rd would average the local fission gas concentration difference. In this paper, an attempt was made to develop a computerized model, LINUS (LINear flow and diffusion under Un-Steady condition) describing the above two mechanisms, items (2) and (3). The item (1) is treated as an input. The code was applied to analyse short length experimental fuel rods and long length commercial fuel rods. The calculated time evolution of Xe concentration along the fuel column shows that the dilution rate of Xe in commercial fuel rods is much slower than that in short experimental fuel rods. Some other sensitivity studies, such as the effect of pre-pressurization, are also presented. (author)

  1. VERY SLOW SPEED AXIAL MOTION RELUCTANCE MOTOR

    African Journals Online (AJOL)

    Dr Obe

    1984-09-01

    Sep 1, 1984 ... VERY SLOW SPEED AXIAL MOTION RELUCTANCE MOTOR by. L. A. Agu ... order as that of the screw-thread motor can be obtained. LIST OF .... The n stator have equal non- magnetic spacers .... induction motor. An.

  2. Precision axial translator with high stability.

    Science.gov (United States)

    Bösch, M A

    1979-08-01

    We describe a new type of translator which is inherently stable against torsion and twisting. This concentric translator is also ideally suited for precise axial motion with clearance of the center line.

  3. Axial force measurement for esophageal function testing

    DEFF Research Database (Denmark)

    Gravesen, Flemming Holbæk; Funch-Jensen, Peter; Gregersen, Hans

    2009-01-01

    force (force in radial direction) whereas the bolus moves along the length of esophagus in a distal direction. Force measurements in the longitudinal (axial) direction provide a more direct measure of esophageal transport function. The technique used to record axial force has developed from external...... force transducers over in-vivo strain gauges of various sizes to electrical impedance based measurements. The amplitude and duration of the axial force has been shown to be as reliable as manometry. Normal, as well as abnormal, manometric recordings occur with normal bolus transit, which have been...... documented using imaging modalities such as radiography and scintigraphy. This inconsistency using manometry has also been documented by axial force recordings. This underlines the lack of information when diagnostics are based on manometry alone. Increasing the volume of a bag mounted on a probe...

  4. Theorem on axially symmetric gravitational vacuum configurations

    Energy Technology Data Exchange (ETDEWEB)

    Papadopoulos, A; Le Denmat, G [Paris-6 Univ., 75 (France). Inst. Henri Poincare

    1977-01-24

    A theorem is proved which asserts the non-existence of axially symmetric gravitational vacuum configurations with non-stationary rotation only. The eventual consequences in black-hole physics are suggested.

  5. Buoyant Helical Twin-Axial Wire Antenna

    Science.gov (United States)

    2016-11-15

    February 2017 The below identified patent application is available for licensing. Requests for information should be addressed to...300169 1 of 9 BUOYANT HELICAL TWIN-AXIAL WIRE ANTENNA CROSS REFERENCE TO OTHER PATENT APPLICATIONS [0001] This application is a divisional...application and claims the benefit of the filing date of United States Patent Application No. 14/280,889; filed on May 19, 2014; and entitled “Twin-Axial

  6. Nonperturbative Aspects of Axial Vector Vertex

    Institute of Scientific and Technical Information of China (English)

    ZONG Hong-Shi; CHEN Xiang-Song; WANG Fan; CHANG Chao-Hsi; ZHAO En-Guang

    2002-01-01

    It is shown how the axial vector current of current quarks is related to that of constituent quarks within the framework of the global color symmetry model.Gluon dressing of the axial vector vertex and the quark self-energy functions are described by the inhomogeneous Bethe-Salpeter equation in the ladder approximation and the Schwinger Dyson equation in the rainbow approximation,respectively.

  7. High temperature co-axial winding transformers

    Science.gov (United States)

    Divan, Deepakraj M.; Novotny, Donald W.

    1993-01-01

    The analysis and design of co-axial winding transformers is presented. The design equations are derived and the different design approaches are discussed. One of the most important features of co-axial winding transformers is the fact that the leakage inductance is well controlled and can be made low. This is not the case in conventional winding transformers. In addition, the power density of co-axial winding transformers is higher than conventional ones. Hence, using co-axial winding transformers in a certain converter topology improves the power density of the converter. The design methodology used in meeting the proposed specifications of the co-axial winding transformer specifications are presented and discussed. The final transformer design was constructed in the lab. Co-axial winding transformers proved to be a good choice for high power density and high frequency applications. They have a more predictable performance compared with conventional transformers. In addition, the leakage inductance of the transformer can be controlled easily to suit a specific application. For space applications, one major concern is the extraction of heat from power apparatus to prevent excessive heating and hence damaging of these units. Because of the vacuum environment, the only way to extract heat is by using a cold plate. One advantage of co-axial winding transformers is that the surface area available to extract heat from is very large compared to conventional transformers. This stems from the unique structure of the co-axial transformer where the whole core surface area is exposed and can be utilized for cooling effectively. This is a crucial issue here since most of the losses are core losses.

  8. Dechanneling function for relativistic axially channeled electrons

    International Nuclear Information System (INIS)

    Muralev, V.A.; Telegin, V.I.

    1981-01-01

    Behaviour of the x(t) dechanneling function depending on the depth is theoretically studied. Theoretical consideration of x(t) for axial channeled relativistic electrons in anisotropic medium results in two-dimensional kinetic equation with mixed derivatives of the parabolic type. The kinetic equation in the approximation of the continuous Lindchard model for relativistic axial channeled electrons is numerically solved. The depth dependence of the x(t) dechanneling function is obtained [ru

  9. Axial forces in centrifugal compressor couplings

    Science.gov (United States)

    Ivanov, A. N.; Ivanov, N. M.; Yun, V. K.

    2017-08-01

    The article presents the results of the theoretical and experimental investigation of axial forces arising in the toothed and plate couplings of centrifugal compressor shaft lines. Additional loads on the thrust bearing are considered that can develop in the toothed couplings as a result of coupled rotors misalignment. Design relationships to evaluate the level of axial forces and recommendations for their reduction in the operating conditions are given.

  10. Singlet axial constant from QCD sum rules

    International Nuclear Information System (INIS)

    Belitskij, A.V.; Teryaev, O.V.

    1995-01-01

    We analyze the singlet axial form factor of the proton for small momentum transferred in the framework of QCD sum rules using the interpolating nucleon current which explicitly accounts for the gluonic degrees of freedom. As the result we come to the quantitative prediction of the singlet axial constant. It is shown that the bilocal power corrections play the most important role in the analysis. 21 refs., 3 figs

  11. Computer axial tomography in geosciences

    International Nuclear Information System (INIS)

    Duliu, Octavian G.

    2002-01-01

    Computer Axial Tomography (CAT) is one of the most adequate non-invasive techniques for the investigation of the internal structure of a large category of objects. Initially designed for medical investigations, this technique, based on the attenuation of X- or gamma-ray (and in some cases neutrons), generates digital images which map the numerical values of the linear attenuation coefficient of a section or of the entire volume of the investigated sample. Shortly after its application in medicine, CAT has been successfully used in archaeology, life sciences, and geosciences as well as for the industrial materials non-destructive testing. Depending on the energy of the utilized radiation as well as on the effective atomic number of the sample, CAT can provide with a spatial resolution of 0.01 - 0.5 mm, quantitative as well as qualitative information concerning local density, porosity or chemical composition of the sample. At present two types of axial Computer Tomographs (CT) are in use. One category, consisting of medical as well as industrial CT is equipped with X-ray tubes while the other uses isotopic gamma-ray sources. CT provided with intense X-ray sources (equivalent to 12-15 kCi or 450-550 TBq) has the advantage of an extremely short running time (a few seconds and even less) but presents some disadvantages known as beam hardening and absorption edge effects. These effects, intrinsically related to the polychromatic nature of the X-rays generated by classical tubes, need special mathematical or physical corrections. A polychromatic X-ray beam can be made almost monochromatic by means of crystal diffraction or by using adequate multicomponent filters, but these devices are costly and considerably diminish the output of X-ray generators. In the case of CT of the second type, monochromatic gamma-rays generated by radioisotopic sources, such as 169 Yb (50.4 keV), 241 Am (59 keV), 192 Ir (310.5 and 469.1 keV ) or 137 Cs (662.7 keV), are used in combination with

  12. Hyperquenched hyaloclastites from Axial Seamount

    Science.gov (United States)

    Zezin, D.; Helo, C.; Richard, D.; Clague, D. A.; Dingwell, D. B.; Stix, J.

    2009-12-01

    We determined apparent cooling rates for basaltic hyaloclastites from Axial caldera, Juan de Fuca Ridge. Samples originate from different stratigraphic layers within the unconsolidated volcaniclastic sequences, on flanks of the volcanic edifice. Water depth is ~1400 m below sea level. The hyaloclastite glass fragments comprise two principal morphologies: (1) angular fragments, and (2) thin glassy melt films interpreted as bubble walls, called deep-sea limu o Pele. A natural cooling rate was estimated for each sample of ~50 carefully selected glass shards. The heat capacity was first measured with a differential scanning calorimeter in two heating scans with heating rates of 20 K/min, and a matching cooling rate between those scans. The fictive temperatures Tf were then determined from both heating cycles, and the natural cooling rate derived by the non-Arrhenian relationship between Tf and cooling rate. All samples display hyperquenched states, manifested in a strong exothermic energy release during the initial heating cycle before reaching the glass transition. Cooling rates range from 10 6.73 K/s to 10 3.94 K/s for the limu, and 10 4.92 K/s to 10 2.34 K/s for the angular fragments. Almost all samples of limu shards show elevated cooling rates compared to their angular counterparts of comparable grain mass. In addition, the exothermic part of the enthalpy curves reveal two superimposed relaxation domains, the main broad exothermal peak, ranging from ~350 K to the onset of the glass transition, and a small subordinate peak/shoulder occurring between 550 K and 700 K. The magnitude of the latter varies from clearly identifiable to nearly absent, and tends to be more pronounced in curves obtained from angular fragments. The main exothermal peak is related to the frozen-in structure of the glass and consequently to its thermal history when passing through the glass transition. The subordinate peak may represent strain rate-induced and tensile stress accumulation

  13. Machine technology: a survey

    International Nuclear Information System (INIS)

    Barbier, M.M.

    1981-01-01

    An attempt was made to find existing machines that have been upgraded and that could be used for large-scale decontamination operations outdoors. Such machines are in the building industry, the mining industry, and the road construction industry. The road construction industry has yielded the machines in this presentation. A review is given of operations that can be done with the machines available

  14. Machine Shop Lathes.

    Science.gov (United States)

    Dunn, James

    This guide, the second in a series of five machine shop curriculum manuals, was designed for use in machine shop courses in Oklahoma. The purpose of the manual is to equip students with basic knowledge and skills that will enable them to enter the machine trade at the machine-operator level. The curriculum is designed so that it can be used in…

  15. Superconducting rotating machines

    International Nuclear Information System (INIS)

    Smith, J.L. Jr.; Kirtley, J.L. Jr.; Thullen, P.

    1975-01-01

    The opportunities and limitations of the applications of superconductors in rotating electric machines are given. The relevant properties of superconductors and the fundamental requirements for rotating electric machines are discussed. The current state-of-the-art of superconducting machines is reviewed. Key problems, future developments and the long range potential of superconducting machines are assessed

  16. Design of Single Stage Axial Turbine with Constant Nozzle Angle Blading for Small Turbojet

    Science.gov (United States)

    Putra Adnan, F.; Hartono, Firman

    2018-04-01

    In this paper, an aerodynamic design of a single stage gas generator axial turbine for small turbojet engine is explained. As per design requirement, the turbine should be able to deliver power output of 155 kW at 0.8139 kg/s gas mass flow, inlet total temperature of 1200 K and inlet total pressure of 335330 Pa. The design phase consist of several steps, i.e.: determination of velocity triangles in 2D plane, 2D blading design and 3D flow analysis at design point using Computational Fluid Dynamics method. In the determination of velocity triangles, two conditions are applied: zero inlet swirl (i.e. the gas flow enter the turbine at axial direction) and constant nozzle angle design (i.e. the inlet and outlet angle of the nozzle blade are constant from root to tip). The 2D approach in cascade plane is used to specify airfoil type at root, mean and tip of the blade based on inlet and outlet flow conditions. The 3D approach is done by simulating the turbine in full configuration to evaluate the overall performance of the turbine. The observed parameters including axial gap, stagger angle, and tip clearance affect its output power. Based on analysis results, axial gap and stagger angle are positively correlated with output power up to a certain point at which the power decreases. Tip clearance, however, gives inversely correlation with output power.

  17. Transition Towards Energy Efficient Machine Tools

    CERN Document Server

    Zein, André

    2012-01-01

    Energy efficiency represents a cost-effective and immediate strategy of a sustainable development. Due to substantial environmental and economic implications, a strong emphasis is put on the electrical energy requirements of machine tools for metalworking processes. The improvement of energy efficiency is however confronted with diverse barriers, which sustain an energy efficiency gap of unexploited potential. The deficiencies lie in the lack of information about the actual energy requirements of machine tools, a minimum energy reference to quantify improvement potential and the possible actions to improve the energy demand. Therefore, a comprehensive concept for energy performance management of machine tools is developed which guides the transition towards energy efficient machine tools. It is structured in four innovative concept modules, which are embedded into step-by-step workflow models. The capability of the performance management concept is demonstrated in an automotive manufacturing environment. The ...

  18. Torque ripple reduction in electric machines

    Science.gov (United States)

    Reddy, Patel Bhageerath; Huh, Kum-Kang; El-Refaie, Ayman Mohamed Fawzi; Galioto, Steven Joseph

    2017-08-22

    An electric machine, such as an Internal Permanent magnet or Synchronous Reluctance machine, having X phases, that includes a stator assembly, having M slots, with a stator core and stator teeth, that is further configured with stator windings to generate a stator magnetic field when excited with alternating currents and extends along a longitudinal axis with an inner surface that defines a cavity; and a rotor assembly, having N poles, disposed within the cavity which is configured to rotate about the longitudinal axis, wherein the rotor assembly includes a shaft, a rotor core located circumferentially around the shaft. The machine is configured such that a value k=M/(X*N) wherein k is a non-integer greater than about 1.3. The electric machine may alternatively, or additionally, include a non-uniformed gap between the exterior surface of the rotor spokes and the interior stator surface of the stator.

  19. Vector and axial constants of the baryon decuplet

    International Nuclear Information System (INIS)

    Belyaev, V.M.; Blok, B.Y.; Kogan, Y.I.

    1985-01-01

    On the basis of the QCD sum rules for the polarization operator in external axial and vector fields we determine the vector and axial transition constants in the 3/2 + baryon decuplet. We show that the renormalization of the axial constant is due to the interaction of the external axial field with the quark condensate

  20. Δ(1232) Axial Charge and Form Factors from Lattice QCD

    International Nuclear Information System (INIS)

    Alexandrou, Constantia; Gregory, Eric B.; Korzec, Tomasz; Koutsou, Giannis; Negele, John W.; Sato, Toru; Tsapalis, Antonios

    2011-01-01

    We present the first calculation on the Δ axial vector and pseudoscalar form factors using lattice QCD. Two Goldberger-Treiman relations are derived and examined. A combined chiral fit is performed to the nucleon axial charge, N to Δ axial transition coupling constant and Δ axial charge.

  1. Using axial magnetized permanent rings to build axial gradient magnetic field

    International Nuclear Information System (INIS)

    Peng Quanling

    2003-01-01

    Axial field produced by an axially magnetized permanent ring was studied. For two permanent magnet rings, if they are magnetized in the same direction, a nearly uniform axial field can be produced; if they are magnetized in opposite direction, an axial gradient field can be produced in the region between the two permanent rings, with the field strength changing from -B 0 to B 0 . A high gradient axial magnetic field has been built by using two axially magnetized permanent rings, the measured field results agree with the PANDIRA calculation very well. It is desirable that the field gradient can be varied to match various requirements. A method to produce the variable gradient field is presented. Axial gradient field can also be used as a beam focusing facility for linear accelerator if axial periodic field can be produced. Its magnetic field is similar to that of a solenoid, in which, large stray field will leak to the outside environment. A method for shielding the outside stray field is discussed

  2. Optimization of residual heat removal pump axial thrust and axial bearing

    International Nuclear Information System (INIS)

    Schubert, F.

    1996-01-01

    The residual heat removal (RHR) pumps of German 1300 megawatt pressurized-water reactor (PWR) power plants are of the single stage end suction type with volute casing or with diffuser and forged circular casing. Due to the service conditions the pumps have to cover the full capacity range as well as a big variation in suction static pressure. This results in a big difference in the axial thrust that has to be borne by the axial bearing. Because these pumps are designed to operate without auxiliary systems (things that do not exist can not fail), they are equipped with antifriction bearings and sump oil lubrication. To minimize the heat production within the bearing casing, a number of PWR plants have pumps with combined axial/radial bearings of the ball type. Due to the fact that the maximum axial thrust caused by static pressure and hydrodynamic forces on the impeller is too big to be borne by that type of axial bearing, the impellers were designed to produce a hydrodynamic axial force that counteracts the static axial force. Thus, the resulting axial thrust may change direction when the static pressure varies

  3. Optimization of residual heat removal pump axial thrust and axial bearing

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, F.

    1996-12-01

    The residual heat removal (RHR) pumps of German 1300 megawatt pressurized-water reactor (PWR) power plants are of the single stage end suction type with volute casing or with diffuser and forged circular casing. Due to the service conditions the pumps have to cover the full capacity range as well as a big variation in suction static pressure. This results in a big difference in the axial thrust that has to be borne by the axial bearing. Because these pumps are designed to operate without auxiliary systems (things that do not exist can not fail), they are equipped with antifriction bearings and sump oil lubrication. To minimize the heat production within the bearing casing, a number of PWR plants have pumps with combined axial/radial bearings of the ball type. Due to the fact that the maximum axial thrust caused by static pressure and hydrodynamic forces on the impeller is too big to be borne by that type of axial bearing, the impellers were designed to produce a hydrodynamic axial force that counteracts the static axial force. Thus, the resulting axial thrust may change direction when the static pressure varies.

  4. The prototype GAPS (pGAPS) experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mognet, S.A.I., E-mail: mognet@astro.ucla.edu [University of California, Los Angeles, CA 90095 (United States); Aramaki, T. [Columbia University, New York, NY 10027 (United States); Bando, N. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Boggs, S.E.; Doetinchem, P. von [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Fuke, H. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Gahbauer, F.H.; Hailey, C.J.; Koglin, J.E.; Madden, N. [Columbia University, New York, NY 10027 (United States); Mori, K.; Okazaki, S. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Ong, R.A. [University of California, Los Angeles, CA 90095 (United States); Perez, K.M.; Tajiri, G. [Columbia University, New York, NY 10027 (United States); Yoshida, T. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (ISAS/JAXA), Sagamihara, Kanagawa 252-5210 (Japan); Zweerink, J. [University of California, Los Angeles, CA 90095 (United States)

    2014-01-21

    The General Antiparticle Spectrometer (GAPS) experiment is a novel approach for the detection of cosmic ray antiparticles. A prototype GAPS (pGAPS) experiment was successfully flown on a high-altitude balloon in June of 2012. The goals of the pGAPS experiment were: to test the operation of lithium drifted silicon (Si(Li)) detectors at balloon altitudes, to validate the thermal model and cooling concept needed for engineering of a full-size GAPS instrument, and to characterize cosmic ray and X-ray backgrounds. The instrument was launched from the Japan Aerospace Exploration Agency's (JAXA) Taiki Aerospace Research Field in Hokkaido, Japan. The flight lasted a total of 6 h, with over 3 h at float altitude (∼33km). Over one million cosmic ray triggers were recorded and all flight goals were met or exceeded.

  5. The prototype GAPS (pGAPS) experiment

    International Nuclear Information System (INIS)

    Mognet, S.A.I.; Aramaki, T.; Bando, N.; Boggs, S.E.; Doetinchem, P. von; Fuke, H.; Gahbauer, F.H.; Hailey, C.J.; Koglin, J.E.; Madden, N.; Mori, K.; Okazaki, S.; Ong, R.A.; Perez, K.M.; Tajiri, G.; Yoshida, T.; Zweerink, J.

    2014-01-01

    The General Antiparticle Spectrometer (GAPS) experiment is a novel approach for the detection of cosmic ray antiparticles. A prototype GAPS (pGAPS) experiment was successfully flown on a high-altitude balloon in June of 2012. The goals of the pGAPS experiment were: to test the operation of lithium drifted silicon (Si(Li)) detectors at balloon altitudes, to validate the thermal model and cooling concept needed for engineering of a full-size GAPS instrument, and to characterize cosmic ray and X-ray backgrounds. The instrument was launched from the Japan Aerospace Exploration Agency's (JAXA) Taiki Aerospace Research Field in Hokkaido, Japan. The flight lasted a total of 6 h, with over 3 h at float altitude (∼33km). Over one million cosmic ray triggers were recorded and all flight goals were met or exceeded

  6. Investigation of flow in axial turbine stage without shroud-seal

    Directory of Open Access Journals (Sweden)

    Straka Petr

    2015-01-01

    Full Text Available This article deals with investigation of the influence of the radial gaps on the efficiency of the axial turbine stage. The investigation was carried out for the axial stage of the low-power turbine with the drum-type rotor without the shroud. In this configuration the flow through the radial gap under the hub-end of the stator blades and above the tip-end of the rotor blades leads to generation of the strong secondary flows, which decrease the efficiency of the stage. This problem was studied by experiment as well as by numerical modelling. The experiment was performed on the test rig equipped with the water brake dynamometer, torque meter and rotatable stator together with the linear probe manipulator. Numerical modelling was carried out for both the steady flow using the ”mixing plane” interface and the unsteady flow using the ”sliding mesh” interface between the stator and rotor wheels. The influence of the radial gap was studied in two configuration a positive and b negative overlapping of the tip-ends of the rotor blades. The efficiency of the axial stage in dependence on the expansion ratio, velocity ratio and the configuration as well as the details of the flow fields are presented in this paper.

  7. A Comparison of the Effects of K-Anonymity on Machine Learning Algorithms

    OpenAIRE

    Hayden Wimmer; Loreen Powell

    2014-01-01

    While research has been conducted in machine learning algorithms and in privacy preserving in data mining (PPDM), a gap in the literature exists which combines the aforementioned areas to determine how PPDM affects common machine learning algorithms. The aim of this research is to narrow this literature gap by investigating how a common PPDM algorithm, K-Anonymity, affects common machine learning and data mining algorithms, namely neural networks, logistic regression, decision trees, and Baye...

  8. Optimización de Estatores para Motores Superconductores de Flujo Axial Optimización de Estatores para Motores Superconductores de Flujo Axial

    Directory of Open Access Journals (Sweden)

    Oscar Gerardo Ibarra-Manzano

    2012-02-01

    Full Text Available The development of superconducting electrical machines has been designed primarily to design and build engines with the superconducting magnetic field in radial configuration, as traditional engines, so the design and construction of rotating electrical machines in axial flow configuration has become an alternative for the design and construction of such engines. In this paper we present preliminary calculations for the optimization of the stator of a superconducting motor in axial flow confi guration, based on the equations of general power of the rotary axial flow configuration. It performs the construction, optimization and evaluation of models of stators in geometries of 4, 6 and 8 poles with high-temperature superconducting tapes of Bismuth. The results show the feasibility of the design implemented, which is verified by a significant decrease in the current of superconducting motor operation.El desarrollo de máquinas eléctricas superconductoras ha estado encaminado principalmentea diseñar y construir motores superconductores con el campo magnético en configuración radial, como los motores tradicionales, por lo que el diseño y construcción demáquinas eléctricas rotativas en configuración de flujo axial ha venido a ser una alternativa para el diseño y construcción de este tipo de motores. En el presente trabajo se presentan los cálculos preliminares para la optimización del estator de un motor superconductor en configuración de flujo axial, basados en las ecuaciones generales de potencia de las máquinas eléctricas rotativas en configuración flujo axial ha venido a ser una alternativa para el diseño y construcción, optimización y evaluación de modelos de estatores en geometrías de 4, 6 y 8 polos, con cintas superconductoras de alta temperatura de Bismuto. Los resultados obtenidos muestran la viabilidaddel diseño implementado, lo cual se comprueba por medio de una disminución significativa de la corriente de operaci

  9. Improving the lattice axial vector current

    International Nuclear Information System (INIS)

    Horsley, R.; Perlt, H.; Schiller, A.; Zanotti, J.M.

    2015-11-01

    For Wilson and clover fermions traditional formulations of the axial vector current do not respect the continuum Ward identity which relates the divergence of that current to the pseudoscalar density. Here we propose to use a point-split or one-link axial vector current whose divergence exactly satisfies a lattice Ward identity, involving the pseudoscalar density and a number of irrelevant operators. We check in one-loop lattice perturbation theory with SLiNC fermion and gauge plaquette action that this is indeed the case including order O(a) effects. Including these operators the axial Ward identity remains renormalisation invariant. First preliminary results of a nonperturbative check of the Ward identity are also presented.

  10. Diagnostic value of axial CT scan

    International Nuclear Information System (INIS)

    Kiuchi, Sousuke

    1983-01-01

    Axial CT scan was used to investigate the radiological details of the temporal bone of 33 patients with chronic otitis media, secondary cholesteatoma, sensorineural hearing loss, Meniere disease, vertigo, facial spasm, and neoplasma. The axial scans showed anatomic details of the temporal bone, and at the same time clearly demonstrated the extent of the soft-tissue masses in the middle ears, as well as the destructions of the ossicles. Bone changes of the anterior walls of the epitympanum and external auditory meatus were more clearly demonstrated than by coronary CT scan. However, the axial scan had the disadvantages in demonstrating the stapes, crista transversa, and the mastoid portion of the facial canal. (author)

  11. Whistler mode startup in the Michigan Mirror Machine

    International Nuclear Information System (INIS)

    Booske, J.; Getty, W.D.; Gilgenbach, R.M.; Goodman, T.; Whaley, D.; Olivieri, R.; Pitcher, E.; Simonetti, L.

    1985-01-01

    Results of investigations of whistler mode ECRH plasma startup in the Michigan Mirror Machine are presented. Electron-velocity-distribution and plasma-spatial-distribution time evolution are characterized by measurements from axially and radially moveable Langmuir probes, an endloss current detector, an electron cyclotron emission radiometer, a foil-filtered X-ray detector, and a diamagnetic loop at the mirror midplane. Measurements of the buildup of both electron density and perpendicular pressure (nkT/sub perpendicular/) are compared to predictions from various numerical models. Both modeling and data suggest the creation of a highly anisotropic electron velocity distribution function with a ''sloshing electron'' axial density profile

  12. Stator for a rotating electrical machine having multiple control windings

    Science.gov (United States)

    Shah, Manoj R.; Lewandowski, Chad R.

    2001-07-17

    A rotating electric machine is provided which includes multiple independent control windings for compensating for rotor imbalances and for levitating/centering the rotor. The multiple independent control windings are placed at different axial locations along the rotor to oppose forces created by imbalances at different axial locations along the rotor. The multiple control windings can also be used to levitate/center the rotor with a relatively small magnetic field per unit area since the rotor and/or the main power winding provides the bias field.

  13. Machine tool structures

    CERN Document Server

    Koenigsberger, F

    1970-01-01

    Machine Tool Structures, Volume 1 deals with fundamental theories and calculation methods for machine tool structures. Experimental investigations into stiffness are discussed, along with the application of the results to the design of machine tool structures. Topics covered range from static and dynamic stiffness to chatter in metal cutting, stability in machine tools, and deformations of machine tool structures. This volume is divided into three sections and opens with a discussion on stiffness specifications and the effect of stiffness on the behavior of the machine under forced vibration c

  14. Axial Vircator for Electronic Warfare Applications

    Directory of Open Access Journals (Sweden)

    L. Drazan

    2009-12-01

    Full Text Available This paper deals with a high power microwave generator with virtual cathode – vircator in axial release for electronic warfare applications. The classification of directed energy weapons microwave (DEWM is introduced together with basic block diagrams of a particular class of DEWM. In the paper, methods for designing vircator pulsed power supply, axial vircator structure, measurement methods and experimental results are presented. The vircator in electromagnetic ammunition is powered by magneto-cumulative generator and in weapons for defense of objects (WDO, it is powered by Marx generator. The possible applications of a vircator in the DEWM area are discussed.

  15. Axial loaded MRI of the lumbar spine

    Energy Technology Data Exchange (ETDEWEB)

    Saifuddin, A. E-mail: asaifuddin@aol.com; Blease, S.; MacSweeney, E

    2003-09-01

    Magnetic resonance imaging is established as the technique of choice for assessment of degenerative disorders of the lumbar spine. However, it is routinely performed with the patient supine and the hips and knees flexed. The absence of axial loading and lumbar extension results in a maximization of spinal canal dimensions, which may in some cases, result in failure to demonstrate nerve root compression. Attempts have been made to image the lumbar spine in a more physiological state, either by imaging with flexion-extension, in the erect position or by using axial loading. This article reviews the literature relating to the above techniques.

  16. Axial nucleon form factors from lattice QCD

    International Nuclear Information System (INIS)

    Alexandrou, C.; Brinet, M.; Carbonell, J.; Harraud, P. A.; Papinutto, M.; Constantinou, M.; Guichon, P.; Jansen, K.; Korzec, T.

    2011-01-01

    We present results on the nucleon axial form factors within lattice QCD using two flavors of degenerate twisted mass fermions. Volume effects are examined using simulations at two volumes of spatial length L=2.1 fm and L=2.8 fm. Cut-off effects are investigated using three different values of the lattice spacings, namely a=0.089 fm, a=0.070 fm and a=0.056 fm. The nucleon axial charge is obtained in the continuum limit and chirally extrapolated to the physical pion mass enabling comparison with experiment.

  17. The Axially Symmetric One-Monopole

    International Nuclear Information System (INIS)

    Wong, K.-M.; Teh, Rosy

    2009-01-01

    We present new classical generalized one-monopole solution of the SU(2) Yang-Mills-Higgs theory with the Higgs field in the adjoint representation. We show that this solution with θ-winding number m = 1 and φ-winding number n = 1 is an axially symmetric generalization of the 't Hooft-Polyakov one-monopole. We construct this axially symmetric one-monopole solution by generalizing the large distance asymptotic solutions of the 't Hooft-Polyakov one-monopole to the Jacobi elliptic functions and solving the second order equations of motion numerically when the Higgs potential is vanishing. This solution is a non-BPS solution.

  18. Axial injection in Orsay superconducting cyclotron

    International Nuclear Information System (INIS)

    Depauw, J.; Kugler, M.F.; Legoff, A.; Potier, J.C.; Richomme, A.; Skowron, R.; Mandrillon, P.; Schapira, J.P.

    1983-01-01

    The compact superconducting cyclotron currently planned at IPN at Orsay is designed for light ion acceleration together with heavy ion acceleration. From the beginning, for this reason, a central geometry able to receive an inflector (to 90deg C) allowing the axial injection of low energy ion beams given by an outer source. The present study is aimed at showing the technical feasibility of theoretical results obtained on axial injection. First experimental study has been made of spatial repartition in three dimensions of electric potential developed by a central geometry of 3 electrodes. Then, the electric study of an electrostatic mirror has been made [fr

  19. «FLARES» IN AXIAL SPONDYLOARTHRITIS

    Directory of Open Access Journals (Sweden)

    Sh. F. Erdes

    2016-01-01

    Full Text Available The clear definition of the concept of «flare in axial spondyloarthritis» is of paramount importance for clinical trials and routine practice in particular. It will be able to unify the characteristics of outcomes over a particular period of time on the one hand and to standardize therapeutic approaches on the other. On 4 February 2016, the journal Annals of Rheumatic Diseases published the on-line paper «Preliminary definitions of 'flare' in axial spondyloarthritis, based on pain, BASDAI and ASDAS-CRP: an ASAS initiative» by L. Gossec et al., which was devoted to this topic.

  20. Quantum machine learning what quantum computing means to data mining

    CERN Document Server

    Wittek, Peter

    2014-01-01

    Quantum Machine Learning bridges the gap between abstract developments in quantum computing and the applied research on machine learning. Paring down the complexity of the disciplines involved, it focuses on providing a synthesis that explains the most important machine learning algorithms in a quantum framework. Theoretical advances in quantum computing are hard to follow for computer scientists, and sometimes even for researchers involved in the field. The lack of a step-by-step guide hampers the broader understanding of this emergent interdisciplinary body of research. Quantum Machine L

  1. A tape-controlled remote automatic diameter measurement machine

    International Nuclear Information System (INIS)

    Jennison, W.; Salmon, A.M.

    1978-01-01

    The machine is designed for the automatic measurement of fuel pins after irradiation in the fast reactors and is a modified version of a machine which has been in use for several years. These modifications consist of mechanical improvements and solid state control circuitry but the design criteria are unchanged. Irradiated fuel pins with diameters up to 0.875 in. are measured at fixed axial positions and angular intervals. Axial stepping of either 1 cm or 1 in. with a standard deviation of 5 x 10 -4 in. and angular rotation by multiples of 18 0 with a non-cumulative error of 1 0 can be selected. Data on axial position to 0.1 in. or 0.1 cm and fuel element diameter to 5 x 10 -5 in. are both punched and printed out for computer evaluation. The standard deviation of a single measurement on cylindrical specimens with an eccentricity of up to at least 0.1 in. should be no worse than 1 x 10 -4 in. No operator attention is required after the pin is positioned in the machine and 40 sets of 10 diameter readings at 36 0 intervals can be performed in an hour. Switches can be set between 1 and 99 to terminate an examination when power is switched off with the machine in its rest position. (author)

  2. MITS machine operations

    International Nuclear Information System (INIS)

    Flinchem, J.

    1980-01-01

    This document contains procedures which apply to operations performed on individual P-1c machines in the Machine Interface Test System (MITS) at AiResearch Manufacturing Company's Torrance, California Facility

  3. Brain versus Machine Control.

    Directory of Open Access Journals (Sweden)

    Jose M Carmena

    2004-12-01

    Full Text Available Dr. Octopus, the villain of the movie "Spiderman 2", is a fusion of man and machine. Neuroscientist Jose Carmena examines the facts behind this fictional account of a brain- machine interface

  4. Applied machining technology

    CERN Document Server

    Tschätsch, Heinz

    2010-01-01

    Machining and cutting technologies are still crucial for many manufacturing processes. This reference presents all important machining processes in a comprehensive and coherent way. It includes many examples of concrete calculations, problems and solutions.

  5. Machining with abrasives

    CERN Document Server

    Jackson, Mark J

    2011-01-01

    Abrasive machining is key to obtaining the desired geometry and surface quality in manufacturing. This book discusses the fundamentals and advances in the abrasive machining processes. It provides a complete overview of developing areas in the field.

  6. Machine medical ethics

    CERN Document Server

    Pontier, Matthijs

    2015-01-01

    The essays in this book, written by researchers from both humanities and sciences, describe various theoretical and experimental approaches to adding medical ethics to a machine in medical settings. Medical machines are in close proximity with human beings, and getting closer: with patients who are in vulnerable states of health, who have disabilities of various kinds, with the very young or very old, and with medical professionals. In such contexts, machines are undertaking important medical tasks that require emotional sensitivity, knowledge of medical codes, human dignity, and privacy. As machine technology advances, ethical concerns become more urgent: should medical machines be programmed to follow a code of medical ethics? What theory or theories should constrain medical machine conduct? What design features are required? Should machines share responsibility with humans for the ethical consequences of medical actions? How ought clinical relationships involving machines to be modeled? Is a capacity for e...

  7. A Novel Geometry for Shear Test Using Axial Tensile Setup

    Directory of Open Access Journals (Sweden)

    Sibo Yuan

    2018-05-01

    Full Text Available This paper studies a novel geometry for the in-plane shear test performed with an axial electromechanical testing machine. In order to investigate the influence of the triaxiality rate on the mechanical behavior, different tests will be performed on the studied material: simple tensile tests, large tensile tests and shear tests. For the whole campaign, a common equipment should be employed to minimize the impact of the testing device. As a consequence, for the shear tests, the geometry of the specimen must be carefully designed in order to adapt the force value and make it comparable to the one obtained for the tensile tests. Like most of the existing shear-included tensile test specimens, the axial loading is converted to shear loading at a particular region through the effect of geometry. A symmetric shape is generally preferred, since it can restrict the in-plane rotation of the shear section, keep shear increasing in a more monotonic path and double the force level thanks to the two shear zones. Due to the specific experimental conditions, such as dimensions of the furnace and the clamping system, the position of the extensometer or the restriction of sheet thickness (related to the further studies of size effect at mesoscale and hot temperature, several geometries were brought up and evaluated in an iterative procedure via finite element simulations. Both the numerical and experimental results reveal that the final geometry ensures some advantages. For instance, a relatively low triaxiality in the shear zone, limited in-plane rotation and no necking are observed. Moreover, it also prevents any out-of-plane displacement of the specimen which seems to be highly sensitive to the geometry, and presents a very limited influence of the material and the thickness.

  8. Behind the Pay Gap

    Science.gov (United States)

    Dey, Judy Goldberg; Hill, Catherine

    2007-01-01

    Women have made remarkable gains in education during the past three decades, yet these achievements have resulted in only modest improvements in pay equity. The gender pay gap has become a fixture of the U.S. workplace and is so ubiquitous that many simply view it as normal. "Behind the Pay Gap" examines the gender pay gap for college graduates.…

  9. BPHZL-subtraction scheme and axial gauges

    Energy Technology Data Exchange (ETDEWEB)

    Kreuzer, M.; Rebhan, A.; Schweda, M.; Piguet, O.

    1986-03-27

    The application of the BPHZL subtraction scheme to Yang-Mills theories in axial gauges is presented. In the auxillary mass formulation we show the validity of the convergence theorems for subtracted momentum space integrals, and we give the integral formulae necessary for one-loop calculations. (orig.).

  10. Accessory caudal axial and pelvic ribs

    International Nuclear Information System (INIS)

    Bohutova, J.; Kolar, J.; Vitovec, J.; Vyhnanek, L.

    1980-01-01

    Accessory caudal ribs are reported as an extremely curious anomaly in five patients. Once the fracture of this rib was a source of pains after injury. The different shapes of the ribs are documented in this clinical survey which is the most extensive in the present literature. Anomalous ribs arise due to inappropriate segmentation during the embryonal development of the axial skeleton. (orig.) [de

  11. Aryabha~ and Axial Rotation of Earth

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 4. Aryabhata and Axial Rotation of Earth - Naksatra Dina (the Sidereal Day). Amartya Kumar Dutta. General Article Volume 11 Issue 4 April 2006 pp 56-74. Fulltext. Click here to view fulltext PDF. Permanent link:

  12. Aryabhala and Axial Rotation of Earth

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 3. Aryabhata and Axial Rotation of Earth - Khagola (The Celestial Sphere). Amartya Kumar Dutta. General Article Volume 11 Issue 3 March 2006 pp 51-68. Fulltext. Click here to view fulltext PDF. Permanent link:

  13. Helical axial injection concept for cyclotrons

    Energy Technology Data Exchange (ETDEWEB)

    Hudson, E.D.

    1981-01-01

    A concept for an external beam injection system using a helical beam path centered on the cyclotron axis is described. This system could be used to couple two accelerator stages, with or without intermediate stripping, in cases where conventional axial injection or radial injection are not practical.

  14. Helical axial injection concept for cyclotrons

    International Nuclear Information System (INIS)

    Hudson, E.D.

    1981-01-01

    A concept for an external beam injection system using a helical beam path centered on the cyclotron axis is described. This system could be used to couple two accelerator stages, with or without intermediate stripping, in cases where conventional axial injection or radial injection are not practical

  15. The axial polarizability of nucleons and nuclei

    International Nuclear Information System (INIS)

    Ericson, M.; Figureau, A.

    1981-02-01

    The part of the static nuclear axial polarizability arising from the nucleonic excitations is derived from the low energy expansion of the πN amplitude. It is shown that the contribution of the Δ intermediate state, though dominant, does not saturate the nucleonic response. A similar effect, though more pronounced, is known to occur for the magnetic susceptibility

  16. Optimisation of efficiency of axial fans

    NARCIS (Netherlands)

    Kruyt, Nicolaas P.; Pennings, P.C.; Faasen, R.

    2014-01-01

    A three-stage research project has been executed to develop ducted axial-fans with increased efficiency. In the first stage a design method has been developed in which various conflicting design criteria can be incorporated. Based on this design method, an optimised design has been determined

  17. Axial crystals macroscopic symmetry and tensor properties

    Czech Academy of Sciences Publication Activity Database

    Janovec, Václav

    2017-01-01

    Roč. 90, č. 1 (2017), s. 1-10 ISSN 0141-1594 Institutional support: RVO:68378271 Keywords : axial * polar * pseudopolar * chiral * enantiomorphism * optical activity Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 1.060, year: 2016

  18. Visualization and characterization of individual type III protein secretion machines in live bacteria.

    Science.gov (United States)

    Zhang, Yongdeng; Lara-Tejero, María; Bewersdorf, Jörg; Galán, Jorge E

    2017-06-06

    Type III protein secretion machines have evolved to deliver bacterially encoded effector proteins into eukaryotic cells. Although electron microscopy has provided a detailed view of these machines in isolation or fixed samples, little is known about their organization in live bacteria. Here we report the visualization and characterization of the Salmonella type III secretion machine in live bacteria by 2D and 3D single-molecule switching superresolution microscopy. This approach provided access to transient components of this machine, which previously could not be analyzed. We determined the subcellular distribution of individual machines, the stoichiometry of the different components of this machine in situ, and the spatial distribution of the substrates of this machine before secretion. Furthermore, by visualizing this machine in Salmonella mutants we obtained major insights into the machine's assembly. This study bridges a major resolution gap in the visualization of this nanomachine and may serve as a paradigm for the examination of other bacterially encoded molecular machines.

  19. Monocoil reciprocating permanent magnet electric machine with self-centering force

    Science.gov (United States)

    Bhate, Suresh K. (Inventor); Vitale, Nicholas G. (Inventor)

    1989-01-01

    A linear reciprocating machine has a tubular outer stator housing a coil, a plunger and an inner stator. The plunger has four axially spaced rings of radially magnetized permanent magnets which cooperate two at a time with the stator to complete first or second opposite magnetic paths. The four rings of magnets and the stators are arranged so that the stroke of the plunger is independent of the axial length of the coil.

  20. Dictionary of machine terms

    International Nuclear Information System (INIS)

    1990-06-01

    This book has introduction of dictionary of machine terms, and a compilation committee and introductory remarks. It gives descriptions of the machine terms in alphabetical order from a to Z and also includes abbreviation of machine terms and symbol table, way to read mathematical symbols and abbreviation and terms of drawings.

  1. Mankind, machines and people

    Energy Technology Data Exchange (ETDEWEB)

    Hugli, A

    1984-01-01

    The following questions are addressed: is there a difference between machines and men, between human communication and communication with machines. Will we ever reach the point when the dream of artificial intelligence becomes a reality. Will thinking machines be able to replace the human spirit in all its aspects. Social consequences and philosophical aspects are addressed. 8 references.

  2. A Universal Reactive Machine

    DEFF Research Database (Denmark)

    Andersen, Henrik Reif; Mørk, Simon; Sørensen, Morten U.

    1997-01-01

    Turing showed the existence of a model universal for the set of Turing machines in the sense that given an encoding of any Turing machine asinput the universal Turing machine simulates it. We introduce the concept of universality for reactive systems and construct a CCS processuniversal...

  3. HTS machine laboratory prototype

    DEFF Research Database (Denmark)

    machine. The machine comprises six stationary HTS field windings wound from both YBCO and BiSCOO tape operated at liquid nitrogen temperature and enclosed in a cryostat, and a three phase armature winding spinning at up to 300 rpm. This design has full functionality of HTS synchronous machines. The design...

  4. Your Sewing Machine.

    Science.gov (United States)

    Peacock, Marion E.

    The programed instruction manual is designed to aid the student in learning the parts, uses, and operation of the sewing machine. Drawings of sewing machine parts are presented, and space is provided for the student's written responses. Following an introductory section identifying sewing machine parts, the manual deals with each part and its…

  5. NASA Glenn's Single-Stage Axial Compressor Facility Upgraded

    Science.gov (United States)

    Brokopp, Richard A.

    2004-01-01

    NASA Glenn Research Center's Single-Stage Axial Compressor Facility was upgraded in fiscal year 2003 to expand and improve its research capabilities for testing high-speed fans and compressors. The old 3000-hp drive motor and gearbox were removed and replaced with a refurbished 7000-hp drive motor and gearbox, with a maximum output speed of 21,240 rpm. The higher horsepower rating permits testing of fans and compressors with higher pressure ratio or higher flow. A new inline torquemeter was installed to provide an alternate measurement of fan and compressor efficiency, along with the standard pressure and temperature measurements. A refurbished compressor bearing housing was also installed with bidirectional rotation capability, so that a variety of existing hardware could be tested. Four new lubrication modules with backup capability were installed for the motor, gearbox, torquemeter, and compressor bearing housing, so that in case the primary pump fails, the backup will prevent damage to the rotating hardware. The combustion air supply line for the facility inlet air system was activated to provide dry air for repeatable inlet conditions. New flow conditioning hardware was installed in the facility inlet plenum tank, which greatly reduced the inlet turbulence. The new inlet can also be easily modified to accommodate 20- or 22-in.-diameter fans and compressors, so a variety of existing hardware from other facilities (such as Glenn's 9- by 15-Foot Low-Speed Wind Tunnel) can be tested in the Single-Stage Axial Compressor Facility. An exhaust line was also installed to provide bleed capability to remove the inlet boundary layer. To improve the operation and control of the facility, a new programmable logic controller (PLC) was installed to upgrade from hardwired relay logic to software logic. The PLC also enabled the usage of human-machine interface software to allow for easier operation of the facility and easier reconfiguration of the facility controls when

  6. Experimental Investigation – Magnetic Assisted Electro Discharge Machining

    Science.gov (United States)

    Kesava Reddy, Chirra; Manzoor Hussain, M.; Satyanarayana, S.; Krishna, M. V. S. Murali

    2018-04-01

    Emerging technology needs advanced machined parts with high strength and temperature resistance, high fatigue life at low production cost with good surface quality to fit into various industrial applications. Electro discharge machine is one of the extensively used machines to manufacture advanced machined parts which cannot be machined by other traditional machine with high precision and accuracy. Machining of DIN 17350-1.2080 (High Carbon High Chromium steel), using electro discharge machining has been discussed in this paper. In the present investigation an effort is made to use permanent magnet at various positions near the spark zone to improve surface quality of the machined surface. Taguchi methodology is used to obtain optimal choice for each machining parameter such as peak current, pulse duration, gap voltage and Servo reference voltage etc. Process parameters have significant influence on machining characteristics and surface finish. Improvement in surface finish is observed when process parameters are set at optimum condition under the influence of magnetic field at various positions.

  7. Electromagnetic linear machines with dual Halbach array design and analysis

    CERN Document Server

    Yan, Liang; Peng, Juanjuan; Zhang, Lei; Jiao, Zongxia

    2017-01-01

    This book extends the conventional two-dimensional (2D) magnet arrangement into 3D pattern for permanent magnet linear machines for the first time, and proposes a novel dual Halbach array. It can not only effectively increase the radial component of magnetic flux density and output force of tubular linear machines, but also significantly reduce the axial flux density, radial force and thus system vibrations and noises. The book is also the first to address the fundamentals and provide a summary of conventional arrays, as well as novel concepts for PM pole design in electric linear machines. It covers theoretical study, numerical simulation, design optimization and experimental works systematically. The design concept and analytical approaches can be implemented to other linear and rotary machines with similar structures. The book will be of interest to academics, researchers, R&D engineers and graduate students in electronic engineering and mechanical engineering who wish to learn the core principles, met...

  8. Quantum machine learning.

    Science.gov (United States)

    Biamonte, Jacob; Wittek, Peter; Pancotti, Nicola; Rebentrost, Patrick; Wiebe, Nathan; Lloyd, Seth

    2017-09-13

    Fuelled by increasing computer power and algorithmic advances, machine learning techniques have become powerful tools for finding patterns in data. Quantum systems produce atypical patterns that classical systems are thought not to produce efficiently, so it is reasonable to postulate that quantum computers may outperform classical computers on machine learning tasks. The field of quantum machine learning explores how to devise and implement quantum software that could enable machine learning that is faster than that of classical computers. Recent work has produced quantum algorithms that could act as the building blocks of machine learning programs, but the hardware and software challenges are still considerable.

  9. Asynchronized synchronous machines

    CERN Document Server

    Botvinnik, M M

    1964-01-01

    Asynchronized Synchronous Machines focuses on the theoretical research on asynchronized synchronous (AS) machines, which are "hybrids” of synchronous and induction machines that can operate with slip. Topics covered in this book include the initial equations; vector diagram of an AS machine; regulation in cases of deviation from the law of full compensation; parameters of the excitation system; and schematic diagram of an excitation regulator. The possible applications of AS machines and its calculations in certain cases are also discussed. This publication is beneficial for students and indiv

  10. DESIGN EVALUATIONS OF DOUBLE ROTOR SWITCHED RELUCTANCE MACHINE

    Directory of Open Access Journals (Sweden)

    C.V. ARAVIND

    2016-02-01

    Full Text Available The absence of magnets makes the reluctance machine typical for low cogging operations with the torque depending on the stator rotor interaction area. The air gap between stator pole and rotor pole gives a huge effect on the reluctance variation. The primitive double rotor switched reluctance machine lags to improvise the effect of the ripple value though the torque density is higher compared to conventional machines. An optimised circular hole position and dimensioned in the stator pole of lowers the torque ripple and reduce the acoustic noise as presented in this paper. A comparative evaluation of the conventional double rotor machine with this improved structure is done through numerical design and evaluations for the same sizing. It is found that the motor constant square density. It is found that the double rotor switched reluctance machine is improved by 140% to conventional machine.

  11. Transition towards energy efficient machine tools

    Energy Technology Data Exchange (ETDEWEB)

    Zein, Andre [Technische Univ. Braunschweig (Germany). Inst. fuer Werkzeugmaschinen und Fertigungstechnik

    2012-07-01

    Provides unique data about industrial trends affecting the energy demand of machine tools. Presents a comprehensive methodology to assess the energy efficiency of machining processes. Contains an integrated management concept to implement energy performance measures into existing industrial systems. Includes an industrial case study with two exemplary applications. Energy efficiency represents a cost-effective and immediate strategy of a sustainable development. Due to substantial environmental and economic implications, a strong emphasis is put on the electrical energy requirements of machine tools for metalworking processes. The improvement of energy efficiency is however confronted with diverse barriers, which sustain an energy efficiency gap of unexploited potential. The deficiencies lie in the lack of information about the actual energy requirements of machine tools, a minimum energy reference to quantify improvement potential and the possible actions to improve the energy demand. Therefore, a comprehensive concept for energy performance management of machine tools is developed which guides the transition towards energy efficient machine tools. It is structured in four innovative concept modules, which are embedded into step-by-step workflow models. The capability of the performance management concept is demonstrated in an automotive manufacturing environment. The target audience primarily comprises researchers and practitioners challenged to enhance energy efficiency in manufacturing. The book may also be beneficial for graduate students who want to specialize in this field.

  12. Technology of magnetic abrasive finishing in machining of difficult-to-machine alloy complex surface

    Directory of Open Access Journals (Sweden)

    Fujian MA

    2016-10-01

    Full Text Available The technology of magnetic abrasive finishing is one of the important finishing technologies. Combining with low-frequency vibration and ultrasonic vibration, it can attain higher precision, quality and efficiency. The characteristics and the related current research of magnetic abrasive finishing, vibration assisted magnetic abrasive finishing and ultrasonic assisted magnetic abrasive finishing are introduced. According to the characteristics of the difficult-to-machine alloy's complex surface, the important problems for further study are presented to realize the finishing of complex surface with the technology of magnetic abrasive finishing, such as increasing the machining efficiency by enhancing the magnetic flux density of machining gap and compounding of magnetic energy and others, establishing of the control function during machining and the process planning method for magnetic abrasive finishing of complex surface under the space geometry restraint of complex surface on magnetic pole, etc.

  13. Design of an ultraprecision computerized numerical control chemical mechanical polishing machine and its implementation

    Science.gov (United States)

    Zhang, Chupeng; Zhao, Huiying; Zhu, Xueliang; Zhao, Shijie; Jiang, Chunye

    2018-01-01

    The chemical mechanical polishing (CMP) is a key process during the machining route of plane optics. To improve the polishing efficiency and accuracy, a CMP model and machine tool were developed. Based on the Preston equation and the axial run-out error measurement results of the m circles on the tin plate, a CMP model that could simulate the material removal at any point on the workpiece was presented. An analysis of the model indicated that lower axial run-out error led to lower material removal but better polishing efficiency and accuracy. Based on this conclusion, the CMP machine was designed, and the ultraprecision gas hydrostatic guideway and rotary table as well as the Siemens 840Dsl numerical control system were incorporated in the CMP machine. To verify the design principles of machine, a series of detection and machining experiments were conducted. The LK-G5000 laser sensor was employed for detecting the straightness error of the gas hydrostatic guideway and the axial run-out error of the gas hydrostatic rotary table. A 300-mm-diameter optic was chosen for the surface profile machining experiments performed to determine the CMP efficiency and accuracy.

  14. Standard practice for verification of constant amplitude dynamic forces in an axial fatigue testing system

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This practice covers procedures for the dynamic verification of cyclic force amplitude control or measurement accuracy during constant amplitude testing in an axial fatigue testing system. It is based on the premise that force verification can be done with the use of a strain gaged elastic element. Use of this practice gives assurance that the accuracies of forces applied by the machine or dynamic force readings from the test machine, at the time of the test, after any user applied correction factors, fall within the limits recommended in Section 9. It does not address static accuracy which must first be addressed using Practices E 4 or equivalent. 1.2 Verification is specific to a particular test machine configuration and specimen. This standard is recommended to be used for each configuration of testing machine and specimen. Where dynamic correction factors are to be applied to test machine force readings in order to meet the accuracy recommended in Section 9, the verification is also specific to the c...

  15. Fundamental Study on Electrical Discharge Machining

    OpenAIRE

    Uno, Yoshiyuki; Nakajima, Toshikatsu; Endo, Osamu

    1989-01-01

    The generation mechanism of crater in electrical discharge machining is analyzed with a single pulse discharge device for alloy tool steel, black alumina ceramics, cermet and cemented carbide, investigating the gap voltage, the discharge current, the shape of crater, the wear of electrode and so on. The experimental analysis makes it clear that the shape of crater has a characteristic feature for the kind of workpiece. The shape of electrode, which changes with the wear by an electric spark, ...

  16. Fatigue reliability of structural members under combined axial mean and alternating stresses for AISI 1018, 1038, 4130 and 4340 steels

    International Nuclear Information System (INIS)

    Kececioglu, D.

    1977-01-01

    The failure governing strength distributions of round specimens subjected to a mean axial stress onto which alternating tensile and compressive axial stresses are superimposed, for 10 6 and 2x10 6 cycles of operation, are determined. AISI 1018, 1038, 4130 and 4340 steel 3/8-in. diameter, specimens are tested on an axial, Baldwin-Lima-Hamilton Universal Fatigue Testing Machine. Staircase-testing is used to determine the endurance strength distributions at various ratios of alternating to mean tensile stresses. Testing is accomplished at a sufficient number of ratios to enable the construction of a distributional, statistical Goodman strength diagram for each one of the four steels. A digital computer program of the Reliability Engineering Research Laboratory at The University of Arizona, Program LEAST, is used to determine the equation of the distributional Goodman diagram which best fits the loci of the experimental data at stress ratios between zero and infinity

  17. Investigation of multipactor breakdown in communication satellite microwave co-axial systems

    Science.gov (United States)

    Nagesh, S. K.; Revannasiddiah, D.; Shastry, S. V. K.

    2005-01-01

    Multipactor breakdown or multipactor discharge is a form of high frequency discharge that may occur in microwave components operating at very low pressures. Some RF components of multi-channel communication satellites have co-axial geometry and handle high RF power under near-vacuum conditions. The breakdown occurs due to secondary electron resonance, wherein electrons move back and forth in synchronism with the RF voltage across the gap between the inner and outer conductors of the co-axial structure. If the yield of secondary electrons from the walls of the co-axial structure is greater than unity, then the electron density increases with time and eventually leads to the breakdown. In this paper, the current due to the oscillating electrons in the co-axial geometry has been treated as a radially oriented Hertzian dipole. The electric field, due to this dipole, at any point in the coaxial structure, may then be determined by employing the dyadic Green's function technique. This field has been compared with the field that would exist in the absence of multipactor.

  18. Research on a novel high stiffness axial passive magnetic bearing for DGMSCMG

    International Nuclear Information System (INIS)

    Sun, Jinji; Wang, Chun'e; Le, Yun

    2016-01-01

    To increase the displacement stiffness and decrease power loss of double gimbals magnetically suspended control momentum gyro (DGMSCMG), this paper researches a new structure of axial passive magnetic bearing (APMB). Different from the existing APMB, the proposed APMB is composed of segmented permanent magnets and magnetic rings. The displacement stiffness and angular stiffness expressions are derived by equivalent magnetic circuit method and infinitesimal method based on the end magnetic flux. The relationships are analyzed between stiffness and structure parameters such as length of air gap, length of permanent magnet, height of permanent magnet and end length of magnetic ring. Besides, the axial displacement stiffness measurement method of the APMB is proposed, and it verified the correctness of proposed theoretical method. The DGMSCMG prototype is manufactured and the slow-down characteristic experiment is carried out, and the experimental result reflects the low power loss feature of the APMB. - Highlights: • A novel high stiffness axial passive magnetic bearing for DGMSCMG. • The proposed APMB is composed of segmented permanent magnets and magnetic rings. • The APMB is analyzed by EMCM and infinitesimal method based on the end magnetic flux. • The axial displacement stiffness measurement method of the APMB is proposed. • The DGMSCMG is manufactured and proved the correctness of theoretical analysis.

  19. Review of Axial Burnup Distribution Considerations for Burnup Credit Calculations

    International Nuclear Information System (INIS)

    Wagner, J.C.; DeHart, M.D.

    2000-01-01

    This report attempts to summarize and consolidate the existing knowledge on axial burnup distribution issues that are important to burnup credit criticality safety calculations. Recently released Nuclear Regulatory Commission (NRC) staff guidance permits limited burnup credit, and thus, has prompted resolution of the axial burnup distribution issue. The reactivity difference between the neutron multiplication factor (keff) calculated with explicit representation of the axial burnup distribution and keff calculated assuming a uniform axial burnup is referred to as the ''end effect.'' This end effect is shown to be dependent on many factors, including the axial-burnup profile, total accumulated burnup, cooling time, initial enrichment, assembly design, and the isotopics considered (i.e., actinide-only or actinides plus fission products). Axial modeling studies, efforts related to the development of axial-profile databases, and the determination of bounding axial profiles are also discussed. Finally, areas that could benefit from further efforts are identified

  20. On the problem of axial anomaly in supersymmetric gauge theories

    International Nuclear Information System (INIS)

    Kazakov, D.I.

    1984-01-01

    The explicit relation is found between the axial current obeying the Adler-Bardeen theorem and the supersymmetric one belonging to a supermultiplet. It is shown that the axial and superconformal anomalies are consistent in all orders of perturbation theory

  1. Cross-flow filtration and axial filtration

    International Nuclear Information System (INIS)

    Kraus, K.A.

    1974-01-01

    Two relatively novel alternative solid-liquid-separation techniques of filtration are discussed. In cross-flow filtration, the feed is pumped past the filtering surface. While in axial filtration the filter, mounted on a rotor, is moved with respect to the feed. While large-scale application of the axial filter is still in doubt, it permits with little expenditure of time and money, duplication of many hydrodynamic aspects of cross-flow filtration for fine-particle handling problems. The technique has been applied to municipal wastes, low-level radioactive waste treatment plant, lead removal from industrial wastes, removal of pulp-mill contaminants, textile-mill wastes, and pretreatment of saline waters by lime-soda process in preparation for hyperfiltration. Economics and energy requirements are also discussed

  2. Computerized axial tomography in traumatic cervical lesions

    International Nuclear Information System (INIS)

    Koyama, Tsunemaro

    1982-01-01

    Although plain computerized axial tomography cannot routinely demonstrate the spinal cord, it does provide excellent visualization of the bony outline of the spinal canal and vertebral column. So it should be reasonable to use this technique in cases of cervical traumatic disorders. In this paper we presented 10 cases of cervical traumatic lesions; 3 atlanto-axial dislocation, 2 cervical canal stenosis, 3 OPLL, 1 intramedullary hematoma and 1 C 2 -neurinoma. In some patients neurologic deficits were induced by cervical trauma. Bony lesions appeared more adequately deliniated than intraspinal lesions, however, in some cases intramedullary changes could also be demonstrated. The use of metrizamide with high resolution CT-scanner could improve the usefullness of this technique. (author)

  3. Ventajas de los motores de flujo axial

    Directory of Open Access Journals (Sweden)

    Alberto M Basanta Otero

    2011-03-01

    Full Text Available Es importante conocer sobre una familia de motores que a diferencia de los convencionales o tradicionales no presentanun flujo rotatorio radial, denominados motores de flujo axial. Dichos motores presentan altos valores de par motriz abajas velocidades, una alta eficiencia y alta densidad de potencia. Este trabajo constituye un breve análisis dealgunos motores de la referencia bibliográfica.  Is important to know about a family of motors that at difference whit the traditional, don't have a rotator radial flux,called, axial flux motors. These motors have high torque for low speed, high efficiency and high power density. Thiswork is a brief analysis of several motors of the bibliographic references.

  4. Magnetic field-assisted electrochemical discharge machining

    International Nuclear Information System (INIS)

    Cheng, Chih-Ping; Mai, Chao-Chuang; Wu, Kun-Ling; Hsu, Yu-Shan; Yan, Biing-Hwa

    2010-01-01

    Electrochemical discharge machining (ECDM) is an effective unconventional method for micromachining in non-conducting materials, such as glass, quartz and some ceramics. However, since the spark discharge performance becomes unpredictable as the machining depth increases, it is hard to achieve precision geometry and efficient machining rate in ECDM drilling. One of the main factors for this is the lack of sufficient electrolyte flow in the narrow gap between the tool and the workpiece. In this study a magnetohydrodynamic (MHD) convection, which enhances electrolyte circulation has been applied to the ECDM process in order to upgrade the machining accuracy and efficiency. During electrolysis in the presence of a magnetic field, the Lorenz force induces the charged ions to form a MHD convection. The MHD convection then forces the electrolyte into movement, thus enhancing circulation of electrolyte. Experimental results show that the MHD convection induced by the magnetic field can effectively enhance electrolyte circulation in the micro-hole, which contributes to higher machining efficiency. Micro-holes in glass with a depth of 450 µm are drilled in less than 20 s. At the same time, better electrolyte circulation can prevent deterioration of gas film quality with increasing machining depth, while ensuring stable electrochemical discharge. The improvement in the entrance diameter thus achieved was 23.8% while that in machining time reached 57.4%. The magnetic field-assisted approach proposed in the research does not require changes in the machining setup or electrolyte but has proved to achieve significant enhancement in both accuracy and efficiency of ECDM.

  5. Internal and external axial corner flows

    Science.gov (United States)

    Kutler, P.; Shankar, V.; Anderson, D. A.; Sorenson, R. L.

    1975-01-01

    The inviscid, internal, and external axial corner flows generated by two intersecting wedges traveling supersonically are obtained by use of a second-order shock-capturing, finite-difference approach. The governing equations are solved iteratively in conical coordinates to yield the complicated wave structure of the internal corner and the simple peripheral shock of the external corner. The numerical results for the internal flows compare favorably with existing experimental data.

  6. Axial gravity, massless fermions and trace anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Bonora, L. [International School for Advanced Studies (SISSA), Trieste (Italy); KEK, Tsukuba (Japan). KEK Theory Center; INFN, Sezione di Trieste (Italy); Cvitan, M.; Giaccari, S.; Stemberga, T. [Zagreb Univ. (Croatia). Dept. of Physics; Prester, P.D. [Rijeka Univ. (Croatia). Dept. of Physics; Pereira, A.D. [UERJ-Univ. Estadual do Rio de Janeiro (Brazil). Dept. de Fisica Teorica; UFF-Univ. Federal Fluminense, Niteroi (Brazil). Inst. de Fisica

    2017-08-15

    This article deals with two main topics. One is odd parity trace anomalies in Weyl fermion theories in a 4d curved background, the second is the introduction of axial gravity. The motivation for reconsidering the former is to clarify the theoretical background underlying the approach and complete the calculation of the anomaly. The reference is in particular to the difference between Weyl and massless Majorana fermions and to the possible contributions from tadpole and seagull terms in the Feynman diagram approach. A first, basic, result of this paper is that a more thorough treatment, taking account of such additional terms and using dimensional regularization, confirms the earlier result. The introduction of an axial symmetric tensor besides the usual gravitational metric is instrumental to a different derivation of the same result using Dirac fermions, which are coupled not only to the usual metric but also to the additional axial tensor. The action of Majorana and Weyl fermions can be obtained in two different limits of such a general configuration. The results obtained in this way confirm the previously obtained ones. (orig.)

  7. Axial gravity, massless fermions and trace anomalies

    International Nuclear Information System (INIS)

    Bonora, L.; Cvitan, M.; Giaccari, S.; Stemberga, T.; Prester, P.D.; Pereira, A.D.; UFF-Univ. Federal Fluminense, Niteroi

    2017-01-01

    This article deals with two main topics. One is odd parity trace anomalies in Weyl fermion theories in a 4d curved background, the second is the introduction of axial gravity. The motivation for reconsidering the former is to clarify the theoretical background underlying the approach and complete the calculation of the anomaly. The reference is in particular to the difference between Weyl and massless Majorana fermions and to the possible contributions from tadpole and seagull terms in the Feynman diagram approach. A first, basic, result of this paper is that a more thorough treatment, taking account of such additional terms and using dimensional regularization, confirms the earlier result. The introduction of an axial symmetric tensor besides the usual gravitational metric is instrumental to a different derivation of the same result using Dirac fermions, which are coupled not only to the usual metric but also to the additional axial tensor. The action of Majorana and Weyl fermions can be obtained in two different limits of such a general configuration. The results obtained in this way confirm the previously obtained ones. (orig.)

  8. Golimumab for the treatment of axial spondyloarthritis.

    Science.gov (United States)

    Palazzi, Carlo; D'angelo, Salvatore; Gilio, Michele; Leccese, Pietro; Padula, Angela; Olivieri, Ignazio

    2017-01-01

    Anti-TNF drugs have represented an epochal revolution in the treatment of rheumatoid arthritis and spondyloarthritis. In the field of axial spondyloarthritis, golimumab, a fully human monoclonal anti-TNFα administered subcutaneously every 4 weeks, has shown significant efficacy and good safety in patients with ankylosing spondylitis. More recently, it was also indicated as an effective treatment for patients suffering from non-radiographic axial spondyloarthitits. Areas covered: A systematic literature search was completed, using the largest electronic databases (Medline, Embase and Cochrane), with the aim to review all data concerning the administration of golimumab in patients suffering from axial spondyloartritis. Expert opinion: In the 16-week GO-AHEAD study, golimumab was effective in patients with non-radiographic spondyloarthritis with high levels of CRP and/or positive MRI findings, but not in subjects with both negative CRP and MRI. This finding allows for the addressing the of anti-TNF treatment more specifically. Preliminary data concerning an open-label extension of the GO-AHEAD study outlined the high retention-rate of the drug at 52 weeks. The production of antibodies against golimumab is rare and it seems to exert scarce influence on the drug performances. In conclusion, golimumab appears as a very useful and well tolerated anti-TNF agent.

  9. Axial Dispersion during Hanford Saltcake Washing

    International Nuclear Information System (INIS)

    Josephson, Gary B.; Geeting, John GH; Lessor, Delbert L.; Barton, William B.

    2006-01-01

    Clean up of Hanford salt cake wastes begins with dissolution retrieval of the sodium rich salts that make up the dominant majority of mass in the tanks. Water moving through the porous salt cake dissolves the soluble components and also displaces the soluble radionuclides (e.g. 137Cs and 99TcO4- ). The separation that occurs from this displacement, known as Selective dissolution, is an important component in Hanford?s pretreatment of low activity wastes for subsequent Supplemental treatment. This paper describes lab scale testing conducted to evaluate Selective dissolution of cesium from non-radioactive Hanford tank 241-S-112 salt cake simulant containing the primary chemicals found the actual tank. An modified axial dispersion model with increasing axial dispersion was developed to predict cesium removal. The model recognizes that water dissolves the salt cake during washing, which causes an increase in the axial dispersion during the wash. This model was subsequently compared with on-line cesium measurements from the retrieval of tank 241-S-112. The model had remarkably good agreement with both the lab scale and full scale data

  10. Bessel beam CARS of axially structured samples

    Science.gov (United States)

    Heuke, Sandro; Zheng, Juanjuan; Akimov, Denis; Heintzmann, Rainer; Schmitt, Michael; Popp, Jürgen

    2015-06-01

    We report about a Bessel beam CARS approach for axial profiling of multi-layer structures. This study presents an experimental implementation for the generation of CARS by Bessel beam excitation using only passive optical elements. Furthermore, an analytical expression is provided describing the generated anti-Stokes field by a homogeneous sample. Based on the concept of coherent transfer functions, the underling resolving power of axially structured geometries is investigated. It is found that through the non-linearity of the CARS process in combination with the folded illumination geometry continuous phase-matching is achieved starting from homogeneous samples up to spatial sample frequencies at twice of the pumping electric field wave. The experimental and analytical findings are modeled by the implementation of the Debye Integral and scalar Green function approach. Finally, the goal of reconstructing an axially layered sample is demonstrated on the basis of the numerically simulated modulus and phase of the anti-Stokes far-field radiation pattern.

  11. Dynamic control of knee axial deformities

    Directory of Open Access Journals (Sweden)

    E. E. Malyshev

    2013-01-01

    Full Text Available The authors have evaluated the clinical examination of the patients with axial malalignments in the knee by the original method and device which was named varovalgometer. The measurements were conducted by tension of the cord through the spina iliaca anterior superior and the middle of the lower pole of patella. The deviation of the center of the ankle estimated by metal ruler which was positioned perpendicular to the lower leg axis on the level of the ankle joint line. The results of comparison of our method and computer navigation in 53 patients during the TKA show no statistically significant varieties but they differ by average 5° of valgus in clinical examination in comparison with mechanical axis which was identified by computer navigation. The dynamic control of axial malalignment can be used in clinical practice for estimation of the results of treatment of pathology with axial deformities in the knee; for the control of reduction and secondary displacement of the fractures around the knee; for assessment of instability; in planning of correctional osteotomies and intraoperative control of deformity correction; for estimation of Q angle in subluxation and recurrent dislocation of patella; in planning of TKA; during the growth of child it allows to assess the progression of deformity.

  12. Gap and density theorems

    CERN Document Server

    Levinson, N

    1940-01-01

    A typical gap theorem of the type discussed in the book deals with a set of exponential functions { \\{e^{{{i\\lambda}_n} x}\\} } on an interval of the real line and explores the conditions under which this set generates the entire L_2 space on this interval. A typical gap theorem deals with functions f on the real line such that many Fourier coefficients of f vanish. The main goal of this book is to investigate relations between density and gap theorems and to study various cases where these theorems hold. The author also shows that density- and gap-type theorems are related to various propertie

  13. Bridging the Gap

    DEFF Research Database (Denmark)

    Kramer Overgaard, Majken; Broeng, Jes; Jensen, Monika Luniewska

    Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures.......Bridging the Gap (BtG) is a 2-year project funded by The Danish Industry Foundation. The goal of Bridging the Gap has been to create a new innovation model which will increase the rate at which Danish universities can spinout new technology ventures....

  14. Axial anomaly at finite temperature and finite density

    International Nuclear Information System (INIS)

    Qian Zhixin; Su Rukeng; Yu, P.K.N.

    1994-01-01

    The U(1) axial anomaly in a hot fermion medium is investigated by using the real time Green's function method. After calculating the lowest order triangle diagrams, we find that finite temperature as well as finite fermion density does not affect the axial anomaly. The higher order corrections for the axial anomaly are discussed. (orig.)

  15. The deep structure of Axial Volcano

    Science.gov (United States)

    West, Michael Edwin

    The subsurface structure of Axial Volcano, near the intersection of the Juan de Fuca Ridge and the Cobb-Eickelberg seamount chain in the northeast Pacific, is imaged from an active source seismic experiment. At a depth of 2.25 to 3.5 km beneath Axial lies an 8 km x 12 km region of very low seismic velocities that can only be explained by the presence of magma. In the center of this magma storage chamber at 2--3.5 km below sea floor, the crust is at least 10--20% melt. At depths of 4--5 km there is evidence of additional low concentrations of magma (a few percent) over a larger area. In total, 5--11 km3 of magma are stored in the mid-crust beneath Axial. This is more melt than has been positively identified under any basaltic volcano on Earth. It is also far more than the 0.1--0.2 km3 emplaced during the 1998 eruption. The implied residence time in the magma reservoir of a few hundred to a few thousand years agrees with geochemical trends which suggest prolonged storage and mixing of magmas. The large volume of melt bolsters previous observations that Axial provides much of the material to create crust along its 50 km rift zones. A high velocity ring-shaped feature sits above the magma chamber just outside the caldera walls. This feature is believed to be the result of repeated dike injections from the magma body to the surface during the construction of the volcanic edifice. A rapid change in crustal thickness from 8 to 11 km within 15 km of the caldera implies focused delivery of melt from the mantle. The high flux of magma suggests that melting occurs deeper in the mantle than along the nearby ridge. Melt supply to the volcano is not connected to any plumbing system associated with the adjacent segments of the Juan de Fuca Ridge. This suggests that, despite Axial's proximity to the ridge, the Cobb hot spot currently drives the supply of melt to the volcano.

  16. Diffusive boundary layers at the bottom of gaps and cracks

    Science.gov (United States)

    Etzold, Merlin A.; Landel, Julien R.; Dalziel, Stuart B.

    2017-11-01

    This work is motivated by the chemical decontamination of droplets of chemical warfare agents trapped in the gaps and cracks found in most man-made objects. We consider axial laminar flow within gaps with both straight and angled walls. We study the diffusive mass transfer from a source (e.g. a droplet surface) located at the bottom of the gap. This problem is similar to boundary layers and Graetz-type problems (heat transfer in pipe flow) with the added complication of a non-uniform lateral concentration profile due to the lateral variation of the velocity profile. We present 3D solutions for the diffusive boundary layer and demonstrate that a 2D mean-field model, for which we calculate series and similarity solutions, captures the essential physics. We demonstrate the immediate practical relevance of our findings by comparing decontamination of a droplet located in a gap and on an exposed surface.

  17. Pattern recognition & machine learning

    CERN Document Server

    Anzai, Y

    1992-01-01

    This is the first text to provide a unified and self-contained introduction to visual pattern recognition and machine learning. It is useful as a general introduction to artifical intelligence and knowledge engineering, and no previous knowledge of pattern recognition or machine learning is necessary. Basic for various pattern recognition and machine learning methods. Translated from Japanese, the book also features chapter exercises, keywords, and summaries.

  18. Support vector machines applications

    CERN Document Server

    Guo, Guodong

    2014-01-01

    Support vector machines (SVM) have both a solid mathematical background and good performance in practical applications. This book focuses on the recent advances and applications of the SVM in different areas, such as image processing, medical practice, computer vision, pattern recognition, machine learning, applied statistics, business intelligence, and artificial intelligence. The aim of this book is to create a comprehensive source on support vector machine applications, especially some recent advances.

  19. The Newest Machine Material

    International Nuclear Information System (INIS)

    Seo, Yeong Seop; Choe, Byeong Do; Bang, Meong Sung

    2005-08-01

    This book gives descriptions of machine material with classification of machine material and selection of machine material, structure and connection of material, coagulation of metal and crystal structure, equilibrium diagram, properties of metal material, elasticity and plasticity, biopsy of metal, material test and nondestructive test. It also explains steel material such as heat treatment of steel, cast iron and cast steel, nonferrous metal materials, non metallic materials, and new materials.

  20. Introduction to machine learning

    OpenAIRE

    Baştanlar, Yalın; Özuysal, Mustafa

    2014-01-01

    The machine learning field, which can be briefly defined as enabling computers make successful predictions using past experiences, has exhibited an impressive development recently with the help of the rapid increase in the storage capacity and processing power of computers. Together with many other disciplines, machine learning methods have been widely employed in bioinformatics. The difficulties and cost of biological analyses have led to the development of sophisticated machine learning app...

  1. Machinability of advanced materials

    CERN Document Server

    Davim, J Paulo

    2014-01-01

    Machinability of Advanced Materials addresses the level of difficulty involved in machining a material, or multiple materials, with the appropriate tooling and cutting parameters.  A variety of factors determine a material's machinability, including tool life rate, cutting forces and power consumption, surface integrity, limiting rate of metal removal, and chip shape. These topics, among others, and multiple examples comprise this research resource for engineering students, academics, and practitioners.

  2. Machining of titanium alloys

    CERN Document Server

    2014-01-01

    This book presents a collection of examples illustrating the resent research advances in the machining of titanium alloys. These materials have excellent strength and fracture toughness as well as low density and good corrosion resistance; however, machinability is still poor due to their low thermal conductivity and high chemical reactivity with cutting tool materials. This book presents solutions to enhance machinability in titanium-based alloys and serves as a useful reference to professionals and researchers in aerospace, automotive and biomedical fields.

  3. Effect of axial diffusional delays on the overall fission gas release

    International Nuclear Information System (INIS)

    Pedersen, N.K.

    1983-01-01

    In fission gas release modeling, it is normally assumed that any locally released gas mixes instantly and perfectly with other gases throughout the internal rod void volume. The present work investigates the consequences of the assumption that perfect mixing is dependent on diffusion, although the subassumption is maintained that pressure equilibrium is instantly achieved. In other words, when a burst of gas release occurs at any axial location, sufficient local accommodation takes place throughout the rod to eliminate any pressure gradients, but due to the narrowness of the passages through fuel cracks and fuel-cladding gap, concentration gradients may still prevail. Diffusion coefficients for the subsequent concentration equilibration are derived from classical theories. Application of one-dimensional diffusion theory is straightforward, but the lack of knowledge of the effective width of the axial passage introduces an uncertainty

  4. A new strategy of axial power distribution control based on three axial offsets concept

    International Nuclear Information System (INIS)

    Shimazu, Yoichiro

    2009-01-01

    We have proposed a very simple control procedure for axial xenon oscillation control based on a characteristic trajectory. The trajectory is drawn by three offsets of power distributions, namely, AOp, AOi and AOx. They are defined as the offset of axial power distribution, the offset of the power distribution under which the current iodine distribution is obtained as the equilibrium and that for xenon distribution, respectively. When these offsets are plotted on X-Y plane for (AOp-AOx, AOi-AOx) the trajectory draws a quite characteristic ellipse (or an elliptic spiral). On the other hands, Constant Axial Offset Control (CAOC) procedure is adopted as axial power distribution control strategy during both base load and load following operations in domestic PWRs. In the previous paper, we have presented an innovative procedure of axial power distribution control during load following in PWRs based on this trajectory such that the AOp-AOx is to be controlled to zero when the value deviates the pre-determined limiting values. In this paper we propose a modified control strategy to get more stability of axial power distributions. In this strategy, we control the trajectory to be close to the major axis of the ellipse when the power distribution reaches the limiting values. In other words, the plot is not controlled only to reduce AOp-AOx but also AOi-AOx is taken into account at the same time. It is known that when the plot is controlled to the major axis, it means that the point gives the peak position of axial xenon oscillation. Therefore xenon oscillation will not increase its amplitude any more. Thus more stable axial power distribution control is attained. This kind of design concept is quite important especially for the future PWRs with elongated fuel length and longer core life. Because in a longer effective core and also the longer core life, it has been known that the stability of axial xenon oscillation becomes more unstable. In this paper, some simulation

  5. Intrinsic carpal ligaments on MR and multidetector CT arthrography: comparison of axial and axial oblique planes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ryan K.L.; Griffith, James F.; Ng, Alex W.H.; Law, Eric K.C. [The Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince Of Wales Hospital, Hong Kong (China); Tse, W.L.; Wong, Clara W.Y.; Ho, P.C. [The Chinese University of Hong Kong, Department of Orthopedics and Traumatology, Prince Of Wales Hospital, Hong Kong (China)

    2017-03-15

    To compare axial and oblique axial planes on MR arthrography (MRA) and multidetector CT arthrography (CTA) to evaluate dorsal and volar parts of scapholunate (SLIL) and lunotriquetral interosseous (LTIL) ligaments. Nine cadaveric wrists of five male subjects were studied. The visibility of dorsal and volar parts of the SLIL and LTIL was graded semi-quantitatively (good, intermediate, poor) on MRA and CTA. The presence of a ligament tear was determined on arthrosocopy and sensitivity, specificity and accuracy of tear detection were calculated. Oblique axial imaging was particularly useful for delineating dorsal and volar parts of the LTIL on MRA with overall 'good' visibility increased from 11 % to 78 %. The accuracy of MRA and CTA in revealing SLIL and LTIL tear was higher using the oblique axial plane. The overall accuracy for detecting SLIL tear on CTA improved from 94 % to 100 % and from 89 % to 94 % on MRA; the overall accuracy of detecting LTIL tear on CTA improved from 89 % to 100 % and from 72 % to 89 % on MRA Oblique axial imaging during CT and MR arthrography improves detection of tears in the dorsal and volar parts of both SLIL and LTIL. (orig.)

  6. Evolution of the mirror machine

    International Nuclear Information System (INIS)

    Damm, C.C.

    1983-01-01

    The history of the magnetic-mirror approach to a fusion reactor is primarily the history of our understanding and control of several crucial physics issues, coupled with progress in the technology of heating and confining a reacting plasma. The basic requirement of an MHD-stable plasma equilibrium was achieved following the early introduction of minimum-B multipolar magnetic fields. In refined form, the same magnetic-well principle carries over to our present experiments and to reactor designs. The higher frequency microinstabilities, arising from the non-Maxwellian particle distributions inherent in mirror machines, have gradually come under control as theoretical prescriptions for distribution functions have been applied in the experiments. Even with stability, the classical plasma leakage through the mirrors posed a serious question for reactor viability until the principle of electrostatic axial stoppering was applied in the tandem mirror configuration. Experiments to test this principle successfully demonstrated the substantial improvement in confinement predicted. Concurrent with advances in mirror plasma physics, development of both high-power neutral beam injectors and high-speed vacuum pumping techniques has played a crucial role in ongoing experiments. Together with superconducting magnets, cryogenic pumping, and high-power radiofrequency heating, these technologies have evolved to a level that extrapolates readily to meet the requirements of a tandem mirror fusion reactor

  7. Tribology in machine design

    CERN Document Server

    Stolarski, Tadeusz

    1999-01-01

    ""Tribology in Machine Design is strongly recommended for machine designers, and engineers and scientists interested in tribology. It should be in the engineering library of companies producing mechanical equipment.""Applied Mechanics ReviewTribology in Machine Design explains the role of tribology in the design of machine elements. It shows how algorithms developed from the basic principles of tribology can be used in a range of practical applications within mechanical devices and systems.The computer offers today's designer the possibility of greater stringen

  8. Induction machine handbook

    CERN Document Server

    Boldea, Ion

    2002-01-01

    Often called the workhorse of industry, the advent of power electronics and advances in digital control are transforming the induction motor into the racehorse of industrial motion control. Now, the classic texts on induction machines are nearly three decades old, while more recent books on electric motors lack the necessary depth and detail on induction machines.The Induction Machine Handbook fills industry's long-standing need for a comprehensive treatise embracing the many intricate facets of induction machine analysis and design. Moving gradually from simple to complex and from standard to

  9. Chaotic Boltzmann machines

    Science.gov (United States)

    Suzuki, Hideyuki; Imura, Jun-ichi; Horio, Yoshihiko; Aihara, Kazuyuki

    2013-01-01

    The chaotic Boltzmann machine proposed in this paper is a chaotic pseudo-billiard system that works as a Boltzmann machine. Chaotic Boltzmann machines are shown numerically to have computing abilities comparable to conventional (stochastic) Boltzmann machines. Since no randomness is required, efficient hardware implementation is expected. Moreover, the ferromagnetic phase transition of the Ising model is shown to be characterised by the largest Lyapunov exponent of the proposed system. In general, a method to relate probabilistic models to nonlinear dynamics by derandomising Gibbs sampling is presented. PMID:23558425

  10. Electrical machines & drives

    CERN Document Server

    Hammond, P

    1985-01-01

    Containing approximately 200 problems (100 worked), the text covers a wide range of topics concerning electrical machines, placing particular emphasis upon electrical-machine drive applications. The theory is concisely reviewed and focuses on features common to all machine types. The problems are arranged in order of increasing levels of complexity and discussions of the solutions are included where appropriate to illustrate the engineering implications. This second edition includes an important new chapter on mathematical and computer simulation of machine systems and revised discussions o

  11. Nanocomposites for Machining Tools

    Directory of Open Access Journals (Sweden)

    Daria Sidorenko

    2017-10-01

    Full Text Available Machining tools are used in many areas of production. To a considerable extent, the performance characteristics of the tools determine the quality and cost of obtained products. The main materials used for producing machining tools are steel, cemented carbides, ceramics and superhard materials. A promising way to improve the performance characteristics of these materials is to design new nanocomposites based on them. The application of micromechanical modeling during the elaboration of composite materials for machining tools can reduce the financial and time costs for development of new tools, with enhanced performance. This article reviews the main groups of nanocomposites for machining tools and their performance.

  12. Machine listening intelligence

    Science.gov (United States)

    Cella, C. E.

    2017-05-01

    This manifesto paper will introduce machine listening intelligence, an integrated research framework for acoustic and musical signals modelling, based on signal processing, deep learning and computational musicology.

  13. Machine learning with R

    CERN Document Server

    Lantz, Brett

    2013-01-01

    Written as a tutorial to explore and understand the power of R for machine learning. This practical guide that covers all of the need to know topics in a very systematic way. For each machine learning approach, each step in the process is detailed, from preparing the data for analysis to evaluating the results. These steps will build the knowledge you need to apply them to your own data science tasks.Intended for those who want to learn how to use R's machine learning capabilities and gain insight from your data. Perhaps you already know a bit about machine learning, but have never used R; or

  14. Rotating electrical machines

    CERN Document Server

    Le Doeuff, René

    2013-01-01

    In this book a general matrix-based approach to modeling electrical machines is promulgated. The model uses instantaneous quantities for key variables and enables the user to easily take into account associations between rotating machines and static converters (such as in variable speed drives).   General equations of electromechanical energy conversion are established early in the treatment of the topic and then applied to synchronous, induction and DC machines. The primary characteristics of these machines are established for steady state behavior as well as for variable speed scenarios. I

  15. Machining variability impacts on the strength of a 'chair-side' CAD-CAM ceramic.

    LENUS (Irish Health Repository)

    Addison, Owen

    2012-08-01

    To develop a novel methodology to generate specimens for bi-axial flexure strength (BFS) determination from a \\'chair-side\\' CAD-CAM feldspathic ceramic with surface defect integrals analogous to the clinical state. The hypotheses tested were: BFS and surface roughness (R(a)) are independent of machining variability introduced by the renewal or deterioration of form-grinding tools and that a post-machining annealing cycle would significantly modify BFS.

  16. Are there intelligent Turing machines?

    OpenAIRE

    Bátfai, Norbert

    2015-01-01

    This paper introduces a new computing model based on the cooperation among Turing machines called orchestrated machines. Like universal Turing machines, orchestrated machines are also designed to simulate Turing machines but they can also modify the original operation of the included Turing machines to create a new layer of some kind of collective behavior. Using this new model we can define some interested notions related to cooperation ability of Turing machines such as the intelligence quo...

  17. Bridge the Gap

    DEFF Research Database (Denmark)

    Marselis, Randi

    2017-01-01

    This article focuses on photo projects organised for teenage refugees by the Society for Humanistic Photography (Berlin, Germany). These projects, named Bridge the Gap I (2015), and Bridge the Gap II (2016), were carried out in Berlin and brought together teenagers with refugee and German...

  18. Bridging a Cultural Gap

    Science.gov (United States)

    Leviatan, Talma

    2008-01-01

    There has been a broad wave of change in tertiary calculus courses in the past decade. However, the much-needed change in tertiary pre-calculus programmes--aimed at bridging the gap between high-school mathematics and tertiary mathematics--is happening at a far slower pace. Following a discussion on the nature of the gap and the objectives of a…

  19. Understanding the Gender Gap.

    Science.gov (United States)

    Goldin, Claudia

    1985-01-01

    Despite the great influx of women into the labor market, the gap between men's and women's wages has remained stable at 40 percent since 1950. Analysis of labor data suggests that this has occurred because women's educational attainment compared to men has declined. Recently, however, the wage gap has begun to narrow, and this will probably become…

  20. Bridging the Transition Gap

    Science.gov (United States)

    2013-05-23

    period and provide recommendations to guide future research and policy development. 4 DEFINING THE TRANSITIONAL SECURITY GAP There have been...BRIDGING THE TRANSITION GAP A Monograph by MAJ J.D. Hansen United States Army School of Advanced Military Studies United States Army...suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704

  1. Investigation of Turbulent Tip Leakage Vortex in an Axial Water Jet Pump with Large Eddy Simulation

    Science.gov (United States)

    Hah, Chunill; Katz, Joseph

    2012-01-01

    Detailed steady and unsteady numerical studies were performed to investigate tip clearance flow in an axial water jet pump. The primary objective is to understand physics of unsteady tip clearance flow, unsteady tip leakage vortex, and cavitation inception in an axial water jet pump. Steady pressure field and resulting steady tip leakage vortex from a steady flow analysis do not seem to explain measured cavitation inception correctly. The measured flow field near the tip is unsteady and measured cavitation inception is highly transient. Flow visualization with cavitation bubbles shows that the leakage vortex is oscillating significantly and many intermittent vortex ropes are present between the suction side of the blade and the tip leakage core vortex. Although the flow field is highly transient, the overall flow structure is stable and a characteristic frequency seems to exist. To capture relevant flow physics as much as possible, a Reynolds-averaged Navier-Stokes (RANS) calculation and a Large Eddy Simulation (LES) were applied for the current investigation. The present study reveals that several vortices from the tip leakage vortex system cross the tip gap of the adjacent blade periodically. Sudden changes in local pressure field inside tip gap due to these vortices create vortex ropes. The instantaneous pressure filed inside the tip gap is drastically different from that of the steady flow simulation. Unsteady flow simulation which can calculate unsteady vortex motion is necessary to calculate cavitation inception accurately even at design flow condition in such a water jet pump.

  2. Sensitivity analysis of power depression and axial power factor effect on fuel pin to temperature and related properties distribution

    International Nuclear Information System (INIS)

    Suwardi, S.

    2001-01-01

    The presented paper is a preliminary step to evaluate the effect of radial and axial distribution of power generation on thermal analysis of whole fuel pin model with large L/D ratio. The model takes into account both radial and axial distribution of power generation due to power depression and core geometry, temperature and microstructure dependent on thermal conductivity. The microstructure distribution and the gap conductance for typical steady-state situation are given for the sensitivity analysis. The temperature and thermal conductivity distribution along the radial and axial directions obtained by different power distribution is used to indicate the sensitivity of power depression and power factor on thermal aspect. The evaluation is made for one step of incremental time and steady state approach is used. The analysis has been performed using a finite element-finite difference model. The result for typical reactor fuel shows that the sensitivity is too important to be omitted in thermal model

  3. Inverse axial mounting stiffness design for lithographic projection lenses.

    Science.gov (United States)

    Wen-quan, Yuan; Hong-bo, Shang; Wei, Zhang

    2014-09-01

    In order to balance axial mounting stiffness of lithographic projection lenses and the image quality under dynamic working conditions, an easy inverse axial mounting stiffness design method is developed in this article. Imaging quality deterioration at the wafer under different axial vibration levels is analyzed. The desired image quality can be determined according to practical requirements, and axial vibrational tolerance of each lens is solved with the damped least-squares method. Based on adaptive interval adjustment, a binary search algorithm, and the finite element method, the axial mounting stiffness of each lens can be traveled in a large interval, and converges to a moderate numerical solution which makes the axial vibrational amplitude of the lens converge to its axial vibrational tolerance. Model simulation is carried out to validate the effectiveness of the method.

  4. Axial sesamoiditis in the horse: A review

    Directory of Open Access Journals (Sweden)

    Christelle Le Roux

    2018-03-01

    Full Text Available Axial sesamoiditis or osteitis of the proximal sesamoid bones (PSBs in the horse is described as a rare condition. The cause remains unknown and speculative, with vascular, infectious, and traumatic aetiologies implicated. It is specifically associated with injury of the palmar or plantar ligament (PL, also known as the intersesamoidean ligament. Imaging findings are generally rewarding and radiological changes are typical, if not pathognomonic, for the condition. Lesions consist of bone lysis at the apical to mid-body axial margins of the PSBs, with variable degrees of joint effusion. Radiographic technique warrants careful attention to make a diagnosis, and exposure factors may need to be adjusted. Perineural, intra-articular and intra-thecal anaesthesia does not seem to provide consistent improvement of lameness in these cases, with literature reporting inconsistent findings. Ultrasonographic findings include digital flexor sheath effusion, loss of the normal fibre structure of the PL at its attachment to the PSBs, abnormal echogenicity or change in thickness of the PL, and irregular hyperechoic cortical margins of the axial margins of the PSBs. Scintigraphy, computed tomography and magnetic resonance imaging, although not necessary to make a diagnosis, may add valuable information regarding the location and extent of lesions. The prognosis remains guarded to poor for return to athletic function. The focus of this paper is a comprehensive review of the proposed aetiopathogenesis of the condition, the prognosis, and a summary of the literature findings with focus on the notable diagnostic imaging features, including radiography, ultrasonography, scintigraphy, computed tomography and magnetic resonance imaging.

  5. Axial Tomography from Digitized Real Time Radiography

    Science.gov (United States)

    Zolnay, A. S.; McDonald, W. M.; Doupont, P. A.; McKinney, R. L.; Lee, M. M.

    1985-01-18

    Axial tomography from digitized real time radiographs provides a useful tool for industrial radiography and tomography. The components of this system are: x-ray source, image intensifier, video camera, video line extractor and digitizer, data storage and reconstruction computers. With this system it is possible to view a two dimensional x-ray image in real time at each angle of rotation and select the tomography plane of interest by choosing which video line to digitize. The digitization of a video line requires less than a second making data acquisition relatively short. Further improvements on this system are planned and initial results are reported.

  6. Disordered axial movement in Parkinson's disease.

    OpenAIRE

    Steiger, M J; Thompson, P D; Marsden, C D

    1996-01-01

    Axial motor impairments are a common cause of disability in patients with Parkinson's disease, become more prominent with longer disease duration, and have been said to be less responsive to levodopa replacement therapy. The ability to turn in bed while lying supine before and after dopaminergic stimulation was studied in a group of 36 patients with Parkinson's disease; 23 were in Hoehn and Yahr stages 3-5 when "off", and 13 were in stages 1-2. Turning was also compared with postural stabilit...

  7. Digital enhancement of computerized axial tomograms

    Science.gov (United States)

    Roberts, E., Jr.

    1978-01-01

    A systematic evaluation has been conducted of certain digital image enhancement techniques performed in image space. Three types of images have been used, computer generated phantoms, tomograms of a synthetic phantom, and axial tomograms of human anatomy containing images of lesions, artificially introduced into the tomograms. Several types of smoothing, sharpening, and histogram modification have been explored. It has been concluded that the most useful enhancement techniques are a selective smoothing of singular picture elements, combined with contrast manipulation. The most useful tool in applying these techniques is the gray-scale histogram.

  8. Microsoft Azure machine learning

    CERN Document Server

    Mund, Sumit

    2015-01-01

    The book is intended for those who want to learn how to use Azure Machine Learning. Perhaps you already know a bit about Machine Learning, but have never used ML Studio in Azure; or perhaps you are an absolute newbie. In either case, this book will get you up-and-running quickly.

  9. The Hooey Machine.

    Science.gov (United States)

    Scarnati, James T.; Tice, Craig J.

    1992-01-01

    Describes how students can make and use Hooey Machines to learn how mechanical energy can be transferred from one object to another within a system. The Hooey Machine is made using a pencil, eight thumbtacks, one pushpin, tape, scissors, graph paper, and a plastic lid. (PR)

  10. Nanocomposites for Machining Tools

    DEFF Research Database (Denmark)

    Sidorenko, Daria; Loginov, Pavel; Mishnaevsky, Leon

    2017-01-01

    Machining tools are used in many areas of production. To a considerable extent, the performance characteristics of the tools determine the quality and cost of obtained products. The main materials used for producing machining tools are steel, cemented carbides, ceramics and superhard materials...

  11. A nucleonic weighing machine

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    The design and operation of a nucleonic weighing machine fabricated for continuous weighing of material over conveyor belt are described. The machine uses a 40 mCi cesium-137 line source and a 10 litre capacity ionization chamber. It is easy to maintain as there are no moving parts. It can also be easily removed and reinstalled. (M.G.B.)

  12. An asymptotical machine

    Science.gov (United States)

    Cristallini, Achille

    2016-07-01

    A new and intriguing machine may be obtained replacing the moving pulley of a gun tackle with a fixed point in the rope. Its most important feature is the asymptotic efficiency. Here we obtain a satisfactory description of this machine by means of vector calculus and elementary trigonometry. The mathematical model has been compared with experimental data and briefly discussed.

  13. Machine learning with R

    CERN Document Server

    Lantz, Brett

    2015-01-01

    Perhaps you already know a bit about machine learning but have never used R, or perhaps you know a little R but are new to machine learning. In either case, this book will get you up and running quickly. It would be helpful to have a bit of familiarity with basic programming concepts, but no prior experience is required.

  14. The deleuzian abstract machines

    DEFF Research Database (Denmark)

    Werner Petersen, Erik

    2005-01-01

    To most people the concept of abstract machines is connected to the name of Alan Turing and the development of the modern computer. The Turing machine is universal, axiomatic and symbolic (E.g. operating on symbols). Inspired by Foucault, Deleuze and Guattari extended the concept of abstract...

  15. Human Machine Learning Symbiosis

    Science.gov (United States)

    Walsh, Kenneth R.; Hoque, Md Tamjidul; Williams, Kim H.

    2017-01-01

    Human Machine Learning Symbiosis is a cooperative system where both the human learner and the machine learner learn from each other to create an effective and efficient learning environment adapted to the needs of the human learner. Such a system can be used in online learning modules so that the modules adapt to each learner's learning state both…

  16. Precision machining commercialization

    International Nuclear Information System (INIS)

    1978-01-01

    To accelerate precision machining development so as to realize more of the potential savings within the next few years of known Department of Defense (DOD) part procurement, the Air Force Materials Laboratory (AFML) is sponsoring the Precision Machining Commercialization Project (PMC). PMC is part of the Tri-Service Precision Machine Tool Program of the DOD Manufacturing Technology Five-Year Plan. The technical resources supporting PMC are provided under sponsorship of the Department of Energy (DOE). The goal of PMC is to minimize precision machining development time and cost risk for interested vendors. PMC will do this by making available the high precision machining technology as developed in two DOE contractor facilities, the Lawrence Livermore Laboratory of the University of California and the Union Carbide Corporation, Nuclear Division, Y-12 Plant, at Oak Ridge, Tennessee

  17. Introduction to machine learning.

    Science.gov (United States)

    Baştanlar, Yalin; Ozuysal, Mustafa

    2014-01-01

    The machine learning field, which can be briefly defined as enabling computers make successful predictions using past experiences, has exhibited an impressive development recently with the help of the rapid increase in the storage capacity and processing power of computers. Together with many other disciplines, machine learning methods have been widely employed in bioinformatics. The difficulties and cost of biological analyses have led to the development of sophisticated machine learning approaches for this application area. In this chapter, we first review the fundamental concepts of machine learning such as feature assessment, unsupervised versus supervised learning and types of classification. Then, we point out the main issues of designing machine learning experiments and their performance evaluation. Finally, we introduce some supervised learning methods.

  18. LHC Report: machine development

    CERN Multimedia

    Rogelio Tomás García for the LHC team

    2015-01-01

    Machine development weeks are carefully planned in the LHC operation schedule to optimise and further study the performance of the machine. The first machine development session of Run 2 ended on Saturday, 25 July. Despite various hiccoughs, it allowed the operators to make great strides towards improving the long-term performance of the LHC.   The main goals of this first machine development (MD) week were to determine the minimum beam-spot size at the interaction points given existing optics and collimation constraints; to test new beam instrumentation; to evaluate the effectiveness of performing part of the beam-squeezing process during the energy ramp; and to explore the limits on the number of protons per bunch arising from the electromagnetic interactions with the accelerator environment and the other beam. Unfortunately, a series of events reduced the machine availability for studies to about 50%. The most critical issue was the recurrent trip of a sextupolar corrector circuit –...

  19. 'Mind the Gap!'

    DEFF Research Database (Denmark)

    Persson, Karl Gunnar

    This paper challenges the widely held view that sharply falling real transport costs closed the transatlantic gap in grain prices in the second half of the 19th century. Several new results emerge from an analysis of a new data set of weekly wheat prices and freight costs from New York to UK...... markets. Firstly, there was a decline in the transatlantic price gap but it was not sharp and the gap remained substantial. Secondly, the fall in the transatlantic price differential had more to do with improved market and marketing efficiency than with falling transport costs. Thirdly, spurious price...

  20. Machining a glass rod with a lathe-type electro-chemical discharge machine

    International Nuclear Information System (INIS)

    Furutani, Katsushi; Maeda, Hideaki

    2008-01-01

    This paper deals with the performance of electro-chemical discharge machining (ECDM) of a revolving glass rod. ECDM has been studied for machining insulating materials such as glass and ceramics. In conventional ECDM, an insulating workpiece is dipped in an electrolyte as a working fluid and a tool electrode is pressed on the surface with a small load. In the experiments, a workpiece was revolved to provide fresh working fluid into a gap between the tool electrode and the workpiece. A soda lime grass rod was machined with a thin tungsten rod in NaCl solution. The applied voltage was changed up to 40 V. The rotation speed was set to 0, 0.3, 3 and 30 min −1 . Discharge was observed over an applied voltage of 30 V. The width and depth of the machined grooves and the surface roughness of their bottom were increased with increase of the applied voltage. Although the depth of machining at 3 min −1 was the same as that at 30 min −1 , the width and roughness at 30 min −1 were smaller than those at 3 min −1 . Moreover, because the thickness of vaporization around the tool electrode was decreased with increase of the rotation speed, the width of the machined groove became smaller

  1. Advanced axial field D.C. motor development for electric passenger vehicle

    Science.gov (United States)

    Jones, W. J.

    1982-01-01

    A wound-field axial-flux dc motor was developed for an electric vehicle drive system. The motor is essentially an axial-flux version of the classical Gramme-ring winding motor, but the active conductors are recessed into slots cut into the two opposite faces of the laminated tape-wound core ring. Three motors were built and tested in the program. The second (functional) model was a six-pole machine which weighed 88.5 kg. It developed 16.9 km (33.0 hp), and a max speed of 4800 rpm. Full load efficiency was 92% and predicted SAE D-cycle efficiency was 88%. The last engineering) model was a 4-pole machine with compoles, allowing a weight reduction to 45 kg (100 lbs.) while addressing some manufacturability problems. The engineering model was rated at 13.2 kw (17.6 hp) at 3000 rpm, with a peak power of 19.8 km (26.4 hp) and a max speed of 7200 rpm. Initial test results on this motor showed poor commutation and efficiency; the program was terminated without resolution of these problems.

  2. Axial tomography in live cell laser microscopy

    Science.gov (United States)

    Richter, Verena; Bruns, Sarah; Bruns, Thomas; Weber, Petra; Wagner, Michael; Cremer, Christoph; Schneckenburger, Herbert

    2017-09-01

    Single cell microscopy in a three-dimensional (3-D) environment is reported. Cells are grown in an agarose culture gel, located within microcapillaries and observed from different sides after adaptation of an innovative device for sample rotation. Thus, z-stacks can be recorded by confocal microscopy in different directions and used for illustration in 3-D. This gives additional information, since cells or organelles that appear superimposed in one direction, may be well resolved in another one. The method is tested and validated with single cells expressing a membrane or a mitochondrially associated green fluorescent protein, or cells accumulating fluorescent quantum dots. In addition, axial tomography supports measurements of cellular uptake and distribution of the anticancer drug doxorubicin in the nucleus (2 to 6 h after incubation) or the cytoplasm (24 h). This paper discusses that upon cell rotation an enhanced optical resolution in lateral direction compared to axial direction can be utilized to obtain an improved effective 3-D resolution, which represents an important step toward super-resolution microscopy of living cells.

  3. Axial vessel widening in arborescent monocots.

    Science.gov (United States)

    Petit, Giai; DeClerck, Fabrice A J; Carrer, Marco; Anfodillo, Tommaso

    2014-02-01

    Dicotyledons have evolved a strategy to compensate for the increase in hydraulic resistance to water transport with height growth by widening xylem conduits downwards. In monocots, the accumulation of hydraulic resistance with height should be similar, but the absence of secondary growth represents a strong limitation for the maintenance of xylem hydraulic efficiency during ontogeny. The hydraulic architecture of monocots has been studied but it is unclear how monocots arrange their axial vascular structure during ontogeny to compensate for increases in height. We measured the vessel lumina and estimated the hydraulic diameter (Dh) at different heights along the stem of two arborescent monocots, Bactris gasipaes (Kunth) and Guadua angustifolia (Kunth). For the former, we also estimated the variation in Dh along the leaf rachis. Hydraulic diameter increased basally from the stem apex to the base with a scaling exponent (b) in the range of those reported for dicot trees (b = 0.22 in B. gasipaes; b = 0.31 and 0.23 in G. angustifolia). In B. gasipaes, vessels decrease in Dh from the stem's centre towards the periphery, an opposite pattern compared with dicot trees. Along the leaf rachis, a pattern of increasing Dh basally was also found (b = 0.13). The hydraulic design of the monocots studied revealed an axial pattern of xylem conduits similar to those evolved by dicots to compensate and minimize the negative effect of root-to-leaf length on hydrodynamic resistance to water flow.

  4. Anion-π Catalysts with Axial Chirality.

    Science.gov (United States)

    Wang, Chao; Matile, Stefan

    2017-09-04

    The idea of anion-π catalysis is to stabilize anionic transition states by anion-π interactions on aromatic surfaces. For asymmetric anion-π catalysis, π-acidic surfaces have been surrounded with stereogenic centers. This manuscript introduces the first anion-π catalysts that operate with axial chirality. Bifunctional catalysts with tertiary amine bases next to π-acidic naphthalenediimide planes are equipped with a bulky aromatic substituent in the imide position to produce separable atropisomers. The addition of malonic acid half thioesters to enolate acceptors is used for evaluation. In the presence of a chiral axis, the selective acceleration of the disfavored but relevant enolate addition was much better than with point chirality, and enantioselectivity could be observed for the first time for this reaction with small-molecule anion-π catalysts. Enantioselectivity increased with the π acidity of the π surface, whereas the addition of stereogenic centers around the aromatic plane did not cause further improvements. These results identify axial chirality of the active aromatic plane generated by atropisomerism as an attractive strategy for asymmetric anion-π catalysis. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Medullary sponge kidney on axial computed tomography

    International Nuclear Information System (INIS)

    Ginalski, J.-M.; Schnyder, Pierre; Portmann, Luc; Jaeger, Philippe

    1991-01-01

    To evaluate features of medullary sponge kidney (MSK) on computed tomography (CT), 4-mm-thick axial slices without intravenous contrast material were 1st made in 13 patients through 24 kidneys which showed images of MSK on excretory urograms. On CT, papillary calcifications were found in 11 kidneys. In 5 of these, the calcifications were not detectable on plain films. Some hyperdense papillae (attenuation value 55-70 Hounsfield units) without calcification were found in 4 other kidneys. 9 kidneys appeared normal. 10 of the 14 kidneys were reexamined by a 2nd series of 4-mm-thick axial slices, 5 min after intravenous injection of 50 ml of Urografin. Images suggesting possible ectasia of precaliceal tubules were found in only 4 kidneys. These images appear much less obvious and characteristic on CT than on excretory urogram and do nothing more than suggest the possibility of MSK. In conclusion, the sensitivity of CT in the detection of MSK is markedly lower than that of excretory urography. In the most florid cases of the disease, CT can only show images suggesting the possibility of MSK. On the other hand, CT appears much more sensitive than plain films and tomograms of excretory in the detection of papillary calcifications, the most frequent complication of MSK. (author). 13 refs.; 3 figs

  6. Canonical quantization of the generalized axial gauge

    International Nuclear Information System (INIS)

    Haller, K.

    1990-01-01

    The incompatibility of the constraint A 3 =0 with canonical commutation rules is discussed. A canonical formulation is given of QED and QCD in the axial gauge with n 1 =n 2 =0, n 3 =α and n 0 =β, where α and β are arbitrary real numbers. A Hilbert space is established for the perturbative theory, and a propagator is derived by obtaining an expression for the interaction picture gauge fields, and evaluating the vacuum expectation value of its time-ordered products in the perturbative vacuum. The propagator is expressed in terms of the parameter γ=α/β and is shown to reproduce the light cone gauge propagator when γ=1, and the temporal gauge propagator when γ=0, accommodating various prescriptions for the spurious propagator pole, including the Mandelstam-Leibbrandt and principal value prescriptions. When γ→∞, the generalized axial gauge propagator leads to an expression for the propagator in the A 3 =0 gauge, though in that case the order in which the integration over k 0 is performed, and the limit γ→∞ is taken, affects the resulting expression. Another Hilbert space is established, in which the constraints that include all interactions are implemented in a time independent fashion. It is pointed out that this Hilbert space, and the Hilbert space of the perturbative theory are unitarily equivalent in QED, but that they cannot be unitarily equivalent in QCD. Implications of this fact for the nonperturbative states of QCD are discussed. (orig.)

  7. The Modelling of Axially Translating Flexible Beams

    Science.gov (United States)

    Theodore, R. J.; Arakeri, J. H.; Ghosal, A.

    1996-04-01

    The axially translating flexible beam with a prismatic joint can be modelled by using the Euler-Bernoulli beam equation together with the convective terms. In general, the method of separation of variables cannot be applied to solve this partial differential equation. In this paper, a non-dimensional form of the Euler Bernoulli beam equation is presented, obtained by using the concept of group velocity, and also the conditions under which separation of variables and assumed modes method can be used. The use of clamped-mass boundary conditions leads to a time-dependent frequency equation for the translating flexible beam. A novel method is presented for solving this time dependent frequency equation by using a differential form of the frequency equation. The assume mode/Lagrangian formulation of dynamics is employed to derive closed form equations of motion. It is shown by using Lyapunov's first method that the dynamic responses of flexural modal variables become unstable during retraction of the flexible beam, which the dynamic response during extension of the beam is stable. Numerical simulation results are presented for the uniform axial motion induced transverse vibration for a typical flexible beam.

  8. Multi-axial response of idealized cermets

    International Nuclear Information System (INIS)

    Pickering, E.G.; Bele, E.; Deshpande, V.S.

    2016-01-01

    The yield response of two idealized cermets comprising mono and bi-disperse steel spheres in a Sn/Pb solder matrix has been investigated for a range of axisymmetric stress states. Proportional stress path experiments are reported, from which are extracted the initial yield surfaces and their evolution with increasing plastic strain. The initial yield strength is nearly independent of the hydrostatic pressure but the strain hardening rate increases with stress triaxiality up to a critical value. For higher triaxialities, the responses are independent of hydrostatic pressure. Multi-axial measurements along with X-ray tomography were used to demonstrate that the deformation of these idealized cermets occurs by two competing mechanisms: (i) a granular flow mechanism that operates at low levels of triaxiality, where volumetric dilation occurs under compressive stress states, and (ii) a plastically incompressible mechanism that operates at high stress triaxialities. A phenomenological viscoplastic constitutive model that incorporates both deformation mechanisms is presented. While such multi-axial measurements are difficult for commercial cermets with yield strengths on the order of a few GPa, the form of their constitutive relation is expected to be similar to that of the idealized cermets presented here.

  9. CIEEM Skills Gap Project

    OpenAIRE

    Bartlett, Deborah

    2017-01-01

    This paper describes the research conducted for the Chartered Institute for Ecology and Environmental Management to identify skills gaps within the profession. It involved surveys of professionals, conference workshops and an investigation into the views of employers regarding graduate recruitment.

  10. Wide-Gap Chalcopyrites

    CERN Document Server

    Siebentritt, Susanne

    2006-01-01

    Chalcopyrites, in particular those with a wide band gap, are fascinating materials in terms of their technological potential in the next generation of thin-film solar cells and in terms of their basic material properties. They exhibit uniquely low defect formation energies, leading to unusual doping and phase behavior and to extremely benign grain boundaries. This book collects articles on a number of those basic material properties of wide-gap chalcopyrites, comparing them to their low-gap cousins. They explore the doping of the materials, the electronic structure and the transport through interfaces and grain boundaries, the formation of the electric field in a solar cell, the mechanisms and suppression of recombination, the role of inhomogeneities, and the technological role of wide-gap chalcopyrites.

  11. Early age sealing of buffer-rock gap by artificial wetting to induce bentonite swelling

    International Nuclear Information System (INIS)

    Holt, Erika; Marjavaara, Pieti

    2012-01-01

    Document available in extended abstract form only. The aim of this work is to study the homogeneous and rapid swelling of bentonite in the gap between the buffer blocks and the rock wall of the Olkiluoto disposal facility by artificial wetting. The focus was on the construction period of the deposition hole and buffer, and thus only the very early ages of the first weeks. In practice it is desirable that the bentonite material has a volume increase sufficient enough to prevent rock scaling while lowering the risks of bentonite piping and erosion due to potential water flow. This initial study was done in a small-scale mock-up in laboratory conditions. The small-scale steel mock-up had dimensions of 39 cm in height by 36 cm in diameter and included 12 pressure sensors, two displacement transducers, thermal couples, and pore water pressure measurements. The radial and axial pressure development was typically measured over a two week period to assess the rate and magnitude of sealing. A steel confining lid was used for simulating overpressure, though in some cases a plexiglass lid was used to take video images of the gap sealing. The buffer blocks were produced by isostatic compression of 100 MPa. The material was MX-80 Wyoming bentonite having a water content of approximately 13% and a dry density of 1890 kg/m 3 . The testing samples were dry sawn and core drilled from the large block and machined to their final dimensions. These were typically 30 x 30 cm, either as a solid block or three disks of 10 cm height each. The diameter was sometimes varied to allow for a change of gap width between 25 to 50 mm The study included various scenarios, such as: eccentric aligned blocks with gap sizes of 5 and 45 mm, free upward swelling or confinement, different types of pellet and granular gap filling, addition of water at varying rates, and longer term test duration. The samples were typically disassembled after two weeks. At this ending point, material assessments were done

  12. Gender-Pay-Gap

    OpenAIRE

    Eicker, Jannis

    2017-01-01

    Der Gender-Pay-Gap ist eine statistische Kennzahl zur Messung der Ungleichheit zwischen Männern* und Frauen* beim Verdienst. Es gibt zwei Versionen: einen "unbereinigten" und einen "bereinigten". Der "unbereinigte" Gender-Pay-Gap berechnet den geschlechtsspezifischen Verdienstunterschied auf Basis der Bruttostundenlöhne aller Männer* und Frauen* der Grundgesamtheit. Beim "bereinigten" Wert hingegen werden je nach Studie verschiedene Faktoren wie Branche, Position und Berufserfahrung herausger...

  13. The Gender Pay Gap

    OpenAIRE

    Alan Manning

    2006-01-01

    Empirical research on gender pay gaps has traditionally focused on the role of gender-specific factors, particularly gender differences in qualifications and differences in the treatment of otherwise equally qualified male and female workers (i.e., labor market discrimination). This paper explores the determinants of the gender pay gap and argues for the importance of an additional factor, wage structure, the array of prices set for labor market skills and the rewards received for employment ...

  14. Machine Learning and Radiology

    Science.gov (United States)

    Wang, Shijun; Summers, Ronald M.

    2012-01-01

    In this paper, we give a short introduction to machine learning and survey its applications in radiology. We focused on six categories of applications in radiology: medical image segmentation, registration, computer aided detection and diagnosis, brain function or activity analysis and neurological disease diagnosis from fMR images, content-based image retrieval systems for CT or MRI images, and text analysis of radiology reports using natural language processing (NLP) and natural language understanding (NLU). This survey shows that machine learning plays a key role in many radiology applications. Machine learning identifies complex patterns automatically and helps radiologists make intelligent decisions on radiology data such as conventional radiographs, CT, MRI, and PET images and radiology reports. In many applications, the performance of machine learning-based automatic detection and diagnosis systems has shown to be comparable to that of a well-trained and experienced radiologist. Technology development in machine learning and radiology will benefit from each other in the long run. Key contributions and common characteristics of machine learning techniques in radiology are discussed. We also discuss the problem of translating machine learning applications to the radiology clinical setting, including advantages and potential barriers. PMID:22465077

  15. Machine learning and radiology.

    Science.gov (United States)

    Wang, Shijun; Summers, Ronald M

    2012-07-01

    In this paper, we give a short introduction to machine learning and survey its applications in radiology. We focused on six categories of applications in radiology: medical image segmentation, registration, computer aided detection and diagnosis, brain function or activity analysis and neurological disease diagnosis from fMR images, content-based image retrieval systems for CT or MRI images, and text analysis of radiology reports using natural language processing (NLP) and natural language understanding (NLU). This survey shows that machine learning plays a key role in many radiology applications. Machine learning identifies complex patterns automatically and helps radiologists make intelligent decisions on radiology data such as conventional radiographs, CT, MRI, and PET images and radiology reports. In many applications, the performance of machine learning-based automatic detection and diagnosis systems has shown to be comparable to that of a well-trained and experienced radiologist. Technology development in machine learning and radiology will benefit from each other in the long run. Key contributions and common characteristics of machine learning techniques in radiology are discussed. We also discuss the problem of translating machine learning applications to the radiology clinical setting, including advantages and potential barriers. Copyright © 2012. Published by Elsevier B.V.

  16. Comparison of femoropopliteal artery stents under axial and radial compression, axial tension, bending, and torsion deformations.

    Science.gov (United States)

    Maleckis, Kaspars; Deegan, Paul; Poulson, William; Sievers, Cole; Desyatova, Anastasia; MacTaggart, Jason; Kamenskiy, Alexey

    2017-11-01

    High failure rates of Peripheral Arterial Disease (PAD) stenting appear to be associated with the inability of certain stent designs to accommodate severe biomechanical environment of the femoropopliteal artery (FPA) that bends, twists, and axially compresses during limb flexion. Twelve Nitinol stents (Absolute Pro, Supera, Lifestent, Innova, Zilver, Smart Control, Smart Flex, EverFlex, Viabahn, Tigris, Misago, and Complete SE) were quasi-statically tested under bench-top axial and radial compression, axial tension, bending, and torsional deformations. Stents were compared in terms of force-strain behavior, stiffness, and geometrical shape under each deformation mode. Tigris was the least stiff stent under axial compression (6.6N/m axial stiffness) and bending (0.1N/m) deformations, while Smart Control was the stiffest (575.3N/m and 105.4N/m, respectively). Under radial compression Complete SE was the stiffest (892.8N/m), while Smart Control had the lowest radial stiffness (211.0N/m). Viabahn and Supera had the lowest and highest torsional stiffness (2.2μNm/° and 959.2μNm/°), respectively. None of the 12 PAD stents demonstrated superior characteristics under all deformation modes and many experienced global buckling and diameter pinching. Though it is yet to be determined which of these deformation modes might have greater clinical impact, results of the current analysis may help guide development of new stents with improved mechanical characteristics. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. DNA-based machines.

    Science.gov (United States)

    Wang, Fuan; Willner, Bilha; Willner, Itamar

    2014-01-01

    The base sequence in nucleic acids encodes substantial structural and functional information into the biopolymer. This encoded information provides the basis for the tailoring and assembly of DNA machines. A DNA machine is defined as a molecular device that exhibits the following fundamental features. (1) It performs a fuel-driven mechanical process that mimics macroscopic machines. (2) The mechanical process requires an energy input, "fuel." (3) The mechanical operation is accompanied by an energy consumption process that leads to "waste products." (4) The cyclic operation of the DNA devices, involves the use of "fuel" and "anti-fuel" ingredients. A variety of DNA-based machines are described, including the construction of "tweezers," "walkers," "robots," "cranes," "transporters," "springs," "gears," and interlocked cyclic DNA structures acting as reconfigurable catenanes, rotaxanes, and rotors. Different "fuels", such as nucleic acid strands, pH (H⁺/OH⁻), metal ions, and light, are used to trigger the mechanical functions of the DNA devices. The operation of the devices in solution and on surfaces is described, and a variety of optical, electrical, and photoelectrochemical methods to follow the operations of the DNA machines are presented. We further address the possible applications of DNA machines and the future perspectives of molecular DNA devices. These include the application of DNA machines as functional structures for the construction of logic gates and computing, for the programmed organization of metallic nanoparticle structures and the control of plasmonic properties, and for controlling chemical transformations by DNA machines. We further discuss the future applications of DNA machines for intracellular sensing, controlling intracellular metabolic pathways, and the use of the functional nanostructures for drug delivery and medical applications.

  18. Multi-axial load application and DIC measurement of advanced composite beam deformation behavior

    Directory of Open Access Journals (Sweden)

    Berggreen C.

    2010-06-01

    Full Text Available For the validation of a new beam element formulation, a wide set of experimental data consisting of deformation patterns obtained for a number of specially designed composite beam elements, have been obtained. The composite materials applied in the beams consist of glass-fiber reinforced plastic with specially designed layup configurations promoting advanced coupling behavior. Furthermore, the beams are designed with different cross-section shapes. The data obtained from the experiments are also used in order to improve the general understanding related to practical implementation of mechanisms of elastic couplings due to anisotropic properties of composite materials. The knowledge gained from these experiments is therefore essential in order to facilitate an implementation of passive control in future large wind turbine blades. A test setup based on a four-column MTS servo-hydraulic testing machine with a maximum capacity of 100 kN was developed, see Figure 1. The setup allows installing and testing beams of different cross-sections applying load cases such as axial extension, shear force bending, pure bending in two principal directions as well as pure torsion, see Figure 2. In order to apply multi-axial loading, a load application system consisting of three hydraulic actuators were mounted in two planes using multi-axial servo-hydraulic control. The actuator setup consists of the main actuator on the servo-hydraulic test machine working in the vertical axis (depicted on Figure 1 placed at the testing machine crosshead and used for application of vertical forces to the specimens. Two extra actuators are placed in a horizontal plane on the T-slot table of the test machine in different positions in order to apply loading at the tip of the specimen in various configurations. In order to precisely characterize the global as well as surface deformations of the beam specimens tested, a combination of different measurement systems were used during

  19. AIRGAP MAGNETIC INDUCTION DISTRIBUTION IN A COAXIALLY-LINEAR SYNCHRONOUS MOTOR WITH AXIAL AND RADIAL DIRECTION OF THE RUNNER PERMANENT MAGNETS MAGNETIZATION

    Directory of Open Access Journals (Sweden)

    Abbasian Mohsen

    2013-02-01

    Full Text Available Results of theoretical and experimental research on magnetic induction distribution in the air gap of a coaxially-linear synchronous motor with reciprocal motion within the pole pitch and axial and radial direction of the permanent magnets magnetization are presented.

  20. Fundamentals of machine design

    CERN Document Server

    Karaszewski, Waldemar

    2011-01-01

    A forum of researchers, educators and engineers involved in various aspects of Machine Design provided the inspiration for this collection of peer-reviewed papers. The resultant dissemination of the latest research results, and the exchange of views concerning the future research directions to be taken in this field will make the work of immense value to all those having an interest in the topics covered. The book reflects the cooperative efforts made in seeking out the best strategies for effecting improvements in the quality and the reliability of machines and machine parts and for extending

  1. Machine Learning for Hackers

    CERN Document Server

    Conway, Drew

    2012-01-01

    If you're an experienced programmer interested in crunching data, this book will get you started with machine learning-a toolkit of algorithms that enables computers to train themselves to automate useful tasks. Authors Drew Conway and John Myles White help you understand machine learning and statistics tools through a series of hands-on case studies, instead of a traditional math-heavy presentation. Each chapter focuses on a specific problem in machine learning, such as classification, prediction, optimization, and recommendation. Using the R programming language, you'll learn how to analyz

  2. Creativity in Machine Learning

    OpenAIRE

    Thoma, Martin

    2016-01-01

    Recent machine learning techniques can be modified to produce creative results. Those results did not exist before; it is not a trivial combination of the data which was fed into the machine learning system. The obtained results come in multiple forms: As images, as text and as audio. This paper gives a high level overview of how they are created and gives some examples. It is meant to be a summary of the current work and give people who are new to machine learning some starting points.

  3. Machine Tool Software

    Science.gov (United States)

    1988-01-01

    A NASA-developed software package has played a part in technical education of students who major in Mechanical Engineering Technology at William Rainey Harper College. Professor Hack has been using (APT) Automatically Programmed Tool Software since 1969 in his CAD/CAM Computer Aided Design and Manufacturing curriculum. Professor Hack teaches the use of APT programming languages for control of metal cutting machines. Machine tool instructions are geometry definitions written in APT Language to constitute a "part program." The part program is processed by the machine tool. CAD/CAM students go from writing a program to cutting steel in the course of a semester.

  4. The influence of the tangential velocity of inner rotating wall on axial velocity profile of flow through vertical annular pipe with rotating inner surface

    Directory of Open Access Journals (Sweden)

    Sharf Abdusalam M.

    2014-03-01

    Full Text Available In the oil and gas industries, understanding the behaviour of a flow through an annulus gap in a vertical position, whose outer wall is stationary whilst the inner wall rotates, is a significantly important issue in drilling wells. The main emphasis is placed on experimental (using an available rig and computational (employing CFD software investigations into the effects of the rotation speed of the inner pipe on the axial velocity profiles. The measured axial velocity profiles, in the cases of low axial flow, show that the axial velocity is influenced by the rotation speed of the inner pipe in the region of almost 33% of the annulus near the inner pipe, and influenced inversely in the rest of the annulus. The position of the maximum axial velocity is shifted from the centre to be nearer the inner pipe, by increasing the rotation speed. However, in the case of higher flow, as the rotation speed increases, the axial velocity is reduced and the position of the maximum axial velocity is skewed towards the centre of the annulus. There is a reduction of the swirl velocity corresponding to the rise of the volumetric flow rate.

  5. An improved torque density Modulated Pole Machine for low speed high torque applications

    DEFF Research Database (Denmark)

    Washington, J. G.; Atkinson, G. J.; Baker, N. J.

    2012-01-01

    This paper presents a new topology for three-phase Modulated Pole Machines. This new topology the “Combined Phase Modulated Pole Machine” is analysed and compared to the more traditional technology of three separate single phase units stacked axially with a separation between phases. Three......- dimensional Finite Element calculations are used to compare performance of the machines under the same conditions, it is shown that the new Combined Phase topology produces a greater torque whilst reducing the number of components required to assemble the machine and increasing its mechanical integrity....

  6. Gap length distributions by PEPR

    International Nuclear Information System (INIS)

    Warszawer, T.N.

    1980-01-01

    Conditions guaranteeing exponential gap length distributions are formulated and discussed. Exponential gap length distributions of bubble chamber tracks first obtained on a CRT device are presented. Distributions of resulting average gap lengths and their velocity dependence are discussed. (orig.)

  7. AIR GAP CONTROL SYSTEM FOR HYDROGENERATORS

    Directory of Open Access Journals (Sweden)

    I. O. Zaitsev

    2017-01-01

    Full Text Available In this paper, we report of the solving the actual problem of control the air gap in the hydrogenerators. The aim of the study was development of a computerized information-measuring system for measuring the air gap in the hydrogenator, which used two capacitive sensors with parallel coplanar electrodes, and the method of determining the shape of the envelope parameters hydrogenerator rotor poles relative to the center axis of rotation, using the measurement results of the air gap.In practical studies of the sensor circuit it has been shown that its use allows for the informative value of the sensor capacitance conversion function to obtain a high accuracy and resolution measurement with digital linearization of converting function of the sensor with use program utility. To determine the form deviations of the envelope line of the rotor pole from the ideal cylinder, which is one of the main structural defects of the technological errors as results the distortion of the shape of the air gap in the hydrogenator, when the machine was manufacture and assembly. It is proposed to describe the shape of the envelope to use a Fourier transform. Calculation of the coefficients of the Fourier series is performed using the method of least squares as the regression coefficients.Application of this method in processing the measuring data in a computerized information-measuring system the developed with the primary converter with coplanar parallel electrodes allowed attaining the high measurement accuracy and resolution informative in magnitude of the capacity.

  8. Comparison of Advanced Machine Learning Tools for Disruption Prediction and Disruption Studies

    Czech Academy of Sciences Publication Activity Database

    Odstrčil, Michal; Murari, A.; Mlynář, Jan

    2013-01-01

    Roč. 41, č. 7 (2013), s. 1751-1759 ISSN 0093-3813 R&D Projects: GA ČR GAP205/10/2055 Institutional support: RVO:61389021 Keywords : Learning Machines * Support Vector Machines * Neural Network * ASDEX Upgrade * JET * Disruption mitigation * Tokamaks * ITER Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 0.950, year: 2013

  9. Electrochemical machining of titanium alloys with the use of anodal activating pulses

    International Nuclear Information System (INIS)

    Davydov, A.D.; Klepikov, R.P.; Moroz, I.I.

    1980-01-01

    A comparative investigation of electrochemical machining of VT-6 titanium alloy by direct current and in different pulse mode is carried out taking into account the peculiarities of anodal behaviour of titanium alloys at high current desities. The mode of electrochemical machining of VT-6 alloy with activating pulses is chosen. It allows to conduct a process at lower voltages and small interelectrode gaps

  10. Chiral filter, axial charges and Gamow-Teller strengths

    International Nuclear Information System (INIS)

    Rho, M.

    1983-09-01

    The different ways that nuclear matter responds to the weak axial-vector current are interpreted in terms of modification of the ''vacuum'' in baryon-rich environments. The notion of ''chiral filter'' is introduced. Use of a ward identity is suggested. The Gamow-Teller quenching and the enhanced axial charge in O + O - transitions follow from this. I also discuss briefly possible relevance of the nucleon as a topological soliton configuration to the global property of nuclear axial response functions

  11. THE INFLUENCE OF LIMITING FACTORS ON ELECTRIC MACHINES ELECTROMAGNETIC POWER

    Directory of Open Access Journals (Sweden)

    Mr. Konstantin K. Kim

    2016-06-01

    Full Text Available The increase of electromechanical transducers single capacity is one of the main ways of their efficiency upgrading. The article discusses the impact of the main electromagnetic and me-chanical factors on the power, transmitted through the air gap of DC electric machines.

  12. Coordinate measuring machines

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This document is used in connection with three exercises of 2 hours duration as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The exercises concern three aspects of coordinate measuring: 1) Measuring and verification of tolerances on coordinate measuring machines, 2) Traceabilit...... and uncertainty during coordinate measurements, 3) Digitalisation and Reverse Engineering. This document contains a short description of each step in the exercise and schemes with room for taking notes of the results.......This document is used in connection with three exercises of 2 hours duration as a part of the course GEOMETRICAL METROLOGY AND MACHINE TESTING. The exercises concern three aspects of coordinate measuring: 1) Measuring and verification of tolerances on coordinate measuring machines, 2) Traceability...

  13. Machine Vision Handbook

    CERN Document Server

    2012-01-01

    The automation of visual inspection is becoming more and more important in modern industry as a consistent, reliable means of judging the quality of raw materials and manufactured goods . The Machine Vision Handbook  equips the reader with the practical details required to engineer integrated mechanical-optical-electronic-software systems. Machine vision is first set in the context of basic information on light, natural vision, colour sensing and optics. The physical apparatus required for mechanized image capture – lenses, cameras, scanners and light sources – are discussed followed by detailed treatment of various image-processing methods including an introduction to the QT image processing system. QT is unique to this book, and provides an example of a practical machine vision system along with extensive libraries of useful commands, functions and images which can be implemented by the reader. The main text of the book is completed by studies of a wide variety of applications of machine vision in insp...

  14. Enter the machine

    Science.gov (United States)

    Palittapongarnpim, Pantita; Sanders, Barry C.

    2018-05-01

    Quantum tomography infers quantum states from measurement data, but it becomes infeasible for large systems. Machine learning enables tomography of highly entangled many-body states and suggests a new powerful approach to this problem.

  15. Geometric inequalities for axially symmetric black holes

    International Nuclear Information System (INIS)

    Dain, Sergio

    2012-01-01

    A geometric inequality in general relativity relates quantities that have both a physical interpretation and a geometrical definition. It is well known that the parameters that characterize the Kerr-Newman black hole satisfy several important geometric inequalities. Remarkably enough, some of these inequalities also hold for dynamical black holes. This kind of inequalities play an important role in the characterization of the gravitational collapse; they are closely related with the cosmic censorship conjecture. Axially symmetric black holes are the natural candidates to study these inequalities because the quasi-local angular momentum is well defined for them. We review recent results in this subject and we also describe the main ideas behind the proofs. Finally, a list of relevant open problems is presented. (topical review)

  16. Collimated trans-axial tomographic scintillation camera

    International Nuclear Information System (INIS)

    1980-01-01

    The objects of this invention are first to reduce the time required to obtain statistically significant data in trans-axial tomographic radioisotope scanning using a scintillation camera. Secondly, to provide a scintillation camera system to increase the rate of acceptance of radioactive events to contribute to the positional information obtainable from a known radiation source without sacrificing spatial resolution. Thirdly to reduce the scanning time without loss of image clarity. The system described comprises a scintillation camera detector, means for moving this in orbit about a cranial-caudal axis relative to a patient and a collimator having septa defining apertures such that gamma rays perpendicular to the axis are admitted with high spatial resolution, parallel to the axis with low resolution. The septa may be made of strips of lead. Detailed descriptions are given. (U.K.)

  17. Collimated trans-axial tomographic scintillation camera

    International Nuclear Information System (INIS)

    1980-01-01

    The principal problem in trans-axial tomographic radioisotope scanning is the length of time required to obtain meaningful data. Patient movement and radioisotope migration during the scanning period can cause distortion of the image. The object of this invention is to reduce the scanning time without degrading the images obtained. A system is described in which a scintillation camera detector is moved to an orbit about the cranial-caudal axis relative to the patient. A collimator is used in which lead septa are arranged so as to admit gamma rays travelling perpendicular to this axis with high spatial resolution and those travelling in the direction of the axis with low spatial resolution, thus increasing the rate of acceptance of radioactive events to contribute to the positional information obtainable without sacrificing spatial resolution. (author)

  18. Axial tomographic system for radiation diagnoses

    International Nuclear Information System (INIS)

    Crowther, T.J.

    1977-01-01

    The axial tomographic scanner consists of a source of hard radiation passing a fan shaped beam through a plane layer of the body under examination, a detector, and driving systems for the sequential displacement and rotation of the radiation source and the detector. The diagnosis is made by means of a data processing system offering extensive time overlap capability of the individual system functions. The data sets from transmission or absorption are processed in three independent subsystems, i.e., the scanning system, the processing system and the display system. The systems are made up of well-known modules, e.g., Nova 1200 or Eclipse 5200. Hence, as a result of the independent design of the data system, raw data will not be lost in case of faults in some subsystem. (DG) [de

  19. Axial grazing collisions with insulator surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Gravielle, M.S. [Instituto de Astronomia y Fisica del Espacio (IAFE), Consejo Nacional de Investigaciones Cientificas y Tecnicas, Casilla de Correo 67, Sucursal 28, 1428 Buenos Aires (Argentina) and Departamento de Fisica, FCEN, Universidad de Buenos Aires (Argentina)]. E-mail: msilvia@iafe.uba.ar; Miraglia, J.E. [Instituto de Astronomia y Fisica del Espacio (IAFE), Consejo Nacional de Investigaciones Cientificas y Tecnicas, Casilla de Correo 67, Sucursal 28, 1428 Buenos Aires (Argentina); Departamento de Fisica, FCEN, Universidad de Buenos Aires (Argentina)

    2007-05-15

    Electron capture and emission processes from insulator surfaces produced by grazing impact of fast ions are investigated under axial incidence conditions. For crystal surfaces we develop a model based on distorted wave methods, which allows us to express the coherent transition amplitude along the projectile path as a sum of atomic amplitudes, each one associated with a different lattice site. The method is applied to 100 keV protons colliding with LiF surfaces. For electron transitions from a given initial crystal state, the probabilities display strong interference effects as a function of the crystal orientation. But the interference patterns disappear when these partial probabilities are added to derive the total probability from the surface band.

  20. Axial grazing collisions with insulator surfaces

    International Nuclear Information System (INIS)

    Gravielle, M.S.; Miraglia, J.E.

    2007-01-01

    Electron capture and emission processes from insulator surfaces produced by grazing impact of fast ions are investigated under axial incidence conditions. For crystal surfaces we develop a model based on distorted wave methods, which allows us to express the coherent transition amplitude along the projectile path as a sum of atomic amplitudes, each one associated with a different lattice site. The method is applied to 100 keV protons colliding with LiF surfaces. For electron transitions from a given initial crystal state, the probabilities display strong interference effects as a function of the crystal orientation. But the interference patterns disappear when these partial probabilities are added to derive the total probability from the surface band

  1. Axial nonimaging characteristics of imaging lenses: discussion.

    Science.gov (United States)

    Siew, Ronian

    2016-05-01

    At observation planes away from the image plane, an imaging lens is a nonimaging optic. We examine the variation of axial irradiance with distance in image space and highlight the following little-known observation for discussion: On a per-unit-area basis, the position of the highest concentration in image space is generally not at the focal plane. This characteristic is contrary to common experience, and it offers an additional degree of freedom for the design of detection systems. Additionally, it would also apply to lenses with negative refractive index. The position of peak concentration and its irradiance is dependent upon the location and irradiance of the image. As such, this discussion also includes a close examination of expressions for image irradiance and explains how they are related to irradiance calculations beyond the image plane. This study is restricted to rotationally symmetric refractive imaging systems with incoherent extended Lambertian sources.

  2. Image reconstruction. Application to transverse axial tomography

    International Nuclear Information System (INIS)

    Aubry, Florent.

    1977-09-01

    A method of computerized tridimensional image reconstruction from their projection, especially in the computerized transverse axial tomography is suggested. First, the different techniques actually developped and presented in the literature are analyzed. Then, the equipment used is briefly described. The reconstruction algorithm developped is presented. This algorithm is based on the convolution method, well adapted to the real conditions of exploitation. It is an extension of SHEPP and LOGAN's algorithm. A correction of the self absorption and of the detector's response is proposed. Finally, the first results obtained which are satisfactory are given. The simplicity of the method which does not need a too long computation time makes possible the implementation of the algorithm on a mini-computer [fr

  3. Composite Axial Flow Propulsor for Small Aircraft

    Directory of Open Access Journals (Sweden)

    R. Poul

    2005-01-01

    Full Text Available This work focuses on the design of an axial flow ducted fan driven by a reciprocating engine. The solution minimizes the turbulization of the flow around the aircraft. The fan has a rotor - stator configuration. Due to the need for low weight of the fan, a carbon/epoxy composite material was chosen for the blades and the driving shaft.The fan is designed for optimal isentropic efficiency and free vortex flow. A stress analysis of the rotor blade was performed using the Finite Element  Method. The skin of the blade is calculated as a laminate and the foam core as a solid. A static and dynamic analysis were made. The RTM technology is compared with other technologies and is described in detail. 

  4. Introduction to AC machine design

    CERN Document Server

    Lipo, Thomas A

    2018-01-01

    AC electrical machine design is a key skill set for developing competitive electric motors and generators for applications in industry, aerospace, and defense. This book presents a thorough treatment of AC machine design, starting from basic electromagnetic principles and continuing through the various design aspects of an induction machine. Introduction to AC Machine Design includes one chapter each on the design of permanent magnet machines, synchronous machines, and thermal design. It also offers a basic treatment of the use of finite elements to compute the magnetic field within a machine without interfering with the initial comprehension of the core subject matter. Based on the author's notes, as well as after years of classroom instruction, Introduction to AC Machine Design: * Brings to light more advanced principles of machine design--not just the basic principles of AC and DC machine behavior * Introduces electrical machine design to neophytes while also being a resource for experienced designers * ...

  5. Estimation of ocular volume from axial length.

    Science.gov (United States)

    Nagra, Manbir; Gilmartin, Bernard; Logan, Nicola S

    2014-12-01

    To determine which biometric parameters provide optimum predictive power for ocular volume. Sixty-seven adult subjects were scanned with a Siemens 3-T MRI scanner. Mean spherical error (MSE) (D) was measured with a Shin-Nippon autorefractor and a Zeiss IOLMaster used to measure (mm) axial length (AL), anterior chamber depth (ACD) and corneal radius (CR). Total ocular volume (TOV) was calculated from T2-weighted MRIs (voxel size 1.0 mm(3)) using an automatic voxel counting and shading algorithm. Each MR slice was subsequently edited manually in the axial, sagittal and coronal plane, the latter enabling location of the posterior pole of the crystalline lens and partitioning of TOV into anterior (AV) and posterior volume (PV) regions. Mean values (±SD) for MSE (D), AL (mm), ACD (mm) and CR (mm) were -2.62±3.83, 24.51±1.47, 3.55±0.34 and 7.75±0.28, respectively. Mean values (±SD) for TOV, AV and PV (mm(3)) were 8168.21±1141.86, 1099.40±139.24 and 7068.82±1134.05, respectively. TOV showed significant correlation with MSE, AL, PV (all p<0.001), CR (p=0.043) and ACD (p=0.024). Bar CR, the correlations were shown to be wholly attributable to variation in PV. Multiple linear regression indicated that the combination of AL and CR provided optimum R(2) values of 79.4% for TOV. Clinically useful estimations of ocular volume can be obtained from measurement of AL and CR. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  6. Axially symmetric Lorentzian wormholes in general relativity

    International Nuclear Information System (INIS)

    Schein, F.

    1997-11-01

    The field equations of Einstein's theory of general relativity, being local, do not fix the global structure of space-time. They admit topologically non-trivial solutions, including spatially closed universes and the amazing possibility of shortcuts for travel between distant regions in space and time - so-called Lorentzian wormholes. The aim of this thesis is to (mathematically) construct space-times which contain traversal wormholes connecting arbitrary distant regions of an asymptotically flat or asymptotically de Sitter universe. Since the wormhole mouths appear as two separate masses in the exterior space, space-time can at best be axially symmetric. We eliminate the non-staticity caused by the gravitational attraction of the mouths by anchoring them by strings held at infinity or, alternatively, by electric repulsion. The space-times are obtained by surgically grafting together well-known solutions of Einstein's equations along timelike hypersurfaces. This surgery naturally concentrates a non-zero stress-energy tensor on the boundary between the two space-times which can be investigated by using the standard thin shell formalism. It turns out that, when using charged black holes, the provided constructions are possible without violation of any of the energy conditions. In general, observers living in the axially symmetric, asymptotically flat (respectively asymptotically de Sitter) region axe able to send causal signals through the topologically non-trivial region. However, the wormhole space-times contain closed timelike curves. Because of this explicit violation of global hyperbolicity these models do not serve as counterexamples to known topological censorship theorems. (author)

  7. Energy Dissipation in Sandwich Structures During Axial Compression

    DEFF Research Database (Denmark)

    Urban, Jesper

    2002-01-01

    The purpose of this paper is to investigate the energy dissipation in sandwich structures during axial crushing. Axial crushing tests on six sandwich elements are described. The sandwich elements consist of a polyurethane core and E-glass/Polyester skin. The elements compare to full-scale structu......The purpose of this paper is to investigate the energy dissipation in sandwich structures during axial crushing. Axial crushing tests on six sandwich elements are described. The sandwich elements consist of a polyurethane core and E-glass/Polyester skin. The elements compare to full...

  8. Improved axial position detection in optical tweezers measurements

    DEFF Research Database (Denmark)

    Dreyer, Jakob Kisbye; Berg-Sørensen, Kirstine; Oddershede, Lene

    2004-01-01

    We investigate the axial position detection of a trapped microsphere in an optical trap by using a quadrant photodiode. By replacing the photodiode with a CCD camera, we obtain detailed information on the light scattered by the microsphere. The correlation of the interference pattern with the axial...... position displays complex behavior with regions of positive and negative interference. By analyzing the scattered light intensity as a function of the axial position of the trapped sphere, we propose a simple method to increase the sensitivity and control the linear range of axial position detection....

  9. Metalworking and machining fluids

    Science.gov (United States)

    Erdemir, Ali; Sykora, Frank; Dorbeck, Mark

    2010-10-12

    Improved boron-based metal working and machining fluids. Boric acid and boron-based additives that, when mixed with certain carrier fluids, such as water, cellulose and/or cellulose derivatives, polyhydric alcohol, polyalkylene glycol, polyvinyl alcohol, starch, dextrin, in solid and/or solvated forms result in improved metalworking and machining of metallic work pieces. Fluids manufactured with boric acid or boron-based additives effectively reduce friction, prevent galling and severe wear problems on cutting and forming tools.

  10. Superconducting machines. Chapter 4

    International Nuclear Information System (INIS)

    Appleton, A.D.

    1977-01-01

    A brief account is given of the principles of superconductivity and superconductors. The properties of Nb-Ti superconductors and the method of flux stabilization are described. The basic features of superconducting d.c. machines are illustrated by the use of these machines for ship propulsion, steel-mill drives, industrial drives, aluminium production, and other d.c. power supplies. Superconducting a.c. generators and their design parameters are discussed. (U.K.)

  11. Quantum Machine Learning

    OpenAIRE

    Romero García, Cristian

    2017-01-01

    [EN] In a world in which accessible information grows exponentially, the selection of the appropriate information turns out to be an extremely relevant problem. In this context, the idea of Machine Learning (ML), a subfield of Artificial Intelligence, emerged to face problems in data mining, pattern recognition, automatic prediction, among others. Quantum Machine Learning is an interdisciplinary research area combining quantum mechanics with methods of ML, in which quantum properties allow fo...

  12. Human-machine interactions

    Science.gov (United States)

    Forsythe, J Chris [Sandia Park, NM; Xavier, Patrick G [Albuquerque, NM; Abbott, Robert G [Albuquerque, NM; Brannon, Nathan G [Albuquerque, NM; Bernard, Michael L [Tijeras, NM; Speed, Ann E [Albuquerque, NM

    2009-04-28

    Digital technology utilizing a cognitive model based on human naturalistic decision-making processes, including pattern recognition and episodic memory, can reduce the dependency of human-machine interactions on the abilities of a human user and can enable a machine to more closely emulate human-like responses. Such a cognitive model can enable digital technology to use cognitive capacities fundamental to human-like communication and cooperation to interact with humans.

  13. Some relations between quantum Turing machines and Turing machines

    OpenAIRE

    Sicard, Andrés; Vélez, Mario

    1999-01-01

    For quantum Turing machines we present three elements: Its components, its time evolution operator and its local transition function. The components are related with the components of deterministic Turing machines, the time evolution operator is related with the evolution of reversible Turing machines and the local transition function is related with the transition function of probabilistic and reversible Turing machines.

  14. SRTC - Gap Analysis Table

    International Nuclear Information System (INIS)

    M.L. Johnson

    2005-01-01

    The purpose of this document is to review the existing SRTC design against the ''Nuclear Safety Design Bases for License Application'' (NSDB) [Ref. 10] requirements and to identify codes and standards and supplemental requirements to meet these requirements. If these codes and standards and supplemental requirements can not fully meet these safety requirements then a ''gap'' is identified. These gaps will be identified here and addressed using the ''Site Rail Transfer Cart (SRTC) Design Development Plan'' [Ref. 14]. The codes and standards, supplemental requirements, and design development requirements are provided in the SRTC and associated rails gap analysis table in Appendix A. Because SRTCs are credited with performing functions important to safety (ITS) in the NSDB [Ref. 10], design basis requirements are applicable to ensure equipment is available and performs required safety functions when needed. The gap analysis table is used to identify design objectives and provide a means to satisfy safety requirements. To ensure that the SRTC and rail design perform required safety Functions and meet performance criteria, this portion of the gap analysis table supplies codes and standards sections and the supplemental requirements and identifies design development requirements, if needed

  15. Reactor refueling machine simulator

    International Nuclear Information System (INIS)

    Rohosky, T.L.; Swidwa, K.J.

    1987-01-01

    This patent describes in combination: a nuclear reactor; a refueling machine having a bridge, trolley and hoist each driven by a separate motor having feedback means for generating a feedback signal indicative of movement thereof. The motors are operable to position the refueling machine over the nuclear reactor for refueling the same. The refueling machine also has a removable control console including means for selectively generating separate motor signals for operating the bridge, trolley and hoist motors and for processing the feedback signals to generate an indication of the positions thereof, separate output leads connecting each of the motor signals to the respective refueling machine motor, and separate input leads for connecting each of the feedback means to the console; and a portable simulator unit comprising: a single simulator motor; a single simulator feedback signal generator connected to the simulator motor for generating a simulator feedback signal in response to operation of the simulator motor; means for selectively connecting the output leads of the console to the simulator unit in place of the refueling machine motors, and for connecting the console input leads to the simulator unit in place of the refueling machine motor feedback means; and means for driving the single simulator motor in response to any of the bridge, trolley or hoist motor signals generated by the console and means for applying the simulator feedback signal to the console input lead associated with the motor signal being generated by the control console

  16. The Three-Dimensional Velocity Distribution of Wide Gap Taylor-Couette Flow Modelled by CFD

    Directory of Open Access Journals (Sweden)

    David Shina Adebayo

    2016-01-01

    Full Text Available A numerical investigation is conducted for the flow between two concentric cylinders with a wide gap, relevant to bearing chamber applications. This wide gap configuration has received comparatively less attention than narrow gap journal bearing type geometries. The flow in the gap between an inner rotating cylinder and an outer stationary cylinder has been modelled as an incompressible flow using an implicit finite volume RANS scheme with the realisable k-ε model. The model flow is above the critical Taylor number at which axisymmetric counterrotating Taylor vortices are formed. The tangential velocity profiles at all axial locations are different from typical journal bearing applications, where the velocity profiles are quasilinear. The predicted results led to two significant findings of impact in rotating machinery operations. Firstly, the axial variation of the tangential velocity gradient induces an axially varying shear stress, resulting in local bands of enhanced work input to the working fluid. This is likely to cause unwanted heat transfer on the surface in high torque turbomachinery applications. Secondly, the radial inflow at the axial end-wall boundaries is likely to promote the transport of debris to the junction between the end-collar and the rotating cylinder, causing the build-up of fouling in the seal.

  17. Manufacture of mirrors by NC machining of EEM

    International Nuclear Information System (INIS)

    Hongo, Toshio; Azuma, Yasuo; Kato, Haruo; Hoshino, Hideo

    1981-01-01

    In the X-ray optical system for the photon factory facility being constructed now in the National Laboratory for High Energy Physics, total reflection mirrors occupy important position. The shapes of mirrors are both plane and curved surface, and the sizes are various. Especially concerning hard X-ray, the required accuracy of the shapes and surface roughness is high. Thereupon mirrors were machined by elastic emission machining (EEM) developed by Mori et al. of Osaka University, and the flatness and surface roughness were examined. The materials machined were Pyrex and copper, the mirror finish of which is difficult. The results are reported. In this machining method, the liquid in which very fine powder is uniformly dispersed and suspended in water was used. By approaching a rotating urethane ball to a work surface, the gap of about 1 μm was formed between them utilizing fluid bearing-like flow arising there. The machining was carried out by colliding the fine particles in suspension to a minute region of the work surface. In order to obtain an arbitrary curved surface, the numerical control according to the variable controling the amount of machining was made. In the case of glasses, the amount of machining was able to be controlled to about 0.01 μm. As for polycrystalline copper, the machining was difficult, and the suitable conditions must be sought hereafter. (Kako, I.)

  18. Retention system and method for the blades of a rotary machine

    Science.gov (United States)

    Pedersen, Poul D.; Glynn, Christopher C.; Walker, Roger C.

    2002-01-01

    A retention system and method for the blades of a rotary machine for preventing forward or aft axial movement of the rotor blades includes a circumferential hub slot formed about a circumference of the machine hub. The rotor blades have machined therein a blade retention slot which is aligned with the circumferential hub slot when the blades are received in correspondingly shaped openings in the hub. At least one ring segment is secured in the blade retention slots and the circumferential hub slot to retain the blades from axial movement. A key assembly is used to secure the ring segments in the aligned slots via a hook portion receiving the ring segments and a threaded portion that is driven radially outwardly by a nut. A cap may be provided to provide a redundant back-up load path for the centrifugal loads on the key. Alternatively, the key assembly may be formed in the blade dovetail.

  19. Design and analysis of a toroidal tester for the measurement of core losses under axial compressive stress

    Science.gov (United States)

    Alatawneh, Natheer; Rahman, Tanvir; Lowther, David A.; Chromik, Richard

    2017-06-01

    Electric machine cores are subjected to mechanical stresses due to manufacturing processes. These stresses include radial, circumferential and axial components that may have significant influences on the magnetic properties of the electrical steel and hence, on the output and efficiencies of electrical machines. Previously, most studies of iron losses due to mechanical stress have considered only radial and circumferential components. In this work, an improved toroidal tester has been designed and developed to measure the core losses and the magnetic properties of electrical steel under a compressive axial stress. The shape of the toroidal ring has been verified using 3D stress analysis. Also, 3D electromagnetic simulations show a uniform flux density distribution in the specimen with a variation of 0.03 T and a maximum average induction level of 1.5 T. The developed design has been prototyped, and measurements were carried out using a steel sample of grade 35WW300. Measurements show that applying small mechanical stresses normal to the sample thickness rises the delivered core losses, then the losses decrease continuously as the stress increases. However, the drop in core losses at high stresses does not go lower than the free-stress condition. Physical explanations for the observed trend of core losses as a function of stress are provided based on core loss separation to the hysteresis and eddy current loss components. The experimental results show that the effect of axial compressive stress on magnetic properties of electrical steel at high level of inductions becomes less pronounced.

  20. Financial signal processing and machine learning

    CERN Document Server

    Kulkarni,Sanjeev R; Dmitry M. Malioutov

    2016-01-01

    The modern financial industry has been required to deal with large and diverse portfolios in a variety of asset classes often with limited market data available. Financial Signal Processing and Machine Learning unifies a number of recent advances made in signal processing and machine learning for the design and management of investment portfolios and financial engineering. This book bridges the gap between these disciplines, offering the latest information on key topics including characterizing statistical dependence and correlation in high dimensions, constructing effective and robust risk measures, and their use in portfolio optimization and rebalancing. The book focuses on signal processing approaches to model return, momentum, and mean reversion, addressing theoretical and implementation aspects. It highlights the connections between portfolio theory, sparse learning and compressed sensing, sparse eigen-portfolios, robust optimization, non-Gaussian data-driven risk measures, graphical models, causal analy...

  1. Dual-detection confocal fluorescence microscopy: fluorescence axial imaging without axial scanning.

    Science.gov (United States)

    Lee, Dong-Ryoung; Kim, Young-Duk; Gweon, Dae-Gab; Yoo, Hongki

    2013-07-29

    We propose a new method for high-speed, three-dimensional (3-D) fluorescence imaging, which we refer to as dual-detection confocal fluorescence microscopy (DDCFM). In contrast to conventional beam-scanning confocal fluorescence microscopy, where the focal spot must be scanned either optically or mechanically over a sample volume to reconstruct a 3-D image, DDCFM can obtain the depth of a fluorescent emitter without depth scanning. DDCFM comprises two photodetectors, each with a pinhole of different size, in the confocal detection system. Axial information on fluorescent emitters can be measured by the axial response curve through the ratio of intensity signals. DDCFM can rapidly acquire a 3-D fluorescent image from a single two-dimensional scan with less phototoxicity and photobleaching than confocal fluorescence microscopy because no mechanical depth scans are needed. We demonstrated the feasibility of the proposed method by phantom studies.

  2. [A new machinability test machine and the machinability of composite resins for core built-up].

    Science.gov (United States)

    Iwasaki, N

    2001-06-01

    A new machinability test machine especially for dental materials was contrived. The purpose of this study was to evaluate the effects of grinding conditions on machinability of core built-up resins using this machine, and to confirm the relationship between machinability and other properties of composite resins. The experimental machinability test machine consisted of a dental air-turbine handpiece, a control weight unit, a driving unit of the stage fixing the test specimen, and so on. The machinability was evaluated as the change in volume after grinding using a diamond point. Five kinds of core built-up resins and human teeth were used in this study. The machinabilities of these composite resins increased with an increasing load during grinding, and decreased with repeated grinding. There was no obvious correlation between the machinability and Vickers' hardness; however, a negative correlation was observed between machinability and scratch width.

  3. Simulation of a 3D unsteady flow in an axial turbine stage

    Directory of Open Access Journals (Sweden)

    Straka Petr

    2012-04-01

    Full Text Available The contribution deals with a numerical simulation of an unsteady flow in an axial turbine stage. The solution is performed using an in-house numerical code developed in the Aeronautical and Test Institute, Plc. in Prague. The numerical code is based on a finite volume discretization of governing equations (Favre averaged Navier-Stokes equations and a two-equations turbulence model. The temporal integration is based on the implicit second-order backward Euler formula, which is realized through the iteration process in dual time. The proposed numerical method is used for solution of the 3D, unsteady, viscous turbulent flow of a perfect gas in the axial turbine stage. The flow path consists of an input nozzle, stator blade-wheel, rotor blade-wheel, a shroud-seal gap and a diffuser. Attention is paid to the influence of a secondary flow structures, such as generated vortices and flow in shroud-seal gap.

  4. The longevity gender gap

    DEFF Research Database (Denmark)

    Aviv, Abraham; Shay, Jerry; Christensen, Kaare

    2005-01-01

    In this Perspective, we focus on the greater longevity of women as compared with men. We propose that, like aging itself, the longevity gender gap is exceedingly complex and argue that it may arise from sex-related hormonal differences and from somatic cell selection that favors cells more...... resistant to the ravages of time. We discuss the interplay of these factors with telomere biology and oxidative stress and suggest that an explanation for the longevity gender gap may arise from a better understanding of the differences in telomere dynamics between men and women....

  5. The Knife Machine. Module 15.

    Science.gov (United States)

    South Carolina State Dept. of Education, Columbia. Office of Vocational Education.

    This module on the knife machine, one in a series dealing with industrial sewing machines, their attachments, and operation, covers one topic: performing special operations on the knife machine (a single needle or multi-needle machine which sews and cuts at the same time). These components are provided: an introduction, directions, an objective,…

  6. The Buttonhole Machine. Module 13.

    Science.gov (United States)

    South Carolina State Dept. of Education, Columbia. Office of Vocational Education.

    This module on the bottonhole machine, one in a series dealing with industrial sewing machines, their attachments, and operation, covers two topics: performing special operations on the buttonhole machine (parts and purpose) and performing special operations on the buttonhole machine (gauged buttonholes). For each topic these components are…

  7. Comparison of Flux Regulation Ability of the Hybrid Excitation Doubly Salient Machines

    DEFF Research Database (Denmark)

    Chen, ZhiHui; Wang, Bo; Chen, Zhe

    2014-01-01

    A hybrid excitation doubly salient machine (DSM) (HEDSM) can adjust the air gap flux with the limited field exciting ampere-turns. There are a few studied structures with different air gap flux regulation abilities. In this paper, several HEDSMs with different structures are analyzed by using an ...

  8. Machining of Metal Matrix Composites

    CERN Document Server

    2012-01-01

    Machining of Metal Matrix Composites provides the fundamentals and recent advances in the study of machining of metal matrix composites (MMCs). Each chapter is written by an international expert in this important field of research. Machining of Metal Matrix Composites gives the reader information on machining of MMCs with a special emphasis on aluminium matrix composites. Chapter 1 provides the mechanics and modelling of chip formation for traditional machining processes. Chapter 2 is dedicated to surface integrity when machining MMCs. Chapter 3 describes the machinability aspects of MMCs. Chapter 4 contains information on traditional machining processes and Chapter 5 is dedicated to the grinding of MMCs. Chapter 6 describes the dry cutting of MMCs with SiC particulate reinforcement. Finally, Chapter 7 is dedicated to computational methods and optimization in the machining of MMCs. Machining of Metal Matrix Composites can serve as a useful reference for academics, manufacturing and materials researchers, manu...

  9. Fuel charging machine

    International Nuclear Information System (INIS)

    Uchikawa, Sadao.

    1978-01-01

    Purpose: To enable continuous fuel discharging and charging steps in a bwr type reactor by effecting positioning only for once by providing a plurality of fuel assembly grippers and their drives co-axially on a rotatable surface. Constitution: A plurality of fuel assembly grippers and their drives are provided co-axially on a rotatable surface. For example, a gripper A, a drive B, a gripper C and a drive D are arranged co-axially in symmetric positions on a disk rotated on rails by wheels and rotational drives. A new fuel in a fuel pool is gripped by the gripper A and transported above the reactor core. Then, the disk is positioned so that the gripper C can grip the spent fuel in the core, and the fuel to be discharged is gripped and raised by the gripper C. Then the disk is rotated by 180 0 and the new fuel in the gripper A is charged into the position from which the old fuel has been discharged and, finally, the discharged fuel is sent to the fuel pool for storage. (Seki, T.)

  10. Gap eigenmode of radially localized helicon waves in a periodic structure

    International Nuclear Information System (INIS)

    Chang, L; Hole, M J; Breizman, B N

    2013-01-01

    An ElectroMagnetic Solver (Chen et al 2006 Phys. Plasmas 13 123507) is employed to model a spectral gap and a gap eigenmode in a periodic structure in the whistler frequency range. A radially localized helicon mode (Breizman and Arefiev 2000 Phys. Rev. Lett. 84 3863) is considered. We demonstrate that the computed gap frequency and gap width agree well with a theoretical analysis, and find a discrete eigenmode inside the gap by introducing a defect to the system's periodicity. The axial wavelength of the gap eigenmode is close to twice the system's periodicity, which is consistent with Bragg's law. Such an eigenmode could be excited by energetic electrons, similar to the excitation of toroidal Alfvén eigenmodes by energetic ions in tokamaks. Experimental identification of this mode is conceivable on the large plasma device (Gekelman et al 1991 Rev. Sci. Instrum. 62 2875). (paper)

  11. Virtual Machine in Automation Projects

    OpenAIRE

    Xing, Xiaoyuan

    2010-01-01

    Virtual machine, as an engineering tool, has recently been introduced into automation projects in Tetra Pak Processing System AB. The goal of this paper is to examine how to better utilize virtual machine for the automation projects. This paper designs different project scenarios using virtual machine. It analyzes installability, performance and stability of virtual machine from the test results. Technical solutions concerning virtual machine are discussed such as the conversion with physical...

  12. Non-conventional electrical machines

    CERN Document Server

    Rezzoug, Abderrezak

    2013-01-01

    The developments of electrical machines are due to the convergence of material progress, improved calculation tools, and new feeding sources. Among the many recent machines, the authors have chosen, in this first book, to relate the progress in slow speed machines, high speed machines, and superconducting machines. The first part of the book is dedicated to materials and an overview of magnetism, mechanic, and heat transfer.

  13. Estimating Gender Wage Gaps

    Science.gov (United States)

    McDonald, Judith A.; Thornton, Robert J.

    2011-01-01

    Course research projects that use easy-to-access real-world data and that generate findings with which undergraduate students can readily identify are hard to find. The authors describe a project that requires students to estimate the current female-male earnings gap for new college graduates. The project also enables students to see to what…

  14. Bifunctional organocatalysts for the asymmetric synthesis of axially chiral benzamides

    Directory of Open Access Journals (Sweden)

    Ryota Miyaji

    2017-08-01

    Full Text Available Bifunctional organocatalysts bearing amino and urea functional groups in a chiral molecular skeleton were applied to the enantioselective synthesis of axially chiral benzamides via aromatic electrophilic bromination. The results demonstrate the versatility of bifunctional organocatalysts for the enantioselective construction of axially chiral compounds. Moderate to good enantioselectivities were afforded with a range of benzamide substrates. Mechanistic investigations were also carried out.

  15. Test Setup for Axially Loaded Piles in Sand

    DEFF Research Database (Denmark)

    Thomassen, Kristina

    The test setup for testing axially static and cyclic loaded piles in sand is described in the following. The purpose for the tests is to examine the tensile capacity of axially loaded piles in dense fully saturated sand. The pile dimensions are chosen to resemble full scale dimension of piles used...... in offshore pile foundations today....

  16. Characterisation of plasmas produced by the "Torche a Injection Axiale"

    NARCIS (Netherlands)

    Jonkers, J.; Selen, L.J.M.; Mullen, van der J.J.A.M.; Regt, de J.M.; Timmermans, E.A.H.; Schram, D.C.

    1996-01-01

    Summary form only given. The Torche a Injection Axiale (TIA), i.e. torch with axial gas injection, was developed by the group of Moisan in 1993. We report on the investigations on two different kind of plasmas created by the TIA: one with helium and the other with argon as main gas. Using absolute

  17. Equation of motion for the axial gravitational superfield

    International Nuclear Information System (INIS)

    Ogievetsky, V.; Sokatchev, E.

    1980-01-01

    Transformation properties of the axial supergravitational field variants are investigated. The equation of motion for the axial gravitational superfield is derived by direct variation of the N = 1 supergravity action. The left-hand side of this equation is a component of the torsion tensor, and the right-hand side is the supercurrent. The question about the cosmological term in supergravity is discussed

  18. Original paper Cytokine profiles in axial spondyloarthritis

    Directory of Open Access Journals (Sweden)

    Marta Madej

    2015-04-01

    Full Text Available Objectives: Current studies concentrate on the cytokine network and its role in the pathogenesis of spondyloarthritis (SpA. In this study, we analyzed whether the serum cytokine profile (interleukins: IL-10, IL-11, IL-12, IL-15, IL-17, IL-23 and IL-33 correlates with demographic data, clinical manifestations, disease activity and treatment outcome in a group of patients with axial spondyloarthritis. Material and methods: Forty-nine patients with an established diagnosis of axial spondyloarthritis (aSpA and 19 healthy volunteers as controls were enrolled in the study. Clinical evaluation included patient’s medical history, 44 joint count, back pain intensity and global disease activity in the preceding week (VAS, the duration of morning stiffness and blood tests. Disease activity was assessed using BASDAI and ASDAS-CRP. Serum concentration of IL-10, IL-11, IL-12, IL-15, IL-17, IL-23 and IL-33 was determined. Results : In patients with aSpA, elevated serum concentration of IL-10, IL-15, IL-17 and IL-23 was detected. In the aSpA group we detected higher values of serum concentration of IL-23 and IL-33 in the subgroup with anterior uveitis (83.1 ±184.0 pg/ml vs. 14.0 ±17.1 pg/ml, p < 0.0001 and 45.5 ±71.9 pg/ml vs. 18.4 ±14.3 pg/ml, p < 0.0001, respectively. Additionally, in the subgroup with peripheral arthritis, elevation of serum concentration of IL-12 (249.3 ±246.9 pg/ml vs. 99.9 ±105.9 pg/ml, p = 0.0001 was detected. Patients with preradiological SpA had higher serum concentration of IL-17 than patients with established diagnosis of AS (6.37 ±8.50 pg/ml vs. 2.04 ±2.98 pg/ml, p = 0.0295. No differences in serum concentration of analyzed cytokines were found between the subgroup with low to moderate disease activity and the subgroup with high to very high disease activity. Conclusions : We report that in aSpA patients, compared to controls, elevated serum concentrations of IL-10, IL-15, IL-17 and IL-23 were observed. Some cytokines may

  19. The Bearingless Electrical Machine

    Science.gov (United States)

    Bichsel, J.

    1992-01-01

    Electromagnetic bearings allow the suspension of solids. For rotary applications, the most important physical effect is the force of a magnetic circuit to a high permeable armature, called the MAXWELL force. Contrary to the commonly used MAXWELL bearings, the bearingless electrical machine will take advantage of the reaction force of a conductor carrying a current in a magnetic field. This kind of force, called Lorentz force, generates the torque in direct current, asynchronous and synchronous machines. The magnetic field, which already exists in electrical machines and helps to build up the torque, can also be used for the suspension of the rotor. Besides the normal winding of the stator, a special winding was added, which generates forces for levitation. So a radial bearing, which is integrated directly in the active part of the machine, and the motor use the laminated core simultaneously. The winding was constructed for the levitating forces in a special way so that commercially available standard ac inverters for drives can be used. Besides wholly magnetic suspended machines, there is a wide range of applications for normal drives with ball bearings. Resonances of the rotor, especially critical speeds, can be damped actively.

  20. Asymmetric quantum cloning machines

    International Nuclear Information System (INIS)

    Cerf, N.J.

    1998-01-01

    A family of asymmetric cloning machines for quantum bits and N-dimensional quantum states is introduced. These machines produce two approximate copies of a single quantum state that emerge from two distinct channels. In particular, an asymmetric Pauli cloning machine is defined that makes two imperfect copies of a quantum bit, while the overall input-to-output operation for each copy is a Pauli channel. A no-cloning inequality is derived, characterizing the impossibility of copying imposed by quantum mechanics. If p and p ' are the probabilities of the depolarizing channels associated with the two outputs, the domain in (√p,√p ' )-space located inside a particular ellipse representing close-to-perfect cloning is forbidden. This ellipse tends to a circle when copying an N-dimensional state with N→∞, which has a simple semi-classical interpretation. The symmetric Pauli cloning machines are then used to provide an upper bound on the quantum capacity of the Pauli channel of probabilities p x , p y and p z . The capacity is proven to be vanishing if (√p x , √p y , √p z ) lies outside an ellipsoid whose pole coincides with the depolarizing channel that underlies the universal cloning machine. Finally, the tradeoff between the quality of the two copies is shown to result from a complementarity akin to Heisenberg uncertainty principle. (author)

  1. Determining the ’Gap

    Science.gov (United States)

    2009-05-01

    Army training doctrine, and by adjusting the curriculum of the officer core in order to close the knowledge gap . The author closes by concluding...fight. The research to find these gaps begins with a process trace of doctrine from 1976 to the present, starting with the advent of Active Defense...discovering the one gap , three were found. Upon further examination below, even these initially perceived gaps dissipate under close scrutiny. Gap

  2. GAP junctional communication in brain secondary organizers.

    Science.gov (United States)

    Bosone, Camilla; Andreu, Abraham; Echevarria, Diego

    2016-06-01

    Gap junctions (GJs) are integral membrane proteins that enable the direct cytoplasmic exchange of ions and low molecular weight metabolites between adjacent cells. They are formed by the apposition of two connexons belonging to adjacent cells. Each connexon is formed by six proteins, named connexins (Cxs). Current evidence suggests that gap junctions play an important part in ensuring normal embryo development. Mutations in connexin genes have been linked to a variety of human diseases, although the precise role and the cell biological mechanisms of their action remain almost unknown. Among the big family of Cxs, several are expressed in nervous tissue but just a few are expressed in the anterior neural tube of vertebrates. Many efforts have been made to elucidate the molecular bases of Cxs cell biology and how they influence the morphogenetic signal activity produced by brain signaling centers. These centers, orchestrated by transcription factors and morphogenes determine the axial patterning of the mammalian brain during its specification and regionalization. The present review revisits the findings of GJ composed by Cx43 and Cx36 in neural tube patterning and discuss Cx43 putative enrollment in the control of Fgf8 signal activity coming from the well known secondary organizer, the isthmic organizer. © 2016 The Authors. Development, Growth & Differentiation published by John Wiley & Sons Australia, Ltd on behalf of Japanese Society of Developmental Biologists.

  3. Analysis of rabbit intervertebral disc physiology based on water metabolism. II. Changes in normal intervertebral discs under axial vibratory load

    International Nuclear Information System (INIS)

    Hirano, N.; Tsuji, H.; Ohshima, H.; Kitano, S.; Itoh, T.; Sano, A.

    1988-01-01

    Metabolic changes induced by axial vibratory load to the spine were investigated based on water metabolism in normal intervertebral discs of rabbits with or without pentobarbital anesthesia. Tritiated water concentration in the intervertebral discs of unanesthetized rabbits was reduced remarkably by axial vibration for 30 minutes using the vibration machine developed for this study. Repeated vibratory load for 18 and 42 hours duration showed the recovery of 3 H 2 O concentration of the intervertebral disc without anesthesia. Computer simulation suggested a reduction of blood flow surrounding the intervertebral disc following the vibration stress. However, no reduction of the 3 H 2 O concentration in the intervertebral disc was noted under anesthesia. Emotional stress cannot be excluded as a factor in water metabolism in the intervertebral disc

  4. The Klinger hot gas double axial valve

    International Nuclear Information System (INIS)

    Kruschik, J.; Hiltgen, H.

    1984-01-01

    The Klinger hot gas valve is a medium controlled double axial valve with advanced design features and safety function. It was first proposed by Klinger early in 1976 for the PNP-Project as a containment shut-off for hot helium (918 deg. C and 42 bar), because a market research has shown that such a valve is not state of present techniques. In the first stage of development a feasibility study had to be made by detailed design, calculation and by basic experiments for key components in close collaboration with Interatom/GHT. This was the basis for further design, calculation, construction and experimental work for such a valve prototype within the new development contract. The stage of knowledge to that time revealed the following key priority development areas: Finite element stress analysis for the highly stressed high temperature main components; development of an insulation layout; Detailed experimental tests of functionally important structural components or units of the valve, partly at Klingers (gasstatic bearings, flexible metallic sealing element, aerodynamic and thermohydraulic tests), partly at Interatom (actuator unit and also gasstatic bearings), partly at HRB in Juelich (flexible metallic sealing system, aerodynamic and thermohydraulic tests); Design of a test valve for experimental work in the KVK (test circuit at Interatom) for evaluation of temperature distribution and reliability of operation; Design of a prototype and extensive testing in the KVK

  5. Small axial compressor technology, volume 1

    Science.gov (United States)

    Holman, F. F.; Kidwell, J. R.; Ware, T. C.

    1976-01-01

    A scaled single-stage, highly-loaded, axial-flow transonic compressor was tested at speeds from 70 to 110% design equivalent speed to evaluate the effects of scaling compromises and the individual and combined effects of rotor tip running clearance and rotor shroud casing treatment on the overall and blade element performance. At design speed and 1% tip clearance the stage demonstrated an efficiency of 83.2% at 96.4% design flow and a pressure ratio of 1.865. Casing treatment increased design speed surge margin 2.0 points to 12.8%. Overall performance was essentially unchanged. An increase in rotor running clearance to 2.2%, with smooth casing, reduced design speed peak efficiency 5.7 points, flow by 7.4%, pressure ratio to 1.740, and surge margin to 5.4%. Reinstalling casing treatment regained 3.5 points in design speed peak efficiency, 4.7% flow, increased pressure ratio to 1.800 and surge margin to 8.7%.

  6. Giant Cell Tumors of the Axial Skeleton

    Directory of Open Access Journals (Sweden)

    Maurice Balke

    2012-01-01

    Full Text Available Background. We report on 19 cases of giant cell tumor of bone (GCT affecting the spine or sacrum and evaluate the outcome of different treatment modalities. Methods. Nineteen patients with GCT of the spine (=6 or sacrum (=13 have been included in this study. The mean followup was 51.6 months. Ten sacral GCT were treated by intralesional procedures of which 4 also received embolization, and 3 with irradiation only. All spinal GCT were surgically treated. Results. Two (15.4% patients with sacral and 4 (66.7% with spinal tumors had a local recurrence, two of the letter developed pulmonary metastases. One local recurrence of the spine was successfully treated by serial arterial embolization, a procedure previously described only for sacral tumors. At last followup, 9 patients had no evidence of disease, 8 had stable disease, 1 had progressive disease, 1 died due to disease. Six patients had neurological deficits. Conclusions. GCT of the axial skeleton have a high local recurrence rate. Neurological deficits are common. En-bloc spondylectomy combined with embolization is the treatment of choice. In case of inoperability, serial arterial embolization seems to be an alternative not only for sacral but also for spinal tumors.

  7. Axial channeling of boron ions into silicon

    International Nuclear Information System (INIS)

    La Ferla, A.; Galvagno, G.; Raineri, V.; Setola, R.; Rimini, E.; Carnera, A.; Gasparotto, A.

    1992-01-01

    Channeling boron implants were performed into (100) and (110) silicon substrates in the energy range 80-700 keV. The dose ranged between 3.5x10 11 and 1x10 15 atoms/cm 2 . The axial channeling concentration profiles of implanted B + were compared with that obtained for incidence along the random direction of the crystal and with that obtained by implantation in amorphous silicon. The electrical and chemical boron distributions were obtained by spreading resistance and secondary ion mass spectrometry measurements, respectively. The inelastic stopping power, S c , was extracted from the experimental maximum ranges for the [100] and [110] axis. The energy dependence of the electronic stopping power is given by S e = KE p with p [100] = 0.469±0.010 and p [110] = 0.554±0.004. Simulations obtained by the MARLOWE code, using the Oen-Robinson impact parameter dependent formula, for the electronic energy loss reproduce quite well the experimental depth profiles. (orig.)

  8. Axial sheath dynamics in a plasma focus

    International Nuclear Information System (INIS)

    Soliman, H.M.; El-Khalafawy, T.A.; Masoud, M.M.

    1990-01-01

    This paper presents the result of investigation with a 10 kJ Mather type plasma focus. It is operated in hydrogen gas at ambient pressure of 0.15--1 torr and charging voltage of 8--11 kV. Radial distribution of the current sheath density with axial distance has been estimated. Plasma rotation in the expansion chamber in the absence of external magnetic field has been detected. A plasma flare from the plasma focus region propagating in the radial direction has been observed. Streak photography shows two plasma streams flowing simultaneously out of the muzzle. The mean energy of the electron beam ejected from the pinch region of the focused plasma, was measured by retarding field analyzer to be 0.32 keV. The electron temperature of the plasma focus at peak compression was determined by measuring the X-ray intensity as a function of absorber thickness at a distance of 62 cm from the focus. The electron temperature has been found to 3 keV

  9. Relation between axial length and ocular parameters

    Directory of Open Access Journals (Sweden)

    Xue-Qiu Yang

    2013-09-01

    Full Text Available AIM: To investigatethe relation between axial length(AL, age and ocular parameters.METHODS: A total of 360 subjects(360 eyeswith emmetropia or myopia were recruited. Refraction, center corneal thickness(CCT, AL, intraocular pressure(IOPwere measured by automatic-refractor, Pachymeter, A-mode ultrasound and non-contact tonometer, respectively. Corneal curvature(CC, anterior chamber depth(ACDand white-to-white distance(WWDwere measured by Orbscan II. Three dimensional frequency domain coherent optical tomography(3D-OCTwas used to examine the retinal nerve fiber layer thickness(RNFLT. The Pearson correlation coefficient(rand multiple regression analysis were performed to evaluate the relationship between AL, age and ocular parameters.RESULTS: The average AL was 24.15±1.26mm. With elongation of the AL, spherical equivalent(SE(r=-0.742,Pr=-0.395, Pr=-0.374, Pr=0.411, Pr=0.099, P=0.060and WWD(r=0.061, P=0.252. There was also a significant correlation between AL and age(P=0.001, SE(PPPCONCLUSION: In longer eyes, there is a tendency toward myopia, a flatter cornea, a deeper ACD and a thinner RNFLT. Age is an influencing factor for the AL as well.

  10. Analysis of SONACO axial cooling experiments

    International Nuclear Information System (INIS)

    Sigg, B.; Dury, T.V.; Hudina, M.

    1994-01-01

    The SONACO test rig contained a sodium-cooled, electrically heated 37-pin bundle. On this rig, a series of forced, mixed and natural convection experiments have been performed with the aim of contributing to the understanding of thermal-hydraulic phenomena and providing data for code validation for a subassembly at decay heat power level with low flow or stagnant coolant. The test section and especially the heater pins were equipped with an extensive number of chromel-alumel thermocouples. In addition, special permanent-magnet probes were used for measuring local velocities. In this paper we give a survey of results from axial cooling experiments, where heat was removed by natural convection to a cooling coil situated in the coolant channel (plenum) above the bundle. The experimental conditions led to turbulent convection with a slowly varying, large scale flow pattern. It is shown that a power tilt in the bundle reduces these fluctuations but does not eliminate them. For the uniformly heated bundle, aglebraic expressions for the average turbulent heat flux as well as for temperature and velocity fluctuations are derived from a second-moments model and compared with experimental data. Furthermore, heat transfer in the plenum and the consequences of the SONACO experiments for the coolability of reactor fuel elements under loss-of-flow conditions are discussed. ((orig.))

  11. Nucleon axial coupling from Lattice QCD

    Science.gov (United States)

    Cheng Chang, Chia; Nicholson, Amy; Rinaldi, Enrico; Berkowitz, Evan; Garron, Nicolas; Brantley, David; Monge-Camacho, Henry; Monahan, Chris; Bouchard, Chris; Clark, M. A.; Joó, Bálint; Kurth, Thorsten; Orginos, Kostas; Vranas, Pavlos; Walker-Loud, André

    2018-03-01

    We present state-of-the-art results from a lattice QCD calculation of the nucleon axial coupling, gA, using Möbius Domain-Wall fermions solved on the dynamical Nf = 2 + 1 + 1 HISQ ensembles after they are smeared using the gradient-flow algorithm. Relevant three-point correlation functions are calculated using a method inspired by the Feynman-Hellmann theorem, and demonstrate significant improvement in signal for fixed stochastic samples. The calculation is performed at five pion masses of mπ {400, 350, 310, 220, 130} MeV, three lattice spacings of a {0.15, 0.12, 0.09} fm, and we do a dedicated volume study with mπL {3.22, 4.29, 5.36}. Control over all relevant sources of systematic uncertainty are demonstrated and quantified. We achieve a preliminary value of gA = 1.285(17), with a relative uncertainty of 1.33%.

  12. Multimode interaction in axially excited cylindrical shells

    Directory of Open Access Journals (Sweden)

    Silva F. M. A.

    2014-01-01

    Full Text Available Cylindrical shells exhibit a dense frequency spectrum, especially near the lowest frequency range. In addition, due to the circumferential symmetry, frequencies occur in pairs. So, in the vicinity of the lowest natural frequencies, several equal or nearly equal frequencies may occur, leading to a complex dynamic behavior. So, the aim of the present work is to investigate the dynamic behavior and stability of cylindrical shells under axial forcing with multiple equal or nearly equal natural frequencies. The shell is modelled using the Donnell nonlinear shallow shell theory and the discretized equations of motion are obtained by applying the Galerkin method. For this, a modal solution that takes into account the modal interaction among the relevant modes and the influence of their companion modes (modes with rotational symmetry, which satisfies the boundary and continuity conditions of the shell, is derived. Special attention is given to the 1:1:1:1 internal resonance (four interacting modes. Solving numerically the governing equations of motion and using several tools of nonlinear dynamics, a detailed parametric analysis is conducted to clarify the influence of the internal resonances on the bifurcations, stability boundaries, nonlinear vibration modes and basins of attraction of the structure.

  13. Human-Machine Communication

    International Nuclear Information System (INIS)

    Farbrot, J.E.; Nihlwing, Ch.; Svengren, H.

    2005-01-01

    New requirements for enhanced safety and design changes in process systems often leads to a step-wise installation of new information and control equipment in the control room of older nuclear power plants, where nowadays modern digital I and C solutions with screen-based human-machine interfaces (HMI) most often are introduced. Human factors (HF) expertise is then required to assist in specifying a unified, integrated HMI, where the entire integration of information is addressed to ensure an optimal and effective interplay between human (operators) and machine (process). Following a controlled design process is the best insurance for ending up with good solutions. This paper addresses the approach taken when introducing modern human-machine communication in the Oskarshamn 1 NPP, the results, and the lessons learned from this work with high operator involvement seen from an HF point of view. Examples of possibilities modern technology might offer for the operators are also addressed. (orig.)

  14. Machines and Metaphors

    Directory of Open Access Journals (Sweden)

    Ángel Martínez García-Posada

    2016-10-01

    Full Text Available The edition La ley del reloj. Arquitectura, máquinas y cultura moderna (Cátedra, Madrid, 2016 registers the useful paradox of the analogy between architecture and technique. Its author, the architect Eduardo Prieto, also a philosopher, professor and writer, acknowledges the obvious distance from machines to buildings, so great that it can only be solved using strange comparisons, since architecture does not move nor are the machines habitable, however throughout the book, from the origin of the metaphor of the machine, with clarity in his essay and enlightening erudition, he points out with certainty some concomitances of high interest, drawing throughout history a beautiful cartography of the fruitful encounter between organics and mechanics.

  15. Machine Learning for Security

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    Applied statistics, aka ‘Machine Learning’, offers a wealth of techniques for answering security questions. It’s a much hyped topic in the big data world, with many companies now providing machine learning as a service. This talk will demystify these techniques, explain the math, and demonstrate their application to security problems. The presentation will include how-to’s on classifying malware, looking into encrypted tunnels, and finding botnets in DNS data. About the speaker Josiah is a security researcher with HP TippingPoint DVLabs Research Group. He has over 15 years of professional software development experience. Josiah used to do AI, with work focused on graph theory, search, and deductive inference on large knowledge bases. As rules only get you so far, he moved from AI to using machine learning techniques identifying failure modes in email traffic. There followed digressions into clustered data storage and later integrated control systems. Current ...

  16. Chatter and machine tools

    CERN Document Server

    Stone, Brian

    2014-01-01

    Focussing on occurrences of unstable vibrations, or Chatter, in machine tools, this book gives important insights into how to eliminate chatter with associated improvements in product quality, surface finish and tool wear. Covering a wide range of machining processes, including turning, drilling, milling and grinding, the author uses his research expertise and practical knowledge of vibration problems to provide solutions supported by experimental evidence of their effectiveness. In addition, this book contains links to supplementary animation programs that help readers to visualise the ideas detailed in the text. Advancing knowledge in chatter avoidance and suggesting areas for new innovations, Chatter and Machine Tools serves as a handbook for those desiring to achieve significant reductions in noise, longer tool and grinding wheel life and improved product finish.

  17. A Thin Lens Model for Charged-Particle RF Accelerating Gaps

    Energy Technology Data Exchange (ETDEWEB)

    Allen, Christopher K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-07-01

    Presented is a thin-lens model for an RF accelerating gap that considers general axial fields without energy dependence or other a priori assumptions. Both the cosine and sine transit time factors (i.e., Fourier transforms) are required plus two additional functions; the Hilbert transforms the transit-time factors. The combination yields a complex-valued Hamiltonian rotating in the complex plane with synchronous phase. Using Hamiltonians the phase and energy gains are computed independently in the pre-gap and post-gap regions then aligned using the asymptotic values of wave number. Derivations of these results are outlined, examples are shown, and simulations with the model are presented.

  18. Investigation of axial positioning for flexural compressors

    Science.gov (United States)

    Riggle, Peter

    1991-01-01

    The testing of the research compressor is presented. The research compressor was assembled and disassembled in order to show the consistency in which the piston and rod could be aligned with a .0004 inch radial gap around the piston. A full set of tests was completed for the first assembly, which is referred to as assembly no. 1. The compressor was disassembled and assembled a second time (assembly no. 2). Assembly no. 2 was only tested statically due to the time constraint. Results are discussed.

  19. Clojure for machine learning

    CERN Document Server

    Wali, Akhil

    2014-01-01

    A book that brings out the strengths of Clojure programming that have to facilitate machine learning. Each topic is described in substantial detail, and examples and libraries in Clojure are also demonstrated.This book is intended for Clojure developers who want to explore the area of machine learning. Basic understanding of the Clojure programming language is required, but thorough acquaintance with the standard Clojure library or any libraries are not required. Familiarity with theoretical concepts and notation of mathematics and statistics would be an added advantage.

  20. Machine learning systems

    Energy Technology Data Exchange (ETDEWEB)

    Forsyth, R

    1984-05-01

    With the dramatic rise of expert systems has come a renewed interest in the fuel that drives them-knowledge. For it is specialist knowledge which gives expert systems their power. But extracting knowledge from human experts in symbolic form has proved arduous and labour-intensive. So the idea of machine learning is enjoying a renaissance. Machine learning is any automatic improvement in the performance of a computer system over time, as a result of experience. Thus a learning algorithm seeks to do one or more of the following: cover a wider range of problems, deliver more accurate solutions, obtain answers more cheaply, and simplify codified knowledge. 6 references.

  1. Machine tool evaluation

    International Nuclear Information System (INIS)

    Lunsford, B.E.

    1976-01-01

    Continued improvement in numerical control (NC) units and the mechanical components used in the construction of today's machine tools, necessitate the use of more precise instrumentation to calibrate and determine the capabilities of these systems. It is now necessary to calibrate most tape-control lathes to a tool-path positioning accuracy of +-300 microinches in the full slide travel and, on some special turning and boring machines, a capability of +-100 microinches must be achieved. The use of a laser interferometer to determine tool-path capabilities is described

  2. Electrical machines & their applications

    CERN Document Server

    Hindmarsh, J

    1984-01-01

    A self-contained, comprehensive and unified treatment of electrical machines, including consideration of their control characteristics in both conventional and semiconductor switched circuits. This new edition has been expanded and updated to include material which reflects current thinking and practice. All references have been updated to conform to the latest national (BS) and international (IEC) recommendations and a new appendix has been added which deals more fully with the theory of permanent-magnets, recognising the growing importance of permanent-magnet machines. The text is so arra

  3. Machine shop basics

    CERN Document Server

    Miller, Rex

    2004-01-01

    Use the right tool the right wayHere, fully updated to include new machines and electronic/digital controls, is the ultimate guide to basic machine shop equipment and how to use it. Whether you're a professional machinist, an apprentice, a trade student, or a handy homeowner, this fully illustrated volume helps you define tools and use them properly and safely. It's packed with review questions for students, and loaded with answers you need on the job.Mark Richard Miller is a Professor and Chairman of the Industrial Technology Department at Texas A&M University in Kingsville, T

  4. Electrical machines diagnosis

    CERN Document Server

    Trigeassou, Jean-Claude

    2013-01-01

    Monitoring and diagnosis of electrical machine faults is a scientific and economic issue which is motivated by objectives for reliability and serviceability in electrical drives.This book provides a survey of the techniques used to detect the faults occurring in electrical drives: electrical, thermal and mechanical faults of the electrical machine, faults of the static converter and faults of the energy storage unit.Diagnosis of faults occurring in electrical drives is an essential part of a global monitoring system used to improve reliability and serviceability. This diagnosis is perf

  5. Neutron irradiation therapy machine

    International Nuclear Information System (INIS)

    1980-01-01

    Conventional neutron irradiation therapy machines, based on the use of cyclotrons for producing neutron beams, use a superconducting magnet for the cyclotron's magnetic field. This necessitates complex liquid He equipment and presents problems in general hospital use. If conventional magnets are used, the weight of the magnet poles considerably complicates the design of the rotating gantry. Such a therapy machine, gantry and target facilities are described in detail. The use of protons and deuterons to produce the neutron beams is compared and contrasted. (U.K.)

  6. Man - Machine Communication

    CERN Document Server

    Petersen, Peter; Nielsen, Henning

    1984-01-01

    This report describes a Man-to-Machine Communication module which together with a STAC can take care of all operator inputs from the touch-screen, tracker balls and mechanical buttons. The MMC module can also contain a G64 card which could be a GPIB driver but many other G64 cards could be used. The soft-ware services the input devices and makes the results accessible from the CAMAC bus. NODAL functions for the Man Machine Communication is implemented in the STAC and in the ICC.

  7. MRTD: man versus machine

    Science.gov (United States)

    van Rheenen, Arthur D.; Taule, Petter; Thomassen, Jan Brede; Madsen, Eirik Blix

    2018-04-01

    We present Minimum-Resolvable Temperature Difference (MRTD) curves obtained by letting an ensemble of observers judge how many of the six four-bar patterns they can "see" in a set of images taken with different bar-to-background contrasts. The same images are analyzed using elemental signal analysis algorithms and machine-analysis based MRTD curves are obtained. We show that by adjusting the minimum required signal-to-noise ratio the machine-based MRTDs are very similar to the ones obtained with the help of the human observers.

  8. Advances in Machine Technology.

    Science.gov (United States)

    Clark, William R; Villa, Gianluca; Neri, Mauro; Ronco, Claudio

    2018-01-01

    Continuous renal replacement therapy (CRRT) machines have evolved into devices specifically designed for critically ill over the past 40 years. In this chapter, a brief history of this evolution is first provided, with emphasis on the manner in which changes have been made to address the specific needs of the critically ill patient with acute kidney injury. Subsequently, specific examples of technology developments for CRRT machines are discussed, including the user interface, pumps, pressure monitoring, safety features, and anticoagulation capabilities. © 2018 S. Karger AG, Basel.

  9. Design and analysis of a toroidal tester for the measurement of core losses under axial compressive stress

    Energy Technology Data Exchange (ETDEWEB)

    Alatawneh, Natheer, E-mail: natheer80@yahoo.com [Department of Mining and Materials Engineering, McGill University, QC H3A 0G4 (Canada); Rahman, Tanvir; Lowther, David A. [Department of Electrical and Computer Engineering, McGill University, QC H3A 0E9 (Canada); Chromik, Richard [Department of Mining and Materials Engineering, McGill University, QC H3A 0G4 (Canada)

    2017-06-15

    Highlights: • Develop a toroidal tester for magnetic measurements under compressive axial stress. • The shape of the toroidal ring has been verified using 3D stress analysis. • The developed design has been prototyped, and measurements were carried out. • Physical explanations for the core loss trend due to stress are provided. - Abstract: Electric machine cores are subjected to mechanical stresses due to manufacturing processes. These stresses include radial, circumferential and axial components that may have significant influences on the magnetic properties of the electrical steel and hence, on the output and efficiencies of electrical machines. Previously, most studies of iron losses due to mechanical stress have considered only radial and circumferential components. In this work, an improved toroidal tester has been designed and developed to measure the core losses and the magnetic properties of electrical steel under a compressive axial stress. The shape of the toroidal ring has been verified using 3D stress analysis. Also, 3D electromagnetic simulations show a uniform flux density distribution in the specimen with a variation of 0.03 T and a maximum average induction level of 1.5 T. The developed design has been prototyped, and measurements were carried out using a steel sample of grade 35WW300. Measurements show that applying small mechanical stresses normal to the sample thickness rises the delivered core losses, then the losses decrease continuously as the stress increases. However, the drop in core losses at high stresses does not go lower than the free-stress condition. Physical explanations for the observed trend of core losses as a function of stress are provided based on core loss separation to the hysteresis and eddy current loss components. The experimental results show that the effect of axial compressive stress on magnetic properties of electrical steel at high level of inductions becomes less pronounced.

  10. Stall inception and warning in a single-stage transonic axial compressor with axial skewed slot casing treatment

    International Nuclear Information System (INIS)

    Lim, Byeung Jun; Kwon, Se Jin; Park, Tae Choon

    2014-01-01

    Characteristic changes in the stall inception in a single-stage transonic axial compressor with an axial skewed slot casing treatment were investigated experimentally. A rotating stall occurred intermittently in a compressor with an axial skewed slot, whereas spike-type rotating stalls occurred in the case of smooth casing. The axial skewed slot suppressed stall cell growth and increased the operating range. A mild surge, the frequency of which is the Helmholtz frequency of the compressor system, occurred with the rotating stall. The irregularity in the pressure signals at the slot bottom increased decreasing flow rate. An autocorrelation-based stall warning method was applied to the measured pressure signals. Results estimate and warn against the stall margin in a compressor with an axial skewed slot.

  11. Development of a large scale structure in the rod gap region for turbulent in-line flow through closely spaced rod arrays

    International Nuclear Information System (INIS)

    Hooper, J.D.

    1984-01-01

    Experimental studies of developed axial single-phase flow through closely spaced rod arrays have shown, with reducing p/d ratio, the development of high axial and azimuthal turbulence intensities in the rod gap region. Associated with this is the existence of very high levels of the azimuthal Reynolds shear stress component either side of the rod gap centre. Spatial correlation analysis of the three turbulent velocity components has shown a large scale coherent and almost periodic structure in the rod gap region. The structure is markedly different to the currently accepted secondary flow model. 14 references

  12. Remote maintenance for fusion: Requirements vs technology gap

    International Nuclear Information System (INIS)

    Davis, F.C.; Kuban, D.P.

    1989-01-01

    Today's remote handling technology was developed in response to the remote maintenance (RM) requirements of the fission community's nuclear fuel recycle process. The needs of the fusion community present new challenges to the remote handling experts of the world. New difficulties are superimposed on the difficulties experienced in maintaining fission processes. Today's technology must be enhanced to respond to the RM needs of these future huge investments. This paper first discusses the current RM needs for fusion based on existing facilities and designs of future machines. It then exposes the gap between these requirements and existing RM technology and recommends ways to extend the state of the art to close this gap

  13. Mind the Gap!

    DEFF Research Database (Denmark)

    Schmidt, Kjeld; Simone, Carla

    2000-01-01

    CSCW at large seems to be pursuing two diverging strategies: on one hand a strategy aiming at coordination technologies that reduce the complexity of coordinating cooperative activities by regulating the coordinative interactions, and on the other hand a strategy that aims at radically flexible m...... and blended in the course of real world cooperative activities. On the basis of this discussion the paper outlines an approach which may help CSCW research to bridge this gap....... means of interaction which do not regulate interaction but rather leave it to the users to cope with the complexity of coordinating their activities. As both strategies reflect genuine requirements, we need to address the issue of how the gap can be bridged, that is, how the two strategies can...

  14. Closing the gap

    International Nuclear Information System (INIS)

    Moxon, Suzanne

    1999-01-01

    The problem of fish going through turbines at hydroelectric power plants and the growing concern over the survival rate of salmon at the US Army Corps operated Bonneville lock and dam on the Columbia river in the Pacific Northwest is discussed. The protection of the fish, the assessment of the hazards facing fish passing through turbines, the development of a new turbine, and improved turbine efficiency that reduces cavitation, turbulence and shear flow are examined. The closing of the gap between the turbine blades, hub and discharge ring to increase efficiency and reduce the risk to fish, and the development of the minimum gap runner (MGR) are described, and the lower maximum permitted power output of MGR is noted. (UK)

  15. Machine speech and speaking about machines

    Energy Technology Data Exchange (ETDEWEB)

    Nye, A. [Univ. of Wisconsin, Whitewater, WI (United States)

    1996-12-31

    Current philosophy of language prides itself on scientific status. It boasts of being no longer contaminated with queer mental entities or idealist essences. It theorizes language as programmable variants of formal semantic systems, reimaginable either as the properly epiphenomenal machine functions of computer science or the properly material neural networks of physiology. Whether or not such models properly capture the physical workings of a living human brain is a question that scientists will have to answer. I, as a philosopher, come at the problem from another direction. Does contemporary philosophical semantics, in its dominant truth-theoretic and related versions, capture actual living human thought as it is experienced, or does it instead reflect, regardless of (perhaps dubious) scientific credentials, pathology of thought, a pathology with a disturbing social history.

  16. Minding the Gap

    Energy Technology Data Exchange (ETDEWEB)

    Firestone, Millicent Anne [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-02-23

    Neutron & X-ray scattering provides nano- to meso-scale details of complex fluid structure; 1D electronic density maps dervied from SAXS yield molecular level insights; Neutron reflectivity provides substructure details of substrate supported complex fluids; Complex fluids composition can be optimized to support a wide variety of both soluble and membrane proteins; The water gap dimensions can be finely tuned through polymer component.

  17. Gender gap in entrepreneurship

    OpenAIRE

    Startienė, Gražina; Remeikienė, Rita

    2008-01-01

    The article considers a significant global issue - gender gap starting and developing own business. The field of business was for a long time reserved to men, thus, despite of an increasing number of female entrepreneurs during last decade, the number of female entrepreneurs in Europe, including Lithuania, remains lower than the one of male entrepreneurs. According to the data of various statistical sources, an average ratio of enterprises newly established by men and women in EU countries is...

  18. Mind the Gap

    Science.gov (United States)

    Fairbanks, Terry; Savage, Erica; Adams, Katie; Wittie, Michael; Boone, Edna; Hayden, Andrew; Barnes, Janey; Hettinger, Zach; Gettinger, Andrew

    2016-01-01

    Summary Objective Decisions made during electronic health record (EHR) implementations profoundly affect usability and safety. This study aims to identify gaps between the current literature and key stakeholders’ perceptions of usability and safety practices and the challenges encountered during the implementation of EHRs. Materials and Methods Two approaches were used: a literature review and interviews with key stakeholders. We performed a systematic review of the literature to identify usability and safety challenges and best practices during implementation. A total of 55 articles were reviewed through searches of PubMed, Web of Science and Scopus. We used a qualitative approach to identify key stakeholders’ perceptions; semi-structured interviews were conducted with a diverse set of health IT stakeholders to understand their current practices and challenges related to usability during implementation. We used a grounded theory approach: data were coded, sorted, and emerging themes were identified. Conclusions from both sources of data were compared to identify areas of misalignment. Results We identified six emerging themes from the literature and stakeholder interviews: cost and resources, risk assessment, governance and consensus building, customization, clinical work-flow and usability testing, and training. Across these themes, there were misalignments between the literature and stakeholder perspectives, indicating major gaps. Discussion Major gaps identified from each of six emerging themes are discussed as critical areas for future research, opportunities for new stakeholder initiatives, and opportunities to better disseminate resources to improve the implementation of EHRs. Conclusion Our analysis identified practices and challenges across six different emerging themes, illustrated important gaps, and results suggest critical areas for future research and dissemination to improve EHR implementation. PMID:27847961

  19. A Hybrid Excited Machine with Flux Barriers and Magnetic Bridges

    Directory of Open Access Journals (Sweden)

    Marcin Wardach

    2018-03-01

    Full Text Available In this paper, an U-shape flux barrier rotor concept for a hybrid excited synchronous machine with flux magnetic bridges fixed on the rotor is presented. Using 3D finite element analysis, the influence of axial flux bridges on the field-weakening and -strengthening characteristics, electromagnetic torque, no-load magnetic flux linkage, rotor iron losses and back electromotive force is shown. Three different rotor designs are analyzed. Furthermore, the field control characteristics depending on additional DC control coil currents are shown.

  20. Design of rotating electrical machines

    CERN Document Server

    Pyrhonen , Juha; Hrabovcova , Valeria

    2013-01-01

    In one complete volume, this essential reference presents an in-depth overview of the theoretical principles and techniques of electrical machine design. This timely new edition offers up-to-date theory and guidelines for the design of electrical machines, taking into account recent advances in permanent magnet machines as well as synchronous reluctance machines. New coverage includes: Brand new material on the ecological impact of the motors, covering the eco-design principles of rotating electrical machinesAn expanded section on the design of permanent magnet synchronous machines, now repo

  1. MV controlled spark gap

    International Nuclear Information System (INIS)

    Evdokimovich, V.M.; Evlampiev, S.B.; Korshunov, G.S.; Nikolaev, V.A.; Sviridov, Yu.F.; Khmyrov, V.V.

    1980-01-01

    A megavolt gas-filled trigatron gap with a sectional gas-discharge chamber having a more than three-fold range of operating voltages is described. The discharge chamber consists of ten sections, each 70 mm thick, made of organic glass. The sections are separated one from another by aluminium gradient rings to which ohmic voltage divider is connected. Insulational sections and gradient rings are braced between themselves by means of metal flanges through gaskets made of oil-resistant rubber with the help of fiberglass-laminate pins. The gap has two electrodes 110 mm in diameter. The trigatron ignition assembly uses a dielectric bushing projecting over the main electrode plane. Use has been made of a gas mixture containing 10% of SF 6 and 90% of air making possible to ensure stable gap operation without readjusting in the voltage range from 0.4 to 1.35 MV. The operation time lag in this range is equal to 10 μs at a spread of [ru

  2. Conservative axial burnup distributions for actinide-only burnup credit

    International Nuclear Information System (INIS)

    Kang, C.; Lancaster, D.

    1997-11-01

    Unlike the fresh fuel approach, which assumes the initial isotopic compositions for criticality analyses, any burnup credit methodology must address the proper treatment of axial burnup distributions. A straightforward way of treating a given axial burnup distribution is to segment the fuel assembly into multiple meshes and to model each burnup mesh with the corresponding isotopic compositions. Although this approach represents a significant increase in modeling efforts compared to the uniform average burnup approach, it can adequately determine the reactivity effect of the axial burnup distribution. A major consideration is what axial burnup distributions are appropriate for use in light of many possible distributions depending on core operating conditions and histories. This paper summarizes criticality analyses performed to determine conservative axial burnup distributions. The conservative axial burnup distributions presented in this paper are included in the Topical Report on Actinide-Only Burnup Credit for Pressurized Water Reactor Spent Nuclear Fuel Packages, Revision 1 submitted in May 1997 by the US Department of Energy (DOE) to the US Nuclear Regulatory Commission (NRC). When approved by NRC, the conservative axial burnup distributions may be used to model PWR spent nuclear fuel for the purpose of gaining actinide only burnup credit

  3. Axial currents and nuclear spin orientation

    International Nuclear Information System (INIS)

    Minamisono, T.; Nojiri, Y.; Matsuta, K.

    1984-01-01

    This paper discusses the symmetries in the phenomena in which weak interaction is involved are largely violated, and it is still the up-to-date fore-front to study the structure of the nuclear weak currents and to learn the limitations on the applicabilities of the various relevant conservation laws as well as the nuclear structures studied by the β-decay. In this meeting, research works on the β-decay processes for the past 10 years have focused on the recoil order experiments designed to determine the limits of validity of the conserved vector current (CVC) theory and to test the G parity conservation i.e. the search for the second class currents (SCC), as well as to study the structure of the axial currents. Concerning the SCC, after intensive studies, but with not conclusive results, on the ft values of mirror β-decays in the early seventies, the correlation-type measurements on mass A=8, 12, 19 and 20 systems have been also carried out in various laboratories from 1975. Among those, concerns have been with the mass A=12 nuclear triad, /sup 12/B-/sup 12/C-/sup 12/N, the energy diagram of which is well known. The choice of this triad is because of the test done for the strong CVC predictions using the spectrum shapes of β-rays combined with the experimental analogue γ-width in /sup 12/C as well as those relevant nuclear structures. Thus, this A=12 system provides the best testing ground for the research described above

  4. Making molecular machines work

    NARCIS (Netherlands)

    Browne, Wesley R.; Feringa, Ben L.

    2006-01-01

    In this review we chart recent advances in what is at once an old and very new field of endeavour the achievement of control of motion at the molecular level including solid-state and surface-mounted rotors, and its natural progression to the development of synthetic molecular machines. Besides a

  5. Massively collaborative machine learning

    NARCIS (Netherlands)

    Rijn, van J.N.

    2016-01-01

    Many scientists are focussed on building models. We nearly process all information we perceive to a model. There are many techniques that enable computers to build models as well. The field of research that develops such techniques is called Machine Learning. Many research is devoted to develop

  6. Turbulence and Flying Machines

    Indian Academy of Sciences (India)

    other to make the aircraft roll. For example, a downward dis- placement of the left aileron causes the airplane to roll to the right. In Figure 4 the elevators have been deflected downwards, giving rise to a 'nose-down' moment about the pitch axis. Delaying Turbulence. In the last few decades, flying machines have proliferated ...

  7. Consuming a Machinic Servicescape

    OpenAIRE

    Hietanen, Joel; Andéhn, Mikael; Iddon, Thom; Denny, Iain; Ehnhage, Anna

    2016-01-01

    Consumer encounters with servicescapes tend to emphasize the harmonic tendency of their value-creating potential. We contest this assumption from a critical non-representational perspective that foregrounds the machinic and repressive potentiality of such con- sumption contexts. We offer the airport servicescape as an illustrative example. 

  8. War Machines and Ethics

    DEFF Research Database (Denmark)

    Nielsen, Thomas Galasz; Buhl, Kenneth Øhlenschlæger

    2018-01-01

    and save military lives. However, this opens up for discussions about ethical dilemmas about machines that autonomously are able to kill humans: What is an autonomous weapons system? What laws covers the use of fully autonomous weapons systems? Should it apply to International Humanitarian Law?...

  9. GPK heading machine

    Energy Technology Data Exchange (ETDEWEB)

    Krmasek, J.; Novosad, K.

    1981-01-01

    This article evaluates performance tests of the Soviet made GPK heading machine carried out in 4 coal mines in Czechoslovakia (Ostrava-Karvina region and Kladno mines). GPK works in coal seams and rocks with compression strength of 40 to 50 MPa. Dimensions of the tunnel are height 1.8 to 3.8 m and width 2.6 to 4.7 m, tunnel gradient plus to minus 10 degrees. GPK weighs 16 t, its conical shaped cutting head equipped with RKS-1 cutting tools is driven by an electric motor with 55 kW capacity. Undercarriage of the GPK, gathering-arm loader, hydraulic system, electric system and dust supression system (water spraying or pneumatic section) are characterized. Specifications of GPK heading machines are compared with PK-3r and F8 heading machines. Reliability, number of failures, dust level, noise, productivity depending on compression strength of rocks, heading rate in coal and in rocks, energy consumption, performance in inclined tunnels, and cutting tool wear are evaluated. Tests show that GPK can be used to drive tunnels in coal with rock constituting up to 50% of the tunnel crosscut, as long as rock compression strength does not exceed 50 MPa. In rocks characterized by higher compression strength cutting tool wear sharply increases. GPK is characterized by higher productivity than that of the PK-3r heading machine. Among the weak points of the GPK are: unsatisfactory reliability and excessive wear of its elements. (4 refs.) (In Czech)

  10. A Turing Machine Simulator.

    Science.gov (United States)

    Navarro, Aaron B.

    1981-01-01

    Presents a program in Level II BASIC for a TRS-80 computer that simulates a Turing machine and discusses the nature of the device. The program is run interactively and is designed to be used as an educational tool by computer science or mathematics students studying computational or automata theory. (MP)

  11. Machine Dictation and Transcription.

    Science.gov (United States)

    Harvey, Evelyn; And Others

    This instructional package contains both an instructor's manual and a student's manual for a course in machine dictation and transcription. The instructor's manual contains an overview with tips on teaching the course, letters for dictation, and a key to the letters. The student's manual contains an overview of the course and of the skills needed…

  12. Natural Nano-Machines

    Indian Academy of Sciences (India)

    Administrator

    transport, ion pump, ATP syn- thase. A popularized ..... gas. A lice: I could not understand how A T P m olecules serve as fuels for m olecular m achines. ..... [16] V Balzani, M Venturi and A Credi, Molecular Devices and Machines: a Journey into ...

  13. ADAM: ADaptive Autonomous Machine

    NARCIS (Netherlands)

    van Oosten, Daan C.; Nijenhuis, Lucas F.J.; Bakkers, André; Vervoort, Wiek

    1996-01-01

    This paper describes a part of the development of an adaptive autonomous machine that is able to move in an unknown world extract knowledge out of the perceived data, has the possibility to reason, and finally has the capability to exchange experiences and knowledge with other agents. The agent is

  14. Machine Parts as Metaphor.

    Science.gov (United States)

    Porter, Gerald

    The connection between Language for Specific Purposes (LSP) and literature is discussed with examples of technical vocabulary drawn from a variety of writers, with particular attention to a sketch by the British dramatist Harold Pinter, "Trouble in the Works," which makes extensive use of the terminology of machine parts. It is noted…

  15. Machine-Learning Research

    OpenAIRE

    Dietterich, Thomas G.

    1997-01-01

    Machine-learning research has been making great progress in many directions. This article summarizes four of these directions and discusses some current open problems. The four directions are (1) the improvement of classification accuracy by learning ensembles of classifiers, (2) methods for scaling up supervised learning algorithms, (3) reinforcement learning, and (4) the learning of complex stochastic models.

  16. Axial displacements in external and internal implant-abutment connection.

    Science.gov (United States)

    Lee, Ji-Hye; Kim, Dae-Gon; Park, Chan-Jin; Cho, Lee-Ra

    2014-02-01

    The purpose of this study was to evaluate the axial displacement of the abutments during clinical procedures by the tightening torque and cyclic loading. Two different implant-abutment connection systems were used (external butt joint connection [EXT]; internal tapered conical connection [INT]). The master casts with two implant replicas, angulated 10° from each other, were fabricated for each implant connection system. Four types of impression copings were assembled and tightened with the corresponding implants (hex transfer impression coping, non-hex transfer impression coping, hex pick-up impression coping, non-hex pick-up impression coping). Resin splinted abutments and final prosthesis were assembled. The axial displacement was measured from the length of each assembly, which was evaluated repeatedly, after 30 Ncm torque tightening. After 250 N cyclic loading of final prosthesis for 1,000,000 cycles, additional axial displacement was recorded. The mean axial displacement was statistically analyzed (repeated measured ANOVA). There was more axial displacement in the INT group than that of the EXT group in impression copings, resin splinted abutments, and final prosthesis. Less axial displacement was found at 1-piece non-hex transfer type impression coping than other type of impression copings in the INT group. There was more axial displacement at the final prosthesis than resin splinted abutments in the INT and the EXT groups. After 250 N cyclic loading of final prosthesis, the INT group showed more axial displacement than that of the EXT group. Internal tapered conical connection demonstrated a varying amount of axial displacement with tightening torque and cyclic loading. © 2012 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.

  17. Axial compressor gas path design for desensitization of aerodynamic performance and stability to tip clearance

    Science.gov (United States)

    Cevik, Mert

    Tip clearance is the necessary small gap left between the moving rotor tip and stationary shroud of a turbomachine. In a compressor, the pressure driven flow through this gap, called tip clearance flow, has a major and generally detrimental impact on compressor performance (pressure ratio and efficiency) and aerodynamic stability (stall margin). The increase in tip clearance, either temporary during transient engine operations or permanent from wear, leads to a drop in compressor performance and aerodynamic stability which results in a fuel consumption increase and a reduced operating envelope for a gas turbine engine. While much research has looked into increasing compressor performance and stall margin at the design (minimum or nominal) tip clearance, very little attention has been paid for reducing the sensitivity of these parameters to tip clearance size increase. The development of technologies that address this issue will lead to aircraft engines whose performance and operating envelope are more robust to operational demands and wear. The current research is the second phase of a research programme to develop design strategies to reduce the sensitivity of axial compressor performance and aerodynamic stability to tip clearance. The first phase had focused on blade design strategies and had led to the discovery and explanation of two flow features that reduces tip sensitivity, namely increased incoming meridional momentum in the rotor tip region and reduction/elimination of double leakage. Double leakage is the flow that exits one tip clearance and enters the tip clearance of the adjacent blade instead of convecting downstream out of the rotor passage. This flow was shown to be very detrimental to compressor performance and stall margin. Two rotor design strategies involving sweep and tip stagger reduction were proposed and shown by CFD simulations to exploit these features to reduce sensitivity. As the second phase, the objectives of the current research

  18. General overview of the AxialT project: A partnership for low head turbine developments

    International Nuclear Information System (INIS)

    Deschenes, C; Ciocan, G D; Henau, V De; Flemming, F; Qian, R; Huang, J; Koller, M; Vu, T; Naime, F A; Page, M

    2010-01-01

    An overview of the AxialT project is presented. Initiated in 2007 by the Consortium on Hydraulic Machines, the aim of this four years project is to contribute to the study of time-dependent hydraulic phenomena in a propeller turbine. The geometry of the entire turbine is generously shared by all partners. Numerical simulations carried out by all partners are confronted with experimental measurements carried out at the LAMH laboratory in Laval University. A mix of 2D LDA, 3D PIV and unsteady pressure measurements are adapted to yield precise measurements at eight strategic locations within the turbine and for nine operating points. Phase resolved analysis is performed wherever applicable. An illustration of potential analysis accessible with the database is shown for the identification of a vortex in the runner at part load.

  19. Hybrid machining processes perspectives on machining and finishing

    CERN Document Server

    Gupta, Kapil; Laubscher, R F

    2016-01-01

    This book describes various hybrid machining and finishing processes. It gives a critical review of the past work based on them as well as the current trends and research directions. For each hybrid machining process presented, the authors list the method of material removal, machining system, process variables and applications. This book provides a deep understanding of the need, application and mechanism of hybrid machining processes.

  20. Radial loads and axial thrusts on centrifugal pumps

    International Nuclear Information System (INIS)

    Anon.

    1986-01-01

    The proceedings of a seminar organised by the Power Industries Division of the IMechE are presented in this text. Complete contents: Review of parameters influencing hydraulic forces on centrifugal impellers; The effect of fluid forces at various operation conditions on the vibrations of vertical turbine pumps; A review of the pump rotor axial equilibrium problem - some case studies; Dynamic hydraulic loading on a centrifugal pump impeller; Experimental research on axial thrust loads of double suction centrifugal pumps; A comparison of pressure distribution and radial loads on centrifugal pumps; A theoretical and experimental investigation of axial thrusts within a multi-stage centrifugal pump

  1. Measurement for cobalt target activity and its axial distribution

    International Nuclear Information System (INIS)

    Li Xingyuan; Chen Zigen.

    1985-01-01

    Cobalt target activity and its axial distribution are measured in process of producing radioactive isotopes 60 Co by irradiation in HFETR. Cobalt target activity is obtained with measured data at 3.60 m and 4.60 m, relative axial distribution of cobalt target activity is obtained with one at 30 cm, and axial distribution of cobalt target activity(or specific activity) is obtained with both of data. The difference between this specific activity and measured result for 60 Co teletherapy sources in the end is less than +- 5%

  2. Gravitational waves from the axial perturbations of hyperon stars

    International Nuclear Information System (INIS)

    Wen De-Hua; Yan Jing; Liu Xue-Mei

    2012-01-01

    The eigen-frequencies of the axial w-mode oscillations of hyperon stars are examined. It is shown that as the appearance of hyperons softens the equation of state of the super-density matter, the frequency of gravitational waves from the axial w-mode of hyperon star becomes smaller than that of a traditional neutron star at the same stellar mass. Moreover, the eigenfrequencies of hyperon stars also have scaling universality. It is shown that the EURO third-generation gravitational-wave detector has the potential to detect the gravitational-wave signal emitted from the axial w-mode oscillations of a hyperon star. (general)

  3. Axial weak currents in the Wess-Zumino term

    International Nuclear Information System (INIS)

    Fujikawa, Kazuo.

    1985-03-01

    The conventional axial gauging of the Wess-Zumino term leads to the results which do not necessarily agree with the expectations on the basis of quark level Ward-Takahashi identities. This discrepancy arises from the fact that the quark level anomalous identities reflect the short distance structure of QCD, whereas the gauging of the Wess-Zumino term reflects the axial symmetry in the spontaneously broken chiral phase. The low energy theorem for axial weak fields is not sharply defined, in contrast to the case of vector fields where no such complications arise. (author)

  4. Pion Photo- and Electroproduction and the Partially Conserved Axial Current

    International Nuclear Information System (INIS)

    Haberzettl, Helmut

    2000-01-01

    The relevance of the axial current for pion production processes off the nucleon with real or virtual photons is revisited. Employing the hypothesis of a partially conserved axial current (PCAC), it is shown that, when all of the relevant contributions are taken into account, PCAC does not provide any additional constraint for threshold production processes that goes beyond the Goldberger-Treiman relation. In particular, it is shown that pion electroproduction processes at threshold cannot be used to extract any information regarding the weak axial form factor. The relationships found in previous investigations are seen to be an accident of the approximations usually made in this context

  5. The spin of the proton and the axial anomaly

    International Nuclear Information System (INIS)

    Hatsuda, T.; Zahed, I.

    1989-01-01

    We show that a consistent treatment of the abelian axial anomaly in a two-phase model of the proton yields a flavor singlet axial current that is saturated by the anomaly at Q 2 =0 in the chiral limit. This result suggests that at Q 2 =0 the matrix element of the flavor singlet axial current in a polarized proton state is small while the proton spin is still one-half. Modulo the QCD evolution equation, this result is in fair agreement with the recent EMC data. (orig.)

  6. GapBlaster-A Graphical Gap Filler for Prokaryote Genomes.

    Directory of Open Access Journals (Sweden)

    Pablo H C G de Sá

    Full Text Available The advent of NGS (Next Generation Sequencing technologies has resulted in an exponential increase in the number of complete genomes available in biological databases. This advance has allowed the development of several computational tools enabling analyses of large amounts of data in each of the various steps, from processing and quality filtering to gap filling and manual curation. The tools developed for gap closure are very useful as they result in more complete genomes, which will influence downstream analyses of genomic plasticity and comparative genomics. However, the gap filling step remains a challenge for genome assembly, often requiring manual intervention. Here, we present GapBlaster, a graphical application to evaluate and close gaps. GapBlaster was developed via Java programming language. The software uses contigs obtained in the assembly of the genome to perform an alignment against a draft of the genome/scaffold, using BLAST or Mummer to close gaps. Then, all identified alignments of contigs that extend through the gaps in the draft sequence are presented to the user for further evaluation via the GapBlaster graphical interface. GapBlaster presents significant results compared to other similar software and has the advantage of offering a graphical interface for manual curation of the gaps. GapBlaster program, the user guide and the test datasets are freely available at https://sourceforge.net/projects/gapblaster2015/. It requires Sun JDK 8 and Blast or Mummer.

  7. Machining of Machine Elements Made of Polymer Composite Materials

    Science.gov (United States)

    Baurova, N. I.; Makarov, K. A.

    2017-12-01

    The machining of the machine elements that are made of polymer composite materials (PCMs) or are repaired using them is considered. Turning, milling, and drilling are shown to be most widely used among all methods of cutting PCMs. Cutting conditions for the machining of PCMs are presented. The factors that most strongly affect the roughness parameters and the accuracy of cutting PCMs are considered.

  8. The Design Method of Axial Flow Runners Focusing on Axial Flow Velocity Uniformization and Its Application to an Ultra-Small Axial Flow Hydraulic Turbine

    Directory of Open Access Journals (Sweden)

    Yasuyuki Nishi

    2016-01-01

    Full Text Available We proposed a portable and ultra-small axial flow hydraulic turbine that can generate electric power comparatively easily using the low head of open channels such as existing pipe conduits or small rivers. In addition, we proposed a simple design method for axial flow runners in combination with the conventional one-dimensional design method and the design method of axial flow velocity uniformization, with the support of three-dimensional flow analysis. Applying our design method to the runner of an ultra-small axial flow hydraulic turbine, the performance and internal flow of the designed runner were investigated using CFD analysis and experiment (performance test and PIV measurement. As a result, the runners designed with our design method were significantly improved in turbine efficiency compared to the original runner. Specifically, in the experiment, a new design of the runner achieved a turbine efficiency of 0.768. This reason was that the axial component of absolute velocity of the new design of the runner was relatively uniform at the runner outlet in comparison with that of the original runner, and as a result, the negative rotational flow was improved. Thus, the validity of our design method has been verified.

  9. Transitions in axial morphology along the Southeast Indian Ridge

    Science.gov (United States)

    Ma, Ying; Cochran, James R.

    1996-07-01

    Shipboard bathymetric and magnetic profiles across the Southeast Indian Ridge (SEIR) were analyzed in order to examine the nature of along-axis variations in axial morphology at this intermediate spreading rate ridge. Three types of axial morphology are observed along the SEIR: an axial high, a shallow (200-700 m deep) axial valley and a deep (>1000 m deep) axial valley. An axial high is found to the east of the Australian-Antarctic Discordance (AAD) (east of 128°E) and between 82°E and 104°E. A shallow rift valley is found from 104°E to 114°E and from 82°E westward past the Amerstdam/St. Paul hotspot (ASP) to about 30°S, 75°E. Deep rift valleys are found from 114°E to 128°E in the vicinity of the AAD and from the Indian Ocean Triple Junction (IOTJ) at 25°S, 70°E to about 30°S, 75°E. The transition near 30°S occurs in an area of constant zero-age depth and does not appear to result from an increase in mantle temperature. It could be the result of the rapid increase in spreading rate along that portion of the SEIR. The most likely cause of the other transitions in axial morphology is variations in mantle temperature. The transitions between the different types of axial morphology are well defined and occur over a limited distance. Transitions in axial morphology are accompanied by significant changes in ridge flank topographic roughness. The transitions from axial valleys to axial highs are also accompanied by changes in the amplitude of the seafloor magnetic anomalies. Our observations suggest that there are distinct modes rather than a continuum of axial morphology on the SEIR and that there appears to be a "threshold" mechanism for a rapid change between different states of axial morphology. The ASP has only a limited influence on the SEIR. The ridge axis is marked by an axial valley for the entire distance from the IOTJ up to and past the ASP. The ridge axis becomes shallower as the ASP is approached from the northwest but only by about 300 m over

  10. Ligament rupture and unstable burst behaviors of axial flaws in steam generator U-bends

    Energy Technology Data Exchange (ETDEWEB)

    Bahn, Chi Bum, E-mail: bahn@pusan.ac.kr [Pusan National University, 2 Busandaehak-ro 63 beon-gil, Geumjeong-gu, Busan 609-735 (Korea, Republic of); Oh, Young-Jin [KEPCO Engineering & Construction Co. Inc., Seongnam 463-870 (Korea, Republic of); Majumdar, Saurin [Argonne National Laboratory, Lemont, IL 60439 (United States)

    2015-11-15

    Highlights: • Ligament rupture and unstable burst pressure tests were conducted with U-bends. • In general, U-bends showed higher ligament rupture and burst pressures than straight tubes. • U-bend test data was bounded by 90% lower limit of the probabilistic models for straight tubes. • Prediction models for straight tubes could be conservatively applied to U-bends. - Abstract: Incidents of U-bend cracking in steam generator (SG) tubes have been reported, some of which have led to tube rupture. Experimental and analytical modeling efforts to determine the failure criteria of flawed SG U-bends are limited. To evaluate structural integrity of flawed U-bends, ligament rupture and unstable burst pressure tests were conducted on 57 and 152 mm bend radius U-bends with axial electrical discharge machining notches. In general, the ligament rupture and burst pressures of the U-bends were higher than those of straight tubes with similar notches. To quantitatively address the test data scatter issue, probabilistic models were introduced. All ligament rupture and burst pressures of U-bends were bounded by 90% lower limits of the probabilistic models for straight tubes. It was concluded that the prediction models for straight tubes could be applied to U-bends to conservatively evaluate the ligament rupture and burst pressures of U-bends with axial flaws.

  11. Ligament rupture and unstable burst behaviors of axial flaws in steam generator U-bends

    International Nuclear Information System (INIS)

    Bahn, Chi Bum; Oh, Young-Jin; Majumdar, Saurin

    2015-01-01

    Highlights: • Ligament rupture and unstable burst pressure tests were conducted with U-bends. • In general, U-bends showed higher ligament rupture and burst pressures than straight tubes. • U-bend test data was bounded by 90% lower limit of the probabilistic models for straight tubes. • Prediction models for straight tubes could be conservatively applied to U-bends. - Abstract: Incidents of U-bend cracking in steam generator (SG) tubes have been reported, some of which have led to tube rupture. Experimental and analytical modeling efforts to determine the failure criteria of flawed SG U-bends are limited. To evaluate structural integrity of flawed U-bends, ligament rupture and unstable burst pressure tests were conducted on 57 and 152 mm bend radius U-bends with axial electrical discharge machining notches. In general, the ligament rupture and burst pressures of the U-bends were higher than those of straight tubes with similar notches. To quantitatively address the test data scatter issue, probabilistic models were introduced. All ligament rupture and burst pressures of U-bends were bounded by 90% lower limits of the probabilistic models for straight tubes. It was concluded that the prediction models for straight tubes could be applied to U-bends to conservatively evaluate the ligament rupture and burst pressures of U-bends with axial flaws.

  12. EBQ code: Transport of space-charge beams in axially symmetric devices

    Science.gov (United States)

    Paul, A. C.

    1982-11-01

    Such general-purpose space charge codes as EGUN, BATES, WODF, and TRANSPORT do not gracefully accommodate the simulation of relativistic space-charged beams propagating a long distance in axially symmetric devices where a high degree of cancellation has occurred between the self-magnetic and self-electric forces of the beam. The EBQ code was written specifically to follow high current beam particles where space charge is important in long distance flight in axially symmetric machines possessing external electric and magnetic field. EBQ simultaneously tracks all trajectories so as to allow procedures for charge deposition based on inter-ray separations. The orbits are treated in Cartesian geometry (position and momentum) with z as the independent variable. Poisson's equation is solved in cylindrical geometry on an orthogonal rectangular mesh. EBQ can also handle problems involving multiple ion species where the space charge from each must be included. Such problems arise in the design of ion sources where different charge and mass states are present.

  13. EBQ code: transport of space-charge beams in axially symmetric devices

    International Nuclear Information System (INIS)

    Paul, A.C.

    1982-11-01

    Such general-purpose space charge codes as EGUN, BATES, WOLF, and TRANSPORT do not gracefully accommodate the simulation of relativistic space-charged beams propagating a long distance in axially symmetric devices where a high degree of cancellation has occurred between the self-magnetic and self-electric forces of the beam. The EBQ code was written specifically to follow high current beam particles where space charge is important in long distance flight in axially symmetric machines possessing external electric and magnetic field. EBQ simultaneously tracks all trajectories so as to allow procedures for charge deposition based on inter-ray separations. The orbits are treated in Cartesian geometry (position and momentum) with z as the independent variable. Poisson's equation is solved in cylindrical geometry on an orthogonal rectangular mesh. EBQ can also handle problems involving multiple ion species where the space charge from each must be included. Such problems arise in the design of ion sources where different charge and mass states are present

  14. Wide gap, permanent magnet biased magnetic bearing system

    Science.gov (United States)

    Boden, Karl

    1992-01-01

    The unique features and applications of the presented electrical permanent magnetic bearing system essentially result from three facts: (1) the only bearing rotor components are nonlaminated ferromagnetic steel collars or cylinders; (2) all radial and axial forces are transmitted via radial gaps; and (3) large radial bearing gaps can be provided with minimum electric power consumption. The large gaps allow for effective encapsulation and shielding of the rotors at elevated or low temperatures, corrosive or ultra clean atmosphere or vacuum or high pressure environment. Two significant applications are described: (1) a magnetically suspended x ray rotary anode was operated under high vacuum conditions at 100 KV anode potential, 600 C temperature at the rotor collars and speed 18000 rpm with 13 mm radial bearing gap; and (2) an improved Czochralski type crystal growth apparatus using the hot wall method for pulling GaAs single crystals of low dislocation density. Both crystal and crucible are carried and transported by magnetically suspended shafts inside a hermetically sealed housing at 800 C shaft and wall temperature. The radial magnetic bearing gap measures 24 mm.

  15. New Cogging Torque Reduction Methods for Permanent Magnet Machine

    Science.gov (United States)

    Bahrim, F. S.; Sulaiman, E.; Kumar, R.; Jusoh, L. I.

    2017-08-01

    Permanent magnet type motors (PMs) especially permanent magnet synchronous motor (PMSM) are expanding its limbs in industrial application system and widely used in various applications. The key features of this machine include high power and torque density, extending speed range, high efficiency, better dynamic performance and good flux-weakening capability. Nevertheless, high in cogging torque, which may cause noise and vibration, is one of the threat of the machine performance. Therefore, with the aid of 3-D finite element analysis (FEA) and simulation using JMAG Designer, this paper proposed new method for cogging torque reduction. Based on the simulation, methods of combining the skewing with radial pole pairing method and skewing with axial pole pairing method reduces the cogging torque effect up to 71.86% and 65.69% simultaneously.

  16. Aliens and time in the machine age

    Science.gov (United States)

    Brake, Mark; Hook, Neil

    2006-12-01

    The 19th century saw sweeping changes for the development of astrobiology, both in the constituency of empirical science encroaching upon all aspects of life and in the evolution of ideas, with Lyell's Principles of Geology radically raising expectation of the true age of the Earth and the drama of Darwinism questioning biblically literalist accounts of natural history. This paper considers the popular culture spun on the crackling loom of the emergent aspects of astrobiology of the day: Edward Bulwer-Lytton's The Coming Race (1871), which foretold the race of the future, and satirist Samuel Butler's anticipation of machine intelligence, `Darwin Among the Machines', in his Erewhon (1872). Finally, we look at the way Darwin, Huxley and natural selection travelled into space with French astronomer Camille Flammarion's immensely popular Récits de l'infini (Stories of Infinity, 1872), and the social Darwinism of H.G. Wells' The Time Machine (1895) and The War of the Worlds (1898). These works of popular culture presented an effective and inspiring communication of science; their crucial discourse was the reducible gap between the new worlds uncovered by science and exploration and the fantastic strange worlds of the imagination. As such they exemplify a way in which the culture and science of popular astrobiology can be fused.

  17. DESIGN OF GRASS BRIQUETTE MACHINE

    African Journals Online (AJOL)

    user

    E-mail addresses: 1 mike.ajieh@gmail.com, 2 dracigboanugo@yahoo.com, ... machine design was considered for processing biomass of grass origin. The machine operations include pulverization, compaction and extrusion of the briquettes.

  18. New Applications of Learning Machines

    DEFF Research Database (Denmark)

    Larsen, Jan

    * Machine learning framework for sound search * Genre classification * Music separation * MIMO channel estimation and symbol detection......* Machine learning framework for sound search * Genre classification * Music separation * MIMO channel estimation and symbol detection...

  19. Tattoo machines, needles and utilities.

    Science.gov (United States)

    Rosenkilde, Frank

    2015-01-01

    Starting out as a professional tattooist back in 1977 in Copenhagen, Denmark, Frank Rosenkilde has personally experienced the remarkable development of tattoo machines, needles and utilities: all the way from home-made equipment to industrial products of substantially improved quality. Machines can be constructed like the traditional dual-coil and single-coil machines or can be e-coil, rotary and hybrid machines, with the more convenient and precise rotary machines being the recent trend. This development has resulted in disposable needles and utilities. Newer machines are more easily kept clean and protected with foil to prevent crosscontaminations and infections. The machines and the tattooists' knowledge and awareness about prevention of infection have developed hand-in-hand. For decades, Frank Rosenkilde has been collecting tattoo machines. Part of his collection is presented here, supplemented by his personal notes. © 2015 S. Karger AG, Basel.

  20. QCD machines - present and future

    International Nuclear Information System (INIS)

    Christ, N.H.

    1991-01-01

    The present status of the currently working and nearly working dedicated QCD machines is reviewed and proposals for future machines are discussed with particular emphasis on the QCD Teraflop Project in the US. (orig.)