International Nuclear Information System (INIS)
The successful development of ITER and DEMO scenarios requires preparatory activities on devices that are smaller than ITER, sufficiently flexible and capable of investigating the peculiar physics of burning plasma conditions. The aim of the Fusion Advanced Studies Torus (FAST) proposal [2.1] (formerly FT3 [2.2]) is to show that the preparation of ITER scenarios and the development of new expertise for the DEMO design and RD can be effectively implemented on a new facility. FAST will a) operate with deuterium plasmas, thereby avoiding problems associated with tritium, and allow investigation of nonlinear dynamics (which are important for understanding alpha particle behaviour in burning plasmas) by using fast ions accelerated by heating and current drive systems; b) work in a dimensionless parameter range close to that of ITER; c) test technical innovative solutions, such as full-tungsten plasma-facing components and an advanced liquid metal divertor target for the first wall/divertor, directly relevant for ITER and DEMO; d) exploit advanced regimes with a much longer pulse duration than the current diffusion time; e) provide a test bed for ITER and DEMO diagnostics; f) provide an ideal framework for model and numerical code benchmarks, their verification and validation in ITER/ DEMO-relevant plasma conditions
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One of the main FAST (Fusion Advanced Studies Torus) goals is to have a flexible experiment capable to test tools and scenarios for safe and reliable tokamak operation, in order to support ITER and help the final DEMO design. In particular, in this paper, we focus on operation close to a possible border of stability related to low-q operation. To this purpose, a new FAST scenario has then been designed at Ip = 10 MA, BT = 8.5 T, q95 ≈ 2.3. Transport simulations, carried out by using the code JETTO and the first principle transport model GLF23, indicate that, under these conditions, FAST could achieve an equivalent Q ≈ 3.5. FAST will be equipped with a set of internal active coils for feedback control, which will produce magnetic perturbation with toroidal number n = 1 or n = 2. Magnetohydrodynamic (MHD) mode analysis and feedback control simulations performed with the codes MARS, MARS-F, CarMa (both assuming the presence of a perfect conductive wall and using the exact 3D resistive wall structure) show the possibility of the FAST conductive structures to stabilize n = 1 ideal modes. This leaves therefore room for active mitigation of the resistive mode (down to a characteristic time of 1 ms) for safety purposes, i.e., to avoid dangerous MHD-driven plasma disruption, when working close to the machine limits and magnetic and kinetic energy density not far from reactor values
Advances in compact torus research
International Nuclear Information System (INIS)
A compact torus is a low aspect ratio, axisymmetric, closed magnetic field line configuration with no vessel wall or magnetic field coils linking the hole in the plasma toroid. This concept offers reactor advantages such as simplicity, high β, and the possibility of translation. Several methods have been used to generate compact toroids, including plasma guns, high energy particle rings, and field-reversed theta pinches. This document summarizes the results of recent work on compact toroids, presented at the first IAEA Technical Committee Meeting on Compact Torus Research held in Sydney, Australia from 4 to 7 March 1985
Overview of spherical torus studies
International Nuclear Information System (INIS)
Spherical torus is an advance magnetic confinement device for nuclear fusion research, which retains many features of tokamak configuration, such as closed magnetic surfaces and field lines of medium rotational transform, and good plasma confinement. In addition it has low aspect ratio and lower toroidal magnetic field, and it is compact, economical with respect to traditional tokamak. Therefore it has the potential for a nuclear fusion reactor. The engineering, experiment, and theory status as well as challenges in spherical torus research are comprehensively presented
Compact torus studies: Final report
International Nuclear Information System (INIS)
The compact torus (CT) device has been proposed for use in some applications which are of interest in Laboratory programs in the areas of pulsed power and inertial confinement fusion. These applications involve compression and acceleration of CT plasmas. The RACE (Ring Accelerator Experiment) experimental program at Livermore has been initiated to study these applications. The work reported here involves studies of plasma physics and other aspects of these compact torus applications. The studies conducted identify specific problem areas associated with the CT device and examine these areas in some detail. This report contains studies of three particular problem areas of the CT applications. These three areas are: the general nonlinear properties of the CT as a magnetohydrodynamic (MHD) equilibrium, particle simulation of the compression of the CT, with a focus on the non-MHD effects, and nonlinear RF interaction problems in the CT
Studies of accelerated compact toruses
International Nuclear Information System (INIS)
In an earlier publication we considered acceleration of plasma rings (Compact Torus). Several possible accelerator configurations were suggested and the possibility of focusing the accelerated rings was discussed. In this paper we consider one scheme, acceleration of a ring between coaxial electrodes by a B/sub theta/ field as in a coaxial rail-gun. If the electrodes are conical, a ring accelerated towards the apex of the cone undergoes self-similar compression (focusing) during acceleration. Because the allowable acceleration force, F/sub a/ = kappaU/sub m//R where (kappa -2, the accelerating distance for conical electrodes is considerably shortened over that required for coaxial electrodes. In either case, however, since the accelerating flux can expand as the ring moves, most of the accelerating field energy can be converted into kinetic energy of the ring leading to high efficiency
Next Step Spherical Torus Design Studies
International Nuclear Information System (INIS)
Studies are underway to identify and characterize a design point for a Next Step Spherical Torus (NSST) experiment. This would be a ''Proof of Performance'' device which would follow and build upon the successes of the National Spherical Torus Experiment (NSTX) a ''Proof of Principle'' device which has operated at PPPL since 1999. With the Decontamination and Decommissioning (DandD) of the Tokamak Fusion Test Reactor (TFTR) nearly completed, the TFTR test cell and facility will soon be available for a device such as NSST. By utilizing the TFTR test cell, NSST can be constructed for a relatively low cost on a short time scale. In addition, while furthering spherical torus (ST) research, this device could achieve modest fusion power gain for short-pulse lengths, a significant step toward future large burning plasma devices now under discussion in the fusion community. The selected design point is Q=2 at HH=1.4, P subscript ''fusion''=60 MW, 5 second pulse, with R subscript ''0''=1.5 m, A=1.6, I subscript ''p''=10vMA, B subscript ''t''=2.6 T, CS flux=16 weber. Most of the research would be conducted in D-D, with a limited D-T campaign during the last years of the program
International Nuclear Information System (INIS)
Geometrical structure and physical characteristics of a torus are investigated in detail. Newtonian and electromagnetic potentials of the torus are defined at short and long distances. It is shown that torus potential at small distances has attractive oscillator behaviour. Motion of a particle in the torus potential is studied. The inertia tensor of the torus and its dynamics are obtained. Rotating torus whose tip is held fixed by two massless rigid threads and moves in a gravitational field is considered. (author)
International Nuclear Information System (INIS)
FAST is a new machine proposed to support ITER experimental exploitation as well as to anticipate DEMO relevant physics and technology. FAST is aimed at studying, in burning plasma relevant conditions, fast particle physics, plasma operations and plasma wall interaction in an integrated way. FAST has the capability to approach all the ITER scenarios significantly closer than present day experiments by using Deuterium plasmas. The necessity of achieving ITER relevant performance with a moderate cost has led to conceiving a compact Tokamak (R=1.82 m, a= 0.64 m) with high toroidal field (BT up to 8.5 T) and plasma current (Ip up to 8 MA). In order to study fast particle behaviours in conditions similar to those of ITER, the project has been provided with a dominant Ion Cyclotron Resonance Heating System (ICRH; 30 MW on the plasma). Moreover, the experiment foresees the use of 6 MW of Lower Hybrid (LHCD), essentially for plasma control and for non-inductive Current Drive, and of Electron Cyclotron Resonance Heating (ECRH, 4MW) for localized electron heating and plasma control. The ports have been designed to accommodate up to 10 MW of negative beams (NNBI) in the energy range of 0.5-1 MeV. The total power input will be in the 30-40 MW range in the different plasma scenarios with a wall power load comparable with that of ITER (P/R∼22 MW/m). All the ITER scenarios will be studied: from the reference H-mode, with plasma edge and ELMs characteristics similar to the ITER ones (Q up to ≅ 2.5), to a full current drive scenario, lasting around 170 s. The first wall as well as the divertor plates will be of Tungsten in order to ensure reactor relevant operation regimes. The divertor itself is designed to be completely removable by remote handling. This will allow studying (in view of DEMO) the behaviour of innovative divertor concepts, such as those based on liquid Lithium. FAST is capable of operations with very long pulses, up to 170 s, despite that it is a copper machine
Feasibility study for the Spherical Torus Experiment
International Nuclear Information System (INIS)
The design of the Spherical Torus Experiment (STX) is discussed. The physics of the plasma are given in a magnetohydrodynamic model. The structural aspects and instrumentation of the device are described. 19 refs., 103 figs
Advanced tokamak reactors based on the spherical torus (ATR/ST). Preliminary design considerations
Energy Technology Data Exchange (ETDEWEB)
Miller, R.L.; Krakowski, R.A.; Bathke, C.G.; Copenhaver, C.; Schnurr, N.M.; Engelhardt, A.G.; Seed, T.J.; Zubrin, R.M.
1986-06-01
Preliminary design results relating to an advanced magnetic fusion reactor concept based on the high-beta, low-aspect-ratio, spherical-torus tokamak are summarized. The concept includes resistive (demountable) toroidal-field coils, magnetic-divertor impurity control, oscillating-field current drive, and a flowing liquid-metal breeding blanket. Results of parametric tradeoff studies, plasma engineering modeling, fusion-power-core mechanical design, neutronics analyses, and blanket thermalhydraulics studies are described. The approach, models, and interim results described here provide a basis for a more detailed design. Key issues quantified for the spherical-torus reactor center on the need for an efficient drive for this high-current (approx.40 MA) device as well as the economic desirability to increase the net electrical power from the nominal 500-MWe(net) value adopted for the baseline system. Although a direct extension of present tokamak scaling, the stablity and transport of this high-beta (approx.0.3) plasma is a key unknown that is resoluble only by experiment. The spherical torus generally provides a route to improved tokamak reactors as measured by considerably simplified coil technology in a configuration that allows a realistic magnetic divertor design, both leading to increased mass power density and reduced cost.
Advanced tokamak reactors based on the spherical torus (ATR/ST). Preliminary design considerations
International Nuclear Information System (INIS)
Preliminary design results relating to an advanced magnetic fusion reactor concept based on the high-beta, low-aspect-ratio, spherical-torus tokamak are summarized. The concept includes resistive (demountable) toroidal-field coils, magnetic-divertor impurity control, oscillating-field current drive, and a flowing liquid-metal breeding blanket. Results of parametric tradeoff studies, plasma engineering modeling, fusion-power-core mechanical design, neutronics analyses, and blanket thermalhydraulics studies are described. The approach, models, and interim results described here provide a basis for a more detailed design. Key issues quantified for the spherical-torus reactor center on the need for an efficient drive for this high-current (approx.40 MA) device as well as the economic desirability to increase the net electrical power from the nominal 500-MWe(net) value adopted for the baseline system. Although a direct extension of present tokamak scaling, the stablity and transport of this high-beta (approx.0.3) plasma is a key unknown that is resoluble only by experiment. The spherical torus generally provides a route to improved tokamak reactors as measured by considerably simplified coil technology in a configuration that allows a realistic magnetic divertor design, both leading to increased mass power density and reduced cost
International Nuclear Information System (INIS)
This project was undertaken to develop innovative concepts for improving the performance of ELMO Bumpy Torus devices in those aspects of plasma confinement that are particularly relevant to an eventual EBT reactor concept. These include effective magnetic utilization using Andreoletti coils, enhanced confinement using positive ambipolar potentials, and attractive divertor concepts that are compatible with formation and maintenance of ELMO rings. Each of the three major objectives was achieved and, except for the divertor studies, documented for publication and presentation at major scientific meetings. This report provides a brief recapitulation of the major results achieved in the form of a collection of those publications, together with this Introduction
International Nuclear Information System (INIS)
FAST is a new machine proposed to support ITER experimental exploitation as well as to anticipate DEMO relevant physics and technology. FAST is aimed at studying, under burning plasma relevant conditions, fast particle (FP) physics, plasma operations and plasma wall interaction in an integrated way. FAST has the capability to approach all the ITER scenarios significantly closer than the present day experiments using deuterium plasmas. The necessity of achieving ITER relevant performance with a moderate cost has led to conceiving a compact tokamak (R = 1.82 m, a = 0.64 m) with high toroidal field (BT up to 8.5 T) and plasma current (Ip up to 8 MA). In order to study FP behaviours under conditions similar to those of ITER, the project has been provided with a dominant ion cyclotron resonance heating system (ICRH; 30 MW on the plasma). Moreover, the experiment foresees the use of 6 MW of lower hybrid (LHCD), essentially for plasma control and for non-inductive current drive, and of electron cyclotron resonance heating (ECRH, 4 MW) for localized electron heating and plasma control. The ports have been designed to accommodate up to 10 MW of negative neutral beams (NNBI) in the energy range 0.5-1 MeV. The total power input will be in the 30-40 MW range under different plasma scenarios with a wall power load comparable to that of ITER (P/R ∼ 22 MW m-1). All the ITER scenarios will be studied: from the reference H mode, with plasma edge and ELMs characteristics similar to the ITER ones (Q up to ∼1.5), to a full current drive scenario, lasting around 170 s. The first wall (FW) as well as the divertor plates will be of tungsten in order to ensure reactor relevant operation regimes. The divertor itself is designed to be completely removable by remote handling. This will allow us to study (in view of DEMO) the behaviour of innovative divertor concepts, such as those based on liquid lithium. FAST is capable of operating with very long pulses, up to 170 s, despite being a
International Nuclear Information System (INIS)
FAST is the conceptual design for a new machine proposed to support ITER experimental exploitation as well as to anticipate DEMO relevant physics and technology. FAST is aimed at integrated investigations of fast particle physics, plasma operations and plasma wall interaction in burning plasma relevant conditions. In Deuterium plasma operations, FAST has the capability to simultaneously approach relevant dimensionless physical parameters in all the ITER scenarios. The necessity of achieving ITER relevant power densities and performance with moderate cost has led to a compact Tokamak design (R=1.82 m , a= 0.64 m), with a high toroidal field (BT up to 8.5 T) and plasma current (Ip up to 8 MA). In order to study fast particle behaviours with dimensionless parameters similar to ITER, the project is based on a dominant Ion Cyclotron Resonance Heating system (ICRH; 30 MW coupled to the plasma). Moreover, the experiment foresees 6 MW of Lower Hybrid (LH), essentially for plasma control and for non-inductive current drive, and of Electron Cyclotron Resonance Heating (ECRH; 4MW) for localized electron heating and plasma control. Ports have been designed to also accommodate up to 10 MW of negative neutral beam injection (NNBI) in the energy range of 0.5-1 MeV. The total power input is in the 30-40 MW range in the different plasma scenarios, with a wall power load comparable with that of ITER (P/R∼22 MW/m). All ITER scenarios can be studied: starting from the reference H-mode, with plasma edge and ELMs characteristics similar to those of ITER (Q up to ∼ 2.5), and arriving to full non-inductive current drive scenarios lasting ∼ 160 s, Under these conditions, first wall as well as divertor plates will be made of tungsten. The divertor itself is designed to be completely removable by remote handling. This will allow studying, in view of DEMO, the behaviour of innovative divertor concepts, such as those foreseeing the use of liquid lithium. FAST is capable to operate with
Studying uniform thickness II: Transversely nonsimple iterated torus knots
DEFF Research Database (Denmark)
LaFountain, Douglas
2011-01-01
We prove that an iterated torus knot type in the standard contact 3-sphere fails the uniform thickness property (UTP) if and only if it is formed from repeated positive cablings, which is precisely when an iterated torus knot supports the standard contact structure. This is the first complete UTP...
Directory of Open Access Journals (Sweden)
Pumersha Naidoo
2013-11-01
Full Text Available Kupffer and Bessel-Hagen coined the term torus palatinus in 1879 for a benign osseous protuberance arising from the midline of the hard palate. Tori are present in approximately 20% of the population and are occult until adulthood. Recent advances in modern radiology have led to improved evaluation and diagnosis of tori.
ELMO Bumpy Torus Reactor and power plant: conceptual design study
International Nuclear Information System (INIS)
A complete power plant design of a 1200-MWe ELMO Bumpy Torus Reactor (EBTR) is presented. An emphasis is placed on those features that are unique to the EBT confinement concept, with subsystems and balance-of-plant items that are more generic to magnetic fusion being adapted from past, more extensive tokamak reactor designs. Similar to the latter tokamak studies, this conceptual EBTR design also emphasizes the use of conventional or near state-of-the-art engineering technology and materials. An emphasis is also placed on system accessibility, reliability, and maintainability, as these crucial and desirable characteristics relate to the unique high-aspect-ratio configuration of EBTs. Equal and strong emphasis is given to physics, engineering/technology, and costing/economics components of this design effort. Parametric optimizations and sensitivity studies, using cost-of-electricity as an object function, are reported. Based on these results, the direction for future improvement on an already attractive reactor design is identified
ELMO Bumpy Torus fusion-reactor design study
International Nuclear Information System (INIS)
A complete power plant design of a 1200-MWe ELMO Bumpy Torus Reactor (EBTR) is described. Those features that are unique to the EBT confinement concept are emphasized, with subsystems and balance-of-plant items that are generic to magnetic fusion being adopted from past, more extensive tokamak reactor designs. This overview paper stresses the design philosophy and asumptions that led to an economic, 35-m major-radius design that at 1.4 MW/m2 wall loading generates 4000 MWt with a 15% recirculating power fraction
Spherical torus concept as power plants - the ARIES-ST study
International Nuclear Information System (INIS)
Recent experimental achievements and theoretical studies have generated substantial interest in the spherical torus concept. The ARIES-ST study was undertaken as a national US effort to investigate the potential of the spherical tokamak concept as a fusion power plant. This 1000 MWe fusion power plant conceptual design has an aspect ratio of 1.6, a major radius of 3.2 m, a plasma elongation (at 95% flux surface) of 3.4 and triangularity of 0.64. This configuration attains a plasma βT of 50% (which is 90% of theoretical limit). While the plasma current is 28 MA, the almost perfect alignment of bootstrap and equilibrium current density profiles results in a current-drive power of only 28 MW. The on-axis toroidal field of 2.1 T and the peak field at the TF coil of 7.4 T led to 329 MW of Joule losses in the normal-conducting TF system. The power core uses an advanced 'dual-cooled' breeding blanket with flowing PbLi breeder and He-cooled ferritic steel structures that can achieve a thermal conversion efficiency of ∼45%. The ARIES-ST study has highlighted many areas where trade-off among physics and engineering systems are critical in determining the optimum regime of operation for ST power plants
Gordian adjacency for torus knots
Feller, Peter
2013-01-01
A knot K is called Gordian adjacent to a knot L if there exists an unknotting sequence for L containing K. We provide a sufficient condition for Gordian adjacency of torus knots via the study of knots in the thickened torus. We also completely describe Gordian adjacency for torus knots of index 2 and 3 using Levine-Tristram signatures as obstructions to Gordian adjacency. Finally, Gordian adjacency for torus knots is compared to the notion of adjacency for plane curve singularities.
Energy Technology Data Exchange (ETDEWEB)
Cobble, James Allen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2016-06-09
This document summarizes the Bumpy Torus Experiment as a viable fusion reactor concept. Conclusions reached include the following: In 30 years, order-of-magnitude technological advances have occurred in multiple areas of plasma heating and confinement. The ORNL bumpy torus of the 1970s was technology limited. Now that ITER is technology limited, an alternate concept is needed. A device built on such a concept should be current free, CW, modular, have a gentle shutdown, and demonstrable stability. The bumpy torus meets or has the potential to meet all of these criteria. Earlier, stability was not possible due to power limits; it has not been fully tested. It is time to revisit the bumpy-torus concept with a modest new machine.
Numerical study of the Columbia high-beta device: Torus-II
International Nuclear Information System (INIS)
The ionization, heating and subsequent long-time-scale behavior of the helium plasma in the Columbia fusion device, Torus-II, is studied. The purpose of this work is to perform numerical simulations while maintaining a high level of interaction with experimentalists. The device is operated as a toroidal z-pinch to prepare the gas for heating. This ionization of helium is studied using a zero-dimensional, two-fluid code. It is essentially an energy balance calculation that follows the development of the various charge states of the helium and any impurities (primarily silicon and oxygen) that are present. The code is an atomic physics model of Torus-II. In addition to ionization, we include three-body and radiative recombination processes
Unified Ideal Stability Limits for Advanced Tokamak and Spherical Torus Plasmas
International Nuclear Information System (INIS)
Ideal magnetohydrodynamic stability limits of shaped tokamak plasmas with high bootstrap fraction are systematically determined as a function of plasma aspect ratio. For plasmas with and without wall stabilization of external kink modes, the computed limits are well described by distinct and nearly invariant values of a normalized beta parameter utilizing the total magnetic field energy density inside the plasma. Stability limit data from the low aspect ratio National Spherical Torus Experiment is compared to these theoretical limits and indicates that ideal nonrotating plasma no-wall beta limits have been exceeded in regimes with sufficiently high cylindrical safety factor. These results could impact the choice of aspect ratio in future fusion power plants
Valluri, Monica; Merritt, David
1999-01-01
The maximally compact representation of a regular orbit is in terms of its action-angle variables. Computing the map between a trajectory's Cartesian coordinates and its action-angle variables is called torus construction. This article reviews various approaches to torus construction and their application to galactic dynamics.
Prakash Bahadur Thapa; Rudra Prasad Marasini; Shrawan Kumar Thapa; Nabeesman Singh Pradhan; Shreekrishna Giri
2016-01-01
Background & Objectives: Various methods of immobilization have been recommended for the treatment of torus fracture of distal radius in children. The purpose of this study is to determine if soft bandage is as effective and safe as below elbow circumferential casts in the treatment of torus fracture of the distal radius in the children.Materials & Methods: Children from 4 to 14 years of age, who presented to emergency and outpatient department of orthopaedics and trauma at National A...
A study on conceptual design of tritium production fusion reactor based on spherical torus
International Nuclear Information System (INIS)
Conceptual design of an advanced tritium production reactor based on spherical torus (ST), which is an intermediate application of fusion energy, is presented. Different from traditional Tokamak tritium production reactor design, advanced plasma physics performance and compact structural characteristics of ST are used to minimize tritium leakage and to maximize tritium breeding ratio with arrangement of tritium production blankets as possible as it can do within vacuum vessel in order to produce certain amount of excess tritium except self-sufficient plasma core, corresponding plant availability 40% or more. Based on 2D neutronics calculation, preliminary conceptual design of ST-TPR is presented. Based on systematical analysis, design risk, uncertainty and backup are introduced generally for the backgrounds of next detailed conceptual design. (authors)
Studying uniform thickness II: Transversely non-simple iterated torus knots
LaFountain, Douglas J.
2009-01-01
We prove that an iterated torus knot type fails the uniform thickness property (UTP) if and only if all of its iterations are positive cablings, which is precisely when an iterated torus knot type supports the standard contact structure. We also show that all iterated torus knots that fail the UTP support cabling knot types that are transversely non-simple.
Theoretical studies of Elmo Bumpy Torus. Annual report
International Nuclear Information System (INIS)
The work was divided into six basic areas. Modeling studies compared neoclassical and Fokker-Planck analyses of the core plasma electrons with EBT-S data. Ion physics studies treated propagation and absorption of ion cyclotron waves along with investigation of the effect of wave absorption and instabilities on the ion distribution function. Parametric instability calculations identified processes and thresholds for nonlinear electron cyclotron resonance (ECR) wave absorption. Ring physics studies considered not only energetics and spatial effects, but also scaling and startup scenarios, along with the attendant microwave power requirements. Radio frequency (RF) control studies considered the possibility of influencing transport by wave absorption; related studies produced the important predictions of RF stabilization of interchange modes, without ponderomotive effects. Finally, microwave deposition studies considered the geometric aspects of propagation and absorption of microwaves in a real EBT cavity system
Theoretical studies of Elmo Bumpy Torus. Annual report
International Nuclear Information System (INIS)
The work was divided into four basic areas. Studies of the effect of waves on stability and transport considered the possibility of using radio frequency waves to stabilize interchange modes, as well as the general problem of influencing plasma transport by wave absorption. Studies related to wave heating of plasmas considered nonlinear effects such as mode conversion and parametric absorption, along with studies of the structure of ion cyclotron waves in a strongly bumpy geometry. Ring physics studies added nonadiabaticity and whistler instabilities to the model, producing a fairly realistic picture of energy balance, power requirements, and scaling for hot electron rings. Finally, studies analyzing EBT transport data were performed, with emphasis on testing various hypotheses for apparent anomalies in the EBT
Do gender and torus mandibularis affect mandibular cortical index? A cross-sectional study
Directory of Open Access Journals (Sweden)
Hatipoğlu Müjgan
2007-10-01
Full Text Available Abstract Background The interactions between torus and several factors such as age, gender, and dental status have not been studied comprehensively. The purpose of this study was to determine the effect of gender on the mandibular cortical index (MCI and to investigate a possible association between torus mandibularis (TM and MCI. Methods The study consisted of 189 consecutive patients referred to Department of Oral Diagnosis and Radiology of Hacettepe University within 30 workdays. Patients who did not have systemic disorders affecting bone density were included; and the age, gender, dental status and existing TM of the patients were recorded. Morphology of the mandibular inferior cortex was determined according to Klemitti's classification on panoramic radiographs. Results MCI was affected by age and gender (P P > 0.05. Conclusion In the study population, MCI was affected by age and gender. As age increased, semilunar defects could be seen on the cortex of the mandible and MCI values increased. Women appeared to have higher MCI values than men.
Arithmetic of Double Torus Quotients and the Distribution of Periodic Torus Orbits
Khayutin, Ilya
2015-01-01
We describe new arithmetic invariants for pairs of torus orbits on inner forms of PGLn and SLn over number fields. These invariants are constructed by studying the double quotient of a linear algebraic group by a maximal torus. Using the new invariants we significantly strengthen results towards the equidistribution of packets of periodic torus orbits on higher rank S-arithmetic quotients. Packets of periodic torus orbits are natural collections of torus orbits coming from a single adelic tor...
Two-Dimensional Transport Studies for the Composition and Structure of the Io Plasma Torus
Smyth, William H.
2004-01-01
Research efforts in the second quarter have been focused upon a preliminary exploration of the likely impact of Europs's local atmospheres and neutral clouds on the plasma torus and the initiation of an assessment of the basic nature of the radial structure of the electron density in the plasma torus during the JO encounter of the Galileo spacecraft with Jupiter.
Spherical Torus Center Stack Design
Energy Technology Data Exchange (ETDEWEB)
C. Neumeyer; P. Heitzenroeder; C. Kessel; M. Ono; M. Peng; J. Schmidt; R. Woolley; I. Zatz
2002-01-18
The low aspect ratio spherical torus (ST) configuration requires that the center stack design be optimized within a limited available space, using materials within their established allowables. This paper presents center stack design methods developed by the National Spherical Torus Experiment (NSTX) Project Team during the initial design of NSTX, and more recently for studies of a possible next-step ST (NSST) device.
Spectroscopic study of turbulent heating in the high beta tokamak - Torus II
International Nuclear Information System (INIS)
Visible spectroscopy, involving line profile and line intensity measurements, was used to study the turbulent heating of the rectangular cross-section high-beta tokamak Torus II. The spectroscopy was done in the visible wave-length region using a six channel polychrometer having 0.2 A resolution, which is capable of radial scans of the plasma. The plasma, obtained by ionizing helium, is heated by poloidal skin currents, induced by a rapid (tau/sub R/ approx. = 1.7 μsec) change of the toroidal magnetic field either parallel or anti-parallel to the initial toroidal bias magnetic field, which converts a cold toroidal Z-pinch plasma into a hot tokamak plasma
Equivariant classification of 2-torus manifolds
Lü, Zhi; Masuda, Mikiya
2008-01-01
A 2-torus manifold is a closed smooth manifold of dimension $n$ with an effective action of a 2-torus group $(\\Z_2)^n$ of rank $n$, and it is said to be locally standard if it is locally isomorphic to a faithful representation of $(\\Z_2)^n$ on $\\R^n$. This paper studies the equivariant classification of locally standard 2-torus manifolds.
Energy Technology Data Exchange (ETDEWEB)
1976-05-01
Recently identified pool swell loads have been the subject of detailed studies by the General Electric Company (GE) acting on behalf of the Mark I Owners Group. This work has been done on a generic basis with plant unique considerations being addressed by grouping the plants or actually performing plant unique analysis of a particular component. Similar work has been done to evaluate the torus support systems and external piping attached to the torus. In addition, at the suggestion of the NRC, each utility with an operating plant plans to conduct a plant unique analysis of the torus support system and external piping attached to the torus. The purpose of the document presented is to describe what is being planned as a minimum for these plant unique analyses. The methods of analysis and the loadings which will be used are described briefly. A description is presented of the evaluation criteria which will be used to determine if a plant unique action plan need be developed and discussed with the NRC as a basis for continued operation during the long term program.
Directory of Open Access Journals (Sweden)
Prakash Bahadur Thapa
2016-01-01
Full Text Available Background & Objectives: Various methods of immobilization have been recommended for the treatment of torus fracture of distal radius in children. The purpose of this study is to determine if soft bandage is as effective and safe as below elbow circumferential casts in the treatment of torus fracture of the distal radius in the children.Materials & Methods: Children from 4 to 14 years of age, who presented to emergency and outpatient department of orthopaedics and trauma at National Academy of Medical Sciences with an isolated torus fracture of distal radius, were randomized and treated with either soft bandage or below-elbow plaster cast by the same investigators. Patients with associated neurovascular injuries, bilateral torus fractures, concomitant physeal injuries and associated musculoskeletal injuries were excluded. The patients were followed up at weekly interval for 4 weeks and analyzed with VAS, ROM and outcome questionnaire and data were analyzed by using SPSS 18.Results: Among the 114 patients analyzed, 57 patients were kept in soft bandage group and 57 in below-elbow cast group. The mean age in soft bandage group was 8.29 year and the mean age in below-elbow cast group was 8.55 years. There was no significant difference between the two groups with regard to patient demographics, initial fracture characteristics and mechanism of injury.Conclusion: Treatment of distal radius torus fracture with soft bandage is a cost-effective and safe in the children below 14 years of age. These minor fractures are stable and not subject to the risks of late displacement which can be very effectively treated symptomatically to provide pain relief by using soft bandage only and educating the parents about the nature of this paediatrics fracture.Journal of College of Medical Sciences-Nepal, Vol.11(4 2015: 3-8
Principal noncommutative torus bundles
DEFF Research Database (Denmark)
Echterhoff, Siegfried; Nest, Ryszard; Oyono-Oyono, Herve
2008-01-01
of bivariant K-theory (denoted RKK-theory) due to Kasparov. Using earlier results of Echterhoff and Williams, we shall give a complete classification of principal non-commutative torus bundles up to equivariant Morita equivalence. We then study these bundles as topological fibrations (forgetting the...
Spectroscopic diagnostics for liquid lithium divertor studies on National Spherical Torus Experiment
International Nuclear Information System (INIS)
The use of lithium-coated plasma facing components for plasma density control is studied in the National Spherical Torus Experiment (NSTX). A recently installed liquid lithium divertor (LLD) module has a porous molybdenum surface, separated by a stainless steel liner from a heated copper substrate. Lithium is deposited on the LLD from two evaporators. Two new spectroscopic diagnostics are installed to study the plasma surface interactions on the LLD: (1) A 20-element absolute extreme ultraviolet (AXUV) diode array with a 6 nm bandpass filter centered at 121.6 nm (the Lyman-α transition) for spatially resolved divertor recycling rate measurements in the highly reflective LLD environment, and (2) an ultraviolet-visible-near infrared R=0.67 m imaging Czerny-Turner spectrometer for spatially resolved divertor D I, Li I-II, C I-IV, Mo I, D2, LiD, CD emission and ion temperature on and around the LLD module. The use of photometrically calibrated measurements together with atomic physics factors enables studies of recycling and impurity particle fluxes as functions of LLD temperature, ion flux, and divertor geometry.
Comparative study of the electron density profiles in the compact torus plasma merging experiments
International Nuclear Information System (INIS)
Following two previous papers on the comparative studies of the electron density distributions for a single compact torus (CT) and a spherical tokamak (ST), and for the a single ST and a merged ST, a comparative study on the dynamics of the electron density profile and after the CT and ST plasma merging process was performed. The sharpness of the peak in the electron density profile around the mid-plane just after the merging of CT with a low safety factor (q value) such as RFP or spheromak is found to be related to the speed of the magnetic axis during the plasma merging process. It is also found that the electron density gradient near the plasma edge in a high q ST is larger than that of a low q CT. High q ST is found to be provided with the magnetic structure which is able to sustain a large thermal pressure by a strong j x B force. Despite these differences in the electron density profile between CT and ST during merging, the confinement characteristics evaluated from the number of electrons confined within the magnetic separatrix after the completion of the merging is almost similar between in the merging CT and in the merging ST. For all configurations, the electron density profiles after the completion of the merging are analogous to those of the corresponding single configuration produced without the merging process. (author)
Prevalence and morphological variability of torus palatanus and torus mandibularis
Zlatanovska, Katerina; Zarkova, Julija; Radeska, Ana; Papakoca, Kiro; Dimova, Cena
2014-01-01
Background: The oral tori are non-pathological and benign exostosis of the cortical and limited amount of bone marrow, covered with a thin and poorly vascularized mucosa. The purpose of this study was to determine the prevalence of torus palatanus (TP) and torus mandibularis (TM) and to define morphological variability in relation to age and gender in the population of Shtip region, Macedonia FYR. Methods and materials: The study comprised of 467 patients, 242 females and 225 males, from 2...
Mouhot, Clément; Neumann, Lukas
2006-01-01
For a general class of linear collisional kinetic models in the torus, including in particular the linearized Boltzmann equation for hard spheres, the linearized Landau equation with hard and moderately soft potentials and the semi-classical linearized fermionic and bosonic relaxation models, we prove explicit coercivity estimates on the associated integro-differential operator for some modified Sobolev norms. We deduce existence of classical solutions near equilibrium for the full non-linear...
Fusion/transmutation reactor studies based on the spherical torus concept
International Nuclear Information System (INIS)
The paper presents a conceptual design for a compact fusion/transmutation experimental reactor based on the spherical torus concept, CFER-ST. A set of plasma parameters suitable for the nuclear waste transmutation blanket are given. The transmutation neutronics, integer structure, thermo-hydraulics, liquid curtain wall and magnet shield design, etc., for two types of minor actinide transmutation blankets, namely the lead-bismuth eutectic cooled blanket and the FLiBe eutectic self-cooled blanket, along with the relevant calculation results, are presented. The preliminary results show that the proposed fusion/transmutation system and the relevant parameters can meet the design goals
Two-Dimensional Transport Studies for the Composition and Structure of the Io Plasma Torus
Smyth, William H.
2003-01-01
The overall objective of this project is to investigate the roles of local and spatially extended plasma sources created by Io, plasma torus chemistry, and plasma convective and diffusive transport in producing the long-lived S(+), S(++) and O(+) radial ribbon structures of the plasma torus, their System III longitude and local-time asymmetries, their energy sources and their possible time variability. To accomplish this objective, two-dimensional [radial (L) and System III longitude] plasma transport equations for the flux-tube plasma content and energy content will be solved that include the convective motions for both the east-west electric field and co-rotational velocity-lag profile near Io s orbit, radial diffusion, and the spacetime dependent flux-tube production and loss created by both neutral-plasma and plasma-ion reaction chemistry in the plasma torus. For neutral-plasma chemistry, the project will for the first time undertake the calculation of realistic three-dimensional, spatially-extended, and time-varying contributions to the flux-tube ion-production and loss that are produced by Io's corona and extended neutral clouds. The unknown two-dimensional spatial nature of diffusion in the plasma transport will be isolated and better defined in the investigation by the collective consideration of the foregoing different physical processes. For energy transport, the energy flow from hot pickup ions (and a new electron source) to thermal ions and electrons will be included in investigating the System III longitude and local-time temperature asymmetries in the plasma torus. The research is central to the scope of the NASA Sun-Earth Connection Roadmap in Quest II Campaign 4 "Comparative Planetary Space Environments" by addressing key questions for understanding the magnetosphere of planets with high rotation rates and large internal plasma sources and, in addition, is of considerable importance to the NASA Solar System Exploration Science Theme. In this regard
Modeling the Europa plasma torus
Schreier, Ron; Eviatar, Aharon; Vasyliunas, Vytenis M.; Richardson, John D.
1993-01-01
The existence of a torus of plasma generated by sputtering from Jupiter's satellite Europa has long been suspected but never yet convincingly demonstrated. Temperature profiles from Voyager plasma observations indicate the presence of hot, possibly freshly picked-up ions in the general vicinity of the orbit of Europa, which may be interpreted as evidence for a local plasma torus. Studies of ion partitioning in the outer regions of the Io torus reveal that the oxygen to sulfur mixing ratio varies with radial distance; this may indicates that oxygen-rich matter is injected from a non-Io source, most probably Europa. We have constructed a quantitative model of a plasma torus near the orbit of Europa which takes into account plasma input from the Io torus, sputtering from the surface of Europa, a great number of ionization and charge exchange processes, and plasma loss by diffusive transport. When the transport time is chosen so that the model's total number density in consistent with the observed total plasma density, the contribution from Europa is found to be significant although not dominant. The model predicts in detail the ion composition, charge states, and the relative fractions of hot Europa-generated and (presumed) cold Io-generated ions. The results are generally consistent with observations from Voyager and can in principle (subject to limitations of data coverage) be confirmed in more detail by Ulysses.
Renormalization on noncommutative torus
D'Ascanio, D; Vassilevich, D V
2016-01-01
We study a self-interacting scalar $\\varphi^4$ theory on the $d$-dimensional noncommutative torus. We determine, for the particular cases $d=2$ and $d=4$, the nonlocal counterterms required by one-loop renormalization. We discuss higher loops in two dimensions and two-loop contributions to the self-energy in four dimensions. Our analysis points towards the absence of any problems related to the UV/IR mixing and thus to renormalizability of the theory. However, we find another potentially troubling phenomenon which is a wild behavior of the two-point amplitude as a function of the noncommutativity matrix $\\theta$.
Renormalization on noncommutative torus
Energy Technology Data Exchange (ETDEWEB)
D' Ascanio, D.; Pisani, P. [Universidad Nacional de La Plata, Instituto de Fisica La Plata-CONICET, La Plata (Argentina); Vassilevich, D.V. [Universidade Federal do ABC, CMCC, Santo Andre, SP (Brazil); Tomsk State University, Department of Physics, Tomsk (Russian Federation)
2016-04-15
We study a self-interacting scalar φ{sup 4} theory on the d-dimensional noncommutative torus. We determine, for the particular cases d = 2 and d = 4, the counterterms required by one-loop renormalization. We discuss higher loops in two dimensions and two-loop contributions to the self-energy in four dimensions. Our analysis points toward the absence of any problems related to the ultraviolet/infrared mixing and thus to renormalizability of the theory. However, we find another potentially troubling phenomenon which is a wild behavior of the two-point amplitude as a function of the noncommutativity matrix θ. (orig.)
Noncommutative principal torus bundles via parametrised strict deformation quantization
Hannabuss, Keith; Mathai, Varghese
2009-01-01
In this paper, we initiate the study of a parametrised version of Rieffel's strict deformation quantization. We apply it to give a classification of noncommutative principal torus bundles, in terms of parametrised strict deformation quantization of ordinary principal torus bundles. The paper also contains a putative definition of noncommutative non-principal torus bundles.
Classification of spin structures on the noncommutative n-torus
Venselaar, Jan Jitse
2010-01-01
We classify spin structures on the noncommutative torus, and find that the noncommutative n-torus has 2^n spin structures, corresponding to isospectral deformations of spin structures on the commutative n-torus. For n>3 the classification depends on Connes' spin manifold theorem. In addition, we study unitary equivalences of these spin structures.
Self-mapping degrees of torus bundles and torus semi-bundles
Sun, Hongbin; Wang, Shicheng; Wu, Jianchun
2010-01-01
Each closed oriented 3-manifold $M$ is naturally associated with a set of integers $D(M)$, the degrees of all self-maps on $M$. $D(M)$ is determined for each torus bundle and torus semi-bundle $M$. The structure of torus semi-bundle is studied in detail. The paper is a part of a project to determine $D(M)$ for all 3-manifolds in Thurston's picture.
Study of plasma confinement in ELMO Bumpy Torus with a heavy-ion beam probe
International Nuclear Information System (INIS)
Plasma confinement in ELMO Bumpy Torus (EBT) is generally strongly dependent on an ambipolar electric field. Spatially resolved measurements of the resulting electric space potential phi/sub sp/ have been made in a single plasma cross section by the heavy-ion beam probe. This diagnostic injects a 4-60-keV beam of (usually) Cs+ ions into the plasma. Measurement of the energy of Cs2+ secondary ions leaving the plasma gives a continuous monitor of the local space potential. In addition, the total detected Cs2+ ion current is proportional to the product of the local electron density and the ionization rate, which, in turn, is a function of the electron temperature. This signal, nf(T/sub e/), is sensitive to all three electron distributions found in EBT - those of the cold surface plasma, the warm core plasma, and the hot electron ring
Energy Technology Data Exchange (ETDEWEB)
Mazzucato, E.; Bell, R. E.; Ethier, S.; Hosea, J. C.; Kaye, S. M.; LeBlanc, B. P.; Lee, W. W.; Ryan, P. M.; Smith, D. R.; Wang, W. X.; Wilson, J. R.
2009-03-26
Various theories and numerical simulations support the conjecture that the ubiquitous problem of anomalous electron transport in tokamaks may arise from a short-scale turbulence driven by the electron temperature gradient. To check whether this turbulence is present in plasmas of the National Spherical Torus Experiment (NSTX), measurements of turbulent fluctuations were performed with coherent scattering of electromagnetic waves. Results from plasmas heated by high harmonic fast waves (HHFW) show the existence of density fluctuations in the range of wave numbers k⊥ρe=0.1-0.4, corresponding to a turbulence scale length of the order of the collisionless skin depth. Experimental observations and agreement with numerical results from the linear gyro-kinetic GS2 code indicate that the observed turbulence is driven by the electron temperature gradient. These turbulent fluctuations were not observed at the location of an internal transport barrier driven by a negative magnetic shear.
International Nuclear Information System (INIS)
We present a direct connection between torus knots and Hopfions by finding stable and static solutions of the extended Faddeev–Skyrme model with a ferromagnetic potential term. (P,Q)-torus knots consisting of |Q| sine-Gordon kink strings twisted P/Q times into the poloidal cycle along the toroidal cycle on a toroidal domain wall carry the Hopf charge PQ, which demonstrates that Hopfions can be further classified according to torus knot type
International Nuclear Information System (INIS)
One of the major maintenance operations anticipated for fusion reactors of the Tokamak configuration is remote removal and replacement of torus sectors. This operation will be difficult due to the massive nature of the sector (375 tonnes), and also due to the precision with which it must be positioned within the fixed structure. The same problem, only to a lesser degree, applies to sub-components of the sector such as the limiter blades, shielding, test assemblies, etc. General and specific design requirements have been generated and trade studies conducted on reactor interfacing details as well as handling machine concepts. On the basis of the design requirements and trade studies, a perferred concept for the sector handling machine was developed. In addition, a similar machine was developed for handling the intermediate sized sector sub-components. While most operations will be performed by special purpose machines such as described above, there is a need for a versatile, relatively high capacity mobile system. A concept suitable for this mobile application was also developed as part of these studies. The general conclusion, to the extent these studies have been completed, was that special single-purpose machines will be required to perform the operations requiring high load capacity and handling precision. The machine concepts developed were felt to be within the state-of-the-art, and will make extensive use of commercially available components. The most serious problem was felt to be development of simple methods to obtain the required precision in positioning massive objects such as the torus sector
Energy Technology Data Exchange (ETDEWEB)
Flohr, Michael [Physikalisches Institut, University of Bonn, Nussallee 12, D-53115 Bonn (Germany); Gaberdiel, Matthias R [Institut fuer Theoretische Physik, ETH Zuerich, ETH-Hoenggerberg, 8093 Zurich (Switzerland)
2006-02-24
For the example of the logarithmic triplet theory at c = -2, the chiral vacuum torus amplitudes are analysed. It is found that the space of these torus amplitudes is spanned by the characters of the irreducible representations, as well as a function that can be associated with the logarithmic extension of the vacuum representation. A few implications and generalizations of this result are discussed.
International Nuclear Information System (INIS)
A plasma based, deuterium and tritium (DT) fueled, volumetric 14 MeV neutron source (VNS) has been considered as a possible facility to support the development of the demonstration fusion power reactor (DEMO). It can be used to test and develop necessary fusion blanket and divertor components and provide sufficient database, particularly on the reliability of nuclear components necessary for DEMO. The VNS device can be complement to ITER by reducing the cost and risk in the development of DEMO. A low cost, scientifically attractive, and technologically feasible volumetric neutron source based on the spherical torus (ST) concept has been conceived. The ST-VNS, which has a major radius of 1.07 m, aspect ratio 1.4, and plasma elongation three, can produce a neutron wall loading from 0.5 to 5 MW m-2 at the outboard test section with a modest fusion power level from 38 to 380 MW. It can be used to test necessary nuclear technologies for fusion power reactor and develop fusion core components include divertor, first wall, and power blanket. Using staged operation leading to high neutron wall loading and optimistic availability, a neutron fluence of more than 30 MW year m-2 is obtainable within 20 years of operation. This will permit the assessments of lifetime and reliability of promising fusion core components in a reactor relevant environment. A full scale demonstration of power reactor fusion core components is also made possible because of the high neutron wall loading capability. Tritium breeding in such a full scale demonstration can be very useful to ensure the self-sufficiency of fuel cycle for a candidate power blanket concept
International Nuclear Information System (INIS)
The Madison Symmetric Torus (MST) is the newest and largest reversed field pinch presently in operation. It incorporates a number of design features that set it apart from other pinches, including the use of the conducting shell as both a vacuum vessel and single-turn toroidal field coil. Specially insulated voltage gaps are exposed to the plasma. Magnetic field errors at these gaps as well as at the various diagnostic and pumping ports are minimized through a variety of techniques. The physics goals of MST include study of the effect of large plasma size on confinement and the investigation, in detail, of RFP turbulence, dynamo and transport. Details of the design and initial operation of the device are presented
Advanced drilling systems study.
Energy Technology Data Exchange (ETDEWEB)
Pierce, Kenneth G.; Livesay, Billy Joe; Finger, John Travis (Livesay Consultants, Encintas, CA)
1996-05-01
This report documents the results of a study of advanced drilling concepts conducted jointly for the Natural Gas Technology Branch and the Geothermal Division of the U.S. Department of Energy. A number of alternative rock cutting concepts and drilling systems are examined. The systems cover the range from current technology, through ongoing efforts in drilling research, to highly speculative concepts. Cutting mechanisms that induce stress mechanically, hydraulically, and thermally are included. All functions necessary to drill and case a well are considered. Capital and operating costs are estimated and performance requirements, based on comparisons of the costs for alternative systems to conventional drilling technology, are developed. A number of problems common to several alternatives and to current technology are identified and discussed.
Energy Technology Data Exchange (ETDEWEB)
Scotti, F.; Soukhanovskii, V. A. [Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)
2015-12-15
A two-channel spectral imaging system based on a charge injection device radiation-hardened intensified camera was built for studies of plasma-surface interactions on divertor plasma facing components in the National Spherical Torus Experiment Upgrade (NSTX-U) tokamak. By means of commercially available mechanically referenced optical components, the two-wavelength setup images the light from the plasma, relayed by a fiber optic bundle, at two different wavelengths side-by-side on the same detector. Remotely controlled filter wheels are used for narrow bandpass and neutral density filters on each optical path allowing for simultaneous imaging of emission at wavelengths differing in brightness up to 3 orders of magnitude. Applications on NSTX-U will include the measurement of impurity influxes in the lower divertor strike point region and the imaging of plasma-material interaction on the head of the surface analysis probe MAPP (Material Analysis and Particle Probe). The diagnostic setup and initial results from its application on the lithium tokamak experiment are presented.
Scotti, F; Soukhanovskii, V A
2015-12-01
A two-channel spectral imaging system based on a charge injection device radiation-hardened intensified camera was built for studies of plasma-surface interactions on divertor plasma facing components in the National Spherical Torus Experiment Upgrade (NSTX-U) tokamak. By means of commercially available mechanically referenced optical components, the two-wavelength setup images the light from the plasma, relayed by a fiber optic bundle, at two different wavelengths side-by-side on the same detector. Remotely controlled filter wheels are used for narrow bandpass and neutral density filters on each optical path allowing for simultaneous imaging of emission at wavelengths differing in brightness up to 3 orders of magnitude. Applications on NSTX-U will include the measurement of impurity influxes in the lower divertor strike point region and the imaging of plasma-material interaction on the head of the surface analysis probe MAPP (Material Analysis and Particle Probe). The diagnostic setup and initial results from its application on the lithium tokamak experiment are presented. PMID:26724002
International Nuclear Information System (INIS)
With the first injection of neutral beams into the National Spherical Torus Experiment (NSTX)[Ono, et al., Nucl. Fusion 40 (2000) 557] a broad spectrum of fluctuations consisting of nearly equally spaced peaks in the frequency range from about 0.2 to 1.2 times the ion cyclotron frequency was observed. The frequencies scale with toroidal field and plasma density consistently with Alfvin waves. From these and other observations, the modes have been identified as Compressional Alfvin Eigenmodes (CAE). It has also recently been found that the ratio of the measured ion and electron temperatures in NSTX during neutral-beam heating is anomalously high[Bell, Bull. Am. Phys. Soc. 46 (2001) 206]. To explain the anomaly in the ratio of ion to electron temperature, it has been suggested that the CAE, driven by the beam ions, stochastically heat the thermal ions[Gates, et al., Phys. Rev. Lett. 87 (2001) 205003]. In this paper, it is shown through studies of the power balance that stochastic heating of the thermal ions by the observed CAE alone is not solely responsible for the anomaly in the ion to electron temperature ratio
International Nuclear Information System (INIS)
With the first injection of neutral beams into the National Spherical Torus Experiment (NSTX) [Ono, et al., Nucl. Fusion 40 (2000) 557] a broad spectrum of fluctuations consisting of nearly equally spaced peaks in the frequency range from about 0.2 to 1.2 times the ion cyclotron frequency was observed. The frequencies scale with toroidal field and plasma density consistently with Alfvin waves. From these and other observations, the modes have been identified as Compressional Alfvin Eigenmodes (CAE). It has also recently been found that the ratio of the measured ion and electron temperatures in NSTX during neutral-beam heating is anomalously high [Bell, Bull. Am. Phys. Soc. 46 (2001) 206]. To explain the anomaly in the ratio of ion to electron temperature, it has been suggested that the CAE, driven by the beam ions, stochastically heat the thermal ions [Gates, et al., Phys. Rev. Lett. 87 (2001) 205003]. In this paper, it is shown through studies of the power balance that stochastic heating of the thermal ions by the observed CAE alone is not solely responsible for the anomaly in the ion to electron temperature ratio
International Nuclear Information System (INIS)
With the first injection of neutral beams into the National Spherical Torus Experiment (NSTX) [Ono et al., Nucl. Fusion 40, 557 (2000)], a broad spectrum of fluctuations consisting of nearly equally spaced peaks in the frequency range from about 0.2 to 1.2 times the ion cyclotron frequency was observed. The frequencies scale with toroidal field and plasma density consistently with Alfven waves. From these and other observations, the modes have been identified as compressional Alfven eigenmodes (CAE). It has also recently been found that the ratio of the measured ion and electron temperatures in NSTX during neutral beam heating is anomalously high [Bell, Bull. Am. Phys. Soc. 46, 206 (2001)]. To explain the anomaly in the ratio of ion to electron temperature, it has been suggested that the CAE, driven by the beam ions, stochastically heat the thermal ions [Gates et al., Phys. Rev. Lett. 87, 205003 (2001)]. In this paper it is shown through studies of the power balance that stochastic heating of the thermal ions by the observed CAE alone is not solely responsible for the anomaly in the ion to electron temperature ratio
TEDIT, a computer code for studying the time evolution of drift instabilities in a torus
International Nuclear Information System (INIS)
TEDIT is an initial-value program that calculates the time evolution of drift instabilities in a toroidal plasma with shear and in a slab-geometry approximation. The electron and ion kinetic equations are advanced in time, with the electrostatic potential phi and vector potential A/sub parallel/ calculated from quasi-neutrality and Ampere's law, respectively
TEDIT, a computer code for studying the time evolution of drift instabilities in a torus
Energy Technology Data Exchange (ETDEWEB)
van Rij, W.I.; Beasley, C.O. Jr.
1983-07-01
TEDIT is an initial-value program that calculates the time evolution of drift instabilities in a toroidal plasma with shear and in a slab-geometry approximation. The electron and ion kinetic equations are advanced in time, with the electrostatic potential phi and vector potential A/sub parallel/ calculated from quasi-neutrality and Ampere's law, respectively.
ADVANCED CUTTINGS TRANSPORT STUDY
Energy Technology Data Exchange (ETDEWEB)
Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Evren Ozbayoglu; Lei Zhou
2002-04-30
This is the third quarterly progress report for Year 3 of the ACTS Project. It includes a review of progress made in: (1) Flow Loop construction and development and (2) research tasks during the period of time between Jan. 1, 2002 and Mar. 31, 2002. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Separation System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 9b): ''Study of Foam Flow Behavior Under EPET Conditions'', (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (e) Research on three instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), Foam texture while transporting cuttings. (Task 12), and Viscosity of Foam under EPET (Task 9b); (f) Development of a Safety program for the ACTS Flow Loop, progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S); and (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.
ADVANCED CUTTINGS TRANSPORT STUDY
Energy Technology Data Exchange (ETDEWEB)
Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Affonso Lourenco; Evren Ozbayoglu; Lei Zhou
2002-01-30
This is the second quarterly progress report for Year 3 of the ACTS project. It includes a review of progress made in: (1) Flow Loop development and (2) research tasks during the period of time between Oct 1, 2001 and Dec. 31, 2001. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 3: Addition of a Cuttings Injection/Collection System), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (d) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (e) Research on instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), and Foam properties while transporting cuttings. (Task 12), (f) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (g) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.
ADVANCED CUTTINGS TRANSPORT STUDY
Energy Technology Data Exchange (ETDEWEB)
Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira; Lei Zhou
2000-01-30
This is the second quarterly progress report for Year 2 of the ACTS project. It includes a review of progress made in Flow Loop development and research during the period of time between Oct 1, 2000 and December 31, 2000. This report presents a review of progress on the following specific tasks: (a) Design and development of an Advanced Cuttings Transport Facility (Task 2: Addition of a foam generation and breaker system), (b) Research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (c) Research project (Task 7): ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (d) Research project (Task 8): ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (e) Research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Research project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (g) Research on instrumentation tasks to measure: Cuttings concentration and distribution in a flowing slurry (Task 11), and Foam properties while transporting cuttings. (Task 12), (h) Development of a Safety program for the ACTS Flow Loop. Progress on a comprehensive safety review of all flow-loop components and operational procedures. (Task 1S). (i) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members. The tasks Completed During This Quarter are Task 7 and Task 8.
ADVANCED CUTTINGS TRANSPORT STUDY
Energy Technology Data Exchange (ETDEWEB)
Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Gerald Kane; Mark Pickell; Len Volk; Mike Volk; Barkim Demirdal; Affonso Lourenco; Evren Ozbayoglu; Paco Vieira
2000-10-30
This is the first quarterly progress report for Year 2 of the ACTS project. It includes a review of progress made in Flow Loop development and research during the period of time between July 14, 2000 and September 30, 2000. This report presents information on the following specific tasks: (a) Progress in Advanced Cuttings Transport Facility design and development (Task 2), (b) Progress on research project (Task 8): ''Study of Flow of Synthetic Drilling Fluids Under Elevated Pressure and Temperature Conditions'', (c) Progress on research project (Task 6): ''Study of Cuttings Transport with Foam Under LPAT Conditions (Joint Project with TUDRP)'', (d) Progress on research project (Task 7): ''Study of Cuttings Transport with Aerated Muds Under LPAT Conditions (Joint Project with TUDRP)'', (e) Progress on research project (Task 9): ''Study of Foam Flow Behavior Under EPET Conditions'', (f) Initiate research on project (Task 10): ''Study of Cuttings Transport with Aerated Mud Under Elevated Pressure and Temperature Conditions'', (g) Progress on instrumentation tasks to measure: Cuttings concentration and distribution (Tasks 11), and Foam properties (Task 12), (h) Initiate a comprehensive safety review of all flow-loop components and operational procedures. Since the previous Task 1 has been completed, we will now designate this new task as: (Task 1S). (i) Activities towards technology transfer and developing contacts with Petroleum and service company members, and increasing the number of JIP members.
The nature of the torus in the heavily obscured AGN Markarian 3: an X-ray study
DEFF Research Database (Denmark)
Guainazzi, M.; Risaliti, G.; Awaki, H.;
2016-01-01
matter has an opening angle ≃66°, and is seen at a grazing angle through its upper rim (inclination angle ≃70°). We report a possible occultation event during the 2014 campaign. If the torus is constituted by a system of clouds sharing the same column density, this event allows us to constrain their...
Torus-doubling process via strange nonchaotic attractors
International Nuclear Information System (INIS)
Torus-doubling bifurcations typically occur only a finite number of times. It has been assumed that torus-doubling bifurcations in quasiperiodically forced systems are interrupted by the appearance of strange nonchaotic attractors (SNAs). In the present Letter, we study a quasiperiodically forced noninvertible map and report the occurrence of a torus-doubling process via SNAs. The mechanism of this process is numerically clarified. Furthermore, this process is experimentally demonstrated in a switched-capacitor integrated circuit. -- Highlights: ► We report the occurrence of a torus-doubling process via strange nonchaotic attractors (SNAs). ► The process consists of the gradual fractalization of a torus and the Heagy–Hammel transition. ► The torus-doubling process via SNAs is also experimentally demonstrated in an electronic circuit.
International Nuclear Information System (INIS)
Considering the recent increase in energy consumption. aide associated environmental risks, new trails are followed today to develop the use of clean and renewable alternative energies. In this context hydrogen seems to be a serious solution and this study, based on micro-algae photosynthetic capacities exploitation, will allow to devise a process for hydrogen production from only water and solar energy without greenhouse gas release. The sulphur deprivation protocol on TAP medium, known to lead to hydrogen production in Chlamydomonas reinhardtii species was particularly studied. At the metabolic level, two important phenomena are induced under these conditions: an over-accumulation of the intracellular starch reserves and a simultaneous alteration of the PsII activity which leads to anoxia and Fe-hydrogenase induction, an enzyme with a strong specific activity responsible for the hydrogen production. The contribution of the two electron transfer pathways implied in the hydrogen production process (PsII-dependent and PSII-independent) as well as the importance of the previously accumulated starch were highlighted here. We also investigated the potential for designing autotrophic protocols for hydrogen photoproduction. Various protocols, considered to be relevant, were then transposed on a torus photo-bioreactor, specifically developed in this study and which allows the control of culture parameters as well as the precise measurement of gas release kinetics, in order to obtain first estimates of productivity of the system. Integration of the physical; aspects of the pilot and biological aspects of the process in a model, finally opens new prospects for subject development, in particular for a reasoned optimization of hydrogen production via this double physiology/process approach. (author)
Maintenance of torus components for the fusion experimental reactor (FER)
International Nuclear Information System (INIS)
Maintenance of torus components is one of key technologies for the Fusion Experimental Reactor (FER), which is the device planned to succeed the JT-60 tokamak device. The objective of the present study is to develop a reliable, feasible and simple maintenance systems for torus components such as divertor and movable shield modules. This paper describes the reactor structure and its maintenance scheme of FER and the maintenance systems for torus components. A 1/4-scale mock-up of FER is also introduced, which was made to demonstrate the feasibility of the maintenance system for torus components of FER
2003-01-01
A cut-away schematic of Jupiter's space environment shows magnetically trapped radiation ions (in red), the neutral gas torus of the volcanic moon Io (green) and the newly discovered neutral gas torus of the moon Europa (blue). The white lines represent magnetic field lines.Energetic neutral atoms (ENA) are emitted from the Europa torus regions because of the interaction between the trapped ions and the neutral gases. The Magnetospheric Imaging Instrument on NASA's Cassini spacecraft imaged those energetic neutral atoms in early 2001 during Cassini's flyby of Jupiter. Energetic neutral atoms also come from Jupiter when radiation ions impinge onto Jupiter's upper atmosphere.Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages Cassini for NASA's Office of Space Science, Washington, D.C.
Juhasz, Antal; Horanyi, Mihaly
1995-01-01
We investigate the orbital dynamics of small dust particles generated via the continuous micrometeoroid bombardment of the Martian moons. In addition to Mar's oblateness, we also consider the radiation pressure perturbation that is complicated by the planet's eccentric orbit and tilted rotational axis. Considering the production rates and the lifetimes of dust grains, we show that particles from Deimos with radii of about 15 micrometers are expected to dominate the population of a permanently present and tilted dust torus. This torus has an estimated peak number density of approximately equals 5 x 10(exp -12)/cu cm and an optical depth of approximately equals 4 x 10(exp -8).
ADVANCED CUTTINGS TRANSPORT STUDY
Energy Technology Data Exchange (ETDEWEB)
Stefan Miska; Troy Reed; Ergun Kuru
2004-09-30
The Advanced Cuttings Transport Study (ACTS) was a 5-year JIP project undertaken at the University of Tulsa (TU). The project was sponsored by the U.S. Department of Energy (DOE) and JIP member companies. The objectives of the project were: (1) to develop and construct a new research facility that would allow three-phase (gas, liquid and cuttings) flow experiments under ambient and EPET (elevated pressure and temperature) conditions, and at different angle of inclinations and drill pipe rotation speeds; (2) to conduct experiments and develop a data base for the industry and academia; and (3) to develop mechanistic models for optimization of drilling hydraulics and cuttings transport. This project consisted of research studies, flow loop construction and instrumentation development. Following a one-year period for basic flow loop construction, a proposal was submitted by TU to the DOE for a five-year project that was organized in such a manner as to provide a logical progression of research experiments as well as additions to the basic flow loop. The flow loop additions and improvements included: (1) elevated temperature capability; (2) two-phase (gas and liquid, foam etc.) capability; (3) cuttings injection and removal system; (4) drill pipe rotation system; and (5) drilling section elevation system. In parallel with the flow loop construction, hydraulics and cuttings transport studies were preformed using drilling foams and aerated muds. In addition, hydraulics and rheology of synthetic drilling fluids were investigated. The studies were performed under ambient and EPET conditions. The effects of temperature and pressure on the hydraulics and cuttings transport were investigated. Mechanistic models were developed to predict frictional pressure loss and cuttings transport in horizontal and near-horizontal configurations. Model predictions were compared with the measured data. Predominantly, model predictions show satisfactory agreements with the measured data. As a
International Nuclear Information System (INIS)
The issue of First wall materials and compatibility with ITER /DEMO relevant plasmas is among the RD missions for possible new European plasma fusion devices that the FAST project will address. FAST can operate with ITER relevant values of P/R (up to 22 MW/m, against the ITER 24 MW/m, inclusive of the α particles power), thanks to its compactness; thus it can investigate the physics of large heat loads on divertor plates. The FAST divertor will be made of bulk W tiles, for basic operations, but also fully toroidal divertor targets made of liquid lithium (L-Li) are foreseen. To have reliable predictions of the thermal loads on the divertor plates and of the core plasma purity a number of numerical self-consistent simulations have been made for the H-mode and steady-state scenario by using the code COREDIV. This code, already validated in the past on experimental data (namely JET, FTU, Textor), is able to describe self-consistently the core and edge plasma in a tokamak device by imposing the continuity of energy and particle fluxes and of particle densities and temperatures at the separatrix. In the present work the results of such calculations will be illustrated, including heat loads on the divertor. The overall picture shows that, marginally in the intermediate and, necessarily in the high density H-mode scenarios (e>=2 and 5·1020 m-3 respectively), impurity seeding should be foreseen with W as target material: however, only a small amount of Ar (0.03% atomic concentration), not affecting the core purity, is sufficient to maintain the divertor peak loads below 18 MW/m2, that represents the safety limit for the W mono block technology, presently accepted for the ITER divertor tiles. Li always needs additional impurities for decreasing divertor heat loads, the Zeff value being ≤ than 1.8. At low plasma densities (but ≥ 1.3·1020 m-3), typical of steady state regimes, W by alone is effective in dissipating the input power by radiative losses, without excessive core contamination. Impurity seeding would lead to excessive W sputtering by Ar and too high Zeff . The impact of the ELMs on the divertor in the case of a good H-mode with low pedestal dimensionless collisionality will be discussed too
International Nuclear Information System (INIS)
Among the R and D missions for possible new European plasma fusion devices, the FAST project will address the issue of 'First wall materials and compatibility with ITER /DEMO relevant plasmas'. FAST can operate with ITER relevant values of P/R (up to 22 MW/m, against the ITER 24 MW/m, inclusive of the alpha particles power), thanks to its compactness; thus it can investigate the physics of large heat loads on divertor plates. The FAST divertor will be made of bulk W tiles, for basic operations, but also fully toroidal divertor targets made of liquid lithium (L-Li) are foreseen. Viability tests of such a solution for DEMO divertor will be carried out as final step of an extended program started on FTU tokamak by using a liquid lithium limITER. To have reliable predictions of the thermal loads on the divertor plates and of the core plasma purity a number of numerical self-consistent simulations have been made for the H-mode and steady-state scenario by using the code COREDIV. This code, already validated in the past on experimental data (namely JET, FTU, Textor), is able to describe self-consistently the core and edge plasma in a tokamak device by imposing the continuity of energy and particle fluxes and of particle densities and temperatures at the separatrix. In the present work the results of such calculations will be illustrated, including heat loads on the divertor. The overall picture shows that at the low plasma densities typical of steady state regimes W is effective in dissipating input power by radiative losses, while Li needs additional impurities (Ar, Ne). In the intermediate and, mainly, in the high density H-mode scenarios impurity seeding is needed with either Li or W as target material, but a small (0.08% atomic concentration) amount of Ar, not affecting the core purity, is sufficient to maintain the divertor peak loads below 18 MW/m2 that represents the safety limit for the W monoblock technology, presently accepted for the ITER divertor tiles. The impact of the ELMs on the divertor in the case of a good H-mode with low pedestal dimensionless collisionality will be discussed too. (author)
Unknotting surface links which are coverings of a trivial torus knot
NAKAMURA, Inasa
2009-01-01
We consider surface links in the 4-space which are presented by the form of simple branched coverings over the standard torus, which we call torus-covering links. In this paper, we study unknotting numbers of torus-covering links. In some cases, we can determine the unknotting numbers.
ELMO Bumpy Torus Reactor (EBTR) reference design
International Nuclear Information System (INIS)
The goal of the ELMO Bumpy Torus Reactor (EBTR) study is the evaluation of the EBT confinement concept as the basis for development of a commercial fusion power reactor. A multidisciplinary, self-consistent treatment of EBT reactor scaling and design has been completed and a reference design (EBTR-48) has been developed. This design, based on a realistic plasma model and relatively conservative engineering parameters (i.e., 1 MW/m2 neutron wall loading and a 7.3 T maximum toroidal field), is a steady state, ignited-mode system with high plasma power density and aspect ratio. The total thermal power of EBTR-48, exclusive of blanket multiplication, is 4000 MW; the design is based on a standard module and the design power level for a particular plant is determined by the number of modules used. Several design variants have been investigated in detail to illustrate the effect of near-term and advanced technologies and to illustrate the design freedom offered by devices with low field and high aspect ratio. The high aspect ratio simplifies many aspects of the design, most notably those associated with remote maintenance, accessibility, and repair. It appears that a commercially successful EBTR could be constructed with only slight advances in existing technology, if the present understanding of the physics can be extrapolated to the reactor regime and does not differ markedly from the model developed for this study
Orndoff, Evelyne; Poritz, Darwin
2014-01-01
All human space missions require significant logistical mass and volume that add an unprecedented burden on longduration missions beyond low-Earth orbit. For these missions with limited cleaning resources, a new wardrobe must be developed to reduce this logistical burden by reducing clothing mass and extending clothing wear. The present studies have been undertaken, for the first time, to measure length of wear and to assess the acceptance of such extended wear. Garments in these studies are commercially available exercise T-shirts and shorts, routine-wear T-shirts, and longsleeved pullover shirts. Fabric composition (cotton, polyester, light-weight, superfine Merino wool, modacrylic, cotton/rayon, polyester/Cocona, modacrylic/Xstatic, modacrylic/rayon, modacrylic/lyocell/aramid), construction (open knit, tight knit, open weave, tight weave), and finishing treatment (none, quaternary ammonium salt) are the independent variables. Eleven studies are reported here: five studies of exercise T-shirts, three of exercise shorts, two of routine wear Tshirts, and one of shirts used as sleep-wear. All studies are conducted in a climate-controlled environment, similar to a space vehicle's. For exercise clothing, study participants wear the garments during aerobic exercise. For routine wear clothing, study participants wear the T-shirts daily in an office or laboratory. Daily questionnaires collected data on ordinal preferences of nine sensory elements and on reason for retiring a used garment. Study 1 compares knitted cotton, polyester, and Merino exercise T-shirts (61 participants), study 2, knitted polyester, modacrylic, and polyester/Cocona exercise T-shirts (40 participants), study 3, cotton and polyester exercise shorts, knitted and woven (70 participants), all three using factorial experimental designs with and without a finishing treatment, conducted at the Johnson Space Center, sharing study participants. Study 4 compares knitted polyester and ZQ Merino exercise T
Richardson, John D.; Eviatar, A.; Delitsky, M. L.
1990-01-01
Prior to the Voyager encounter with Neptune, Delitsky et al. (1989) predicted that a torus of ions emanating from Triton would be discovered. These predictions are reexamined in light of the Voyager results. Sputtering of Triton's atmosphere can produce the heavy ion densities inferred at Triton's orbit by the Voyager plasma experiment if the ion residence time is about 30 days. The torus is found to be longitudinally asymmetric near Triton, with peak densities at longitudes of 170 and 350 deg. The total nitrogen flux due to sputtering is about 2 x 10 to the 21st/s. The consequences of larger escape fluxes of both N2 and H2 are investigated; it is difficult to reconcile large escape fluxes with the plasma and ultraviolet spectrometer observations.
Spherical torus fusion reactor
Peng, Yueng-Kay M.
1989-01-01
A fusion reactor is provided having a near spherical-shaped plasma with a modest central opening through which straight segments of toroidal field coils extend that carry electrical current for generating a toroidal magnet plasma confinement fields. By retaining only the indispensable components inboard of the plasma torus, principally the cooled toroidal field conductors and in some cases a vacuum containment vessel wall, the fusion reactor features an exceptionally small aspect ratio (typically about 1.5), a naturally elongated plasma cross section without extensive field shaping, requires low strength magnetic containment fields, small size and high beta. These features combine to produce a spherical torus plasma in a unique physics regime which permits compact fusion at low field and modest cost.
Saturn in hot water: viscous evolution of the Enceladus torus
Farmer, Alison J
2008-01-01
The detection of outgassing water vapor from Enceladus is one of the great breakthroughs of the Cassini mission. The fate of this water once ionized has been widely studied; here we investigate the effects of purely neutral-neutral interactions within the Enceladus torus. We find that, thanks in part to the polar nature of the water molecule, a cold (~180 K) neutral torus would undergo rapid viscous heating and spread to the extent of the observed hydroxyl cloud, before plasma effects become important. We investigate the physics behind the spreading of the torus, paying particular attention to the competition between heating and rotational line cooling. A steady-state torus model is constructed, and it is demonstrated that the torus will be observable in the millimeter band with the upcoming Herschel satellite. The relative strength of rotational lines could be used to distinguish between physical models for the neutral cloud.
High-spin torus isomers and their precession motions
Ichikawa, T.; Matsuyanagi, K.; Maruhn, J. A.; Itagaki, N.
2014-09-01
Background: In our previous study, we found that an exotic isomer with a torus shape may exist in the high-spin, highly excited states of Ca40. The z component of the total angular momentum, Jz=60ℏ, of this torus isomer is constructed by totally aligning 12 single-particle angular momenta in the direction of the symmetry axis of the density distribution. The torus isomer executes precession motion with the rigid-body moments of inertia about an axis perpendicular to the symmetry axis. The investigation, however, has been focused only on Ca40. Purpose: We systematically investigate the existence of exotic torus isomers and their precession motions for a series of N =Z even-even nuclei from Si28 to Ni56. We analyze the microscopic shell structure of the torus isomer and discuss why the torus shape is generated beyond the limit of large oblate deformation. Method: We use the cranked three-dimensional Hartree-Fock method with various Skyrme interactions in a systematic search for high-spin torus isomers. We use the three-dimensional time-dependent Hartree-Fock method for describing the precession motion of the torus isomer. Results: We obtain high-spin torus isomers in Ar36,Ca40,Ti44,Cr48, and Fe52. The emergence of the torus isomers is associated with the alignments of single-particle angular momenta, which is the same mechanism as found in Ca40. It is found that all the obtained torus isomers execute the precession motion at least two rotational periods. The moment of inertia about a perpendicular axis, which characterizes the precession motion, is found to be close to the classical rigid-body value. Conclusions: The high-spin torus isomer of Ca40 is not an exceptional case. Similar torus isomers exist widely in nuclei from Ar36 to Fe52 and they execute the precession motion. The torus shape is generated beyond the limit of large oblate deformation by eliminating the 0s components from all the deformed single-particle wave functions to maximize their mutual
Design study of HiSOR-II lightsource ring with torus-knot type compact accumulator ring
International Nuclear Information System (INIS)
We proposed a ring in which a beam orbit is not closed with one turn and return to starting point after multiple turns around the ring. The idea of this new accumulation ring was inspired based on the torus knot theory. This ring has a very long closed orbit in comparison with a conventional ring which has the orbit of one turn. Therefore this ring has long beam orbit before returning to the starting point and has many straight sections which is advantageous to installation of insertion devices. We are designing the light source ring based on the shape of a (11, 3) torus knot type accumulator ring for HiSOR-II storage ring. The diameter of this ring is as compact as 15 m, but its total orbit length is as long as 130 m. On the other hand, this ring must achieve low emittance to operate as the 3rd generation light source ring. Therefore we designed lattice of this ring and achieved enough low emittance as 3rd generation light source ring by using bending magnets with combined function. (author)
Triton torus and Neptune aurora
Cheng, Andrew F.
1990-01-01
Triton is shown to be the dominant source of plasma for L equal to or greater than 7 in the magnetosphere of Neptune. Triton maintains a neutral hydrogen torus of average density comparable to a greater than that of the Titan torus at Saturn. The Triton torus may be detectable in H Lyman-alpha emissions. However, the energy source from plasma outward transport and mass loading in the Triton torus is insufficient to explain the Neptune aurora. It is proposed that Neptune's aurora is driven mainly by a solar wind interaction.
On Chow quotients of torus actions
Bäker, Hendrik; Keicher, Simon
2012-01-01
We consider torus actions on Mori dream spaces and ask whether the associated Chow quotient is again a Mori dream space and, if so, what does its Cox ring look like. We provide general tools for the study of these problems and give solutions for k*-actions on smooth quadrics.
ADVANCED CUTTINGS TRANSPORT STUDY
Energy Technology Data Exchange (ETDEWEB)
Troy Reed; Stefan Miska; Nicholas Takach; Kaveh Ashenayi; Mark Pickell; Len Volk; Mike Volk; Lei Zhou; Zhu Chen; Crystal Redden; Aimee Washington
2003-04-30
Experiments on the flow loop are continuing. Improvements to the software for data acquisition are being made as additional experience with three-phase flow is gained. Modifications are being made to the Cuttings Injection System in order to improve control and the precision of cuttings injection. The design details for a drill-pipe Rotation System have been completed. A US Patent was filed on October 28, 2002 for a new design for an instrument that can generate a variety of foams under elevated pressures and temperatures and then transfer the test foam to a viscometer for measurements of viscosity. Theoretical analyses of cuttings transport phenomena based on a layered model is under development. Calibrations of two nuclear densitometers have been completed. Baseline tests have been run to determine wall roughness in the 4 different tests sections (i.e. 2-in, 3-in, 4-in pipes and 5.76-in by 3.5-in annulus) of the flow loop. Tests have also been conducted with aerated fluids at EPET conditions. Preliminary experiments on the two candidate aqueous foam formulations were conducted which included rheological tests of the base fluid and foam stability reports. These were conducted after acceptance of the proposal on the Study of Cuttings Transport with Foam Under Elevated Pressure and Elevated Temperature Conditions. Preparation of a test matrix for cuttings-transport experiments with foam in the ACTF is also under way. A controller for instrumentation to measure cuttings concentration and distribution has been designed that can control four transceivers at a time. A prototype of the control circuit board was built and tested. Tests showed that there was a problem with radiated noise. AN improved circuit board was designed and sent to an external expert to verify the new design. The new board is being fabricated and will first be tested with static water and gravel in an annulus at elevated temperatures. A series of viscometer tests to measure foam properties have
Particle on a torus knot: a Hamiltonian analysis
Das, Praloy
2015-01-01
We have studied the dynamics and symmetries of a particle constrained to move in a torus knot. The Hamiltonian system turns out to be Second Class in Dirac's formulation and the Dirac brackets yield novel noncommutative structures. The equations of motion are obtained for a path in general where the knot is present in the particle orbit but it is not restricted to a particular torus. We also study the motion when it is restricted to a specific torus. The rotational symmetries are studied as well.
Ion Temperature Control of the Io Plasma Torus
Delamere, P. A.; Schneider, N. M.; Steffl, A. J.; Robbins, S. J.
2005-01-01
We report on observational and theoretical studies of ion temperature in the Io plasma torus. Ion temperature is a critical factor for two reasons. First, ions are a major supplier of energy to the torus electrons which power the intense EUV emissions. Second, ion temperature determines the vertical extent of plasma along field lines. Higher temperatures spread plasma out, lowers the density and slows reaction rates. The combined effects can play a controlling role in torus energetics and chemistry. An unexpected tool for the study of ion temperature is the longitudinal structure in the plasma torus which often manifests itself as periodic brightness variations. Opposite sides of the torus (especially magnetic longitudes 20 and 200 degrees) have been observed on numerous occasions to have dramatically different brightness, density, composition, ionization state, electron temperature and ion temperature. These asymmetries must ultimately be driven by different energy flows on the opposite sides, presenting an opportunity to observe key torus processes operating under different conditions. The most comprehensive dataset for the study of longitudinal variations was obtained by the Cassini UVIS instrument during its Jupiter flyby. Steffl (Ph.D. thesis, 2005) identified longitudinal variations in all the quantities listed above wit the exception of ion temperature. We extend his work by undertaking the first search for such variation in the UVIS dataset. We also report on a 'square centimeter' model of the torus which extend the traditional 'cubic centimeter' models by including the controlling effects of ion temperature more completely.
Kraft, Ralph; Kimura, Tomoki; Elsner, Ronald; Branduardi-Raymont, Graziella; Gladstone, Randy; Badman, Sarah Victoria; Ezoe, Yuichiro; Murakami, Go; Murray, Stephen S.; Roediger, Elke; Tsuchiya, Fuminori; Yamazaki, Atsushi; Yoshikawa, Ichiro; Yoshioka, Kazuo
2014-01-01
We present preliminary results from a coordinated Hisaki/Chandra/XMM-Newton observational campaign of the Jovian aurora and Io plasma torus. The data were taken over a three week period in April, 2014. Jupiter was observed continuously with Hisaki, six times with the Chandra/HRC instrument for roughly 12 hours per observation, and twice by XMM-Newton. The goal of this observational campaign was to understand how energy and matter are exchanged between the Jovian aurora, the IPT, and the Solar wind. X-ray observations provide key diagnostics on highly stripped ions and keV electrons in the Jovian magnetosphere. We use the temporal, spatial, and spectral capabilities of the three instruments to search for correlated variability between the Solar wind, the EUV-emitting plasma of the IPT and UV aurora, and the ions responsible for the X-ray aurora. Preliminary analysis suggests a strong 45 min periodicity in the EUV emission from the electron aurora. There is some evidence for complex variability of the X-ray auroras on scales of tens of minutes. There is also clear morphological changes in the X-ray aurora that do not appear to be correlated with either variations in the IPT or Solar wind.
The nature of the torus in the heavily obscured AGN Markarian 3: an X-ray study
Guainazzi, M; Awaki, H; Arevalo, P; Bauer, F E; Bianchi, S; Boggs, S E; Brandt, W N; Brightman, M; Christensen, F E; Craig, W W; Forster, K; Hailey, C J; Harrison, F; Koss, M; Longinotti, A; Markwardt, C; Marinucci, A; Matt, G; Reynolds, C S; Ricci, C; Stern, D; Svoboda, J; Walton, D; Zhang, W
2016-01-01
In this paper we report the results of an X-ray monitoring campaign on the heavily obscured Seyfert galaxy Markarian 3 carried out between the fall of 2014 and the spring of 2015 with NuSTAR, Suzaku and XMM-Newton. The hard X-ray spectrum of Markarian 3 is variable on all the time scales probed by our campaign, down to a few days. The observed continuum variability is due to an intrinsically variable primary continuum seen in transmission through a large, but still Compton-thin column density (N_H~0.8-1.1$\\times$10$^{24}$ cm$^{-2}$). If arranged in a spherical-toroidal geometry, the Compton scattering matter has an opening angle ~66 degrees and is seen at a grazing angle through its upper rim (inclination angle ~70 degrees). We report a possible occultation event during the 2014 campaign. If the torus is constituted by a system of clouds sharing the same column density, this event allows us to constrain their number (17$\\pm$5) and individual column density, [~(4.9$\\pm$1.5)$\\times$10$^{22}$ cm$^{-2}$]. The com...
Resonant torus-assisted tunneling.
Yi, Chang-Hwan; Yu, Hyeon-Hye; Kim, Chil-Min
2016-01-01
We report a new type of dynamical tunneling, which is mediated by a resonant torus, i.e., a nonisolated periodic orbit. To elucidate the phenomenon, we take an open elliptic cavity and show that a pair of resonances localized on two classically disconnected tori tunnel through a resonant torus when they interact with each other. This so-called resonant torus-assisted tunneling is verified by using Husimi functions, corresponding actions, Husimi function distributions, and the standard deviations of the actions. PMID:26871067
Advanced nuclear systems. Review study
International Nuclear Information System (INIS)
The task of this review study is to from provide an overview of the developments in the field of the various advanced nuclear systems, and to create the basis for more comprehensive studies of technology assessment. In an overview the concepts for advanced nuclear systems pursued worldwide are subdivided into eight subgroups. A coarse examination raster (set pattern) is developed to enable a detailed examination of the selected systems. In addition to a focus on enhanced safety features, further aspects are also taken into consideration, like the lowering of the proliferation risk, the enhancement of the economic competitiveness of the facilities and new usage possibilities (for instance concerning the relaxation of the waste disposal problem or the usage of alternative fuels to uranium). The question about the expected time span for realization and the discussion about the obstacles on the way to a commercially usable reactor also play a substantial role as well as disposal requirements as far as they can be presently recognized. In the central chapter of this study, the documentation of the representatively selected concepts is evaluated as well as existing technology assessment studies and expert opinions. In a few cases where this appears to be necessary, according technical literature, further policy advisory reports, expert statements as well as other relevant sources are taken into account. Contradictions, different assessments and dissents in the literature as well as a few unsettled questions are thus indicated. The potential of advanced nuclear systems with respect to economical and societal as well as environmental objectives cannot exclusively be measured by the corresponding intrinsic or in comparison remarkable technical improvements. The acceptability of novel or improved systems in nuclear technology will have to be judged by their convincing solutions for the crucial questions of safety, nuclear waste and risk of proliferation of nuclear weapons
Closed String Thermal Torus From Thermofield Dynamics
Abdalla, Maria Christina B; Nedel, D L; Nedel, Daniel L.
2005-01-01
In this work the relationship between Imaginary time and Thermo Field Dynamics (TFD) Formalism is made, when both formalism are used to study closed strings at finite temperature. The TFD approach starts by duplicating the degrees of freedom of the system, defining an auxiliary string (tilde string). Bogoliubov transformation is implemented in order to lead the system to finite temperature. We demonstrated that the effect of that Bogoliubov transformation is to glue together both the string and the tilde string in order to make a torus; the very same that comes when the Imaginary Time formalism is applied to closed string. The thermal vacuum appears as the boundary state for this identification. Also, from the thermal state condition, a Kubo-Martin-Schwinger condition for the torus topology is presented.
Exploring Torus Universes in Causal Dynamical Triangulations
Budd, T G
2013-01-01
Motivated by the search for new observables in nonperturbative quantum gravity, we consider Causal Dynamical Triangulations (CDT) in 2+1 dimensions with the spatial topology of a torus. This system is of particular interest, because one can study not only the global scale factor, but also global shape variables in the presence of arbitrary quantum fluctuations of the geometry. Our initial investigation focusses on the dynamics of the scale factor and uncovers a qualitatively new behaviour, which leads us to investigate a novel type of boundary conditions for the path integral. Comparing large-scale features of the emergent quantum geometry in numerical simulations with a classical minisuperspace formulation, we find partial agreement. By measuring the correlation matrix of volume fluctuations we succeed in reconstructing the effective action for the scale factor directly from the simulation data. Apart from setting the stage for the analysis of shape dynamics on the torus, the new set-up highlights the role o...
Numerical simulation of plasma transport driven by the Io torus
Yang, Y. S.; Wolf, R. A.; Spiro, R. W.; Dessler, A. J.
1992-01-01
The Rice convection model (RCM) has been modified to a form suitable for Jupiter (RCM-J) to study plasma interchange motion in and near the Io plasma torus. The net result of the interchange is that flux tubes, heavily loaded with torus plasma, are transported outward, to be replaced by tubes containing little low-energy (less than 1 keV) plasma. The process is numerically simulated in terms of time evolution from an initial torus that is longitudinally asymmetric and with gradually decreasing density outward from Io's orbit. In the simulations, the nonlinear stage of the instability characteristically exhibits outreaching fingers of heavily-loaded flux tubes that lengthen at an accelerating rate. The principal finding is that the primary geometrical form of outward transport of torus plasma in Jupiter's magnetosphere is through long, outward-moving fingers of plasma. In the simulations, the fingers mainly form in the active sector of the Io torus (the heavier side of the asymmetric torus), and they are spaced longitudinally roughly 20 deg apart.
Advanced Collaborative Emissions Study (ACES)
Energy Technology Data Exchange (ETDEWEB)
Greenbaum, Daniel; Costantini, Maria; Van Erp, Annemoon; Shaikh, Rashid; Bailey, Brent; Tennant, Chris; Khalek, Imad; Mauderly, Joe; McDonald, Jacob; Zielinska, Barbara; Bemis, Jeffrey; Storey, John; Hallberg, Lance; Clark, Nigel
2013-12-31
The objective of the Advanced Collaborative Emissions Study (ACES) was to determine before widespread commercial deployment whether or not the new, energy-efficient, heavy duty diesel engines (2007 and 2010 EPA Emissions Standards Compliant) may generate anticipated toxic emissions that could adversely affect the environment and human health. ACES was planned to take place in three phases. In Phase 1, extensive emissions characterization of four production-intent prototype engine and control systems designed to meet 2007 standards for nitrogen oxides (NOx) and particulate matter (PM) was conducted at an existing emissions characterization facility: Southwest Research Institute (SwRI). One of the tested engines was selected (at random, after careful comparison of results) for health testing in Phase 3. In Phase 2, extensive emission characterization of three production-intent prototype engine and control systems meeting the 2010 standards (including more advanced NOx controls to meet the more stringent 2010 NOx standards) was conducted at the same test facility. In Phase 3, one engine/aftertreatment system selected from Phase 1 was further characterized during health effects studies (at an existing inhalation toxicology laboratory: Lovelace Respiratory Research Institute, [LRRI]) to form the basis of the ACES safety assessment. The Department of Energy (DOE) award provided funding for emissions characterization in Phases 1 and 2 as well as exposure characterization in Phase 3. The main health analyses in Phase 3 were funded separately and are not reported here.
Gallagher, S C; Everett, J E; Keating, S; Deo, R P
2013-01-01
Mass ejection in the form of winds or jets appears to be as fundamental to quasar activity as accretion, and can be directly observed in many objects with broadened and blue-shifted UV absorption features. A convincing argument for radiation pressure driving this ionized outflow can be made within the dust sublimation radius. Beyond, radiation pressure is even more important, as high energy photons from the central engine can now push on dust grains. This physics underlies the dusty-wind model for the putative obscuring torus. Specifically, the dusty wind in our model is first launched from the outer accretion disk as a magneto-centrifugal wind and then accelerated and shaped by radiation pressure from the central continuum. Such a wind can plausibly account for both the necessary obscuring medium to explain the ratio of broad-to-narrow-line objects and the mid-infrared emission commonly seen in quasar spectral energy distributions. A convincing demonstration that large-scale, organized magnetic fields are pr...
Torus Knots and the Topological Vertex
Jockers, Hans; Soroush, Masoud
2012-01-01
We propose a class of toric Lagrangian A-branes on the resolved conifold that is suitable to describe torus knots on S^3. The key role is played by the SL(2,Z) transformation, which generates a general torus knot from the unknot. Applying the topological vertex to the proposed A-branes, we rederive the colored HOMFLY polynomials for torus knots, in agreement with the Rosso and Jones formula. We show that our A-model construction is mirror symmetric to the B-model analysis of Brini, Eynard and Marino. Comparing to the recent proposal by Aganagic and Vafa for knots on S^3, we demonstrate that the disk amplitude of the A-brane associated to any knot is sufficient to reconstruct the entire B-model spectral curve. Finally, the construction of toric Lagrangian A-branes is generalized to other local toric Calabi-Yau geometries, which paves the road to study knots in other three-manifolds such as lens spaces.
Charge of the torus, evidence of the superfield and square-root operator
International Nuclear Information System (INIS)
We study potential and corresponding Green functions generated by charged ring, disk, holed coin and torus. It turns out that the innermost structure of these extended charges is associated with nonlocal photon propagator. It is shown that propagator arisen from charged torus potential consists of two different parts: nonlocal photon propagator and propagator of neutrino-like particle which is described by the square-root operator equation. We examine the potential of the torus and its propagator as appearance of superfields in terms of the photon and massless fermion (photino). Correspondence between the torus and square-root operator field is discussed too. (author)
Compact Manifolds Covered by a Torus
Demailly, Jean-Pierre; Hwang, Jun-Muk; Peternell, Thomas
2007-01-01
Let $X$ be a connected compact complex manifold admitting a finite surjective map $A \\to X$ from a complex torus $A.$ We prove that up to finite \\'etale cover, $X$ is a product of projective spaces and a torus.
Continuous families of Hamiltonian torus actions
Viña, Andrés
2008-01-01
We determine conditions under which two Hamiltonian torus actions on a symplectic manifold $M$ are homotopic by a family of Hamiltonian torus actions, when $M$ is a toric manifold and when $M$ is a coadjoint orbit.
p-Coloring Classes of Torus Knots
Breiland, Anna-Lisa; Oesper, Layla; Taalman, Laura
2009-01-01
We classify by elementary methods the $p$-colorability of torus knots, and prove that every $p$-colorable torus knot has exactly one nontrivial $p$-coloring class. As a consequence, we note that the two-fold branched cyclic cover of a torus knot complement has cyclic first homology group.
On the computation of torus link homology
Elias, Ben; Hogancamp, Matthew
2016-01-01
We introduce a new method for computing triply graded link homology, which is particularly well-adapted to torus links. Our main application is to the (n,n)-torus links, for which we give an exact answer for all n. In several cases, our computations verify conjectures of Gorsky et al relating homology of torus links with Hilbert schemes.
Skein Modules and the Noncommutative Torus
Frohman, Charles; Gelca, Razvan
1998-01-01
We show that the Kauffman bracket skein module of a cylinder over the torus embeds as a subalgebra of the noncommutative torus. Using this we derive nice formulas for the Jones-Wenzl idempotents and analyze the structure of the Kauffman bracket skein module of the unknot as a module over the Kauffman bracket skein module of a cylinder over the torus.
Morgan, J. S.
1985-01-01
Results of calculations are given for three-dimensional models of the Io torus, to analyze the spectroscopic data reported by Morgan (1985). The calculations included variations in the torus plasma properties with longitude, latitude, and distance from Jupiter. The spectroscopic data are compared with the Oliversen's (S II) images and with the in situ measurements made by Voyager 1. The hypothesis is tested that the optical east-west variations reported in Morgan (1985) are consistent with the convective motions suggested by Barbosa and Kivelson (1983) and Ip and Goertz (1983). It is shown that the optical intensity asymmetry can be explained as a natural consequence of the suggested convective motions.
NATO Advanced Study Institute on Advances in Chemical Reaction Dynamics
Capellos, Christos
1986-01-01
This book contains the formal lectures and contributed papers presented at the NATO Advanced Study Institute on. the Advances in Chemical Reaction Dynamics. The meeting convened at the city of Iraklion, Crete, Greece on 25 August 1985 and continued to 7 September 1985. The material presented describes the fundamental and recent advances in experimental and theoretical aspects of, reaction dynamics. A large section is devoted to electronically excited states, ionic species, and free radicals, relevant to chemical sys tems. In addition recent advances in gas phase polymerization, formation of clusters, and energy release processes in energetic materials were presented. Selected papers deal with topics such as the dynamics of electric field effects in low polar solutions, high electric field perturbations and relaxation of dipole equilibria, correlation in picosecond/laser pulse scattering, and applications to fast reaction dynamics. Picosecond transient Raman spectroscopy which has been used for the elucidati...
Recent Progress on Spherical Torus Research
Energy Technology Data Exchange (ETDEWEB)
Ono, Masayuki [PPPL; Kaita, Robert [PPPL
2014-01-01
The spherical torus or spherical tokamak (ST) is a member of the tokamak family with its aspect ratio (A = R0/a) reduced to A ~ 1.5, well below the normal tokamak operating range of A ≥ 2.5. As the aspect ratio is reduced, the ideal tokamak beta β (radio of plasma to magnetic pressure) stability limit increases rapidly, approximately as β ~ 1/A. The plasma current it can sustain for a given edge safety factor q-95 also increases rapidly. Because of the above, as well as the natural elongation κ, which makes its plasma shape appear spherical, the ST configuration can yield exceptionally high tokamak performance in a compact geometry. Due to its compactness and high performance, the ST configuration has various near term applications, including a compact fusion neutron source with low tritium consumption, in addition to its longer term goal of attractive fusion energy power source. Since the start of the two megaampere class ST facilities in 2000, National Spherical Torus Experiment (NSTX) in the US and Mega Ampere Spherical Tokamak (MAST) in UK, active ST research has been conducted worldwide. More than sixteen ST research facilities operating during this period have achieved remarkable advances in all of fusion science areas, involving fundamental fusion energy science as well as innovation. These results suggest exciting future prospects for ST research both near term and longer term. The present paper reviews the scientific progress made by the worldwide ST research community during this new mega-ampere-ST era.
Generalized Fuzzy Torus and its Modular Properties
Directory of Open Access Journals (Sweden)
Paul Schreivogl
2013-10-01
Full Text Available We consider a generalization of the basic fuzzy torus to a fuzzy torus with non-trivial modular parameter, based on a finite matrix algebra. We discuss the modular properties of this fuzzy torus, and compute the matrix Laplacian for a scalar field. In the semi-classical limit, the generalized fuzzy torus can be used to approximate a generic commutative torus represented by two generic vectors in the complex plane, with generic modular parameter τ. The effective classical geometry and the spectrum of the Laplacian are correctly reproduced in the limit. The spectrum of a matrix Dirac operator is also computed.
Generalized fuzzy torus and its modular properties
Schreivogl, Paul
2013-01-01
We consider a generalization of the basic fuzzy torus to a fuzzy torus with non-trivial modular parameter, based on a finite matrix algebra. We discuss the modular properties of this fuzzy torus, and compute the matrix Laplacian for a scalar field. In the semi-classical limit, the generalized fuzzy torus can be used to approximate a generic commutative torus represented by two generic vectors in the complex plane, with generic modular parameter \\tau. The effective classical geometry and the spectrum of the Laplacian are correctly reproduced in the limit. The spectrum of a matrix Dirac operator is also computed.
Torus palatinus. Report of two cases
Directory of Open Access Journals (Sweden)
María Lorena Re Domínguez
2016-04-01
Full Text Available The torus is a non-neoplastic slow growing bone protuberance, which is usually manifested before the age of 30; Set in the hard palate is called “Torus Palatinus”, and located in the lower jaw – “Torus mandibularis”. In most cases, the diagnosis is usually incidental, during clinical examination, due to other reasons. The reason is that they are usually asymptomatic and patients are not aware of carrying a torus; hence the conservation treatment, unless it poses problems for the patient. We report two cases of incidental detected palatal torus in women.
Torus Actions and Integrable Systems
Zung, Nguyen Tien
2004-01-01
This is a survey on natural local torus actions which arise in integrable dynamical systems, and their relations with other subjects, including: reduced integrability, local normal forms, affine structures, monodromy, global invariants, integrable surgery, convexity properties of momentum maps, localization formulas, integrable PDEs.
Rigidity theorems of Clifford Torus
Directory of Open Access Journals (Sweden)
SOUSA JR. LUIZ A. M.
2001-01-01
Full Text Available Let M be an n-dimensional closed minimally immersed hypersurface in the unit sphere Sn + 1. Assume in addition that M has constant scalar curvature or constant Gauss-Kronecker curvature. In this note we announce that if M has (n - 1 principal curvatures with the same sign everywhere, then M is isometric to a Clifford Torus .
Efficient Subtorus Processor Allocation in a Multi-Dimensional Torus
Energy Technology Data Exchange (ETDEWEB)
Weizhen Mao; Jie Chen; William Watson
2005-11-30
Processor allocation in a mesh or torus connected multicomputer system with up to three dimensions is a hard problem that has received some research attention in the past decade. With the recent deployment of multicomputer systems with a torus topology of dimensions higher than three, which are used to solve complex problems arising in scientific computing, it becomes imminent to study the problem of allocating processors of the configuration of a torus in a multi-dimensional torus connected system. In this paper, we first define the concept of a semitorus. We present two partition schemes, the Equal Partition (EP) and the Non-Equal Partition (NEP), that partition a multi-dimensional semitorus into a set of sub-semitori. We then propose two processor allocation algorithms based on these partition schemes. We evaluate our algorithms by incorporating them in commonly used FCFS and backfilling scheduling policies and conducting simulation using workload traces from the Parallel Workloads Archive. Specifically, our simulation experiments compare four algorithm combinations, FCFS/EP, FCFS/NEP, backfilling/EP, and backfilling/NEP, for two existing multi-dimensional torus connected systems. The simulation results show that our algorithms (especially the backfilling/NEP combination) are capable of producing schedules with system utilization and mean job bounded slowdowns comparable to those in a fully connected multicomputer.
National Spherical Torus Experiment (NSTX) Torus Design, Fabrication and Assembly
Energy Technology Data Exchange (ETDEWEB)
C. Neumeyer; G. Barnes; J.H. Chrzanowski; P. Heitzenroeder; et al
1999-11-01
The National Spherical Torus Experiment (NSTX) is a low aspect ratio spherical torus (ST) located at Princeton Plasma Physics Laboratory (PPPL). Fabrication, assembly, and initial power tests were completed in February of 1999. The majority of the design and construction efforts were constructed on the Torus system components. The Torus system includes the centerstack assembly, external Poloidal and Toroidal coil systems, vacuum vessel, torus support structure and plasma facing components (PFC's). NSTX's low aspect ratio required that the centerstack be made with the smallest radius possible. This, and the need to bake NSTXs carbon-carbon composite plasma facing components at 350 degrees C, was major drivers in the design of NSTX. The Centerstack Assembly consists of the inner legs of the Toroidal Field (TF) windings, the Ohmic Heating (OH) solenoid and its associated tension cylinder, three inner Poloidal Field (PF) coils, thermal insulation, diagnostics and an Inconel casing which forms the inner wall of the vacuum vessel boundary. It took approximately nine months to complete the assembly of the Centerstack. The tight radial clearances and the extreme length of the major components added complexity to the assembly of the Centerstack components. The vacuum vessel was constructed of 304-stainless steel and required approximately seven months to complete and deliver to the Test Cell. Several of the issues associated with the construction of the vacuum vessel were control of dimensional stability following welding and controlling the permeability of the welds. A great deal of time and effort was devoted to defining the correct weld process and material selection to meet our design requirements. The PFCs will be baked out at 350 degrees C while the vessel is maintained at 150 degrees C. This required care in designing the supports so they can accommodate the high electromagnetic loads resulting from plasma disruptions and the resulting relative thermal
NATO Advanced Study Institute on Advanced Physical Oceanographic Numerical Modelling
1986-01-01
This book is a direct result of the NATO Advanced Study Institute held in Banyuls-sur-mer, France, June 1985. The Institute had the same title as this book. It was held at Laboratoire Arago. Eighty lecturers and students from almost all NATO countries attended. The purpose was to review the state of the art of physical oceanographic numerical modelling including the parameterization of physical processes. This book represents a cross-section of the lectures presented at the ASI. It covers elementary mathematical aspects through large scale practical aspects of ocean circulation calculations. It does not encompass every facet of the science of oceanographic modelling. We have, however, captured most of the essence of mesoscale and large-scale ocean modelling for blue water and shallow seas. There have been considerable advances in modelling coastal circulation which are not included. The methods section does not include important material on phase and group velocity errors, selection of grid structures, advanc...
Energy Technology Data Exchange (ETDEWEB)
M. Ono; M. Peng; C. Kessel; C. Neumeyer; J. Schmidt; J. Chrzanowski; D. Darrow; L. Grisham; P. Heitzenroeder; T. Jarboe; C. Jun; S. Kaye; J. Menard; R. Raman; T. Stevenson; M. Viola; J. Wilson; R. Woolley; I. Zatz
2003-10-27
A spherical torus (ST) fusion energy development path which is complementary to proposed tokamak burning plasma experiments such as ITER is described. The ST strategy focuses on a compact Component Test Facility (CTF) and higher performance advanced regimes leading to more attractive DEMO and Power Plant scale reactors. To provide the physics basis for the CTF an intermediate step needs to be taken which we refer to as the ''Next Step Spherical Torus'' (NSST) device and examine in some detail herein. NSST is a ''performance extension'' (PE) stage ST with the plasma current of 5-10 MA, R = 1.5 m, and Beta(sub)T less than or equal to 2.7 T with flexible physics capability. The mission of NSST is to: (1) provide a sufficient physics basis for the design of CTF, (2) explore advanced operating scenarios with high bootstrap current fraction/high performance regimes, which can then be utilized by CTF, DEMO, and Power Plants, and (3) contribute to the general plasma/fusion science of high beta toroidal plasmas. The NSST facility is designed to utilize the Tokamak Fusion Test Reactor (or similar) site to minimize the cost and time required for the design and construction.
Riemann-Hilbert treatment of Liouville theory on the torus
International Nuclear Information System (INIS)
We apply a perturbative technique to study classical Liouville theory on the torus. After mapping the problem on the cut-plane we give the perturbative treatment for a weak source. When the torus reduces to the square the problem is exactly soluble by means of a quadratic transformation in terms of hypergeometric functions. We give general formulas for the deformation of a torus and apply them to the case of the deformation of the square. One can compute the Heun parameter to first order and express the solution in terms of quadratures. In addition, we give, in terms of quadratures of hypergeometric functions, the exact symmetric Green's function on the square on the background generated by a one-point source of arbitrary strength.
The Columbia Non-neutral Torus
International Nuclear Information System (INIS)
Final report for the Columbia Non-neutral Torus. This details the results from the design, construction and initial operation of the Columbia Non-neutral Torus. During the duration of this grant, I designed, built, and operated the Columbia Nonneutral Torus, the world's lowest aspect ratio stellarator, and arguably, the world's simplest stellarator. This demonstrates the ease and robustness of the chosen stellarator design and allowed us to commence the investigation of the physics of non-neutral plasmas confined on magnetic surfaces. These plasmas are unique in many ways and had not previously been studied in a stellarator. Our first results showed that it is possible to confine and study a relatively cold pure electron plasma in a stellarator. We confirmed that the plasma is stable, and that the plasma is reasonably well confined in a stellarator configuration. These results were published in Physics of Plasmas (2006) and Physical Review Letters (2006). They enabled the existing program which is resolving the underlying transport processes in a classical stellarator with intense self-electric fields and enable the next phase of operation, electron-positron plasma physics. During the period of this grant, two students were trained in experimental plasma physics and both received their PhD degrees shortly after the grant terminated. One student is now employed in the financial services industry, the other is a postdoctoral associate at Los Alamos National Laboratory. The chief goals were to build and begin operation of the Columbia Non-neutral Torus. These goals were achieved in the third year of funding. The development of diagnostic methods and the confirmation of stable equilibria were also achieved during the grant period. In summary, the main scientific goals were all met. The main educational goals were also met, as the experiment became the training ground not only for the two aforementioned graduate students but also for a number of undergraduate students
AlZarea BK
2016-01-01
Bader K AlZarea Department of Prosthodontics, College of Dentistry, Al Jouf University, Al Jouf, Kingdom of Saudi Arabia Background: The most remarkable exostoses of the human jaws are torus palatinus (TP) and torus mandibularis (TM). The aim of the present study was to actuate the prevalence of TP and TM in relation to age and sex among the edentulous patients of Saudi Arabia. Methods: The present study included 847 edentulous subjects (458 men and 389 women) ag...
Numerical simulation of torus-driven plasma transport in the Jovian magnetosphere
Yang, Y. S.; Wolf, R. A.; Spiro, R. W.; Hill, T. W.; Dessler, A. J.
1994-01-01
The Rice convection model has been modified for application to the transport of Io-generated plasma through the Jovian magnetosphere. The new code, called the RCM-J, has been used for several ideal-magnetohydrodynamic (MHD) numerical simulations to study how interchange instability causes an initially assumed torus configuration to break up. In simulations that start from a realistic torus configuration but include no energetic particles, the torus disintegrates too quickly (approximately 50 hours). By adding an impounding distribution of energetic particles to suppress the interchange instability, resonable lifetimes were obtained. For cases in which impoundment is insufficient to produce ideal-MHD stability, the torus breaks up predominantly into long fingers, unless the initial condition strongly favors some other geometrical form. If the initial torus has more mass on one side of the planet than the other, fingers form predominatly on the heavy side (which we associate with the active sector). Coriolis force bends the fingers to lag corotation. The simulation results are consistent with the idea that the fingers are formed with a longitudinal thickness that is roughly equal to the latitudinal distance over which the invariant density declines at the outer edges of the initial torus. Our calculations give an average longitudinal distance between plasma fingers of about 15 deg which corresponds to 20 to 30 minutes of rotation of the torus. We point to some Voyager and Ulysses data that are consistent with this scale of torus longitudinal irregularity.
Steady-State Plasmas in KT5D Magnetized Torus
Institute of Scientific and Technical Information of China (English)
ZHU Zhenhua; LIU Wandong; WAN Baonian; ZHAO Yanping; LI Jiangang; YAN Longwen; YANG Qingwei; DING Xuantong; XU Min; YU Yi; WANG Zhijiang; LU Ronghua; WEN Yizhi; YU Changxuan; MA Jinxiu; WAN Shude
2007-01-01
Steady-state plasma generated by electron cyclotron resonance (ECR) wave in the KT5D magnetized torus was studied using a fast high-resolution camera and Langmuir probes. It was found that both the discharge patterns taken by the camera and the plasma parameters measured by the probes were very sensitive to the working gas pressure and the magnetic configuration of the torus both without and with vertical fields. There existed fast vertical motion of the plasma. Tentative discussion is presented about the observed phenomena such as the bright resonance layer at a high gas pressure and the wave absorption mechanism at a low pressure. Further explanations should be found.
International Nuclear Information System (INIS)
A power plant conceptual study (PPCS) has been conducted in the framework of the European fusion programme with the main objective to demonstrate the safety and environmental advantages and the economic viability of fusion power. Power plant models with limited (''near term concepts'') and advanced plasma physics and technological extrapolations (''advanced concepts'') were considered. Two near term plant models were selected, one employing a water cooled lithium-lead (WCLL), and the other one a helium cooled pebble bed (HCPB) blanket. Two variants were also considered for the advanced power plant models, one adopting a liquid metal blanket with a self-cooled lithium-lead breeder zone and a helium cooled steel structure (''dual coolant lithium lead'', DCLL), and the other one a self-cooled lithium-lead (SCLL) blanket with SiCf/SiC composite as structural material. This report provides a detailed documentation of the neutronics design analyses performed as part of the PPCS study for both the near term and advanced power plant models. Main issues are the assessment of the tritium breeding capability, the evaluation of the nuclear power generation and its spatial distribution, and the assessment and optimisation of the shielding performance. The analyses were based on three-dimensional Monte Carlo calculations with the MCNP code using suitable torus sector models developed for the different PPCS plant variants. (orig.)
International Nuclear Information System (INIS)
Thomson scattering measurements of the central electron temperature and density during the plasma current peak have been performed on the MST Reversed Field Pinch (RFP). This Thomson scattering diagnostic was calibrated for absolute electron density measurements. These measurements of Te and ne, when combined with profile assumptions, were used to calculate estimates of energy confinement time (τE) and poloidal beta (βθ). A standard discharge with Ip ∼ 400 kA, F ∼ -0.1, and θ ∼ 1.6 typically exhibited Te ∼ 275 eV, ne ∼ 2.0 x 1013 cm-3, τE ≤ 1 ms, and βθ ≤ 8%. The results of a limited plasma current scaling study did not indicate a strong scaling of Te or τE with Ip. The Thomson scattering diagnostic was used in conjunction with a bolometer, VUV radiation monitor, and edge magnetic coils to study the loss of energy from the plasma. Results indicate that thermal transport from stochastic magnetic fields, particle loss, and radiation are important energy loss processes. The experiments done for this study included an F-scan, a paddle limiter insertion series, and an argon doping series. The plasma maintained a constant βτ during these perturbation experiments, suggesting that increases in one energy loss channel are compensated by drops in other channels and increases in input power to the plasma
Torus Manifolds in Equivariant Complex Bordism
Darby, Alastair
2014-01-01
We restrict geometric tangential equivariant complex $T^n$-bordism to torus manifolds and provide a complete combinatorial description of the appropriate non-commutative ring. We discover, using equivariant $K$-theory characteristic numbers, that the information encoded in the oriented torus graph associated to a stably complex torus manifold completely describes its equivariant bordism class. We also consider the role of omnioriented quasitoric manifolds in this description.
Classification of Sextics of Torus Type
Oka, Mutsuo; Pho, Duc Tai
2002-01-01
In [7], the second author classified configurations of the singularities on tame sextics of torus type. In this paper, we give a complete classification of the singularities on irreducible sextic of torus type, without assuming the tameness of the sextics. We show that there exist 121 configurations and there are 5 pairs and a triple of configurations for which the corresponding moduli spaces coincide, ignoring the respective torus decomposition.
Torus Actions and the Halperin-Carlsson Conjecture
Kamishima, Y.; Nakayama, M.
2012-01-01
We give an affirmative answer to the Halperin-Carlsson conjecture for the homologically injective torus actions on closed manifolds. This class contains holomorphic torus actions on compact Kahler manifolds, torus actions on compact Riemannian flat manifolds.
Pro-torus actions on Poincar\\'e duality spaces
Özkurt, Ali; Dönmez, Doğan
2006-01-01
In this paper, it is shown that some of the results of torus actions on Poincar\\'{e} duality spaces, Borel's dimension formula and topological splitting principle to local weights, hold if `torus' is replaced by `pro-torus'.
Recent progress on spherical torus research
International Nuclear Information System (INIS)
The spherical torus or spherical tokamak (ST) is a member of the tokamak family with its aspect ratio (A = R0/a) reduced to A ∼ 1.5, well below the normal tokamak operating range of A ≥ 2.5. As the aspect ratio is reduced, the ideal tokamak beta β (radio of plasma to magnetic pressure) stability limit increases rapidly, approximately as β ∼ 1/A. The plasma current it can sustain for a given edge safety factor q-95 also increases rapidly. Because of the above, as well as the natural elongation κ, which makes its plasma shape appear spherical, the ST configuration can yield exceptionally high tokamak performance in a compact geometry. Due to its compactness and high performance, the ST configuration has various near term applications, including a compact fusion neutron source with low tritium consumption, in addition to its longer term goal of an attractive fusion energy power source. Since the start of the two mega-ampere class ST facilities in 2000, the National Spherical Torus Experiment in the United States and Mega Ampere Spherical Tokamak in UK, active ST research has been conducted worldwide. More than 16 ST research facilities operating during this period have achieved remarkable advances in all fusion science areas, involving fundamental fusion energy science as well as innovation. These results suggest exciting future prospects for ST research both near term and longer term. The present paper reviews the scientific progress made by the worldwide ST research community during this new mega-ampere-ST era
Penatalaksanaan Torus Palatinus Untuk Persiapan Pembuatan Gigi Tiruan
Maria Fhebyani
2008-01-01
Pengambilan torus palatinus sebelum pembuatan gigi timan dilakukan pada torus palatinus yang besar dengan bentuk tidak teratur atau torus yang meluas sampai ke belakang dan mencapai sebagian palatum lunak, dimana torus seperti itu dapat menghalangi pembuatan penutupan tepi posterior. Persiapan yang penting dilakukan sebelum pengambilan torus palatinus adalah melakukan diagnosa dengan melihat gambaran klinis, yaitu bagaimana bentuk torus palatinus tersebut, dan juga dilakukan pemeriksaan r...
Design innovations of the next-step spherical torus experiment and spherical torus development path
International Nuclear Information System (INIS)
The spherical torus (ST) fusion energy development path is complementary to the tokamak burning plasma experiment such as ITER as it focuses toward the compact Component Test Facility (CTF) and higher toroidal beta regimes to improve the design of DEMO and a Power Plant. To support the ST development path, one option of a Next Step Spherical Torus (NSST) device is examined. NSST is a 'performance extension' (PE) stage ST with a plasma current of 5 - 10 MA, R = 1.5, BT ≤ 2.7 T with flexible physics capability to 1) Provide a sufficient physics basis for the design of the CTF, 2) Explore advanced operating scenarios with high bootstrap current fraction/high performance regimes, which can then be utilized by CTF, DEMO, and Power Plants, 3) Contribute to the general plasma/fusion science of high β toroidal plasmas. The NSST facility is designed to utilize the TFTR site to minimize the cost and time required for the construction. (author)
Tachyon Condensation on Noncommutative Torus
Bars, Itzhak; Matsuo, Y; Takayanagi, T
2001-01-01
We discuss noncommutative solitons on a noncommutative torus and their application to tachyon condensation. In the large B limit, they can be exactly described by the Powers-Rieffel projection operators known in the mathematical literature. The resulting soliton spectrum is consistent with T-duality and is surprisingly interesting. It is shown that an instability arises for any D-branes, leading to the decay into many smaller D-branes. This phenomenon is the consequence of the fact that K-homology for type II von Neumann factor is labeled by R.
International Nuclear Information System (INIS)
This document describes a set of computer programs developed to facilitate storage and retrieval of data generated by the ELMO Bumpy Torus (EBT) experiment. The data is stored in a collection of files which contain either raw or analyzed data from diagnostics connected to the experiment. An on-line index of steady-state machine conditions, diagnostic or analysis status information, and raw or analyzed data values unifies the file collection into a data base. The index is implemented under the System 1022 data base management system
Observations of the Io plasma torus
Lane, A. L.; Moos, H. W.; Clarke, J. T.; Atreya, S. K.
1981-01-01
The short wavelength spectrography on the IUE satellite was used to obtain spectra of the plasma torus near the orbit of Io about Jupiter. Three exposures of about 8 hours each taken in March and May 1979 show emission features due to SII, SIII, and OIII. The absence of features at other wavelengths permits upper limits to be other species in the torus.
Finite covering projections of noncommutative torus
Ivankov, Petr
2014-01-01
This article contains is concerned with noncommutative analogue of topological finitely listed covering projections. In my previous article I have already find a family of covering projections of the noncommutative torus. This article describes all covering projections of the noncommutative torus.
Spherical structures on torus knots and links
Kolpakov, Alexander; Mednykh, Alexander
2010-01-01
The present paper considers two infinite families of cone-manifolds endowed with spherical metric. The singular strata is either the torus knot ${\\rm t}(2n+1, 2)$ or the torus link ${\\rm t}(2n, 2)$. Domains of existence for a spherical metric are found in terms of cone angles and volume formul{\\ae} are presented.
Minimal model correlation functions on the torus
Energy Technology Data Exchange (ETDEWEB)
Bagger, J.; Nemeschansky, D.; Zuber, J.B.
1989-01-12
We generalize the Feigin-Fuchs construction to the torus, and propose an ansatz for certain correlation functions of the minimal conformal models. Our ansatz is periodic, modular-covariant and has the correct short-distance behavior. As an example, we compute the one-point function of the Ising-model energy operator on the torus.
Bifurcation structure of successive torus doubling
Energy Technology Data Exchange (ETDEWEB)
Sekikawa, Munehisa [Department of Information Science, Faculty of Engineering, Utsunomiya University (Japan)]. E-mail: muse@aihara.jst.go.jp; Inaba, Naohiko [Department of Information Science, Faculty of Engineering, Utsunomiya University (Japan)]. E-mail: inaba@is.utsunomiya-u.ac.jp; Yoshinaga, Tetsuya [Department of Radiologic Science and Engineering, School of Health Sciences, The University of Tokushima (Japan)]. E-mail: yosinaga@medsci.tokushima-u.ac.jp; Tsubouchi, Takashi [Institute of Engineering Mechanics and Systems, University of Tsukuba (Japan)]. E-mail: tsubo@esys.tsukuba.ac.jp
2006-01-02
The authors discuss the 'embryology' of successive torus doubling via the bifurcation theory, and assert that the coupled map of a logistic map and a circle map has a structure capable of generating infinite number of torus doublings.
International Nuclear Information System (INIS)
Clearly a new device now ready for construction will be operated during roughly the same period of time as JET and it should therefore be designed as a useful complement to JET with the aim of preparing for the next phase of the programme. A number of prospective studies, in particular the Long Term Planning and the work on INTOR and NET have pointed out several fields where a large effort was needed. In some of these fields the EURATOM-C.E.A. Association is especially well prepared to bring important contributions and this is the case for: - the construction and operation of a super conducting Tokamak, - the development of Radio Frequency Heating. These two subjects have been chosen as the major items of the proposed programme. In addition the existing expertise in Tokamak physics and the characteristics of the device lead to propose two other subjects of work, namely: - the dynamics of impurities, - the study of long pulses
Advance in MEIC cooling studies
Energy Technology Data Exchange (ETDEWEB)
Zhang, Yuhong [JLAB, Newport News, VA (United States); Derbenev, Ya. [JLAB, Newport News, VA (United States); Douglas, D. [JLAB, Newport News, VA (United States); Hutton, A. [JLAB, Newport News, VA (United States); Kimber, A. [JLAB, Newport News, VA (United States); Li, R. [JLAB, Newport News, VA (United States); Nissen, E. [JLAB, Newport News, VA (United States); Tennant, [JLAB, Newport News, VA (United States); Zhang, H. [JLAB, Newport News, VA (United States)
2013-06-01
Cooling of ion beams is essential for achieving a high luminosity for MEIC at Jefferson Lab. In this paper, we present the design concept of the electron cooling system for MEIC. In the design, two facilities are required for supporting a multi-staged cooling scheme; one is a 2 MeV DC cooler in the ion pre-booster; the other is a high electron energy (up to 55 MeV) ERL-circulator cooler in the collider ring. The simulation studies of beam dynamics in an ERL-circulator cooler are summarized and followed by a report on technology development for this cooler. We also discuss two proposed experiments for demonstrating high energy cooling with a bunched electron beam and the ERL-circulator cooler.
National Spherical Torus Experiment (NSTX)
International Nuclear Information System (INIS)
The main aim of National Spherical Torus Experiment (NSTX) is to establish the fusion physics principles of the innovative spherical torus (ST) concept. Physics outcome of the NSTX research program is relevant to near-term applications such as the Volume Neutron Source (VNS) and burning plasmas, and future applications such as the pilot and power plants. The NSTX device began plasma operations in February 1999 and the plasma current was successfully ramped up to the design value of 1 million amperes (MA) on December 14, 1999. The CHI (Coaxial Helicity Injection) and HHFW (High Harmonic Fast Wave) experiments have also started. Stable CHI discharges of up to 133 kA and 130-msec duration have been produced using 20 kA of injected current. Using eight antennas connected to two transmitters, up to 2 MW of HHFW power was successfully coupled to the plasma. The Neutral-beam Injection (NBI) heating system and associated NBI-based diagnostics such as the Charge-exchange Recombination Spectrometer (CHERS) will be operational in October 2000
Charged particle driver for ICF using an accelerated, focused compact torus
International Nuclear Information System (INIS)
We report the status of evaluating an accelerated and focused compact torus as a driver for ICF. We are studying the acceleration and focusing aspects experimentally in the RACE facility, a recently completed ring generator coupled to a 260 kJ acceleration bank. Compact torus and ICF target interaction is being investigated with PIC codes and LASNEX, a 2D magneto-hydrodynamics code. Final conditions required of the CT are discussed as well as coupling issues such as superthermal electron production. We conclude with an economic evaluation of a few 100 MW reactor driven by a compact torus. 9 refs., 5 figs., 1 tab
Computation of Quantum Bound States on a Singly Punctured Two-Torus
International Nuclear Information System (INIS)
We study a quantum mechanical system on a singly punctured two-torus with bound states described by the Maass waveforms which are eigenfunctions of the hyperbolic Laplace—Beltrami operator. Since the discrete eigenvalues of the Maass cusp form are not known analytically, they are solved numerically using an adapted algorithm of Hejhal and Then to compute Maass cusp forms on the punctured two-torus. We report on the computational results of the lower lying eigenvalues for the punctured two-torus and find that they are doubly-degenerate. We also visualize the eigenstates of selected eigenvalues using GridMathematica
Advanced Cogeneration Technology Economic Optimization Study (ACTEOS)
Nanda, P.; Ansu, Y.; Manuel, E. H., Jr.; Price, W. G., Jr.
1980-01-01
The advanced cogeneration technology economic optimization study (ACTEOS) was undertaken to extend the results of the cogeneration technology alternatives study (CTAS). Cost comparisons were made between designs involving advanced cogeneration technologies and designs involving either conventional cogeneration technologies or not involving cogeneration. For the specific equipment cost and fuel price assumptions made, it was found that: (1) coal based cogeneration systems offered appreciable cost savings over the no cogeneration case, while systems using coal derived liquids offered no costs savings; and (2) the advanced cogeneration systems provided somewhat larger cost savings than the conventional systems. Among the issues considered in the study included: (1) temporal variations in steam and electric demands; (2) requirements for reliability/standby capacity; (3) availability of discrete equipment sizes; (4) regional variations in fuel and electricity prices; (5) off design system performance; and (6) separate demand and energy charges for purchased electricity.
Progress towards high-performance, steady-state spherical torus.
Energy Technology Data Exchange (ETDEWEB)
Lee, S.G (Korea Basic Science Institute, Taejon, Republic of Korea); Kugel, W. (Princeton University, NJ); Efthimion, P. C. (Princeton University, NJ); Kissick, M. W. (University of Wisconsin, WI); Bourdelle, C. (CEA Cadarache, France); Kim, J.H (Korea Advanced Institute of Science and Technology, Taejon, Republic of Korea); Gray, T. (Princeton University, NJ); Garstka, G. D. (University of Wisconsin, WI); Fonck, R. J. (University of Wisconsin, WI); Doerner, R. (University of California, San Diego, CA); Diem, S.J. (University of Wisconsin, WI); Pacella, D. (ENEA, Frascati, Italy); Nishino, N. (Hiroshima University, Hiroshima, Japan); Ferron, J. R. (General Atomics, San Diego, CA); Skinner, C. H. (Princeton University, NJ); Stutman, D. (Johns Hopkins University, Baltimore, MD); Soukhanovskii, V. (Princeton University, NJ); Choe, W. (Korea Advanced Institute of Science and Technology, Taejon, Republic of Korea); Chrzanowski, J. (Princeton University, NJ); Mau, T.K. (University of California, San Diego, CA); Bell, Michael G. (Princeton University, NJ); Raman, R. (University of Washington, Seattle, WA); Peng, Y-K. M. (Oak Ridge National Laboratory, Oak Ridge, TN); Ono, M. (Princeton University, NJ); Park, W. (Princeton University, NJ); Hoffman, D. (Princeton University, NJ); Maqueda, R. (Los Alamos National Laboratory, Los Alamos, NM); Kaye, S. M. (Princeton University, NJ); Kaita, R. (Princeton University, NJ); Jarboe, T.R. (University of Washington, Seattle, WA); Hill, K.W. (Princeton University, NJ); Heidbrink, W. (University of California, Irvine, CA); Spaleta, J. (Princeton University, NJ); Sontag, A.C (University of Wisconsin, WI); Seraydarian, R. (University of California, San Diego, CA); Schooff, R.J. (University of Wisconsin, WI); Sabbagh, S.A. (Columbia University, New York, NY); Menard, J. (Princeton University, NJ); Mazzucato, E. (Princeton University, NJ); Lee, K. (University of California, Davis, CA); LeBlanc, B. (Princeton University, NJ); Probert, P. H. (University of Wisconsin, WI); Blanchard, W. (Princeton University, NJ); Wampler, William R.; Swain, D. W. (Oak Ridge National Laboratory, Oak Ridge, TN); Ryan, P.M. (Oak Ridge National Laboratory, Oak Ridge, TN); Rosenberg, A. (Princeton University, NJ); Ramakrishnan, S. (Princeton University, NJ); Phillips, C.K. (Princeton University, NJ); Park, H.K. (Princeton University, NJ); Roquemore, A. L. (Princeton University, NJ); Paoletti, F. (Columbia University, New York, NY); Medley, S. S. (Princeton University, NJ); Fredrickson, E. D. (Princeton University, NJ); Kessel, C. E. (Princeton University, NJ); Stevenson, T. (Princeton University, NJ); Darrow, D. S. (Princeton University, NJ); Majeski, R. (Princeton University, NJ); Bitter, M. (Princeton University, NJ); Neumeyer, C. (Princeton University, NJ); Nelson, B.A. (University of Washington, Seattle, WA); Paul, S. F. (Princeton University, NJ); Manickam, J. (Princeton University, NJ); Ostrander, C. N. (University of Wisconsin, WI); Mueller, D. (Princeton University, NJ); Lewicki, B.T (University of Wisconsin, WI); Luckhardt, S. (University of California, San Diego, CA); Johnson, D.W. (Princeton University, NJ); Grisham, L.R. (Princeton University, NJ); Kubota, Shigeru (University of California, Los Angeles, CA); Gates, D.A. (Princeton University, NJ); Bush, C. (Oak Ridge National Laboratory, Oak Ridge, TN); Synakowski, E.J. (Princeton University, NJ); Schaffer, M. (General Atomics, San Diego, CA); Boedo, J. (University of California, San Diego, CA); Maingi, R. (Oak Ridge National Laboratory, Oak Ridge, TN); Redi, M. (Princeton University, NJ); Pinsker, R. (General Atomics, San Diego, CA); Bigelow, T. (Oak Ridge National Laboratory, Oak Ridge, TN); Bell, R. E. (Princeton University, NJ)
2004-06-01
Research on the spherical torus (or spherical tokamak) (ST) is being pursued to explore the scientific benefits of modifying the field line structure from that in more moderate aspect ratio devices, such as the conventional tokamak. The ST experiments are being conducted in various US research facilities including the MA-class National Spherical Torus Experiment (NSTX) at Princeton, and three medium sized ST research facilities: PEGASUS at University of Wisconsin, HIT-II at University of Washington, and CDX-U at Princeton. In the context of the fusion energy development path being formulated in the US, an ST-based Component Test Facility (CTF) and, ultimately a Demo device, are being discussed. For these, it is essential to develop high performance, steady-state operational scenarios. The relevant scientific issues are energy confinement, MHD stability at high beta ({beta}), non-inductive sustainment, Ohmic-solenoid-free start-up, and power and particle handling. In the confinement area, the NSTX experiments have shown that the confinement can be up to 50% better than the ITER-98-pby2 H-mode scaling, consistent with the requirements for an ST-based CTF and Demo. In NSTX, CTF-relevant average toroidal beta values {beta}{sub T} of up to 35% with a near unity central {beta}{sub T} have been obtained. NSTX will be exploring advanced regimes where {beta}{sub T} up to 40% can be sustained through active stabilization of resistive wall modes. To date, the most successful technique for non-inductive sustainment in NSTX is the high beta poloidal regime, where discharges with a high non-inductive fraction ({approx}60% bootstrap current+NBI current drive) were sustained over the resistive skin time. Research on radio-frequency (RF) based heating and current drive utilizing high harmonic fast wave and electron Bernstein wave is also pursued on NSTX, PEGASUS, and CDX-U. For non-inductive start-up, the coaxial helicity injection, developed in HIT/HIT-II, has been adopted on NSTX
Progress Towards High Performance, Steady-state Spherical Torus
Energy Technology Data Exchange (ETDEWEB)
M. Ono; M.G. Bell; R.E. Bell; T. Bigelow; M. Bitter; W. Blanchard; J. Boedo; C. Bourdelle; C. Bush; W. Choe; J. Chrzanowski; D.S. Darrow; S.J. Diem; R. Doerner; P.C. Efthimion; J.R. Ferron; R.J. Fonck; E.D. Fredrickson; G.D. Garstka; D.A. Gates; T. Gray; L.R. Grisham; W. Heidbrink; K.W. Hill; D. Hoffman; T.R. Jarboe; D.W. Johnson; R. Kaita; S.M. Kaye; C. Kessel; J.H. Kim; M.W. Kissick; S. Kubota; H.W. Kugel; B.P. LeBlanc; K. Lee; S.G. Lee; B.T. Lewicki; S. Luckhardt; R. Maingi; R. Majeski; J. Manickam; R. Maqueda; T.K. Mau; E. Mazzucato; S.S. Medley; J. Menard; D. Mueller; B.A. Nelson; C. Neumeyer; N. Nishino; C.N. Ostrander; D. Pacella; F. Paoletti; H.K. Park; W. Park; S.F. Paul; Y.-K. M. Peng; C.K. Phillips; R. Pinsker; P.H. Probert; S. Ramakrishnan; R. Raman; M. Redi; A.L. Roquemore; A. Rosenberg; P.M. Ryan; S.A. Sabbagh; M. Schaffer; R.J. Schooff; R. Seraydarian; C.H. Skinner; A.C. Sontag; V. Soukhanovskii; J. Spaleta; T. Stevenson; D. Stutman; D.W. Swain; E. Synakowski; Y. Takase; X. Tang; G. Taylor; J. Timberlake; K.L. Tritz; E.A. Unterberg; A. Von Halle; J. Wilgen; M. Williams; J.R. Wilson; X. Xu; S.J. Zweben; R. Akers; R.E. Barry; P. Beiersdorfer; J.M. Bialek; B. Blagojevic; P.T. Bonoli; M.D. Carter; W. Davis; B. Deng; L. Dudek; J. Egedal; R. Ellis; M. Finkenthal; J. Foley; E. Fredd; A. Glasser; T. Gibney; M. Gilmore; R.J. Goldston; R.E. Hatcher; R.J. Hawryluk; W. Houlberg; R. Harvey; S.C. Jardin; J.C. Hosea; H. Ji; M. Kalish; J. Lowrance; L.L. Lao; F.M. Levinton; N.C. Luhmann; R. Marsala; D. Mastravito; M.M. Menon; O. Mitarai; M. Nagata; G. Oliaro; R. Parsells; T. Peebles; B. Peneflor; D. Piglowski; G.D. Porter; A.K. Ram; M. Rensink; G. Rewoldt; P. Roney; K. Shaing; S. Shiraiwa; P. Sichta; D. Stotler; B.C. Stratton; R. Vero; W.R. Wampler; G.A. Wurden
2003-10-02
Research on the Spherical Torus (or Spherical Tokamak) is being pursued to explore the scientific benefits of modifying the field line structure from that in more moderate aspect-ratio devices, such as the conventional tokamak. The Spherical Tours (ST) experiments are being conducted in various U.S. research facilities including the MA-class National Spherical Torus Experiment (NSTX) at Princeton, and three medium-size ST research facilities: Pegasus at University of Wisconsin, HIT-II at University of Washington, and CDX-U at Princeton. In the context of the fusion energy development path being formulated in the U.S., an ST-based Component Test Facility (CTF) and, ultimately a Demo device, are being discussed. For these, it is essential to develop high-performance, steady-state operational scenarios. The relevant scientific issues are energy confinement, MHD stability at high beta (B), noninductive sustainment, ohmic-solenoid-free start-up, and power and particle handling. In the confinement area, the NSTX experiments have shown that the confinement can be up to 50% better than the ITER-98-pby2 H-mode scaling, consistent with the requirements for an ST-based CTF and Demo. In NSTX, CTF-relevant average toroidal beta values bT of up to 35% with the near unity central betaT have been obtained. NSTX will be exploring advanced regimes where bT up to 40% can be sustained through active stabilization of resistive wall modes. To date, the most successful technique for noninductive sustainment in NSTX is the high beta-poloidal regime, where discharges with a high noninductive fraction ({approx}60% bootstrap current + neutral-beam-injected current drive) were sustained over the resistive skin time. Research on radio-frequency-based heating and current drive utilizing HHFW (High Harmonic Fast Wave) and EBW (Electron Bernstein Wave) is also pursued on NSTX, Pegasus, and CDX-U. For noninductive start-up, the Coaxial Helicity Injection (CHI), developed in HIT/HIT-II, has been
Progress towards high-performance, steady-state spherical torus
Energy Technology Data Exchange (ETDEWEB)
Ono, M.; Bell, M. G.; Bell, R. E.; Bigelow, T.; Bitter, M.; Blanchard, W.; Boedo, J.; Bourdelle, C.; Bush, C.; Choe, W.; Chrzanowski, J.; Darrow, D. S.; Diem, S. J.; Doerner, R.; Efthimion, P. C.; Ferron, J. R.; Fonck, R. J.; Fredrickson, E. D.; Garstka, G. D.; Gates, D A; Gray, T.; Grisham, L. R.; Heidbrink, W.; Hill, K. W.; Hoffman, D.; Jarboe, T. R.; Johnson, D. W.; Kaita, R.; Kaye, S. M.; Kessel, C.; Kim, J. H.; Kissick, M. W.; Kubota, S.; Kugel, H. W.; LeBlanc, B. P.; Lee, K.; Lee, S. G.; Lewicki, B. T.; Luckhardt, S.; Maingi, R.; Majeski, R.; Manickam, J.; Maqueda, R.; Mau, T. K.; Mazzucato, E.; Medley, S. S.; Menard, J.; Mueller, D.; Nelson, B. A.; Neumeyer, C.; Nishino, N.; Ostrander, C. N.; Pacella, D.; Paoletti, F.; Park, H. K.; Park, W.; Paul, S. F.; Peng, Y-K M.; Phillips, C. K.; Pinsker, R.; Probert, P. H.; Ramakrishnan, S.; Raman, R.; Redi, M.; Roquemore, A. L.; Rosenberg, A.; Ryan, P. M.; Sabbagh, S. A.; Schaffer, M.; Schooff, R. J.; Seraydarian, R.; Skinner, C. H.; Sontag, A. C.; Soukhanovskii, V.; Spaleta, J.; Stevenson, T.; Stutman, D.; Swain, D. W.; Synakowski, E.; Takase, Y.; Tang, X.; Taylor, G.; Timberlake, J.; Tritz, K. L.; Unterberg, E. A.; Halle, A. Von.; Wilgen, J.; Williams, M.; Wilson, J. R.; Xu, X.; Zweben, S. J.; Akers, R.; Barry, R. E.; Beiersdorfer, P.; Bialek, J. M.; Blagojevic, B.; Bonoli, P. T.; Carter, M. D.; Davis, W.; Deng, B.; Dudek, L.; Egedal, J.; Ellis, R.; Finkenthal, M.; Foley, J.; Fredd, E.; Glasser, A.; Gibney, T.; Gilmore, M.; Goldston, R. J.; Hatcher, R. E.; Hawryluk, R. J.; Houlberg, W.; Harvey, R.; Jardin, S. C.; Hosea, J. C.; Ji, H.; Kalish, M.; Lowrance, J.; Lao, L. L.; Levinton, F. M.; Luhmann, N. C.; Marsala, R.; Mastravito, D.; Menon, M. M.; Mitarai, O.; Nagata, M.; Oliaro, G.; Parsells, R.; Peebles, T.; Peneflor, B.; Piglowski, D.; Porter, G. D.; Ram, A. K.; Rensink, M.; Rewoldt, G.; Robinson, J.; Roney, P.; Shaing, K.; Shiraiwa, S.; Sichta, P.; Stotler, D.; Stratton, B. C.; Vero, R.; Wampler, W. R.; Wurden, G. A.
2003-12-01
Research on the spherical torus (or spherical tokamak) (ST) is being pursued to explore the scientific benefits of modifying the field line structure from that in more moderate aspect ratio devices, such as the conventional tokamak. The ST experiments are being conducted in various US research facilities including the MA-class National Spherical Torus Experiment (NSTX) at Princeton, and three medium sized ST research facilities: PEGASUS at University of Wisconsin, HIT-II at University of Washington, and CDX-U at Princeton. In the context of the fusion energy development path being formulated in the US, an ST-based Component Test Facility (CTF) and, ultimately a Demo device, are being discussed. For these, it is essential to develop high performance, steady-state operational scenarios. The relevant scientific issues are energy confinement, MHD stability at high beta (β), non-inductive sustainment, Ohmic-solenoid-free start-up, and power and particle handling. In the confinement area, the NSTX experiments have shown that the confinement can be up to 50% better than the ITER-98-pby2 H-mode scaling, consistent with the requirements for an ST-based CTF and Demo. In NSTX, CTF-relevant average toroidal beta values β_{T} of up to 35% with a near unity central β_{T} have been obtained. NSTX will be exploring advanced regimes where β_{T} up to 40% can be sustained through active stabilization of resistive wall modes. To date, the most successful technique for non-inductive sustainment in NSTX is the high beta poloidal regime, where discharges with a high non-inductive fraction (~ 60% bootstrap current+NBI current drive) were sustained over the resistive skin time. Research on radio-frequency (RF) based heating and current drive utilizing high harmonic fast wave and electron Bernstein wave is also pursued on NSTX, PEGASUS, and CDX-U. For non-inductive start-up, the coaxial helicity injection, developed in HIT/HIT-II, has been adopted on NSTX to
Progress Towards High-Performance, Steady-State Spherical Torus
Energy Technology Data Exchange (ETDEWEB)
Lawrence Livermore National Laboratory
2004-01-04
Research on the spherical torus (or spherical tokamak) (ST) is being pursued to explore the scientific benefits of modifying the field line structure from that in more moderate aspect ratio devices, such as the conventional tokamak. The ST experiments are being conducted in various US research facilities including the MA-class National Spherical Torus Experiment (NSTX) at Princeton, and three medium sized ST research facilities: PEGASUS at University of Wisconsin, HIT-II at University of Washington, and CDX-U at Princeton. In the context of the fusion energy development path being formulated in the US, an ST-based Component Test Facility (CTF) and, ultimately a Demo device, are being discussed. For these, it is essential to develop high performance, steady-state operational scenarios. The relevant scientific issues are energy confinement, MHD stability at high beta ({beta}), non-inductive sustainment, Ohmic-solenoid-free start-up, and power and particle handling. In the confinement area, the NSTX experiments have shown that the confinement can be up to 50% better than the ITER-98-pby2 H-mode scaling, consistent with the requirements for an ST-based CTF and Demo. In NSTX, CTF-relevant average toroidal beta values {beta}{sub T} of up to 35% with a near unity central {beta}{sub T} have been obtained. NSTX will be exploring advanced regimes where {beta}{sub T} up to 40% can be sustained through active stabilization of resistive wall modes. To date, the most successful technique for non-inductive sustainment in NSTX is the high beta poloidal regime, where discharges with a high non-inductive fraction ({approx}60% bootstrap current+NBI current drive) were sustained over the resistive skin time. Research on radio-frequency (RF) based heating and current drive utilizing high harmonic fastwave and electron Bernstein wave is also pursued on NSTX, PEGASUS, and CDX-U. For non-inductive start-up, the coaxial helicity injection, developed in HIT/HIT-II, has been adopted on NSTX
Progress Towards High Performance, Steady-state Spherical Torus
International Nuclear Information System (INIS)
Research on the Spherical Torus (or Spherical Tokamak) is being pursued to explore the scientific benefits of modifying the field line structure from that in more moderate aspect-ratio devices, such as the conventional tokamak. The Spherical Tours (ST) experiments are being conducted in various U.S. research facilities including the MA-class National Spherical Torus Experiment (NSTX) at Princeton, and three medium-size ST research facilities: Pegasus at University of Wisconsin, HIT-II at University of Washington, and CDX-U at Princeton. In the context of the fusion energy development path being formulated in the U.S., an ST-based Component Test Facility (CTF) and, ultimately a Demo device, are being discussed. For these, it is essential to develop high-performance, steady-state operational scenarios. The relevant scientific issues are energy confinement, MHD stability at high beta (B), noninductive sustainment, ohmic-solenoid-free start-up, and power and particle handling. In the confinement area, the NSTX experiments have shown that the confinement can be up to 50% better than the ITER-98-pby2 H-mode scaling, consistent with the requirements for an ST-based CTF and Demo. In NSTX, CTF-relevant average toroidal beta values bT of up to 35% with the near unity central betaT have been obtained. NSTX will be exploring advanced regimes where bT up to 40% can be sustained through active stabilization of resistive wall modes. To date, the most successful technique for noninductive sustainment in NSTX is the high beta-poloidal regime, where discharges with a high noninductive fraction (∼60% bootstrap current + neutral-beam-injected current drive) were sustained over the resistive skin time. Research on radio-frequency-based heating and current drive utilizing HHFW (High Harmonic Fast Wave) and EBW (Electron Bernstein Wave) is also pursued on NSTX, Pegasus, and CDX-U. For noninductive start-up, the Coaxial Helicity Injection (CHI), developed in HIT/HIT-II, has been adopted
TORUS: Theory of Reactions for Unstable iSotopes - Year 1 Continuation and Progress Report
Energy Technology Data Exchange (ETDEWEB)
Arbanas, G; Elster, C; Escher, J; Mukhamedzhanov, A; Nunes, F; Thompson, I J
2011-02-24
The TORUS collaboration derives its name from the research it focuses on, namely the Theory of Reactions for Unstable iSotopes. It is a Topical Collaboration in Nuclear Theory, and funded by the Nuclear Theory Division of the Office of Nuclear Physics in the Office of Science of the Department of Energy. The funding started on June 1, 2010, it will have been running for nine months by the date of submission of this Annual Continuation and Progress Report on March 1, 2011. The extent of funding was reduced from the original application, and now supports one postdoctoral researcher for the years 1 through 3. The collaboration brings together as Principal Investigators a large fraction of the nuclear reaction theorists currently active within the USA. The mission of the TORUS Topical Collaboration is to develop new methods that will advance nuclear reaction theory for unstable isotopes by using three-body techniques to improve direct-reaction calculations, and, by using a new partial-fusion theory, to integrate descriptions of direct and compound-nucleus reactions. This multi-institution collaborative effort is directly relevant to three areas of interest: the properties of nuclei far from stability; microscopic studies of nuclear input parameters for astrophysics, and microscopic nuclear reaction theory.
Energy Technology Data Exchange (ETDEWEB)
Arbanas, Goran [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Elster, Charlotte [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Escher, Jutta [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Nunes, Filomena [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Thompson, Ian [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
2015-08-28
The work of this collaboration during its existence is summarized. The mission of the TORUS Topical Collaboration was to develop new methods that advance nuclear reaction theory for unstable isotopes by using three-body techniques to improve direct reaction calculations. This multi-institution collaborative effort was and remains directly relevant to three areas of interest: the properties of nuclei far from stability, microscopic studies of nuclear input parameters for astrophysics, and microscopic nuclear reaction theory. The TORUS project focused on understanding the details of (d,p) reactions for neutron transfer to heavier nuclei. The bulk of the work fell into three areas: coupled channel theory, modeling (d,p) reactions with a Faddeev-AGS approach, and capture reactions.
International Nuclear Information System (INIS)
The work of this collaboration during its existence is summarized. The mission of the TORUS Topical Collaboration was to develop new methods that advance nuclear reaction theory for unstable isotopes by using three-body techniques to improve direct reaction calculations. This multi-institution collaborative effort was and remains directly relevant to three areas of interest: the properties of nuclei far from stability, microscopic studies of nuclear input parameters for astrophysics, and microscopic nuclear reaction theory. The TORUS project focused on understanding the details of (d,p) reactions for neutron transfer to heavier nuclei. The bulk of the work fell into three areas: coupled channel theory, modeling (d,p) reactions with a Faddeev-AGS approach, and capture reactions.
Local torus actions modeled on the standard representation
Yoshida, Takahiko
2007-01-01
We introduce the notion of a local torus action modeled on the standard representation (for simplicity, we call it a local torus action). It is a generalization of a locally standard torus action and also an underlying structure of a locally toric Lagrangian fibration. For a local torus action, we define two invariants called a characteristic pair and an Euler class of the orbit map, and prove that local torus actions are classified topologically by them. As a corollary, we obtain a topologic...
Advanced Subsonic Airplane Design and Economic Studies
Liebeck, Robert H.; Andrastek, Donald A.; Chau, Johnny; Girvin, Raquel; Lyon, Roger; Rawdon, Blaine K.; Scott, Paul W.; Wright, Robert A.
1995-01-01
A study was made to examine the effect of advanced technology engines on the performance of subsonic airplanes and provide a vision of the potential which these advanced engines offered. The year 2005 was selected as the entry-into-service (EIS) date for engine/airframe combination. A set of four airplane classes (passenger and design range combinations) that were envisioned to span the needs for the 2005 EIS period were defined. The airframes for all classes were designed and sized using 2005 EIS advanced technology. Two airplanes were designed and sized for each class: one using current technology (1995) engines to provide a baseline, and one using advanced technology (2005) engines. The resulting engine/airframe combinations were compared and evaluated on the basis on sensitivity to basic engine performance parameters (e.g. SFC and engine weight) as well as DOC+I. The advanced technology engines provided significant reductions in fuel burn, weight, and wing area. Average values were as follows: reduction in fuel burn = 18%, reduction in wing area = 7%, and reduction in TOGW = 9%. Average DOC+I reduction was 3.5% using the pricing model based on payload-range index and 5% using the pricing model based on airframe weight. Noise and emissions were not considered.
NATO Advanced Study Institute on Advances in Microlocal Analysis
1986-01-01
The 1985 Castel vecchio-Pas coli NATO Advanced Study Institute is aimed to complete the trilogy with the two former institutes I organized : "Boundary Value Problem for Evolution Partial Differential Operators", Liege, 1976 and "Singularities in Boundary Value Problems", Maratea, 1980. It was indeed necessary to record the considerable progress realized in the field of the propagation of singularities of Schwartz Distri butions which led recently to the birth of a new branch of Mathema tical Analysis called Microlocal Analysis. Most of this theory was mainly built to be applied to distribution solutions of linear partial differential problems. A large part of this institute still went in this direction. But, on the other hand, it was also time to explore the new trend to use microlocal analysis In non linear differential problems. I hope that the Castelvecchio NATO ASI reached its purposes with the help of the more famous authorities in the field. The meeting was held in Tuscany (Italy) at Castelvecchio-P...
Torus quantum vortex knots in the Gross-Pitaevskii model for Bose-Einstein condensates
International Nuclear Information System (INIS)
We examine the static and dynamic properties of quantum knots in a Bose-Einstein condensate. In particular, we consider the Gross-Pitaevskii model and revise a technique to construct ab initio the condensate wave-function of a generic torus knot. After analysing its excitation energy, we study its dynamics, relating the topological parameter to its translational velocity and characteristic size. We also investigate the breaking mechanisms of non shapepreserving torus knots, confirming an evidence of universal decaying behaviour previously observed
Analytical model for the density distribution in the Io plasma torus
Mei, YI; Thorne, Richard M.; Bagenal, Fran
1995-01-01
An analytical model is developed for the diffusive equilibrium plasma density distribution in the Io plasma torus. The model has been employed successfully to follow the ray path of plasma waves in the multi-ion Jovian magnetosphere; it would also be valuable for other studies of the Io torus that require a smooth and continuous description of the plasma density and its gradients. Validity of the analytical treatment requires that the temperature of thermal electrons be much lower than the ion temperature and that superthermal electrons be much less abundant than the thermal electrons; these two conditions are satisfied in the warm outer region of the Io torus from L = 6 to L = 10. The analytical solutions agree well with exact numerical calculations for the most dense portion of the Io torus within 30 deg of the equator.
Advances and challenges in innovation studies
Castellacci, F.; Grodal, S.; Mendonça, S; Wibe, M.
2005-01-01
The article discusses recent advances and future challenges in innovation studies. First, it separately considers four main strands of research, studying innovation at the organizational, systemic, sectoral and macroeconomic levels. Then, considering the field as a whole, the article points to the existence of important neglected topics and methodological challenges for future research. In fact, several fundamental issues are still unexplored, such as the co-evolution betwee...
Morita "equivalences" of equivariant torus spectral triples
Venselaar, Jan Jitse
2011-01-01
In general, Morita equivalence of spectral triples need not be a symmetric relation. In this paper, we show that Morita equivalence of spectral triples is an equivalence relation for equivariant torus spectral triples.
Torus bifurcations in multilevel converter systems
DEFF Research Database (Denmark)
Zhusubaliyev, Zhanybai T.; Mosekilde, Erik; Yanochkina, Olga O.
2011-01-01
embedded one into the other and with their basins of attraction delineated by intervening repelling tori. The paper illustrates the coexistence of three stable tori with different resonance behaviors and shows how reconstruction of these tori takes place across the borders of different dynamical regimes....... The paper also demonstrates how pairs of attracting and repelling tori emerge through border-collision torus-birth and border-collision torus-fold bifurcations. © 2011 World Scientific Publishing Company....
Torus destruction in a nonsmooth noninvertible map
International Nuclear Information System (INIS)
We consider here a nonsmooth noninvertible map and report new route to chaos from a resonance loop torus which is not homeomorphic to circle but only endomorphic to it. We have found that cusp torus cannot develop before the onset of chaos, though the loop torus appears. The destruction of the loop torus occurs through homoclinic bifurcation in the presence of an infinite number of nonsmooth loops. We show that owing to the nonsmooth noninvertible nature of the map, the stable sets can bifurcate to form nonsmooth closed loops. However, that cannot be interpreted directly as basin bifurcation. -- Highlights: ► We consider a nonsmooth map which is noninvertible. ► We report a new route to chaos from a resonance loop torus which is not homeomorphic to a circle but only endomorphic to it. ► The destruction of the torus occurs through homoclinic bifurcation in the presence of an infinite number of nonsmooth loops. ► The stable sets can bifurcate to form nonsmooth closed loops. ► The bifurcation of the stable sets cannot be interpreted directly as bifurcation of the basin of attraction.
Io's neutral clouds: From the atmosphere to the plasma torus
Burger, Matthew Howard
2003-10-01
Since the discovery of sodium thirty years ago, observations of Io's neutral features have provided essential insight into understanding the relationship between the Io's atmosphere and the Io torus, a ring of plasma encircling Jupiter. In this thesis I use observations and models of lo's corona, extended neutral clouds, and fast sodium jet to probe the interactions between the atmosphere, torus, and neutral clouds. A corona and neutral cloud model, based on the model of Wilson and Schneider (1999), has been developed to study neutral loss from Io. Neutrals are ejected from Io's exobase and their trajectories followed under the influence of gravity until lost into the plasma torus. I also developed description of the plasma torus based on Voyager and ground-based observations to accurately determine neutral lifetimes. Mutual eclipsing events between Galilean satellites were used to measure the shape of lo's sodium corona, revealing a corona that is only approximately spherically symmetric around Io. I discovered a previously undetected asymmetry: the sub-Jupiter corona is denser than the anti-Jupiter corona. Modeling implies that sodium source from the sub-Jupiter hemisphere must be twice as large as from the anti-Jupiter hemisphere. The Galileo spacecraft has imaged a remarkable atmospheric escape process occurring in Io's ionosphere. Electrodynamic consequences of Io's motion through Jupiter's magnetosphere drive mega-amp currents through lo's ionosphere; some sodium ions carrying this current are neutralized as they leave the atmosphere. The Galileo images show that the resulting fast sodium jet removes ˜5 × 1025 atoms sec-1 from Io's atmosphere. The source region of the jet is much smaller than Io itself implying that the ionosphere is densest near Io's equator. A model-based comparison of the neutral oxygen and sodium clouds details differences in the morphologies and spatial extent of each: sodium extends only 1/4 the way around Jupiter while oxygen forms a
Advanced Cell Development and Degradation Studies
Energy Technology Data Exchange (ETDEWEB)
J. E. O' Brien; C. M. Stoots; J. S. Herring; R. C. O' Brien; K. G. Condie; M. Sohal; G. K. Housley; J. J. Hartvigsen; D. Larsen; G. Tao; B. Yildiz; V. Sharma; P. Singh; N. Petigny; T. L. Cable
2010-09-01
The Idaho National Laboratory (INL) has been researching the application of solid-oxide electrolysis cells for large-scale hydrogen production from steam over a temperature range of 800 to 900ºC. From 2003 – 2009, this work was sponsored by the DOE Nuclear Hydrogen Initiative (NHI). Starting in 2010, the HTE research program has been sponsored by the Next Generation Nuclear Plant (NGNP) program. HTSE research priorities in FY10 are centered on understanding and reducing cell and stack performance degradation to an acceptable level to advance the technology readiness level of HTSE and to justify further large-scale demonstration activities. This report provides a summary of our FY10 experimental program, which has been focused on advanced cell and stack development and degradation studies. Advanced cell and stack development activities are under way at five technology partners: MSRI, Versa Power, Ceramatec, NASA Glenn, and St. Gobain. Performance evaluation of the advanced technology cells and stacks has been performed by the technology partners, by MIT and the University of Connecticut and at the INL HTE Laboratory. Summaries of these development activities and test results are presented.
Exponential Time Decay Estimates for the Landau Equation on Torus
Wu, Kung-Chien
2013-01-01
We study the time decay estimates for the linearized Landau equation on torus when the initial perturbation is not necessarily smooth. Our result reveals the kinetic and fluid aspects of the equation. We design a Picard-type iteration and Mixture lemma for constructing the increasingly regular kinetic like waves, they are carried by transport equations and have exponential time decay rate. The fluid like waves are constructed as part of the long-wave expansion in the spectrum of the Fourier m...
Synchronization and balancing on the N-torus
Scardovi, Luca; Sarlette, Alain; Sepulchre, Rodolphe
2007-01-01
In this paper. we study the behavior of a network of N agents, each evolving on the circle. We propose a novel algorithm that achieves synchronization or balancing in phase models under mild connectedness assumptions on the (possibly time-varying and unidirectional) communication graphs. The global convergence analysis on the N-torus is a distinctive feature of the present work with respect to previous results that have focused on convergence in the Euclidean space. Peer reviewed
Pressure Safety: Advanced Self-Study 30120
Energy Technology Data Exchange (ETDEWEB)
Glass, George [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2016-02-29
Pressure Safety Advance Self-Study (Course 30120) consists of an introduction, five modules, and a quiz. To receive credit in UTrain for completing this course, you must score 80% or better on the 15-question quiz (check UTrain). Directions for initiating the quiz are appended to the end of this training manual. This course contains several links to LANL websites. UTrain might not support active links, so please copy links into the address line in your browser.
A study of factors influencing advanced puberty
Yong Jun Park; Chang Min Moon; Hwang Jae Yoo
2010-01-01
Purpose : The purpose of this study was to evaluate the timing of puberty and the factors inducing advanced puberty in elemental school students of low grades. Methods : The 1st, 2nd, and 3rd grade elemental students from the Goyang province were randomly selected, and their sexual maturation rate was assessed by physical examination. After obtaining an informed consent, a questionnaire was administered to the parents; eating habits, lifestyle, use of growth-inducing medication, and prese...
Initial Diagnostics for the National Spherical Torus Experiment
International Nuclear Information System (INIS)
The spherical torus (ST) approach to magnetic confinement has many attractive features as both a fusion reactor concept and a volume neutron source. The National Spherical Torus Experiment (NSTX) is under construction at the Princeton Plasma Physics Laboratory (PPPL), and it is designed to achieve plasma parameters needed for a proof-of-principle test of the ST concept. Discharges with magnetic fields of 2.3 kG on axis and plasma currents of 1 MA will be heated with 6 MW of radio frequency (RF) power and 5 MW of neutral beams, and pulse lengths up to 5 seconds are planned. Central electron temperatures of about 4 keV are expected with RF heating, and theoretical studies show that high values of b and bn can be achieved
A Comprehensive Analysis of Io's Atmosphere and Torus
Schneider, Nicholas M.
1999-01-01
This final report describes the results of our NASA/Planetary Atmospheres program studying the atmosphere of Jupiter's moon Io and the plasma torus which it creates. Io is the most volcanically active body in the solar system, and it is embedded deep within the strongest magnetosphere of any planet. This combination of circumstances leads to a host of scientifically compelling phenomena, including (1) an atmosphere out of proportion with such a small object, (2) a correspondingly large atmospheric escape rate, (3) a ring of dense plasma locked in a feedback loop with the atmosphere, and (4) a host of Io-induced emissions from radio bursts to UV auroral spots on Jupiter. This proposal seeks to continue our investigation into the physics connecting these phenomena, with emphasis on Io's atmosphere and plasma torus. The physical processes are clearly of interest for Io, and also other places in the solar system where they are important but not so readily observable.
General quantization of canonical maps on a two-torus
International Nuclear Information System (INIS)
Canonical maps on a two-torus in phase space are quantized under most general conditions. Recent results by Keating et al (1999 Nonlinearity 12 579) are thus fully extended in two directions: (a) The translational component of a general canonical map is included in the quantization. (b) All values of Planck's constant, consistent with the toral boundary conditions (BCs), are considered; generically, these values are rational numbers whose numerator must satisfy a number-theoretical condition. Besides the condition on Planck's constant, the quantization is possible only for particular, 'allowed' BCs on the torus. The general equation determining these BCs is derived. Allowed BCs may not exist in some cases; representative examples are the irrational skew translations and Kronecker maps. Exact versions of Egorov's theorem are shown to hold under some conditions. Composition and representation properties of the quantization scheme are studied. (author)
Short interval expansion of R\\'enyi entropy on torus
Chen, Bin; Zhang, Jia-ju
2016-01-01
We investigate the short interval expansion of the R\\'enyi entropy for two-dimensional conformal field theory (CFT) on a torus. We require the length of the interval $\\ell$ to be small with respect to the spatial and temporal sizes of the torus. The operator product expansion of the twist operators allows us to compute the short interval expansion of the R\\'enyi entropy at any temperature. In particular, we pay special attention to the large $c$ CFTs dual to the AdS$_3$ gravity and its cousins. At both low and high temperature limits, we read the R\\'enyi entropies to order $\\ell^6$, and find good agreements with holographic results. Moreover, the expansion allows us to read $1/c$ contribution, which is hard to get by expanding the thermal density matrix. We generalize the study to the case with the chemical potential as well.
Center for Advanced Energy Studies Program Plan
Energy Technology Data Exchange (ETDEWEB)
Kevin Kostelnik
2005-09-01
The world is facing critical energy-related challenges regarding world and national energy demands, advanced science and energy technology delivery, nuclear engineering educational shortfalls, and adequately trained technical staff. Resolution of these issues is important for the United States to ensure a secure and affordable energy supply, which is essential for maintaining U.S. national security, continued economic prosperity, and future sustainable development. One way that the U.S. Department of Energy (DOE) is addressing these challenges is by tasking the Battelle Energy Alliance, LLC (BEA) with developing the Center for Advanced Energy Studies (CAES) at the Idaho National Laboratory (INL). By 2015, CAES will be a self-sustaining, world-class, academic and research institution where the INL; DOE; Idaho, regional, and other national universities; and the international community will cooperate to conduct critical energy-related research, classroom instruction, technical training, policy conceptualization, public dialogue, and other events.
Braiding surface links which are coverings over the standard torus
NAKAMURA, Inasa
2009-01-01
We consider a surface link in the 4-space which can be presented by a simple branched covering over the standard torus, which we call a torus-covering link. Torus-covering links include spun $T^2$-knots and turned spun $T^2$-knots. In this paper we braid a torus-covering link over the standard 2-sphere. This gives an upper estimate of the braid index of a torus-covering link. In particular we show that the turned spun $T^2$-knot of the torus $(2,\\,p)$-knot has the braid index four.
ITER - torus vacuum pumping system remote handling issues
International Nuclear Information System (INIS)
This report describes further design issues concerning remote maintenance of torus vacuum pumping systems options for ITER. The key issues under investigation in this report are flask support systems for valve seal exchange operations for the compound cryopump scheme and remote maintenance of a proposed multiple turbomolecular pump (TMP) system, an alternative ITER torus exhaust pumping option. Previous studies have shown that the overhead support methods for seal exchange flask equipment could malfunction due to valve/flask misalignment. A floor-mounted support system is described in this report. This scheme provides a more rigid support system for seal exchange operations. An alternative torus pumping system, based on the use of multiple TMPs, is studied from a remote maintenance standpoint. In this concept, centre distance spacing for pump/valve assemblies is too restrictive for remote maintenance. Recommendations are made for adequate spacing of these assemblies based on commercially-available 0.8 m and 1.0 m diameter valves. Fewer pumps will fit in this arrangement, which implies a need for larger TMPs. Pumps of this size are not commercially available. Other concerns regarding the servicing and storage of remote handling equipment in cells are also identified. (9 figs.)
A study of factors influencing advanced puberty
Directory of Open Access Journals (Sweden)
Yong Jun Park
2010-02-01
Full Text Available Purpose : The purpose of this study was to evaluate the timing of puberty and the factors inducing advanced puberty in elemental school students of low grades. Methods : The 1st, 2nd, and 3rd grade elemental students from the Goyang province were randomly selected, and their sexual maturation rate was assessed by physical examination. After obtaining an informed consent, a questionnaire was administered to the parents; eating habits, lifestyle, use of growth-inducing medication, and present illness of the students were evaluated to determine the factors that induced advanced puberty. The data were statistically analyzed. Results : We selected 170 children and the girls:boys sex ratio was 1.2:1. Two 9-year-old boys were in genital stage 2. Two (14.3% 6-year-old girls, 6 (19.4% 7-year-old girls, 15 (39.6% 8-year-old girls, and 4 (57.1% 9-year-old girls were in breast stage 2. The average pubertal timing predicted for girls was 9.11¡?#?.86; years. The main factors influencing pubertal timing were obesity scale, frequency of eating fast food, and the use of growth-inducing medication. A high rating on the obesity scale and high frequency of eating fast food indicated advanced stage of puberty. Growth-inducing medication induced puberty through obesity. Conclusion : We proposed that predictive average pubertal timing in girls was 9.11¡?#?.86; years, which was consistent with the previously reported findings from abroad. The significant influencing factors in advanced puberty were obesity scale and frequency of fast food.
Directory of Open Access Journals (Sweden)
AlZarea BK
2016-02-01
Full Text Available Bader K AlZarea Department of Prosthodontics, College of Dentistry, Al Jouf University, Al Jouf, Kingdom of Saudi Arabia Background: The most remarkable exostoses of the human jaws are torus palatinus (TP and torus mandibularis (TM. The aim of the present study was to actuate the prevalence of TP and TM in relation to age and sex among the edentulous patients of Saudi Arabia. Methods: The present study included 847 edentulous subjects (458 men and 389 women aged between 51 and 79 years. The subjects were examined for the existence of tori by clinical inspection and palpation. Statistical analysis was performed using SPSS for Windows version. Results: Among the 847 subjects, 149 (17.59% had either TP or TM. Sixty six (7.79% subjects had TP, whereas 83 (9.80% had TM. The maximum percentage (36.36% of tori was observed in the age-group of 60–69 years. The percentage of males with either tori was higher (19.0% when compared to females (15.94%. According to shape, the occurrence of flat-shaped TP (57.58% and bilateral solitary TM (39.76% was more common. Conclusion: No significant difference in the presence of tori with respect to sex and age was observed. A comparatively increased prevalence of TP and TM was however observed, and this should be taken into consideration while planning for prosthodontic and periodontal therapy in these patients. Keywords: edentulous, prevalence, torus mandibularis, torus palatinus
International Nuclear Information System (INIS)
A spherical torus (ST) fusion energy development path which is complementary to the proposed tokamak burning plasma experiments such as ITER is described. The ST strategy focuses on a compact component test facility (CTF) and high performance advanced regimes leading to more attractive Demo and power plant scale reactors. To provide the physical basis for the CTF an intermediate step needs to be taken, which we refer to as the 'next-step spherical torus' (NSST) device and which we examine in some detail herein. NSST is a 'performance extension' stage ST with a plasma current of 5-10 MA, R = 1.5m, BT ≤ 2.6 T and the possibility of varying physical parameters. The mission of NSST is to (1) provide a sufficient physical basis for the design of a CTF; (2) explore advanced operating scenarios with high bootstrap current fraction and high performance which can be utilized by CTF, Demo, and power plants; and (3) contribute to the general science of high β toroidal plasmas. The NSST is designed to utilize a TFTR-like site to minimize the cost and time required for design and construction. (author)
Recent advance in study on FAC
International Nuclear Information System (INIS)
Flow accelerated corrosion (FAC) is an important issue for aging fossil and nuclear power plants. FAC causes thinning of pipe walls which occasionally leads to a piping rupture accident. 'Research Committee on Improvement and Practical Use of Pipe-Wall-Thinning Management' of JSME revised technical knowledge regarding pipe wall thinning phenomena attached to JSME 'Code for Power Generation Facilities - Rule on Pipe Wall Thinning Management-JSME-S CA1 2005.' This paper summarizes the technical knowledge of recent advances in study on FAC. (author)
Advanced SFR concept design studies at KAERI
International Nuclear Information System (INIS)
Full text: Advanced SFR design concepts have been proposed and evaluated against the design requirements to satisfy the Gen IV technology goals. Two types of conceptual core designs, Breakeven and TRU burner cores were developed. Breakeven core is 1,200 MWe and does not have blankets to enhance the proliferation resistance. According to the current study, TRU burning rate increases linearly with the rated core powers from 600 MWe to 1,200 MWe. Considering 1) the realistic size of an SFR demonstration reactor for the long-term R and D plan with the goal of a demonstration SFR construction by 2028, and 2) the availability of a KALIMER-600 reactor system design that was developed in the last R and D phase, a TRU burner of 600 MWe was selected. The heat transport system of Advanced SFR was designed to be a pool type to enhance system safety through slow system transients, where primary sodium is contained in a reactor vessel. The heat transport system is composed of Primary Heat Transport System (PHTS), Intermediate Heat Transport System (IHTS), Steam Generating System (SGS) and Residual Heat Removal System (RHRS). The heat transport system was established through trade studies in order to enhance the safety and to improve the economics and performance of the KALIMER-600 design. Trade studies were performed for the number of IHTS loops, the number of PHTS pumps, Steam Generator (SG) design concepts, energy conversion system concepts, cover gas operation methods, and an improved concept of safety-graded passive decay heat removal system. From the study, the heat transport system of Advanced SFR has design features such as two IHTS loops, a Rankine cycle energy conversion system, two double-wall straight tube type SGs, and a passive decay heat removal system. In order to secure the economic competitiveness of an SFR, several concepts were implemented in the mechanical structural design without losing the reactor safety level. The material of reactor vessel and internal
Technological advances for studying human behavior
Roske-Hofstrand, Renate J.
1990-01-01
Technological advances for studying human behavior are noted in viewgraph form. It is asserted that performance-aiding systems are proliferating without a fundamental understanding of how they would interact with the humans who must control them. Two views of automation research, the hardware view and the human-centered view, are listed. Other viewgraphs give information on vital elements for human-centered research, a continuum of the research process, available technologies, new technologies for persistent problems, a sample research infrastructure, the need for metrics, and examples of data-link technology.
A comparative study of various advanced fusions
International Nuclear Information System (INIS)
For the purpose of comparing the merits and demerits of various advanced fuel cycles, parametric studies of operation conditions are examined. The effects of nuclear elastic collisions and synchrotron radiation are taken into account. It is found that the high-#betta# Catalyzed DD fuel cycle with the transmutation of fusion-produced tritium into helium-3 is most feasible from the point of view of neutron production and tritium handling. The D-D fuel cycles seem to be less attractive compared to the Catalyzed DD. The p-11B and p-6Li fusion plasmas hardly attain the plasma Q value relevant to reactors. (author)
Foliations with unbounded deviation on the two-dimensional torus
Panov, Dmitri
2002-01-01
There exists a smooth foliation with 3 singular points on the two-dimensional torus such that any lifting of a leaf of this foliation on the universal covering of the torus is a dense subset of the covering.
Mirror Advanced Reactor Study interim design report
International Nuclear Information System (INIS)
The status of the design of a tenth-of-a-kind commercial tandem-mirror fusion reactor is described at the midpoint of a two-year study. When completed, the design is to serve as a strategic goal for the mirror fusion program. The main objectives of the Mirror Advanced Reactor Study (MARS) are: (1) to design an attractive tandem-mirror fusion reactor producing electricity and synfuels (in alternate versions), (2) to identify key development and technology needs, and (3) to exploit the potential of fusion for safety, low activation, and simple disposal of radioactive waste. In the first year we have emphasized physics and engineering of the central cell and physics of the end cell. Design optimization and trade studies are continuing, and we expect additional modifications in the end cells to further improve the performance of the final design
Mirror Advanced Reactor Study interim design report
Energy Technology Data Exchange (ETDEWEB)
1983-04-01
The status of the design of a tenth-of-a-kind commercial tandem-mirror fusion reactor is described at the midpoint of a two-year study. When completed, the design is to serve as a strategic goal for the mirror fusion program. The main objectives of the Mirror Advanced Reactor Study (MARS) are: (1) to design an attractive tandem-mirror fusion reactor producing electricity and synfuels (in alternate versions), (2) to identify key development and technology needs, and (3) to exploit the potential of fusion for safety, low activation, and simple disposal of radioactive waste. In the first year we have emphasized physics and engineering of the central cell and physics of the end cell. Design optimization and trade studies are continuing, and we expect additional modifications in the end cells to further improve the performance of the final design.
Slicing the Torus: Obscuring Structures in Quasars
Elvis, Martin
2012-07-01
Quasars and Active Galactic Nuclei (AGNs) are often obscured by dust and gas. It is normally assumed that the obscuration occurs in an oblate "obscuring torus", that begins at the radius at which the most refractive dust can remain solid. The most famous form of this torus is a donut-shaped region of molecular gas with a large scale-height. While this model is elegant and accounts for many phenomena at once, it does not hold up to detailed tests. Instead the obscuration in AGNs must occur on a wide range of scales and be due to a minimum of three physically distinct absorbers. Slicing the "torus" into these three regions will allow interesting physics of the AGN to be extracted.
Slicing the Torus: Obscuring Structures in Quasars
International Nuclear Information System (INIS)
Quasars and Active Galactic Nuclei (AGNs) are often obscured by dust and gas. It is normally assumed that the obscuration occurs in an oblate 'obscuring torus', that begins at the radius at which the most refractive dust can remain solid. The most famous form of this torus is a donut-shaped region of molecular gas with a large scale-height. While this model is elegant and accounts for many phenomena at once, it does not hold up to detailed tests. Instead the obscuration in AGNs must occur on a wide range of scales and be due to a minimum of three physically distinct absorbers. Slicing the 'torus' into these three regions will allow interesting physics of the AGN to be extracted.
Slicing the Torus: Obscuring Structures in Quasars
Elvis, Martin
2012-01-01
Quasars and Active Galactic Nuclei (AGNs) are often obscured by dust and gas. It is normally assumed that the obscuration occurs in an oblate "obscuring torus", that begins at the radius at which the most refractive dust can remain solid. The most famous form of this torus is a donut-shaped region of molecular gas with a large scale-height. While this model is elegant and accounts for many phenomena at once, it does not hold up to detailed tests. Instead the obscuration in AGNs must occur on a wide range of scales and be due to a minimum of three physically distinct absorbers. Slicing the "torus" into these three regions will allow interesting physics of the AGN to be extracted.
Directory of Open Access Journals (Sweden)
Masahiro Nakamura
2012-01-01
Full Text Available In this paper, we consider the following sliding puzzle called torus puzzle. In an m by n board, there are mn pieces numbered from 1 to mn. Initially, the pieces are placed in ascending order. Then they are scrambled by rotating the rows and columns without the player’s knowledge. The objective of the torus puzzle is to rearrange the pieces in ascending order by rotating the rows and columns. We provide a solution to this puzzle. In addition, we provide lower and upper bounds on the number of steps for solving the puzzle. Moreover, we consider a variant of the torus puzzle in which each piece is colored either black or white, and we present a hardness result for solving it.
Non-minimal bridge positions of torus knots are stabilized
Ozawa, Makoto
2010-01-01
We show that any non-minimal bridge decomposition of a torus knot is stabilized and that $n$-bridge decompositions of a torus knot are unique for any integer $n$. This implies that a knot in a bridge position is a torus knot if and only if there exists a torus containing the knot such that it intersects the bridge sphere in two essential loops.
NATO Advanced Study Institute on Metal Hydrides
1981-01-01
In the last five years, the study of metal hydrides has ex panded enormously due to the potential technological importance of this class of materials in hydrogen based energy conversion schemes. The scope of this activity has been worldwide among the industrially advanced nations. There has been a consensus among researchers in both fundamental and applied areas that a more basic understanding of the properties of metal/hydrogen syster;,s is required in order to provide a rational basis for the selection of materials for specific applications. The current worldwide need for and interest in research in metal hydrides indicated the timeliness of an Advanced Study Insti tute to provide an in-depth view of the field for those active in its various aspects. The inclusion of speakers from non-NATO coun tries provided the opportunity for cross-fertilization of ideas for future research. While the emphasis of the Institute was on basic properties, there was a conscious effort to stimulate interest in the applic...
Energy Technology Data Exchange (ETDEWEB)
J.A. Breslau; S.C. Jardin; W. Park
2003-01-21
Injection of lower-hybrid current drive into the current ramp-up phase of the Joint European Torus (JET) plasma discharges has been observed to produce an annular current distribution with a core region of essentially zero current density [Hawkes, et al., Phys. Rev. Lett. 87 (2001) 115001]. Similar ''current holes'' have been observed in the Japan Atomic Energy Research Institute (JAERI) Tokamak 60 Upgrade (JT-60U) plasma discharges with off-axis current drive supplied by the bootstrap current [T. Fujita, et al., Phys. Rev. Lett. 87 (2001) 245001]. In both cases, the central current does not go negative although current diffusion calculations indicate that there is sufficient noninductive current drive for this to occur. This is explained by the Multi-level 3-D code (M3D) nonlinear 2-D and 3-D resistive magnetohydrodynamic (MHD) simulations in toroidal geometry, which predict that these plasma discharges undergo n = 0 reconnection events--''axisymmetric sawteeth''--that redistribute th e current to hold its core density near zero. Unlike conventional sawteeth, these events retain the symmetry of the equilibrium, and thus are best viewed as a transient loss of equilibrium caused when an iota = 0 rational surface enters the plasma. If the current-density profile has a central minimum, this surface will enter on axis; otherwise it will enter off-axis. In the first case, the reconnection is limited to a small region around the axis and clamps the core current at zero. In the second case, more typical of the JET experiments, the core current takes on a finite negative value before the iota = 0 surface appears, resulting in discrete periodic axisymmetric sawtooth events with a finite minor radius. Interpretation of the simulation results is given in terms of analytic equilibrium theory, and the relation to conventional sawteeth and to a recent reduced-MHD analysis of this phenomenon in cylindrical geometry [Huysmans, et al., Phys
Tightening elastic (n, 2)-torus knots
International Nuclear Information System (INIS)
We present a theory for equilibria of elastic torus knots made of a single thin, uniform, homogeneous, isotropic, inextensible, unshearable rod of circular cross-section. The theory is formulated as a special case of an elastic theory of geometrically exact braids consisting of two rods winding around each other while remaining at constant distance. We introduce braid strains in terms of which we formulate a second-order variational problem for an action functional that is the sum of the rod elastic energies and constraint terms related to the inextensibility of the rods. The Euler-Lagrange equations for this problem, partly in Euler-Poincare form, yield a compact system of ODEs suitable for numerical solution. By solving an appropriate boundary- value problem for these equations we study knot equilibria as the dimensionless ropelength parameter is varied. We are particularly interested in the approach of the purely geometrical ideal (tightest) limit. For the trefoil knot the tightest shape we could get has a ropelength of 32.85560666, which is remarkably close to the best current estimate. For the pentafoil we find a symmetry-breaking bifurcation
On Liftings of Local Torus Actions to Fiber Bundles
Yoshida, Takahiko
2007-01-01
In this note we define a lifting of a local torus action modeled on the standard representation (we call it a local torus action for simplicity) to a principal torus bundle, and show that there is an obstruction class for the existence of liftings in the first cohomology of the fundamental group of the orbit space with coefficients in a certain module.
Manuel Ramon Osorio Castillo; Hernando Alberto Alvarado Marquez; Antonio Díaz Caballero
2014-01-01
ResumenLos huesos maxilares no son ajenos a las patologías que se pueden presentar en el sistema esquelético. Algunas de esas condiciones y patologías son singulares por sus características clínicas, su distribución y prevalencia. Los torus palatinos, los torus mandibulares (TM) y las exostosis de los maxilares son un claro ejemplo de ellos. Hasta la presente existen ideas especulativas acerca de su etiopatogenia, de los factores asociados, de su incidencia y prevalencia, de su necesidad de t...
Diffusion on the torus for Hamiltonian maps
International Nuclear Information System (INIS)
For a mapping of the torus T2 the authors propose a definition of the diffusion coefficient D suggested by the solution of the diffusion equation on T2. The definition of D, based on the limit of moments of the invariant measure, depends on the set Ω where an initial uniform distribution is assigned. For the algebraic automorphism of the torus the limit is proved to exist and to have the same value for almost all initial sets Ω in the subfamily of parallelograms. Numerical results show that it has the same value for arbitrary polygons Ω and for arbitrary moments. 13 refs., 3 figs
Oliversen, Ronald J.; Scherb, Frank; Roesler, Fred L.
1991-01-01
Io torus spectrometry obtained in the S II and S III forbidden lines during February-March 1981 indicate that these emissions are correlated in the warm torus, and possess similar scale heights along the magnetic field lines. The observed emission scale heights can be used to estimate the ion temperature parallel to the magnetic field, given the effective ion mass. Attention is also given to simultaneous measurements of the S II forbidden 6731 line profile obtained on one night with a Fabry-Perot scanning spectrophotometer.
NATO Advanced Study Institute on Superconducting Electronics
Nisenhoff, Martin; Superconducting Electronics
1989-01-01
The genesis of the NATO Advanced Study Institute (ASI) upon which this volume is based, occurred during the summer of 1986 when we came to the realization that there had been significant progress during the early 1980's in the field of superconducting electronics and in applications of this technology. Despite this progress, there was a perception among many engineers and scientists that, with the possible exception of a limited number of esoteric fundamental studies and applications (e.g., the Josephson voltage standard or the SQUID magnetometer), there was no significant future for electronic systems incorporating superconducting elements. One of the major reasons for this perception was the aversion to handling liquid helium or including a closed-cycle helium liquefier. In addition, many critics felt that IBM's cancellation of its superconducting computer project in 1983 was "proof" that superconductors could not possibly compete with semiconductors in high-speed signal processing. From our persp...
Directory of Open Access Journals (Sweden)
Manuel Ramon Osorio Castillo
2014-06-01
Full Text Available ResumenLos huesos maxilares no son ajenos a las patologías que se pueden presentar en el sistema esquelético. Algunas de esas condiciones y patologías son singulares por sus características clínicas, su distribución y prevalencia. Los torus palatinos, los torus mandibulares (TM y las exostosis de los maxilares son un claro ejemplo de ellos. Hasta la presente existen ideas especulativas acerca de su etiopatogenia, de los factores asociados, de su incidencia y prevalencia, de su necesidad de tratamiento, lo que puede crear confusión entre los clínicos tanto en diagnóstico como en el manejo.El torus como tumor óseo benigno puede localizarse en el maxilar a nivel del paladar, o en la mandíbula a nivel de las tablas internas; o puede aparecer en cualquier parte del esqueleto. El TM es una exostosis o crecimiento óseo en la superficie lingual de la mandíbula. Este crecimiento ocurre generalmente cerca de la línea milohioidea, opuesto a los premolares, pero se puede extender del canino al primer molar. La mucosa que los recubre tiende a ser fina y no tolera por lo general las fuerzas de las prótesis que se colocan encima de ellos. La incidencia del torus de la mandíbula es baja en el 6% a 12.5% entre caucásicos y en los habitantes de la llanura africana. De manera contraria, algunos autores reportan una prevalencia mucho más elevada en la Costa Atlántica Colombiana.Se presenta el caso de un paciente con torus mandibulares bilaterales, con muchos años de crecimiento, hasta que por situaciones tanto fonéticas como de ulceraciones repetitivas decidió someterse al acto quirúrgico de forma bilateral. Se presentan algunas consideraciones para el manejo de esta. (Duazary 2008; 111-114AbstractThe jawbone is not a strange to the pathologies that can occur in the skeletal system. Some of these terms and conditions are unique for their clinical features, distribution and prevalence. The torus palate, jawbone torus (TM in spanish and
Classification Studies in an Advanced Air Classifier
Routray, Sunita; Bhima Rao, R.
2016-01-01
In the present paper, experiments are carried out using VSK separator which is an advanced air classifier to recover heavy minerals from beach sand. In classification experiments the cage wheel speed and the feed rate are set and the material is fed to the air cyclone and split into fine and coarse particles which are collected in separate bags. The size distribution of each fraction was measured by sieve analysis. A model is developed to predict the performance of the air classifier. The objective of the present model is to predict the grade efficiency curve for a given set of operating parameters such as cage wheel speed and feed rate. The overall experimental data with all variables studied in this investigation is fitted to several models. It is found that the present model is fitting good to the logistic model.
The Pan American Advanced Studies Institute
Arous, Gérard; Ferrari, Pablo; Newman, Charles; Sidoravicius, Vladas; Vares, Maria
2014-01-01
This volume features selected and peer-reviewed articles from the Pan-American Advanced Studies Institute (PASI). The chapters are written by international specialists who participated in the conference. Topics include developments based on breakthroughs in the mathematical understanding of phenomena describing systems in highly inhomogeneous and disordered media, including the KPZ universality class (describing the evolution of interfaces in two dimensions), spin glasses, random walks in random environment, and percolative systems. PASI fosters a collaboration between North American and Latin American researchers and students. The conference that inspired this volume took place in January 2012 in both Santiago de Chile and Buenos Aires. Researchers and graduate students will find timely research in probability theory, statistical physics and related disciplines.
Control definition study for advanced vehicles
Lapins, M.; Martorella, R. P.; Klein, R. W.; Meyer, R. C.; Sturm, M. J.
1983-01-01
The low speed, high angle of attack flight mechanics of an advanced, canard-configured, supersonic tactical aircraft designed with moderate longitudinal relaxed static stability (Static Margin, SM = 16% C sub W at M = 0.4) was investigated. Control laws were developed for the longitudinal axis (""G'' or maneuver and angle of attack command systems) and for the lateral/directional axes. The performance of these control laws was examined in engineering simulation. A canard deflection/rate requirement study was performed as part of the ""G'' command law evaluation at low angles of attack. Simulated coupled maneuvers revealed the need for command limiters in all three aircraft axes to prevent departure from controlled flight. When modified with command/maneuver limiters, the control laws were shown to be adequate to prevent aircraft departure during aggressive air combat maneuvering.
Advanced Manned Launch System (AMLS) study
Ehrlich, Carl F., Jr.; Potts, Jack; Brown, Jerry; Schell, Ken; Manley, Mary; Chen, Irving; Earhart, Richard; Urrutia, Chuck; Randolph, Ray; Morris, Jim
1992-01-01
To assure national leadership in space operations and exploration in the future, NASA must be able to provide cost effective and operationally efficient space transportation. Several NASA studies and the joint NASA/DoD Space Transportation Architecture Studies (STAS) have shown the need for a multi-vehicle space transportation system with designs driven by enhanced operations and low costs. NASA is currently studying an advanced manned launch system (AMLS) approach to transport crew and cargo to the Space Station Freedom. Several single and multiple stage systems from air-breathing to all-rocket concepts are being examined in a series of studies potential replacements for the Space Shuttle launch system in the 2000-2010 time frame. Rockwell International Corporation, under contract to the NASA Langley Research Center, has analyzed a two-stage all-rocket concept to determine whether this class of vehicles is appropriate for the AMLS function. The results of the pre-phase A study are discussed.
Observation of mass loading in the Io plasma torus
Brown, Michael E.
1994-01-01
Ground-based high-resolution spectra of emission from the Io plasma torus obtained during 53 nights of observation over a seven month period are used to measure the torus rotation speed and discern regions of the torus that are slowed by mass loading of newly ionized materials. The amount of torus slowing implies that between 2000 and 3000 kg/sec are being ionized by the torus. The slowing is spread azimuthally throughout the orbit of Io, suggesting that neutral materials emanating from Io are distributed around Jupiter much more uniformly than currently believed.
Advanced hybrid vehicle propulsion system study
Schwarz, R.
1982-01-01
Results are presented of a study of an advanced heat engine/electric automotive hybrid propulsion system. The system uses a rotary stratified charge engine and ac motor/controller in a parallel hybrid configuration. The three tasks of the study were (1) parametric studies involving five different vehicle types, (2) design trade-off studies to determine the influence of various vehicle and propulsion system paramaters on system performance fuel economy and cost, and (3) a conceptual design establishing feasibility at the selected approach. Energy consumption for the selected system was .034 1/km (61.3 mpg) for the heat engine and .221 kWh/km (.356 kWh/mi) for the electric power system over a modified J227 a schedule D driving cycle. Life cycle costs were 7.13 cents/km (11.5 cents/mi) at $2/gal gasoline and 7 cents/kWh electricity for 160,000 km (100,000 mi) life.
Berman, D S
1998-01-01
The D-3 brane is examined from the point of view of the wrapped M-theory five brane on a torus. In particular, the S-dual versions of the 3-brane are identified as coming from different gauge choices of the auxiliary field that is introduced in the PST description of the five brane world volume theory.
Magnetostatics of the uniformly polarized torus
DEFF Research Database (Denmark)
Beleggia, Marco; De Graef, Marc; Millev, Yonko
2009-01-01
We provide an exhaustive description of the magnetostatics of the uniformly polarized torus and its derivative self-intersecting (spindle) shapes. In the process, two complementary approaches have been implemented, position-space analysis of the Laplace equation with inhomogeneous boundary...
Bridge spectra of iterated torus knots
Zupan, Alexander
2013-01-01
We determine the set of all genus g bridge numbers of many iterated torus knots, listing these numbers in a sequence called the bridge spectrum. In addition, we prove a structural lemma about the decomposition of a strongly irreducible bridge surface induced by cutting along a collection of essential surfaces.
A principle for ideal torus knots
DEFF Research Database (Denmark)
Olsen, Kasper Wibeck; Bohr, Jakob
2013-01-01
Using bent-helix embeddings, we investigate simple and knotted torus windings that are made of tubes of finite thickness. Knots which have the shortest rope length are often denoted as ideal structures. Conventionally, the ideal structures are found by rope shortening routines. It is shown that a...
Spherical torus, compact fusion at low field
International Nuclear Information System (INIS)
A spherical torus is obtained by retaining only the indispensable components on the inboard side of a tokamak plasma, such as a cooled, normal conductor that carries current to produce a toroidal magnetic field. The resulting device features an exceptionally small aspect ratio (ranging from below 2 to about 1.3), a naturally elongated D-shaped plasma cross section, and ramp-up of the plasma current primarily by noninductive means. As a result of the favorable dependence of the tokamak plasma behavior to decreasing aspect ratio, a spherical torus is projected to have small size, high beta, and modest field. Assumption Mirnov confinement scaling, an ignition spherical torus at a field of 2 T features a major radius of 1.5 m, a minor radius of 1.0 m, a plasma current of 14 MA, comparable toroidal and poloidal field coil currents, an average beta of 24%, and a fusion power of 50 MW. At 2 T, a Q = 1 spherical torus will have a major radius of 0.8 m, a minor radius of 0.5 m, and a fusion power of a few megawatts
Torus-like Dielectric D2-brane
Hyakutake, Yoshifumi
2001-01-01
We find new solutions corresponding to torus-like generalization of dielectric D2-brane from the viewpoint of D2-brane action and N D0-branes one. These are meta-stable and would decay to the spherical dielectric D2-brane.
Electrostatic confinement in a bumpy torus
International Nuclear Information System (INIS)
In a closed-field-line device such as a bumpy torus, the combined E x B and del B drifts lead to charge separation that is balanced by the ion polarization drift. In this work, we determine self-consistent potential and density profiles and the condition for electric island formation
Monotone periodic orbits for torus homeomorphisms
Parwani, Kamlesh
2005-01-01
Let f be a homeomorphism of the torus isotopic to the identity and suppose that there exists a periodic orbit with a non-zero rotation vector (p/q,r/q), then f has a topologically monotone periodic orbit with the same rotation vector.
Advances in soil-structure interaction studies
International Nuclear Information System (INIS)
It is utmost important that lifeline infrastructures (such as bridges, hospitals, power plants, dams etc.) are safe and functional during earthquakes as damage or collapse of these structures may have far reaching implications. A lifeline's failure may hamper relief and rescue operations required just after an earthquake and secondly its indirect economical losses may be very severe. Therefore, safety of these structures during earthquakes is vital. Further, damage to nuclear facilities during earthquake may lead to disaster. These structures should be designed adequately taking into account all the important issues. Soil-Structure Interaction (SSI) is one of the design issues, which is often overlooked and even in some cases ignored. The effects of dynamic SSI are well understood and practiced in the nuclear power industry (for large foundations of the nuclear containment structures) since sixties. However, in last decade, there are many advances in techniques of SSI and those need to be incorporated in practice. Failures of many structures occurred during the 1989 Loma Prieta and 1994 Northridge, California earthquakes and the 1995 Kobe, Japan earthquake due to SSI or a related issue. Many jetties had failed in Andaman and Nicobar islands due to Sumatra earthquake and ensuing tsunamis. It is because of this recent experience that the importance of SSI on dynamic response of structures during earthquakes has been fully realized. General belief that the SSI effects are always beneficial for the structure is not correct. Some cases have been presented where it is shown that SSI effects are detrimental for the stability of the structure. This paper addresses the effects of dynamic SSI on the response of the structures and explains its importance. Further advances in SSI studies have been discussed
Conceptual study of advanced PWR core design
International Nuclear Information System (INIS)
The purpose of this project is for developing and verifying the core design concepts with enhanced safety and economy, and associated methodologies for core analyses. From the study of the sate-of-art of foreign advanced reactor cores, we developed core concepts such as soluble boron free, high convertible and enhanced safety core loaded semi-tight lattice hexagonal fuel assemblies. To analyze this hexagonal core, we have developed and verified some neutronic and T/H analysis methodologies. HELIOS code was adopted as the assembly code and HEXFEM code was developed for hexagonal core analysis. Based on experimental data in hexagonal lattices and the COBRA-IV-I code, we developed a thermal-hydraulic analysis code for hexagonal lattices. Using the core analysis code systems developed in this project, we designed a 600 MWe core and studied the feasibility of the core concepts. Two additional scopes were performed in this project : study on the operational strategies of soluble boron free core and conceptual design of large scale passive core. By using the axial BP zoning concept and suitable design of control rods, this project showed that it was possible to design a soluble boron free core in 600 MWe PWR. The results of large scale core design showed that passive concepts and daily load follow operation could be practiced. (author). 15 refs., 52 tabs., 101 figs
Conceptual study of advanced PWR core design
Energy Technology Data Exchange (ETDEWEB)
Kim, Young Jin; Chang, Moon Hee; Kim, Keung Ku; Joo, Hyung Kuk; Kim, Young Il; Noh, Jae Man; Hwang, Dae Hyun; Kim, Taek Kyum; Yoo, Yon Jong
1997-09-01
The purpose of this project is for developing and verifying the core design concepts with enhanced safety and economy, and associated methodologies for core analyses. From the study of the sate-of-art of foreign advanced reactor cores, we developed core concepts such as soluble boron free, high convertible and enhanced safety core loaded semi-tight lattice hexagonal fuel assemblies. To analyze this hexagonal core, we have developed and verified some neutronic and T/H analysis methodologies. HELIOS code was adopted as the assembly code and HEXFEM code was developed for hexagonal core analysis. Based on experimental data in hexagonal lattices and the COBRA-IV-I code, we developed a thermal-hydraulic analysis code for hexagonal lattices. Using the core analysis code systems developed in this project, we designed a 600 MWe core and studied the feasibility of the core concepts. Two additional scopes were performed in this project : study on the operational strategies of soluble boron free core and conceptual design of large scale passive core. By using the axial BP zoning concept and suitable design of control rods, this project showed that it was possible to design a soluble boron free core in 600 MWe PWR. The results of large scale core design showed that passive concepts and daily load follow operation could be practiced. (author). 15 refs., 52 tabs., 101 figs.
Punctured torus groups and 2-bridge knot groups
Akiyoshi, Hirotaka; Wada, Masaaki; Yamashita, Yasushi
2007-01-01
This monograph is Part 1 of a book project intended to give a full account of Jorgensen's theory of punctured torus Kleinian groups and its generalization, with application to knot theory. Although Jorgensen's original work was not published in complete form, it has been a source of inspiration. In particular, it has motivated and guided Thurston's revolutionary study of low-dimensional geometric topology. In this monograph, we give an elementary and self-contained description of Jorgensen's theory with a complete proof. Through various informative illustrations, readers are naturally led to an intuitive, synthetic grasp of the theory, which clarifies how a very simple fuchsian group evolves into complicated Kleinian groups.
Pointwise Behavior of the Linearized Boltzmann Equation on Torus
Wu, Kung-Chien
2013-01-01
We study the pointwise behavior of the linearized Boltzmann equation on torus for non-smooth initial perturbation. The result reveals both the fluid and kinetic aspects of this model. The fluid-like waves are constructed as part of the long-wave expansion in the spectrum of the Fourier mode for the space variable, the time decay rate of the fluid-like waves depends on the size of the domain. We design a Picard-type iteration for constructing the increasingly regular kinetic-like waves, which ...
Soliton scattering in the O(3) model on a torus
Cova, R. J.; Zakrzewski, W. J.
1997-01-01
Using numerical simulations, the stability and scattering properties of the O(3) model on a two-dimensional torus are studied. Its solitons are found to be unstable but can be stabilized by the addition of a Skyrme term to the Lagrangian. Scattering at right angles with respect to the initial direction of motion is observed in all cases considered. The model has no solutions of degree one, so when a field configuration that resembles a soliton is considered, it shrinks to become infinitely th...
Design Study on the Advanced Recycling Reactor
International Nuclear Information System (INIS)
The design study on the Advanced Recycling Reactor (ARR) has been conducted. This paper presents the pre-conceptual design of the ARR that is a loop-typed sodium cooled reactor with MOX fuel. International Nuclear Recycling Alliance (INRA) takes advantage of international experience and uses the design based on Japan Sodium-cooled Fast Reactor (JSFR) as reference for FOA studies of DOE in the U.S., because Japan has conducted R and Ds for the JSFR incorporating thirteen technology enhancements expected to improve safety, enhance economics, and increase reactor reliability. ARR's goal is to generate electricity while consuming fuel containing transuranics and to be cost-competitive with LWRs of similar size. INRA proposes 3 evolutions of the ARR; ARR1, a 500 MWe demonstration plant, online in 2025; ARR2, a 1,000 MWe commercial plant, online in 2035; ARR3, a 1,500 MWe full-scale commercial plant, online in 2050. INRA believes the scale-up factor of two is acceptable increase from manufacturing and licensing points of view. Major features of the ARR1 are the following: The reactor core of 70 cm high is working for a burner of TRU. The conversion ratio of fissile is set up less than 0.6 and the amount of burned TRU is 45-51 kg/TWeh. Decay heat can be removed by natural circulation to improve safety. The primary cooling system consists of two-loop arrangement and the integrated IHX/Pump to improve economics. The steam generator with the straight doublewalled tube is used to improve reliability. The capital cost, the construction schedule and regulatory and licensing schedule are estimated. Furthermore, the technology readiness level and the technology development roadmap are studied and identified to be ready for commercial deployment. (author)
Mirror Advanced Reactor Study engineering overview
International Nuclear Information System (INIS)
The Mirror Advanced Reactor Study (MARS) was the first comprehensive conceptual design of a commercial tandem mirror reactor with thermal barriers. The design exploited the inherent attractive features of a tandem mirror: steady state operation, linear central cell, simple high performance blankets, low first wall heat fluxes, natural impurity diversion by the halo plasma, no driven plasma currents or associated disruptions, and direct conversion of the charged particle power lost out the ends. The study introduced new design concepts in high field magnets, neutral beams, ECRH systems, drift pumping, direct conversion, lithium-lead blankets and plant safety. The MARS design would produce 1200 MWsub(e) net and more than 1500 MWsub(e) gross from only 2600 MW of fusion power. This high efficiency is achieved through a combination of blanket design and direct conversion. Special emphasis was placed on fusion's potential for inherent safety, lower activation and simpler disposal of radioactive waste as compared with fission. The blanket has a very low tritium inventory, cannot melt in loss-of-coolant and/or loss-of-flow accidents and can be disposed of as low level waste subject to near-surface burial. MARS would produce busbar electricity at about 7 cents per kilowatthour (constant 1983 dollars). This value is near the upper end of the cost range for new generation capability being installed in the late 1980's. Significant cost reductions can be gained by further improvements in the engineering designs combined with a simplified end cell. The largest cost reductions from engineering can be attained through redesigned magnets, heat transport system and electrical system. The combination of engineering and physics improvements are projected to lower the cost of electricity by about 40% without sacrificing the environmental, safety and maintainability attributes of MARS. This work is now being pursued in the MINIMARS study. (orig.)
NATO Advanced Study Institute on Spectroscopy
DiBartolo, Baldassare; Barnes, James (Technical Monitor)
2001-01-01
This booklet presents an account of the course 'Spectroscopy of Systems with Spatially Confined Structures' held in Erice-Sicily, Italy, from June 15 to June 30, 2001. This meeting was organized by the International School of Atomic and Molecular Spectroscopy of the 'Ettore Majorana' Centre for Scientific Culture. The purpose of this course was to present and discuss nanometer-scale physics, a rapidly progressing field. The top-down approach of semiconductor technology will soon meet the scales of the bottom-up approaches of supramolecular chemistry and of spatially localized excitations in ionic crystals. This course dealt with the fabrication, measurement and understanding of the relevant structures and brought together the scientific communities responsible for these development. The advances in this area of physics have already let to applications in optoelectronics and will likely lead to many more. The subjects of the course included spatially resolved structures such as quantum wells, quantum wires and quantum dots, single atoms and molecules, clusters, fractal systems, and the development of related techniques like near-field spectroscopy and confocal microscopy to study such systems.
Conceptual study on advanced PWR system
International Nuclear Information System (INIS)
In this study, the adoptable essential technologies and reference design concept of the advanced reactor were developed and related basic experiments were performed. 1) Once-through Helical Steam Generator: a performance analysis computer code for heli-coiled steam generator was developed for thermal sizing of steam generator and determination of thermal-hydraulic parameters. 2) Self-pressurizing pressurizer : a performance analysis computer code for cold pressurizer was developed. 3) Control rod drive mechanism for fine control : type and function were surveyed. 4) CHF in passive PWR condition : development of the prediction model bundle CHF by introducing the correction factor from the data base. 5) Passive cooling concepts for concrete containment systems: development of the PCCS heat transfer coefficient. 6) Steam injector concepts: analysis and experiment were conducted. 7) Fluidic diode concepts : analysis and experiment were conducted. 8) Wet thermal insulator : tests for thin steel layers and assessment of materials. 9) Passive residual heat removal system : a performance analysis computer code for PRHRS was developed and the conformance to EPRI requirement was checked. (author). 18 refs., 55 tabs., 137 figs
Energy Technology Data Exchange (ETDEWEB)
Fouchard, S
2006-04-15
Considering the recent increase in energy consumption. aide associated environmental risks, new trails are followed today to develop the use of clean and renewable alternative energies. In this context hydrogen seems to be a serious solution and this study, based on micro-algae photosynthetic capacities exploitation, will allow to devise a process for hydrogen production from only water and solar energy without greenhouse gas release. The sulphur deprivation protocol on TAP medium, known to lead to hydrogen production in Chlamydomonas reinhardtii species was particularly studied. At the metabolic level, two important phenomena are induced under these conditions: an over-accumulation of the intracellular starch reserves and a simultaneous alteration of the PsII activity which leads to anoxia and Fe-hydrogenase induction, an enzyme with a strong specific activity responsible for the hydrogen production. The contribution of the two electron transfer pathways implied in the hydrogen production process (PsII-dependent and PSII-independent) as well as the importance of the previously accumulated starch were highlighted here. We also investigated the potential for designing autotrophic protocols for hydrogen photoproduction. Various protocols, considered to be relevant, were then transposed on a torus photo-bioreactor, specifically developed in this study and which allows the control of culture parameters as well as the precise measurement of gas release kinetics, in order to obtain first estimates of productivity of the system. Integration of the physical; aspects of the pilot and biological aspects of the process in a model, finally opens new prospects for subject development, in particular for a reasoned optimization of hydrogen production via this double physiology/process approach. (author)
Institute of Scientific and Technical Information of China (English)
彭张立; 袁行飞; 董石麟
2007-01-01
在过去的六十年里,人们深入地研究了正圆柱形张拉整体结构和球形张拉整体结构,但对环形张拉整体结构的研究却很少见.本文对一种新型的环形张拉整体结构进行了初步的分析.首先介绍了这种环形张拉整体结构的拓扑,然后总结了该结构的找形步骤,并给出了一个初始预应力解析解算例,最后提出了一种以环形张拉整体结构作为环梁的新型索穹顶体系,分析了其结构性质.本文工作可为环形张拉整体结构的进一步研究和应用提供参考.%In the past sixty years, researches on cylindrical and spherical tensegrity modules were extensively carried out. However few studies on tensegrity torus are available. This paper presents an exploring study on a new kind of tensegrity torus. At first the topology of this kind of tensegrity torus is introduced. Then the initial form-finding procedure of tensegrity torus is summarized and a closed-form solution is given for a special example. As one of its applications, a new cable dome with a tensegrity torus as its ring beam is finally proposed and the structural behavior of this new dome is analyzed. The work here will provide a reference for further research and application of tensegrity torus.
International Nuclear Information System (INIS)
We study one-loop corrections in scalar and gauge field theories on the non-commutative torus. For rational θ, Morita equivalence allows these theories to be reformulated in terms of ordinary theories on a commutative torus with twisted boundary conditions. UV/IR mixing does not lead to singularities, however there can be large corrections. In particular, gauge theories show tachyonic instabilities for some of the modes. We discuss their relevance to spontaneous ZNxZN symmetry breaking in the Morita dual SU(N) theory due to electric flux condensation. (author)
Fermionic Zero Modes in Self-dual Vortex Background on a Torus
Institute of Scientific and Technical Information of China (English)
无
2007-01-01
We study fermionic zero modes in the self-dual vortex background on an extra two-dimensional Riemann surface in (5+1) dimensions. Using the generalized Abelian-Higgs model, we obtain the inner topological structure of the self-dual vortex and establish the exact self-duality equation with topological term. Then we analyze the Dirac operator on an extra torus and the effective Lagrangian of four-dimensional fermions with the self-dual vortex background. Solving the Dirac equation, the fermionic zero modes on a torus with the self-dual vortex background in two simple cases are obtained.
Advanced SFR Concept Design Studies at KAERI
International Nuclear Information System (INIS)
Advanced SFR design concepts have been developed which satisfy the Gen IV technology goals at KAERI. Two types of reactor core were developed for breakeven and TRU burner and both cores do not have blankets to enhance proliferation resistance. The Advanced SFR is a pool-type reactor that improves system safety through slow system transients. The heat transport system adopts two double wall tube Steam Generators and a passive Residual Heat Removal System PDRC. To secure the economic competitiveness of an SFR, the diameter of the reactor vessel of the Advanced SFR is designed to be 14.5 m, which is a very compact size compared to other designs. Also, various R and D activities have been performed in order to prepare some analysis tools and to support the development of design concepts. (author)
Neoadjuvant chemotherapy in advanced epithelial ovarian cancer: A survival study
Upasana Baruah; Debabrata Barmon; Amal Chandra Kataki; Pankaj Deka; Munlima Hazarika; Bhargab J Saikia
2015-01-01
Context: Patients with advanced ovarian cancer have a poor prognosis in spite of the best possible care. Primary debulking surgery has been the standard of care in advanced ovarian cancer; however, it is associated with high mortality and morbidity rates as shown in various studies. Several studies have discussed the benefit of neoadjuvant chemotherapy in patients with advanced ovarian cancer. Aims: This study aims to evaluate the survival statistics of the patients who have been managed with...
Overview of Results from the National Spherical Torus Experiment (NSTX)
International Nuclear Information System (INIS)
The mission of NSTX is the demonstration of the physics basis required to extrapolate to the next steps for the spherical torus (ST), such as a plasma facing component test facility (NHTX) or an ST based component test facility (ST-CTF), and to support ITER. Key issues for the ST are transport, and steady state high β operation. To better understand electron transport, a new high-k scattering diagnostic was used extensively to investigate electron gyro-scale fluctuations with varying electron temperature gradient scale-length. Results from n = 3 braking studies are consistent with the flow shear dependence of ion transport. New results from electron Bernstein wave emission measurements from plasmas with lithium wall coating applied indicate transmission efficiencies near 70% in H-mode as a result of reduced collisionality. Improved coupling of High Harmonic Fast-Waves has been achieved by reducing the edge density relative to the critical density for surface wave coupling. In order to achieve high bootstrap current fraction, future ST designs envision running at very high elongation. Plasmas have been maintained on NSTX at very low internal inductance li ∼ 0.4 with strong shaping (κ ∼ 2.7, (delta) ∼ 0.8) with βN approaching the with-wall beta limit for several energy confinement times. By operating at lower collisionality in this regime, NSTX has achieved record non-inductive current drive fraction fNI ∼ 71%. Instabilities driven by super-Alfvenic ions will be an important issue for all burning plasmas, including ITER. Fast ions from NBI on NSTX are super-Alfvenic. Linear TAE thresholds and appreciable fast-ion loss during multi-mode bursts are measured and these results are compared to theory. The impact of n > 1 error fields on stability is a important result for ITER. RWM/RFA feedback combined with n=3 error field control was used on NSTX to maintain plasma rotation with β above the no-wall limit. Other highlights are: results of lithium coating
Overview of Results from the National Spherical Torus Experiment (NSTX)
Energy Technology Data Exchange (ETDEWEB)
Gates, D; Ahn, J; Allain, J; Andre, R; Bastasz, R; Bell, M; Bell, R; Belova, E; Berkery, J; Betti, R; Bialek, J; Biewer, T; Bigelow, T; Bitter, M; Boedo, J; Bonoli, P; Bozzer, A; Brennan, D; Breslau, J; Brower, D; Bush, C; Canik, J; Caravelli, G; Carter, M; Caughman, J; Chang, C; Choe, W; Crocker, N; Darrow, D; Delgado-Aparicio, L; Diem, S; D' Ippolito, D; Domier, C; Dorland, W; Efthimion, P; Ejiri, A; Ershov, N; Evans, T; Feibush, E; Fenstermacher, M; Ferron, J; Finkenthal, M; Foley, J; Frazin, R; Fredrickson, E; Fu, G; Funaba, H; Gerhardt, S; Glasser, A; Gorelenkov, N; Grisham, L; Hahm, T; Harvey, R; Hassanein, A; Heidbrink, W; Hill, K; Hillesheim, J; Hillis, D; Hirooka, Y; Hosea, J; Hu, B; Humphreys, D; Idehara, T; Indireshkumar, K; Ishida, A; Jaeger, F; Jarboe, T; Jardin, S; Jaworski, M; Ji, H; Jung, H; Kaita, R; Kallman, J; Katsuro-Hopkins, O; Kawahata, K; Kawamori, E; Kaye, S; Kessel, C; Kim, J; Kimura, H; Kolemen, E; Krasheninnikov, S; Krstic, P; Ku, S; Kubota, S; Kugel, H; La Haye, R; Lao, L; LeBlanc, B; Lee, W; Lee, K; Leuer, J; Levinton, F; Liang, Y; Liu, D; Luhmann, N; Maingi, R; Majeski, R; Manickam, J; Mansfield, D; Maqueda, R; Mazzucato, E; McCune, D; McGeehan, B; McKee, G; Medley, S; Menard, J; Menon, M; Meyer, H; Mikkelsen, D; Miloshevsky, G; Mitarai, O; Mueller, D; Mueller, S; Munsat, T; Myra, J; Nagayama, Y; Nelson, B; Nguyen, X; Nishino, N; Nishiura, M; Nygren, R; Ono, M; Osborne, T; Pacella, D; Park, H; Park, J; Paul, S; Peebles, W; Penaflor, B; Peng, M; Phillips, C; Pigarov, A; Podesta, M; Preinhaelter, J; Ram, A; Raman, R; Rasmussen, D; Redd, A; Reimerdes, H; Rewoldt, G; Ross, P; Rowley, C; Ruskov, E; Russell, D; Ruzic, D; Ryan, P; Sabbagh, S; Schaffer, M; Schuster, E; Scott, S; Shaing, K; Sharpe, P; Shevchenko, V; Shinohara, K; Sizyuk, V; Skinner, C; Smirnov, A; Smith, D; Smith, S; Snyder, P; Soloman, W; Sontag, A; Soukhanovskii, V; Stoltzfus-Dueck, T; Stotler, D; Strait, T; Stratton, B; Stutman, D; Takahashi, R; Takase, Y; Tamura, N; Tang, X; Taylor, G; Taylor, C; Ticos, C; Tritz, K; Tsarouhas, D; Turrnbull, A; Tynan, G; Ulrickson, M; Umansky, M; Urban, J; Utergberg, E; Walker, M; Wampler, W; Wang, J; Wang, W; Weland, A
2009-01-05
The mission of NSTX is the demonstration of the physics basis required to extrapolate to the next steps for the spherical torus (ST), such as a plasma facing component test facility (NHTX) or an ST based component test facility (ST-CTF), and to support ITER. Key issues for the ST are transport, and steady state high {beta} operation. To better understand electron transport, a new high-k scattering diagnostic was used extensively to investigate electron gyro-scale fluctuations with varying electron temperature gradient scale-length. Results from n = 3 braking studies confirm the flow shear dependence of ion transport. New results from electron Bernstein wave emission measurements from plasmas with lithium wall coating applied indicate transmission efficiencies near 70% in H-mode as a result of reduced collisionality. Improved coupling of High Harmonic Fast-Waves has been achieved by reducing the edge density relative to the critical density for surface wave coupling. In order to achieve high bootstrap fraction, future ST designs envision running at very high elongation. Plasmas have been maintained on NSTX at very low internal inductance l{sub i} {approx} 0.4 with strong shaping ({kappa} {approx} 2.7, {delta} {approx} 0.8) with {beta}{sub N} approaching the with-wall beta limit for several energy confinement times. By operating at lower collisionality in this regime, NSTX has achieved record non-inductive current drive fraction f{sub NI} {approx} 71%. Instabilities driven by super-Alfvenic ions are an important issue for all burning plasmas, including ITER. Fast ions from NBI on NSTX are super-Alfvenic. Linear TAE thresholds and appreciable fast-ion loss during multi-mode bursts are measured and these results are compared to theory. RWM/RFA feedback combined with n = 3 error field control was used on NSTX to maintain plasma rotation with {beta} above the no-wall limit. The impact of n > 1 error fields on stability is a important result for ITER. Other highlights are
Overview of Results from the National Spherical Torus Experiment (NSTX)
Energy Technology Data Exchange (ETDEWEB)
Gates, D. A.; Ahn, J.; Allain, J.; Andre, R.; Bastasz, R.; Bell, M.; Bell, R.; Belova, E.; Berkery, J.; Betti, R.; Bialek, J.; Biewer, T.; Bigelow, T.; Bitter, M.; Choe, W.; Crocker, N.; Darrow, D.; Delgado-Aparicio, L.; Diem, S.; D’Ippolito, D.; Domier, C.; Dorland, W.; Efthimion, P.; Ejiri, A.; Ershov, N.; Evans, T.; Feibush, E.; Fenstermacher, M.; Ferron, J.; Finkenthal, M.; Foley, J.; Frazin, R.; Fredrickson, E.; Fu, G.; Funaba, H.; Gerhardt, S.; Glasser, A.; Gorelenkov, N.; Grisham, L.; Hahm, T.; Harvey, R.; Hassanein, A.; Heidbrink, W.; Hill, K.; Hillesheim, J.; Hillis, D.; Hirooka, Y.; Hu, B.; Humphreys, D.; Idehara, T.; Indireshkumar, K.; Ishida, A.; Jaeger, F.; Jarboe, T.; Jardin, S.; Jaworski, M.; Ji, H.; Jung, H.; Kaita, R.; Kallman, J.; Katsuro-Hopkins, O.; Kawahata, K.; Kawamori, E.; Kaye, S.; Kessel, C.; Kim, J.; Kimura, H.; Kolemen, E.; Krasheninnikov, S.; Krstic, P.; Ku, S.; Kubota, S.; Kugel, H.; La Haye, R.; Lao, L.; LeBlanc, B.; Lee, W.; Lee, K.; Leuer, J.; Levinton, F.; Liang, Y.; Liu, D.; Luhmann, Jr., N.; Maingi, R.; Majeski, R.; Manickam, J.; Mansfield, D.; Maqueda, R.; Mazzucato, E.; McCune, D.; McGeehan, B.; McKee, G.; Medley, S.; Menard, J.; Menon, M.; Meyer, H.; Mikkelsen, D.; Miloshevsky, G.; Mitarai, O.; Mueller, D.; Mueller, S.; Munsat, T.; Myra, J.; Nagayama, Y.; Nelson, B.; Nguyen, X.; Nishino, N.; Nishiura, M.; Nygren, R.; Ono, M.; Osborne, T.; Pacella, D.; Park, H.; Park, J.; Paul, S.; Peebles, W.; Penaflor, B.; Peng, M.; Phillips, C.; Pigarov, A.; Podesta, M.; Preinhaelter, J.; Ram, A.; Raman, R.; Rasmussen, D.; Redd, A.; Reimerdes, H.; Rewo, G.; Ross, P.; Rowley, C.; Ruskov, E.; Russell, D.; Ruzic, D.; Ryan, P.; Sabbagh, S.; Schaffer, M.; Schuster, E.; Scott, S.; Shaing, K.; Sharpe, P.; Shevchenko, V.; Shinohara, K.; Sizyuk, V.; Skinner, C.; Smirnov, A.; Smith, D.; Smith, S.; Snyder, P.; Solomon, W.; Sontag, A.; Soukhanovskii, V.; Stoltzfus-Dueck, T.; Stotler, D.; Strait, T.; Stratton, B.; Stutman, D.; Takahashi, R.; Takase, Y.; Tamura, N.; Tang, X.; Taylor, G.; Taylor, C.; Ticos, C.; Tritz, K.; Tsarouhas, D.; Turrnbull, A.; Tynan, G.; Ulrickson, M.; Umansky, M.; Urban, J.; Utergberg, E.; Walker, M.; Wampler, W.; Wang, J.; Wang, W.; Welander, A.; Whaley, J.; White, R.; Wilgen, J.; Wilson, R.; Wong, K.; Wright, J.; Xia, Z.; Xu, X.; Youchison, D.; Yu, G.; Yuh, H.; Zakharov, L.; Zemlyanov, D.; Zweben, S.
2009-03-24
The mission of NSTX is the demonstration of the physics basis required to extrapolate to the next steps for the spherical torus (ST), such as a plasma facing component test facility (NHTX) or an ST based component test facility (ST-CTF), and to support ITER. Key issues for the ST are transport, and steady state high β operation. To better understand electron transport, a new high-k scattering diagnostic was used extensively to investigate electron gyro-scale fluctuations with varying electron temperature gradient scale-length. Results from n = 3 braking studies are consistent with the flow shear dependence of ion transport. New results from electron Bernstein wave emission measurements from plasmas with lithium wall coating applied indicate transmission efficiencies near 70% in H-mode as a result of reduced collisionality. Improved coupling of High Harmonic Fast-Waves has been achieved by reducing the edge density relative to the critical density for surface wave coupling. In order to achieve high bootstrap current fraction, future ST designs envision running at very high elongation. Plasmas have been maintained on NSTX at very low internal inductance l_{i} ~0.4 with strong shaping (κ ~ 2.7, δ ~ 0.8) with β_{N} approaching the with-wall beta limit for several energy confinement times. By operating at lower collisionality in this regime, NSTX has achieved record non-inductive current drive fraction f_{NI} ~71%. Instabilities driven by super-Alfv´enic ions will be an important issue for all burning plasmas, including ITER. Fast ions from NBI on NSTX are super-Alfv´enic. Linear TAE thresholds and appreciable fast-ion loss during multi-mode bursts are measured and these results are compared to theory. The impact of n > 1 error fields on stability is a important result for ITER. RWM/RFA feedback combined with n=3 error field control was used on NSTX to maintain plasma rotation with β above the no-wall limit. Other highlights are: results
Design study on the Advanced Recycling Reactor
International Nuclear Information System (INIS)
Full text: The design study on the Advanced Recycling Reactor (ARR) has been conducted. This paper presents the pre-conceptual design of the ARR that is a loop-typed sodium cooled reactor with MOX fuel. International Nuclear Recycling Alliance (INRA) takes advantage of international experience and uses the design based on Japan Sodium-cooled Fast Reactor (JSFR) as reference for FOA studies of US DOE, because Japan has conducted R and Ds for the JSFR incorporating thirteen technology enhancements expected to improve safety, enhance economics, and increase reactor reliability. The targets of the ARR are to generate electricity while consuming fuel containing transuranics and to attain cost competitiveness with the similar sized LWRs. INRA proposes 3 evolutions of the ARR; ARR1, a 500 MWe demonstration plant, online in 2025; ARR2, a 1,000 MWe commercial plant, online in 2035; ARR3, a 1,500 MWe full-scale commercial plant, online in 2050. INRA believes the scale-up factor of two is acceptable increase from manufacturing and licensing points of view. Major features of the ARR1 are the following: The reactor core is 70cm high and the volume fraction of fuel is approximately 32%. The conversion ratio of fissile is set up less than 0.6 and the amount of burned TRU is 45-51 kg/TWeh.Decay heat can be removed by natural circulation to improve safety. The primary cooling system consists of two-loop arrangement and the integrated IHX/Pump to improve economics. The steam generator with the straight double-walled tube is used to improve reliability. The ARR1 is co-located with a recycling facility. The overall plant facility arrangement is planned assuming to be constructed and installed in an inland area. The plant consists of a reactor building (including reactor auxiliary facilities and electrical/control systems), a turbine building, and a recycling building. The volume of the reactor building will be approximately 180,000 m3. The capital cost for the ARR1 and the ARR2 are
The Schwinger model on the Torus
S. I, Azakov
1996-01-01
The classical and quantum aspects of the Schwinger model on the torus are considered. First we find explicitly all zero modes of the Dirac operator in the topological sectors with nontrivial Chern index and is spectrum. In the second part we determine the regularized effective action and discuss the propagators related to it. Finally we calculate the gauge invariant averages of the fermion bilinears and correlation functions of currents and densities. We show that in the infinite volume limit...
Oliversen, Ronald J.; Scherb, Frank; Roesler, Fred L.
1986-01-01
A Fabry-Perot spectrometer was used to obtain images of the Io torus in emission lines of S II (wavelength 6716 and 6731) and S III (wavelength 9531) in February and March 1981, on the 2.1 meter telescope at KPNO. The S II and S III images showed a large variation in brightness and radial extent. There is an indication the S II and S III emissions in the warm torus are correlated. The S II and S III emissions in the warm torus also have similar scale heights along the magnetic field lines of approximately 0.6 to 0.72 R sub J. The east-west asymmetry in the S II images taken at similar magnetic longitudes, but 2.5 Jovian rotations apart, supports the theory of convective motions suggested by others. In addition to the images, simultaneous measurements of the S II (6731 wavelength) line profile were also made on one night using a Fabry-Perot scanning spectrometer on the 4 meter at KPNO. The S II spectral scans implied ion temperatures of 52 (+ or - 10) x 10 to the 3rd at 5.2 to 5.6 R sub J from Jupiter and a minimum temperature of at least 3 x 10 to the 5th K at 6 R sub J from Jupiter.
The Phobos neutral and ionized torus
Poppe, A. R.; Curry, S. M.; Fatemi, S.
2016-05-01
Charged particle sputtering, micrometeoroid impact vaporization, and photon-stimulated desorption are fundamental processes operating at airless surfaces throughout the solar system. At larger bodies, such as Earth's Moon and several of the outer planet moons, these processes generate tenuous surface-bound exospheres that have been observed by a variety of methods. Phobos and Deimos, in contrast, are too gravitationally weak to keep ejected neutrals bound and, thus, are suspected to generate neutral tori in orbit around Mars. While these tori have not yet been detected, the distribution and density of both the neutral and ionized components are of fundamental interest. We combine a neutral Monte Carlo model and a hybrid plasma model to investigate both the neutral and ionized components of the Phobos torus. We show that the spatial distribution of the neutral torus is highly dependent on each individual species (due to ionization rates that span nearly 4 orders of magnitude) and on the location of Phobos with respect to Mars. Additionally, we present the flux distribution of torus pickup ions throughout the Martian system and estimate typical pickup ion fluxes. We find that the predicted pickup ion fluxes are too low to perturb the ambient plasma, consistent with previous null detections by spacecraft around Mars.
Gravitational potential of a homogeneous circular torus: new approach
Bannikova, Elena Yu; Shulga, Valery M
2010-01-01
The integral expression for gravitational potential of a homogeneous circular torus composed of infinitely thin rings is obtained. Approximate expressions for torus potential in the outer and inner regions are found. In the outer region a torus potential is shown to be approximately equal to that of an infinitely thin ring of the same mass; it is valid up to the surface of the torus. It is shown in a first approximation, that the inner potential of the torus (inside a torus body) is a quadratic function of coordinates. The method of sewing together the inner and outer potentials is proposed. This method provided a continuous approximate solution for the potential and its derivatives, working throughout the region.
Advanced nuclear systems. Review study; Fortgeschrittene Nuklearsysteme. Review Study
Energy Technology Data Exchange (ETDEWEB)
Liebert, Wolfgang; Glaser, Alexander; Pistner, Christoph [Interdisziplinaere Arbeitsgruppe Naturwissenschaft, Technik und Sicherheit (IANUS), Darmstadt University of Technology, Hochschulstrasse 10, D-64289 Darmstadt (Germany); Baehr, Roland; Hahn, Lothar [Institute for applied ecology (Oeko-Institut), Elisabethenstrasse 55-57, D-64283 Darmstadt (Germany)
1999-04-01
The task of this review study is to from provide an overview of the developments in the field of the various advanced nuclear systems, and to create the basis for more comprehensive studies of technology assessment. In an overview the concepts for advanced nuclear systems pursued worldwide are subdivided into eight subgroups. A coarse examination raster (set pattern) is developed to enable a detailed examination of the selected systems. In addition to a focus on enhanced safety features, further aspects are also taken into consideration, like the lowering of the proliferation risk, the enhancement of the economic competitiveness of the facilities and new usage possibilities (for instance concerning the relaxation of the waste disposal problem or the usage of alternative fuels to uranium). The question about the expected time span for realization and the discussion about the obstacles on the way to a commercially usable reactor also play a substantial role as well as disposal requirements as far as they can be presently recognized. In the central chapter of this study, the documentation of the representatively selected concepts is evaluated as well as existing technology assessment studies and expert opinions. In a few cases where this appears to be necessary, according technical literature, further policy advisory reports, expert statements as well as other relevant sources are taken into account. Contradictions, different assessments and dissents in the literature as well as a few unsettled questions are thus indicated. The potential of advanced nuclear systems with respect to economical and societal as well as environmental objectives cannot exclusively be measured by the corresponding intrinsic or in comparison remarkable technical improvements. The acceptability of novel or improved systems in nuclear technology will have to be judged by their convincing solutions for the crucial questions of safety, nuclear waste and risk of proliferation of nuclear weapons
Orientability and equivariant oriented cobordism of 2-torus manifolds
Sarkar, Soumen
2010-01-01
We give a necessary and sufficient condition for the orientability of a locally standard 2-torus manifold with a fixed point which generalizes previous results of Nakayama-Nishimura in 2005 and Soprunova-Sottile in 2013. We construct manifolds with boundary where the boundary is a disjoint union of locally standard 2-torus manifolds. We discuss equivariant oriented cobordism class of locally standard 2-torus manifolds.
Circuit-Switched Gossiping in the 3-Dimensional Torus Networks
Delmas, Olivier; Pérennes, Stéphane
1996-01-01
In this paper we describe, in the case of short messages, an efficient gossiping algorithm for 3-dimensional torus networks (wrap-around or toroidal meshes) that uses synchronous circuit-switched routing. The algorithm is based on a recursive decomposition of a torus. The algorithm requires an optimal number of rounds and a quasi-optimal number of intermediate switch settings to gossip in an $7^i \\times 7^i \\times 7^i$ torus.
Performance Metrics Analysis of Torus Embedded Hypercube Interconnection Network
Directory of Open Access Journals (Sweden)
N. Gopalakrishna Kini
2009-09-01
Full Text Available Advantages of hypercube network and torus topology are used to derive an embedded architecture for product network known as torus embedded hypercube scalable interconnection network. This paper analyzes torus embedded hypercube network pertinent to parallel architecture. The network metrics are used to show how good embedded network can be designed for parallel computation. Network parameter analysis and comparison of embedded network with basic networks is presented.
Scrieciu, Monica; MercuŢ, Veronica; MercuŢ, Răzvan; Bîrjovanu, Carrol; Stan, Mihaela Cristina; Marinescu, Iulia Roxana; Niculescu, Mihaela; Iorgulescu, Daniel; Bătăiosu, Marilena
2016-01-01
The oral exostoses are protuberance located on the alveolar surfaces of the jawbones with nodular, flat or pedunculated shape. The purpose of this study was to highlight the variability of the morphological and clinical characteristics of torus palatinus (TP) and torus mandibularis (TM) in a sample of young and adults' Romanian people. The study was conducted on 74 participants examined in Dental Prosthetics Clinic of the Faculty of Dentistry, University of Medicine and Pharmacy of Craiova, Romania, during October-December 2014. The morphological characteristics of the tori were non-metrical evaluated by the standard procedures of the clinical examination. Descriptive statistics only including means, averages and percentage incidence have been used to describe the results. Of the 74 study participants, 31 (41.89%) were males and 43 (55.40%) were females. Six had only TP, seven had only TM and three participants had both TP and TM. The most of the palatal tori had spindle shaped, located in all area of the hard palate The round mandibular tori with big size were located in the area of both premolars, and those with elongate shape were located in the canine-premolars area. The palatal tori were more frequently in women and the frequency of mandibular tori was equally in men and women. Most of the palatal tori had spindle shape and most of the mandibular tori were solitary bilateral. PMID:27151699
High-spin torus isomers and their precession motions
Ichikawa, T.; Matsuyanagi, K.; Maruhn, J. A.; Itagaki, N.
2014-01-01
We systematically investigate the existence of exotic torus isomers and their precession motions for a series of $N=Z$ even-even nuclei from $^{28}$Si to $^{56}$Ni. We analyze the microscopic shell structure of the torus isomer and discuss why the torus shape is generated beyond the limit of large oblate deformation. We use the cranked three-dimensional Hartree-Fock (HF) method with various Skyrme interactions in a systematic search for high-spin torus isomers. We use the three-dimensional ti...
Overview of recent physics results from the National Spherical Torus Experiment (NSTX)
Energy Technology Data Exchange (ETDEWEB)
Menard, J. E.; Bell, M. G.; Bell, R. E.; Bernabei, S.; Bialek, J.; Biewer, T.; Blanchard, W.; Boedo, J.; Bush, C. E.; Carter, M. D.; Choe, W.; Crocker, N. A.; Darrow, D. S.; Davis, W.; Delgado-Aparicio, L.; Diem, S.; Domier, C. W.; D' Ippolito, D. A.; Ferron, J.; Field, A.; Foley, J.; Fredrickson, E. D.; Gates, D. A.; Gibney, T.; Harvey, R.; Hatcher, R. E.; Heidbrink, W.; Hill, K. W.; Hosea, J. C.; Jarboe, T. R.; Johnson, D. W.; Kaita, R.; Kaye, S. M.; Kessel, C. E.; Kubota, S.; Kugel, H. W.; Lawson, J.; LeBlanc, B. P.; Lee, K. C.; Levinton, F. M.; Luhmann, N. C.; Maingi, R.; Majeski, R. P.; Manickam, J.; Mansfield, D. K.; Maqueda, R.; Marsala, R.; Mastrovito, D.; Mau, T. K.; Mazzucato, E.; Medley, S. S.; Meyer, H.; Mikkelsen, D. R.; Mueller, D.; Munsat, T.; Myra, J. R.; Nelson, B. A.; Neumeyer, C.; Nishino, N.; Ono, M.; Park, H. K.; Park, W.; Paul, S. F.; Peebles, T.; Peng, M.; Phillips, C.; Pigarov, A.; Pinsker, R.; Ram, A.; Ramakrishnan, S.; Raman, R.; Rasmussen, D.; Redi, M.; Rensink, M.; Rewoldt, G.; Robinson, J.; Roney, P.; Roquemore, A. L.; Ruskov, E.; Ryan, P.; Sabbagh, S. A.; Schneider, H.; Skinner, C. H.; Smith, D. R.; Sontag, A.; Soukhanovskii, V.; Stevenson, T.; Stotler, D.; Stratton, B. C.; Stutman, D.; Swain, D.; Synakowski, E.; Takase, Y.; Taylor, G.; Tritz, K.; von Halle, A.; Wade, M.; White, R.; Wilgen, J.; Williams, M.; Wilson, J. R.; Yuh, H.; Zakharov, L. E.; Zhu, W.; Zweben, S. J.; Akers, R.; Beiersdorfer, P.; Betti, R.; Bigelow, T.; Bitter, M.; Bonoli, P.; Bourdelle, C.; Chang, C. S.; Chrzanowski, J.; Dudek, L.; Efthimion, P. C.; Finkenthal, M.; Fredd, E.; Fu, G. Y.; Glasser, A.; Goldston, R. J.; Greenough, N. L.; Grisham, L. R.; Gorelenkov, N.; Guazzotto, L.; Hawryluk, R. J.; Hogan, J.; Houlberg, W.; Humphreys, D.; Jaeger, F.; Kalish, M.; Krasheninnikov, S.; Lao, L. L.; Lawrence, J.; Leuer, J.; Liu, D.; Oliaro, G.; Pacella, D.; Parsells, R.; Schaffer, M.; Semenov, I.; Shaing, K. C.; Shapiro, M. A.; Shinohara, K.; Sichta, P.; Tang, X.; Vero, R.; Walker, M.; Wampler, W.
2007-10-01
The National Spherical Torus Experiment (NSTX) has made considerable progress in advancing the scientific understanding of high performance long-pulse plasmas needed for future spherical torus (ST) devices and ITER. Plasma durations up to 1.6 s (five current redistribution times) have been achieved at plasma currents of 0.7 MA with non-inductive current fractions above 65% while simultaneously achieving β_{T}and β_{N} values of 17% and 5.7 (%m T MA ^{-1}), respectively. A newly available motional Stark effect diagnostic has enabled validation of current-drive sources and improved the understanding of NSTX 'hybrid'-like scenarios. In MHD research, ex-vessel radial field coils have been utilized to infer and correct intrinsic EFs, provide rotation control and actively stabilize the n = 1 resistive wall mode at ITER-relevant low plasma rotation values. In transport and turbulence research, the low aspect ratio and a wide range of achievable β in the NSTX provide unique data for confinement scaling studies, and a new microwave scattering diagnostic is being used to investigate turbulent density fluctuations with wavenumbers extending from ion to electron gyro-scales. In energetic particle research, cyclic neutron rate drops have been associated with the destabilization of multiple large toroidal Alfven eigenmodes (TAEs) analogous to the 'sea-of-TAE' modes predicted for ITER, and three-wave coupling processes have been observed for the first time. In boundary physics research, advanced shape control has enabled studies of the role of magnetic balance in H-mode access and edge localized mode stability. Peak divertor heat flux has been reduced by a factor of 5 using an H-mode-compatible radiative divertor, and lithium conditioning has demonstrated particle pumping and results in improved thermal confinement. Finally, non-solenoidal plasma start-up experiments have achieved plasma currents of 160 kA on closed magnetic flux
Decommissioning planning for the Joint European Torus Fusion Reactor
International Nuclear Information System (INIS)
The Joint European Torus (JET) machine is an experimental nuclear fusion device built in the United Kingdom by a European consortium. Tritium was first introduced into the Torus as a fuel in 1991 and it is estimated that at the end of operations and following a period of tritium recovery there will be 2 grams of tritium in the vacuum circuit. All in-vessel items are also contaminated with beryllium and the structure of the machine is neutron activated. Decommissioning of the facility will commence immediately JET operations cease and the UKAEA's plan is to remove all the facilities and to landscape the site within 10 years. The decommissioning plan has been through a number of revisions since 1995 that have refined the detail, timescales and costs. The latest 2005 revision of the decommissioning plan highlighted the need to clarify the size reduction and packaging requirements for the ILW and LLW. Following a competitive tender exercise, a contract was placed by UKAEA with NUKEM Limited to undertake a review of the waste estimates and to produce a concept design for the planned size reduction and packaging facilities. The study demonstrated the benefit of refining decommissioning planning by increasing the detail as the decommissioning date approaches. It also showed how a review of decommissioning plans by independent personnel can explore alternative strategies and result in improved methodologies and estimates of cost and time. This paper aims to describe this part of the decommissioning planning process and draw technical and procedural conclusions. (authors)
The geometric Schwinger Model on the Torus II
Energy Technology Data Exchange (ETDEWEB)
Joos, H. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Azakov, S.I. [AN Azerbajdzhanskoj SSR, Baku (Azerbaijan). Inst. Fiziki]|[Institute for Advanced Studies in Basic Sciences, Zanjan (Iran, Islamic Republic of)
1994-08-01
The geometric Schwinger Model (gSM) is the theory of a U(1)-gauge field in two dimensions coupled to a massless Dirac Kaehler field. It is equivalent to a Schwinger model with Dirac fields {Phi}{sub a}{sup b}(x) carrying iso-spin 1/2. We consider this model on the Euclidean space time of a torus. In Part I we discussed in detail the zero mode structure of this model. The main aim of this Part is the calculation of the correlation functions of currents and densities. Since it turned out that the gSM illustrates the generally interesting structure of anomalous chiral symmetry breaking in a very transparent manner, we present our results in the more familiar language of Dirac fields. In the introduction to the first part of our investigations we mentioned as motivation for the study of the gSM on the torus the possibility of a systematic lattice approximation of this model. In the meanwhile this project was realized to a large extend. Here we give the details of the discussion of the different quantities in the continuum to which we applied the lattice approximation. For these we formulate the `geometric` description by differential forms of quantities which we consider interesting in this context. (orig.)
The geometric Schwinger Model on the Torus II
International Nuclear Information System (INIS)
The geometric Schwinger Model (gSM) is the theory of a U(1)-gauge field in two dimensions coupled to a massless Dirac Kaehler field. It is equivalent to a Schwinger model with Dirac fields Φab(x) carrying iso-spin 1/2. We consider this model on the Euclidean space time of a torus. In Part I we discussed in detail the zero mode structure of this model. The main aim of this Part is the calculation of the correlation functions of currents and densities. Since it turned out that the gSM illustrates the generally interesting structure of anomalous chiral symmetry breaking in a very transparent manner, we present our results in the more familiar language of Dirac fields. In the introduction to the first part of our investigations we mentioned as motivation for the study of the gSM on the torus the possibility of a systematic lattice approximation of this model. In the meanwhile this project was realized to a large extend. Here we give the details of the discussion of the different quantities in the continuum to which we applied the lattice approximation. For these we formulate the 'geometric' description by differential forms of quantities which we consider interesting in this context. (orig.)
Minimal fixed point set of maps on Torus Fiber Bundles over the Circle
Silva, Weslem L.
2013-01-01
The main purpose this work is to study the minimal fixed point set of fiber-preserving maps for spaces which are fiber bundles over the circle and the fiber is the torus. Using the one-parameter fixed point theory is possible to describe these sets in terms of the fundamental group and the induced homomorphism.
Generic uniqueness of a minimal solution for variational problems on a torus
Directory of Open Access Journals (Sweden)
Alexander J. Zaslavski
2002-03-01
Full Text Available We study minimal solutions for one-dimensional variational problems on a torus. We show that, for a generic integrand and any rational number ÃŽÂ±, there exists a unique (up to translations periodic minimal solution with rotation number ÃŽÂ±.
Soliton Gauge States and T-duality of Closed Bosonic String Compatified on Torus
Lee, Jen-Chi
2000-01-01
We study soliton gauge states in the spectrum of bosonic string compatified on torus. The enhenced Kac-Moody gauge symmetry, and thus T-duality, is shown to be related to the existence of these soliton gauge states in some moduli points.
Study of IMT-advanced heterogeneous network
Institute of Scientific and Technical Information of China (English)
Qin Fei; Peng Ying; Sun Shaohui; Wang Yingmin
2011-01-01
Referring to research on the Heterogeneous Network （Het-Net） application scenario and technique characters in IMT-Advaneed （The 4th Generation Mobile Communications） cellular system, this paper provides further analysis on main technique aspects of Heterogeneous Network, discussion on interference issue due to multi-layer building by access points and their corresponding solutions from standardization and engineering implementation. The proposed solution can effectively solve the interference problem in IMT-advanced Het-Net, and also improves the networking performance dramaticaUy for future mobile communication systems.
Skills Required for Nursing Career Advancement: A Qualitative Study
Sheikhi, Mohammad Reza; Fallahi-Khoshnab, Masoud; Mohammadi, Farahnaz; Oskouie, Fatemeh
2016-01-01
Background Nurses require certain skills for progression in their field. Identifying these skills can provide the context for nursing career advancement. Objectives This study aimed to identify the skills needed for nurses’ career advancement. Materials and Methods A qualitative approach using content analysis was adopted to study a purposive sample of eighteen nurses working in teaching hospitals affiliated with the Qazvin, Shahid Beheshti, and Iran Universities of Medical Sciences. The data were collected through semi-structured interviews, and analyzed using conventional content analysis. Results The three themes extracted from the data included interpersonal capabilities, competency for career success, and personal capacities. The results showed that acquiring a variety of skills is essential for career advancement. Conclusions The findings showed that personal, interpersonal, and functional skills can facilitate nurses’ career advancement. The effects of these skills on career advancement depend on a variety of conditions that require further studies. PMID:27556054
Advances in radiobiological studies using a microbeam
International Nuclear Information System (INIS)
Recent developments in microbeam technology have made drastic improvements in particle delivery, focusing, image processing and precision to allow for rapid advances in our knowledge in radiation biology. The unequivocal demonstration that targeted cytoplasmic irradiation results in mutations in the nuclei of hit cells and the presence of non-targeted effects, all made possible using a charged particle microbeam, results in a paradigm shift in our basic understanding of the target theory and other radiation-induced low dose effects. The demonstration of a bystander effect in 3D human tissue and whole organisms have shown the potential relevance of the non-targeted response in human health. The demonstration of delayed mutations in the progeny of bystander cells suggest that genomic instability induced following ionizing radiation exposure is not dependent on direct damage to cell nucleus. The identification of specific signaling pathways provides mechanistic insight on the nature of the bystander process. (author)
The Schwinger model on the Torus
Azakov, S I
1996-01-01
The classical and quantum aspects of the Schwinger model on the torus are considered. First we find explicitly all zero modes of the Dirac operator in the topological sectors with nontrivial Chern index and is spectrum. In the second part we determine the regularized effective action and discuss the propagators related to it. Finally we calculate the gauge invariant averages of the fermion bilinears and correlation functions of currents and densities. We show that in the infinite volume limit the well-known result for the chiral condensate can be obtained and the clustering property can be established.
The Schwinger Model on the torus
International Nuclear Information System (INIS)
The classical and quantum aspects of the Schwinger model on the torus are considered. First we find explicitly all zero modes of the Dirac operator in the topological sectors with nontrivial Chern index and its spectrum. In the second part we determine the regularized effective action and discuss the propagators related to it. Finally we calculate the gauge invariant averages of the fermion bilinears and correlation functions of currents and densities. We show that in the infinite volume limit the well-known result for the chiral condensate can be obtained and the clustering property can be established. (author). 23 refs
Ducks on the torus: existence and uniqueness
Schurov, Ilya
2009-01-01
We show that there exist generic slow-fast systems with only one (time-scaling) parameter on the two-torus, which have canard cycles for arbitrary small values of this parameter. This is in drastic contrast with the planar case, where canards usually occur in two-parametric families. Here we treat systems with a convex slow curve. In this case there is a set of parameter values accumulating to zero for which the system has exactly one attracting and one repelling canard cycle. The basin of th...
The AJ-conjecture and cabled knots over torus knots
Ruppe, Dennis; Zhang, Xingru
2014-01-01
We show that most cabled knots over torus knots in $S^3$ satisfy the AJ-conjecture, namely each $(r,s)$-cabled knot over each $(p,q)$-torus knot satisfies the $AJ$-conjecture if $r$ is not a number between $0$ and $pqs$.
Obstructions of Connectivity 2 for Embedding Graphs into the Torus
Mohar, Bojan; Škoda, Petr
2012-01-01
The complete set of minimal obstructions for embedding graphs into the torus is still not determined. In this paper, we present all obstructions for the torus of connectivity 2. Furthermore, we describe the building blocks of obstructions of connectivity 2 for any orientable surface.
High-spin torus isomers and their precession motions
Ichikawa, T; Maruhn, J A; Itagaki, N
2014-01-01
We systematically investigate the existence of exotic torus isomers and their precession motions for a series of $N=Z$ even-even nuclei from $^{28}$Si to $^{56}$Ni. We analyze the microscopic shell structure of the torus isomer and discuss why the torus shape is generated beyond the limit of large oblate deformation. We use the cranked three-dimensional Hartree-Fock (HF) method with various Skyrme interactions in a systematic search for high-spin torus isomers. We use the three-dimensional time-dependent Hartree-Fock (TDHF) method for describing the precession motion of the torus isomer. We obtain high-spin torus isomers in $^{36}$Ar, $^{40}$Ca, $^{44}$Ti, $^{48}$Cr, and $^{52}$Fe. The emergence of the torus isomers is associated with the alignments of single-particle angular momenta, which is the same mechanism as found in $^{40}$Ca. It is found that all the obtained torus isomers execute the precession motion at least two rotational periods. The moment of inertia about a perpendicular axis, which characteri...
Executive summary: advanced-fuel fusion systems, the D-3He satellite approach
International Nuclear Information System (INIS)
An evaluation was made of the potential advantages and feasibility of fusion power plants designed to employ near-term non-D--T fuels such as deuterium and D-3He. The following topics are discussed here: (1) cost studies and net-energy analysis, (2) D-3He Bumpy Torus satellite, (3) exploratory studies of a D-3He field-reversed mirror satellite, (4) preliminary advanced fuel pellet studies, and (5) 3He neutral beam injector
The clumpy torus around type II AGN as revealed by X-ray fluorescent lines
Liu, Jiren; Li, Xiaobo; Xu, Weiwei; Gou, Lijun; Cheng, Cheng
2016-01-01
The reflection spectrum of the torus around AGN is characterized by X-ray fluorescent lines, which are most prominent for type II AGN. A clumpy torus allows photons reflected from the back-side of the torus to leak through the front free-of-obscuration regions. Therefore, the observed X-ray fluorescent lines are sensitive to the clumpiness of the torus. We analyse a sample of type II AGN observed with Chandra HETGS, and measure the fluxes for the Si Ka and Fe Ka lines. The measured Fe Ka/Si Ka ratios, spanning a range between $5-60$, are far smaller than the ratios predicted from simulations of smooth tori, indicating that the tori of the studied sources have clumpy distributions rather than smooth ones. Compared with simulation results of clumpy tori with a half-opening angle of 60$^{\\circ}$, the Circinus galaxy has a Fe Ka/Si Ka ratio of $\\sim60$, which is close to the simulation results for $N=5$, where $N$ is the average number of clumps along the line of sight. The Fe Ka/Si Ka ratios of the other sources...
Observations of the He+ pickup ion torus velocity distribution function with SOHO/CELIAS/CTOF
Taut, Andreas; Berger, Lars; Bochsler, Peter; Drews, Christian; Klecker, Berndt; Wimmer-Schweingruber, Robert F.
2016-03-01
Interstellar PickUp Ions (PUIs) are created from neutrals coming from the interstellar medium that get ionized inside the heliosphere. Once ionized, the freshly created ions are injected into the magnetized solar wind plasma with a highly anisotropic torus-shaped Velocity Distribution Function (VDF). It has been commonly assumed that wave-particle interactions rapidly destroy this torus by isotropizing the distribution in one hemisphere of velocity space. However, recent observations of a He+ torus distribution using PLASTIC on STEREO showed that the assumption of a rapid isotropization is oversimplified. The aim of this work is to complement these studies. Using He+ data from the Charge Time-Of-Flight (CTOF) sensor of the Charge, ELement, and Isotope Analysis System (CELIAS) on-board the SOlar and Heliospheric Observatory (SOHO) and magnetic field data from the Magnetic Field Investigation (MFI) magnetometer of the WIND spacecraft, we derive the projected 1-D VDF of He+ for different magnetic field configurations. Depending on the magnetic field direction, the initial torus VDF lies inside CTOF's aperture or not. By comparing the VDFs derived under different magnetic field directions with each other we reveal an anisotropic signature of the He+ VDF.
High Performance Hierarchical Torus Network Under Adverse Traffic Patterns
Directory of Open Access Journals (Sweden)
MM Hafizur Rahman
2012-03-01
Full Text Available A Hierarchical Torus Network (HTN is a 2D-torus network of multiple basic modules, in which the basic modules are 3D-torus networks that are hierarchically interconnected for higher level networks. The dynamic communication performance of the HTN using the dimension-order routing under common traffic patterns have been evaluated, and have been shown to be good. However, dynamic communication performance of HTN under adverse traffic patterns has not been evaluated yet. In this paper, we evaluate the dynamic communication performance of HTN using a deadlock-free dimension order routing with 3 virtual channels under adverse traffic patterns, and compare it with H3D-mesh, mesh, and torus networks. It is shown that even under adverse traffic patterns, the HTN yields high throughput and low average transfer time, which provide better dynamic communication performance than H3D-mesh, mesh, and torus networks.
Compact torus experiments and theory
International Nuclear Information System (INIS)
Two types of compact toroids have been studied: spheromaks and field-reversed configurations (FRC). Spheromaks, which contain both toroidal and poloidal fields, have been formed with a magnetized coaxial injector and trapped in both prolate and oblate flux conservers. As expected from theory, the prolate configuration always tilts, but the oblate configuration can be made stable even in the presence of a guide field. Observations include 150μs lifetimes, approx. 1014 cm-3, and a decrease of field fluctuations by a factor of 100 at the time of complete reconnection. Theoretical studies of the FRC (no toroidal field) have been compared with the results of two field-reversed theta-pinches, FRX-A and FRX-B
Magnetic surfaces in an axisymmetric torus
International Nuclear Information System (INIS)
A method is developed for specifying the boundary equilibrium magnetic surface in an axially symmetric torus by using the absolute values of the magnetic field B = Bs(θ) and the gradient of the poloidal flux vertical bar vertical bar ∇Ψ vertical bar = vertical bar ∇Ψ vertical bar s(θ) in a special flux coordinate system. By setting two surface constants (e.g., the safety factor q and dp/dΨ) and matching the absolute values of the magnetic field and the flux gradient on a closed magnetic surface, it is possible to find all equilibrium magnetic functions (including n · ∇ ln B and the local shear s) and all constants (including the toroidal current J and the shear dμ/dΨ) on this surface. Such a non-traditional formulation of the boundary conditions in solving the stability problem in an axisymmetric torus allows one to impose intentional conditions on plasma confinement and MHD stability at the periphery of the system.
Arithmetic functions in torus and tree networks
Bhanot, Gyan; Blumrich, Matthias A.; Chen, Dong; Gara, Alan G.; Giampapa, Mark E.; Heidelberger, Philip; Steinmacher-Burow, Burkhard D.; Vranas, Pavlos M.
2007-12-25
Methods and systems for performing arithmetic functions. In accordance with a first aspect of the invention, methods and apparatus are provided, working in conjunction of software algorithms and hardware implementation of class network routing, to achieve a very significant reduction in the time required for global arithmetic operation on the torus. Therefore, it leads to greater scalability of applications running on large parallel machines. The invention involves three steps in improving the efficiency and accuracy of global operations: (1) Ensuring, when necessary, that all the nodes do the global operation on the data in the same order and so obtain a unique answer, independent of roundoff error; (2) Using the topology of the torus to minimize the number of hops and the bidirectional capabilities of the network to reduce the number of time steps in the data transfer operation to an absolute minimum; and (3) Using class function routing to reduce latency in the data transfer. With the method of this invention, every single element is injected into the network only once and it will be stored and forwarded without any further software overhead. In accordance with a second aspect of the invention, methods and systems are provided to efficiently implement global arithmetic operations on a network that supports the global combining operations. The latency of doing such global operations are greatly reduced by using these methods.
Advanced Burner Reactor Preliminary NEPA Data Study
International Nuclear Information System (INIS)
The Global Nuclear Energy Partnership (GNEP) is a new nuclear fuel cycle paradigm with the goals of expanding the use of nuclear power both domestically and internationally, addressing nuclear waste management concerns, and promoting nonproliferation. A key aspect of this program is fast reactor transmutation, in which transuranics recovered from light water reactor spent fuel are to be recycled to create fast reactor transmutation fuels. The benefits of these fuels are to be demonstrated in an Advanced Burner Reactor (ABR), which will provide a representative environment for recycle fuel testing, safety testing, and modern fast reactor design and safeguard features. Because the GNEP programs will require facilities which may have an impact upon the environment within the meaning of the National Environmental Policy Act of 1969 (NEPA), preparation of a Programmatic Environmental Impact Statement (PEIS) for GNEP is being undertaken by Tetra Tech, Inc. The PEIS will include a section on the ABR. In support of the PEIS, the Nuclear Engineering Division of Argonne National Laboratory has been asked to provide a description of the ABR alternative, including graphics, plus estimates of construction and operations data for an ABR plant. The compilation of this information is presented in the remainder of this report. Currently, DOE has started the process of engaging industry on the design of an Advanced Burner Reactor. Therefore, there is no specific, current, vendor-produced ABR design that could be used for this PEIS datacall package. In addition, candidate sites for the ABR vary widely as to available water, geography, etc. Therefore, ANL has based its estimates for construction and operations data largely on generalization of available information from existing plants and from the environmental report assembled for the Clinch River Breeder Reactor Plant (CRBRP) design [CRBRP, 1977]. The CRBRP environmental report was chosen as a resource because it thoroughly
Advanced Burner Reactor Preliminary NEPA Data Study.
Energy Technology Data Exchange (ETDEWEB)
Briggs, L. L.; Cahalan, J. E.; Deitrich, L. W.; Fanning, T. H.; Grandy, C.; Kellogg, R.; Kim, T. K.; Yang, W. S.; Nuclear Engineering Division
2007-10-15
The Global Nuclear Energy Partnership (GNEP) is a new nuclear fuel cycle paradigm with the goals of expanding the use of nuclear power both domestically and internationally, addressing nuclear waste management concerns, and promoting nonproliferation. A key aspect of this program is fast reactor transmutation, in which transuranics recovered from light water reactor spent fuel are to be recycled to create fast reactor transmutation fuels. The benefits of these fuels are to be demonstrated in an Advanced Burner Reactor (ABR), which will provide a representative environment for recycle fuel testing, safety testing, and modern fast reactor design and safeguard features. Because the GNEP programs will require facilities which may have an impact upon the environment within the meaning of the National Environmental Policy Act of 1969 (NEPA), preparation of a Programmatic Environmental Impact Statement (PEIS) for GNEP is being undertaken by Tetra Tech, Inc. The PEIS will include a section on the ABR. In support of the PEIS, the Nuclear Engineering Division of Argonne National Laboratory has been asked to provide a description of the ABR alternative, including graphics, plus estimates of construction and operations data for an ABR plant. The compilation of this information is presented in the remainder of this report. Currently, DOE has started the process of engaging industry on the design of an Advanced Burner Reactor. Therefore, there is no specific, current, vendor-produced ABR design that could be used for this PEIS datacall package. In addition, candidate sites for the ABR vary widely as to available water, geography, etc. Therefore, ANL has based its estimates for construction and operations data largely on generalization of available information from existing plants and from the environmental report assembled for the Clinch River Breeder Reactor Plant (CRBRP) design [CRBRP, 1977]. The CRBRP environmental report was chosen as a resource because it thoroughly
International Nuclear Information System (INIS)
In this work the correspondence between the semiclassical limit of the DOZZ quantum Liouville theory on the torus and the Nekrasov-Shatashvili limit of the N=2∗ (Ω-deformed) U(2) super-Yang-Mills theory is used to propose new formulae for the accessory parameter of the Lamé equation. This quantity is in particular crucial for solving the problem of uniformization of the one-punctured torus. The computation of the accessory parameters for torus and sphere is an open longstanding problem which can however be solved if one succeeds to derive an expression for the so-called classical Liouville action. The method of calculation of the latter has been proposed some time ago by Zamolodchikov brothers. Studying the semiclassical limit of the four-point function of the quantum Liouville theory on the sphere they have derived the classical action for the Riemann sphere with four punctures. In the present work Zamolodchikovs idea is exploited in the case of the Liouville field theory on the torus. It is found that the Lamé accessory parameter is determined by the classical Liouville action on the one-punctured torus or more concretely by the torus classical block evaluated on the saddle point intermediate classical weight. Secondly, as an implication of the aforementioned correspondence it is obtained that the torus accessory parameter is related to the sum of all rescaled column lengths of the so-called “critical” Young diagrams extremizing the instanton “free energy” for the N=2∗ gauge theory. Finally, it is pointed out that thanks to the known relation the sum over the “critical” column lengths can be expressed in terms of a contour integral in which the integrand is built out of certain special functions
Magnetic suspension and balance system advanced study, 1989 design
Boom, Roger W.; Eyssa, Y. M.; Abdelsalam, Moustafa K.; Mcintosh, Glen E.
1991-01-01
The objectives are to experimentally confirm several advanced design concepts on the Magnetic Suspension and Balance Systems (MSBS). The advanced design concepts were identified as potential improvements by Madison Magnetics, Inc. (MMI) during 1984 and 1985 studies of an MSBS utilizing 14 external superconductive coils and a superconductive solenoid in an airplane test model suspended in a wind tunnel. This study confirmed several advanced design concepts on magnetic suspension and balance systems. The 1989 MSBS redesign is based on the results of these experiments. Savings of up to 30 percent in supporting magnet ampere meters and 50 percent in energy stored over the 1985 design were achieved.
Surface Treatment of a Lithium Limiter for Spherical Torus Plasma Experiments
International Nuclear Information System (INIS)
The concept of a flowing lithium first wall for a fusion reactor may lead to a significant advance in reactor design, since it could virtually eliminate the concerns with power density and erosion, tritium retention, and cooling associated with solid walls. As part of investigations to determine the feasibility of this approach, plasma interaction questions in a toroidal plasma geometry are being addressed in the Current Drive eXperiment-Upgrade (CDX-U) spherical torus (ST). The first experiments involved a toroidally local lithium limiter (L3). Measurements of pumpout rates indicated that deuterium pumping was greater for the L3 compared to conventional boron carbide limiters. The difference in the pumpout rates between the two limiter types decreased with plasma exposure, but argon glow discharge cleaning was able to restore the pumping effectiveness of the L3. At no point, however, was the extremely low recycling regime reported in previous lithium experiments achieved. This may be due to the much larger lithium surfaces that were exposed to the plasma in the earlier work. The possibility will be studied in the next set of CDX-U experiments, which are to be conducted with a large area, fully toroidal lithium limiter
Energy Technology Data Exchange (ETDEWEB)
Diez-Jimenez, Efren, E-mail: ediez@ing.uc3m.e [Departamento de Ingenieria Mecanica, Universidad Carlos III de Madrid, Butarque, 15, E28911 Leganes (Spain); Sander, Berit; Timm, Lauri; Perez-Diaz, Jose-Luis [Departamento de Ingenieria Mecanica, Universidad Carlos III de Madrid, Butarque, 15, E28911 Leganes (Spain)
2011-04-15
Research highlights: {yields} A local model is used to demonstrate a flip effect in the orientation of a magnet over a superconductor. {yields} A superconducting torus shape is studied. {yields} Increasing the inner radius of the torus elevates the flip effect point. {yields} There are linear piecewises in the geometrical dependency functions that help to fit the flip effect point. - Abstract: In a previous study, a general local model was used in order to demonstrate the apparition of a flip effect in the equilibrium orientation of a magnet when it is over a superconducting torus. This effect can be easily used in devices such as binary position detectors for magneto-microscopy, contactless sieves or magnetic levels amongst others. We present an initial study useful to design devices based on the flip effect between magnets and torus superconductors. It demonstrates that varying different geometrical parameters the flip effect point can be fixed. Also, it can be observed that increasing the inner radius of the torus elevates the flip effect point. A magneto-mechanical explanation of this phenomenon is exposed. For an increment of cross-section diameter occurs the same behavior. There are linear piecewises in the geometrical dependency functions that can be used for a more accurate fitting of the flip effect point.
International Nuclear Information System (INIS)
Research highlights: → A local model is used to demonstrate a flip effect in the orientation of a magnet over a superconductor. → A superconducting torus shape is studied. → Increasing the inner radius of the torus elevates the flip effect point. → There are linear piecewises in the geometrical dependency functions that help to fit the flip effect point. - Abstract: In a previous study, a general local model was used in order to demonstrate the apparition of a flip effect in the equilibrium orientation of a magnet when it is over a superconducting torus. This effect can be easily used in devices such as binary position detectors for magneto-microscopy, contactless sieves or magnetic levels amongst others. We present an initial study useful to design devices based on the flip effect between magnets and torus superconductors. It demonstrates that varying different geometrical parameters the flip effect point can be fixed. Also, it can be observed that increasing the inner radius of the torus elevates the flip effect point. A magneto-mechanical explanation of this phenomenon is exposed. For an increment of cross-section diameter occurs the same behavior. There are linear piecewises in the geometrical dependency functions that can be used for a more accurate fitting of the flip effect point.
Sunlit Io Atmospheric [O I] 6300 A and the Plasma Torus
Oliversen, Ronald J.; Scherb, Frank; Smyth, William H.; Freed, Melanie E.; Woodward, R. Carey, Jr.; Marcone, Maximus L.; Retherford, Kurt D.; Lupie, Olivia L.; Morgenthaler, Jeffrey P.; Fisher, Richard R. (Technical Monitor)
2001-01-01
A large database of sunlit Io [O I] 6300A emission, acquired over the period 1990-1999, with extensive coverage of Io orbital phase angle phi and System III longitude lambda(sub III), exhibits significant long-term and short-term variations in [O I] 6300A emission intensities. The long-term average intensity shows a clear dependence on lambda(sub III), which establishes conclusively that the emission is produced by the interaction between Io's atmosphere and the plasma torus. Two prominent average intensity maxima, 70 deg to 90 deg wide, are centered at lambda(sub III) about 130deg. and about 295 deg. A comparison of data from October 1998 with a three-dimensional plasma torus model, based upon electron impact excitation of atomic oxygen, suggests a basis for study of the torus interaction with Io's atmosphere. The observed short-term, erratic [O I] 6300A intensity variations fluctuate approximately 20% to 50% on time scale of tens of minutes with less frequent fluctuations of a factor of about 2. The most likely candidate to produce these fluctuations is a time-variable energy flux of field-aligned nonthermal electrons identified recently in Galileo PLS data. If true, the short-term [O I] intensity fluctuations may be related to variable field-aligned currents driven by inward and outward torus plasma transport and/or transient high-latitude, field-aligned potential drops. A correlation between the intensity and emission line width indicates molecular dissociation may contribute significantly to the [O I] 6300A emission. The nonthermal electron energy flux may produce O(1-D) by electron impact dissociation of SO2 and SO, with the excess energy going into excitation of O and its kinetic energy. The [O I] 6300A emission database establishes Io as a valuable probe of the torus, responding to local conditions at Io's position.
Cosmos, an international center for advanced studies
Ryzhov, Iurii; Alifanov, Oleg; Sadin, Stanley; Coleman, Paul
1990-01-01
The concept of Cosmos, a Soviet operating center for aerospace activities, is presented. The main Cosmos participants are the Institute for Aerospace Education, the Institute for Research and Commercial Development, and the Department of Space Policy and Socio-Economic Studies. Cosmos sponsors a number of educational programs, basic research, and studies of the social impact of space-related technologies.
Advances in froth treatment pilot plant studies
Energy Technology Data Exchange (ETDEWEB)
Shelfantook, W.E. [Syncrude Canada Ltd., Edmonton, AB (Canada)
1997-11-01
Bench-scale studies have been performed to find ways to produce diluted bitumen containing less than 1 per cent water. The studies showed that using diluents of high paraffin concentration and elevated solvent ratios could yield very dry diluted bitumen. The laboratory studies led to a series of pilot studies in froth treatment conducted at the facilities of the Canadian Oilsand Network for Research and Development (CONRAD). The pilot studies focused on defining the operating envelope for the Paraffin Froth Treatment Process and establishing the process` response to solvent ratio and temperature. Many different solvent materials were tested to determine their impact on process performance. The work has been part of a development plan for Oilsand leases north of Fort McMurray.
Large N orbifold field theories on the twisted torus
International Nuclear Information System (INIS)
We study the planar equivalence of orbifold field theories on a small three-torus with twisted boundary conditions, generalizing the analysis of [J.L.F. Barbon, C. Hayos, JHEP 0601 (2006) 114, hep-th/0507267]. The non-supersymmetric orbifold models exhibit different large N dynamics from their supersymmetric 'parent' counterparts. In particular, a moduli space of Abelian zero modes is lifted by an O(N2) potential in the 'daughter' theories. We also find disagreement between the number of discrete vacua of both theories, due to fermionic zero modes in the parent theory, as well as the values of semiclassical tunneling contributions to fermionic correlation functions, induced by fractional instantons
Large N orbifold field theories on the twisted torus
Energy Technology Data Exchange (ETDEWEB)
Hoyos, C. [Instituto de Fisica Teorica UAM/CSIC, Facultad de Ciencias, Cantoblanco, 28049 Madrid (Spain)]. E-mail c.hoyos@uam.es
2006-06-05
We study the planar equivalence of orbifold field theories on a small three-torus with twisted boundary conditions, generalizing the analysis of [J.L.F. Barbon, C. Hayos, JHEP 0601 (2006) 114, hep-th/0507267]. The non-supersymmetric orbifold models exhibit different large N dynamics from their supersymmetric 'parent' counterparts. In particular, a moduli space of Abelian zero modes is lifted by an O(N{sup 2}) potential in the 'daughter' theories. We also find disagreement between the number of discrete vacua of both theories, due to fermionic zero modes in the parent theory, as well as the values of semiclassical tunneling contributions to fermionic correlation functions, induced by fractional instantons.
Pygmy resonance and torus mode within Vlasov dynamics
Urban, Michael
2011-01-01
The pygmy dipole resonance in neutron-rich nuclei is studied within the framework of the Vlasov equation which is solved numerically. The interaction used in the Thomas-Fermi ground state and in the Vlasov equation is derived from an energy functional which correctly describes the equation of state of nuclear matter and neutron matter. It is found that the pygmy resonance appears in the electric dipole response of all nuclei with strong neutron excess, the energies and transition probabilities being in reasonable agreement with experimental results. Since the Vlasov equation does not account for any shell effects, this indicates that the existence of the pygmy resonance is a generic phenomenon and does not rely on the specific shell structure. Besides the electric dipole response, the isoscalar torus response is calculated. The transition densities and velocity fields are discussed, too. A comparison of the peak positions and velocity fields suggests that the pygmy resonance can be identified with the mainly ...
Uncertainty quantification of an inflatable/rigidizable torus
Lew, Jiann-Shiun; Horta, Lucas G.; Reaves, Mercedes C.
2006-06-01
There is an increasing interest in lightweight inflatable structures for space missions. The dynamic testing and model updating of these types of structures present many challenges in terms of model uncertainty and structural nonlinearity. This paper presents an experimental study of uncertainty quantification of a 3m-diameter inflatable torus. Model uncertainty can be thought of as coming from two different sources, uncertainty due to changes in controlled conditions, such as temperature and input force level, and uncertainty associated with others random factors, such as measurement noise, etc. To precisely investigate and quantify model uncertainty from different sources, experiments, using sine-sweep excitation in the specified narrow frequency bands, are conducted to collect frequency response function (FRF) under various test conditions. To model the variation of the identified parameters, a singular value decomposition technique is applied to extract the principal components of the parameter change.
Transport and radial electric field in torus plasmas
International Nuclear Information System (INIS)
Transport phenomena in torus plasmas are discussed focusing on the generation of the neoclassical radial electric field. A sophisticated δf Monte Carlo particle simulation code 'FORTEC' is developed including the effect of finite orbit width (FOW), which is the non-local property of the plasma transport. It will be shown that the neoclassical radial electric field in the axisymmetric tokamak is generated due to this FOW effect. The Lagrangian approach is applied to construct a non-local transport theory in the region of near-axis. The reduction of the heat diffusivity toward the axis will be shown. From a statistical point of view, diffusion processes are studied in the presence of irregular magnetic fields. It is shown that the diffusion processes are non-local in almost all the cases if there are some irregularities in the magnetic field. (author)
Advances in phylogenetic studies of Nematoda
Institute of Scientific and Technical Information of China (English)
无
2002-01-01
Nematoda is a metazoan group with extremely high diversity only next to Insecta. Caenorhabditis elegans is now a favorable experimental model animal in modern developmental biology, genetics and genomics studies. However, the phylogeny of Nematoda and the phylogenetic position of the phylum within animal kingdom have long been in debate. Recent molecular phylogenetic studies gave great challenges to the traditional nematode classification. The new phylogenies not only placed the Nematoda in the Ecdysozoan and divided the phylum into five clades, but also provided new insights into animal molecular identification and phylogenetic biodiversity studies. The present paper reviews major progress and remaining problems in the current molecular phylogenetic studies of Nematoda, and prospects the developmental tendencies of this field.
METHODS ADVANCEMENT FOR MILK ANALYSIS: THE MAMA STUDY
The Methods Advancement for Milk Analysis (MAMA) study was designed by US EPA and CDC investigators to provide data to support the technological and study design needs of the proposed National Children=s Study (NCS). The NCS is a multi-Agency-sponsored study, authorized under the...
Advanced Hydraulic Studies on Enhancing Particle Removal
DEFF Research Database (Denmark)
He, Cheng
The removal of suspended solids and attached pollutants is one of the main treatment processes in wastewater treatment. This thesis presents studies on the hydraulic conditions of various particle removal facilities for possible ways to increase their treatment capacity and performance by utilizing...... and improving hydraulic conditions. Unlike most traditional theses which usually focus only on one particular subject of study, this thesis contains four relatively independent studies which cover the following topics: a newly proposed particle settling enhancement plate, the redesign of the inlet zone...... of a high-flow rate clarifier, identify the hydraulic problems of an old partially functioned CSO facility and investigate possible ways to entirely eliminate untreated CSO by improving its hydraulic capacity and performance. In order to be easily understood, each part includes its own abstract...
Advances in clinical study of curcumin.
Yang, Chunfen; Su, Xun; Liu, Anchang; Zhang, Lin; Yu, Aihua; Xi, Yanwei; Zhai, Guangxi
2013-01-01
Curcumin has been estimated as a potential agent for many diseases and attracted great attention owing to its various pharmacological activities, including anti-cancer, and anti-inflammatory. Now curcumin is being applied to a number of patients with breast cancer, rheumatoid arthritis, Alzheimer's disease, colorectal cancer, psoriatic, etc. Several clinical trials have stated that curcumin is safe enough and effective. The objective of this article was to summarize the clinical studies of curcumin, and give a reference for future studies. PMID:23116307
Progress towards high performance plasmas in the National Spherical Torus Experiment (NSTX)
Energy Technology Data Exchange (ETDEWEB)
Kaye, S. M.; Bell, M. G.; Bell, R. E.; Bernabei, S; Bialek, J.; Biewer, T.; Blanchard, W.; Boedo, J.; Bush, C.; Carter, M. D.; Choe, W.; Crocker, N.; Darrow, D. S.; Davis, W.; Delgado-Aparicio, L.; Diem, S.; Ferron, J.; Field, A.; Foley, J.; Fredrickson, E. D.; Gates, D. A.; Gibney, T.; Harvey, R.; Hatcher, R. E.; Heidbrink, W.; Hill, K.; Hosea, J. C.; Jarboe, T. R.; Johnson, D. W.; Kaita, R.; Kessel, C.; Kubota, S.; Kugel, H. W.; Lawson, J.; LeBlanc, B. P.; Lee, K. C.; Levinton, F.; Maingi, R.; Manickam, J.; Maqueda, R.; Marsala, R.; Mastrovito, D.; Mau, T. K.; Medley, S. S.; Menard, J.; Meyer, H.; Mikkelsen, D. R.; Mueller, D.; Munsat, T.; Nelson, B. A.; Neumeyer, C.; Nishino, N.; Ono, M.; Park, H.; Park, W.; Paul, S.; Peebles, T.; Peng, M.; Phillips, C.; Pigarov, A.; Pinsker, R.; Ram, A.; Ramakrishnan, S.; Raman, R.; Rasmussen, D.; Redi, M.; Rensink, M.; Rewoldt, G; Robinson, J.; Roney, P.; Roquemore, A. L.; Ruskov, E; Ryan, P.; Sabbagh, S. A.; Schneider, H.; Skinner, C. H.; Smith, D. R.; Sontag, A.; Soukhanovskii, V.; Stevenson, T.; Stotler, D.; Stratton, B.; Stutman, D.; Swain, D.; Synakowski, E.; Takase, Y.; Taylor, G.; Tritz, K.; Halle, A. von; Wade, M.; White, R.; Wilgen, J.; Williams, M.; Wilson, J. R.; Zhu, W.; Zweben, S. J.; Akers, R.; Beiersdorfer, P.; Betti, R.; Bigelow, T.; Bitter, M.; Bonoli, P.; Bourdelle, C.; Chang, C. S.; Chrzanowski, J.; Domier, C.; Dudek, L.; Efthimion, P. C.; Finkenthal, M.; Fredd, E.; Fu, G. Y.; Glasser, A.; Goldston, R. J.; Greenough, N. L.; Grisham, L. R.; Gorelenkov, N.; Guazzotto, L.; Hawryluk, R. J.; Hogan, J.; Houlberg, W.; Humphreys, D.; Jaeger, F.; Kalish, M.; Krasheninnikov, S.; Lao, L. L.; Lawrence, J.; Leuer, J.; Liu, D.; Luhmann, N. C.; Mazzucato, E.; Oliaro, G.; Pacella, D.; Parsells, R.; Schaffer, M.; Semenov, I.; Shaing, K. C.; Shapiro, M. A.; Shinohara, K.; Sichta, P.; Tang, X.; Vero, R.; Walker, D.; Wampler, W.
2005-10-01
The major objective of the National Spherical Torus Experiment (NSTX) is to understand basic toroidal confinement physics at low aspect ratio and high β_{T} in order to advance the spherical torus (ST) concept. In order to do this, NSTX utilizes up to 7.5 MW of neutral beam injection, up to 6 MW of high harmonic fast waves (HHFWs), and it operates with plasma currents up to 1.5 MA and elongations of up to 2.6 at a toroidal field up to 0.45 T. New facility, and diagnostic and modeling capabilities developed over the past two years have enabled the NSTX research team to make significant progress towards establishing this physics basis for future ST devices. Improvements in plasma control have led to more routine operation at high elongation and high β_{T} (up to ~40%) lasting for many energy confinement times. β_{T} can be limited by either internal or external modes. The installation of an active error field (EF) correction coil pair has expanded the operating regime at low density and has allowed for initial resonant EF amplification experiments. The determination of the confinement and transport properties of NSTX plasmas has benefited greatly from the implementation of higher spatial resolution kinetic diagnostics. The parametric variation of confinement is similar to that at conventional aspect ratio but with values enhanced relative to those determined from conventional aspect ratio scalings and with a β_{T} dependence. The transport is highly dependent on details of both the flow and magnetic shear. Core turbulence was measured for the first time in an ST through correlation reflectometry. Non-inductive start-up has been explored using PF-only and transient co-axial helicity injection techniques, resulting in up to 140 kA of toroidal current generated by the latter technique. Calculated bootstrap and beam-driven currents have sustained up to 60% of the flat-top plasma current in NBI discharges. Studies of HHFW absorption
[Advances in studies on flavonoids of licorice].
Xing, Guo-xiu; Li, Nan; Wang, Tong; Yao, Mei-yan
2003-07-01
The progress in the research of the active ingredients of licorice flavonoid and the pharmacological activities was reviewed. Licorice flavonoid constituents mainly included flavones, flavonals, isoflavones, chalcones, bihydroflavones and bihydrochalcones. Pharmacological investigation concluded that they had antioxidant, antibacterial, antitumer and inhibiting HIV activities. It is important to study further the flavonoid constituents and pharmacological activities. PMID:15139098
Energy Technology Data Exchange (ETDEWEB)
Arbanas, G; Elster, C; Escher, J; Mukhamedzanov, A; Nunes, F; Thompson, I J
2012-02-24
The TORUS collaboration derives its name from the research it focuses on, namely the Theory of Reactions for Unstable iSotopes. It is a Topical Collaboration in Nuclear Theory, and funded by the Nuclear Theory Division of the Office of Nuclear Physics in the Office of Science of the Department of Energy. The funding supports one postdoctoral researcher for the years 1 through 3. The collaboration brings together as Principal Investigators a large fraction of the nuclear reaction theorists currently active within the USA. The mission of the TORUS Topical Collaboration is to develop new methods that will advance nuclear reaction theory for unstable isotopes by using three-body techniques to improve direct-reaction calculations, and, by using a new partial-fusion theory, to integrate descriptions of direct and compound-nucleus reactions. This multi-institution collaborative effort is directly relevant to three areas of interest: the properties of nuclei far from stability; microscopic studies of nuclear input parameters for astrophysics, and microscopic nuclear reaction theory.
Advanced microwave radiometer antenna system study
Kummer, W. H.; Villeneuve, A. T.; Seaton, A. F.
1976-01-01
The practicability of a multi-frequency antenna for spaceborne microwave radiometers was considered in detail. The program consisted of a comparative study of various antenna systems, both mechanically and electronically scanned, in relation to specified design goals and desired system performance. The study involved several distinct tasks: definition of candidate antennas that are lightweight and that, at the specified frequencies of 5, 10, 18, 22, and 36 GHz, can provide conical scanning, dual linear polarization, and simultaneous multiple frequency operation; examination of various feed systems and phase-shifting techniques; detailed analysis of several key performance parameters such as beam efficiency, sidelobe level, and antenna beam footprint size; and conception of an antenna/feed system that could meet the design goals. Candidate antennas examined include phased arrays, lenses, and optical reflector systems. Mechanical, electrical, and performance characteristics of the various systems were tabulated for ease of comparison.
Advanced NSTS propulsion system verification study
Wood, Charles
1989-01-01
The merits of propulsion system development testing are discussed. The existing data base of technical reports and specialists is utilized in this investigation. The study encompassed a review of all available test reports of propulsion system development testing for the Saturn stages, the Titan stages, and the Space Shuttle main propulsion system. The knowledge on propulsion system development and system testing available from specialists and managers was also 'tapped' for inclusion.
Advances from neuroimaging studies in eating disorders
Frank, Guido K.W.
2016-01-01
Over the past decade brain imaging has helped better define eating disorder related brain circuitry. Brain research on gray and white matter volumes had been inconsistent, possibly due to the effects of acute starvation, exercise, medication and comorbidity, but newer studies controlled for such effects. Those studies suggest larger left medial orbitofrontal gyrus rectus volume in ill adult and adolescent anorexia nervosa after recovery from anorexia nervosa, and in adult bulimia nervosa. The orbitofrontal cortex is important in terminating food intake and altered function could contribute to self-starvation. The right insula, which processes taste but also interoception, was enlarged in ill adult and adolescent anorexia nervosa, as well as adults recovered from the illness. The fixed perception of being fat in anorexia nervosa could be related to altered insula function. A few studies investigated WM integrity, with the most consistent finding of reduced fornix integrity in anorexia and bulimia nervosa, a limbic pathway important in emotion but also food intake regulation. Functional brain imaging using basic sweet taste stimuli in eating disorders during the ill state or after recovery implicated repeatedly reward pathways, including insula and striatum. Brain imaging that targeted dopamine related brain activity using taste-reward conditioning tasks suggested that this circuitry is hypersensitive in anorexia nervosa, but hypo-responsive in bulimia nervosa and obesity. Those results are in line with basic research and suggest adaptive reward system changes in the human brain in response to extremes of food intake, changes that could interfere with normalization of eating behavior. PMID:25902917
Advances from neuroimaging studies in eating disorders.
Frank, Guido K W
2015-08-01
Over the past decade, brain imaging has helped to better define eating disorder-related brain circuitry. Brain research on gray matter (GM) and white matter (WM) volumes had been inconsistent, possibly due to the effects of acute starvation, exercise, medication, and comorbidity, but newer studies have controlled for such effects. Those studies suggest larger left medial orbitofrontal gyrus rectus volume in ill adult and adolescent anorexia nervosa after recovery from anorexia nervosa, and in adult bulimia nervosa. The orbitofrontal cortex is important in terminating food intake, and altered function could contribute to self-starvation. The right insula, which processes taste but also interoception, was enlarged in ill adult and adolescent anorexia nervosa, as well as adults recovered from the illness. The fixed perception of being fat in anorexia nervosa could be related to altered insula function. A few studies investigated WM integrity, with the most consistent finding of reduced fornix integrity in anorexia and bulimia nervosa-a limbic pathway that is important in emotion but also food intake regulation. Functional brain imaging using basic sweet taste stimuli in eating disorders during the ill state or after recovery implicated repeatedly reward pathways, including insula and striatum. Brain imaging that targeted dopamine-related brain activity using taste-reward conditioning tasks suggested that this circuitry is hypersensitive in anorexia nervosa, but hyporesponsive in bulimia nervosa and obesity. Those results are in line with basic research and suggest adaptive reward system changes in the human brain in response to extremes of food intake-changes that could interfere with normalization of eating behavior. PMID:25902917
Advanced studies on human gene ZNF322
Institute of Scientific and Technical Information of China (English)
LI Yongqing; WANG Yuequn; YUAN Wuzhou; DENG Yun; ZHU Chuanbing; WU Xiushan
2007-01-01
The human novel gene of ZNF322 is cloned from human fetal eDNA library using the primers on the basis of the ZNF322 sequence analyzed with computer.The gene is located on Chromosome 6p22.1,and encodes a protein consisting of 402 amino acid residues and containing nine tandem C2H2-type zinc-finger motifs.Northern blot result shows that the gene is expressed in all examined adult tissues.Subcellular location study indicates that ZNF322-EGFP fusion protein is distributed in the nucleus and cytoplasm.Reporter gene assays show that ZNF322 is a potential transcriptional activator.
Topology of holomorphic Lefschetz pencils on the four-torus
Hamada, Noriyuki; Hayano, Kenta
2016-01-01
In this paper we discuss topological properties of holomorphic Lefschetz pencils on the four-torus. Relying on the theory of moduli spaces of polarized abelian surfaces, we first prove that, under some mild assumption, the (smooth) isomorphism class of a holomorphic Lefschetz pencil on the four-torus is uniquely determined by its genus and divisibility. We then explicitly give a system of vanishing cycles of the genus-3 holomorphic Lefschetz pencil on the four-torus due to Smith, and obtain t...
ITER - torus vacuum pumping system remote handling issues
International Nuclear Information System (INIS)
This report describes design issues concerning remote maintenance of the ITER torus vacuum pumping system. The key issues under investigation are the valve seal exchange concept under inert gas and an alternative on-line vacuum option; flask handling support methods; flask handling/pump cell access interfacing; and valve seal inspection feasibility. The horizontal exchange of moving parts (seals/disc) for a 1.5 m regeneration isolation gate valve appears technically feasible. However, it is recommended that other commercially available valves that are lighter and narrower be examined with a view to reducing the overall size of the flask and simplifying maintenance tasks. A variant of this scheme appears feasible where the seals are replaced while the torus is under vacuum using two slit valves within the body of the main valve. This approach offers reduced cost, minimized remote handling requirements, and possibly increased plant availability. Remote handling of the flask and valve moving parts by overhead support methods is studied analytically. The forces and moments acting on the flask and resulting deflections during seal exchange operations show that a more rigid support of the flask is required than can be supplied using a crane. An alternative floor-mounted support method is proposed. Pump cell access is developed from the standpoint of the handling and transfer of a seal exchange flask as well as other pump room components. A tool for in-situ inspection of regeneration-isolation valve seats appears feasible. The concept could be developed for vacuum use as well as for in-situ repair of the seats. (21 figs.)
Torus CLAS12-Superconducting Magnet Quench Analysis
Energy Technology Data Exchange (ETDEWEB)
Kashikhin, V. S. [Fermilab; Elouadhiri, L. [Jefferson Lab; Ghoshal, P. K. [Jefferson Lab; Kashy, D. [Jefferson Lab; Makarov, A. [Fermilab; Pastor, O. [Jefferson Lab; Quettier, L. [Jefferson Lab; Velev, G. [Fermilab; Wiseman, M. [Jefferson Lab
2014-01-01
The JLAB Torus magnet system consists of six superconducting trapezoidal racetrack-type coils assembled in a toroidal configuration. These coils are wound with SSC-36 Nb-Ti superconductor and have the peak magnetic field of 3.6 T. The first coil manufacturing based on the JLAB design began at FNAL. The large magnet system dimensions (8 m diameter and 14 MJ of stored energy) dictate the need for quench protection. Each coil is placed in an aluminum case mounted inside a cryostat and cooled by 4.6 K supercritical helium gas flowing through a copper tube attached to the coil ID. The large coil dimensions and small cryostat thickness drove the design to challenging technical solutions, suggesting that Lorentz forces due to transport currents and eddy currents during quench and various failure scenarios are analyzed. The paper covers the magnet system quench analysis using the OPERA3d Quench code.
On the Torus Cobordant Cohomology Spheres
Indian Academy of Sciences (India)
Ali Özkurt; Doğan Dönmez
2009-02-01
Let be a compact Lie group. In 1960, P A Smith asked the following question: ``Is it true that for any smooth action of on a homotopy sphere with exactly two fixed points, the tangent -modules at these two points are isomorphic?" A result due to Atiyah and Bott proves that the answer is `yes’ for $\\mathbb{Z}_p$ and it is also known to be the same for connected Lie groups. In this work, we prove that two linear torus actions on $S^n$ which are -cobordant (cobordism in which inclusion of each boundary component induces isomorphisms in $\\mathbb{Z}$-cohomology) must be linearly equivalent. As a corollary, for connected case, we prove a variant of Smith’s question.
An FPGA-based torus communication network
Energy Technology Data Exchange (ETDEWEB)
Pivanti, Marcello; Schifano, Sebastiano Fabio [INFN, Ferrara (Italy); Ferrara Univ. (Italy); Simma, Hubert [DESY, Zeuthen (Germany). John von Neumann-Institut fuer Computing NIC
2011-02-15
We describe the design and FPGA implementation of a 3D torus network (TNW) to provide nearest-neighbor communications between commodity multi-core processors. The aim of this project is to build up tightly interconnected and scalable parallel systems for scientific computing. The design includes the VHDL code to implement on latest FPGA devices a network processor, which can be accessed by the CPU through a PCIe interface and which controls the external PHYs of the physical links. Moreover, a Linux driver and a library implementing custom communication APIs are provided. The TNW has been successfully integrated in two recent parallel machine projects, QPACE and AuroraScience. We describe some details of the porting of the TNW for the AuroraScience system and report performance results. (orig.)
Asymmetries in the Io plasma torus
Desch, M. D.; Farrell, W. M.; Kaiser, M. L.
1994-01-01
Using Ulysses radio wave data taken during the 1992 Jupiter encounter, we conclude that there are significant large and small spatial scale azimuthal asymmetries at high latitudes in the Io plasma torus. During a period of time near perijove when the spacecraft motion was predominantly in the azimuthal direction and was relatively fixed in both latitude and radial distance, inferred electron densities depart significantly from the common assumption of longitudinal symmetry. Specifically, electron plasma concentrations near 0 deg system III longitude (and 0400 LT) are greater than those near 180 deg (and 0000 LT). Superposed on this large-scale variation are regularly spaced density depletions, 30-50% in magnitude, and having a spatial periodicity of about 17 deg. Some of these depletions may drive various known radio and plasma wave sources by means of large B parallel electric potentials. The observations are compared with recent models and with the in-situ Voyager observations.
An FPGA-based torus communication network
International Nuclear Information System (INIS)
We describe the design and FPGA implementation of a 3D torus network (TNW) to provide nearest-neighbor communications between commodity multi-core processors. The aim of this project is to build up tightly interconnected and scalable parallel systems for scientific computing. The design includes the VHDL code to implement on latest FPGA devices a network processor, which can be accessed by the CPU through a PCIe interface and which controls the external PHYs of the physical links. Moreover, a Linux driver and a library implementing custom communication APIs are provided. The TNW has been successfully integrated in two recent parallel machine projects, QPACE and AuroraScience. We describe some details of the porting of the TNW for the AuroraScience system and report performance results. (orig.)
Recent Advances in the Studies on Luotonins
Directory of Open Access Journals (Sweden)
Yurngdong Jahng
2011-06-01
Full Text Available Luotonins are alkaloids from the aerial parts of Peganum nigellastrum Bunge. that display three major skeleton types. Luotonins A, B, and E are pyrroloquinazolino-quinoline alkaloids, luotonins C and D are canthin-6-one alkaloids, and luotonin F is a 4(3H-quinazolinone alkaloid. All six luotonins have shown promising cytotoxicities towards selected human cancer cell lines, especially against leukemia P-388 cells. Luotonin A is the most active one, with its activity stemming from topoisomerase I-dependent DNA-cleavage. Such intriguing biological activities and unique structures have led not only to the development of synthetic methods for the efficient synthesis of these compounds, but also to interest in structural modifications for improving the biological properties. Recent progress in the study of luotonins is covered.
Aerodynamic optimization studies on advanced architecture computers
Chawla, Kalpana
1995-01-01
The approach to carrying out multi-discipline aerospace design studies in the future, especially in massively parallel computing environments, comprises of choosing (1) suitable solvers to compute solutions to equations characterizing a discipline, and (2) efficient optimization methods. In addition, for aerodynamic optimization problems, (3) smart methodologies must be selected to modify the surface shape. In this research effort, a 'direct' optimization method is implemented on the Cray C-90 to improve aerodynamic design. It is coupled with an existing implicit Navier-Stokes solver, OVERFLOW, to compute flow solutions. The optimization method is chosen such that it can accomodate multi-discipline optimization in future computations. In the work , however, only single discipline aerodynamic optimization will be included.
Advances in pharmacological studies of silymarin
Directory of Open Access Journals (Sweden)
Yao-Cheng Rui
1991-01-01
Full Text Available Silymarin is the flavonoids extracted from the seeds of Silybum marianum (L Gearth as a mixture of three structural isomers: silybin, silydianin and silychristin, the former being the most active component. Silymarin protects liver cell membrane against hepatotoxic agents and improves liver function in experimental animals and humans. It is generally accepted that silymarin exerts a membrane-stabilizing action preventing or inhibiting membrane peroxidation. The experiments with soybean lipoxygenase showed that the three components of silymarin brought about a concentration-dependent non-competitive inhibition of the lipoxygenase. The experiments also showed an analogous interaction with animal lipoxygenase, thus showing that an inhibition of the peroxidation of the fatty acid in vivo was self-evident. Silybin almost completely suppressed the formation of PG at the highest concentration (0.3 mM and proved to be an inhibitor of PG synthesis in vitro. In our experiments, silybin at lower dose (65 mg/Kg decreased liver lipoperoxide content and microsomal lipoperoxidation to 84.5% and 68.55% of those of the scalded control rats respectively, and prevented the decrease of liver microsomal cytochrome p-450 content and p-nitroanisole-0-demethylase activity 24 h post-scalding. Effects of silymarin on cardiovascular systen have been studied in this university since 1980. O. O silymarin 800 mg/Kg/d or silybin 600 mg/Kg/d reduced plasma total cholesterol, LDL-C and VLDL-C. They however, enhanced HDL-C in hyperlipenic rats. Further studies showed that silymarin enhanced HDL-C in hyperlipemic rats. Further studies showed that silymarin enhanced HDL-C but didn't affect HDL-C, a property of this component which is beneficial to treatment of atherosclerosis. The results showed silymarin 80 mg or silybin 60 mg decreased in vitro platelet aggregation (porcentagem in rats. The maximal platelet aggregation induced by ADP declined significantly, and time to reach
Study and Implementation of Advanced Neuroergonomic Techniques
Directory of Open Access Journals (Sweden)
B.F.Momin
2012-08-01
Full Text Available Research in the area of neuroergonomics has blossomed in recent years with the emergence of noninvasive techniques for monitoring human brain function that can be used to study various aspects of human behavior in relation to technology and work, including mental workload, visual attention, working memory, motor control, human-automation interaction, and adaptive automation. Consequently, this interdisciplinary field is concerned with investigations of the neural bases of human perception,cognition, and performance in relation to systems and technologies in the real world -- for example, in the use of computers and various other machines at home or in the workplace, and in operating vehiclessuch as aircraft, cars, trains, and ships. We will look at recent trends in functional magnetic resonance imaging (fMRI, with a special focus on the questions that have been addressed. This focus is particularly important for functional neuroimaging, whose contributions will be measured by the depth of the questions asked. The ever-increasing understanding of the brain and behavior at work in the real world, the development of theoretical underpinnings, and the relentless spread of facilitative technology in the West and abroad are inexorably broadening the substrates for this interdisciplinary area of research and practice. Neuroergonomics blends neuroscience and ergonomics to the mutual benefit of both fields, and extends the study of brain structure and function beyond the contrived laboratory settings often used in neuropsychological, psychophysical, cognitive science, and other neurosciencerelated fields. Neuroergonomics is providing rich observations of the brain and behavior at work, at home, in transportation, and in other everyday environments in human operators who see, hear, feel, attend, remember, decide, plan, act, move, or manipulate objects among other people and technology in diverse,real-world settings. The neuroergonomics approach is
ATF [Advanced Toroidal Facility]-2 studies
International Nuclear Information System (INIS)
Design studies for a low-aspect-ratio, large next-generation stellarator, ATF-II, with high-current-density, high-field, stable NbTi/Cu helical windings are described. The design parameters are an average plasma radius of 0.52 m, a major radius of 2 m, and a field on axis of 4-5 T, with 10 to 15 MW of heating power. Such a device would be comparable in scope to other next-generation stellarators but would have roughly the same aspect ratio as the tokamaks without, however, the need for current drive to sustain steady-state operation. A number of low-aspect-ratio physics issues need to be addressed in the design of ATF-II, primarily compromises between high-beta capability and good confinement properties. A six-field-period Compact Torsatron is chosen as a reference design for ATF-II, and its main features and performance predictions are discussed. An integrated (beta capability and confinement) optimization approach and optimization of superconducting windings are also discussed. 36 refs., 13 figs., 2 tabs
A Study on Performance Requirements for Advanced Alarm System
International Nuclear Information System (INIS)
A design goals of advanced alarm system is providing advanced alarm information to operator in main control room. To achive this, we applied computer based system to Alarm System. Because, It should apply data management and advanced alarm processing(ie. Data Base Mangegment System and S/W module for alarm processing). These are not impossible in analog based alarm system. And, preexitance research examples are made on digital computer. We have digital systems for test of advanced alarm system table and have tested and studied using by test equipment in the view point of the system performance, stability and security. In this paper, we discribed about general software architecture of preexitance research examples. Also, CPU performance and requirements of system software that served to accommodate it, stability and security
Neoadjuvant chemotherapy in advanced epithelial ovarian cancer: A survival study
Directory of Open Access Journals (Sweden)
Upasana Baruah
2015-01-01
Full Text Available Context: Patients with advanced ovarian cancer have a poor prognosis in spite of the best possible care. Primary debulking surgery has been the standard of care in advanced ovarian cancer; however, it is associated with high mortality and morbidity rates as shown in various studies. Several studies have discussed the benefit of neoadjuvant chemotherapy in patients with advanced ovarian cancer. Aims: This study aims to evaluate the survival statistics of the patients who have been managed with interval debulking surgery (IDS from January 2007 to December 2009. Materials and Methods: During the period from January 2007 to December 2009, a retrospective analysis of 104 patients who underwent IDS for stage IIIC or IV advanced epithelial ovarian cancer at our institute were selected for the study. IDS was attempted after three to five courses of chemotherapy with paclitaxal (175 mg/m 2 and carboplatin (5-6 of area under curve. Overall survival (OS and progression free survival (PFS were compared with results of primary debulking study from existing literature. OS and PFS rates were estimated by means of the Kaplan-Meier method. Results were statistically analyzed by IBM SPSS Statistics 19. Results: The median OS was 26 months and the median PFS was 18 months. In multivariate analysis it was found that both OS and PFS was affected by the stage, and extent of debulking. Conclusions: Neoadjuvant chemotherapy, followed by surgical cytoreduction is a promising treatment strategy for the management of advanced epithelial ovarian cancers.
Advancing the Theory of Nuclear Reactions with Rare Isotopes. From the Laboratory to the Cosmos
Energy Technology Data Exchange (ETDEWEB)
Nunes, Filomena [Michigan State Univ., East Lansing, MI (United States)
2015-06-01
The mission of the Topical Collaboration on the Theory of Reactions for Unstable iSotopes (TORUS) was to develop new methods to advance nuclear reaction theory for unstable isotopes—particularly the (d,p) reaction in which a deuteron, composed of a proton and a neutron, transfers its neutron to an unstable nucleus. After benchmarking the state-of-the-art theories, the TORUS collaboration found that there were no exact methods to study (d,p) reactions involving heavy targets; the difficulty arising from the long-range nature of the well known, yet subtle, Coulomb force. To overcome this challenge, the TORUS collaboration developed a new theory where the complexity of treating the long-range Coulomb interaction is shifted to the calculation of so-called form-factors. An efficient implementation for the computation of these form factors was a major achievement of the TORUS collaboration. All the new machinery developed are essential ingredients to analyse (d,p) reactions involving heavy nuclei relevant for astrophysics, energy production, and stockpile stewardship.
Staining of palatal torus secondary to long term minocycline therapy
Directory of Open Access Journals (Sweden)
Buddula Aravind
2009-01-01
Full Text Available Minocycline and other tetracycline analogs are well known to cause discoloring of alveolar bone, teeth and other tissues. The present case reports palatine torus discoloring, in a 91-year-old patient, after long term minocycline therapy. The patient was presented with staining of the palatal torus resulting from prior minocycline use for three-and-a-half years. The diagnosis of minocycline staining of palatal torus was done during a routine hygiene examination. The patient was informed that the bluish appearance of the palatal torus was the result of long term minocycline use. The patient was not willing to discontinue the antibiotic and was not concerned about the appearance. The clinician should inform patients on long term minocycline therapy about the possible side effects of staining of the alveolar bone, teeth and other soft tissue.
Topological T-duality for torus bundles with monodromy
Baraglia, David
2015-05-01
We give a simplified definition of topological T-duality that applies to arbitrary torus bundles. The new definition does not involve Chern classes or spectral sequences, only gerbes and morphisms between them. All the familiar topological conditions for T-duals are shown to follow. We determine necessary and sufficient conditions for existence of a T-dual in the case of affine torus bundles. This is general enough to include all principal torus bundles as well as torus bundles with arbitrary monodromy representations. We show that isomorphisms in twisted cohomology, twisted K-theory and of Courant algebroids persist in this general setting. We also give an example where twisted K-theory groups can be computed by iterating T-duality.
On Spin Structures and Dirac Operators on the Noncommutative Torus
Paschke, Mario; Sitarz, Andrzej
2006-01-01
We find and classify possible equivariant spin structures with Dirac operators on the noncommutative torus, proving that similarly as in the classical case the spectrum of the Dirac operator depends on the spin structure.
Repellin, Cécile; Neupert, Titus; Bernevig, B. Andrei; Regnault, Nicolas
2015-09-01
Multilayer fractional quantum Hall wave functions can be used to construct the non-Abelian states of the Zk Read-Rezayi series upon symmetrization over the layer index. Unfortunately, this construction does not yield the complete set of Zk ground states on the torus. We develop an alternative projective construction of Zk Read-Rezayi states that complements the existing one. On the multilayer torus geometry, our construction consists of introducing twisted boundary conditions connecting the layers before performing the symmetrization. We give a comprehensive account of this construction for bosonic states, and numerically show that the full ground state and quasihole manifolds are recovered for all computationally accessible system sizes. Furthermore, we analyze the neutral excitation modes above the Moore-Read on the torus through an extensive exact diagonalization study. We show numerically that our construction can be used to obtain excellent approximations to these modes. Finally, we extend our symmetrization scheme to the plane and sphere geometries.
Dust in the Torus of the AGN Unified Model
Mason, Rachel E
2014-01-01
These proceedings are based on an invited review talk at the 7th Meeting on Cosmic Dust. The scope of the meeting was broad, covering dust-related topics in areas from comets to debris disks and high-redshift galaxies. This is therefore intended to be an accessible, introductory overview of the dusty torus of the AGN unified model, aimed at summarizing our current understanding of the torus and with some emphasis on the solid-state spectral features observed.
Torus as phase space: Weyl quantization, dequantization and Wigner formalism
Ligabò, Marilena
2014-01-01
The Weyl quantization of classical observables on the torus (as phase space) without regularity assumptions is explicitly computed. The equivalence class of symbols yielding the same Weyl operator is characterized. The Heisenberg equation for the dynamics of general quantum observables is written through the Moyal brackets on the torus and the support of the Wigner transform is characterized. Finally, a dequantization procedure is introduced that applies, for instance, to the Pauli matrices. ...
Existence of Exotic Torus Isomer States and Their Precession Motions
Ichikawa, Takatoshi; Matsuyanagi, Kenichi; Maruhn, Joachim A.; Itagaki, Naoyuki
We systematically investigate the existence of exotic high-spin torus isomers and their precession motions for a series of N = Z even-even nuclei from 28Si to 56Ni. For this purpose, we use the cranked three-dimensional Hatree-Fock (HF) method in a systematic search for high-spin torus isomers and the three-dimensional time-dependent Hatree-Fock (TDHF) method for describing the precession motion of the torus isomer. We obtain high-spin torus isomers in 36Ar, 40Ca, 44Ti, 48Cr, and 52Fe. The emergence of the torus isomers is associated with the alignments of single-particle angular momenta, which is the same mechanism as found in 40Ca. We find that all the obtained torus isomers execute the precession motion at least two rotational periods. The moment of inertia about a perpendicular axis, which characterizes the precession motion, is found to be close to the classical rigid-body value.
Proposal for FRX-C and multiple-cell Compact Torus experiments
Energy Technology Data Exchange (ETDEWEB)
Dreicer, H.
1979-10-01
A Compact Torus (CT) is a configuration for plasma confinement that offers possible engineering advantages for fusion power generation such as small size, simple blanket geometry, natural divertor, and spatially separable functions of plasma production and fusion energy generation. Two experiments to study the physics and technology of some particular CT configurations are proposed here as part of the LASL Compact Torus Program Plan. One experiment, FRX-C, is designed to study CT stability and transport properties by scaling the parameters of the existing FRX-B field-reversed theta-pinch experiment to higher temperatures, larger size, and increased plasma lifetime. The second experiment, a modification of the existing Scylla IV-P device, would form a linear array of CTs with the aim of understanding the effect on CT transport of improved plasma confinement on the open field lines outside the separatrix, as well as other multiple-cell effects.
Lagrange multiplier and Wess-Zumino variable as large extra dimensions in the torus universe
Nejad, Salman Abarghouei; Monemzadeh, Majid
2015-01-01
We study the effect of the topology of universe by gauging the non-relativistic particle model on the torus and 3-torus, using the symplectic formalism of constrained systems and embedding those models on extended phase-spaces. Also, we obtain the generators of the gauge transformations for gauged models. Extracting the corresponding Poisson structure of the existed constraints, we show the effect of the topology on the canonical structure of the phase-spaces of those models and suggest some phenomenology to prove the topology of the universe and probable non-commutative structure of the space. In addition, we show that the number of large extra dimensions in the Phase-spaces of the gauged embeded models are exactly two. Moreover, in the classical form, we talk over MOND theory in order to study the origin of the terms appeared in the gauged theory, which modify the Newton's second law.
THE LACK OF TORUS EMISSION FROM BL LACERTAE OBJECTS: AN INFRARED VIEW OF UNIFICATION WITH WISE
International Nuclear Information System (INIS)
We use data from the Wide-Field Infrared Survey Explorer (WISE) to perform a statistical study on the mid-infrared (IR) properties of a large number (∼102) of BL Lac objects—low-luminosity active galactic nuclei (AGNs) with a jet beamed toward the Earth. As expected, many BL Lac objects are so highly beamed that their jet synchrotron emission dominates their IR spectral energy distributions. In other BL Lac objects, however, the jet is not strong enough to completely dilute the rest of the AGN emission. We do not see observational signatures of the dusty torus from these weakly beamed BL Lac objects. The lack of observable torus emission is consistent with suggestions that BL Lac objects are fed by radiatively inefficient accretion disks. Implications for the 'nature versus nurture' debate for FR I and FR II radio galaxies are briefly discussed. Our study supports the notion that, beyond orientation, accretion rate plays an important role in AGN unification.
Proposal for FRX-C and multiple-cell Compact Torus experiments
International Nuclear Information System (INIS)
A Compact Torus (CT) is a configuration for plasma confinement that offers possible engineering advantages for fusion power generation such as small size, simple blanket geometry, natural divertor, and spatially separable functions of plasma production and fusion energy generation. Two experiments to study the physics and technology of some particular CT configurations are proposed here as part of the LASL Compact Torus Program Plan. One experiment, FRX-C, is designed to study CT stability and transport properties by scaling the parameters of the existing FRX-B field-reversed theta-pinch experiment to higher temperatures, larger size, and increased plasma lifetime. The second experiment, a modification of the existing Scylla IV-P device, would form a linear array of CTs with the aim of understanding the effect on CT transport of improved plasma confinement on the open field lines outside the separatrix, as well as other multiple-cell effects
Stability of small-amplitude torus knot solutions of the localized induction approximation
International Nuclear Information System (INIS)
We study the linear stability of small-amplitude torus knot solutions of the localized induction approximation equation for the motion of a thin vortex filament in an ideal fluid. Such solutions can be constructed analytically through the connection with the focusing nonlinear Schroedinger equation using the method of isoperiodic deformations. We show that these (p, q) torus knots are generically linearly unstable for p q, in contrast with an earlier linear stability study by Ricca (1993 Chaos 3 83-95; 1995 Chaos 5 346; 1995 Small-scale Structures in Three-dimensional Hydro and Magneto-dynamics Turbulence (Lecture Notes in Physics vol 462) (Berlin: Springer)). We also provide an interpretation of the original perturbative calculation in Ricca (1995), and an explanation of the numerical experiments performed by Ricca et al (1999 J. Fluid Mech. 391 29-44), in light of our results.
Advanced stratified charge rotary aircraft engine design study
Badgley, P.; Berkowitz, M.; Jones, C.; Myers, D.; Norwood, E.; Pratt, W. B.; Ellis, D. R.; Huggins, G.; Mueller, A.; Hembrey, J. H.
1982-01-01
A technology base of new developments which offered potential benefits to a general aviation engine was compiled and ranked. Using design approaches selected from the ranked list, conceptual design studies were performed of an advanced and a highly advanced engine sized to provide 186/250 shaft Kw/HP under cruise conditions at 7620/25,000 m/ft altitude. These are turbocharged, direct-injected stratified charge engines intended for commercial introduction in the early 1990's. The engine descriptive data includes tables, curves, and drawings depicting configuration, performance, weights and sizes, heat rejection, ignition and fuel injection system descriptions, maintenance requirements, and scaling data for varying power. An engine-airframe integration study of the resulting engines in advanced airframes was performed on a comparative basis with current production type engines. The results show airplane performance, costs, noise & installation factors. The rotary-engined airplanes display substantial improvements over the baseline, including 30 to 35% lower fuel usage.
Advanced dementia research in the nursing home: the CASCADE study.
Mitchell, Susan L; Kiely, Dan K; Jones, Richard N; Prigerson, Holly; Volicer, Ladislav; Teno, Joan M
2006-01-01
Despite the growing number of persons with advanced dementia, and the need to improve their end-of-life care, few studies have addressed this important topic. The objectives of this report are to present the methodology established in the CASCADE (Choices, Attitudes, and Strategies for Care of Advanced Dementia at the End-of-Life) study, and to describe how challenges specific to this research were met. The CASCADE study is an ongoing, federally funded, 5-year prospective cohort study of nursing [nursing home (NH)] residents with advanced dementia and their health care proxies (HCPs) initiated in February 2003. Subjects were recruited from 15 facilities around Boston. The recruitment and data collection protocols are described. The demographic features, ownership, staffing, and quality of care of participant facilities are presented and compared to NHs nationwide. To date, 189 resident/HCP dyads have been enrolled. Baseline data are presented, demonstrating the success of the protocol in recruiting and repeatedly assessing NH residents with advanced dementia and their HCPs. Factors challenging and enabling implementation of the protocol are described. The CASCADE experience establishes the feasibility of conducting rigorous, multisite dementia NH research, and the described methodology serves as a detailed reference for subsequent CASCADE publications as results from the study emerge. PMID:16917187
[Advances in Genomics Studies for Coronary Artery Disease].
Wang, Ying; Zhu, Hui-juan; Zeng, Yong
2015-08-01
Coronary artery disease (CAD) is one of the major life-threatening diseases. In addition to traditional risk factors including age, sex, smoking, hypertension,and diabetes, genomic studies have shown that CAD has obvious genetic predisposition. In recent years, the rapid advances in genomics shed new light on early diagnosis, risk stratification and new treatment targets. PMID:26564468
Design study on advanced reprocessing systems for FR fuel cycle
Energy Technology Data Exchange (ETDEWEB)
Tanaka, H.; Kawamura, F.; Nishimura, T.; Kamiya, M. [Japan Nuclear Cycle Development Institute, Ibaraki (Japan)
2001-07-01
A design study has been carried out for four advanced reprocessing technologies for the future fast rector (FR) recycle systems (advanced aqueous, and three non-aqueous systems based on oxide electrowinning, metal electrorefining, and fluoride volatility methods). The systems were evaluated mainly from the viewpoint of economics. It has been shown that, for MOX fuel reprocessing, all the systems with a capacity of 200 t/y attains the economical target, whereas for such a small capacity as 50 t/y, only the non-aqueous systems have potential to attain the target. For metallic and nitride fuel, a metal electrorefining system has been shown to be advantageous. (author)
From "fixing women" to "institutional transformation": An ADVANCE case study
Yennello, Sherry; Kaunas, Christine
2015-12-01
The United States' position in the global economy requires an influx of women into science, technology, engineering, and mathematics (STEM) fields in order to remain competitive. Despite this, the representation of women in STEM continues to be low. The National Science Foundation's ADVANCE Program addresses this issue by funding projects that aim to increase the representation of women in academic STEM fields through transformation of institutional structures that impede women's progress in academic STEM fields. This paper includes a case study of the Texas A&M University ADVANCE Program.
Design study on advanced reprocessing systems for FR fuel cycle
International Nuclear Information System (INIS)
A design study has been carried out for four advanced reprocessing technologies for the future fast rector (FR) recycle systems (advanced aqueous, and three non-aqueous systems based on oxide electrowinning, metal electrorefining, and fluoride volatility methods). The systems were evaluated mainly from the viewpoint of economics. It has been shown that, for MOX fuel reprocessing, all the systems with a capacity of 200 t/y attains the economical target, whereas for such a small capacity as 50 t/y, only the non-aqueous systems have potential to attain the target. For metallic and nitride fuel, a metal electrorefining system has been shown to be advantageous. (author)
Methods for studying fuel management in advanced gas cooled reactors
International Nuclear Information System (INIS)
The methods used for studying fuel and absorber management problems in AGRs are described. The basis of the method is the use of ARGOSY lattice data in reactor calculations performed at successive time steps. These reactor calculations may be quite crude but for advanced design calculations a detailed channel-by-channel representation of the whole core is required. The main emphasis of the paper is in describing such an advanced approach - the ODYSSEUS-6 code. This code evaluates reactor power distributions as a function of time and uses the information to select refuelling moves and determine controller positions. (author)
Magnetized plasma flow injection into tokamak and high-beta compact torus plasmas
Matsunaga, Hiroyuki; Komoriya, Yuuki; Tazawa, Hiroyasu; Asai, Tomohiko; Takahashi, Tsutomu; Steinhauer, Loren; Itagaki, Hirotomo; Onchi, Takumi; Hirose, Akira
2010-11-01
As an application of a magnetized coaxial plasma gun (MCPG), magnetic helicity injection via injection of a highly elongated compact torus (magnetized plasma flow: MPF) has been conducted on both tokamak and field-reversed configuration (FRC) plasmas. The injected plasmoid has significant amounts of helicity and particle contents and has been proposed as a fueling and a current drive method for various torus systems. In the FRC, MPF is expected to generate partially spherical tokamak like FRC equilibrium by injecting a significant amount of magnetic helicity. As a circumstantial evidence of the modified equilibrium, suppressed rotational instability with toroidal mode number n = 2. MPF injection experiments have also been applied to the STOR-M tokamak as a start-up and current drive method. Differences in the responses of targets especially relation with beta value and the self-organization feature will be studied.
Theory and observations of electrostatic ion waves in the cold Io torus
Barbosa, D. D.; Kurth, W. S.
1990-01-01
A study of the ELF plasma wave environment of the cold Io torus in Jupiter's magnetosphere is made. Voyager 1 data are presented which show three distinct types of electrostatic ion waves occurring there: the Buchsbaum ion-ion mode just below the proton cyclotron frequency f(cp), hydrogen Bernstein modes at (n + 1/2) f(cp), and lower hybrid waves near f(LHR). The presence of these waves at their characteristic frequencies is consistent with a predominantly heavy ion plasma composed of singly ionized sulfur and oxygen ions along with a small admixture of protons. The hydrogen Bernstein modes are tightly confined to the magnetic equator, occurring within + or - 4 deg of it, while the Buchsbaum mode is localized to the dense heavy ion plasma of the cold torus near the centrifugal equator. A general theory for excitation of the waves based on the ion pickup process is developed.
Modeling Variability of Plasma Conditions in the Io Torus
Delamere, P. A.; Bagenal, F.
2003-01-01
Telescopic observations an in situ measurements of the Io plasma torus show the density, temperature and composition to vary over time, sometimes up to a factor of 2. While previous models of the physical and chemical processes in the Io plasma torus have reasonably modeled the conditions of the Voyager 1 era, their authors have not addressed the observed variability nor explored the sensitivity of torus conditions to input parameters. In this paper we present a homogeneous torus model parameterized by five variables (transport timescale, neutral source strength, ratio of oxygen sulfur to atoms in the source, fraction of superthermal electrons, temperature of these hot electrons). The model incorporates the most recent data for ionization, recombination, charge exchange and radiative energy losses for the major torus species (S, S(sup +), S(sup ++), S(sup +++), O, O(sup +), O(sup ++). We solve equations of conservation of mass and energy to find equilibrium conditions for a set of input parameters. We compare model plasma conditions with those observed by Voyager 1 Voyager 2, and Cassini. Furthermore, we explore the sensitivity of torus conditions to each parameter. We find that (1) torus conditions are distinctly different for the Voyager 1, Voyager 2 and Cassini eras, (2) unique torus input parameters for any given era are poorly constrained given the wide range of solution space that is consistent with the range of observed torus conditions, (3) ion composition is highly sensitive to the specification of a non-thermal electron distribution, (4) neutral O/S source ratio is highly variable with model values ranging between 1.7 for Cassini to 4.0 for Voyager 1 conditions, (5) transport times range between 23 days for Voyager 2 to 50 days for Voyager 1 and Cassini, (6) neutral source strengths range between 7 to 30 x 10(sup -4) cm (sup -3) s(sup -1) which corresponds to a net production of 0.4 to 1.3 tons/s for a torus volume of 1.4 x 10(sup 31) cm(sup 3), or 38 R
Thomson scattering on ELMO Bumpy Torus
International Nuclear Information System (INIS)
Below 1012 cm-3 density, a Thomson scattering experiment is an exacting task. Aside from the low signal level, the core plasma in this instance is bathed in high-energy x rays, surrounded by a glowing molecular surface plasma, and heated steady state by microwaves. This means that the noise level from radiation is high and the environment is extremely harsh-so harsh that much effort is required to overcome system damage. In spite of this, the ELMO Bumpy Torus (EBT) system has proven itself capable of providing reliable n/sub e/ and T/sub e/ measurements at densities as low as 2 x 1011 cm-3. Radial scans across 20 cm of the plasma diameter have been obtained on a routine basis, and the resulting information has been a great help in understanding confinement in the EBT plasma. The bulk electron properties are revealed as flat profiles of n/sub e/ and T/sub e/, with density ranging from 0.5 to 2.0 x 1012 cm-3 and temperature decreasing from 100 to 20 eV as pressure in the discharge is increased at constant power. Evidence is presented for a suprathermal tail, which amounts to about 10% of the electron distribution at low pressures. The validity of this conclusion is supported by two independent sensitivity calibrations
Development of a repetitive compact torus injector
Onchi, Takumi; McColl, David; Dreval, Mykola; Rohollahi, Akbar; Xiao, Chijin; Hirose, Akira; Zushi, Hideki
2013-10-01
A system for Repetitive Compact Torus Injection (RCTI) has been developed at the University of Saskatchewan. CTI is a promising fuelling technology to directly fuel the core region of tokamak reactors. In addition to fuelling, CTI has also the potential for (a) optimization of density profile and thus bootstrap current and (b) momentum injection. For steady-state reactor operation, RCTI is necessary. The approach to RCTI is to charge a storage capacitor bank with a large capacitance and quickly charge the CT capacitor bank through a stack of integrated-gate bipolar transistors (IGBTs). When the CT bank is fully charged, the IGBT stack will be turned off to isolate banks, and CT formation/acceleration sequence will start. After formation of each CT, the fast bank will be replenished and a new CT will be formed and accelerated. Circuits for the formation and the acceleration in University of Saskatchewan CT Injector (USCTI) have been modified. Three CT shots at 10 Hz or eight shots at 1.7 Hz have been achieved. This work has been sponsored by the CRC and NSERC, Canada.
NATO Advanced Study Institute on Recent Advances in the Modeling of Hydrologic Systems
O’Connell, P
1991-01-01
Modeling of the rainfall-runoff process is of both scientific and practical significance. Many of the currently used mathematical models of hydrologic systems were developed a genera tion ago. Much of the effort since then has focused on refining these models rather than on developing new models based on improved scientific understanding. In the past few years, however, a renewed effort has been made to improve both our fundamental understanding of hydrologic processes and to exploit technological advances in computing and remote sensing. It is against this background that the NATO Advanced Study Institute on Recent Advances in the Modeling of Hydrologic Systems was organized. The idea for holding a NATO ASI on this topic grew out of an informal discussion between one of the co-directors and Professor Francisco Nunes-Correia at a previous NATO ASI held at Tucson, Arizona in 1985. The Special Program Panel on Global Transport Mechanisms in the Geo-Sciences of the NATO Scientific Affairs Division agreed to sp...
Definition study for temperature control in advanced protein crystal growth
Nyce, Thomas A.; Rosenberger, Franz; Sowers, Jennifer W.; Monaco, Lisa A.
1990-01-01
Some of the technical requirements for an expedient application of temperature control to advanced protein crystal growth activities are defined. Lysozome was used to study the effects of temperature ramping and temperature gradients for nucleation/dissolution and consecutive growth of sizable crystals and, to determine a prototype temperature program. The solubility study was conducted using equine serum albumin (ESA) which is an extremely stable, clinically important protein due to its capability to bind and transport many different small ions and molecules.
The Impact of the Dusty Torus on Obscured Quasar Halo Mass Measurements
DiPompeo, M. A.; Runnoe, J. C.; Hickox, R. C.; Myers, A. D.; Geach, J. E.
2016-04-01
Recent studies have found that obscured quasars cluster more strongly and are thus hosted by dark matter haloes of larger mass than their unobscured counterparts. These results pose a challenge for the simplest unification models, in which obscured objects are intrinsically the same as unobscured sources but seen through a dusty line of sight. There is general consensus that a structure like a "dusty torus" exists, meaning that this intrinsic similarity is likely the case for at least some subset of obscured quasars. However, the larger host halo masses of obscured quasars implies that there is a second obscured population that has an even higher clustering amplitude and typical halo mass. Here, we use simple assumptions about the host halo mass distributions of quasars, along with analytical methods and cosmological N-body simulations to isolate the signal from this population. We provide values for the bias and halo mass as a function of the fraction of the "non-torus obscured" population. Adopting a reasonable value for this fraction of ˜25% implies a non-torus obscured quasar bias that is much higher than the observed obscured quasar bias, because a large fraction of the obscured population shares the same clustering strength as the unobscured objects. For this non-torus obscured population, we derive a bias of ˜3, and typical halo masses of ˜3 × 1013 M⊙/h at z = 1. These massive haloes are likely the descendants of high-mass unobscured quasars at high redshift, and will evolve into members of galaxy groups at z = 0.
The impact of the dusty torus on obscured quasar halo mass measurements
DiPompeo, M. A.; Runnoe, J. C.; Hickox, R. C.; Myers, A. D.; Geach, J. E.
2016-07-01
Recent studies have found that obscured quasars cluster more strongly and are thus hosted by dark matter haloes of larger mass than their unobscured counterparts. These results pose a challenge for the simplest unification models, in which obscured objects are intrinsically the same as unobscured sources but seen through a dusty line of sight. There is general consensus that a structure like a `dusty torus' exists, meaning that this intrinsic similarity is likely the case for at least some subset of obscured quasars. However, the larger host halo masses of obscured quasars imply that there is a second obscured population that has an even higher clustering amplitude and typical halo mass. Here, we use simple assumptions about the host halo mass distributions of quasars, along with analytical methods and cosmological N-body simulations to isolate the signal from this population. We provide values for the bias and halo mass as a function of the fraction of the `non-torus-obscured' population. Adopting a reasonable value for this fraction of ˜25 per cent implies a non-torus-obscured-quasar bias that is much higher than the observed obscured quasar bias, because a large fraction of the obscured population shares the same clustering strength as the unobscured objects. For this non-torus-obscured population, we derive a bias of ˜3, and typical halo masses of ˜3 × 1013 M⊙ h-1 at z = 1. These massive haloes are likely the descendants of high-mass unobscured quasars at high redshift, and will evolve into members of galaxy groups at z = 0.
NATO Advanced Study Institute on Methods in Computational Molecular Physics
Diercksen, Geerd
1992-01-01
This volume records the lectures given at a NATO Advanced Study Institute on Methods in Computational Molecular Physics held in Bad Windsheim, Germany, from 22nd July until 2nd. August, 1991. This NATO Advanced Study Institute sought to bridge the quite considerable gap which exist between the presentation of molecular electronic structure theory found in contemporary monographs such as, for example, McWeeny's Methods 0/ Molecular Quantum Mechanics (Academic Press, London, 1989) or Wilson's Electron correlation in moleeules (Clarendon Press, Oxford, 1984) and the realization of the sophisticated computational algorithms required for their practical application. It sought to underline the relation between the electronic structure problem and the study of nuc1ear motion. Software for performing molecular electronic structure calculations is now being applied in an increasingly wide range of fields in both the academic and the commercial sectors. Numerous applications are reported in areas as diverse as catalysi...
Two intervals R\\'enyi entanglement entropy of compact free boson on torus
Liu, Feihu
2015-01-01
We compute the $N=2$ R\\'enyi entanglement entropy of two intervals at equal time in a circle, for the theory of a 2d compact complex free scalar at finite temperature. This is carried out by performing functional integral on a genus 3 ramified cover of the torus, wherein the quantum part of the integral is captured by the four point function of twist fields on the worldsheet torus, and the classical piece is given by summing over winding modes of the genus 3 surface onto the target space torus. The final result is given in terms of a product of theta function and certain multi-dimensional theta function. We demonstrate the T-duality invariance of the result. We also study its low temperature limit. In the case in which the size of the intervals and of their separation are much smaller than the whole system, our result is in exact agreement with the known result for two intervals on an infinite system at zero temperature \\cite{eeoftwo}. In the case in which the separation between the two intervals is much smal...
Periodic intensity variations in sulfur emissions from the Io plasma torus
Woodward, R. Carey, Jr.; Scherb, Frank; Roesler, Fred L.
1994-01-01
In November and December 1988, we acquired 157 spectra of (S II) lambda 6731 emissions from the Io plasma torus with a Fabry-Perot interferometer at the McMath-Pierce Solar Telescope facility on Kitt Peak. A major goal of this experiment was to extend our earlier studies of intensity variations in the plasma torus. Our earlier analysis (F. L. Roesler, F. Scherb, and R. J. Oliversen, 1984, of (S III) lambda 9531 emission spectra acquired in April 1982 had shown that the intensity of torus emissions varied periodically with a period of 10.20 +/- 0.06 hr (1-sigma uncertainty level), slightly longer than Jupiter's System 3 rotational period of 9.925 hr. We present here an reanalysis of our 1982 data revealing, in addition to the 10.20-hr period, a clear secondary periodicity at 9.95 +/- 0.906 hr. By constrast, we show that our new (S II) lambda 6731 data have a single period of 10.14 +/- 0.03 hr. which is neither the System 3 period nor the proposed 'System 4' period of 10.224 hr.
Advances of Studies on the Viral Proteins of PRRSV
Institute of Scientific and Technical Information of China (English)
Cao; Zongxi; Shi; Zhihai; Lin; Zhemin; Jiao; Peirong; Zhang; Guihong
2014-01-01
Porcine reproductive and respiratory syndrome( PRRS) is one of viral diseases with severe reproductive obstacle of pregnant sows and respiratory tract symptoms and higher mortality of piglets as characteristics,which is caused by porcine reproductive and respiratory syndrome virus( PRRSV). PRRS has brought great threats to swine industry in the world. The advances of studies on the viral proteins of PRRSV were reviewed from the genome,non-structural proteins and structural proteins of PRRSV.
Instanton-torus knot duality in 5d SQED and $SU(2)$ SQCD
Gorsky, A
2016-01-01
We briefly review the instanton-torus knot duality found in 5d SUSY gauge theories with one compact dimension. The fermion condensate turn out to be the generating function for the torus knot polynomials colored by the fundamental representation.
Minimal surfaces in the three-Sphere by doubling the Clifford Torus
Kapouleas, Nicolaos; Yang, Seong-Deog
2007-01-01
We construct embedded closed minimal surfaces in the round three-sphere, resembling two parallel copies of the Clifford torus, joined by m^2 small catenoidal bridges symmetrically arranged along a square lattice of points on the torus.
Tritium systems concepts for the next European torus (NET)
International Nuclear Information System (INIS)
The study deals with the design of the various tritium processing facilities that will be required for the Next European Torus (NET) design. The reference data for the design of the NET Tritium Systems was provided by the NET team. Significant achievements of this study were: (a) Identification of new ways of handling some problems for example: 1) Recovery of tritium from the helium purge of the lithium-ceramic blanket using a novel Adsoprtion and Catalytic Exchange Process, 2) A new way of combining fuel component separation and coolant water detritiation using cryogenic distillation, 3) The use of parasitic refrigeration for the cryogenic isotope separation, 4) Tritium extraction from effluent gas streams at their respective sources, 5) Attempt to eliminate the need for Air Cleanup Systems. (b) Identification of uncertainties, for example: composition of plasma exhaust, required helium purge rate of Li-Pb for tritium recovery, uncertainty in requirements for decontaminating blanket sectors, etc. (c) Review of ways to limit tritium permeation into steam by swamping with hydrogen and to provide quantitative estimates for this permeation
Physics and engineering assessments of spherical torus component test facility
International Nuclear Information System (INIS)
A broadly based study of the fusion engineering and plasma science conditions of a Component Test Facility (CTF), using the Spherical Torus or Spherical Tokamak (ST) configuration, have been carried out. The chamber systems testing conditions in a CTF are characterized by high fusion neutron fluxes Γn > 4.4x1013 n/s/cm2, over size scales > 105 cm2 and depth scales > 50 cm, delivering > 3 accumulated displacement per atom (dpa) per year. The desired chamber conditions can be provided by a CTF with R0 1.2 m, A = 1.5, elongation ∼ 3.2, Ip ∼ 9 MA, BT ∼ 2.5 T, producing a driven fusion burn using 36 MW of combined neutral beam and RF power. Relatively robust ST plasma conditions are adequate, which have been shown achievable [4] without active feedback manipulation of the MHD modes. The ST CTF will test the single-turn, copper alloy center leg for the toroidal field coil without an induction solenoid and neutron shielding, and require physics data on solenoid-free plasma current initiation, ramp-up, and sustainment to multiple MA level. A new systems code that combines the key required plasma and engineering science conditions of CTF has been prepared and utilized as part of this study. The results show high potential for a family of lowercost CTF devices to suit a variety of fusion engineering science test missions. (author)
An economic study of an advanced technology supersonic cruise vehicle
Smith, C. L.; Williams, L. J.
1975-01-01
A description is given of the methods used and the results of an economic study of an advanced technology supersonic cruise vehicle. This vehicle was designed for a maximum range of 4000 n.mi. at a cruise speed of Mach 2.7 and carrying 292 passengers. The economic study includes the estimation of aircraft unit cost, operating cost, and idealized cash flow and discounted cash flow return on investment. In addition, it includes a sensitivity study on the effects of unit cost, manufacturing cost, production quantity, average trip length, fuel cost, load factor, and fare on the aircraft's economic feasibility.
A scientific case study of an advanced LISA mission
International Nuclear Information System (INIS)
A brief status report of an ongoing scientific case study of the Advanced Laser Interferometer Antenna (ALIA) mission is presented. Key technology requirements and primary science objectives of the mission are covered in the study. Possible descope options for the mission and the corresponding compromise in science are also considered and compared. Our preliminary study indicates that ALIA holds promise in mapping out the mass and spin distribution of intermediate mass black holes possibly present in dense star clusters at low redshift as well as in shedding important light on the structure formation in the early Universe.
Study of consolidation chemotherapy in advanced epithelial ovarian carcinoma
Institute of Scientific and Technical Information of China (English)
Cheng Ning-hai; Huang Hui-fang; Pan Lin-ya; Shen Keng; Wu Ming; Yang Jia-xin
2007-01-01
Objective: A prospective randomized study was designed to evaluate the role of consolidation chemotherapy in advanced epithelial ovarian carcinoma.Methods: 50 patients with advanced epithelial ovarian carcinoma treated in our hospital during the period from March 2000 to October 2005 were enrolled in this study.All patients had achieved clinical complete remission by means of standard treatments, and were randomly divided into consolidation chemotherapy group and control group.Relapse rate, and disease-free survival(DFS) time were analyzed in both groups.Results: 24 patients were assigned in consolidation chemotherapy group, and 26 patients in control group.Tumor relapse interval in consolidation group was (26.5±7.4) months, vs.(16.8±7.0) months in control group respectively, P=0.001.Time to relapse(TTR) in consolidation group was (19.2±6.8) months, vs.(10.0±6.9)months in control group, P=0.002.Analysis of DFS time and overall survival time, Log Rank test:P=0.042 and P= 0.062, respectively.Conclusions: Consolidation chemotherapy could be the relevant factor that postpones tumor relapse interval and prolongs DFS time in advanced epithelial ovarian carcinoma patients who had achived chlinical complete remission.But so far the statistic result of our clinical study is beyond the conclusion that consolidation chemotherapy can decrease relapse rate or increase survival rate.Muhicenter randomized clinical trial should be performed to confirm the role of consolidation chemotherapy in advanced epithelial ovarian carcinoma.
From Canards of Folded Singularities to Torus Canards in a Forced van der Pol Equation
Burke, John; Desroches, Mathieu; Granados, Albert; Kaper, Tasso J.; Krupa, Martin; Vo, Theodore
2016-04-01
In this article, we study canard solutions of the forced van der Pol equation in the relaxation limit for low-, intermediate-, and high-frequency periodic forcing. A central numerical observation made herein is that there are two branches of canards in parameter space which extend across all positive forcing frequencies. In the low-frequency forcing regime, we demonstrate the existence of primary maximal canards induced by folded saddle nodes of type I and establish explicit formulas for the parameter values at which the primary maximal canards and their folds exist. Then, we turn to the intermediate- and high-frequency forcing regimes and show that the forced van der Pol possesses torus canards instead. These torus canards consist of long segments near families of attracting and repelling limit cycles of the fast system, in alternation. We also derive explicit formulas for the parameter values at which the maximal torus canards and their folds exist. Primary maximal canards and maximal torus canards correspond geometrically to the situation in which the persistent manifolds near the family of attracting limit cycles coincide to all orders with the persistent manifolds that lie near the family of repelling limit cycles. The formulas derived for the folds of maximal canards in all three frequency regimes turn out to be representations of a single formula in the appropriate parameter regimes, and this unification confirms the central numerical observation that the folds of the maximal canards created in the low-frequency regime continue directly into the folds of the maximal torus canards that exist in the intermediate- and high-frequency regimes. In addition, we study the secondary canards induced by the folded singularities in the low-frequency regime and find that the fold curves of the secondary canards turn around in the intermediate-frequency regime, instead of continuing into the high-frequency regime. Also, we identify the mechanism responsible for this
Turbulent equipartition pinch of toroidal momentum in spherical torus
International Nuclear Information System (INIS)
We present a new analytic expression for turbulent equipartition (TEP) pinch of toroidal angular momentum originating from magnetic field inhomogeneity of spherical torus (ST) plasmas. Starting from a conservative modern nonlinear gyrokinetic equation (Hahm et al 1988 Phys. Fluids 31 2670), we derive an expression for pinch to momentum diffusivity ratio without using a usual tokamak approximation of B ∝ 1/R which has been previously employed for TEP momentum pinch derivation in tokamaks (Hahm et al 2007 Phys. Plasmas 14 072302). Our new formula is evaluated for model equilibria of National Spherical Torus eXperiment (NSTX) (Ono et al 2001 Nucl. Fusion 41 1435) and Versatile Experiment Spherical Torus (VEST) (Chung et al 2013 Plasma Sci. Technol. 15 244) plasmas. Our result predicts stronger inward pinch for both cases, as compared to the prediction based on the tokamak formula. (paper)
Weak integrability of Hamiltonians on the two torus and rigidity
International Nuclear Information System (INIS)
We show that a C∞ k-basic Finsler metric on the two torus T2 whose geodesic flow preserves a codimension one C1,L foliation is in fact flat. Although integrable high energy levels of Hamiltonians on the torus are not flat in general, the C1,L integrability of k-basic Finsler geodesic flows on T2 implies flatness and in particular, C∞ integrability. We also show that a codimension one C1 foliation invariant by the geodesic flow of any Finsler metric on T2 must coincide with the Busemann foliation. A consequence of the above results is that the Hopf conjecture would be false for k-basic Finsler metrics on the two torus if and only if there exists a C0 integrable k-basic Finsler geodesic flow that is not C1,L integrable. (paper)
Recent case studies and advancements in probabilistic risk assessment
International Nuclear Information System (INIS)
During the period from 1977 to 1984, Pickard, Lowe and Garrick, Inc., had the lead in preparing several full scope probabilistic risk assessments for electric utilities. Five of those studies are discussed from the point of view of advancements and lessons learned. The objective and trend of these studies is toward utilization of the risk models by the plant owners as risk management tools. Advancements that have been made are in presentation ad documentation of the PRAs, generation of more understandable plant level information, and improvements in methodology to facilitate technology transfer. Specific areas of advancement are in the treatment of such issues as dependent failures, human interaction, and the uncertainty in the source term. Lessons learned cover a wide spectrum and include the importance of plant specific models for meaningful risk management, the role of external events in risk, the sensitivity of contributors to choice of risk index, and the very important finding that the public risk is extremely small. The future direction of PRA is to establish less dependence on experts for in-plant application. Computerizing the PRAs such that they can be accessed on line and interactively is the key
Advanced studies on the Polycapillary Optics use at XLab Frascati
Hampai, D.; Dabagov, S. B.; Cappuccio, G.
2015-07-01
X-ray analytical techniques are widely used in the world. By the way, due to the strong radiation-matter interaction, to design optical devices suitable for X-ray radiation remains still of wide interest. As a consequence of novel advanced material studies, in the last 30 years several typologies of X-ray lenses have been developed. In this work, a short review on the status of Polycapillary Optics (polyCO), from design and fabrication to various applications, has been presented making comparison of the results achieved by several groups through different X-ray optical elements. A focus is regarded for advanced X-ray imaging and spectroscopy tools based on combination of the modern polyCO hardware and the reconstruction software, available as homemade and commercially ones. Recent results (in three main fields, high resolution X-ray imaging, micro-XRF spectroscopy and micro-tomography) obtained at XLab Frascati have been discussed.
NATO Advanced Study Institute on Low Temperature Molecular Spectroscopy
1996-01-01
Molecular spectroscopy has achieved rapid and significant progress in recent years, the low temperature techniques in particular having proved very useful for the study of reactive species, phase transitions, molecular clusters and crystals, superconductors and semiconductors, biochemical systems, astrophysical problems, etc. The widening range of applications has been accompanied by significant improvements in experimental methods, and low temperature molecular spectroscopy has been revealed as the best technique, in many cases, to establish the connection between experiment and theoretical calculations. This, in turn, has led to a rapidly increasing ability to predict molecular spectroscopic properties. The combination of an advanced tutorial standpoint with an emphasis on recent advances and new perspectives in both experimental and theoretical molecular spectroscopy contained in this book offers the reader insight into a wide range of techniques, particular emphasis being given to supersonic jet and matri...
System dynamics studies of advanced fuel cycle scenarios
International Nuclear Information System (INIS)
This work describes dynamic analysis studies of possible U.S. deployment scenarios of advanced nuclear energy systems. Different scenarios of future nuclear energy demand and different spent nuclear fuel management strategies to respond to those demands are considered. The management strategies include once-through, limited recycling, and transitional and sustained recycling strategies. The scenarios descriptions, data, timeline, and analysis are provided. Comparisons between the once-through and the recycling strategies show that the continuation of the current once-through fuel cycle practice can lead to unfavorable consequences as the demand for nuclear energy increase in the US. Those consequences include substantial increase in the number of geologic repository sites, continued accumulation of weapons-usable materials, and inefficient use of limited uranium resources. The analysis presented here shows that those concerns can only be addressed by employing an advanced fuel cycle. (author)
First results from the Columbia Non-neutral Torus
International Nuclear Information System (INIS)
The Columbia Non-neutral Torus started operation in November 2004. CNT is an ultralow aspect ratio stellarator designed to study the physics of non-neutral plasmas confined on magnetic surfaces. It is created from a unique and simple coil set consisting of two pairs of planar circular coils. Hence, its coil set is simpler than that of any other stellarator, or any tokamak. The first results from CNT include detailed magnetic surface mappings, and initial pure electron plasma experiments. The magnetic surface mapping experiments confirm the existence of large high quality magnetic surfaces with last closed flux surface aspect ratios as low as 11 electrons fill the volume of the magnetic surfaces, and that the electron confinement time can be more than 10 milliseconds, despite the modest magnetic field strength (B<0.1 T), the lack of quasi-symmetry, and the presence of a macroscopic material object in the plasma (the emitter rod). Since the estimated drift escape time is less than 1 msec, the much longer confinement time is experimental evidence that an equilibrium exists for a pure electron plasma in a stellarator, as predicted from theory. The confinement time is observed to decrease with increasing neutral pressure, and decreasing magnetic field strength. We will report on these first experiments, and discuss the results of upcoming experiments that will provide more detailed information
Current drive experiments in the Helicity Injected Torus - II
Hamp, W. T.; Redd, A. J.; Jarboe, T. R.; Nelson, B. A.; O'Neill, R. G.; Raman, R.; Sieck, P. E.; Smith, R. J.; Mueller, D.
2006-10-01
The HIT-II spherical torus (ST) device has demonstrated four toroidal plasma current drive configurations to form and sustain a tokamak: 1) inductive (ohmic) current drive, 2) coaxial helicity injection (CHI) current drive, 3) CHI initiated plasmas with ohmic sustainment (CHI+OH), and 4) ohmically initiated plasmas with CHI edge current drive (OH+ECD). CHI discharges with a sufficiently high ratio of injector current to toroidal field current form a closed flux core, and amplify the injector poloidal flux through magnetic reconnection. CHI+OH plasmas are more robust than unassisted ohmic discharges, with a wider operating space and more efficient use of the transformer Volt-seconds. Finally, edge CHI can enhance the plasma current of an ohmic discharge without significantly degrading the quality of the discharge. Results will be presented for each HIT-II operating regime, including empirical performance scalings, applicable parametric operating spaces, and requirements to produce these discharges. Thomson scattering measurements and EFIT simulations are used to evaluate confinement in several representative plasmas. Finally, we outline extensions to the HIT-II CHI studies that could be performed with NSTX, SUNIST, or other ST devices.
New Capabilities and Results for the National Spherical Torus Experiment
Energy Technology Data Exchange (ETDEWEB)
M.G. Bell, R.E. Bell, D.A. Gates, S.M. Kaye, H. Kugel, B.P. LeBlanc, F.M. Levinton, R. Maingi, J.E. Menard, R. Raman, S.A. Sabbagh, D. Stutman and the NSTX Research Team
2008-02-29
The National Spherical Torus Experiment (NSTX) produces plasmas with toroidal aspect ratio as low as 1.25, which can be heated by up to 6 MW High-Harmonic Fast Waves and up to 7 MW of deuterium Neutral Beam Injection. Using new poloidal fields coils, plasmas with cross-section elongation up to 2.7, triangularity 0.8, plasma currents Ip up to 1.5 MA and normalized currents Ip/a·BT up to 7.5 MA/m·T have been achieved. A significant extension of the plasma pulse length, to 1.5 s at a plasma current of 0.7 MA, has been achieved by exploiting the bootstrap and NBI-driven currents to reduce the dissipation of poloidal flux. Inductive plasma startup has been supplemented by Coaxial Helicity Injection (CHI) and the production of persistent current on closed flux surfaces by CHI has now been demonstrated in NSTX. The plasma response to magnetic field perturbations with toroidal mode numbers n = 1 or 3 and the effects on the plasma rotation have been investigated using three pairs of coils outside the vacuum vessel. Recent studies of both MHD stability and of transport benefitted from improved diagnostics, including measurements of the internal poloidal field using the motional Stark effect (MSE). In plasmas with a region of reversed magnetic shear in the core, now confirmed by the MSE data, improved electron confinement has been observed.
Strike Point Control for the National Spherical Torus Experiment (NSTX)
Energy Technology Data Exchange (ETDEWEB)
Kolemen, E.; Gates, D. A.; Rowley, C. W.; Kasdin, N. J.; Kallman, J.; Gerhardt, S.; Soukhanovskii, V.; Mueller, D.
2010-07-09
This paper presents the first control algorithm for the inner and outer strike point position for a Spherical Torus (ST) fusion experiment and the performance analysis of the controller. A liquid lithium divertor (LLD) will be installed on NSTX which is believed to provide better pumping than lithium coatings on carbon PFCs. The shape of the plasma dictates the pumping rate of the lithium by channeling the plasma to LLD, where strike point location is the most important shape parameter. Simulations show that the density reduction depends on the proximity of strike point to LLD. Experiments were performed to study the dynamics of the strike point, design a new controller to change the location of the strike point to desired location and stabilize it. The most effective PF coils in changing inner and outer strike points were identified using equilibrium code. The PF coil inputs were changed in a step fashion between various set points and the step response of the strike point position was obtained. From the analysis of the step responses, PID controllers for the strike points were obtained and the controller was tuned experimentally for better performance. The strike controller was extended to include the outer-strike point on the inner plate to accommodate the desired low outer-strike points for the experiment with the aim of achieving "snowflake" divertor configuration in NSTX.
Renyi entropies of free bosons on the torus and holography
Datta, Shouvik
2014-01-01
We analytically evaluate the Renyi entropies for the two dimensional free boson CFT. The CFT is considered to be compactified on a circle and at finite temperature. The Renyi entropies S_n are evaluated for a single interval using the two point function of bosonic twist fields on a torus. For the case of the compact boson, the sum over the classical saddle points results in the Riemann-Siegel theta function associated with the A_{n-1} lattice. We then study the Renyi entropies in the decompactification regime. We show that in the limit when the size of the interval becomes the size of the spatial circle, the entanglement entropy reduces to the thermal entropy of free bosons on a circle. We then set up a systematic high temperature expansion of the Renyi entropies and evaluate the finite size corrections for free bosons. Finally we compare these finite size corrections both for the free boson CFT and the free fermion CFT with the one-loop corrections obtained from bulk three dimensional handlebody spacetimes w...
ITER - torus vacuum pumping system remote handling issues
International Nuclear Information System (INIS)
This report describes design issues concerning remote maintenance of the ITER torus vacuum pumping system. Key issues under investigation in this report are bearings for inert gas operation, transporter integration options, cryopump access, gate valve maintenance frequency, tritium effects on materials, turbomolecular pump design, and remote maintenance. Alternative bearing materials are explored for inert gas operation. Encapsulated motors and rotary feedthroughs offer an alternative option where space requirements are restrictive. A number of transporter options are studied. The preferred scheme depends on the shielded reconfigured ducts to prevent streaming and activation of RH (remote handling) equipment. A radiation mapping of the cell is required to evaluate this concept. Valve seal and bellow life are critical issues and need to be evaluated, as they have a direct bearing on the provision of adequate RH equipment to meet scheduled and unscheduled maintenance outages. The limited space on the inboard side of the cryopumps for RH equipment access requires a reconfigured duct and manifold. A modified shielded duct arrangement is proposed, which would provide more access space, reduced activation of components, and the potential for improved valve seal life. Work at Mound Laboratories has shown the adverse effects of tritium on some bearing lubricants. Silicone-based lubricants should be avoided. (11 refs., 2 tabs., 31 figs.)
Lopez-Rodriguez, E; Jones, T J; Nikutta, R; McMaster, L; Mason, R E; Elvis, M; Shenoy, D; Alonso-Herrero, A; Ramirez, E; Martin, O Gonzalez; Hoenig, S F; Levenson, N A; Almeida, C Ramos; Perlman, E
2015-01-01
We present J' and K' imaging linear polarimetric adaptive optics observations of NGC 1068 using MMT-Pol on the 6.5-m MMT. These observations allow us to study the torus from a magnetohydrodynamical (MHD) framework. In a 0.5" (30 pc) aperture at K', we find that polarisation arising from the passage of radiation from the inner edge of the torus through magnetically aligned dust grains in the clumps is the dominant polarisation mechanism, with an intrinsic polarisation of 7.0%$\\pm$2.2%. This result yields a torus magnetic field strength in the range of 4$-$82 mG through paramagnetic alignment, and 139$^{+11}_{-20}$ mG through the Chandrasekhar-Fermi method. The measured position angle (P.A.) of polarisation at K$'$ is found to be similar to the P.A. of the obscuring dusty component at few parsec scales using infrared interferometric techniques. We show that the constant component of the magnetic field is responsible for the alignment of the dust grains, and aligned with the torus axis onto the plane of the sky....
Quasiperiodicity and Torus Breakdown in a Power Electronic DC/DC Converter
DEFF Research Database (Denmark)
Zhusubaliyev, Zhanybai; Soukhoterin, Evgeniy; Mosekilde, Erik
2007-01-01
This paper discusses the mechanisms of torus formation and torus destruction in a dc/dc converter with relay control and hysteresis. We establish a chart of the dynamical modes in the input voltage versus load resistance parameter plane. This chart displays several different torus bifurcations...
Comments on Supersymmetric Yang-Mills Theory on a Noncommutative Torus
Li, Miao
1998-01-01
D0-brane theory on a torus with a nonvanishing B field is embedded into a string theory in the weak coupling limit. It is shown that the usual supersymmetric Yang-Mills theory on a noncommutative torus can not be the whole story. The Born-Infeld action survives the noncommutative torus limit.
Quadratically integrable geodesic flows on the torus and on the Klein bottle
Matveev, V. S.
1997-01-01
In the present paper we prove, that if the geodesic flow of a metric G on the torus T is quadratically integrable, then the torus T isometrically covers a torus with a Liouville metric on it, and describe the set of quadratically integrable geodesic flows on the Klein bottle.
On generating a diminimal set of polyhedral maps on the torus
Henry, Jennifer
2001-01-01
We develop a method to find a set of diminimal polyhedral maps on the torus from which all other polyhedral maps on the torus may be generated by face splitting and vertex splitting. We employ this method, though not to its completion, to find 53 diminimal polyhedral maps on the Torus.
Knotted pictures of the GHZ states on the surface of a trivial torus
International Nuclear Information System (INIS)
By means of the torus knot theory method, this paper presents the complete process of obtaining the knotted pictures of eight GHZ states on the surface of a trivial torus from the knotted pictures of eight basic three-qubit states on the surface of a trivial torus. Thus, we obtain eight knotted pictures 121 linkage on the ordinary plane. (general)
The rigidity of periodic frameworks as graphs on a fixed torus
Ross, Elissa
2012-01-01
We define periodic frameworks as graphs on the torus, using the language of gain graphs. We present some fundamental definitions and results about the infinitesimal rigidity of graphs on a torus of fixed size and shape, and find necessary conditions for the generic rigidity of pe- riodic frameworks on a d-dimensional fixed torus.
Rocket FUV Observations of the Io Plasma Torus During the Shoemaker-Levy/9 Impacts
Stern, S. A.; Slater, D.; Cash, W.; Wilkinson, E.; Green, J.; Gladstone, R.
1995-01-01
We observed the Io torus from 820-1140 A on universal time (UT) 20.25 July 1994 from a sounding rocket telescope/spectrograph. These observations serve as only the fourth published spectrum of the torus in this wavelength range, and the only far ultraviolet (FUV) data documenting the state of the torus during the Shoemaker Levy 9 Impacts.
The CLAS12 Torus Detector Magnet at Jefferson Laboratory
Energy Technology Data Exchange (ETDEWEB)
Luongo, Cesar [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Wiseman, Mark A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Kashy, David H. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Pastor, Orlando [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Ghoshal, Probir K. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Fair, Ruben J. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Ballard, Joshua T. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Legg, Robert A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Rajput-Ghoshal, Renuka [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Biallas, George H. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Elouadrhiri, Latifa [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Young, Glenn R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Rode, Claus H. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Velev, George [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Krave, Steven [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Nobrega, Fred [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Elementi, Luciano [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Makarov, Alexander [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
2016-06-01
The CLAS12 Torus is a toroidal superconducting magnet, part of the detector for the 12GeV accelerator upgrade at Jefferson Lab. The coils were wound/fabricated by Fermi Lab, with Jlab responsible for all other parts of the project scope, including design, integration, cryostating the individual coils, installation, cryogenics, I&C, etc. The paper provides an overview of the CLAS12 Torus magnet features, and serves as a status report of its installation in the experimental hall. Completion and commissioning of the magnet is expected in 2016.
The CLAS12 Torus Detector Magnet at Jefferson Laboratory
Energy Technology Data Exchange (ETDEWEB)
Luongo, Cesar [Jefferson Lab; Ballard, Joshua [Jefferson Lab; Biallas, George [Jefferson Lab; Elouadrhiri, Latifa [Jefferson Lab; Fair, Ruben [Jefferson Lab; Ghoshal, Probir [Jefferson Lab; Kashy, Dave [Jefferson Lab; Legg, Robert [Jefferson Lab; Pastor, Orlando [Jefferson Lab; Rajput-Ghoshal, Renuka [Jefferson Lab; Rode, Claus [Jefferson Lab; Wiseman, Mark [Jefferson Lab; Young, Glenn [Jefferson Lab; Elementi, Luciano [Fermilab; Krave, Steven [Fermilab; Makarov, Alexander [Fermilab; Nobrega, Fred [Fermilab; Velev, George [Fermilab
2015-12-17
The CLAS12 Torus is a toroidal superconducting magnet, which is part of the detector for the 12-GeV accelerator upgrade at Jefferson Laboratory (JLab). The coils were wound/fabricated by Fermilab, with JLab responsible for all other parts of the project scope, including design, integration, cryostating the individual coils, installation, cryogenics, I&C, etc. This paper provides an overview of the CLAS12 Torus magnet features and serves as a status report of its installation in the experimental hall. Completion and commissioning of the magnet is expected in 2016.
Pure Collective Precession Motion of High-Spin Torus Isomer
Ichikawa, T.; Matsuyanagi, K.; Maruhn, J. A.; Itagaki, N.
2013-01-01
We investigate the precession motion of the exotic torus configuration in high-spin excited states of $^{40}$Ca. For this aim, we use the three-dimensional time-dependent Hartree-Fock (TDHF) method. Although the high-spin torus isomer is a unique quantum object characterized by the alignment of angular momenta of independent single-particle motions, we find that the obtained moment of inertia for rotations about an axis perpendicular to the symmetry axis is close to the rigid-body value. We a...
New advances in pollination biology and the studies in China
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
Pollination biology is the study of the various biological features in relation to the event of pollen transfer. It is one of the central concerns of plant reproductive ecology and evolutionary biology. In this paper, we attempt to introduce the main advances and some new interests in pollination biology and make a brief review of the research work that has been done in China in recent years. We also give some insights into the study that we intend to carry out in this field in the future.
Advances in molecular genetic studies of primary dystonia
Directory of Open Access Journals (Sweden)
MA Ling-yan
2013-07-01
Full Text Available Dystonias are heterogeneous hyperkinetic movement disorders characterized by involuntary muscle contractions which result in twisting, repetitive movements and abnormal postures. In recent years, there was a great advance in molecular genetic studies of primary dystonia. This paper will review the clinical characteristics and molecular genetic studies of primary dystonia, including early-onset generalized torsion dystonia (DYT1, whispering dysphonia (DYT4, dopa-responsive dystonia (DYT5, mixed-type dystonia (DYT6, paroxysmal kinesigenic dyskinesia (DYT10, myoclonus-dystonia syndrome (DYT11, rapid-onset dystonia parkinsonism (DYT12, adult-onset cervical dystonia (DYT23, craniocervical dystonia (DYT24 and primary torsion dystonia (DYT25.
Wave Energy Study in China: Advancements and Perspectives
Institute of Scientific and Technical Information of China (English)
游亚戈; 郑永红; 沈永明; 吴必军; 刘荣
2003-01-01
The history and current status of research and development of wave energy in the world is briefly introduced. The main problems existing in these studies are pointed out. The description is focused on the current status and the advancements achieved in China. After analysis of the wave energy resources and practical situations in China, it is pointed out that the studies on wave energy should be not only concentrated on the conversion efficiency and costs of wave energy devices, but also focused on the technology of independent operation and stable output of electricity. Finally, the perspectives of application of wave energy in China are discussed.
Preliminary Study of Advanced Turboprops for Low Energy Consumption
Kraft, G. A.; Strack, W. C.
1975-01-01
The fuel savings potential of advanced turboprops (operational about 1985) was calculated and compared with that of an advanced turbofan for use in an advanced subsonic transport. At the design point, altitude 10.67 km and Mach 0.80, turbine-inlet temperature was fixed at 1590 K while overall pressure ratio was varied from 25 to 50. The regenerative turboprop had a pressure ratio of only 10 and an 85 percent effective rotary heat exchanger. Variable camber propellers were used with an efficiency of 85 percent. The study indicated a fuel savings of 33 percent, a takeoff gross weight reduction of 15 percent, and a direct operating cost reduction of 18 percent was possible when turboprops were used instead of the reference turbofan at a range of 10 200 km. These reductions were 28, 11, and 14 percent, respectively, at a range of 5500 km. Increasing overall pressure ratio from 25 to 50 saved little fuel and slightly increased takeoff gross weight.
Mirror Advanced Reactor Study (MARS) final report summary
International Nuclear Information System (INIS)
The Mirror Advanced Reactor Study (MARS) has resulted in an overview of a first-generation tandem mirror reactor. The central cell fusion plasma is self-sustained by alpha heating (ignition), while electron-cyclotron resonance heating and negative ion beams maintain the electrostatic confining potentials in the end plugs. Plug injection power is reduced by the use of high-field choke coils and thermal barriers, concepts to be tested in the Tandem Mirror Experiment-Upgrade (TMX-U) and Mirror Fusion Test Facility (MFTF-B) at Lawrence Livermore National Laboratory
The views of older Malaysians on advanced directive and advanced care planning: a qualitative study.
Htut, Y; Shahrul, K; Poi, P J H
2007-01-01
The provision of optimum care for the ageing population is dependent on the understanding of their views and values on end of life issues. A qualitative descriptive study was conducted to describe views of elderly Malaysians on Advanced Care Planning (henceforth ACP) and Advanced Directives (henceforth AD), and explore factors influencing these views. Fifteen elderly subjects with ages ranging from 65 to 83 years, representing different ethnic and religious groups in Malaysia were selected for in-depth interviews guided by a questionnaire. Five core themes were extracted from the interviews: 1) Considering the future 2) Contingency plans for future illnesses 3) Attitudes towards life prolonging treatment procedures 4) Doctor-patient relationships and 5) Influence of religion on decisions related to future illness. Despite the lack of knowledge on ACP and AD, older respondents were very receptive to their concept. Although the majority agreed on the importance of planning for future medical management and having open discussion on end of life issues with their doctor, they felt it unnecessary to make a formal written AD. Most felt that the future was best left to fate or God, and none had made any contingency plan for severe future illnesses citing religion as reason for this view. Cardiopulmonary resuscitation, mechanical ventilation and dialysis were considered by most to be invasive life prolonging treatments. We suggest that doctors initiate discussions on end of life care with every older patient and their family so as to promote awareness and introduce the concept of ACP/AD to a Malaysian setting. PMID:18330404
Quantum Torus symmetry of the KP, KdV and BKP hierarchies
Li, Chuanzhong; He, Jingsong
2013-01-01
In this paper, we construct the quantum Torus symmetry of the KP hierarchy and further derive the quantum torus constraint on the tau function of the KP hierarchy. That means we give a nice representation of the quantum Torus Lie algebra in the KP system by acting on its tau function. Comparing to the $W_{\\infty}$ symmetry, this quantum Torus symmetry has a nice algebraic structure with double indices. Further by reduction, we also construct the quantum Torus symmetries of the KdV and BKP hie...
A CLINICAL STUDY OF LOCALLY ADVANCED CARCINOMA OF BREAST
Directory of Open Access Journals (Sweden)
Mrinalini
2015-06-01
Full Text Available BACKGROUND : In India it is observed that most of the patients of breast cancer clinically present in late stage due to their ignorance of disease despite so much advancement in its detection and management. Locally advanced breast cancer (LABC accounts for 30 - 35% of all cases of breast cancers in India. This study aims to evaluate C linical features, Investigations, various Treatment modalities and the Clinico - pathological correlation & outcome of various treatment modalities of LABC, with special emphasis on Neo - adjuvant chemotherapy (NACT in Indian setting. MATERIAL AND METHOD : This was a non - randomised prospective observational study. We analyzed 57 patients of LABC Stage IIIB & IIIC presenting at Government Medical College, Nagpur, Maharashtra, a tertiary care C entre from September 2012 to November 2014. RESULTS : Stage IIIB comprised 84.21% patients while remaining 15.79% were having Stage IIIC disease. Skin involvement was observed in 91.23% patients. 15.79% showed supraclavicular lymph node involvement. 32 patients received NACT (2 to 6 cycles. Out of these 32, complete clinical response (cCR was 12.5%, partial response (cPR was 68.75% and pathological CR (pCR was 6.25% with Total Objective response (cCR+cPR 81.25%. Feasibility of Breast Conserving Surgery (BCS was observed in 12.5% patients. 25 patients underwent primary surgery followed by adjuvant chemotherapy. Modified Radical Mastectomy was performed in 89.48% patients. CONCLUSIONS : With overall clinical response of 81.25%, n eoadjuvant chemotherapy is the best treatment option for patients with Locally Advanced Breast Cancer with added advantage of in vivo testing the sensitivity of chemotherapeutic agents, early management of micrometastasis and down staging the primary tumour with feasibility of BCS. Patients presenting LABC constitute a diverse group for whic h a variety of treatment modalities should be instituted with co o rdinated treatment planning among surgeons
Legendrian and transverse cables of positive torus knots
DEFF Research Database (Denmark)
B. Etnyre, John; la Fountain, Douglas James; Tosun, Bulent
In this paper we classify Legendrian and transverse knots in the knot types obtained from positive torus knots by cabling. This classification allows us to demonstrate several new phenomena. Specifically, we show there are knot types that have non-destabilizable Legendrian representatives whose T...
Pro-Torus Actions on Poincaré Duality Spaces
Indian Academy of Sciences (India)
Ali Özkurt; Doğan Dönmez
2006-08-01
In this paper, it is shown that some of the results of torus actions on Poincaré duality spaces, Borel’s dimension formula and topological splitting principle to local weights, hold if `torus’ is replaced by `pro-torus’.
Elliptic open books on torus bundles over the circle
Etgü, Tolga
2006-01-01
As an application of the construction of open books on plumbed 3-manifolds, we construct elliptic open books on torus bundles over the circle. In certain cases these open books are compatible with Stein fillable contact structures and have minimal genus.
An Observational Perspective on the Drivers of Torus Evolution
Davies, R.
2015-09-01
I will begin by discussing the origin of the gas that makes up the torus. Observations show that gas flows in - either from the galaxy host or its environment - and settles in a thick disk on scales of 50pc. Even on these scales the column density is high enough to cause orientation dependent obscuration. Episodic, short-lived starbursts occuring in this region have a major impact on further gas inflow. This suggests that the torus is a dynamically evolving structure, the properties of which are, at least partially, dependent on gas flow from large scales. Turning to small scales, spatially resolved spectroscopy shows both ionised and molecular outflows originating on scales less than tens of parsecs. Despite this obvious influence of the AGN, I argue that (in contrast to the dust sublimation radius) the properties of the geometrically thick gas structure associated with the torus do not depend on AGN luminosity. This can make sense if the torus is sustained by a balance between inflow from large scales and outflow on small scales.
Summary of ELMO Bumpy Torus experiments from 1982 to 1984
International Nuclear Information System (INIS)
Experiments were conducted in the ELMO Bumpy Torus (EBT) from 1973 until 1984. A number of papers have been published on various aspects of the final two years of the EBT experiments. This report summarizes the final experimental conclusions and discusses issues that were not resolved. 46 refs., 12 figs., 1 tab
Modular differential equations for torus one-point functions
International Nuclear Information System (INIS)
It is shown that in a rational conformal field theory every torus one-point function of a given highest weight state satisfies a modular differential equation. We derive and solve these differential equations explicitly for some Virasoro minimal models. In general, however, the resulting amplitudes do not seem to be expressible in terms of standard transcendental functions
Spherical torus (ST) concept and its reactor implications
International Nuclear Information System (INIS)
A brief description of the spherical torus design is given. The design concept includes resistive demountable toroidal field coils, poloidal divertor for impurity control, oscillating-field current maintenance, RF initiation and ramp-up of the plasma current, and flowing liquid-metal breeding blanket. 4 refs., 6 figs
Global solvability for involutive systems on the torus
Directory of Open Access Journals (Sweden)
Cleber de Medeira
2013-11-01
Full Text Available In this article, we consider a class of involutive systems of n smooth vector fields on the torus of dimension n+1. We prove that the global solvability of this class is related to an algebraic condition involving Liouville forms and the connectedness of all sublevel and superlevel sets of the primitive of a certain 1-form associated with the system.
A Classification of Minimal Sets of Torus Homeomorphisms
Jaeger, Tobias; Passeggi, Alejandro
2011-01-01
We provide a classification of minimal sets of homeomorphisms of the two-torus, in terms of the structure of their complement. We show that this structure is exactly one of the following types: (1) a disjoint union of topological disks, or (2) a disjoint union of essential annuli and topological disks, or (3) a disjoint union of one doubly essential component and bounded topological disks. Periodic bounded disks can only occur in type 3. This result provides a framework for more detailed investigations, and additional information on the torus homeomorphism allows to draw further conclusions. In the non-wandering case, the classification can be significantly strengthened and we obtain that a minimal set other than the whole torus is either a periodic orbit, or the orbit of a periodic circloid, or the extension of a Cantor set. Further special cases are given by torus homeomorphisms homotopic to an Anosov, in which types 1 and 2 cannot occur, and the same holds for homeomorphisms homotopic to the identity with ...
Geometry of torus bundles in integrable Hamiltonian systems
Lukina, Olga
2008-01-01
Thesis is concerned with global properties of Lagrangian bundles, i.e. symplectic n-torus bundles, as these occur in integrable Hamiltonian systems. It treats obstructions to triviality and concerns with classification of such bundles, as well as with manifestations of global invariants in real-worl
Complete spectral data for analytic Anosov maps of the torus
Slipantschuk, Julia; Bandtlow, Oscar F.; Just, Wolfram
2016-01-01
Using analytic properties of Blaschke factors we construct a family of analytic hyperbolic diffeomorphisms of the torus for which the spectral properties of the associated transfer operator acting on a suitable Hilbert space can be computed explicitly. As a result, we obtain explicit expressions for the decay of correlations of analytic observables without resorting to any kind of perturbation argument.
Orbit transfer rocket engine technology program: Advanced engine study
Erickson, C. M.
1992-01-01
In Task D.6 of the Advanced Engine Study, three primary subtasks were accomplished: (1) design of parametric data; (2) engine requirement variation studies; and (3) vehicle study/engine study coordination. Parametric data were generated for vacuum thrusts ranging from 7500 lbf to 50,000 lbf, nozzle expansion ratios from 600 to 1200, and engine mixture ratios from 5:1 to 7:1. Failure Modes and Effects Analysis (FMEA) was used as a departure point for these parametric analyses. These data are intended to assist in definition and trade studies. In the Engine Requirements Variation Studies, the individual effects of increasing the throttling ratio from 10:1 to 20:1 and requiring the engine to operate at a maximum mixture ratio of 12:1 were determined. Off design engine balances were generated at these extreme conditions and individual component operating requirements analyzed in detail. Potential problems were identified and possible solutions generated. In the Vehicle Study/Engine Study coordination subtask, vehicle contractor support was provided as needed, addressing a variety of issues uncovered during vehicle trade studies. This support was primarily provided during Technical Interchange Meetings (TIM) in which Space Exploration Initiative (SEI) studies were addressed.
Forest fire advanced system technology (FFAST) conceptual design study
Nichols, J. David; Warren, John R.
1987-01-01
The National Aeronautics and Space Administration's Jet Propulsion Laboratory (JPL) and the U.S. Department of Agriculture (USDA) Forest Service completed a conceptual design study that defined an integrated forest fire detection and mapping system that will be based upon technology available in the 1990s. Potential system configuration options in emerging and advanced technologies related to the conceptual design were identified and recommended for inclusion as preferred system components. System component technologies identified for an end-to-end system include airborne mounted, thermal infrared (IR) linear array detectors, automatic onboard georeferencing and signal processing, geosynchronous satellite communications links, and advanced data integration and display. Potential system configuration options were developed and examined for possible inclusion in the preferred system configuration. The preferred system configuration will provide increased performance and be cost effective over the system currently in use. Forest fire management user requirements and the system component emerging technologies were the basis for the system configuration design. The conceptual design study defined the preferred system configuration that warrants continued refinement and development, examined economic aspects of the current and preferred system, and provided preliminary cost estimates for follow-on system prototype development.
Methods and advances in the study of aeroelasticity with uncertainties
Directory of Open Access Journals (Sweden)
Dai Yuting
2014-06-01
Full Text Available Uncertainties denote the operators which describe data error, numerical error and model error in the mathematical methods. The study of aeroelasticity with uncertainty embedded in the subsystems, such as the uncertainty in the modeling of structures and aerodynamics, has been a hot topic in the last decades. In this paper, advances of the analysis and design in aeroelasticity with uncertainty are summarized in detail. According to the non-probabilistic or probabilistic uncertainty, the developments of theories, methods and experiments with application to both robust and probabilistic aeroelasticity analysis are presented, respectively. In addition, the advances in aeroelastic design considering either probabilistic or non-probabilistic uncertainties are introduced along with aeroelastic analysis. This review focuses on the robust aeroelasticity study based on the structured singular value method, namely the μ method. It covers the numerical calculation algorithm of the structured singular value, uncertainty model construction, robust aeroelastic stability analysis algorithms, uncertainty level verification, and robust flutter boundary prediction in the flight test, etc. The key results and conclusions are explored. Finally, several promising problems on aeroelasticity with uncertainty are proposed for future investigation.
Engine Concept Study for an Advanced Single-Aisle Transport
Guynn, Mark D.; Berton, Jeffrey J.; Fisher, Kenneth L.; Haller, William J.; Tong, Michael; Thurman, Douglas R.
2009-01-01
The desire for higher engine efficiency has resulted in the evolution of aircraft gas turbine engines from turbojets, to low bypass ratio, first generation turbofans, to today's high bypass ratio turbofans. Although increased bypass ratio has clear benefits in terms of propulsion system metrics such as specific fuel consumption, these benefits may not translate into aircraft system level benefits due to integration penalties. In this study, the design trade space for advanced turbofan engines applied to a single aisle transport (737/A320 class aircraft) is explored. The benefits of increased bypass ratio and associated enabling technologies such as geared fan drive are found to depend on the primary metrics of interest. For example, bypass ratios at which mission fuel consumption is minimized may not require geared fan technology. However, geared fan drive does enable higher bypass ratio designs which result in lower noise. The results of this study indicate the potential for the advanced aircraft to realize substantial improvements in fuel efficiency, emissions, and noise compared to the current vehicles in this size class.
Radial and azimuthal dynamics of the Io plasma torus
Copper, Matthew
The moon Io orbits Jupiter emitting neutral particles from its volcanic surface. This emission is ionized and forms the Io plasma torus around Jupiter. The variation of conditions at Io and Jupiter lead to variations in the content of the plasma in the torus. Volcanoes on Io's surface erupt and change the rate of neutral input. Hot electrons (30--100 eV), whose abundances vary in azimuth, create highly ionized species. Radial variation in subcorotation velocities, velocities less than that of the motion of the dipole magnetic field, creates shears while maintaining coherent radial structure in the torus. Poorly understood changes in plasma density circulate through the torus creating the anomalous System IV behavior that has a period slightly longer than the rotation of Jupiter's magnetic field. This thesis summarizes the research that has produced a two-dimensional physical chemistry model, tested several existing theories about subcorotation velocities, System IV variation, and hot electrons, and adopted new methods of Io plasma torus analysis. In an attempt to understand important dynamics, the thesis modeled differing scenarios such as an initialized two-peak structure, a subcorotation profile dictated by mass loading and ionospheric conductivity, and a critical combination of two populations of hot electrons that accurately mimics the observed System IV phenomenon. This model was also used to solve the inverse problem of determining the best fit for the model parameters, neutral source input rate and radial transport rate, using observations of density, temperature, and composition. In addition the thesis shows the need for multi-dimensional modeling and the results from its groundbreaking two-dimensional model.
A feasibility study: Forest Fire Advanced System Technology (FFAST)
Mcleod, R. G.; Martin, T. Z.; Warren, J.
1983-01-01
The National Aeronautics and Space Administration/Jet Propulsion Laboratory and the United States Department of Agriculture Forest Service completed a feasibility study that examined the potential uses of advanced technology in forest fires mapping and detection. The current and future (1990's) information needs in forest fire management were determined through interviews. Analysis shows that integrated information gathering and processing is needed. The emerging technologies that were surveyed and identified as possible candidates for use in an end to end system include ""push broom'' sensor arrays, automatic georeferencing, satellite communication links, near real or real time image processing, and data integration. Matching the user requirements and the technologies yielded a ""strawman'' system configuration. The feasibility study recommends and outlines the implementation of the next phase for this project, a two year, conceptual design phase to define a system that warrants continued development.
Recent Advances in Proteomic Studies of Adipose Tissues and Adipocytes
Directory of Open Access Journals (Sweden)
Eun Young Kim
2015-02-01
Full Text Available Obesity is a chronic disease that is associated with significantly increased levels of risk of a number of metabolic disorders. Despite these enhanced health risks, the worldwide prevalence of obesity has increased dramatically over the past few decades. Obesity is caused by the accumulation of an abnormal amount of body fat in adipose tissue, which is composed mostly of adipocytes. Thus, a deeper understanding of the regulation mechanism of adipose tissue and/or adipocytes can provide a clue for overcoming obesity-related metabolic diseases. In this review, we describe recent advances in the study of adipose tissue and/or adipocytes, focusing on proteomic approaches. In addition, we suggest future research directions for proteomic studies which may lead to novel treatments of obesity and obesity-related diseases.
NATO Advanced Study Institute on Nonequilibrium Phonon Dynamics
1985-01-01
Phonons are always present in the solid state even at an absolute temperature of 0 K where zero point vibrations still abound. Moreover, phonons interact with all other excitations of the solid state and, thereby, influence most of its properties. Historically experimental information on phonon transport came from measurements of thermal conductivity. Over the past two decades much more, and much more detailed, information on phonon transport and on many of the inherent phonon interaction processes have come to light from experiments which use nonequilibrium phonons to study their dynamics. The resultant research field has most recently blossomed with the development of ever more sophisticated experimental and theoretical methods which can be applied to it. In fact, the field is moving so rapidly that new members of the research community have difficulties in keeping up to date. This NATO Advanced Study Institute (ASI) was organized with the objective of overcoming the information barrier between those expert...
NATO Advanced Study Institute on Buoyant Convection in Geophysical Flows
Fedorovich, E; Viegas, D; Wyngaard, J
1998-01-01
Studies of convection in geophysical flows constitute an advanced and rapidly developing area of research that is relevant to problems of the natural environment. During the last decade, significant progress has been achieved in the field as a result of both experimental studies and numerical modelling. This led to the principal revision of the widely held view on buoyancy-driven turbulent flows comprising an organised mean component with superimposed chaotic turbulence. An intermediate type of motion, represented by coherent structures, has been found to play a key role in geophysical boundary layers and in larger scale atmospheric and hydrospheric circulations driven by buoyant forcing. New aspects of the interaction between convective motions and rotation have recently been discovered and investigated. Extensive experimental data have also been collected on the role of convection in cloud dynamics and microphysics. New theoretical concepts and approaches have been outlined regarding scaling and parameteriz...
NATO Advanced Study Institute on Physics of New Laser Sources
Arecchi, F; Mooradian, Aram; Sona, Alberto
1985-01-01
This volume contains the lectures and seminars presented at the NATO Advanced Study Institute on "Physics of New Laser Sources", the twelfth course of the Europhysics School of Quantum Electronics, held under the supervision of the Quantum Electronics Division of the European Physical Society. The Institute was held at Centro "I Cappuccini" San Miniato, Tuscany, July 11-21, 1984. The Europhysics School of Quantum Electronics was started in 1970 with the aim of providing instruction for young researchers and advanced students already engaged in the area of quantum electronics or for those wishing to switch into this area after working previously in other areas. From the outset, the School has been under the direction of Prof. F. T. Arecchi, then at the University of Pavia, now at the University of Florence, and Dr. D. Roess of Heraeus, Hanau. In 1981, Prof. H. Walther, University of Munich and Max-Planck Institut fur Quantenoptik joined as co-director. Each year the Directors choose a subj~ct of particular int...
Fraissard, Jacques
1984-01-01
This volume contains the lectures presented at an Advanced Study Institute on "Magnetic Resonance Techniques in Fossil Energy Problems," which was held at the village of Maleme, Crete, in July of 1983. As of this writing, a different popular attitude prevails from that when the ASI was proposed as far as how critical the world energy picture is. In the popular press, a panglossian attitude (the "petroleum glut" of the 80's) has replaced the jeremiads of the 70's ( a catastrophic "energy crisis"). Yet, there are certain important constants: (a) for the foreseeable future, fossil energy sources (petroleum, coal, oil shale, etc. ) will continue to be of paramount importance; and (b) science and technology of the highest order are needed to extend the fossil ener~y resource base and to utilize it in a cost-effective manner that is also environmentally acceptable. It is precisely this second item that this volume addresses. The volume introduces the phenomenology of magnetic resonance ~n a unified and detailed man...
Byrne, Vicky; Orndoff, Evelyne; Poritz, Darwin; Schlesinger, Thilini
2013-01-01
All human space missions require significant logistical mass and volume that will become an excessive burden for long duration missions beyond low Earth orbit. The goal of the Advanced Exploration Systems (AES) Logistics Reduction & Repurposing (LRR) project is to bring new ideas and technologies that will enable human presence in farther regions of space. The LRR project has five tasks: 1) Advanced Clothing System (ACS) to reduce clothing mass and volume, 2) Logistics to Living (L2L) to repurpose existing cargo, 3) Heat Melt Compactor (HMC) to reprocess materials in space, 4) Trash to Gas (TTG) to extract useful gases from trash, and 5) Systems Engineering and Integration (SE&I) to integrate these logistical components. The current International Space Station (ISS) crew wardrobe has already evolved not only to reduce some of the logistical burden but also to address crew preference. The ACS task is to find ways to further reduce this logistical burden while examining human response to different types of clothes. The ACS task has been broken into a series of studies on length of wear of various garments: 1) three small studies conducted through other NASA projects (MMSEV, DSH, HI-SEAS) focusing on length of wear of garments treated with an antimicrobial finish; 2) a ground study, which is the subject of this report, addressing both length of wear and subject perception of various types of garments worn during aerobic exercise; and 3) an ISS study replicating the ground study, and including every day clothing to collect information on perception in reduced gravity in which humans experience physiological changes. The goal of the ground study is first to measure how long people can wear the same exercise garment, depending on the type of fabric and the presence of antimicrobial treatment, and second to learn why. Human factors considerations included in the study consist of the Institutional Review Board approval, test protocol and participants' training, and a web
The dusty torus in the Circinus galaxy: a dense disk and the torus funnel
Tristram, K R W; Jaffe, W; Meisenheimer, K; Hönig, S F; Kishimoto, M; Schartmann, M; Weigelt, G
2013-01-01
(Abridged) With infrared interferometry it is possible to resolve the nuclear dust distributions that are commonly associated with the dusty torus in active galactic nuclei (AGN). The Circinus galaxy hosts the closest Seyfert 2 nucleus and previous interferometric observations have shown that its nuclear dust emission is well resolved. To better constrain the dust morphology in this active nucleus, extensive new observations were carried out with MIDI at the Very Large Telescope Interferometer. The emission is distributed in two distinct components: a disk-like emission component with a size of ~ 0.2 $\\times$ 1.1 pc and an extended component with a size of ~ 0.8 $\\times$ 1.9 pc. The disk-like component is elongated along PA ~ 46{\\deg} and oriented perpendicular to the ionisation cone and outflow. The extended component is elongated along PA ~ 107{\\deg}, roughly perpendicular to the disk component and thus in polar direction. It is interpreted as emission from the inner funnel of an extended dust distribution ...
Studies of a modular advanced stellarator reactor ASRA6C
International Nuclear Information System (INIS)
This study is directed towards the clarification of critical issues of advanced modular stellerator reactors exploiting the inherent potential of steady state operation, and is not a point design study of a reactor. Critical technology issues arise from the three-dimensional magnetic field structure. The first wall, blanket and shield are more complex than those of axi-symmetric systems, but this is eased at moderate to large aspect ratio typical of stellarators. Several blanket options have been studied and a thin blanket (21 cm) was the first choice for the design. Superconducting modular coils were investigated with respect to the conductor and mechanical supports. From the analysis of forces and stresses caused by the electromagnetic loads the coils are considered to be feasible, although shear stresses might pose a critical issue. Demountable intermagnetic support elements were designed for use at separation areas between the cryostat modules. A scheme for remote reactor maintenance was also developed. The plasma physics issues of different configurations were studied using extrapolations of transport behaviour and equilibrium from theory and present experiments. These studies indicate that the confinement and equilibrium behaviour is adequate for ignited operation at an average value of 5% beta. Impurities may pose a critical issue. Several impurity control operations were investigated; a pumped limiter configuration utilizing the 'ergodic layer' at the plasma edge was chosen for edge plasma and impurity control. A general conclusion of the study is that the modular stellerator configuration offers interesting prospects regarding the development towards steady-state reactors. (orig.)
Studies of a modular advanced stellarator reactor ASRA6C
International Nuclear Information System (INIS)
This study is directed towards the clarification of critical issues of advanced modular stellerator reactors exploiting the inherent potential of steady state operation, and is not a point design study of a reactor. Critical technology issues arise from the three-dimensional magnetic field structure. The first wall, blanket and shield are more complex than those of axi-symmetric systems, but this is eased at moderate to large aspect ratio typical of stellerators. Several blanket options have been studied and a thin blanket (21 cm) was the first choice for the design. Superconducting modular coils were investigated with respect to the conductor and mechanical supports. From the analysis of forces and stresses caused by the electromagnetic loads the coils are considered to be feasible, although shear stresses might pose a critical issue. Demountable intermagnetic support elements were designed for use at separation areas between the cryostat modules. A scheme for remote reactor maintenance was also developed. The plasma physics issues of different configurations were studied using extrapolations of transort behaviour and equilibrium from theory and present experiments. These studies indicate that the confinement and equilibrium behaviour is adequate for ignited operation at an average value of 5% beta. Impurities may pose a critical issue. Several impurity control operations were investigated; a pumped limiter configuration utilizing the 'ergodic layer' at the plasma edge was chosen for edge plasma and impurity control. A general conclusion of the study is that the modular stellerator configuration offers interesting prospects regarding the development towards steady-state reactors. (orig.)
Systems cost and performance analysis for a spherical torus-based volume neutron source
International Nuclear Information System (INIS)
A cost and performance analysis of a spherical torus-based volume neutron source (ST-VNS) is performed using the SUPERCODE systems code. An ST-VNS, proposed as a reduced-cost option for testing the nuclear technologies necessary for tokamak power reactors, will cost about 25% of the construction cost of the International Thermonuclear Experimental Reactor Engineering Design Activities (ITER-EDA) when it is operating in an initial test phase with 0.5 MW m-2 wall load. Advanced operation at 5 MW m-2 wall load is possible with surface elongation κ=3, safety factor q95=10, confinement enhancement factor H=2.3, and Troyon beta limit βN=5%, at a direct cost of about 30% that of the ITER-EDA. There is a narrow region βN and H space which is useful for attaining high neutron wall loads. (orig.)
Operational Regimes of the National Spherical Torus Experiment; TOPICAL
International Nuclear Information System (INIS)
The National Spherical Torus Experiment (NSTX) is a proof-of-principle experiment designed to study the physics of Spherical Tori (ST), i.e., low-aspect-ratio toroidal plasmas. Important issues for ST research are whether the high-eta stability and reduced transport theoretically predicted for this configuration can be realized experimentally. In NSTX, the commissioning of a digital real-time plasma control system, the provision of flexible heating systems, and the application of wall conditioning techniques were instrumental in achieving routine operation with good confinement. NSTX has produced plasmas with R/a(approx) 0.85 m/0.68 m, A(approx) 1.25, Ip* 1.1 MA, BT= 0.3-0.45 T, k* 2.2, d* 0.5, with auxiliary heating by up to 4 MW of High Harmonic Fast Waves, and 5 MW of 80 keV D0 Neutral Beam Injection (NBI). The energy confinement time in plasmas heated by NBI has exceeded 100 ms and a toroidal beta (bT= 2m0 and lt;p and gt;/BT02, where BT0 is the central vacuum toroidal magnetic field) up to 22% has be en achieved. HHFW power of 2.3 MW has increased the electron temperature from an initial 0.4 keV to 0.9 keV both with and without producing a significant density rise in the plasma. The early application of both NBI and HHFW heating has slowed the penetration of the inductively produced plasma current, modifying the current profile and, thereby, the observed MHD stability
Tectothalamic inhibitory projection neurons in the avian torus semicircularis.
Ito, Tetsufumi; Atoji, Yasuro
2016-09-01
Inhibitory feedforward projection is one of key features of the organization of the central auditory system. In mammals, the inferior colliculus (IC) is the origin of a substantial inhibitory feedforward projection as well as an excitatory projection to the auditory thalamus. This inhibitory feedforward projection is provided by large γ-aminobutyric acid (GABA)ergic (LG) neurons, which are characterized by their receipt of dense excitatory axosomatic terminals positive for vesicular glutamate transporter (VGLUT) 2. In the avian torus semicircularis (TS), which is the homolog of the IC, neither the homology of cell types nor the presence of inhibitory feedforward inhibition have been established. In this study, we tested the presence of LG neurons in pigeon and chicken by neuroanatomical techniques. The TS contained two types of GABAergic neurons of different soma size. Of these, larger GABA + cells were encircled by dense VGLUT2 + axosomatic terminals. Ultrastructural analyses revealed that more than 30% of the perimeter of a large GABA+, but not small GABA + or GABA-, soma was covered by presumptive excitatory axosomatic terminals, suggesting that large GABA + cells are the sole recipient of dense excitatory axosomatic synapses. After injection of a retrograde tracer into the auditory thalamus, many retrogradely labeled neurons were found bilaterally in the TS, a few of which were GABA+. Almost all tectothalamic GABA + neurons had large somata, and received dense VGLUT2 + axosomatic terminals. These results clearly demonstrated the presence of LG neurons in birds. The similar morphology of LG neurons implies that the function of tectothalamic inhibition is similar among amniotes. J. Comp. Neurol. 524:2604-2622, 2016. © 2016 Wiley Periodicals, Inc. PMID:26850847
Obscuring Torus Geometry from the NuSTAR Survey of Swift/BAT AGN
Balokovic, Mislav; Harrison, Fiona; NuSTAR
2016-06-01
The Nuclear Spectroscopic Telescope Array (NuSTAR) has enabled studies of the local active galactic nuclei (AGN) to extend into the spectral window above 10 keV with unprecedented spatial resolution and two orders of magnitude better sensitivity than any other instrument operating in that energy range. As a part of its long-term extragalactic program NuSTAR is surveying the nearby population of AGN detected at hard X-ray energies by the Swift Burst Alert Telescope (Swift/BAT). I will present spectroscopic results based on NuSTAR and Swift observations of ~150 Swift/BAT AGN surveyed in the first three years of NuSTAR operation. This sample forms an atlas of the highest quality hard X-ray spectra available to date for a large number of AGN, providing unprecedented insight into the variety AGN spectra in the hard X-ray band. In addition to phenomenology, which is an essential ingredient of Cosmic X-ray Background studies, it is possible to use new fitting models to directly probe the geometry of the toroidal obscurer (torus). Its main spectral features lie within the NuSTAR bandpass, making it possible to test the common assumption that a similar Compton-thick torus exists around essentially every Seyfert-type AGN. I will discuss torus geometry constraints based on the X-ray spectra in relation to those from other wavelengths, the effects on interpretation of high-redshift AGN observations, and the limitations of the current results.
The ARIES Advanced and Conservative Tokamak Power Plant Study
International Nuclear Information System (INIS)
Tokamak power plants are studied with advanced and conservative design philosophies to identify the impacts on the resulting designs and to provide guidance to critical research needs. Incorporating updated physics understanding and using more sophisticated engineering and physics analysis, the tokamak configurations have developed a more credible basis compared with older studies. The advanced configuration assumes a self-cooled lead lithium blanket concept with SiC composite structural material with 58% thermal conversion efficiency. This plasma has a major radius of 6.25 m, a toroidal field of 6.0 T, a q95 of 4.5,a βtotalN of 5.75, an H98 of 1.65, an n/nGr of 1.0, and a peak divertor heat flux of 13.7 MW/m2. The conservative configuration assumes a dual-coolant lead lithium blanket concept with reduced-activation ferritic martensitic steel structural material and helium coolant, achieving a thermal conversion efficiency of 45%. The plasma has a major radius of 9.75 m, a toroidal field of 8.75 T, a q95 of 8.0, a βtotalN of 2.5, an H98 of 1.25, an n/nGr of 1.3, and a peak divertor heat flux of 10 MW/m2. The divertor heat flux treatment with a narrow power scrape-off width has driven the plasmas to larger major radius. Edge and divertor plasma simulations are targeting a basis for high radiated power fraction in the divertor, which is necessary for solutions to keep the peak heat flux in the range 10 to 15 MW/m2. Combinations of the advanced and conservative approaches show intermediate sizes. A new systems code using a database approach has been used and shows that the operating point is really an operating zone with some range of plasma and engineering parameters and very similar costs of electricity. Other papers in this issue provide more detailed discussion of the work summarized here
Study on advanced plasma propulsion for interplanetary manned space missions
International Nuclear Information System (INIS)
The prerequisite for manned space missions in the twenty first century is the advanced high performance transportation. Plasma thrusters are known to provide higher specific impulse than conventional chemical thrusters, and because of this advantage, plasma thrusters have been used on satellites for several decades. For successful deep space missions, an even higher performance propulsion system is required, and the Ion Cyclotron Resonance Heating (ICRH) plasma thruster is one of the candidates. An ICRH thruster can provide not only high specific impulse but also operational flexibility, which is the most important aspect of the thruster. For the feasibility study of the ICRH thruster, a small sized, proof-of-principle-type experiment is currently ongoing under the KAIST-KBSI collaboration research. If it turns out to be successful, a larger scale experiment will be planned at HANBIT magnetic mirror device
Study of nanoscale structural biology using advanced particle beam microscopy
Boseman, Adam J.
This work investigates developmental and structural biology at the nanoscale using current advancements in particle beam microscopy. Typically the examination of micro- and nanoscale features is performed using scanning electron microscopy (SEM), but in order to decrease surface charging, and increase resolution, an obscuring conductive layer is applied to the sample surface. As magnification increases, this layer begins to limit the ability to identify nanoscale surface structures. A new technology, Helium Ion Microscopy (HIM), is used to examine uncoated surface structures on the cuticle of wild type and mutant fruit flies. Corneal nanostructures observed with HIM are further investigated by FIB/SEM to provide detailed three dimensional information about internal events occurring during early structural development. These techniques are also used to reconstruct a mosquito germarium in order to characterize unknown events in early oogenesis. Findings from these studies, and many more like them, will soon unravel many of the mysteries surrounding the world of developmental biology.
NATO Advanced Study Institute on Hamiltonian Dynamical Systems and Applications
2008-01-01
Physical laws are for the most part expressed in terms of differential equations, and natural classes of these are in the form of conservation laws or of problems of the calculus of variations for an action functional. These problems can generally be posed as Hamiltonian systems, whether dynamical systems on finite dimensional phase space as in classical mechanics, or partial differential equations (PDE) which are naturally of infinitely many degrees of freedom. This volume is the collected and extended notes from the lectures on Hamiltonian dynamical systems and their applications that were given at the NATO Advanced Study Institute in Montreal in 2007. Many aspects of the modern theory of the subject were covered at this event, including low dimensional problems as well as the theory of Hamiltonian systems in infinite dimensional phase space; these are described in depth in this volume. Applications are also presented to several important areas of research, including problems in classical mechanics, continu...
Advanced methods for the study of PWR cores
International Nuclear Information System (INIS)
This document gathers the transparencies presented at the 6. technical session of the French nuclear energy society (SFEN) in October 2003. The transparencies of the annual meeting are presented in the introductive part: 1 - status of the French nuclear park: nuclear energy results, management of an exceptional climatic situation: the heat wave of summer 2003 and the power generation (J.C. Barral); 2 - status of the research on controlled thermonuclear fusion (J. Johner). Then follows the technical session about the advanced methods for the study of PWR reactor cores: 1 - the evolution approach of study methodologies (M. Lambert, J. Pelet); 2 - the point of view of the nuclear safety authority (D. Brenot); 3 - the improved decoupled methodology for the steam pipe rupture (S. Salvatores, J.Y. Pouliquen); 4 - the MIR method for the pellet-clad interaction (renovated IPG methodology) (E. Baud, C. Royere); 5 - the improved fuel management (IFM) studies for Koeberg (C. Cohen); 6 - principle of the methods of accident study implemented for the European pressurized reactor (EPR) (F. Foret, A. Ferrier); 7 - accident studies with the EPR, steam pipe rupture (N. Nicaise, S. Salvatores); 8 - the co-development platform, a new generation of software tools for the new methodologies (C. Chauliac). (J.S.)
Advanced studies on Simulation Methodologies for very Complicated Fracture Phenomena
International Nuclear Information System (INIS)
Although nowadays, computational techniques are well developed, for Extremely Complicated Fracture Phenomena, they are still very difficult to simulate, for general engineers, researchers. To overcome many difficulties in those simulations, we have developed not only Simulation Methodologies but also theoretical basis and concepts. We sometimes observe extremely complicated fracture patterns, especially in dynamic fracture phenomena such as dynamic crack branching, kinking, curving, etc. For examples, although the humankind, from primitive men to modern scientists such as Albert Einstein had watched the post-mortem patterns of dynamic crack branching, the governing condition for the onset of the phenomena had been unsolved until our experimental study. From in these studies, we found the governing condition of dynamic crack bifurcation, as follows. When the total energy flux per unit time into a propagating crack tip reaches the material crack resistance, the crack braches into two cracks [total energy flux criterion]. The crack branches many times whenever the criterion is satisfied. Furthermore, the complexities also arise due to their time-dependence and/or their-deformation dependence. In order to make it possible to simulate such extremely complicated fracture phenomena, we developed many original advanced computational methods and technologies. These are (i) moving finite element method based on Delaunay automatic triangulation (MFEMBOAT), path independent, (ii) equivalent domain integral expression of the dynamic J integral associated with a continuous auxiliary function, (iii) Mixed phase path-prediction mode simulation, (iv) implicit path prediction criterion. In this paper, these advanced computational methods are thoroughly explained together with successful comparison with the experimental results. Since multiple dynamic crack branching phenomena may be most complicated fracture due to complicated fracture paths, and its time dependence (transient
Energy Technology Data Exchange (ETDEWEB)
Kim, Chang Hyo; Kim, Seung Cho; Kim, Taek Kyum; Cho, Jin Young; Lee, Hyun Cheol; Lee, Jung Hun; Jung, Gu Young [Seoul National University, Seoul (Korea, Republic of)
1995-08-01
The neutronics design system of the advanced PWR consists of (i) hexagonal cell and fuel assembly code for generation of homogenized few-group cross sections and (ii) global core neutronics analysis code for computations of steady-state pin-wise or assembly-wise core power distribution, core reactivity with fuel burnup, control rod worth and reactivity coefficients, transient core power, etc.. The major research target of the first year is to establish the numerical method and solution of multi-group diffusion equations for neutronics code development. Specifically, the following studies are planned; (i) Formulation of various numerical methods such as finite element method(FEM), analytical nodal method(ANM), analytic function expansion nodal(AFEN) method, polynomial expansion nodal(PEN) method that can be applicable for the hexagonal core geometry. (ii) Comparative evaluation of the numerical effectiveness of these methods based on numerical solutions to various hexagonal core neutronics benchmark problems. Results are follows: (i) Formulation of numerical solutions to multi-group diffusion equations based on numerical methods. (ii) Numerical computations by above methods for the hexagonal neutronics benchmark problems such as -VVER-1000 Problem Without Reflector -VVER-440 Problem I With Reflector -Modified IAEA PWR Problem Without Reflector -Modified IAEA PWR Problem With Reflector -ANL Large Heavy Water Reactor Problem -Small HTGR Problem -VVER-440 Problem II With Reactor (iii) Comparative evaluation on the numerical effectiveness of various numerical methods. (iv) Development of HEXFEM code, a multi-dimensional hexagonal core neutronics analysis code based on FEM. In the target year of this research, the spatial neutronics analysis code for hexagonal core geometry(called NEMSNAP-H temporarily) will be completed. Combination of NEMSNAP-H with hexagonal cell and assembly code will then equip us with hexagonal core neutronics design system. (Abstract Truncated)
On the fields of a torus and the role of the vector potential
Energy Technology Data Exchange (ETDEWEB)
Carron, N.J. [Mission Research Corporation, P.O. Drawer 719, Santa Barbara, California 93102 (United States)
1995-08-01
A toroidal current distribution has nonvanishing exterior vector potential {bold A}, but zero exterior field {bold B}={del}{times}{bold A}=0. This property, together with the absence of fringing fields as in a cylindrical solenoid, makes it convenient for studies involving the vector potential in a field-free region, such as the Aharonov--Bohm effect, or the effect of {bold A} in a Josephson junction. We present an immediate general result of magnetostatics, and use it to easily compute {bold A} for a torus, to visualize the static vector potential for any current distribution, and to show how one can construct a current distribution to produce any desired {bold A}. When the torus current {ital I} varies in time, nonzero quasistatic fields {bold E}({ital t}) and {bold B}({ital t}) are produced ({bold E}{similar_to}{omega}{ital I}/{ital r}{sup 3} and {bold B}{similar_to}{omega}{sup 2}{ital I}/{ital r}{sup 2}). Radiation is also produced, with the radiation pattern of an {ital electric} {ital dipole}. The torus provides a counterexample to the common erroneous notion that if all multipole moments of a current distribution vanish then quasistatic fields and radiation must also vanish. We then formulate Maxwell`s equations in a way that obviates the role of gauge transformations. This ``gauge irrelevant`` form clarifies the relation of potentials to current sources, isolating the role of the transverse part of {bold A}. The general result from magnetostatics is extended to time-varying sources, revealing a seldom recognized symmetry of Maxwell`s equations, and showing how one can visualize {bold A} for an arbitrary time-dependent current source. {copyright} {ital 1995} {ital American} {ital Association} {ital of} {ital Physics} {ital Teachers}.
A study of reset mode in advanced alarm system simulator
International Nuclear Information System (INIS)
An automation function has been widely applied in main control room of nuclear power plants. That leads to a new issue of human-automation interaction, which considers human operational performance in automated systems. In this research is the automation alarm reset in the advanced alarm system (AAS) of Advanced Nuclear Power Plant in Taiwan. Since alarms are very crucial for the understanding of the status of the plant as well as the reset function of alarm system will be changed from fully manual to fully automatic, it is very important to test and evaluate the performance and the effect of reset modes in AAS. The purpose of this paper is to evaluate the impact of the auto-reset alarm system on the plant performance and on operators' preference and task load. To develop a dynamic simulator as an AAS was conducted to compare manual and automatic reset function of alarm system on task performance and subjective ratings of task workload, comprehension, and preference. The simulation includes PCTRAN model and alarm software processing. The final results revealed that, using the auto-reset mode, participants had lower task load index (TLX) on effort in the first test trial and was more satisfied in multiple tasks condition. In contrast, using manual reset mode, participants were more satisfied on alarm handling, monitoring, and decision making. In other words, either reset mode in the study has unique features to assist operator, but is insufficient. The reset function in AAS therefore should be very flexible. Additionally, the experimental results also pointed out that the user interfaces need to be improved. Those experiences will be helpful for human factors verification and validation in the near future. (authors)
Topical advances and recent studies in paleolimnological research
Directory of Open Access Journals (Sweden)
Thomas J. Whitmore
2014-04-01
Full Text Available Paleolimnology combines the disciplines of limnology, geology and ecology, but because of challenges that separate investigators from direct knowledge about past lake conditions, the field is multidisciplinary by necessity. As a result, paleolimnology is influenced continuously by advances in many disciplines. As with limnological studies in recent decades, paleolimnology has diverged largely from the ecological and theoretical focuses of early investigators, but recent studies demonstrate the need for more integration of ecological and paleolimnological research. This paper provides a brief overview of recent paleolimnological investigations that have addressed questions related to theoretical ecology, as well as applied lake-management and climate research issues. We examine the use of transfer function models for estimating past water-quality conditions, and important caveats expressed by investigators about limitations in the development and use of such models. Paleolimnological research has contributed new insights about biological, physical and chemical processes in lakes that have been subject to change because of climate drivers and anthropogenic influences. These findings are relevant to predicting how lakes will respond to climate change, and will require new management approaches in the future. As the range of paleolimnological studies expands, there will be greater need for basic limnological research in order for paleolimnological investigators to better understand how sediments reflect lake processes of those regions.
Advance study of fiber-reinforced self-compacting concrete
International Nuclear Information System (INIS)
Incorporation in concrete composition of steel macro- and micro – fiber reinforcement with structural function increases the degree of ductility of typically brittle cement-containing composites, which in some cases can replace completely or partially conventional steel reinforcement in the form of rods and meshes. Thus, that can reduce manufacturing, detailing and placement of conventional reinforcement, which enhances productivity and economic efficiency of the building process. In this paper, six fiber-reinforced with different amounts of steel fiber cement-containing self-compacting compositions are investigated. The results of some of their main strength-deformation characteristics are presented. Advance approach for the study of structural and material properties of these type composites is proposed by using the methods of industrial computed tomography. The obtained original tomography results about the microstructure and characteristics of individual structural components make it possible to analyze the effective macro-characteristics of the studied composites. The resulting analytical data are relevant for the purposes of multi-dimensional modeling of these systems. Multifactor structure-mechanical analysis of the obtained with different methods original scientific results is proposed. It is presented a conclusion of the capabilities and effectiveness of complex analysis in the studies to characterize the properties of self-compacting fiber-reinforced concrete
NATO Advanced Study Institute on Atoms in Strong Fields
Clark, Charles; Nayfeh, Munir
1990-01-01
This book collects the lectures given at the NATO Advanced Study Institute on "Atoms in Strong Fields", which took place on the island of Kos, Greece, during the two weeks of October 9-21,1988. The designation "strong field" applies here to an external electromagnetic field that is sufficiently strong to cause highly nonlinear alterations in atomic or molecular struc ture and dynamics. The specific topics treated in this volume fall into two general cater gories, which are those for which strong field effects can be studied in detail in terrestrial laboratories: the dynamics of excited states in static or quasi-static electric and magnetic fields; and the interaction of atoms and molecules with intense laser radiation. In both areas there exist promising opportunities for research of a fundamental nature. An electric field of even a few volts per centimeter can be very strong on the atom ic scale, if it acts upon a weakly bound state. The study of Rydberg states with high reso lution laser spectroscop...
Advance study of fiber-reinforced self-compacting concrete
Mironova, M.; Ivanova, M.; Naidenov, V.; Georgiev, I.; Stary, J.
2015-10-01
Incorporation in concrete composition of steel macro- and micro - fiber reinforcement with structural function increases the degree of ductility of typically brittle cement-containing composites, which in some cases can replace completely or partially conventional steel reinforcement in the form of rods and meshes. Thus, that can reduce manufacturing, detailing and placement of conventional reinforcement, which enhances productivity and economic efficiency of the building process. In this paper, six fiber-reinforced with different amounts of steel fiber cement-containing self-compacting compositions are investigated. The results of some of their main strength-deformation characteristics are presented. Advance approach for the study of structural and material properties of these type composites is proposed by using the methods of industrial computed tomography. The obtained original tomography results about the microstructure and characteristics of individual structural components make it possible to analyze the effective macro-characteristics of the studied composites. The resulting analytical data are relevant for the purposes of multi-dimensional modeling of these systems. Multifactor structure-mechanical analysis of the obtained with different methods original scientific results is proposed. It is presented a conclusion of the capabilities and effectiveness of complex analysis in the studies to characterize the properties of self-compacting fiber-reinforced concrete.
Advance study of fiber-reinforced self-compacting concrete
Energy Technology Data Exchange (ETDEWEB)
Mironova, M., E-mail: mirona@imbm.bas.bg; Ivanova, M., E-mail: magdalena.ivanova@imbm.bas.bg; Naidenov, V., E-mail: valna53@mail.bg [Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev str., bl. 4, Sofia 1113 (Bulgaria); Georgiev, I., E-mail: ivan.georgiev@parallel.bas.bg [Institute of Information and Communication Technologies & Institute of Mathematics and Informatics, Bulgarian Academy of Sciences, Acad. G. Bonchev str., Sofia 1113 (Bulgaria); Stary, J., E-mail: stary@ugn.cas.cz [Institute of Geonics Czech Academy of Sciences, Studentska str., Ostrava 1768 (Czech Republic)
2015-10-28
Incorporation in concrete composition of steel macro- and micro – fiber reinforcement with structural function increases the degree of ductility of typically brittle cement-containing composites, which in some cases can replace completely or partially conventional steel reinforcement in the form of rods and meshes. Thus, that can reduce manufacturing, detailing and placement of conventional reinforcement, which enhances productivity and economic efficiency of the building process. In this paper, six fiber-reinforced with different amounts of steel fiber cement-containing self-compacting compositions are investigated. The results of some of their main strength-deformation characteristics are presented. Advance approach for the study of structural and material properties of these type composites is proposed by using the methods of industrial computed tomography. The obtained original tomography results about the microstructure and characteristics of individual structural components make it possible to analyze the effective macro-characteristics of the studied composites. The resulting analytical data are relevant for the purposes of multi-dimensional modeling of these systems. Multifactor structure-mechanical analysis of the obtained with different methods original scientific results is proposed. It is presented a conclusion of the capabilities and effectiveness of complex analysis in the studies to characterize the properties of self-compacting fiber-reinforced concrete.
Advanced mathematical study and the development of conditional reasoning skills.
Directory of Open Access Journals (Sweden)
Nina Attridge
Full Text Available Since the time of Plato, philosophers and educational policy-makers have assumed that the study of mathematics improves one's general 'thinking skills'. Today, this argument, known as the 'Theory of Formal Discipline' is used in policy debates to prioritize mathematics in school curricula. But there is no strong research evidence which justifies it. We tested the Theory of Formal Discipline by tracking the development of conditional reasoning behavior in students studying post-compulsory mathematics compared to post-compulsory English literature. In line with the Theory of Formal Discipline, the mathematics students did develop their conditional reasoning to a greater extent than the literature students, despite them having received no explicit tuition in conditional logic. However, this development appeared to be towards the so-called defective conditional understanding, rather than the logically normative material conditional understanding. We conclude by arguing that Plato may have been correct to claim that studying advanced mathematics is associated with the development of logical reasoning skills, but that the nature of this development may be more complex than previously thought.
Constraining clumpy dusty torus models using optimized filter sets
Almeida, A Asensio Ramos \\and C Ramos
2012-01-01
Recent success in explaining several properties of the dusty torus around the central engine of active galactic nuclei has been gathered with the assumption of clumpiness. The properties of such clumpy dusty tori can be inferred by analyzing spectral energy distributions (SEDs), sometimes with scarce sampling given that large aperture telescopes and long integration times are needed to get good spatial resolution and signal. We aim at using the information already present in the data and the assumption of clumpy dusty torus, in particular, the CLUMPY models of Nenkova et al., to evaluate the optimum next observation such that we maximize the constraining power of the new observed photometric point. To this end, we use the existing and barely applied idea of Bayesian adaptive exploration, a mixture of Bayesian inference, prediction and decision theories. The result is that the new photometric filter to use is the one that maximizes the expected utility, which we approximate with the entropy of the predictive d...
A Riemann-Roch theorem for the noncommutative two torus
Khalkhali, Masoud; Moatadelro, Ali
2014-12-01
We prove the analogue of the Riemann-Roch formula for the noncommutative two torus Aθ = C(Tθ2)equipped with an arbitrary translation invariant complex structure and a Weyl factor represented by a positive element k ∈C∞(Tθ2). We consider a topologically trivial line bundle equipped with a general holomorphic structure and the corresponding twisted Dolbeault Laplacians. We define a spectral triple (Aθ , H , D) that encodes the twisted Dolbeault complex of Aθ and whose index gives the left hand side of the Riemann-Roch formula. Using Connes' pseudodifferential calculus and heat equation techniques, we explicitly compute the b2 terms of the asymptotic expansion of Tr(e-tD2) . We find that the curvature term on the right hand side of the Riemann-Roch formula coincides with the scalar curvature of the noncommutative torus recently defined and computed in Connes and Moscovici (2014) and independently computed in Fathizadeh and Khalkhali (2014).
Performance of a 12-coil superconducting 'bumpy torus' magnet facility.
Roth, J. R.; Holmes, A. D.; Keller, T. A.; Krawczonek, W. M.
1972-01-01
The NASA-Lewis 'bumpy torus' facility consists of 12 superconducting coils, each 19 cm ID and capable of 3.0 tesla on their axes. The coils are equally spaced around a toroidal array with a major diameter of 1.52 m, and are mounted with the major axis of the torus vertical in a single vacuum tank 2.6 m in diameter. Final shakedown tests of the facility mapped out its magnetic, cryogenic, vacuum, mechanical, and electrical performance. The facility is now ready for use as a plasma physics research facility. A maximum magnetic field on the magnetic axis of 3.23 teslas has been held for a period of more than sixty minutes without a coil normalcy.
Drift wave instability in the Io plasma torus
Huang, T. S.; Hill, T. W.
1991-01-01
A linear normal mode analysis of the drift wave instability in the Io plasma torus was carried out on the basis of the Richmond (1973) and Huang et al. (1990) analyses of drift waves in the vicinity of the earth's plasmapause. Results indicate that the outer torus boundary is linearly unstable to the growth of electrostatic drift waves. It is shown that the linear growth rate is proportional to the ion drift frequency and to the ratio of the flux tube charge content to the Jovian ionospheric Pedersen conductance. It is also shown that various theoretical models of global radial transport in Jupiter's atmosphere (including corotating convection, interchange diffusion, and transient flux tube convection) can be understood as plausible nonlinear evolutions of electrostatic drift waves.
Fukaya categories of the torus and Dehn surgery
Lekili, Yanki
2011-01-01
This paper is a companion to the authors' forthcoming work extending Heegaard Floer theory from closed 3-manifolds to compact 3-manifolds with two boundary components via quilted Floer cohomology. We describe the first interesting case of this theory: the invariants of 3-manifolds bounding S^2 union T^2, regarded as modules over the Fukaya category of the punctured 2-torus. We extract a short proof of exactness of the Dehn surgery triangle in Heegaard Floer homology. We show that A_\\infty-structures on the graded algebra A formed by the cohomology of two basic objects in the Fukaya category of the punctured 2-torus are governed by just two parameters (m^6,m^8), extracted from the Hochschild cohomology of A. For the Fukaya category itself, m^6 is nonzero.
Temporal and spatial variations in the Io torus
Morgan, J. S.
1985-01-01
Spectroscopic measurements of lines from both forbidden S II and forbidden O II in the Io torus taken on 15 nights spread over four months in 1981 are presented and discussed. An east-west asymmetry was observed in the optical emissions, showing larger western intensities and a more diffuse and radially extensive nebula to the east. Two configurations of forbidden S II longitudinal asymmetry were stable over at least four days. Longitudinal structure was not detected in either the forbidden O II intensity or the plasma density as measured by the forbidden O II and S II doublet ratios. A radial variation in the ratio of O II/S II was observed, with the ratio being largest near Io's orbit. Monthly variability was detected in both the intensity and density of the torus.
Design progress for the ITER torus and neutral beam cryopumps
International Nuclear Information System (INIS)
The ITER torus and neutral beam cryopumps are complex vacuum pumps which will be designed to the build-to-print level stage for the call for tender for manufacturing. Although being completely different in size, the pumps share the same concept of cryosorption on activated charcoal. Thus, the design procedure itself can follow the same generic workflow. The requirements on the pumps are summarized and the status of design evolution is described. Both design packages require specific R and D for experimental clarification and design validation. Two examples for this approach are given, namely the characterization of the closing forces of the torus pump inlet valve, and the measurement of hydraulic resistance coefficients of hydroformed components.
Energy Technology Data Exchange (ETDEWEB)
B. Jones; G. Taylor; P.C. Efthimion; T. Munsat
2004-01-28
Measurement of the magnetic field in a spherical torus by observation of harmonic overlap frequencies in the electron Bernstein wave (EBW) spectrum has been previously suggested [V.F. Shevchenko, Plasma Phys. Reports 26 (2000) 1000]. EBW mode conversion to X-mode radiation has been studied in the Current Drive Experiment-Upgrade spherical torus, [T. Jones, Ph.D. thesis, Princeton University, 1995] with emission measured at blackbody levels [B. Jones et al., Phys. Rev. Lett. 90 (2003) article no. 165001]. Sharp transitions in the thermally emitted EBW spectrum have been observed for the first two harmonic overlaps. These transition frequencies are determined by the magnetic field and electron density at the mode conversion layer in accordance with hot-plasma wave theory. Prospects of extending this measurement to higher harmonics, necessary in order to determine the magnetic field profile, and high beta equilibria are discussed for this proposed magnetic field diagnostic.
Jet and Torus Orientations in High Redshift Radio Galaxies
Drouart, G.; De Breuck, C.; Vernet, J.; Laing, R. A.; Seymour, N; Stern, D; de Haas, M.; Pier, E. A.; Rocca-Volmerange, B.
2012-01-01
We examine the relative orientation of radio jets and dusty tori surrounding the AGN in powerful radio galaxies at z > 1. The radio core dominance R = P(20 GHz) /P(500 MHz) serves as an orientation indicator, measuring the ratio between the anisotropic Doppler-beamed core extended core emission and the isotropic lobe emission. Assuming a fixed cylindrical geometry for the hot, dusty torus, we derive its inclination i by fitting optically-thick radiative transfer models to spectral energy dist...
Exact solution of an su(n) spin torus
Hao, Kun; Li, Guang-Liang; Yang, Wen-Li; Shi, Kangjie; Wang, Yupeng
2016-01-01
The trigonometric su(n) spin chain with anti-periodic boundary condition (su(n) spin torus) is demonstrated to be Yang-Baxter integrable. Based on some intrinsic properties of the R-matrix, certain operator product identities of the transfer matrix are derived. These identities and the asymptotic behavior of the transfer matrix together allow us to obtain the exact eigenvalues in terms of an inhomogeneous T-Q relation via the off-diagonal Bethe Ansatz.
On non-trivial additive cocycles on the torus
Rozhdestvenskii, A. V.
2008-02-01
We construct a family of functions f with zero mean on a multidimensional torus possessing a very high degree of smoothness, such that the equation \\displaystyle w(x+\\alpha)-w(x)=f(x) has no measurable solutions w for any badly approximable vector \\alpha. For every vector \\alpha admitting an arbitrary prescribed degree of simultaneous Diophantine approximation we construct a cocycle of extremal smoothness that is asymptotically normal in the strong sense. Bibliography: 19 titles.
High energy density fusing using the Compact Torus
International Nuclear Information System (INIS)
My remarks are concerned with employing the Compact Torus magnetic field configuration to produce fusion energy. In particular, I would like to consider high energy density regimes where the pressures generated extend well beyond the strength of materials. Under such conditions, where nearby walls are vaporized and pushed aside each shot, the technological constraints are very different from usual magnetic fusion and may admit opportunities for an improved fusion reactor design. 5 refs., 3 figs
Bogomolny equations for vortices in the noncommutative torus
International Nuclear Information System (INIS)
We derive Bogomolny-type equations for the abelian Higgs model defined on the noncommutative torus and discuss its vortex like solutions. To this end, we carefully analyze how periodic boundary conditions have to be handled in noncommutative space and discuss how vortex solutions are constructed. We also consider the extension to an U(2) x U(1) model, a simplified prototype of the noncommutative standard model
Foresight Study on Advanced Conversion Technologies of Fossil Fuels
International Nuclear Information System (INIS)
The Observatorio de Prospectiva Tecnologica Industrial (OPTI) is a Foundation supported by the Ministry of Industry and Energy, (MINER) and has as main objective to provide a basic information and knowledge on technology evolution. This information will be accessible to the Administration and to the Companies and can be taking into account in planning and decision making of technology policies. Ciemat is member of OPTI and is the organism in charge of the actions in the Energy sector. CIEMAT has the responsibility on the realisation of the sector studies to get in three years (1998 to 2001) a foresight vision of the critical technology topics. The OPTI integrated strategic plan undertake the analysis of other seven technology sectors, with the same criteria on methodological aspects. Delphi method was used for the realization of the studies. It consisted of a survey conducted in two rounds using a questionnaire to check the experts opinion. The time frame of the studies was defined from 1999 to 2015. The study presented in this document has been performed by CIEMAT in the second stage of the OPTI activities. The main goal behind this study is to identify the advanced clean and efficient technologies for the conversion of fossil fuels to promote in our country. The questionnaire was addressed to 250 experts and the response rate was about the 37%, ratifying the final results. The spanish position and the barriers for the development of each technology has been determined and also the recommended measures to facilitate their performance in the future. This basic information is consider of main interest, taking in account the actual energetic situation with a foreseeable demand increase and fossil fuels dependence. (Author) 17 refs
X-ray production experiments on the RACE Compact Torus Accelerator
International Nuclear Information System (INIS)
The Purpose of the Compact Torus Accelerator (CTA) program at LLNL is to prove the principle of a unique accelerator concept based on magnetically confined compact torus (CT) plasma rings and to study applications. Successful achievement of these goals could lead to a high power-density driver for many applications including an intense x-ray source for nuclear weapons effects simulation and an inertial fusion driver. Fusion applications and a description of the CTA concept are included in a companion paper at this conference. This paper will describe the initial experiments on soft x-ray production conducted on the plasma Ring ACcelerator Experiment (RACE) and compare the results to modeling studies. The experiments on CT stagnation and soft x-ray production were conducted with unfocused rings as a first of CT dynamics and the physics of x-ray production. The x-ray fluences observed are consistent with expectations based on calculations employing a radiation-hydrodynamics code. We conclude with a diffusion of future x-ray production studies that can be conducted on RACE and a possible multi-megajoule upgrade
NATO Advanced Study Institute on Turbulence, Weak and Strong
Cardoso, O
1994-01-01
The present volume comprises the contributions of some of the participants of the NATO Advance Studies Institute "Turbulence, Weak and Strong", held in Cargese, in August 1994. More than 70 scientists, from seniors to young students, have joined to gether to discuss and review new (and not so new) ideas and developments in the study of turbulence. One of the objectives of the School was to incorporate, in the same meeting, two aspects of turbulence, which are obviously linked, and which are often treated sep arately: fully developed turbulence (in two and three dimensions) and weak turbulence (essentially one and two-dimensional systems). The idea of preparing a dictionary rather than ordinary proceedings started from the feeling that the terminology of turbulence includes many long, technical, poorly evocative words, which are usually not understood by people exterior to the field, and which might be worth explaining. Students who start working in the field of turbulence face a sort of curious situation:...
NATO Advanced Study Institute on Chemical Transport in Melasomatic Processes
1987-01-01
As indicated on the title page, this book is an outgrowth of the NATO Advanced Study Institute (ASI) on Chemical Transport in Metasomatic Processes, which was held in Greece, June 3-16, 1985. The ASI consisted of five days of invited lectures, poster sessions, and discussion at the Club Poseidon near Loutraki, Corinthia, followed by a two-day field trip in Corinthia and Attica. The second week of the ASI consisted of an excursion aboard M/S Zeus, M/Y Dimitrios II, and the M/S Irini to four of the Cycladic Islands to visit, study, and sample outstanding exposures of metasomatic activity on Syros, Siphnos, Seriphos, and Naxos. Nine teen invited lectures and 10 session chairmen/discussion leaders participated in the ASI, which was attended by a total of 92 professional scientists and graduate stu dents from 15 countries. Seventeen of the invited lectures and the Field Excursion Guide are included in this volume, together with 10 papers and six abstracts representing contributed poster sessions. Although more...
Torus mapper: a code for dynamical models of galaxies
Binney, James
2015-01-01
We present a freely downloadable software package for modelling the dynamics of galaxies, which we call the Torus Mapper (TM). The package is based around `torus mapping', which is a non-perturbative technique for creating orbital tori for specified values of the action integrals. Given an orbital torus and a star's position at a reference time, one can compute its position at any other time, no matter how remote. One can also compute the velocities with which the star will pass through any given point and the contribution it will make to the time-averaged density there. A system of angle-action coordinates for the given potential can be created by foliating phase space with orbital tori. Such a foliation is facilitated by the ability of TM to create tori by interpolating on a grid of tori. We summarise the advantages of using TM rather than a standard time-stepper to create orbits, and give segments of code that illustrate applications of TM in several contexts, including setting up initial conditions for an...
The nuclear dust lane of Circinus: collimation without a torus
Mezcua, M; Fernández-Ontiveros, J A; Tristram, K R W
2016-01-01
In some AGN, nuclear dust lanes connected to kpc-scale dust structures provide all the extinction required to obscure the nucleus, challenging the role of the dusty torus proposed by the Unified Model. In this letter we show the pc-scale dust and ionized gas maps of Circinus constructed using sub-arcsec-accuracy registration of infrared VLT AO images with optical \\textit{Hubble Space Telescope} images. We find that the collimation of the ionized gas does not require a torus but is caused by the distribution of dust lanes of the host galaxy on $\\sim$10 pc scales. This finding questions the presumed torus morphology and its role at parsec scales, as one of its main attributes is to collimate the nuclear radiation, and is in line with interferometric observations which show that most of the pc-scale dust is in the polar direction. We estimate that the nuclear dust lane in Circinus provides $1/3$ of the extinction required to obscure the nucleus. This constitutes a conservative lower limit to the obscuration at t...
Pure Collective Precession Motion of High-Spin Torus Isomer
Ichikawa, T; Maruhn, J A; Itagaki, N
2013-01-01
We investigate the precession motion of the exotic torus configuration in high-spin excited states of $^{40}$Ca. For this aim, we use the three-dimensional time-dependent Hartree-Fock (TDHF) method. Although the high-spin torus isomer is a unique quantum object characterized by the alignment of angular momenta of independent single-particle motions, we find that the obtained moment of inertia for rotations about an axis perpendicular to the symmetry axis is close to the rigid-body value. We also analyze the microscopic structure of the precession motion using the random-phase approximation (RPA) method for high-spin states. In the RPA calculation, the precession motion of the torus isomer is generated by coherent superposition of many one-particle-one-hole excitations across the sloping Fermi surface that strongly violates the time-reversal symmetry. By comparing results of the TDHF and the RPA calculations, we find that the precession motion obtained by the TDHF calculation is a pure collective motion well d...
Feasibility study on the development of advanced LWR fuel technology
Energy Technology Data Exchange (ETDEWEB)
Jung, Youn Ho; Sohn, D. S.; Jeong, Y. H.; Song, K. W.; Song, K. N.; Chun, T. H.; Bang, J. G.; Bae, K. K.; Kim, D. H. and others
1997-07-01
Worldwide R and D trends related to core technology of LWR fuels and status of patents have been surveyed for the feasibility study. In addition, various fuel cycle schemes have been studied to establish the target performance parameters. For the development of cladding material, establishment of long-term research plan for alloy development and optimization of melting process and manufacturing technology were conducted. A work which could characterize the effect of sintering additives on the microstructure of UO{sub 2} pellet has been experimentally undertaken, and major sintering variables and their ranges have been found in the sintering process of UO{sub 2}-Gd{sub 2}O{sub 3} burnable absorber pellet. The analysis of state of the art technology related to flow mixing device for spacer grid and debris filtering device for bottom nozzle and the investigation of the physical phenomena related to CHF enhancement and the establishment of the data base for thermal-hydraulic performance tests has been done in this study. In addition, survey on the documents of the up-to-date PWR fuel assemblies developed by foreign vendors have been carried out to understand their R and D trends and establish the direction of R and D for these structural components. And, to set the performance target of the new fuel, to be developed, fuel burnup and economy under the extended fuel cycle length scheme were estimated. A preliminary study on the failure mechanism of CANDU fuel, key technology and advanced coating has been performed. (author). 190 refs., 31 tabs., 129 figs.
X-Ray Probes of Jupiter's Auroral Zones, Galilean Moons, and the Io Plasma Torus
Elsner, R. F.; Ramsey, B. D.; Swartz, D. A.; Rehak, P.; Waite, J. H., Jr.; Cooper, J. F.; Johnson, R. E.
2005-01-01
Remote observations from the Earth orbiting Chandra X-ray Observatory and the XMM-Newton Observatory have shown the the Jovian system is a rich and complex source of x-ray emission. The planet's auroral zones and its disk are powerful sources of x-ray emission, though with different origins. Chandra observations discovered x-ray emission from the Io plasma torus and from the Galilean moons Io, Europa, and possibly Ganymede. The emission from the moons is due to bombardment of their surfaces by highly energetic magnetospheric protons, and oxygen and sulfur ions, producing fluorescent x-ray emission lines from the elements in their surfaces against an intense background continuum. Although very faint when observed from Earth orbit, an imaging x-ray spectrometer in orbit around the icy Galilean moons would provide a detail mapping of the elemental composition in their surfaces. Here we review the results of Chandra and XMM-Newton observations of the Jovian system and describe the characteristics of X-MIME, an imaging x-ray spectrometer undergoing study for possible application to future missions to Jupiter such as JIMO. X-MIME has the ultimate goal of providing detailed high-resolution maps of the elemental abundances of the surfaces of Jupiter's icy moons and Io, as well as detailed study of the x-ray mission from the Io plasma torus, Jupiter's auroral zones, and the planetary disk.
The Lack of Torus Emission from BL Lacertae Objects: An Infrared View of Unification with WISE
Plotkin, Richard M; Brandt, W N; Markoff, Sera; Shemmer, Ohad; Wu, Jianfeng
2011-01-01
We use data from the Wide-Field Infrared Survey Explorer (WISE) to perform a statistical study on the mid-infrared (IR) properties of a large number ($\\sim10^2$) of BL Lac objects --- low-luminosity Active Galactic Nuclei (AGN) with a jet beamed toward the Earth. As expected, many BL Lac objects are so highly beamed that their jet synchrotron emission dominates their IR spectral energy distributions. In other BL Lac objects, however, the jet is not strong enough to completely dilute the rest of the AGN emission. We do not see observational signatures of the dusty torus from these weakly beamed BL Lac objects. The lack of observable torus emission is consistent with suggestions that BL Lac objects are fed by radiatively inefficient accretion disks. Implications for the "nature vs. nurture" debate for FR I and FR II radio galaxies are briefly discussed. Our study supports the notion that, beyond orientation, accretion rate plays an important role in AGN unification.
International Nuclear Information System (INIS)
This paper discusses the reliability and availability issues in case of two different evacuation system designs which have been proposed for the Next European Torus (NET). One of these designs uses turbo molecular pumps while the other employs cryogenic pumps to evacuate waste products from the torus after every fusion cycle. The aim of this paper is to assess and compare the feasibility of the above two designs form the reliability and availability point of view. A detailed failure mode analysis has been carried out for these two systems and appropriate mathematical mdoels have been developed to calculate their respective reliabilities. Using these mathematical models an extensive parameter study of the system reliability has been carried out over a given range of the component reliabilities. This parameter study shows that the maximum value of the turbo molecular pump system reliability is 96% while the corresponding value for the cryogenic pump system is only 81.6%. The target value for the system availability is 99.9%. This requires that the system mean repair time should be 48 h, appropriate modifications must be made to the turbo pump system design to increase its reliability accordingly. (author). 4 refs.; 10 figs
Topological order and Berry connection for the Maxwell Vacuum on a four-torus
Zhitnitsky, Ariel
2014-01-01
We study novel type of contributions to the partition function of the Maxwell system defined on a small compact manifold such as torus. These new terms can not be described in terms of the physical propagating photons with two transverse polarizations. Rather, these novel contributions emerge as a result of tunnelling events when transitions occur between topologically different but physically identical vacuum winding states. These new terms give an extra contribution to the Casimir pressure. The infrared physics in the system can be described in terms of the topological auxiliary non-propagating fields $a_i(\\mathbf{k})$ governed by Chern-Simons -like action. The system can be studied in terms of these auxiliary fields precisely in the same way as a topological insulator can be analyzed in terms of Berry's connection ${\\cal{A}}_i(\\mathbf{k})$. We also argue that the Maxwell vacuum defined on a small 4-torus behaves very much in the same way as a topological insulator with $\\theta\
Advanced transportation system studies. Alternate propulsion subsystem concepts: Propulsion database
Levack, Daniel
1993-01-01
The Advanced Transportation System Studies alternate propulsion subsystem concepts propulsion database interim report is presented. The objective of the database development task is to produce a propulsion database which is easy to use and modify while also being comprehensive in the level of detail available. The database is to be available on the Macintosh computer system. The task is to extend across all three years of the contract. Consequently, a significant fraction of the effort in this first year of the task was devoted to the development of the database structure to ensure a robust base for the following years' efforts. Nonetheless, significant point design propulsion system descriptions and parametric models were also produced. Each of the two propulsion databases, parametric propulsion database and propulsion system database, are described. The descriptions include a user's guide to each code, write-ups for models used, and sample output. The parametric database has models for LOX/H2 and LOX/RP liquid engines, solid rocket boosters using three different propellants, a hybrid rocket booster, and a NERVA derived nuclear thermal rocket engine.
Conceptual design study of advanced fuel fabrication systems
International Nuclear Information System (INIS)
The fuel fabrication plant images based on the advanced equipment with availability to operate in hot-cell facility are constructed. The characteristics of each fuel fabrication system for economical and environmental are evaluated roughly. The advanced fuel fabrication routes such as simplified pelletizing, vibration compaction and casting process would have the potential for reducing plant construction cost and minimizing the radioactive waste generated from fuel fabrication process. (author)
Analysis of two-torus in a new four-dimensional autonomous system
International Nuclear Information System (INIS)
In this paper, we report the dynamical behaviours of a four-dimensional autonomous continuous dissipative system analysed when the parameter is varied in the range we are interested in. The system changes its dynamical modes between periodic motion and quasiperiodic motion. Furthermore, the existence of two-torus is investigated numerically by means of Lyapunov exponents. By taking advantage of phase portraits and Poincare sections, two types of the two-torus are observed and proved to have the structure of ring torus and horn torus, both of which are known to be the standard tori
Debbi, Latifa
2016-03-01
In this work, we introduce and study the well-posedness of the multidimensional fractional stochastic Navier-Stokes equations on bounded domains and on the torus (briefly dD-FSNSE). For the subcritical regime, we establish thresholds for which a maximal local mild solution exists and satisfies required space and time regularities. We prove that under conditions of Beale-Kato-Majda type, these solutions are global and unique. These conditions are automatically satisfied for the 2D-FSNSE on the torus if the initial data has H 1-regularity and the diffusion term satisfies growth and Lipschitz conditions corresponding to H 1-spaces. The case of 2D-FSNSE on the torus is studied separately. In particular, we established thresholds for the global existence, uniqueness, space and time regularities of the weak (strong in probability) solutions in the subcritical regime. For the general regime, we prove the existence of a martingale solution and we establish the uniqueness under a condition of Serrin's type on the fractional Sobolev spaces.
Study on advancement of in vivo counting using mathematical simulation
Energy Technology Data Exchange (ETDEWEB)
Kinase, Sakae [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment
2003-05-01
To obtain an assessment of the committed effective dose, individual monitoring for the estimation of intakes of radionuclides is required. For individual monitoring of exposure to intakes of radionuclides, direct measurement of radionuclides in the body - in vivo counting- is very useful. To advance in a precision in vivo counting which fulfills the requirements of ICRP 1990 recommendations, some problems, such as the investigation of uncertainties in estimates of body burdens by in vivo counting, and the selection of the way to improve the precision, have been studied. In the present study, a calibration technique for in vivo counting application using Monte Carlo simulation was developed. The advantage of the technique is that counting efficiency can be obtained for various shapes and sizes that are very difficult to change for phantoms. To validate the calibration technique, the response functions and counting efficiencies of a whole-body counter installed in JAERI were evaluated using the simulation and measurements. Consequently, the calculations are in good agreement with the measurements. The method for the determination of counting efficiency curves as a function of energy was developed using the present technique and a physiques correction equation was derived from the relationship between parameters of correction factor and counting efficiencies of the JAERI whole-body counter. The uncertainties in body burdens of {sup 137}Cs estimated with the JAERI whole-body counter were also investigated using the Monte Carlo simulation and measurements. It was found that the uncertainties of body burdens estimated with the whole-body counter are strongly dependent on various sources of uncertainty such as radioactivity distribution within the body and counting statistics. Furthermore, the evaluation method of the peak efficiencies of a Ge semi-conductor detector was developed by Monte Carlo simulation for optimum arrangement of Ge semi-conductor detectors for
Study on advancement of in vivo counting using mathematical simulation
International Nuclear Information System (INIS)
To obtain an assessment of the committed effective dose, individual monitoring for the estimation of intakes of radionuclides is required. For individual monitoring of exposure to intakes of radionuclides, direct measurement of radionuclides in the body - in vivo counting- is very useful. To advance in a precision in vivo counting which fulfills the requirements of ICRP 1990 recommendations, some problems, such as the investigation of uncertainties in estimates of body burdens by in vivo counting, and the selection of the way to improve the precision, have been studied. In the present study, a calibration technique for in vivo counting application using Monte Carlo simulation was developed. The advantage of the technique is that counting efficiency can be obtained for various shapes and sizes that are very difficult to change for phantoms. To validate the calibration technique, the response functions and counting efficiencies of a whole-body counter installed in JAERI were evaluated using the simulation and measurements. Consequently, the calculations are in good agreement with the measurements. The method for the determination of counting efficiency curves as a function of energy was developed using the present technique and a physiques correction equation was derived from the relationship between parameters of correction factor and counting efficiencies of the JAERI whole-body counter. The uncertainties in body burdens of 137Cs estimated with the JAERI whole-body counter were also investigated using the Monte Carlo simulation and measurements. It was found that the uncertainties of body burdens estimated with the whole-body counter are strongly dependent on various sources of uncertainty such as radioactivity distribution within the body and counting statistics. Furthermore, the evaluation method of the peak efficiencies of a Ge semi-conductor detector was developed by Monte Carlo simulation for optimum arrangement of Ge semi-conductor detectors for designing a
Field study of disposed solid wastes from advanced coal processes
International Nuclear Information System (INIS)
Radian Corporation and the North Dakota Energy and Environmental Research Center (EERC) are funded to develop information to be used by private industry and government agencies for managing solid wastes produced by advanced coal combustion processes. This information will be developed by conducting several field studies on disposed wastes from these processes. Data will be collected to characterize these wastes and their interactions with the environments in which they are disposed. Three sites were selected for the field studies: Colorado Ute's fluidized bed combustion (FBC) unit in Nucla, Colorado; Ohio Edison's limestone injection multistage burner (LIMB) retrofit in Lorain, Ohio; and Freeman United's mine site in central Illinois with wastes supplied by the nearby Midwest Grain FBC unit. During the past year, field monitoring and sampling of the four landfill test cases constructed in 1989 and 1991 has continued. Option 1 of the contract was approved last year to add financing for the fifth test case at the Freeman United site. The construction of the Test Case 5 cells is scheduled to begin in November, 1992. Work during this past year has focused on obtaining data on the physical and chemical properties of the landfilled wastes, and on developing a conceptual framework for interpreting this information. Results to date indicate that hydration reactions within the landfilled wastes have had a major impact on the physical and chemical properties of the materials but these reactions largely ceased after the first year, and physical properties have changed little since then. Conditions in Colorado remained dry and no porewater samples were collected. In Ohio, hydration reactions and increases in the moisture content of the waste tied up much of the water initially infiltrating the test cells
Orbital transfer rocket engine technology: Advanced engine study
Hayden, Warren R.
1992-01-01
An advanced LOX/LH2 engine study for the use of NASA and vehicle prime contractors in developing concepts for manned missions to the Moon, Mars, and Phobos is documented. Parametric design data was obtained at five engine thrusts from 7.5K lbf to 50K lbf. Also, a separate task evaluated engine throttling over a 20:1 range and operation at a mixture ratio of 12 plus or minus 1 versus the 6 plus or minus 1 nominal. Cost data was also generated for DDT&E, first unit production, and factors in other life cycle costs. The major limitation of the study was lack of contact with vehicle prime contractors to resolve the issues in vehicle/engine interfaces. The baseline Aerojet dual propellant expander cycle was shown capable of meeting all performance requirements with an expected long operational life due to the high thermal margins. The basic engine design readily accommodated the 20:1 throttling requirement and operation up to a mixture ratio of 10 without change. By using platinum for baffled injector construction the increased thermal margin allowed operation up to mixture ratio 13. An initial engine modeling with an Aerojet transient simulation code (named MLETS) indicates stable engine operation with the baseline control system. A throttle ratio of 4 to 5 seconds from 10 percent to 100 percent thrust is also predicted. Performance predictions are 483.1 sec at 7.5K lbf, 487.3 sec at 20K lbf, and 485.2 sec at 50K lbf with a mixture ratio of 6 and an area ratio of 1200. Engine envelopes varied from 120 in. length/53 in. exit diameter at 7.5K lbf to 305 in. length/136 in. exit diameter at 50 K lbf. Packaging will be an important consideration. Continued work is recommended to include more vehicle prime contractor/engine contractor joint assessment of the interface issues.
Bisbas, T G; Barlow, M J; Viti, S; Harries, T J; Bell, T; Yates, J A
2015-01-01
The interaction of ionizing and far-ultraviolet radiation with the interstellar medium is of great importance. It results in the formation of regions in which the gas is ionized, beyond which are photodissociation regions (PDRs) in which the gas transitions to its atomic and molecular form. Several numerical codes have been implemented to study these two main phases of the interstellar medium either dynamically or chemically. In this paper we present TORUS-3DPDR, a new self-consistent code for treating the chemistry of three-dimensional photoionization and photodissociation regions. It is an integrated code coupling the two codes TORUS, a hydrodynamics and Monte Carlo radiation transport code, and 3D-PDR, a photodissociation regions code. The new code uses a Monte Carlo radiative transfer scheme to account for the propagation of the ionizing radiation including the diffusive component as well as a ray-tracing scheme based on the HEALPix package in order to account for the escape probability and column density...
The Impact of the Dusty Torus on Obscured Quasar Halo Mass Measurements
DiPompeo, Michael A; Hickox, Ryan C; Myers, Adam D; Geach, James E
2016-01-01
Recent studies have found that obscured quasars cluster more strongly and are thus hosted by dark matter haloes of larger mass than their unobscured counterparts. These results pose a challenge for the simplest unification models, in which obscured objects are intrinsically the same as unobscured sources but seen through a dusty line of sight. There is general consensus that a structure like a "dusty torus" exists, meaning that this intrinsic similarity is likely the case for at least some subset of obscured quasars. However, the larger host halo masses of obscured quasars implies that there is a second obscured population that has an even higher clustering amplitude and typical halo mass. Here, we use simple assumptions about the host halo mass distributions of quasars, along with analytical methods and cosmological $N$-body simulations to isolate the signal from this population. We provide values for the bias and halo mass as a function of the fraction of the "non-torus obscured" population. Adopting a reas...
Coherent state wave functions on a torus with a constant magnetic field
International Nuclear Information System (INIS)
We study two alternative definitions of localized states in the lowest Landau level (LLL) on a torus. One definition is to construct localized states, as the projection of the coordinate delta function onto the LLL. Another definition, proposed by Haldane, is to consider the set of functions which have all their zeros at a single point. Since a LLL wave function on a torus, supporting Nϕ magnetic flux quanta, is uniquely defined by the position of its Nϕ zeros, this defines a set of functions that are expected to be localized around the point maximally far away from the zeros. These two families of localized states have many properties in common with the coherent states on the plane and on the sphere, viz a resolution of unity and a self-reproducing kernel. However, we show that only the projected delta function is maximally localized. Additionally, we show how to project onto the LLL, functions that contain holomorphic derivatives and/or anti-holomorphic polynomials, and apply our methods in the description of hierarchical quantum Hall liquids. (paper)
National Spherical Torus Experiment: engineering overview and research results 1999-2000
International Nuclear Information System (INIS)
The National Spherical Torus Experiment (NSTX) is a new US facility for the study of plasma confinement, heating, and current drive in a low aspect ratio, spherical torus (ST) configuration. The ST configuration is an alternate magnetic confinement concept which is characterized by high β (ratio plasma pressure to magnetic field pressure) and low toroidal field compared to conventional tokamaks, and could provide a pathway to the realization of a practical fusion power source. NSTX achieved first plasma in February 1999, and since that time has completed and commissioned all components and systems within the machine proper. Routine operation with inductively driven plasma current ≤1 MA and flat top ≤0.3 s has been established, and the ohmic characterization phase of the research program is underway. Radio frequency (RF) and neutral beam injection (NBI) systems have been installed and are presently being commissioned. This paper describes the NSTX mission, gives an overview of the engineering design, and summarizes the research results obtained thus far
Conformal perturbation theory and higher spin entanglement entropy on the torus
Datta, Shouvik; David, Justin R.; Kumar, S. Prem
2015-04-01
We study the free fermion theory in 1+1 dimensions deformed by chemical potentials for holomorphic, conserved currents at finite temperature and on a spatial circle. For a spin-three chemical potential μ, the deformation is related at high temperatures to a higher spin black hole in hs[0] theory on AdS3 spacetime. We calculate the order μ 2 corrections to the single interval Rényi and entanglement entropies on the torus using the bosonized formulation. A consistent result, satisfying all checks, emerges upon carefully accounting for both perturbative and winding mode contributions in the bosonized language. The order μ 2 corrections involve integrals that are finite but potentially sensitive to contact term singularities. We propose and apply a prescription for defining such integrals which matches the Hamiltonian picture and passes several non-trivial checks for both thermal corrections and the Rényi entropies at this order. The thermal corrections are given by a weight six quasi-modular form, whilst the Rényi entropies are controlled by quasi-elliptic functions of the interval length with modular weight six. We also point out the well known connection between the perturbative expansion of the partition function in powers of the spin-three chemical potential and the Gross-Taylor genus expansion of large- N Yang-Mills theory on the torus. We note the absence of winding mode contributions in this connection, which suggests qualitatively different entanglement entropies for the two systems.
From horizon to torus: Uncovering supermassive black hole systems
Murphy, Kendrah
2009-06-01
The complexity of the structure and behavior of AGNs is often imprinted in the Fe K line emission in their X-ray spectra. We present a study of the Seyfert galaxy NGC 2992 with RXTE and Suzaku , which highlights this complexity, as we find evidence of both persistent emission from the accretion disk and from matter more distant from the central black hole (i.e., the putative obscuring torus), as well as short-term flaring emission from the accretion disk. Future X-ray instrumentation is expected to allow us to significantly improve the constraints derived from the Fe K lines in AGN, such as the black-hole angular momentum (spin) and the inclination angle of the putative accretion disk. However, significant model-dependence and degeneracy will persist with radially-integrated Fe K line profiles, so we have investigated the feasibility of utilizing Fe K line emission from localized orbiting flares ("hotspots") to provide a more robust measure of black-hole spin. In addition to affecting the persistent and transient Fe K line emission, the physical structure, geometry, and orientation of the central engine harboring the black hole furthermore effect the observed continuum in specific ways. It is therefore necessary to self-consistently model the continuum and emission lines in order to derive constraints on the physical parameters of the system. Improved X-ray spectral data quality has facilitated the ability to disentangle some of the spectral components, but the increased spectral complexity creates a need for more sophisticated models. Such a need has arisen with respect to the X-ray spectra of obscured AGN. To that end, we describe a new X-ray spectral model, based on Monte-Carlo simulations of the toroidal reprocessor, that will allow one to self-consistently fit for the line emission from distant matter as well as the associated Compton-scattered continuum. The model is valid for arbitrary incident spectra and can therefore be combined with models of
Energy Technology Data Exchange (ETDEWEB)
Janiuk, Agnieszka; Mioduszewski, Patryk [Center for Theoretical Physics, Polish Academy of Sciences, Al. Lotnikow 32/46, 02-668 Warsaw (Poland); Moscibrodzka, Monika, E-mail: agnes@cft.edu.pl [Department of Physics, University of Nevada Las Vegas, 4505 South Maryland Parkway, Las Vegas, NV 89154 (United States)
2013-10-20
We calculate the structure and short-term evolution of a gamma-ray burst (GRB) central engine in the form of a turbulent torus accreting onto a stellar mass black hole. Our models apply to the short GRB events, in which a remnant torus forms after the neutron star-black hole or a double neutron star merger and is subsequently accreted. We study the two-dimensional, relativistic models and concentrate on the effects of the black hole and flow parameters as well as the neutrino cooling. We compare the resulting structure and neutrino emission to the results of our previous one-dimensional simulations. We find that the neutrino cooled torus launches a powerful mass outflow, which contributes to the total neutrino luminosity and mass loss from the system. The neutrino luminosity may exceed the Blandford-Znajek luminosity of the polar jets and the subsequent annihilation of neutrino-antineutrino pairs will provide an additional source of power to the GRB emission.
Directory of Open Access Journals (Sweden)
Chunbao Liu
2015-01-01
Full Text Available Passenger car torque converters have been designed with an increasingly flatter profile in recent years for the purpose of achieving a weight saving and more compact size. However, a flatter design tends to result in the reduced hydrodynamic performance. To improve its performance, a new flat torus of elliptic type method concentrating on the solution to flat TC was put forward, and four torque converters of different flatness ratios were designed to judge the superiority of the flat torus design method. The internal flow characteristics were numerically investigated using CFD codes and resulted in good agreement with experimental data. The results indicate that the main cause of this performance degradation can be attributed to deterioration of the velocity fields of the pump, and a case of flatness ratio 0.8 illustrates the reason that the performance designed by the flat torus design method based on the elliptic shape is more excellent than that of the traditional one. Furthermore, this study proposed a structure of removal of inner ring to improve the performance of torque converter.
International Nuclear Information System (INIS)
We calculate the structure and short-term evolution of a gamma-ray burst (GRB) central engine in the form of a turbulent torus accreting onto a stellar mass black hole. Our models apply to the short GRB events, in which a remnant torus forms after the neutron star-black hole or a double neutron star merger and is subsequently accreted. We study the two-dimensional, relativistic models and concentrate on the effects of the black hole and flow parameters as well as the neutrino cooling. We compare the resulting structure and neutrino emission to the results of our previous one-dimensional simulations. We find that the neutrino cooled torus launches a powerful mass outflow, which contributes to the total neutrino luminosity and mass loss from the system. The neutrino luminosity may exceed the Blandford-Znajek luminosity of the polar jets and the subsequent annihilation of neutrino-antineutrino pairs will provide an additional source of power to the GRB emission
Birmingham, T. J.; Alexander, J. K.; Desch, M. D.; Hubbard, R. F.; Pedersen, B. M.
1980-01-01
Narrow-banded emissions were observed by the Planetary Radio Astronomy experiment on the Voyager 1 spacecraft as it traversed the Io plasma torus. These waves occur between harmonics of the electron gyrofrequency and are the Jovian analogue of electrostatic emissions observed and theoretically studied for the terrestrial magnetosphere. The observed frequencies always include the component near the upper hybrid resonant frequency, (fuhr) but the distribution of the other observed emissions varies in a systematic way with position in the torus. A refined model of the electron density variation, based on identification of the fuhr line, is included. Spectra of the observed waves are analyzed in terms of the linear instability of an electron distribution function consisting of isotropic cold electrons and hot losscone electrons. The positioning of the observed auxiliary harmonics with respect to fuhr is shown to be an indicator of the cold to hot temperature ratio. It is concluded that this ratio increases systematically by an overall factor of perhaps 4 or 5 between the inner and outer portions of the torus.
Advanced processes for minor actinides recycling: studies towards potential industrialization
International Nuclear Information System (INIS)
In June 2006, a new act on sustainable management of radioactive waste was voted by the French parliament with a national plan on radioactive materials and radioactive waste management (PNG-MDR). Concerning partitioning and transmutation, the program is connected to 4. generation reactors, in which transmutation of minor actinides could be operated. In this frame, the next important milestone is 2012, with the assessment of the possible transmutation roads, which are either homogeneous recycling of the minor actinides in the whole reactor fleet, with a low content of M.A (∼3%) in all fuel assemblies, or heterogeneous recycling of the minor actinides in about one third of the reactor park, with a higher content of M.A. (∼20%) in dedicated targets dispatched in the periphery of the reactor. Advanced processes for the recycling of minor actinides are being developed to address the challenges of these various management options. An important part of the program consists in getting closer to process implementation conditions. The processes based on liquid-liquid extraction benefit from the experience gained by operating the PUREX process at the La Hague plant. In the field of extracting apparatus, a large experience is available. In the field of extracting apparatus, a large experience is already available. Nevertheless, the processes present specificities which have to be considered more precisely. They have been classified in the following fields: - Evolution of the simulation codes, including phenomenological representations: with such a simulation tool, it will be possible to assess operating tolerances, lead sensitivity studies and calculate transient states; - Definition of the implementation conditions in continuous contactors (such as pulse columns), according to the extractant physico-chemical characteristics; - Scale-up of new extractants, such as malonamides used in the DIAMEX process, facing purity specifications and costs estimation; - Solvent clean
International Nuclear Information System (INIS)
Highlights: • Plasma disruption mitigation by massive gas injection and consequences on the torus vacuum system are discussed. • The temperature of the torus primary vacuum cryogenic pumps is increasing significantly after massive gas injection events. • The injected quantities of neon and argon can be efficiently processed by the torus primary vacuum cryogenic pumps. • The large injected quantities of deuterium and helium have to be processed by the rough and regeneration pumping system. • The torus vacuum system turnover time is shorter after neon or argon injections than after deuterium or helium injections. - Abstract: The ITER torus exhaust pumping system is based on six primary vacuum cryogenic pumps, and a rough and regeneration pumping system that can pump the exhaust gases from the torus cryopumps to the tritium plant. Massive gas injection is a proposed concept to mitigate plasma disruptions in ITER. The present paper identifies the limitations and down-times of the ITER torus pumping system after a massive gas injection event. Deuterium, helium, neon, and argon injections are discussed. The resulting high pressure in the torus is leading to high mass flows and heat fluxes to the cryogenic pumps, resulting in a significant and rapid temperature increase of the pumping surfaces normally cooled at 5 K. However, the consequences on the torus pumping system operation depend on the gas species and quantities injected. Finally, the regeneration of the cryopumps, the rough pumping of the torus, and the overall torus pumping system turnover time until vacuum and thermal conditions for the start of the next plasma pulse are initiated again are discussed
Jalnine, A.; Osbaldestin, Andrew
2005-01-01
A transition from a smooth torus to a chaotic attractor in quasiperiodically forced dissipative systems may occur after a finite number of torus-doubling bifurcations. In this paper we investigate the underlying bifurcational mechanism, which is responsible for the termination of the torus-doubling cascades on the routes to chaos in invertible maps under external quasiperiodic forcing. We consider the structure in the vicinity of a smooth attracting invariant curve (torus) in the quasiperiodi...
Recent Advances in Studies of Coastal Marsh Sedimentation
Pasternack, G. B.; Leonard, L. A.
2001-05-01
Limited understanding of sedimentation processes in coastal marshes is a key constraint on the management of environmental impacts associated with sea level rise, degrading quality and quantity of aquatic habitats, and downstream impacts of watershed land use. The problem is exacerbated by complex interactions among physical, ecological, and chemical variables that impact sedimentation over a large range of spatio-temporal scales. These challenges are being met by increasingly sophisticated approaches which cross-fertilize from other disciplines or go even further to integrate multidisciplinary perspectives. One example of the former has been improved precision of fine scale measurements of fluid mechanics and sediment transport over marsh plains and application of those measurements in geomorphologic and coastal engineering models. This advancement has improved our understanding of marsh dynamics at a mechanistic level, which is key for improving the predictive capabilities of wetland models. An example of a multidisciplinary approach that has become very common is the combined usage of multiple monitoring, isotopic, and palynological methods for estimating sedimentation and erosion at a site over a range of time scales. By applying such combinations, it has been possible to piece apart the relative roles of natural processes such as sea level rise and storms from human impacts such as flow constrictions, channel dredging, and sediment supply changes. Beyond improving approaches used to study marshes, past work has led to new questions about marsh morphodynamics and how coastal marshes interact with upland watersheds. With the aid of chaos theory, some recent studies have asserted that coastal marsh channels are fractal and thus must follow universal laws in common with watershed drainages and other dendritic systems. Also, where marshes exist among a mosaic of habitats on a delta, research has revealed the relative roles of watershed versus coastal processes in
The J.E.T (Joint European Torus) vacuum vessel
International Nuclear Information System (INIS)
The large vacuum vessel of the J.E.T. (Joint European Torus) experiment has been designed as an all metal composite torus of non-circular cross-section. To comply with mechanical stability and ultra high vacuum requirements it has been designed as a completely welded fabrication. The metal structure consists of 32 rigid sectors of box type construction suitably ribbed to withstand the stresses imposed upon them by the external forces. The bellows linking these rigid sectors determine the electrical resistance of the metallic vacuum vessel the long way around the torus, since currents which are induced in parallel with the plasma current should be kept as low as possible. All forces acting on the vacuum vessel are absorbed by the rigid sectors which also incorporate the openings to the interior of the machine, such as ports for pumping, diagnostics, auxiliary plasma heating, etc... This toroidal vacuum vessel is a double walled structure with the bellows linking the rigid sectors being fitted as pairs, and it is proposed to circulate hot inert gas through out this interspace in order to raise the temperature of the whole vacuum vessel to 500 degres C to achieve bakeout conditions which will assist in reaching the required base pressure of 10-10 torr, the outside of the vacuum vessel will be thermally insulated. The final choice of materials to construct this vacuum vessel was to use Inconel 600 or Nicrofer 7216 for the rigid sectors and Inconel 625 (Nicrofer 6020) for the bellows, the latter material having the required electrical resistivity
Reflectometry and transport in thermonuclear plasmas in the Joint European Torus
International Nuclear Information System (INIS)
The subjects of this thesis are the study of microwave reflectometry as a method to measure electron density profiles, and the study of particle and energy transport in thermonuclear plasmas. In the transport studies data of a 12-channel reflectometer system are used to analyze the propagation of electron density perturbations in the plasma. The measurements described in this thesis are performed in the plasmas in the Joint European Torus (JET). The main points of study described are based on microwave reflectometry, the principles of which are given. Two modes of operation of a reflectometer are described. Firstly, electro-magnetic waves with constant frequencies may be launched into the plasma to measure variations in the electron density profile. Secondly, the absolute density profile can be measured with a reflectometer, when the source frequencies are swept. (author). 56 refs.; 41 figs.; 5 tabs
Readability of state-sponsored advance directive forms in the United States: a cross sectional study
Mueller Paul S; Reid Kevin I; Mueller Luke A
2010-01-01
Abstract Background State governments provide preprinted advance directive forms to the general public. However, many adults in the United States (US) lack the skills necessary to read and comprehend health care-related materials. In this study, we sought to determine the readability of state government-sponsored advance directive forms. Methods A cross sectional study design was used. The readability of advance directive forms available online from all 50 US states and the District of Columb...
Jet and Torus Orientations in High Redshift Radio Galaxies
Drouart, G; Vernet, J; Laing, R A; Seymour, N; Stern, D; Haas, M; Pier, E A; Rocca-Volmerange, B
2012-01-01
We examine the relative orientation of radio jets and dusty tori surrounding the AGN in powerful radio galaxies at z > 1. The radio core dominance R = P(20 GHz) /P(500 MHz) serves as an orientation indicator, measuring the ratio between the anisotropic Doppler-beamed core extended core emission and the isotropic lobe emission. Assuming a fixed cylindrical geometry for the hot, dusty torus, we derive its inclination i by fitting optically-thick radiative transfer models to spectral energy distributions obtained with the Spitzer Space Telescope. We find a highly significant anti-correlation (p 1.3.
On the dynamics of tilted black hole-torus systems
Mewes, V.; Galeazzi, F.; Font, J; Montero, P.; Stergioulas, N.
2016-01-01
We present results from three-dimensional, numerical relativity simulations of a tilted black hole-thick accretion disc system. The simulations are analysed using tracer particles in the disc which are advected with the flow. Such tracers, which we employ in these new simulations for the first time, provide a powerful means to analyse in detail the complex dynamics of tilted black hole-torus systems. We show how its use helps to gain insight in the overall dynamics of the system, discussing t...
Fascinating relation between torus knot and accelerator lattice
International Nuclear Information System (INIS)
We propose a new scheme of lattice design for a compact storage ring in which a design orbit closes after completing multiple turns. The lattice of this type can be realized by placing bending magnets, quadrupole magnets, and other necessary accelerator components on a projected torus knot in the horizontal orbit plane. The ring with this type of lattice may have larger maximum stored charge if operated in multiple-bunch mode, and longer bunch-to-bunch interval if operated in a single-bunch mode. Also, for an electron storage ring as the synchrotron light source, a larger number of straight sections may accommodate with many insertion devices. (author)
Exact solution of an su(n) spin torus
Hao, Kun; Cao, Junpeng; Li, Guang-Liang; Yang, Wen-Li; Shi, Kangjie; Wang, Yupeng
2016-07-01
The trigonometric su(n) spin chain with anti-periodic boundary condition (su(n) spin torus) is demonstrated to be Yang–Baxter integrable. Based on some intrinsic properties of the R-matrix, certain operator product identities of the transfer matrix are derived. These identities and the asymptotic behavior of the transfer matrix together allow us to obtain the exact eigenvalues in terms of an inhomogeneous T ‑ Q relation via the off-diagonal Bethe Ansatz.
Invariant sets for discontinuous parabolic area-preserving torus maps
Ashwin, P; Nishikawa, T; Zyczkowski, K; Ashwin, Peter; Fu, Xin-Chu; Nishikawa, Takashi; Zyczkowski, Karol
1999-01-01
We analyze a class of piecewise linear parabolic maps on the torus, namely those obtained by considering a linear map with double eigenvalue one and taking modulo one in both components. We show that within this two parameter family of maps, the set of noninvertible maps is open and dense. For certain cases (where the entries in the matrix are rational) we show that the maximal invariant set has positive Lebesgue measure and give bounds on the measure. For certain examples we find expressions for the measure of the invariant set.
Fourier Modeling of the Radio Torus Surrounding Supernova 1987A
Ng, C. -Y.; Gaensler, B. M.; Staveley-Smith, L.; Manchester, R. N.; Kesteven, M. J.; BALL, L; Tzioumis, A. K.
2008-01-01
We present detailed Fourier modeling of the radio remnant of Supernova 1987A, using high-resolution 9 GHz and 18 GHz data taken with the Australia Telescope Compact Array over the period 1992 to 2008. We develop a parameterized three-dimensional torus model for the expanding radio shell, in which the emission is confined to an inclined equatorial belt; our model also incorporates both a correction for light travel-time effects and an overall east-west gradient in the radio emissivity. By deri...
The p-adic string compactified on a torus
International Nuclear Information System (INIS)
The open p-adic string world sheet is a coset space F=T/Γ, where T is the Bruhat-Tits tree for the p-adic linear group GL(2,Qp) and Γ is contained in PGL(2,Qp) is some Schottky group. The boundary of this world sheet corresponds to a p-adic Mumford curve of finite genus. The string dynamics is governed by the local action on F, with the fields taking values in a compact group G. We find the correlation functions and partition functions for the curves of arbitrary genus and G=U(1)xD (D-dimensional torus). (author). 21 refs
Implementation of BN Control in the National Spherical Torus Experiment
Energy Technology Data Exchange (ETDEWEB)
Gerhardt, S; Bell, M G; Cropper, M; Gates, D A; Koleman, E; Lawson, J; Marsala, B; Menard, J E; Mueller, D
2012-09-15
We have designed and constructed a system for control of the normalized B in the National Spherical Torus Experiment [M. Ono, et al., Nuclear Fusion 40, 557 (2000)]. A PID operator is applied to the difference between the present value of B N (from realtime equilibrium reconstruction) and a time-dependent request, in order to calculate the required injected power. This injected power request is then turned into modulations of the neutral beams. The details of this algorithm are described, including the techniques used to develop the appropriate control gains. Example uses of the system are shown
Final report on the LLNL compact torus acceleration project
International Nuclear Information System (INIS)
In this report, we summarize recent work at LLNL on the compact torus (CT) acceleration project. The CT accelerator is a novel technique for projecting plasmas to high velocities and reaching high energy density states. The accelerator exploits magnetic confinement in the CT to stably transport plasma over large distances and to directed kinetic energies large in comparison with the CT internal and magnetic energy. Applications range from heating and fueling magnetic fusion devices, generation of intense pulses of x-rays or neutrons for weapons effects and high energy-density fusion concepts
The Picard Group of a Noncommutative Algebraic Torus
Berest, Yuri; Ramadoss, Ajay; Tang, Xiang
2010-01-01
We compute the Picard group $ Pic(A_q) $ of the noncommutative algebraic 2-torus $A_q$, describe its action on the space $ R(A_q) $ of isomorphism classes of rk 1 projective modules and classify the algebras Morita equivalent to $ A_q $. Our computations are based on a quantum version of the Calogero-Moser correspondence relating projective $A_q$-modules to irreducible representations of the double affine Hecke algebras (DAHA) $ H_{t, q^{-1/2}}(S_n) $ at $ t = 1 $. We show that, under this co...
Casimir Energies on a Twisted Two-Torus
Institute of Scientific and Technical Information of China (English)
程红波; 李新洲
2001-01-01
We consider a twisted massless multiplet on a two-torus, one side with a normal boundary and the other with a twisted boundary. The Casimir energy is calculated and regularized by means of the Epstein-Hurwitz-type zeta-function introduced by Elizalde. The resulting dimensions of spacetime for the twisted case may be integers.The results are compared with those of the untwisted case. Since twisted Casimir energy is lower than untwisted energy, the untwisted case may change into the twisted state in the spacetime.
Construction of an A-manifold on a principal torus bundle
Directory of Open Access Journals (Sweden)
Grzegorz Zborowski
2013-02-01
Full Text Available We construct a new example of an A-manifold, i.e. a Riemannian manifold with cyclic-parallel Ricci tensor. This condition can be viewed as a generalization of the Einstein condition. The underlying manifold for our construction is a principal torus bundle over Kähler-Einstein manifold with fibre a torus of arbitrary dimension.
Construction of an A-manifold on a principal torus bundle
Grzegorz Zborowski
2012-01-01
We construct a new example of an A-manifold, i.e. a Riemannian manifold with cyclic-parallel Ricci tensor. This condition can be viewed as a generalization of the Einstein condition. The underlying manifold for our construction is a principal torus bundle over Kähler-Einstein manifold with fibre a torus of arbitrary dimension.
On the fundamental group of the complement of linear torus curves of maximal contact
Kawashima, M.
2010-01-01
In this paper, we compute the fundamental group of the complement of linear torus curves of maximal contact and we show that it is isomorphic to that of generic linear torus curves. As an application, we give new two Zariski triples.
On the existence of star products on quotient spaces of linear Hamiltonian torus actions
DEFF Research Database (Denmark)
Herbig, Hans-Christian; Iyengar, Srikanth B.; Pflaum, Markus J.
2009-01-01
Koszul complex on the moment map of an effective linear Hamiltonian torus action is acyclic. We rephrase the nonpositivity condition of Arms and Gotay (Adv Math 79(1):43–103, 1990) for linear Hamiltonian torus actions. It follows that reduced spaces of such actions admit continuous star products....
Christophorou, L; Luessen, L
1988-01-01
As the various disciplines of science advance, they proliferate and tend to become more esoteric. Barriers of specialized terminologies form, which cause scientists to lose contact with their colleagues, and differences in points-of-view emerge which hinder the unification of knowledge among the various disciplines, and even within a given discipline. As a result, the scientist, and especially the student, is in many instances offered fragmented glimpses of subjects that are funda mentally synthetic and that should be treated in their own right. Such seems to be the case of the liquid state. Unlike the other states of matter -- gases, solids, and plasmas -- the liquid state has not yet received unified treatment, probably because it has been the least explored and remains the least understood state of matter. Occasionally, events occur which help remove some of the barriers that separate scientists and disciplines alike. Such an event was the ASI on The Liquid State held this past July at the lovely Hotel T...
Conceptual design study: Forest Fire Advanced System Technology (FFAST)
Nichols, J. D.; Warren, J. R.
1986-01-01
An integrated forest fire detection and mapping system that will be based upon technology available in the 1990s was defined. Uncertainties in emerging and advanced technologies related to the conceptual design were identified and recommended for inclusion as preferred system components. System component technologies identified for an end-to-end system include thermal infrared, linear array detectors, automatic georeferencing and signal processing, geosynchronous satellite communication links, and advanced data integration and display. Potential system configuration options were developed and examined for possible inclusion in the preferred system configuration. The preferred system configuration will provide increased performance and be cost effective over the system currently in use. Forest fire management user requirements and the system component emerging technologies were the basis for the system configuration design. A preferred system configuration was defined that warrants continued refinement and development, examined economic aspects of the current and preferred system, and provided preliminary cost estimates for follow-on system prototype development.
Renewable Energy Laboratory Development for Biofuels Advanced Combustion Studies
Energy Technology Data Exchange (ETDEWEB)
Soloiu, Valentin [Georgia Southern Univ., Statesboro, GA (United States)
2012-03-31
The research advanced fundamental science and applied engineering for increasing the efficiency of internal combustion engines and meeting emissions regulations with biofuels. The project developed a laboratory with new experiments and allowed investigation of new fuels and their combustion and emissions. This project supports a sustainable domestic biofuels and automotive industry creating economic opportunities across the nation, reducing the dependence on foreign oil, and enhancing U.S. energy security. The one year period of research developed fundamental knowledge and applied technology in advanced combustion, emissions and biofuels formulation to increase vehicle's efficiency. Biofuels combustion was investigated in a Compression Ignition Direct Injection (DI) to develop idling strategies with biofuels and an Indirect Diesel Injection (IDI) intended for auxiliary power unit.
Experimental study of an advanced silica gel dehumidifier
Energy Technology Data Exchange (ETDEWEB)
Bharathan, D.; Parsons, J.M.; Maclaine-cross, I.L.
1987-11-01
This report contains results of work done to experimentally characterize the performance of an advanced, rotary, desiccant dehumidifier and to develop and validate analytical methods for evaluating its performance in air-conditioning systems. A facility, the Cyclic Test Facility, and a test and analysis procedure were developed to evaluate the performance of the dehumidifier. A series of tests was undertaken to understand the simultaneous heat- and mass-transfer processes. An advanced dehumidifier test article was tested under cyclic operation to fully characterize its performance. Brief accounts of this facility, with its hardware and instrumentation, and detailed accounts of the test data and data reduction and analysis methods are presented. The data provide an engineering data base for evaluating rotary dehumidifiers for cooling applications. The dehumidifier's performance, as measured by the effectiveness, agreed with theory to within plus or minus 10%. 16 refs., 16 figs., 1 tab.
Study of Advanced Oxidation System for Water Treatment
International Nuclear Information System (INIS)
Hygiene water is still a big problem globally as well as energy and food, especially in Indonesia where more than 70 % lived in Java island. One of the efforts in treating hygiene water is to recycle the used water. In this case it is needed clean water technology. Many methods have been done, this paper describes the advanced oxidation technology system based on ozone, titania and plasma discharge. (author)
Advances in the study of hybrid finite elements
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
Some new concepts and research progress in hybrid finite elements advanced in recent years are in troduced. On the basis of incompatible energy consistency analysis, the optimal condition of hybrid elements is derived and the formulation for fulfilling this condition is given. A post-processing penalty equilibrium optimization technique of hybrid element is presented to create high quality hybrid model. For incompressible problems, a method of deviatoric hybrid element is proposed and unification of computation between compressible and incompressible media is achieved.
Superconformal index and 3d-3d correspondence for mapping cylinder/torus
International Nuclear Information System (INIS)
We probe the 3d-3d correspondence for mapping cylinder/torus using the superconformal index. We focus on the case when the fiber is a once-punctured torus (Σ1,1). The corresponding 3d field theories can be realized using duality domain wall theories in 4d N=2∗ theory. We show that the superconformal indices of the 3d theories are the SL(2,ℂ) Chern-Simons partition function on the mapping cylinder/torus. For the mapping torus, we also consider another realization of the corresponding 3d theory associated with ideal triangulation. The equality between the indices from the two descriptions for the mapping torus theory is reduced to a simple basis change of the Hilbert space for the SL(2,ℂ) Chern-Simons theory on ℝ×Σ1,1
Induction effects of torus knots and unknots
Oberti,
2015-01-01
In questa tesi si analizzano gli effetti di induzione di un campo sorgente stazionario nella forma di un filamento a nodo o non-nodo torico. Studi simili sono stati compiuti per geometrie rettilinee, circolari o elicoidali, ma poco o nulla è noto per geometrie e topologie più complesse. I nodi torici sono un raro esempio di curve spaziali chiuse con topologia non banale che ammettono una descrizione matematicamente semplice; per questo rappresentano un interessante caso da studiare. Inoltre, ...
Performance of a 12-coil superconducting bumpy torus magnet facility
Roth, J. R.; Holmes, A. D.; Keller, T. A.; Krawczonek, W. M.
1972-01-01
The bumpy torus facility consists of 12 superconducting coils, each 19 cm i.d. and capable of 3.0 teslas on their axes. The coils are equally spaced around a toroidal array with a major diameter of 1.52 m, and are mounted with the major axis of the torus vertical in a single vacuum tank 2.6 m in diameter. Final shakedown tests of the facility mapped out its magnetic, cryogenic, vacuum, mechanical, and electrical performance. The facility is now ready for use as a plasma physics research facility. A maximum magnetic field on the magnetic axis of 3.23 teslas was held for a period of more than sixty minutes without a coil normalcy. The design field was 3.00 teslas. The steady-state liquid helium boil-off rate was 87 liters per hour of liquid helium without the coils charged. The coil array was stable when subjected to an impulsive loading, even with the magnets fully charged. When the coils were charged to a maximum magnetic field of 3.35 teslas, the system was driven normal without damage.