WHISTBT: a 1-1/2-D radial-transport code for bumpy tori
The computer code WHISTBT has been developed from the Oak Ridge National Laboratory WHIST code to study radial transport in bumpy tori. The code can handle both positive and negative ad hoc electric fields for devices ranging from the size of ELMO Bumpy Torus-Scale (EBT-S) to a reactor-type device, EBT-R. Fueling can be by gas puffing or pellets; heating can be by injection of rf power or neutral beams
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.
The ELMO Bumpy Square (EBS) concept consists of four straight magnetic mirror arrays linked by four high-field corner coils. Extensive calculations show that this configuration offers major improvements over the ELMO Bumpy Torus (EBT) in particle confinement, heating, transport, ring production, and stability. The components of the EBT device at Oak Ridge National Laboratory can be reconfigured into a square arrangement having straight sides composed of EBT coils, with new microwave cavities and high-field corners designed and built for this application. The elimination of neoclassical convection, identified as the dominant mechanism for the limited confinement in EBT, will give the EBS device substantially improved confinement and the flexibility to explore the concepts that produce this improvement. The primary goals of the EBS program are twofold: first, to improve the physics of confinement in toroidal systems by developing the concepts of plasma stabilization using the effects of energetic electrons and confinement optimization using magnetic field shaping and electrostatic potential control to limit particle drift, and second, to develop bumpy toroid devices as attractive candidates for fusion reactors. This report presents a brief review of the physics analyses that support the EBS concept, discussions of the design and expected performance of the EBS device, a description of the EBS experimental program, and a review of the reactor potential of bumpy toroid configurations. Detailed information is presented in the appendices
Yoshii, Yoji
2015-01-01
We define general Lie tori which generalize original Lie tori. We show that a Naoi torus is a general Lie torus. We give examples and prove several properties of general Lie tori. We also review isotopies of Lie tori, and prove that a general Lie torus is, in fact, isotopic to an original Lie torus. Finally, we suggest a very simple way of defining a Lie torus corresponding to a locally extended affine root system R, which we call a Lie R-torus.
Ambipolar potential formation and control in bumpy tori and mirrors
Separate abstracts were prepared for 19 of the included papers. Some of the included papers appeared earlier in ERA. A title listing only is given for three of the papers since only an abstract is given in the conference proceedings
TORIS Data Preparation Guidelines
Guinn, H.; Remson, D.
1999-03-11
The objective of this manual is to present guidelines and procedures for the preparation of new data for the Tertiary Oil Recovery Information System (TORIS) data base. TORIS is an analytical system currently maintained by the Department of Energy's (DOE) Bartlesville Project Office. It uses an extensive field- and reservoir-level data base to evaluate the technical and economic recovery potential of specific crude oil reservoirs.
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
Electrostatic confinement in a bumpy torus
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
Kwakkel, Ferry; Peixoto, Mauricio
2011-01-01
Given a closed Riemannian manifold (M, g), there is a partition \\Sigma_i of its tangent bundle TM called the focal decomposition. The sets \\Sigma_i are closely associated to focusing of geodesics of (M, g), i.e. to the situation where there are exactly i geodesic arcs of the same length joining points p and q in M. In this note, we study the topological structure of the focal decomposition of a closed Riemannian manifold and its relation with the metric structure of the manifold. Our main result is that the flat n-tori are focally rigid, in the sense that if two flat tori are focally equivalent, then the tori are isometric up to rescaling.
Spacetime and orbits of bumpy black holes
Vigeland, Sarah J.; Hughes, Scott A.
2010-01-01
Our Universe contains a great number of extremely compact and massive objects which are generally accepted to be black holes. Precise observations of orbital motion near candidate black holes have the potential to determine if they have the spacetime structure that general relativity demands. As a means of formulating measurements to test the black hole nature of these objects, Collins and Hughes introduced “bumpy black holes”: objects that are almost, but not quite, general relativity’s black holes. The spacetimes of these objects have multipoles that deviate slightly from the black hole solution, reducing to black holes when the deviation is zero. In this paper, we extend this work in two ways. First, we show how to introduce bumps which are smoother and lead to better behaved orbits than those in the original presentation. Second, we show how to make bumpy Kerr black holes—objects which reduce to the Kerr solution when the deviation goes to zero. This greatly extends the astrophysical applicability of bumpy black holes. Using Hamilton-Jacobi techniques, we show how a spacetime’s bumps are imprinted on orbital frequencies, and thus can be determined by measurements which coherently track the orbital phase of a small orbiting body. We find that in the weak field, orbits of bumpy black holes are modified exactly as expected from a Newtonian analysis of a body with a prescribed multipolar structure, reproducing well-known results from the celestial mechanics literature. The impact of bumps on strong-field orbits is many times greater than would be predicted from a Newtonian analysis, suggesting that this framework will allow observations to set robust limits on the extent to which a spacetime’s multipoles deviate from the black hole expectation.
Tori Hobune 2011 & Eesti Hobune 2011 / Krista Sepp
Sepp, Krista
2011-01-01
14. mail korraldas Tori Hobusekasvanduse ratsaspordiklubi XVI Tori hobuse päeva ja esimese ettapi karikasarjas Tori Hobune 2011, kus avastardi takistussõidus tegid ka eesti tõugu hobused, ning 15. mail toimus koolisõidu etapp
Spacetime and orbits of bumpy black holes
Vigeland, Sarah J
2009-01-01
Our universe contains a great number of extremely compact and massive objects which are generally accepted to be black holes. Precise observations of orbital motion near candidate black holes have the potential to determine if they have the spacetime structure that general relativity demands. As a means of formulating measurements to test the black hole nature of these objects, Collins and Hughes introduced "bumpy black holes": objects that are almost, but not quite, general relativity's black holes. The spacetimes of these objects have multipoles that deviate slightly from the black hole solution, reducing to black holes when the deviation is zero. In this paper, we extend this work in two ways. First, we show how to introduce bumps which are smoother and lead to better behaved orbits than those in the original presentation. Second, we show how to make bumpy Kerr black holes -- objects which reduce to the Kerr solution when the deviation goes to zero. This greatly extends the astrophysical applicability of b...
Finite wavelength stability of the bumpy theta pinch
The stability of the bumpy theta pinch is of importance, not only because of its relevance to the Scyllac experiment but also because in any magnetic confinement scheme the use of (discrete) magnetic coils necessarily introduces bumpiness in the applied field. The long wavelength stability has been considered by Weitzner who performed a double perturbation expansion on the linearized equations of ideal MHD: first in epsilon (characterizing the long wave-length or the modes) then in delta (characterizing the bumpiness of the field lines). The stability of the finite wave-length modes by expanding (only) in the small bumpiness parameter delta is examined. Currents flow only in the ignorable theta direction. (U.K.)
Magnetics calculations for an ELMO Bumpy Square
Calculations have been carried out to determine the vacuum magnetic parameters, forces, and the use of trim coils in an ELMO Bumpy Square. A configuration having five mirror coils per side and an eight-coil high-field toroidal solenoid corner assembly was studied. Favorable magnetic parameters are achieved in the device. An on-axis mirror ratio of 1.9, a global mirror ratio of 3.6, and excellent centering of plasma pressure contours are achieved. Particle losses are also minimal (<5%). The magnetic forces acting between coils are comparable with those encountered in the EBT-I/S magnet configuration. Circular trim coils were found to be suitable for restoring hot electron ring locations that are displaced when the coil currents are varied for performing magnetic studies or for assessing the effects on the EBS of the global mirror ratio
Thomson scattering on ELMO Bumpy Torus
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
ELMO Bumpy Torus Reactor (EBTR) reference design
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
Oral Tori in Chronic Peritoneal Dialysis Patients
Hsu, Chia-Lin; Hsu, Ching-Wei; Chang, Pei-Ching; Huang, Wen-Hung; Weng, Cheng-Hao; Yang, Huang-Yu; Liu, Shou-Hsuan; Chen, Kuan-Hsing; Weng, Shu-Man; Chang, Chih-Chun; Wang, I-Kuan
2016-01-01
Background The pathogenesis of oral tori has long been debated and is thought to be the product of both genetic and environmental factors, including occlusal forces. Another proposed mechanism for oral tori is the combination of biomechanical forces, particularly in the oral cavity, combined with cortical bone loss and trabecular expansion, as one might see in the early stages of primary hyperparathyroidism. This study investigated the epidemiology of torus palatinus (TP) and torus mandibularis (TM) in peritoneal dialysis patients, and analyzed the influences of hyperparathyroidism on the formation of oral tori. Method In total, 134 peritoneal dialysis patients were recruited between July 1 and December 31, 2015 for dental examinations for this study. Patients were categorized into two subgroups based on the presence or absence of oral tori. Demographic, hematological, biochemical, and dialysis-related data were obtained for analysis. Results The prevalence of oral tori in our sample group was high at 42.5% (57 of 134), and most patients with oral tori were female (61.4%). The most common location of tori was TP (80.7%), followed by TP and TM (14.0%), then TM (5.3%). All 54 TP cases were at the midline, and most were <2 cm (59.3%), flat (53.7%), and located in the premolar region (40.7%). Of the 11 TM cases, all were bilateral and symmetric, mostly <2 cm (81.9%), lobular (45.4%), and located at premolar region (63.6%). Interestingly, patients with oral tori had slightly lower serum levels of intact parathyroid hormones than those without oral tori, but the difference was not statistically significant (317.3±292.0 versus 430.1±492.6 pg/mL, P = 0.126). In addition, patients with oral tori did not differ from patients without tori in inflammatory variables such as serum high sensitivity C-reactive protein levels (6.6±8.2 versus 10.3±20.2 mg/L, P = 0.147) or nutritional variables such as serum albumin levels (3.79±0.38 versus 3.77±0.45 g/dL, P = 0
Oral Tori in Chronic Peritoneal Dialysis Patients.
Chia-Lin Hsu
Full Text Available The pathogenesis of oral tori has long been debated and is thought to be the product of both genetic and environmental factors, including occlusal forces. Another proposed mechanism for oral tori is the combination of biomechanical forces, particularly in the oral cavity, combined with cortical bone loss and trabecular expansion, as one might see in the early stages of primary hyperparathyroidism. This study investigated the epidemiology of torus palatinus (TP and torus mandibularis (TM in peritoneal dialysis patients, and analyzed the influences of hyperparathyroidism on the formation of oral tori.In total, 134 peritoneal dialysis patients were recruited between July 1 and December 31, 2015 for dental examinations for this study. Patients were categorized into two subgroups based on the presence or absence of oral tori. Demographic, hematological, biochemical, and dialysis-related data were obtained for analysis.The prevalence of oral tori in our sample group was high at 42.5% (57 of 134, and most patients with oral tori were female (61.4%. The most common location of tori was TP (80.7%, followed by TP and TM (14.0%, then TM (5.3%. All 54 TP cases were at the midline, and most were <2 cm (59.3%, flat (53.7%, and located in the premolar region (40.7%. Of the 11 TM cases, all were bilateral and symmetric, mostly <2 cm (81.9%, lobular (45.4%, and located at premolar region (63.6%. Interestingly, patients with oral tori had slightly lower serum levels of intact parathyroid hormones than those without oral tori, but the difference was not statistically significant (317.3±292.0 versus 430.1±492.6 pg/mL, P = 0.126. In addition, patients with oral tori did not differ from patients without tori in inflammatory variables such as serum high sensitivity C-reactive protein levels (6.6±8.2 versus 10.3±20.2 mg/L, P = 0.147 or nutritional variables such as serum albumin levels (3.79±0.38 versus 3.77±0.45 g/dL, P = 0.790. Furthermore, there were no
Quasi-periodic oscillations of perturbed tori
Parthasarathy, Varadarajan; Manousakis, Antonios; Kluźniak, Włodzimierz
2016-05-01
We performed axisymmetric hydrodynamical simulations of oscillating tori orbiting a non-rotating black hole. The tori in equilibrium were constructed with a constant distribution of angular momentum in a pseudo-Newtonian potential (Kluźniak-Lee). Motions of the torus were triggered by adding subsonic velocity fields: radial, vertical and diagonal to the tori in equilibrium. As the perturbed tori evolved in time, we measured L2 norm of density and obtained the power spectrum of L2 norm which manifested eigenfrequencies of tori modes. The most prominent modes of oscillation excited in the torus by a quasi-random perturbation are the breathing mode and the radial and vertical epicyclic modes. The radial and the plus modes, as well as the vertical and the breathing modes will have frequencies in an approximate 3:2 ratio if the torus is several Schwarzschild radii away from the innermost stable circular orbit. Results of our simulations may be of interest in the context of high-frequency quasi-periodic oscillations observed in stellar-mass black hole binaries, as well as in supermassive black holes.
Summary of ELMO Bumpy Torus experiments from 1982 to 1984
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
Stokes flow through a tube with bumpy wall
Wang, C. Y.
2006-07-01
The Stokes flow through a tube with a bumpy wall is solved through a perturbation in the small amplitude of the three-dimensional bumps. The solution can be expressed in terms of modified Bessel functions. For given area or volume of a bump, there exists an optimum circumferential wave number and an optimum aspect ratio for which the flow rate is maximized.
(Tory) anarchy in the UK: The very peculiar practice of tory anarchism
Wilkin, P.
2009-01-01
The idea of ‘Tory Anarchism’ is reasonably well known but largely unanalysed in either popular or academic literature. Tory Anarchism refers to a group of apparently disparate figures in English popular and political culture whose work has, in part, satirised key British institutions and social relations. At the same time they also provide interesting insights into questions of British, though predominantly English, identity, by focusing upon issues of class, empire and nation. This article ...
Liouville quantum gravity on complex tori
David, François [Institut de Physique Théorique, CNRS, URA 2306, CEA, IPhT, Gif-sur-Yvette (France); Rhodes, Rémi [Université Paris-Est Marne la Vallée, LAMA, Champs sur Marne (France); Vargas, Vincent [ENS Paris, DMA, 45 rue d’Ulm, 75005 Paris (France)
2016-02-15
In this paper, we construct Liouville Quantum Field Theory (LQFT) on the toroidal topology in the spirit of the 1981 seminal work by Polyakov [Phys. Lett. B 103, 207 (1981)]. Our approach follows the construction carried out by the authors together with Kupiainen in the case of the Riemann sphere [“Liouville quantum gravity on the Riemann sphere,” e-print arXiv:1410.7318]. The difference is here that the moduli space for complex tori is non-trivial. Modular properties of LQFT are thus investigated. This allows us to integrate the LQFT on complex tori over the moduli space, to compute the law of the random Liouville modulus, therefore recovering (and extending) formulae obtained by physicists, and make conjectures about the relationship with random planar maps of genus one, eventually weighted by a conformal field theory and conformally embedded onto the torus.
Liouville quantum gravity on complex tori
David, François; Rhodes, Rémi; Vargas, Vincent
2016-02-01
In this paper, we construct Liouville Quantum Field Theory (LQFT) on the toroidal topology in the spirit of the 1981 seminal work by Polyakov [Phys. Lett. B 103, 207 (1981)]. Our approach follows the construction carried out by the authors together with Kupiainen in the case of the Riemann sphere ["Liouville quantum gravity on the Riemann sphere," e-print arXiv:1410.7318]. The difference is here that the moduli space for complex tori is non-trivial. Modular properties of LQFT are thus investigated. This allows us to integrate the LQFT on complex tori over the moduli space, to compute the law of the random Liouville modulus, therefore recovering (and extending) formulae obtained by physicists, and make conjectures about the relationship with random planar maps of genus one, eventually weighted by a conformal field theory and conformally embedded onto the torus.
Liouville quantum gravity on complex tori
In this paper, we construct Liouville Quantum Field Theory (LQFT) on the toroidal topology in the spirit of the 1981 seminal work by Polyakov [Phys. Lett. B 103, 207 (1981)]. Our approach follows the construction carried out by the authors together with Kupiainen in the case of the Riemann sphere [“Liouville quantum gravity on the Riemann sphere,” e-print arXiv:1410.7318]. The difference is here that the moduli space for complex tori is non-trivial. Modular properties of LQFT are thus investigated. This allows us to integrate the LQFT on complex tori over the moduli space, to compute the law of the random Liouville modulus, therefore recovering (and extending) formulae obtained by physicists, and make conjectures about the relationship with random planar maps of genus one, eventually weighted by a conformal field theory and conformally embedded onto the torus
Line emission from optically thick relativistic accretion tori
Fuerst, Steven V.; Wu, Kinwah
2007-01-01
We calculate line emission from relativistic accretion tori around Kerr black holes and investigate how the line profiles depend on the viewing inclination, spin of the central black hole, parameters describing the shape of the tori, and spatial distribution of line emissivity on the torus surface. We also compare the lines with those from thin accretion disks. Our calculations show that lines from tori and lines from thin disks share several common features. In particular, at low and moderat...
ELMO Bumpy Torus fusion-reactor design study
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
Singular limit cycle bifurcations to closed orbits and invariant tori
This paper investigates singular limit cycle bifurcations for a singularly perturbed system. Based on a series of transformations (the modified curvilinear coordinate, blow-up, and near-identity transformation) and bifurcation theory of periodic orbits and invariant tori, the bifurcations of closed orbits and invariant tori near singular limit cycles are discussed
Singular limit cycle bifurcations to closed orbits and invariant tori
Ye Zhiyong [Department of Mathematics, Shanghai Jiaotong University, Shanghai 200240 (China); Department of Mathematics, Chongqing Institute of Technology, Chongqing 400050 (China); E-mail: yezhiyong@sjtu.edu.cn; Han Maoan [Department of Mathematics, Shanghai Jiaotong University, Shanghai 200240 (China); E-mail: mahan@sjtu.edu.cn
2006-02-01
This paper investigates singular limit cycle bifurcations for a singularly perturbed system. Based on a series of transformations (the modified curvilinear coordinate, blow-up, and near-identity transformation) and bifurcation theory of periodic orbits and invariant tori, the bifurcations of closed orbits and invariant tori near singular limit cycles are discussed.
Curved noncommutative tori as Leibniz quantum compact metric spaces
Latrémolière, Frédéric, E-mail: frederic@math.du.edu [Department of Mathematics, University of Denver, Denver, Colorado 80208 (United States)
2015-12-15
We prove that curved noncommutative tori are Leibniz quantum compact metric spaces and that they form a continuous family over the group of invertible matrices with entries in the image of the quantum tori for the conjugation by modular conjugation operator in the regular representation, when this group is endowed with a natural length function.
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
Charged tori in spherical gravitational and dipolar magnetic fields
Slany, P; Stuchlik, Z; Karas, V
2013-01-01
A Newtonian model of non-conductive, charged, perfect fluid tori orbiting in combined spherical gravitational and dipolar magnetic fields is presented and stationary, axisymmetric toroidal structures are analyzed. Matter in such tori exhibits a purely circulatory motion and the resulting convection carries charges into permanent rotation around the symmetry axis. As a main result, we demonstrate the possible existence of off-equatorial charged tori and equatorial tori with cusps enabling outflows of matter from the torus also in the Newtonian regime. These phenomena represent qualitatively a new consequence of the interplay between gravity and electromagnetism. From an astrophysical point of view, our investigation can provide insight into processes that determine the vertical structure of dusty tori surrounding accretion disks.
CHARGED TORI IN SPHERICAL GRAVITATIONAL AND DIPOLAR MAGNETIC FIELDS
Slany, P.; Kovar, J.; Stuchlik, Z. [Institute of Physics, Faculty of Philosophy and Science, Silesian University in Opava Bezrucovo nam. 13, CZ-746 01 Opava (Czech Republic); Karas, V., E-mail: petr.slany@fpf.slu.cz [Astronomical Institute, Academy of Sciences, Bocni II, Prague CZ-141 31 (Czech Republic)
2013-03-01
A Newtonian model of non-conductive, charged, perfect fluid tori orbiting in combined spherical gravitational and dipolar magnetic fields is presented and stationary, axisymmetric toroidal structures are analyzed. Matter in such tori exhibits a purely circulatory motion and the resulting convection carries charges into permanent rotation around the symmetry axis. As a main result, we demonstrate the possible existence of off-equatorial charged tori and equatorial tori with cusps that also enable outflows of matter from the torus in the Newtonian regime. These phenomena qualitatively represent a new consequence of the interplay between gravity and electromagnetism. From an astrophysical point of view, our investigation can provide insight into processes that determine the vertical structure of dusty tori surrounding accretion disks.
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.
ELMO Bumpy Torus Reactor and power plant: conceptual design study
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
Transient waveform acquisition system for the ELMO Bumpy Torus
The transient waveform system described in this report is designed to acquire analog waveforms from the ELMO Bumpy Torus (EBT) diagnostic experiments. Pressure, density, synchrotron radiation, etc., are acquired and digitized with a Kinetic Systems TR812 transient recorder and associated modules located in a CAMAC crate. The system can simultaneously acquire, display, and transmit sets of data consisting of identification parameters and up to 1024 data points for 1 to 64 input signals (frequency range = 0.01 pulse/s to 100 kHz) of data every one or more minutes; thus, it can run continuously without operator intervention. The data are taken on a VAX 11/780 and transmitted to a data base on a DECSystem-10. To aid the programmer in making future modifications to the system, detailed documentation using the Yourdon structural methods has been given
Theoretical studies of Elmo Bumpy Torus. Annual report
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
Three-dimensional tori and Arnold tongues
Sekikawa, Munehisa; Inaba, Naohiko; Kamiyama, Kyohei; Aihara, Kazuyuki
2014-03-01
This study analyzes an Arnold resonance web, which includes complicated quasi-periodic bifurcations, by conducting a Lyapunov analysis for a coupled delayed logistic map. The map can exhibit a two-dimensional invariant torus (IT), which corresponds to a three-dimensional torus in vector fields. Numerous one-dimensional invariant closed curves (ICCs), which correspond to two-dimensional tori in vector fields, exist in a very complicated but reasonable manner inside an IT-generating region. Periodic solutions emerge at the intersections of two different thin ICC-generating regions, which we call ICC-Arnold tongues, because all three independent-frequency components of the IT become rational at the intersections. Additionally, we observe a significant bifurcation structure where conventional Arnold tongues transit to ICC-Arnold tongues through a Neimark-Sacker bifurcation in the neighborhood of a quasi-periodic Hopf bifurcation (or a quasi-periodic Neimark-Sacker bifurcation) boundary.
Three-dimensional tori and Arnold tongues
Sekikawa, Munehisa, E-mail: sekikawa@cc.utsunomiya-u.ac.jp [Department of Mechanical and Intelligent Engineering, Utsunomiya University, Utsunomiya-shi 321-8585 (Japan); Inaba, Naohiko [Organization for the Strategic Coordination of Research and Intellectual Property, Meiji University, Kawasaki-shi 214-8571 (Japan); Kamiyama, Kyohei [Department of Electronics and Bioinformatics, Meiji University, Kawasaki-shi 214-8571 (Japan); Aihara, Kazuyuki [Institute of Industrial Science, the University of Tokyo, Meguro-ku 153-8505 (Japan)
2014-03-15
This study analyzes an Arnold resonance web, which includes complicated quasi-periodic bifurcations, by conducting a Lyapunov analysis for a coupled delayed logistic map. The map can exhibit a two-dimensional invariant torus (IT), which corresponds to a three-dimensional torus in vector fields. Numerous one-dimensional invariant closed curves (ICCs), which correspond to two-dimensional tori in vector fields, exist in a very complicated but reasonable manner inside an IT-generating region. Periodic solutions emerge at the intersections of two different thin ICC-generating regions, which we call ICC-Arnold tongues, because all three independent-frequency components of the IT become rational at the intersections. Additionally, we observe a significant bifurcation structure where conventional Arnold tongues transit to ICC-Arnold tongues through a Neimark-Sacker bifurcation in the neighborhood of a quasi-periodic Hopf bifurcation (or a quasi-periodic Neimark-Sacker bifurcation) boundary.
Modular Curvature for Noncommutative Two-Tori
Connes, Alain
2011-01-01
Starting from the description of the conformal geometry of noncommutative 2-tori in the framework of modular spectral triples, we explicitly compute the local curvature functionals determined by the value at zero of the zeta functions affiliated with these spectral triples. We give a closed formula for the Ray-Singer analytic torsion in terms of the Dirichlet quadratic form and the generating function for Bernoulli numbers applied to the modular operator. The gradient of the Ray-Singer analytic torsion is then expressed in terms of these functionals, and yields the analogue of scalar curvature. Computing this gradient in two ways elucidates the meaning of the complicated two variable functions occurring in the formula for the scalar curvature. Moreover, the corresponding evolution equation for the metric produces the appropriate analogue of Ricci curvature. We prove the analogue of the classical result which asserts that in every conformal class the maximum value of the determinant of the Laplacian on metrics...
Toris väärtustub ameeriklaste panus / Silvia Paluoja
Paluoja, Silvia, 1956-
2010-01-01
President Toomas Hendrik Ilves ja Ameerika Ühendriikide suursaadik Michael C. Polt avasid 22. juunil 2010. a. Tori alevikus Eesti Sõjameeste Mälestuskirikus mälestusplaadi Ameerika Ühendriikide kodanikest Vabadusristi kavaleridele
On Lower Dimensional Invariant Tori in Cd Reversible Systems
Jing ZHANG
2008-01-01
In this paper,a result on the persistence of lowner dimensional invariant tori in Cd reversible systems is obtained under some conditions.The theorem is proved for any d which is larger than some consts.
Rational points of bounded height on compactifications of anisotropic tori
Batyrev, V V; Batyrev, Victor V; Tschinkel, Yuri
1994-01-01
We investigate the analytic properties of the zeta-function associated with heights on equivariant compactifications of anisotropic tori over number fields. This allows to verify conjectures about the distribution of rational points of bounded height.
Tori hobuse mitu palet ja ametit / Vivika Veski
Veski, Vivika
2008-01-01
Tori hobusekasvandus pürib turismiäri ja toetuste abiga üle-eestilise haardega tõuaretuskeskuseks. Küsimusele, mida arvate plaanist luua Torisse hobuste aretamise keskus, vastavad Peep Puna ja Raigo Kollom
Surface flute modes in the bumpy magnetic field
Surface electromagnetic waves are often determined as the most possible cause of undesirable heating of edge plasma that leads, in turn, to strengthening of plasma - wall interaction in stellarators and increased plasma contamination. The propagation of surface flute modes near the interface of plasma column separated by a vacuum layer from the ring cylindrical ideally conductive metallic chamber is studied. The external steady bumpy magnetic field B-vector0 = B0ze-vectorz + B0re-vectorr was considered, B0z=B00[1+εm(r)cos(kmz)], here εm'≡dεm/dr, km=2π/L, L is the period of nonuniformity. non-uniformity of B-vector0 is planned to be dominant in the confining magnetic field of the modular stellarator Helias, εm ∼ 0.13. In the bumpy magnetic field the electromagnetic disturbance propagates in the form of the wave envelope, in which one alongside with the fundamental harmonic, proportional to exp[i(mθ±-ωt)], infinite set of satellite spatial harmonics, proportional to exp[i(mθ ± jkmz - ωt)], j=1,2,3..., is present. It is shown, that in the first approximation in the respect to εm, amplitudes of the fundamental harmonics of the E-wave with the field components Er, Eθ, Bz do not vary, small satellite harmonics of these fields arise, proportional to exp[i(mθ ± kmz - ωt)]. At the same time due to weak coupling of - and - modes, caused by B-vector0 nonuniformity and nonzero axial wave number of satellite harmonics, small satellite harmonics of H-wave with the field components Ez, Br, Bθ also arise. The amplitudes of satellite harmonics of E-wave are shown to be symmetric: Er(+)=Er(-), Eθ(+)=Eθ(-), Bz(+)=Bz(-), and the amplitudes of H-wave are antisymmetric: Br(+)=-Br(-), Bθ(+)=- Bθ(-), Ez(+)=-Ez(-). In the second approximation in the respect to εm corrections to the amplitudes of the fundamental harmonic of E-wave arise. The correction to the eigen frequency of the wave, caused by the nonuniformity of B-vector0, appears to be the small value of the
Normal linear stability of quasi-periodic tori
Broer, H. W.; Hoo, J.; Naudot, V.
We consider families of dynamical systems having invariant tori that carry quasi-periodic motions. Our interest is the persistence of such tori under small, nearly-integrable perturbations. This persistence problem is studied in the dissipative, the Hamiltonian and the reversible setting, as part of a more general KAM theory for classes of structure preserving dynamical systems. This concerns the parametrized KAM theory as initiated by Moser [J.K. Moser, On the theory of quasiperiodic motions, SIAM Rev. 8 (2) (1966)145-172; J.K. Moser, Convergent series expansions for quasi-periodic motions, Math. Ann. 169 (1967) 136-176] and further developed in [G.B. Huitema, Unfoldings of quasi-periodic tori, PhD thesis, University of Groningen, 1988; H.W. Broer, G.B. Huitema, F. Takens, Unfoldings of quasi-periodic tori, Mem. Amer. Math. Soc. 83 (421) (1990) 1-82; H.W. Broer, G.B. Huitema, Unfoldings of quasi-periodic tori in reversible systems, J. Dynam. Differential Equations 7 (1) (1995) 191-212]. The corresponding nondegeneracy condition involves certain (trans-)versality conditions on the normal linear, leading, part at the invariant tori. We show that as a consequence, a Cantor family of Diophantine tori with positive Hausdorff measure is persistent under nearly-integrable perturbations. This result extends the above references since presently the case of multiple Floquet exponents is included. Our leading example is the normal 1 :-1 resonance, which occurs a lot in applications, both Hamiltonian and reversible. As an illustration of this we briefly describe the Lagrange top coupled to an oscillator.
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.
Radial transport in the ELMO Bumpy Torus in collisionless regimes
One important area of disagreement between radial transport theory and the ELMO Bumpy Torus experiment (EBT) has been the degree of collisionality of the toroidal plasma electrons. Experiment shows relatively warm electrons (kT/sub e/ approx. 300 to 600 eV) and collisionless scaling, that is, energy confinement increasing with temperature. But results of early one-dimensional (1-D), neoclassical transport models with radially inward pointing electric fields are limited to relatively cool electrons (kT/sub e/ approx. 100 to 200 eV) and collisional scaling. In this paper these early results are extended to include lowest order effects of ion diffusion in regions where poloidal drift frequencies are small. Effects of direct, or nondiffusive, losses in such regions are neglected. Results show that solutions in the collisionless regime do exist. Furthermore, when effects of finite electron ring beta on magnetic fields near the plasma edge are included, these solutions occur at power levels consistent with experiment
Invariant tori for a class of nonlinear evolution equations
The paper looks at quite a wide class of nonlinear evolution equations in a Banach space, including the typical boundary value problems for the main wave equations in mathematical physics (the telegraph equation, the equation of a vibrating beam, various equations from the elastic stability and so on). For this class of equations a unified approach to the bifurcation of invariant tori of arbitrary finite dimension is put forward. Namely, the problem of the birth of such tori from the zero equilibrium is investigated under the assumption that in the stability problem for this equilibrium the situation arises close to an infinite-dimensional degeneracy. Bibliography: 28 titles
Mind the Resonances: Final stages of accretion into bumpy black holes
In this article we discuss a possible way of testing the Kerr black hole hypothesis by taking advantage of phenomena correlated with chaotic motion in the final stages of an accretion disk around a bumpy black hole. We anticipate that these phenomena should have an imprint in the electromagnetic spectrum coming from the accretion disk
Roles of bumpy field on collisionless particle confinement in helical axis heliotrons
The roles of 'bumpy' field on collisionless particle confinement in helical axis heliotrons are investigated with model magnetic field and particle orbit calculations in Boozer co-ordinates. The mod Bmin contours can be shifted in the major radius direction with control of the bumpy field, where Bmin is the minimum value of vertical bar B vertical bar in the toroidal direction within one field period. The area of closed mod Bmin contours is a useful measure with which to evaluate global collisionless particle confinement as long as the mod Bmin contours connect toroidally. The negative value of the ratio between the bumpy component and the helicity component contributes to obtaining the largest area of closed mod Bmin contours for a finite ratio between the toroidicity component and the helicity component. The radially increasing bumpy field contributes to the realization of a toroidally localized mod Bmin structure. It also produces a region with a large derivative of vertical bar B vertical bar with respect to the toroidal magnetic flux, which is well aligned to the toroidally localized mod Bmin structure. This enhances the large poloidal drift of the guiding centre orbits, while the radial drift is unaffected, effectively improving the particle confinement. (author)
In June 2006 a study was finalized on the Liberalisation of the Dutch Energy Market. The European Commission decided to liberalise the European energy industry, the Netherlands taking the lead. The Dutch electricity and natural gas industries fell prey to a bumpy road of liberalization; initial expectations have proven to be overly optimistic
Küsimuste tulv automaksu teel / Villem Tori
Tori, Villem
2008-01-01
Eesti Autoettevõtete Liidu direktor Villem Tori imestab sotsiaaldemokraatide automaksu idee üle, sest kordagi pole öeldud, mida sellest maksust laekuva rahaga teha soovitakse. Vt. samas: Võimalik automaks. Kommenteerivad võimlemisklubi Janika juht Janika Mölder ja suusatreener Mati Alaver
Erakordne jumalateenistus Eesti Sõjameeste Mälestuskirikus Toris / Kuno Raude
Raude, Kuno
2010-01-01
22. juunil 2010. a. Toris Eesti Sõjameeste Mälestuskirikus toimunud jumalateenistusest, millest võttis osa ka president Toomas Hendrik Ilves. Eesti riigipea avas koos USA suursaadikuga Eestis Michael C. Polt'iga Ameerika Ühendriikide kodanikest Vabadusristi kavaleridele pühendatud mälestusplaadi
Line Emission from Optically Thick RelativisticAccretion Tori
Fuerst, Steven V.; /KIPAC, Menlo Park /Mullard Space Sci. Lab.; Wu, Kinwah; /Mullard Space Sci. Lab.
2007-09-14
We calculate line emission from relativistic accretion tori around Kerr black holes and investigate how the line profiles depend on the viewing inclination, spin of the central black hole, parameters describing the shape of the tori, and spatial distribution of line emissivity on the torus surface. We also compare the lines with those from thin accretion disks. Our calculations show that lines from tori and lines from thin disks share several common features. In particular, at low and moderate viewing inclination angles they both have asymmetric double-peaked profiles with a tall, sharp blue peak and a shorter red peak which has an extensive red wing. At high viewing inclination angles they both have very broad, asymmetric lines which can be roughly considered as single-peaked. Torus and disk lines may show very different red and blue line wings, but the differences are due to the models for relativistic tori and disks having differing inner boundary radii. Self-eclipse and lensing play some role in shaping the torus lines, but they are effective only at high inclination angles. If inner and outer radii of an accretion torus are the same as those of an accretion disk, their line profiles show substantial differences only when inclination angles are close to 90{sup o}, and those differences are manifested mostly at the central regions of the lines instead of the wings.
Line emission from optically thick relativistic accretion tori
Fuerst, Steven V
2007-01-01
We calculate line emission from relativistic accretion tori around Kerr black holes and investigate how the line profiles depend on the viewing inclination, spin of the central black hole, parameters describing the shape of the tori, and spatial distribution of line emissivity on the torus surface. We also compare the lines with those from thin accretion disks. Our calculations show that lines from tori and lines from thin disks share several common features. In particular, at low and moderate viewing inclination angles they both have asymmetric double-peaked profiles with a tall, sharp blue peak and a shorter red peak which has an extensive red wing. At high viewing inclination angles they both have very broad, asymmetric lines which can be roughly considered single-peaked. Torus and disk lines may show very different red and blue line wings, but the differences are due to the models for relativistic tori and disks having differing inner boundary radii. Self-eclipse and lensing play some role in shaping the ...
Scale invariant Strichartz estimates on tori and applications
Killip, Rowan; Visan, Monica
2014-01-01
We prove scale-invariant Strichartz inequalities for the Schrodinger equation on rectangular tori (rational or irrational) in all dimensions. We use these estimates to give a unified and simpler treatment of local well-posedness of the energy-critical nonlinear Schrodinger equation in dimensions three and four.
Once-punctured tori and knots in lens spaces
Baker, Kenneth L.
2006-01-01
We determine the non-null homologous knots in lens spaces whose exteriors contain properly embedded once-punctured tori. All such knots arise as surgeries on the Whitehead link and are grid number 1 in their lens spaces. As a corollary, we classify once-punctured torus bundles that admit a lens space filling.
Perfect fluid tori orbiting Kehagias-Sfetsos naked singularities
Stuchlík, Z.; Pugliese, D.; Schee, J.; Kučáková, H.
2015-09-01
We construct perfect fluid tori in the field of the Kehagias-Sfetsos (K-S) naked singularities. These are spherically symmetric vacuum solutions of the modified Hořava quantum gravity, characterized by a dimensionless parameter ω M^2, combining the gravitational mass parameter M of the spacetime with the Hořava parameter ω reflecting the role of the quantum corrections. In dependence on the value of ω M^2, the K-S naked singularities demonstrate a variety of qualitatively different behavior of their circular geodesics that is fully reflected in the properties of the toroidal structures, demonstrating clear distinction to the properties of the torii in the Schwarzschild spacetimes. In all of the K-S naked singularity spacetimes the tori are located above an "antigravity" sphere where matter can stay in a stable equilibrium position, which is relevant for the stability of the orbiting fluid toroidal accretion structures. The signature of the K-S naked singularity is given by the properties of marginally stable tori orbiting with the uniform distribution of the specific angular momentum of the fluid, l= const. In the K-S naked singularity spacetimes with ω M^2 > 0.2811, doubled tori with the same l= const can exist; mass transfer between the outer torus and the inner one is possible under appropriate conditions, while only outflow to the outer space is allowed in complementary conditions. In the K-S spacetimes with ω M^2 < 0.2811, accretion from cusped perfect fluid tori is not possible due to the non-existence of unstable circular geodesics.
Perfect fluid tori orbiting Kehagias-Sfetsos naked singularities
Stuchlik, Z.; Pugliese, D.; Schee, J.; Kucakova, H. [Silesian University in Opava, Faculty of Philosophy and Science, Institute of Physics and Research Centre of Theoretical Physics and Astrophysics, Opava (Czech Republic)
2015-09-15
We construct perfect fluid tori in the field of the Kehagias-Sfetsos (K-S) naked singularities. These are spherically symmetric vacuum solutions of the modified Horava quantum gravity, characterized by a dimensionless parameter ωM{sup 2}, combining the gravitational mass parameter M of the spacetime with the Horava parameter ω, reflecting the role of the quantum corrections. In dependence on the value of ωM{sup 2}, the K-S naked singularities demonstrate a variety of qualitatively different behavior of their circular geodesics that is fully reflected in the properties of the toroidal structures, demonstrating clear distinction to the properties of the torii in the Schwarzschild spacetimes. In all of the K-S naked singularity spacetimes the tori are located above an @gantigravity@h sphere where matter can stay in a stable equilibrium position, which is relevant for the stability of the orbiting fluid toroidal accretion structures. The signature of the K-S naked singularity is given by the properties of marginally stable tori orbiting with the uniform distribution of the specific angular momentum of the fluid, l = const. In the K-S naked singularity spacetimes with ωM{sup 2} > 0.2811, doubled tori with the same l = const can exist; mass transfer between the outer torus and the inner one is possible under appropriate conditions, while only outflow to the outer space is allowed in complementary conditions. In the K-S spacetimes with ωM{sup 2} < 0.2811, accretion from cusped perfect fluid tori is not possible due to the non-existence of unstable circular geodesics. (orig.)
Perfect fluid tori orbiting Kehagias-Sfetsos naked singularities
We construct perfect fluid tori in the field of the Kehagias-Sfetsos (K-S) naked singularities. These are spherically symmetric vacuum solutions of the modified Horava quantum gravity, characterized by a dimensionless parameter ωM2, combining the gravitational mass parameter M of the spacetime with the Horava parameter ω, reflecting the role of the quantum corrections. In dependence on the value of ωM2, the K-S naked singularities demonstrate a variety of qualitatively different behavior of their circular geodesics that is fully reflected in the properties of the toroidal structures, demonstrating clear distinction to the properties of the torii in the Schwarzschild spacetimes. In all of the K-S naked singularity spacetimes the tori are located above an @gantigravity@h sphere where matter can stay in a stable equilibrium position, which is relevant for the stability of the orbiting fluid toroidal accretion structures. The signature of the K-S naked singularity is given by the properties of marginally stable tori orbiting with the uniform distribution of the specific angular momentum of the fluid, l = const. In the K-S naked singularity spacetimes with ωM2 > 0.2811, doubled tori with the same l = const can exist; mass transfer between the outer torus and the inner one is possible under appropriate conditions, while only outflow to the outer space is allowed in complementary conditions. In the K-S spacetimes with ωM2 < 0.2811, accretion from cusped perfect fluid tori is not possible due to the non-existence of unstable circular geodesics. (orig.)
Oscillations of radiation pressure supported tori near black holes
Mazur, Grzegorz P; Sądowski, Aleksander; Mishra, Bhupendra; Kluźniak, Włodek
2015-01-01
We study the dynamics of radiation pressure supported tori around Schwarzschild black holes, focusing on their oscillatory response to an external perturbation. Using KORAL, a general relativistic radiation hydrodynamics code capable of modeling all radiative regimes from the optically thick to the optically thin, we monitor a sample of models at different initial temperatures and opacities, evolving them in two spatial dimensions for $\\sim 165$ orbital periods. The dynamics of models with high opacity is very similar to that of purely hydrodynamics models, and it is characterized by regular oscillations which are visible also in the light curves. As the opacity is decreased, the tori quickly and violently migrate towards the gas-pressure dominated regime, collapsing towards the equatorial plane. When the spectra of the $L_2$ norm of the mass density are considered, high frequency inertial-acoustic modes of oscillations are detected (with the fundamental mode at a frequency $68 M_{\\rm BH}^{-1}\\,\\rm Hz$), in c...
Mechanisms of Stochastic Diffusion of Energetic Ions in Spherical Tori
Stochastic diffusion of the energetic ions in spherical tori is considered. The following issues are addressed: (I) Goldston-White-Boozer diffusion in a rippled field; (ii) cyclotron-resonance-induced diffusion caused by the ripple; (iii) effects of non-conservation of the magnetic moment in an axisymmetric field. It is found that the stochastic diffusion in spherical tori with a weak magnetic field has a number of peculiarities in comparison with conventional tokamaks; in particular, it is characterized by an increased role of mechanisms associated with non-conservation of the particle magnetic moment. It is concluded that in current experiments on National Spherical Torus eXperiment (NSTX) the stochastic diffusion does not have a considerable influence on the confinement of energetic ions
Perfect fluid tori orbiting Kehagias-Sfetsos naked singularities
Stuchlík, Zdeněk; Schee, Jan; Kučáková, Hana
2014-01-01
We construct perfect fluid tori in the field of the Kehagias-Sfetsos (K-S) naked singularity representing spherically symmetric vacuum solution of the modified Ho\\v{r}ava quantum gravity that is characterized by a dimensionless parameter $\\omega M^2$, combining the gravitational mass parameter $M$ of the spacetime with the Ho\\v{r}ava parameter $\\omega$ reflecting the role of the quantum corrections. In dependence on the value of $\\omega M^2$, the K-S naked singularities demonstrate a variety of qualitatively different behavior of their circular geodesics that is fully reflected in the properties of the toroidal structures. In all of the K-S naked singularity spacetimes the tori are located above an "antigravity" sphere where matter can stay in stable equilibrium position, that is relevant for the stability of the orbiting fluid toroidal accretion structures.
Classification of knotted tori in 2-metastable dimension
Cencelj, Matija
2012-11-30
This paper is devoted to the classical Knotting Problem: for a given manifold N and number m describe the set of isotopy classes of embeddings N → Sm. We study the specific case of knotted tori, that is, the embeddings Sp × Sq → Sm. The classification of knotted tori up to isotopy in the metastable dimension range m > p + 3 2 q + 2, p 6 q, was given by Haefliger, Zeeman and A. Skopenkov. We consider the dimensions below the metastable range and give an explicit criterion for the finiteness of this set of isotopy classes in the 2-metastable dimension: Theorem. Assume that p+ 4 3 q +2 < mp+ 3 2 q +2 and m > 2p+q +2. Then the set of isotopy classes of smooth embeddings Sp × Sq → Sm is infinite if and only if either q + 1 or p + q + 1 is divisible by 4. © 2012 RAS(DoM) and LMS.
Circular geodesics and thick tori around rotating boson stars
Meliani, Z; Grandclément, P; Gourgoulhon, E; Monceau-Baroux, R; Straub, O
2015-01-01
Accretion disks play an important role in the evolution of their relativistic inner compact objects. The emergence of a new generation of interferometers will allow to resolve these accretion disks and provide more information about the properties of the central gravitating object. Due to this instrumental leap forward it is crucial to investigate the accretion disk physics near various types of inner compact objects now to deduce later constraints on the central objects from observations. A possible candidate for the inner object is the boson star. Here, we will try to analyze the differences between accretion structures surrounding boson stars and black holes. We aim at analysing the physics of circular geodesics around boson stars and study simple thick accretion tori (so-called Polish doughnuts) in the vicinity of these stars. We realize a detailed study of the properties of circular geodesics around boson stars. We then perform a parameter study of thick tori with constant angular momentum surrounding bo...
Existence of Invariant Tori for Certain Weakly Reversible Mappings
Bao She WEI
2002-01-01
In this paper, we consider certain mappings, M, sufficiently close to an integrable one,which is weakly reversible with respect to the mappings G sufficiently close to an involution of type(m, n), where m,n ∈ Z+ are arbitrary. Under some weak non-degeneracy condition, we constructa uniform KAM iteration for proving the existence of a Cantor family of m-tori invariant under thereversible mappings M and the reversing mapping G.
Quasi-periodicity in relative quasi-periodic tori
Fassò, Francesco; García-Naranjo, Luis C.; Giacobbe, Andrea
2015-10-01
At variance from the cases of relative equilibria and relative periodic orbits of dynamical systems with symmetry, the dynamics in relative quasi-periodic tori (namely, subsets of the phase space that project to an invariant torus of the reduced system on which the flow is quasi-periodic) is not yet completely understood. Even in the simplest situation of a free action of a compact and abelian connected group, the dynamics in a relative quasi-periodic torus is not necessarily quasi-periodic. It is known that quasi-periodicity of the unreduced dynamics is related to the reducibility of the reconstruction equation, and sufficient conditions for it are virtually known only in a perturbation context. We provide a different, though equivalent, approach to this subject, based on the hypothesis of the existence of commuting, group-invariant lifts of a set of generators of the reduced torus. Under this hypothesis, which is shown to be equivalent to the reducibility of the reconstruction equation, we give a complete description of the structure of the relative quasi-periodic torus, which is a principal torus bundle whose fibers are tori of a dimension which exceeds that of the reduced torus by at most the rank of the group. The construction can always be done in such a way that these tori have minimal dimension and carry ergodic flow.
A 12-coil superconducting 'bumpy torus' magnet facility for plasma research.
Roth, J. R.; Holmes, A. D.; Keller, T. A.; Krawczonek, W. M.
1972-01-01
A retrospective summary is presented of the performance of the two-coil superconducting pilot rig which preceded the NASA Lewis bumpy torus. The NASA Lewis bumpy torus facility consists of 12 superconducting coils, each with a 19 cm i.d. and capable of producing magnetic field strengths of 3.0 teslas on their axes. The magnets are equally spaced around a major circumference 1.52 m in diameter, and are mounted with the major axis of the torus vertical in a single vacuum tank 2.59 m in diameter. The design value of maximum magnetic field on the magnetic axis (3.0 T) has been reached and exceeded.
Toroidal magnet system conceptual design for the ELMO Bumpy Torus Reactor
Luton, Jr, J. N.; Yeh, H. T.
1977-01-01
The ELMO Bumpy Torus Reactor (EBTR) is a fusion reactor device based on the concept of toroidally linked mirrors. To minimize engineering uncertainties, the EBTR superconducting magnet system is designed so that it could be built with existing or near-term technology. The design uses identical coils in standard modules, thus facilitating commercialization. The reference design uses 48 modules and produces 4000 MW(th).
Oscillations of radiation pressure supported tori near black holes
Mazur, Grzegorz P.; Zanotti, Olindo; Sądowski, Aleksander; Mishra, Bhupendra; Kluźniak, Wlodek
2016-03-01
We study the dynamics of radiation pressure supported tori around Schwarzschild black holes, focusing on their oscillatory response to an external perturbation. Using KORAL, a general relativistic radiation-hydrodynamics code capable of modelling all radiative regimes from the optically thick to the optically thin, we monitor a sample of models at different initial temperatures and opacities, evolving them in two spatial dimensions for ˜165 orbital periods. The dynamics of models with high opacity is very similar to that of purely hydrodynamics models, and it is characterized by regular oscillations which are visible also in the light curves. As the opacity is decreased, the tori quickly and violently migrate towards the gas-pressure dominated regime, collapsing towards the equatorial plane. When the spectra of the L2 norm of the mass density are considered, high-frequency inertial-acoustic modes of oscillations are detected (with the fundamental mode at a frequency 68 M_BH^{-1} Hz), in close analogy to the phenomenology of purely hydrodynamic models. An additional mode of oscillation, at a frequency 129 M_BH^{-1} Hz, is also found, which can be unambiguously attributed to the radiation. The spectra extracted from the light curves are typically noisier, indicating that in a real observation such modes may not be easily detected.
Observation of hot-electron ring instabilities in ELMO Bumpy Torus
A high-frequency hot electron instability is observed in ELMO Bumpy Torus (EBT) plasmas when the hot electron-to-ion density ratio exceeds 0.4. Both the real frequency and the imaginary frequency are larger than the ion cyclotron frequency. The azimuthal mode number (m) is 7, and the instability rotates in the hot electron curvature drift direction. This instability is identified as a curvature-driven mode. When it is strongly excited, the equilibrium of the hot electron annuli and confined core plasmas are destroyed (disruption). Extensive ion heating and neutron bursts are associated with this instability
Greene’s residue criterion for the breakup of invariant tori of volume-preserving maps
Fox, Adam M.; Meiss, James D.
2013-01-01
Invariant tori play a fundamental role in the dynamics of symplectic and volume-preserving maps. Codimension-one tori are particularly important as they form barriers to transport. Such tori foliate the phase space of integrable, volume-preserving maps with one action and d angles. For the area-preserving case, Greene’s residue criterion is often used to predict the destruction of tori from the properties of nearby periodic orbits. Even though KAM theory applies to the three-dimensional case, the robustness of tori in such systems is still poorly understood. We study a three-dimensional, reversible, volume-preserving analogue of Chirikov’s standard map with one action and two angles. We investigate the preservation and destruction of tori under perturbation by computing the “residue” of nearby periodic orbits. We find tori with Diophantine rotation vectors in the “spiral mean” cubic algebraic field. The residue is used to generate the critical function of the map and find a candidate for the most robust torus.
REGIMUL JURIDIC AL BILETULUI DE CĂLĂTORIE ELECTRONIC
Dumitriţa BAEŞU
2016-03-01
Full Text Available În articol sunt scoase în relief principalele repere conceptuale ce se ataşează problematicii cu privire la coraportul biletului de călătorie electronic în transportul auto de călători şi bagaje şi în transportul aerian. Este fundamentată teza, potrivit căreia sistemul de taxare electronic în cadrul prestării serviciilor de transport este deosebit de important şi necesar în contextul racordării legislaţiei naţionale la cerinţele Uniunii Europene. De asemenea, se menţionează că reforma în cazul respectiv este oportună şi inevitabilă, deoarece una dintre condiţiile cerute de Uniunea Europeană pentru integrarea Republicii Moldova în acest sistem constă în armonizarea legislaţiei privind transportul la standardele europene. Nu în ultimul rând, este formulată concluzia, potrivit căreia achiziţionarea biletelor de călătorie electronice a devenit mult mai comodă, economă şi accesibilă. LEGAL REGIME OF THE ELECTRONIC TRAVEL TICKET In the article are pointed out major conceptual aspects that are a added to issues on the ticket correlation of road transport of passengers electronic ticket and luggage in air transport. It is fundamental thesis that the electronic toll system in transport services is particularly important and necessary in the context of adjusting the national legislation to the European Union standards. Also in this case, is mentioned that reform is appropriate and inevitable, because one of the conditions required by the EU for Moldova's integration into the system is to harmonize transport legislation with European standards. Finally, as conclusion, electronic travel ticket purchasing has become more convenient, cheap and affordable.
A vast amount of various invariant tori in the Nosé-Hoover oscillator
Wang, Lei [School of Mathematics and Statistics, Huazhong University of Science and Technology, Wuhan 430074 (China); Department of Mathematics and Physics, Hefei University, Hefei 230601 (China); Yang, Xiao-Song, E-mail: yangxs@hust.edu.cn [School of Mathematics and Statistics, Huazhong University of Science and Technology, Wuhan 430074 (China)
2015-12-15
This letter restudies the Nosé-Hoover oscillator. Some new averagely conservative regions are found, each of which is filled with different sequences of nested tori with various knot types. Especially, the dynamical behaviors near the border of “chaotic region” and conservative regions are studied showing that there exist more complicated and thinner invariant tori around the boundaries of conservative regions bounded by tori. Our results suggest an infinite number of island chains in a “chaotic sea” for the Nosé-Hoover oscillator.
A 12 coil superconducting bumpy torus magnet facility for plasma research
Roth, J. R.; Holmes, A. D.; Keller, T. A.; Krawczonek, W. M.
1972-01-01
A summary is presented of the performance of the two-coil superconducting pilot rig which preceded the NASA Lewis bumpy torus. This pilot rig was operated for 550 experimental runs over a period of 7 years. The NASA Lewis bumpy torus facility consists of 12 superconducting coils, each with a 19 cm in diameter and capable of producing magnetic field strengths of 3.0 teslas on their axes. The magnets are equally spaced around a major circumference 1.52 m in diameter, and are mounted with the major axis of the torus vertical in a single vacuum tank 2.59 m in diameter. The design value of maximum magnetic field on the magnetic axis (3.0 teslas) was reached and exceeded. A maximum magnetic field of 3.23 teslas was held for a period of 60 minutes, and the coils did not go to normal. When the coils were charged to a maximum magnetic field of 3.35 teslas, the coil system was driven normal without damage to the facility.
Cheng, Qiang; Wang, Jian; Zhang, Shaoan
2013-01-01
Guided by cultural border crossing and teacher identity development theories, this case study explores the bumpy process of a junior Chinese faculty member's border crossing into the U.S. teaching culture and analyzes the challenges, coping strategies, and consequences of his border crossing on teaching and teacher identity development. The…
Nonsymmetric systems arising in the computation of invariant tori
Trummer, M.R. [Simons Fraser Univ., Burnaby, British Columbia (Canada)
1996-12-31
We introduce two new spectral implementations for computing invariant tori. The underlying nonlinear partial differential equation although hyperbolic by nature, has periodic boundary conditions in both space and time. In our first approach we discretize the spatial variable, and find the solution via a shooting method. In our second approach, a full two-dimensional Fourier spectral discretization and Newton`s method lead to very large, sparse, nonsymmetric systems. These matrices are highly structured, but the sparsity pattern prohibits the use of direct solvers. A modified conjugate gradient type iterative solver appears to perform best for this type of problems. The two methods are applied to the van der Pol oscillator, and compared to previous algorithms. Several preconditioners are investigated.
Low-energy capture of asteroids onto KAM tori
Verrier, Patricia E
2015-01-01
We present a new method for engineering the artificial capture of asteroids. Based on theories of the chaos-assisted capture of natural satellites of the giant planets, we show how an unbound asteroid that passes close to a regular region of phase space can be easily moved onto the nearby KAM tori and essentially permanently captured with the Earth's Hill sphere without closing the zero velocity curves. The method has the advantages of a relatively low delta-v requirement and no need for control strategies. An illustration of the method is given for an example asteroid trajectory, demonstrating that it is a viable strategy for the final capture stage of asteroids in the Earth's neighbourhood.
Constructive spherical codes on layers of flat tori
Torezzan, Cristiano; Vaishampayan, Vinay A
2012-01-01
A new class of spherical codes is constructed by selecting a finite subset of flat tori from a foliation of the unit sphere S^{2L-1} of R^{2L} and designing a structured codebook on each torus layer. The resulting spherical code can be the image of a lattice restricted to a specific hyperbox in R^L in each layer. Group structure and homogeneity, useful for efficient storage and decoding, are inherited from the underlying lattice codebook. A systematic method for constructing such codes are presented and, as an example, the Leech lattice is used to construct a spherical code in R^{48}. Upper and lower bounds on the performance, the asymptotic packing density and a method for decoding are derived.
Dynamical supersymmetry breaking on magnetized tori and orbifolds
Abe, Hiroyuki; Sumita, Keigo
2016-01-01
We construct several dynamical supersymmetry breaking (DSB) models within a single ten-dimensional supersymmetric Yang-Mills (SYM) theory, compactified on magnetized tori with or without orbifolding. We study the case that the supersymmetry breaking is triggered by a strong dynamics of $SU(N_C)$ SYM theory with $N_F$ flavors contained in the four-dimensional effective theory. We show several configurations of magnetic fluxes and orbifolds, those potentially yield, below the compactification scale, the field contents and couplings required for triggering DSB. We especially find a class of self-complete DSB models on orbifolds, where all the extra fields are eliminated by the orbifold projection and DSB successfully occurs within the given framework. Comments on some perspectives for associating the obtained DSB models with the other sectors, such as the visible sector and another hidden sector for, e.g., stabilizing moduli, are also given.
The existence of periodic orbits and invariant tori for some 3-dimensional quadratic systems.
Jiang, Yanan; Han, Maoan; Xiao, Dongmei
2014-01-01
We use the normal form theory, averaging method, and integral manifold theorem to study the existence of limit cycles in Lotka-Volterra systems and the existence of invariant tori in quadratic systems in ℝ(3). PMID:24982980
Lax representation for two-particle dynamics splitting on two tori
Enolskii, V Z; Enolskii, Victor; Salerno, Mario
1996-01-01
Lax representation in terms of 2\\times 2 matrices is constructed for a separable multiply--periodic system splitting on two tori. Hyperelliptic Kleinian functions and their reduction to elliptic functions are used.
Martin, Charles Francis James
The Ontario Tories' 42-year hegemony in government (1943-1985) was wrought through clever policies which often utilized Crown institutions to promote prosperity or to oblige or mollify vying interests. Ousted in 1985, though, they used their time in opposition to revise the Tory doctrine. In the 1995 election, the Tories emerged a tougher, more truculent group quite unlike their predecessors. Campaigning on their Common Sense Revolution (CSR) platform, they promised to eliminate red tape and vowed to obliterate all ostensible economic barriers which were impeding commerce in the province. In the CSR, the Tories identified Ontario Hydro (OH), the province's lauded publicly-owned power monopoly, as a troublesome and inefficient Crown entity which required fundamental reform. Portions of OH, they hinted, would likely be sold. Once elected, the Tories worked hurriedly to demolish OH and destroy public power in Ontario. For nearly 100 years, OH proved a pivotal component within the province's political economy for its provision of affordable, reliable power and its function as a policy tool to incite and direct development. A Tory government fought to instigate public power in the early 1900s and, in the late 1900s, a Tory government was fighting vigorously to rescind it. Why would they now renounce Crown power? It is the intent of this thesis to elucidate the Tory government's involvement in the transformation of Ontario's electricity industry from 1995 to 2003. Distinguishing electricity as a special, strategic staple, this thesis uses a pro-state, pro-staples industry political economy approach to discern how and why the Tory government sought to restructure the electricity sector. Essentially, it posits that the onslaught of neoliberalism, the emergence of novel generating technology, and the faltering of OH's nuclear wing all had a huge part to play in provoking the Tory government to initiate its reforms. Their reforms, though, proved too hasty, haughty, and
Excitation of lower-hybrid waves by the rf heating of Elmo Bumpy Torus scale
The substantial ion heating of toroidal plasmas at rf frequencies between the ion-cyclotron and lower-hybrid frequencies suggests that some additional process or processes must supplement conventional harmonic ion-cyclotron coupling of wave energy to particles. It is proposed in this paper that superthermal lower-hybrid turbulence excited because of the harmonic oscillating two-stream instability could contribute in a significant way to this observed heating. The threshold field strength for such a process to occur in the Elmo Bumpy Torus scale is calculated. Specific tests of the theory, measurement of an enhanced lower-hybrid and quasimode spectrum, particularly at harmonics of the pump frequency, are indicated. The impact of the harmonic oscillating two-stream instability as allowing rf heating at frequencies a factor of 2 or 3 below the lower-hybrid frequency is described
Staircase model for magnetohydrodynamic spectrum and global instabilities in the Elmo bumpy torus
In the staircase model a continuous equilibrium is approximated by a discontinuous one with jump surfaces separating regions of constant pressure, density, and magnetic rotation number. The dispersion relation, giving the growth rates or frequencies of eigenmodes of the linearized motion as solutions of a finite matrix eigenvalue problem, is derived for arbitrary axisymmetric straight staircase equilibria with no azimuthal magnetic field and with weak, long, and thin periodic mirrors. This relation is shown to describe global modes accurately, thus being well suited to obtaining their dependence upon the pressure and density profile with minimal numerical effort. Application to hollow pressure profiles typical of the Elmo bumpy torus yields global instabilities with growth rates too large to be compatible with observations, indicating that kinetic effects must be invoked to explain even the large-scale behavior of this device
Nuclear performance calculations for the ELMO Bumpy Torus Reactor (EBTR) reference design
The nuclear performance of the ELMO Bumpy Torus Reactor reference design has been calculated using the one-dimensional discrete ordinates code ANISN and the latest available ENDF/B-IV transport cross-section data and nuclear response functions. The calculated results include estimates of the spatial and integral heating rate with emphasis on the recovery of fusion neutron energy in the blanket assembly and minimization of the energy deposition rates in the cryogenic magnet coil assemblies. The tritium breeding ratio in the natural lithium-laden blanket was calculated to be 1.29 tritium nuclei per incident neutron. The radiation damage in the reactor structural material and in the magnet assembly is also given
Electron temperature measurements from induced toroidal current in ELMO Bumpy Torus-Scale
We have carried out measurements on ELMO Bumpy Torus-Scale (EBT-S) to estimate the electron temperature of the toroidal plasma by inducing a small (approx. 2-A) fluctuating (5-Hz) ac toroidal current. The modulating frequency used is low enough to minimize the effects of cavity skin time (approx. 100 ms) and plasma inductance. We have calculated the temperature from the measured values of the current obtained by use of the Rogowsky loop at various fill pressures at 100 kW with 28-GHz operation. The electron temperature has been estimated to be around 80 to 90 eV with an error of about 10 to 25% in the low T-mode, which is in good agreement with the Thomson scattering measurements
Study of plasma confinement in ELMO Bumpy Torus with a heavy-ion beam probe
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
MHD phenomena and transport of energetic ions in spherical tori
Experiments on Spherical Tori (ST) show that plasma MHD activity may strongly deteriorate the confinement of energetic ions. Therefore, a study of the interplay of MHD modes and energetic ions is of large practical importance. Such a study is carried out in this work, where both the influence of the energetic ions on plasma MHD activity and the MHD-induced transport of energetic ions are considered. In particular, it is shown that in STs, in contrast to conventional tokamaks, the presence of trapped energetic ions may have a destabilizing influence on the ideal kink instability and the collisionless tearing instability. On the other hand, it is found the transport of energetic ions caused by reconnection events (sawtooth oscillations, internal reconnection events and non-ideal fishbones) has a number of peculiarities in STs. Specific calculations of the change of the neutron flux caused by the particle redistribution by reconnection events and of the loss fraction of the energetic ions are carried out for the Neutral Beam Injected (NBI) ions in the National Spherical Torus Experiment (NSTX). Results of the calculations are compared with experimental observations. (author)
AGN Dusty Tori: II. Observational Implications of Clumpiness
Nenkova, Maia; Nikutta, Robert; Ivezic, Zeljko; Elitzur, Moshe
2008-01-01
From extensive radiative transfer calculations we find that clumpy torus models with \\No \\about 5--15 dusty clouds along radial equatorial rays successfully explain AGN infrared observations. The dust has standard Galactic composition, with individual cloud optical depth \\tV \\about 30--100 at visual. The models naturally explain the observed behavior of the 10\\mic silicate feature, in particular the lack of deep absorption features in AGN of any type. The weak 10\\mic emission feature tentatively detected in type 2 QSO can be reproduced if in these sources \\No drops to \\about 2 or \\tV exceeds \\about 100. The clouds angular distribution must have a soft-edge, e.g., Gaussian profile, the radial distribution should decrease as $1/r$ or $1/r^2$. Compact tori can explain all observations, in agreement with the recent interferometric evidence that the ratio of the torus outer to inner radius is perhaps as small as \\about 5--10. Clumpy torus models can produce nearly isotropic IR emission together with highly anisotr...
M-theory FDA, twisted tori and Chevalley cohomology
The FDA algebras emerging from twisted tori compactifications of M-theory with fluxes are discussed within the general classification scheme provided by Sullivan's theorems and by Chevalley cohomology. It is shown that the generalized Maurer-Cartan equations which have appeared in the literature, in spite of their complicated appearance, once suitably decoded within cohomology, lead to trivial FDAs, all new p-form generators being contractible when the 4-form flux is cohomologically trivial. Non-trivial D=4 FDAs can emerge from non-trivial fluxes but only if the cohomology class of the flux satisfies an additional algebraic condition which appears not to be satisfied in general and has to be studied for each algebra separately. As an illustration an exhaustive study of Chevalley cohomology for the simplest class of SS algebras is presented but a general formalism is developed, based on the structure of a double elliptic complex, which, besides providing the presented results, makes possible the quick analysis of compactification on any other twisted torus
M-theory FDA, twisted tori and Chevalley cohomology
Fre, Pietro [Dipartimento di Fisica Teorica, Universita di Torino, INFN, Sezione di Torino, via P. Giuria 1, I-10125 Turin (Italy)]. E-mail: fre@to.infn.it
2006-05-15
The FDA algebras emerging from twisted tori compactifications of M-theory with fluxes are discussed within the general classification scheme provided by Sullivan's theorems and by Chevalley cohomology. It is shown that the generalized Maurer-Cartan equations which have appeared in the literature, in spite of their complicated appearance, once suitably decoded within cohomology, lead to trivial FDAs, all new p-form generators being contractible when the 4-form flux is cohomologically trivial. Non-trivial D=4 FDAs can emerge from non-trivial fluxes but only if the cohomology class of the flux satisfies an additional algebraic condition which appears not to be satisfied in general and has to be studied for each algebra separately. As an illustration an exhaustive study of Chevalley cohomology for the simplest class of SS algebras is presented but a general formalism is developed, based on the structure of a double elliptic complex, which, besides providing the presented results, makes possible the quick analysis of compactification on any other twisted torus.
The Oak Ridge National Laboratory Radially Resolved Time-Dependent One-Dimensional Transport code is described. The physical models and numerical techniques incorporated to follow the time evolution of ELMO Bumpy Torus plasmas ranging in size from the present experiment to power reactors are discussed. Sample input/output files are presented, and instructions for use on the Oak Ridge DEC-10 and the National Magnetic Fusion Energy Computer Center CRAY systems are given
The prevalence of tori amongst constant mean curvature planes in R3
Carberry, Emma; Schmidt, Martin Ulrich
2016-08-01
Constant mean curvature (CMC) tori in Euclidean 3-space are described by an algebraic curve, called the spectral curve, together with a line bundle on this curve and a point on S1, called the Sym point. For a given spectral curve the possible choices of line bundle and Sym point are easily described. The space of spectral curves of tori is totally disconnected. Hence to characterise the "moduli space" of CMC tori one should, for each genus g, determine the closure Pg bar of spectral curves of CMC tori within the spectral curves of CMC planes having spectral genus g. We identify a real subvariety Rg and a subset Sg ⊆Rg such that Rmaxg ⊆Pg bar ⊆Sg, where Rmaxg denotes the points of Rg having maximal dimension. The lowest spectral genus for which tori exist is g = 2 and in this case R2 = Rmax2 =P2 bar =S2. For g > 2, we conjecture that Rg ⊋ Rmaxg =Sg. We give a number of alternative characterisations of Rmaxg and in particular introduce a new integer invariant of a CMC plane of finite type, called its winding number.
Computation of whiskered invariant tori and their associated manifolds: new fast algorithms
Huguet, Gemma; Sire, Yannick
2010-01-01
In this paper we present efficient algorithms for the computation of several invariant objects for Hamiltonian dynamics. More precisely, we consider KAM tori (i.e diffeomorphic copies of the torus such that the motion on them is conjugated to a rigid rotation) both Lagrangian tori (of maximal dimension) and whiskered tori (i.e. tori with hyperbolic directions which, together with the tangents to the torus and the symplectic conjugates span the whole tangent space). In the case of whiskered tori, we also present algorithms to compute the invariant splitting and the invariant manifolds associated to the splitting. We present them both for the case of discrete time and for differential equations. The algorithms are based on a Newton method to solve an appropriately chosen functional equation that expresses invariance. The algorithms are efficient: if we discretize the objects by $N$ elements, one step of the Newton method requires only O(N) storage and $O(N \\ln(N))$ operations. Furthermore, if the object we cons...
Spherical tori (ST), represented mainly by the spherical tokamak, are of growing importance for fusion research, and several new devices are planned or under construction around the world. The purpose of the Joint Meeting was to provide a forum for discussion of approaches to fusion energy based on ST. Other toroidal configurations, such as low aspect ratio helical systems and spheromaks, were also included in the scope of this meeting
Efficient Indirect All-to-All Personalized Communication on Rings and 2-D Tori
GU Naijie
2001-01-01
All-to-All personalized communication is a basic communication operation in a parallel computing environment. There are a lot of results appearing in literature. All these communication algorithms can be divided into two kinds: direct communication algorithm and indirect communication algorithm. The optimal direct all-to-all communication algorithm on rings and 2-D tori does exist. But, for indirect all-to-all communication algorithms, there is a gap between the time complexity of the already existing algorithm and the lower bound. In this paper an efficient indirect algorithm for all-to-all communication on rings and 2-D square tori with bidirection channels is presented. The algorithms is faster than any previous indirect algorithms. The main items of the time complexity of the algorithm is p2/8 and pa/2/8 on rings and 2-D tori respectively, both reaching the theoretical lower bound, where p is the number of processors.
Clumpy tori around type II active galactic nuclei as revealed by X-ray fluorescent lines
Liu, Jiren; Liu, Yuan; Li, Xiaobo; Xu, Weiwei; Gou, Lijun; Cheng, Cheng
2016-06-01
The reflection spectrum of a torus around an active galactic nucleus (AGN) is characterized by X-ray fluorescent lines, which are most prominent for type II AGNs. A clumpy torus allows photons reflected from the back-side of the torus to leak through the front regions that are free of obscuration. The observed X-ray fluorescent lines are therefore sensitive to the clumpiness of the torus. We analysed a sample of type II AGNs observed with the Chandra High Energy Transmission Grating Spectrometer (HETGS), and measured the fluxes for the Si Kα and Fe Kα lines. The measured Fe Kα/Si Kα ratios, spanning a range between 5 and 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. We compared the measured Fe Kα/Si Kα ratios with simulation results of clumpy tori. The Circinus galaxy has a Fe Kα/Si Kα ratio of ˜60, 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 Kα/Si Kα ratios of the other sources are all below the simulation results for N = 2. Overall, this shows that the non-Fe fluorescent lines in the soft X-ray band are a potentially powerful probe of the clumpiness of tori around AGNs.
The perpendicular energy component of the stored energy of the electron annuli in ELMO Bumpy Torus (EBT) can be observed with diamagnetic flux detecting coils. The calibration of the signal from the coils in terms of stored energy requires a model for the geometrical structure of the annulus. Using a model of concentric cylindrical current sheets, the calibration factor for the diamagnetic perpendicular energy signal is derived, including the effects of drift currents and coupling of flux from adjacent annuli. Numerical calculations show the calibration factor to be insensitive to reasonable variations in the model parameters
Conformal chiral boson models on twisted doubled tori and non-geometric string vacua
Avramis, Spyros D; Prezas, Nikolaos
2009-01-01
We derive and analyze the conditions for quantum conformal and Lorentz invariance of the duality symmetric interacting chiral boson sigma-models, which are conjectured to describe non-geometric string theory backgrounds. The one-loop Weyl and Lorentz anomalies are computed for the general case using the background field method. Subsequently, our results are applied to a class of (on-shell) Lorentz invariant chiral boson models which are based on twisted doubled tori. Our findings are in agreement with those expected from the effective supergravity approach, thereby firmly establishing that the chiral boson models under consideration provide the string worldsheet description of N=4 gauged supergravities with electric gaugings. Furthermore, they demonstrate that twisted doubled tori are indeed the doubled internal geometries underlying a large class of non-geometric string compactifications. For compact gaugings the associated chiral boson models are automatically conformal, a fact that is explained by showing ...
On Invariant Tori of Nearly Integrable Hamiltonian Systems with Quasiperiodic Perturbation
Cheng Rong
2010-01-01
Full Text Available We are concerned with the persistence of frequency of invariant tori for analytic integrable Hamiltonian system with quasiperiodic perturbation. It is proved that if the unperturbed system satisfies the Rüssmann's nondegeneracy condition and has nonzero Brouwer's topological degree at some Diophantine frequency; the perturbed system satisfies the colinked nonresonant condition, then the invariant torus with this frequency persists under quasiperiodic perturbation.
Equilibria of charged dust tori in a dipole magnetic field: hydrodynamic approach
Slaný, P.; Kovář, J.; Stuchlík, Z.; Karas, Vladimír
Opava : Silesian University, 2014 - (Stuchlík, Z.), s. 221-227 ISBN 9788075101266. ISSN 2336-5668. - (Publications of the Institute of Physics. 7). [RAGtime /14.-16./. Opava (CZ), 18.09.2012-22.09.2012] R&D Projects: GA ČR GB14-37086G Institutional support: RVO:67985815 Keywords : dust tori * electric charge * magnetic field Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics
Charged perfect fluid tori in strong central gravitational and dipolar magnetic fields
Kovář, Jiří; Slaný, Petr; Cremaschini, Claudio; Stuchlík, Zdeněk; Karas, Vladimír; Trova, Audrey
2016-06-01
We study electrically charged perfect fluid toroidal structures encircling a spherically symmetric gravitating object with Schwarzschild spacetime geometry and endowed with a dipole magnetic field. The work represents a direct continuation of our previous general-relativistic studies of electrically charged fluid in the approximation of zero conductivity, which formed tori around a Reissner-Nordström black hole or a Schwarzschild black hole equipped with a test electric charge and immersed in an asymptotically uniform magnetic field. After a general introduction of the zero-conductivity charged fluid model, we discuss a variety of possible topologies of the toroidal fluid configurations. Along with the charged equatorial tori forming interesting coupled configurations, we demonstrate the existence of the off-equatorial tori, for which the dipole type of magnetic field seems to be necessary. We focus on orbiting structures with constant specific angular momentum and on those in permanent rigid rotation. We stress that the general analytical treatment developed in our previous works is enriched here by the integrated form of the pressure equations. To put our work into an astrophysical context, we identify the central object with an idealization of a nonrotating magnetic neutron star. Constraining ranges of its parameters and also parameters of the circling fluid, we discuss a possible relevance of the studied toroidal structures, presenting along with their topology also pressure, density, temperature and charge profiles.
Roth, J. R.
1976-01-01
Parametric variation of independent variables which may affect the characteristics of bumpy torus plasma have identified those which have a significant effect on the plasma current, ion kinetic temperature, and plasma number density, and those which do not. Empirical power law correlations of the plasma current, and the ion kinetic temperature and number density were obtained as functions of potential applied to the midplane electrode rings, the background neutral gas pressure, and the magnetic field strength. Additional parameters studied included the type of gas, the polarity of the midplane electrode rings, the mode of plasma operation, and the method of measuring the plasma number density. No significant departures from the scaling laws appear to occur at the highest ion kinetic temperatures or number densities obtained to date.
Doubly twisted Neimark-Sacker bifurcation and two coexisting two-dimensional tori
Sekikawa, Munehisa; Inaba, Naohiko
2016-01-01
We discuss a complicated bifurcation structure involving several quasiperiodic bifurcations generated in a three-coupled delayed logistic map where a doubly twisted Neimark-Sacker bifurcation causes a transition from two coexisting periodic attractors to two coexisting invariant closed circles (ICCs) corresponding to two two-dimensional tori in a vector field. Such bifurcation structures are observed in Arnol'd tongues. Lyapunov and bifurcation analyses suggest that the two coexisting ICCs and the two coexisting periodic solutions almost overlap in the two-parameter bifurcation diagram.
Lower dimensional invariant tori with prescribed frequency for nonlinear wave equation
Geng, Jiansheng; Ren, Xiufang
In this paper, one-dimensional (1D) nonlinear wave equation u-u+mu+u=0, subject to Dirichlet boundary conditions is considered. We show that for each given m>0, and each prescribed integer b>1, the above equation admits a Whitney smooth family of small-amplitude quasi-periodic solutions with b-dimensional Diophantine frequencies, which correspond to b-dimensional invariant tori of an associated infinite-dimensional dynamical system. In particular, these Diophantine frequencies are the small dilation of a prescribed Diophantine vector. The proof is based on a partial Birkhoff normal form reduction and an improved KAM method.
Tori Amos 《American Doll Posse》闪亮出炉
Karen
2007-01-01
最近,Tori Amos的新专辑《American Doll Posse》问世。虽然她去年发行了精选集,但这张专辑是2005年《the Beekeeper》以来的首张录音室作品。专辑发行的同时,Amos将踏上世界巡演的路程,5月28日的巡演第一站设在罗马。
The outside of the Teichmuller space of punctured tori in Maskit's embedding
Parkkonen, Jouni
1996-01-01
We consider the following question: Which parameters in the extension of a rational pleating ray across the boundary of $\\Cal M$, the Maskit embedding of the Teichm\\"uller space of once punctured tori correspond to a Kleinian group? Using methods of Keen and Series and Wright we prove a local result, stating that on each rational ray there is a sequence of parameters in $\\overline\\Bbb H\\setminus\\Cal M$ accumulating at the boundary point of $\\Cal M$ on the ray. These are the unique parameters ...
Twisted tori and fluxes: A no go theorem for Lie groups of weak G2 holonomy
In this paper we prove the theorem that there exists no 7-dimensional Lie group manifold G of weak G2 holonomy. We actually prove a stronger statement, namely that there exists no 7-dimensional Lie group with positive definite Ricci tensor RicIJ. This result rules out (supersymmetric and non-supersymmetric) Freund-Rubin solutions of M-theory of the form AdS4xG and compactifications with non-trivial 4-form fluxes of Englert type on an internal group manifold G. A particular class of such backgrounds which, by our arguments are excluded as bulk supergravity compactifications corresponds to the so-called compactifications on twisted tori, for which G has structure constants τKIJ with vanishing trace τJIJ=0. On the other hand our result does not have bearing on warped compactifications of M-theory to four dimensions and/or to compactifications in the presence of localized sources (D-branes, orientifold planes and so forth). Henceforth our result singles out the latter compactifications as the preferred hunting grounds that need to be more systematically explored in relation with all compactification features involving twisted tori
Noriyosi Sato
Full Text Available To improve the effectiveness of tori-lines it is necessary to evaluate the ability of tori-lines to mitigate seabird bycatch and determine what kind of seabird species gather during line settings, attack the bait and are incidentally caught. We conducted two experiments in the western North Pacific and examined the effectiveness for seabird mitigation of light streamer tori-lines which have no long streamers but many light (short streamers and are mainly used in the North Pacific area. Firstly, the effectiveness of two different types of tori-line (light streamer (1 m and long streamer (up to 7 m tori-line and of two different colors (yellow and red of light streamers for seabird bycatch avoidance was evaluated using 567 sets based on data from 20 offshore surface commercial longliners. No significant difference in the bycatch number between the different tori-line types and streamer colors was found. Secondly, we investigated the characteristics of the seabird bycatch in the North Pacific and the effectiveness of three different types of streamers (light, hybrid and modified light types by detailed observations of seabird attacks using a chartered longline vessel. Although the appearance rate of albatrosses and shearwaters were 40.9% and 27.7%, Laysan albatross was the main seabird species that followed the vessel but shearwaters seldom followed the vessel and did not aggregate during line setting. In all attacks on bait observed during line settings, 81% and 7% were by albatrosses and shearwaters, respectively. In the number of primary attacks by Laysan albatrosses which attacked most aggressively of all seabirds, there were no significant differences among the tori-line types. No individuals of shearwater were caught. The results of both experiments indicated that light streamer tori-lines were as effective as tori-lines with long streamers for mitigating seabird bycatch in the North Pacific.
Power balance in ELMO Bumpy Torus: bulk electrons and ions in a 37 kW discharge
McNeill, D.H.
1985-10-01
The power balance of the bulk electrons and ions in discharges with 37 kW of applied microwave power in the ELMO Bumpy Torus (EBT) is examined in a zero-dimensional model using data on the intensity and linewidth of the molecular and atomic hydrogen emission. At least 60% of the applied power is ultimately dissipated by processes involving the neutral particles, including dissociation of molecules, ionization of and radiation from atoms, and heating of cold electrons produced during atomic ionization. The molecular influx rate and the density of atoms are used independently to determine the bulk electron particle confinement time, and an upper bound estimate is made of the diffusional power loss from the bulk plasma electrons. Parameters derived from the basic spectroscopic data presented in this paper include the neutral atom density 2 - 5x10/sup 10/ cm/sup -3/, incident molecular flux 3 - 5x10/sup 15/ cm/sup -2/s/sup -1/, bulk ion temperature approx. =3 eV, and particle confinement time <1.1 ms. The bulk electron energy confinement time is 0.7 ms or less in the standard operating regime. Published data on the nonthermal electron and ion populations in the plasma are used to evaluate approximately the overall energy flow in the discharge. 54 refs.
Power balance in ELMO Bumpy Torus: bulk electrons and ions in a 37 kW discharge
The power balance of the bulk electrons and ions in discharges with 37 kW of applied microwave power in the ELMO Bumpy Torus (EBT) is examined in a zero-dimensional model using data on the intensity and linewidth of the molecular and atomic hydrogen emission. At least 60% of the applied power is ultimately dissipated by processes involving the neutral particles, including dissociation of molecules, ionization of and radiation from atoms, and heating of cold electrons produced during atomic ionization. The molecular influx rate and the density of atoms are used independently to determine the bulk electron particle confinement time, and an upper bound estimate is made of the diffusional power loss from the bulk plasma electrons. Parameters derived from the basic spectroscopic data presented in this paper include the neutral atom density 2 - 5x1010 cm-3, incident molecular flux 3 - 5x1015 cm-2s-1, bulk ion temperature approx. =3 eV, and particle confinement time <1.1 ms. The bulk electron energy confinement time is 0.7 ms or less in the standard operating regime. Published data on the nonthermal electron and ion populations in the plasma are used to evaluate approximately the overall energy flow in the discharge. 54 refs
Simulations of flux variability of oscillating accretion fluid tori around Kerr black holes
Bakala, Pavel; Šrámková, Eva; Kotrlová, Andrea; Török, Gabriel; Vincent, Frederic H; Abramowicz, Marek A
2014-01-01
High frequency quasi-periodic oscillations (HF QPOs) are observed in the X-ray power-density spectra (PDS) of several microquasars and low mass X-ray binaries. Many proposed QPO models are based on oscillations of accretion toroidal fluid structures orbiting in the vicinity of a compact object. We study oscillating accretion tori orbiting in the vicinity of a Kerr black hole. We demonstrate that significant variation of the observed flux can be caused by the combination of radial and vertical oscillation modes of a slender, polytropic, perfect fluid, non-self-graviting torus with constant specific angular momentum. We investigate two combinations of the oscillating modes corresponding to the direct resonance QPO model and the modified relativistic precession QPO model.
Luque, Alejandro; Villanueva, Jordi
2016-06-01
We present a numerical method for computing initial conditions of Lagrangian quasi-periodic invariant tori of Hamiltonian systems and symplectic maps. Such initial conditions are found by solving, using the Newton method, a nonlinear system obtained by imposing suitable conditions on the frequency map. The basic tool is a newly developed methodology to perform the frequency analysis of a discrete quasi-periodic signal, allowing to compute frequencies and their derivatives with respect to parameters. Roughly speaking, this method consists in computing suitable weighted averages of the iterates of the signal and using the Richardson extrapolation method. The proposed approach performs with high accuracy at a moderate computational cost. We illustrate the method by considering a discrete FPU model and the vicinity of the point L4 in a RTBP.
Shaghaghian, M
2016-01-01
We examine a thick accretion disc in the presence of external gravity and intrinsic dipolar magnetic field due to a non-rotating central object. In this paper, we generalize the Newtonian theory of stationary axisymmetric resistive tori of Tripathy, Prasanna $\\&$ Das (1990) by including the fully general relativistic features. If we are to obtain the steady state configuration, we have to take into account the finite resistivity for the magnetofluid in order to avoid the piling up of the field lines anywhere in the accretion discs. The efficient value of conductivity must be much smaller than the classical conductivity to be astrophysically interesting. The accreting plasma in the presence of an external dipole magnetic field gives rise to a current in the azimuthal direction. The azimuthal current produced due to the motion of the magnetofluid modifies the magnetic field structure inside the disc and generates a poloidal magnetic field for the disc. The solutions we have found show that the radial inflow...
Deformations on tilted tori and moduli stabilisation at the orbifold point
Blaszczyk, Michael; Honecker, Gabriele; Koltermann, Isabel
2015-11-01
We discuss deformations of orbifold singularities on tilted tori in the context of Type IIA orientifold model building with D6-branes on special Lagrangian cycles. Starting from {T}^6/({{Z}}_2× {{Z}}_2) , we mod out an additional {{Z}}_3 symmetry to describe phenomenologically appealing backgrounds and reduce to {{Z}}_3 and Ω R invariant orbits of deformations. While D6-branes carrying SO(2 N) or USp(2 N) gauge groups do not constrain deformations, D6-branes with U( N) gauge groups develop non-vanishing D-terms if they couple to previously singular, now deformed cycles. We present examples for both types of D6-branes, and in a three-generation Pati-Salam model on {T}^6/({{Z}}_2× {{Z}}_6^') we find that ten out of 15 twisted complex structure moduli are indeed stabilised at the orbifold point by the existence of the brane stacks.
A KAM theorem without action-angle variables for elliptic lower dimensional tori
We study elliptic lower dimensional invariant tori of Hamiltonian systems via parametrizations. The method is based on solving iteratively the functional equations that stand for invariance and reducibility. In contrast with classical methods, we do not assume that the system is close to an integrable one nor that it is written in action-angle variables. We only require an approximation of an invariant torus with a fixed vector of basic frequencies and a basis along the torus that approximately reduces the normal variational equations to constant coefficients. We want to highlight that this approach presents many advantages compared with methods which are built in terms of canonical transformations, e.g., it produces simpler and more constructive proofs that lead to more efficient numerical algorithms for the computation of these objects. Such numerical algorithms are suitable to be adapted in order to perform computer assisted proofs
Neoclassical plasma viscosity and transport processes in non-axisymmetric tori
Shaing, K. C.; Ida, K.; Sabbagh, S. A.
2015-11-01
Neoclassical transport processes are important to the understanding of plasma confinement physics in doubly periodic magnetized toroidal plasmas, especially, after the impact of the momentum confinement on the particle and energy confinement is recognized. Real doubly periodic tori in general are non-axisymmetric, with symmetric tori as a special case. An eight-moment approach to transport theory with plasma density N, plasma pressure p, mass flow velocity V and heat flow q as independent variables is adopted. Transport processes are dictated by the solutions of the momentum and heat flux balance equations. For toroidal plasma confinement devices, the first order (in the gyro-radius ordering) plasma flows are on the magnetic surface to guarantee good plasma confinement and are thus two-dimensional. Two linearly independent components of the momentum equation are required to determine the flows completely. Once this two-dimensional flow is relaxed, i.e. the momentum equation reaches a steady state, plasmas become ambipolar, and all the transport fluxes are determined through the flux-force relation. The flux-force relation is derived both from the kinetic definitions for the transport fluxes and from the manipulation of the momentum and heat flux balance equations to illustrate the nature of the transport fluxes by examining their corresponding driven forces and their roles in the momentum and heat flux balance equations. Steady-state plasma flows are determined by the components of the stress and heat stress tensors in the momentum and heat flux balance equations. This approach emphasizes the pivotal role of the momentum equation in the transport processes and is particularly useful in modelling plasma flows in experiments. The methodology for neoclassical transport theory is applied to fluctuation-driven transport fluxes in the quasilinear theory to unify these two theories. Experimental observations in tokamaks and stellarators for the physics discussed are
Mihaela Veţan; Sergiu Florean
2012-01-01
Parteneriatele de solidaritate ASAT sunt dezvoltate în România începând cu anul 2008, în vederea susţinerii micilor producători agricoli care cultivă natural. Dezvoltarea acestora este susţinută la nivel naţional de Asociaţia Centrul de Resurse pentru Iniţiative Eticeși Solidare (CRIES). Mecanismul este unul bazat pe construirea unui relaţii de încredere între producători locali şi consumatori urbani. Astfel,se formează la nivel comunitar grupuri de consumatori care doresc să achiziţioneze pr...
2007-01-01
Women who perform popular music are also performing gender. This is both because gender can be understood as performance and because musical conventions and styles carry with them assumptions about femininity and masculinity. This thesis concerns three female popular music artists; Kim Gordon of Sonic Youth, Tori Amos and Gillian Welch, and their performances of femininity. As these artists have been presented as or have presented themselves as in some way "authentic", my readings of these ar...
A preliminary numerical study of flux penetration dynamics has been made assuming a bumpy cylinder geometry for the EBT vacuum vessel. Estimates made by this study show that the diamagnetic signal from the rings should penetrate the vacuum vessel in a time on the order of 100 mS when the plasma is changed. This penetration time appears qualitatively reasonable
Development of Instruments onboard ASTRO-H for Future X-ray Studies of Tori
Noda, H.
2015-09-01
The next astronomical X-ray satellite ASTRO-H will be launched by Japan Aerospace eXploration Agency (JAXA) in this Japanese fiscal year. It allows us to combine a simultaneous coverage of the 0.4-600 keV band, and a high energy-resolution spectroscopy in the 0.3-12 keV band with an FWHM energy resolution of coating hard X-ray mirrors, and a non-focusing soft gamma-ray detector covers the 40-600 keV band. The high energy-resolution spectroscopy is realized by the X-ray micro-calorimeter array operated at 50 mK on a focal plane of the soft X-ray telescope. With the unprecedented performances, the ASTRO-H observations of active galactic nuclei are expected to give us important X-ray information about tori including their dynamics, size, ionization state and so on. In the present talk, we introduce the current status of developments of the instruments onboard ASTRO-H, especially focusing on the performance of the X-ray micro-calorimeter derived in the ongoing ground testing and calibration.
Lie tori of type B_2 and graded-simple Jordan structures covered by a triangle
Neher, Erhard
2011-01-01
We classify two classes of B_2-graded Lie algebras which have a second compatible grading by an abelian group A: (a) graded-simple Lie algebras for A torsion-free and (b) division-A-graded Lie algebras. Our results describe the centreless cores of a class of affine reflection Lie algebras, hence apply in particular to the centreless cores of extended affine Lie algebras, the so-called Lie tori, for which we recover results of Allison-Gao and Faulkner. Our classification (b) extends a recent result of Benkart-Yoshii. Both classifications are consequences of a new description of Jordan algebras covered by a triangle, which correspond to these Lie algebras via the Tits-Kantor-Koecher construction. The Jordan algebra classifications follow from our results on graded-triangulated Jordan triple systems. They generalize work of McCrimmon and the first author as well as the Osborn-McCrimmon-Capacity-2-Theorem in the ungraded case.
Properties of dusty tori in active galactic nuclei - II. Type 2 AGN
Hatziminaoglou, Evanthia; Jarrett, Tom
2009-01-01
(abridged) This paper is the second part of a work investigating the properties of dusty tori in AGN by means of multi-component SED fitting. It focuses on low luminosity, low redshift (z < 0.25) AGN selected among emission line galaxies as well as X-ray, radio and mid-infrared selected type 2 AGN samples from the literature. The available multi-band photometry covers the spectral range from the u-band up to 160 um. The observed SED of each object is fit to a set of multi-component models comprising a stellar component, a high optical depth torus and cold emission from a starburst (SB). The contribution of the various components (stars, torus, SB) is reflected in the position of the objects on the IRAC colour diagram. The comparison of type 1 (as derived from Hatziminaoglou et al. 2008) and type 2 AGN properties is broadly consistent with the Unified Scheme. The estimated ratio between type 2 and type 1 objects is about 2-2.5:1. The AGN accretion-to-infrared luminosity ratio is an indicator of the obscurat...
Kardiostimulátory a zdroje rušení
Lojková, Lea
2009-01-01
Tématem této semestrální práce jsou kardiostimulátory a zdroje rušení. Projekt částečně navazuje na starší diplomovou práci na dané téma (Ing. Kulík, Ústav automatizace a měřicí techniky FEKT, VUT Brno) a z hlediska metodiky měření rozvíjí dané téma podobným směrem. Teoretická část práce stručně vysvětluje principy nukleární magnetické rezonance a magnetické tomografie, popisuje nejběžnější metody používané při magnetické tomografii, definuje kardiostimulátor, uvádí hlavní milníky v jeho vývo...
This report describes the fabrication and tests of a tangentially imaging soft X-ray (SXR) camera diagnostic for fusion energy plasma research. It can be used for the determination of the current distribution in strongly shaped toroidal magnetically confined plasmas, such as those found in spherical tori or advanced tokamaks. It included the development of both an appropriate imaging SXR camera and image analysis techniques necessary to deduce the plasma shape and current distribution. The basic camera concept consists of a tangentially viewing pinhole imaging system with thin-film SXR filters, a scintillator screen to provide SXR to visible conversion, a fast shuttering system, and an sensitive visible camera imaging device. The analysis approach consists of integrating the 2-D SXR image data into a Grad-Shafranov toroidal equilibrium solver code to provide strong constraints on the deduced plasma current and pressure profiles. Acceptable sensitivity in the deduced current profile can be obtained if the relative noise in the measured image can be kept in the range of 1% or less. Tests on the Pegasus Toroidal Experiment indicate very flat safety factor profiles in the plasma interior
Deformations on Tilted Tori and Moduli Stabilisation at the Orbifold Point
Blaszczyk, Michael; Koltermann, Isabel
2015-01-01
We discuss deformations of orbifold singularities on tilted tori in the context of Type IIA orientifold model building with D6-branes on special Lagrangian cycles. Starting from $T^6/(\\mathbb{Z}_2 \\times \\mathbb{Z}_2)$, we mod out an additional $\\mathbb{Z}_3$ symmetry to describe phenomenologically appealing backgrounds and reduce to $\\mathbb{Z}_3$ and $\\Omega\\mathcal{R}$ invariant orbits of deformations. While D6-branes carrying SO(2N) or USp(2N) gauge groups do not constrain deformations, D6-branes with U(N) gauge groups develop non-vanishing D-terms if they couple to previously singular, now deformed cycles. We present examples for both types of D6-branes, and in a three-generation Pati-Salam model on $T^6/(\\mathbb{Z}_2 \\times \\mathbb{Z}_6')$ we find that ten out of 15 twisted complex structure moduli are indeed stabilised at the orbifold point by the existence of the brane stacks.
Mesh theory of angle modified dual tori double-enveloping toroidal worm drive
无
2010-01-01
In this paper, the meshing theory of the angle modified hourglass worm drive is enriched and developed. The ordinary condition of the angle modification is derived and the physical significance of the modification is interpreted. A normal section methodology is proposed for meshing analysis, which can be used to compute the normal distance near a singular meshing point of a conjugate surface couple. By means of the method and after analyzing the normal transversals, it is specified that the worm helicoid, the nominal former contact zone and the new contact zone intersect each other along the locus of singular points of the instantaneous contact lines of an angle-modified worm pair. As a result, it is explained clearly that those three osculate each other but the osculations are different in degree. Moreover, the mechanism of removing the twice-contacted zone from the worm gear tooth surface is clarified and the reason of shortening the worm working length is also elucidated. With the help of the theory described in the present paper and the thorough and systematic research on the relevant meshing characteristics, the angle modified dual tori double-enveloping toroidal worm drive has been shown to be an excellent new-fashioned hourglass worm set.
Radiation-driven Outflows from and Radiative Support in Dusty Tori of Active Galactic Nuclei
Chan, Chi-Ho; Krolik, Julian H.
2016-07-01
Substantial evidence points to dusty, geometrically thick tori obscuring the central engines of active galactic nuclei (AGNs), but so far no mechanism satisfactorily explains why cool dust in the torus remains in a puffy geometry. Near-Eddington infrared (IR) and ultraviolet (UV) luminosities coupled with high dust opacities at these frequencies suggest that radiation pressure on dust can play a significant role in shaping the torus. To explore the possible effects of radiation pressure, we perform three-dimensional radiative hydrodynamics simulations of an initially smooth torus. Our code solves the hydrodynamics equations, the time-dependent multi–angle group IR radiative transfer (RT) equation, and the time-independent UV RT equation. We find a highly dynamic situation. IR radiation is anisotropic, leaving primarily through the central hole. The torus inner surface exhibits a break in axisymmetry under the influence of radiation and differential rotation; clumping follows. In addition, UV radiation pressure on dust launches a strong wind along the inner surface; when scaled to realistic AGN parameters, this outflow travels at ˜ 5000 {(M/{10}7{M}ȯ )}1/4 {[{L}{UV}/(0.1{L}{{E}})]}1/4 {km} {{{s}}}-1 and carries ˜ 0.1 {(M/{10}7{M}ȯ )}3/4 {[{L}{UV}/(0.1{L}{{E}})]}3/4 M ⊙ yr‑1, where M, {L}{UV}, and {L}{{E}} are the mass, UV luminosity, and Eddington luminosity of the central object respectively.
Toris K Silicone Hydrogel Contact Lens for the Optical Management of Keratoconus
1, Leyla YAVUZ; 2, İhsan YILMAZ; 1, Özlen Rodop ÖZGÜR; 1, Baran KANDEMİR; 1, Ümit CALLI; 1, Cemalettin CABI
2013-01-01
Amaç: Keratokonus hastalarının görsel rehabilitasyonunda Toris K silikon hidrojel lensinin etkinliğini değerlendirmek. Materyal ve Metot: Retrospektif çalışmaya 58 hastanın 100 gözü dahil edildi. Hastaların ortalama yaşı 27,04± 9,5 yaş idi ve 15 göz grade 1, 28 göz grade 2, 13 göz grade 3, 44 göz grade 4 keratokonus idi. Düzeltilmemiş en iyi görme keskinliği, gözlükle düzeltilmiş en iyi görme keskinliği, korneal topografik ölçümler ve pakimetrik değerler kayıt edildi. Ortalama korneal kırıcı...
Toroidal orbifolds of Z3 and Z6 symmetries of noncommutative tori
Walters, Sam
2015-05-01
The Hexic transform ρ of the noncommutative 2-torus Aθ is the canonical order 6 automorphism defined by ρ (U) = V, ρ (V) =e-πiθU-1 V, where U, V are the canonical unitary generators obeying the unitary Heisenberg commutation relation VU =e2πiθ UV . The Cubic transform is κ =ρ2. These are canonical analogues of the noncommutative Fourier transform, and their associated fixed point C*-algebras Aθρ, Aθκ are noncommutative Z6, Z3 toroidal orbifolds, respectively. For a large class of irrationals θ and rational approximations p / q of θ, a projection e of trace q2 θ - pq is constructed in Aθ that is invariant under the Hexic transform. Further, this projection is shown to be a matrix projection in the sense that it is approximately central, the cut down algebra eAθ e contains a Hexic invariant q × q matrix algebra M whose unit is e and such that the cut downs eUe, eVe are approximately inside M. It is also shown that these invariant matrix projections are covariant in that they arise from a continuous section E (t) of C∞-projections of the continuous field {At } 0 algebras such that ρ (E (t)) = E (t). It turns out that the projection E (t) is the support projection of a canonical C∞-positive element that has the appearance of a noncommutative 2-dimensional Theta function. The topological invariants (or 'quantum' numbers) of E (t), e, and related projections are computed by a new and quicker method than in previous works. (They would also give topological invariants for finitely generated projective modules over noncommutative orbifolds associated to Z6 and Z3 symmetries of noncommutative tori.) We remark that these results have some bearing on research work related to noncommutative orbifolds used in string theory.
Shaghaghian, M.
2016-02-01
We examine a thick accretion disc in the presence of external gravity and intrinsic dipolar magnetic field due to a non-rotating central object. In this paper, we generalize the Newtonian theory of stationary axisymmetric resistive tori of Tripathy, Prasanna & Das by including the fully general relativistic features. If we are to obtain the steady state configuration, we have to take into account the finite resistivity for the magnetofluid in order to avoid the piling up of the field lines anywhere in the accretion discs. The efficient value of conductivity must be much smaller than the classical conductivity to be astrophysically interesting. The accreting plasma in the presence of an external dipole magnetic field gives rise to a current in the azimuthal direction. The azimuthal current produced due to the motion of the magnetofluid modifies the magnetic field structure inside the disc and generates a poloidal magnetic field for the disc. The solutions we have found show that the radial inflow, pressure and density distributions are strongly modified by the electrical conductivity both in relativistic and Newtonian regimes. However, the range of conductivity coefficient is different for both regimes, as well as that of the angular momentum parameter and the radius of the innermost stable circular orbit. Furthermore, it is shown that the azimuthal velocity of the disc which is not dependent on conductivity is sub-Keplerian in all radial distances for both regimes. Owing to the presence of pressure gradient and magnetic forces. This work may also be important for the general relativistic computational magnetohydrodynamics that suffers from the lack of exact analytic solutions that are needed to test computer codes.
Deviations from this ideal geometry and less-than-perfect alignment of the field coils in an ELMO Bumpy Torus generate perturbations to the ideal magnetic field configuration, resulting generally in failure of the field lines to close on themselves and thereby causing degradation in plasma confinement. The sensitivity of the field line displacement to certain types of errors in coil parameters is studied by means of a perturbation formalism developed for an action integral representing the longitudinal adiabatic invariant. Reflection symmetry properties satisfied by the magnetic field and the vector potential are derived, and it is demonstrated both analytically and numerically that the leading term of the field line displacement per period of 2π around the major axis is second order in the perturbation parameter if the coil planes remain invariant under the perturbation. Numerical analyses for the field line displacement also reveal some more useful properties for the first- and second-order terms in the perturbation series
Yilmaz, Ihsan; Ozcelik, Ferah; Basarir, Berna; Demir, Gokhan; Durusoy, Gonul; Taskapili, Muhittin
2016-01-01
Objectives. To evaluate the visual performance of Toris K soft contact lenses in patients with moderate-to-advanced keratoconus and also to compare the results according to cone types, cone location, and severity of keratoconus. Materials and Methods. Sixty eyes of 40 participants were included in this retrospective study. Uncorrected visual acuity (UCVA), best-spectacle corrected visual acuity (BCVA), best-contact lens corrected visual acuity (BCLCVA), and comfort rating via visual analogue scales (VAS) were measured. Results. The mean age was 27.3 ± 8.6 years (range: 18 to 54). The mean logMAR UCVA, BCVA, and BCLCVA were 0.85 ± 0.38 (range: 0.30–1.30), 0.47 ± 0.27 (range: 0.10–1.30), and 0.16 ± 0.20 (range: 0–1.00). There were significant increases in visual acuities with contact lenses (p < .05). BCLCVA was significantly better in oval type than globus type (p = .022). UCVA and BCLCVA were significantly better in moderate keratoconus group (p = .015, p = .018). The mean line gain in Snellen was 3.6 ± 1.8 lines (range: 0–7 lines). The mean line gain was higher in central cone group than paracentral cone group and oval group than globus group (p = .014, p = .045). The mean VAS score was 8.14 ± 1.88 (range: 6–10). Conclusions. Toris K can improve visual acuity of patients with keratoconus. Toris K is successful even in the moderate and advanced form of the disease. PMID:27144012
Flux-force relation, a fundamental relation that relates transport fluxes to forces, for non-axisymmetric tori in general magnetic flux coordinates that are not Hamada coordinates, is derived. The derivation is based on kinetic theory instead of fluid theory. It is shown that pressure force also contributes to the relation in non-Hamada coordinates in general to make the relation compatible with kinetic theory and to make it coordinates invariant. The results are applied to the theory for the neoclassical toroidal viscosity in tokamaks that have error fields or resistive magnetohydrodynamic (MHD) modes.
Trova, A; Slany, P; Kovar, J
2016-01-01
We present an analytical approach for the equilibrium of a self-gravitating charged fluid embedded in a spherical gravitational and dipolar magnetic fields produced by a central mass. Our scheme is proposed, as a toy-model, in the context of gaseous/dusty tori surrounding supermassive black holes in galactic nuclei. While the central black hole dominates the gravitational field and it remains electrically neutral, the surrounding material has a non-negligible self-gravitational effect on the torus structure. By charging mechanisms it also acquires non-zero electric charge density, so the two influences need to be taken into account to achieve a self-consistent picture. With our approach we discuss the impact of self-gravity, represented by the term dt (ratio of the torus total mass to the mass of the central body), on the conditions for existence of the equilibrium and the morphology and typology of the tori. By comparison with a previous work without self-gravity, we show that the conditions can be different...
Mihaela Veţan
2012-10-01
Full Text Available Parteneriatele de solidaritate ASAT sunt dezvoltate în România începând cu anul 2008, în vederea susţinerii micilor producători agricoli care cultivă natural. Dezvoltarea acestora este susţinută la nivel naţional de Asociaţia Centrul de Resurse pentru Iniţiative Eticeși Solidare (CRIES. Mecanismul este unul bazat pe construirea unui relaţii de încredere între producători locali şi consumatori urbani. Astfel,se formează la nivel comunitar grupuri de consumatori care doresc să achiziţioneze produse realizate de mici agricultori, cu care încheie un contract pe perioada unui sezon agricol și cărora le plătesc un avans, în vederea susţinerii costurilor de producţie.
Mattsson, Anna
2009-01-01
This degree project aim to evaluate if variations of the STFI thickness can be used to assess bumpiness on cardboard. During the project cardboard samples were measured using Bendtsen, PPS, a L&W formation tester, OptiTopo, Ambertec formation, the STFI thickness tester and a visual comparison. The different methods were then compared to see if there is any correlations between them. The results showed that the visual comparison and OptiTopo correlates. The STFI thickness tester shows however ...
Zakrzewski, J.; Saini, S.; Taylor, H.S.
1988-10-15
A general theoretical base and a general strategy for implementing semiclassical quantization using the adiabatic-switching method are presented for two-dimensional systems. The method proposed does not depend on specialized coordinates, trajectory, or surfaces-of-section studies and is generalizable to multidimensional systems. The choice of the initial tori for the switching procedure is accomplished by simple diagonalizations of small-dimensional matrix representations of invariant operators obtained from perturbation theory. The method gives quantum energies at a useful level of accuracy for the vast majority of states in many of the well-known nonresonant and resonant Hamiltonian cases. Many eigenvalues previously thought unobtainable when the adiabatic-switching method is used are obtained in a quite simple manner.
The bumpy cylinder MHD equilibrium code which was compared to the concentric current sheet model for the EBT electron rings in a previous report has been subjected to additional numerical tests which confirm the validity of the previous work. Further analysis of the current sheet model as a means of calibration of the EBT diamagnetic diagnostic for perpendicular energy shows the model's simplicity is not the limiting factor in accuracy of the calibration. The fluctuations of the currents in the vacuum field coils were observed as voltage signals from the generator shunts. Significant low frequency components were observed that cannot be removed from diamagnetic signals by low pass filtering alone. A YIG magnetometer was developed and used to make test measurements of the diamagnetic field of the electron rings on EBT. The field values observed were on the order of 1 Gauss in a region where the vacuum field was about 600 Gauss. These values agree with the perpendicular energy diamagnetic flux diagnostic with reasonable assumptions for ring geometry
Use of multiple Hall effect probes is a cost effective way to observe diamagnetic fields from the hot electron rings in the Elmo Bumpy Torus device at several locations simultaneously. A special diagnostic instrument has been developed having six Hall probe channels with the sensitivity and stability needed for the diamagnetic measurements. The instrument uses an AC carrier system with isolation transformers located remotely from the instrument and near the probe locations. Details of instrument design as well as operating instructions for it are included in this report
X-ray bumps, iron K-alpha lines, and X-ray suppression by obscuring tori in Seyfert galaxies
Krolik, Julian H.; Madau, Piero; Zycki, Piotr T.
1994-01-01
We investigate the X-ray spectral properties of unobscured type 1 and obscured type 2 Seyferts as predicted by the unified Seyfert scheme. We consider the reprocessing of X-ray photons by photoelectric absorption, iron fluorescence, and Compton downscattering in the obscuring tori surrounding these active nuclei, and compute by Monte Carlo methods the reprocessed spectra as a function of the viewing angle. Depending on the optical depth and shape of the torus, and on the viewing angle, the X-ray flux can be suppressed by substantial factors when our line of sight is obscured. We show that an immediate consequence of the existence of an obscuring thick torus is the production in the spectra of type 1 Seyfert galaxies of a bump in the continuum above 10-20 keV and an Fe K-alpha line with significant equivalent width. In those type 2 Seyferts for which the hard X-ray spectrum has been substantially suppressed, the equivalent width of the Fe K-alpha line in the transmitted spectrum can be very large.
Poloidal potential in the low-collisionality regime in a nonaxisymmetric torus
The poloidal potential is calculated numerically in the low-collisionality regime for nonaxisymmetric tori such as stellarators and bumpy tori. It is found that even fairly deep into the superbanana regime, the poloidal potential retains the simple azimuthal dependence of the plateau regime. 12 refs., 8 figs
方萍; 李黎
2015-01-01
三聚氰胺浸渍橡木薄单板贴面实木复合地板是参考三聚氰胺浸渍纸贴面生产工艺生产出的表面凹凸实木复合地板。使用三聚氰胺胶黏剂、固化剂、渗透剂、脱膜剂（配比为500：1：1：1）混合液浸渍橡木薄单板，然后在真空度为0.08 MPa时保压浸渍5 min，在大气条件下放置30 min，取出后再放入90℃鼓风干燥箱中干燥10 min。浸渍完成的橡木薄单板与基材经热压成型为表面凹凸的实木复合地板。考虑热压温度、热压压力、热压时间对其凹凸表面成型的影响，每个因素取4个水平，制定因素水平表，选择正交表进行试验。对试验结果进行浸渍剥离及表面纹理深度的测量分析，得到最优的热压工艺条件为温度150℃、压力1.2 MPa、时间70 s。三聚氰胺浸渍的橡木贴面复合地板表面纹理、色泽、手感都更加接近自然。%Reference the producing technology of laminate floor,the hot-pressing of engineered floor which has bumpy sur-face overlaying with melamine formaldehyde resin(MF)impregnated oak veneer was studied. The oak veneer is dipped in the mixed liquor which has melamine formaldehyde resin,curing agent,penetrating agent,release agent(ratio of 500:1:1:1). After dipping 5 min when the vacuum degree is 0.08 MPa,it keeps 30 min in room conditions. Then dry 10 min in drying oven with temperature is 90 ℃.The impregnated oak veneer and ply wood as based of engineered flooring are put into the hot press under the different temperature,pressure and time to process shaping of its bumpy surface. The four levels of each fac-tor of hot- press is selected to investigate the effect on shaping of its bumpy surface in the experiment. Measured its dipping detachment and surface bumpy depth,the results shown that the optimum hot-pressing process conditions is temperature 150 ℃, the pressure 1.2 MPa,and time 70 s.
Leidenfrost levitated liquid tori
Perrard, Stéphane; Labousse, Matthieu; Fort, Emmanuel; Bush, John; Couder, Yves; Limat, Laurent
2012-11-01
A drop of water deposited on a surface hotter than 150°C can levitate without any contact with a solid container. Indeed the evaporation of the fluid generates a thin vapour film, which supports the drop's weight by lubrication forces (Leidenfrost effect). This effect was until now limited to droplets. We propose here an original substrate geometry, a circular brass through, that allows us to maintain in levitation any quantity of fluid. It could be a good tool to study wave propagation without solid boundary condition and thus very low friction. We report here one possible application, and our most striking observation : when the substrate temperature is high enough, convective motion appears in the liquid torus and its inner side becomes polygonal. This periodic deformation of large amplitude propagates along the azimuthal direction. The geometry, the flow and the shape appear very similar to the polygonal destabilization of an hydraulic jump. We propose here an experimental and theorical characterization of these rotating polygons having from three to twelve sides. Moreover, we have found a model describing the shape for any number of sides. It appears closely related to the Korteweg de Vries equation describing the propagation of solitonic waves in shallow water.
Feler, Yoel
2006-01-01
The configuration space C^n of unordered n-tuples of distinct points on a torus T^2 is a non-singular complex algebraic variety. We study holomorphic self-maps of C^n and prove that for n>4 any such map F either carries the whole of C^n into an orbit of the diagonal Aut(T^2) action in C^n or is of the form F(x)=T(x)x for some holomorphic map T:C^n-->Aut(T^2). We also prove that for n>4 any endomorphism of the torus braid group B_n(T^2) with a non-abelian image preserves the pure torus braid g...
Star Formation Black Hole Growth and Dusty Tori in the Most Luminous AGNs at z=2-3.5
Netzer, Hagai; Lani, Caterina; Nordon, Raanan; Trakhtenbrot, Benny; Lira, Paulina; Shemmer, Ohad
2016-03-01
We report Herschel/SPIRE observations of 100 very luminous, optically selected active galactic nuclei (AGNs) at z=2{--}3.5 with {log} {L}{{1350}} (erg s-1) ≥ 46.5 , where {L}{{1350}} is λLλ at 1350 Å. The distribution in {L}{{1350}} is similar to the general distribution of Sloan Digital Sky Survey AGNs in this redshift and luminosity interval. We measured star-formation (SF) luminosity, {L}{{SF}}, and SF rate (SFR) in 34 detected sources by fitting combined SF and torus templates, where the torus emission is based on Wide Field Infrared Survey Explorer observations. We also obtained statistically significant stacks for the undetected sources in two luminosity groups. The sample properties are compared with those of very luminous AGNs at z\\gt 4.5. The main findings are: (1) The mean and the median SFRs of the detected sources are {1176}-339+476 and {1010}-503+706 M⊙ yr-1, respectively. The mean SFR of the undetected sources is 148 M⊙ yr-1. The ratio of SFR to the black hole accretion rate is ≈80 for the detected sources and less than 10 for the undetected sources. Unlike a sample of sources at z ≃ 4.8 that we studied recently, there is no difference in {L}{{AGN}} and only a very small difference in {L}{{torus}} between the detected and undetected sources. (2) The redshift distribution of {L}{{SF}} and {L}{{AGN}} for the most luminous, redshift 2-7 AGNs are different. Similar to previous studies, the highest {L}{{AGN}} are found at z ≈ 3. However, the {L}{{SF}} of such sources peaks at z ≈ 5. Assuming the objects in our sample are hosted by the most massive galaxies at those redshifts, we find that approximately 2/3 of the hosts are already below the main sequence of SF galaxies at z = 2-3.5. (3) The spectral energy distributions (SEDs) of dusty tori at high redshift are similar to the shapes found in low redshift, low luminosity AGNs. Herschel upper limits put strong constraints on the long wavelength shape of the SED, ruling out several earlier
Pesando, Igor
2015-01-01
We consider the simplest possible setting of non abelian twist fields which corresponds to $SU(2)$ monodromies. We first review the theory of hypergeometric function and of the solutions of the most general Fuchsian second order equation with three singularities. Then we solve the problem of writing the general solution with prescribed $U(2)$ monodromies. We use this result to compute the classical string solution corresponding to three $D2$ branes in $R^4$. Despite the fact the configuration is supersymmetric the classical string solution is not holomorphic. Using the equation of motion and not the KLT approach we give a very simple expression for the classical action of the string. We find that the classical action is not proportional to the area of the triangle determined by the branes intersection points since the solution is not holomorphic. Phenomenologically this means that the Yukawa couplings for these supersymmetric configurations on non factorized tori are suppressed with respect to the factorized ...
Rahvapärane viiulimäng 20.sajandi esimesel poolel Tori ja Vändra viiuldajate näitel
Krista Sildoja
2011-12-01
Full Text Available The article gives an overview of the most well-known village fiddlers in Tori and Vändra parish, their repertoire, playing style and status as dance music players in the first half of the 20th century. This is one of the first efforts to try and describe Estonian traditional instrumental music from the inside so to say. First, the author learned to play the Estonian type of waltzes and polkas gathered from the local village musicians in her neighbourhood and used traditional method of learning by ear. Contact with the old fiddlers has been created artificially using the help of archive recordings datingback to the years 1936 and 1937. Following the personal experience of playing old fiddle tunes the author started transcribing and examining the tunes systematically.At that time both solo and duo performances were recorded from Tori and Vändra fiddlers. Those recordings compile the research material for the present article and on the basis of the recordings it is possible to describe how the fiddlers played back then. Transcriptions give an insight to the approach to form of the music and playing technique used in the fiddle tunes. Briefly, the body of those characteristics can be called the manner of playing the description of which introduces the musical thinking of village fiddlers and the overall characteristics of the performed music.What can be said to describe the traditional manner of playing based on the example of Tori and Vändra parish fiddlers? The districts of Tori and Vändra in the first half of the 20th century can be characterised by playing in fiddle duos. Compared to what was going on in Estonia of that time generally, it is not unique, because there were alsofiddle duos elsewhere. What is special about Tori and Vändra duos is how they wereplayed in. When playing in duos fiddlers used two different ways of playing. The first ofthem, one of the most characterising ones, is imitating bagpipe with fiddle, which wasonly used by
何文斌; 曾攀; 林峰; 颜永年; 张磊
2015-01-01
The bumpy ridge joining is the key technology of the heavy die forging press with steel wire wound. The shear resistance and the fatigue resistance of the bumpy ridge palr are vital to the integrity of the frame during service. The use of the technology is limited due to the deficient research on the principle of the bumpy ridge joining and the fatigue resistance of the structure. A set of clamp was developed to test the structural fatigue of the bumpy ridge joining, by which groups of fatigue tests of constant amplitude cycle tangential loading were performed.The cycle characteristic of the load-displacement of the bumpy ridge joining under the cycling tangential load is studied and the exponential model of the structural fatigue is established, the dimensionless fatigue load limit tmax*F is 0.74 when the load ratio R is 0.1. The relation between dimensionless amplitude value and mean value of the tangential load ( a mF*-F*) is studied to get the fatigue constant life curve, as well as a criterion of bumpy ridge structural damage accumulation is established based on Miner's theory. The safety evaluation and fatigue life prediction are implemented for the bumpy ridge structures of the heavy die forging press with steel wire wound.%剖分坎合是钢丝缠绕液压机的关键技术，坎合副的抗剪性及其抗疲劳性对模锻液压机使役期间保持机架完整性至关重要。坎合原理及抗疲劳性方面研究工作的不足限制了该技术的推广和应用。设计坎合疲劳试验夹具，对液压机本体小试样坎合结构进行切向等幅循环载荷疲劳试验。分析坎合结构切向循环载荷条件下三个阶段的载荷-位移循环特性；建立坎合结构疲劳指数模型，当载荷比R=0.1时，坎合结构疲劳量纲一载荷极限为Ft*max=0.74；研究量纲一切向载荷幅值与均值 a mF*-F*关系，得到坎合结构疲劳等寿命曲线；提出基于Miner线性累积损伤理论的坎合结构疲劳累积
Pesando, Igor
2016-09-01
We consider the simplest possible setting of non-abelian twist fields which corresponds to SU (2) monodromies. We first review the theory of hypergeometric function and of the solutions of the most general Fuchsian second order equation with three singularities. Then we solve the problem of writing the general solution with prescribed U (2) monodromies. We use this result to compute the classical string solution corresponding to three D2 branes in R4. Despite the fact that the configuration is supersymmetric the classical string solution is not holomorphic. Using the equation of motion and not the KLT approach we give a very simple expression for the classical action of the string. We find that the classical action is not proportional to the area of the triangle determined by the branes intersection points since the solution is not holomorphic. Phenomenologically this means that the Yukawa couplings for these supersymmetric configurations on non-factorized tori are suppressed with respect to the factorized case.
Design To Manufacturing Process:Bumpy Road?
2012-01-01
Ntegration between design and manufacturing is one of the topics that normally hits a lot of discussion in the product development and PLM space.To support this process becomes more and more important in a modern enterprise manufacturing organization.You can ask me why? Let me put is simple this is one of the most important processes that can drive cost optimization in the companies.Everything a company is making need to be first designed and later manufacturing.If it breaks nothing can help.
Test Structures For Bumpy Integrated Circuits
Buehler, Martin G.; Sayah, Hoshyar R.
1989-01-01
Cross-bridge resistors added to comb and serpentine patterns. Improved combination of test structures built into integrated circuit used to evaluate design rules, fabrication processes, and quality of interconnections. Consist of meshing serpentines and combs, and cross bridge. Structures used to make electrical measurements revealing defects in design or fabrication. Combination of test structures includes three comb arrays, two serpentine arrays, and cross bridge. Made of aluminum or polycrystalline silicon, depending on material in integrated-circuit layers evaluated. Aluminum combs and serpentine arrays deposited over steps made by polycrystalline silicon and diffusion layers, while polycrystalline silicon versions of these structures used to cross over steps made by thick oxide layer.
The bumpy road from renewable to sustainable
Solar energy is inherently renewable, but not automatically (fully) sustainable. Few people will disagree with this general statement, but that is about where consensus ends. Photovoltaic solar energy (PV) has rapidly left behind the megawatt-era and entered the gigawatt-era a few years ago. The PV sector is currently preparing for the 'real thing', i.e. the terawattscale manufacturing and installation that is needed for substantial impact on a global level. For that reason sustainability is now high on the list of development priorities, next to cost reduction and performance enhancement. Clearly terawatt-scale use is impossible, or at least undesirable, if certain sustainability criteria are not met. It would also severely affect the credibility of PV as a solution for sustainability related problems of society. The challenge is to translate this general concept into concrete actions that are useful for research, manufacturing, installation and other parts of the PV value chain. An important and famous definition of the concept of 'sustainability', or rather of 'sustainable development' has been given in the Brundtland Report: development that meets the needs of the present without compromising the ability of future generations to meet their own needs. Although this definition catches an essential aspect of 'sustainability', it does not give concrete leads for the difficult choices that have to be made in everyday life in general, and in solar energy technology development and deployment in particular. Many other, more specific definitions and descriptions have also been developed, especially related to the narrower term 'environmental sustainability'. Unfortunately, but not unexpectedly, these do not give final answers to the questions either. This leads to strong and sometimes emotional debates, but also to confusion and misunderstanding among specialists as well as non-specialists. Dealing with (or managing) these aspects of PV and using them to define the best development agenda, has become an important challenge for the PV sector. In the following report a few important aspects are discussed in some more detail.
Transport náboje v Ta2O5 oxidových nanovrstvách s aplikací na tantalové kondenzátory
Kopecký, Martin
2015-01-01
Studium transportu náboje v Ta2O5 oxidových nanovrstvách se zaměřuje především na objasnění vlivu defektů na vodivost těchto vrstev. Soustředíme se na studium oxidových nanovrstev Ta2O5 vytvořených pomocí anodické oxidace. Proces výroby Ta2O5 zahrnuje řadu parametrů, jež ovlivňují koncentraci defektů (oxidových vakancí) v této struktuře. Vrstva oxidu Ta2O5 o tloušťce 20 až 200 nm se často používá jako dielektrikum pro tantalové kondenzátory, které se staly nedílnou součástí elektrotechnického...
A qualitative identification of future engineering needs of alternative fusion concepts (AFCs) is presented. These needs are assessed relative to the similar needs of the tokamak in order to emphasize differences in required technology with respect to the well documented mainline approach. Although nearly thirty AFCs can be identified as being associated with some level of reactor projection, redirection, refocusing, and general similarities can be used to generate a reduced AFC list that includes only the bumpy tori, stellarators, reversed-field pinches, and compact toroids. Furthermore, each AFC has the potential of operating as a conventional (low power density, superconducting magnets) or a compact, high-power-density (HPD) system. Hence, in order to make tractable an otherwise difficult task, the future engineering needs for the AFCs are addressed here for conventional versus compact approaches, with the latter being treated as a generic class and the former being composed of bumpy tori, stellarators, reversed-field pinches, and compact toroids
Finite-Larmor-radius stability theory of EBT plasmas
An eikonal ballooning-mode formalism is developed to describe curvature-driven modes of hot electron plasmas in bumpy tori. The formalism treats frequencies comparable to the ion-cyclotron frequency, as well as arbitrary finite Larmor radius and field polarization, although the detailed analysis is restricted to E/sub parallel/ = 0. Moderate hot-electron finite-Larmor-radius effects are found to lower the background beta core limit, whereas strong finite-Lamor-radius effects produce stabilization
The strange rebirth of Tory England
Gamble, Andrew
2011-01-01
The Conservative party’s long dominance of British politics was overturned after 1992. The party suffered three consecutive election defeats, the first time this had happened in the modern era, and it seemed to lack the capacity to recover. After the 2005 defeat, however, the party under David Cameron has begun to seize back the political initiative from Labour. Cameron’s leadership is assessed against the background of the long Conservative hegemony, and the undermining of the five key pilla...
Non-planar string networks on tori
Type II strings in D=5 contain particle-like 1/8 supersymmetric BPS states. In this note we give a string-network representation of such states by considering (periodic) non-planar (p,q,r)-string networks of eight dimensional type II string theory on T3. We obtain the BPS mass formula of such states, in terms of charges and generating-vectors of the torus, and show its invariance under an SL(3, Z)XSL(3, Z) group of transformations. Results are then generalized to string-networks associated with the SL(5, Z) U-duality in seven dimensions. We also discuss reinterpretation of the above (D=5) mass formula in terms of BPS states in world-volume theories of U2-branes in D=8. (author)
TRANSIT OF EXOMOON PLASMA TORI: NEW DIAGNOSIS
In the solar system, moons largely exceed planets in number. The Kepler database has been shown to be sensitive to exomoon detection down to the mass of Mars, but the first search has been unsuccessful. Here, we use a particles-in-cell code to predict the transit of the plasma torus produced by a satellite. Despite the small size of a moon, the spatial extent of its plasma torus can be large enough to produce substantial transit absorptions. The model is used for the interpretation of Hubble Space Telescope early ingress absorptions apparently observed during the WASP-12 b and HD 189733 b UV transits for which no consistent explanation exists. For HD 189733 b an exomoon transiting ∼16 Rp ahead of the planet and loading ∼1029 C II ions s–1 into space is required to explain the tentative early ingress absorption observed for C II. For WASP-12b, a moon transiting ∼6 Rp ahead from the planet and ejecting ∼1028 Mg II ions per second is required to explain the NUV early ingress absorption feature. Interestingly, both HD 189733 b and WASP-12b predicted satellites are outside the Hill sphere of their planets, an indication that the moons, if present, were not formed in situ but probably captured later. Finally, our simulations show a strong electromagnetic coupling between the polar regions of planets and the orbital position of the moons, an expected outcome of the unipolar induction DC circuit model. Future observations should test our predictions with a potential opportunity to unambiguously detect the first exomoon plasma torus
Levi-Civita's Theorem for Noncommutative Tori
Jonathan Rosenberg
2013-11-01
Full Text Available We show how to define Riemannian metrics and connections on a noncommutative torus in such a way that an analogue of Levi-Civita's theorem on the existence and uniqueness of a Riemannian connection holds. The major novelty is that we need to use two different notions of noncommutative vector field. Levi-Civita's theorem makes it possible to define Riemannian curvature using the usual formulas.
Monodromy and isotopy of monotone Lagrangian tori
Yau, Mei-Lin
2008-01-01
We define new Hamiltonian isotopy invariants for a monotone Lagrangian torus embedded in a symplectic 4-manifold. We show that, in the standard symplectic 4-space, these invariants distinguish a monotone Clifford torus from a Chekanov torus.
Riemann surfaces and totally real tori
Duval, Julien; Gayet, Damien
2009-01-01
Given a generic totally real torus unknotted in the unit sphere of the complex plane, we prove the following alternative : either there exists a filling of the torus by holomorphic discs and the torus is rationally convex, or its rational hull contains a holomorphic annulus.
Vertex disjoint routings of cycles over tori
Bermond, Jean-Claude; Yu, Min-Li
2007-01-01
International audience We study the problem of designing a survivable WDM network based on covering the communication requests with subnetworks that are protected independently from each other. We consider here the case when the physical network is $T(n)$, a torus of size $n$ by $n$, the subnetworks are cycles and the communication scheme is all-to-all or total exchange (where all pairs of vertices communicate). We will represent the communication requests by a logical graph: a complete gr...
Twin tori for a new bundle divertor
A new bundle divertor system using the straight stagnation axis in toroidal field together with the uniform field along the axis is discussed in detail. We call this type of divertor as the ''muffler divertor'' because of its shape. (author)
Levi-Civita's Theorem for Noncommutative Tori
Jonathan Rosenberg
2013-01-01
We show how to define Riemannian metrics and connections on a noncommutative torus in such a way that an analogue of Levi-Civita's theorem on the existence and uniqueness of a Riemannian connection holds. The major novelty is that we need to use two different notions of noncommutative vector field. Levi-Civita's theorem makes it possible to define Riemannian curvature using the usual formulas.
Vávra, Jan
2011-01-01
The aim of the diploma thesis is to survey this niche market. The study was primary focused on software synthesizers. To evaluate the synthesizers a quantitative survey was done. Outputs of the survey resulted into specification of requirements for the software programmes for music composing and identification of respondents. The hypothesis concerning users of software synthesizers themselves was defined and evaluated by statistical methods. Following the hypothesis correlations between each ...
Jetela, Václav
2014-01-01
Bakalářská práce s názvem „Letecké aktuátory“ se v první části zabývá uceleným přehledem hydraulicky a elektricky poháněných aktuátorů používaných v letectví. Druhá část práce je věnována přehledu leteckých hydraulických okruhů. Jednotlivé kapitoly obsahují popis funkce a schémata. V následujících kapitolách práce jsou zpracovány návrhy testovacího standu pro zkoušení provozních parametrů aktuátorů. Závěr práce je věnován srovnání jednotlivých aktuátorů dle výkonu použití v letadlech....
TRANSIT OF EXOMOON PLASMA TORI: NEW DIAGNOSIS
Ben-Jaffel, Lotfi [UPMC, University of Paris 06, UMR 7095, Institut d' Astrophysique de Paris, F-75014 Paris (France); Ballester, Gilda E., E-mail: bjaffel@iap.fr, E-mail: gilda@pirl.lpl.arizona.edu [Lunar and Planetary Laboratory, University of Arizona, 1541 E. University Blvd, Tucson, AZ 85721-0063 (United States)
2014-04-20
In the solar system, moons largely exceed planets in number. The Kepler database has been shown to be sensitive to exomoon detection down to the mass of Mars, but the first search has been unsuccessful. Here, we use a particles-in-cell code to predict the transit of the plasma torus produced by a satellite. Despite the small size of a moon, the spatial extent of its plasma torus can be large enough to produce substantial transit absorptions. The model is used for the interpretation of Hubble Space Telescope early ingress absorptions apparently observed during the WASP-12 b and HD 189733 b UV transits for which no consistent explanation exists. For HD 189733 b an exomoon transiting ∼16 R{sub p} ahead of the planet and loading ∼10{sup 29} C II ions s{sup –1} into space is required to explain the tentative early ingress absorption observed for C II. For WASP-12b, a moon transiting ∼6 R{sub p} ahead from the planet and ejecting ∼10{sup 28} Mg II ions per second is required to explain the NUV early ingress absorption feature. Interestingly, both HD 189733 b and WASP-12b predicted satellites are outside the Hill sphere of their planets, an indication that the moons, if present, were not formed in situ but probably captured later. Finally, our simulations show a strong electromagnetic coupling between the polar regions of planets and the orbital position of the moons, an expected outcome of the unipolar induction DC circuit model. Future observations should test our predictions with a potential opportunity to unambiguously detect the first exomoon plasma torus.
Compression fractures of the vertebrae during a "bumpy" boat ride.
Chukwunyerenwa, C K
2012-01-31
INTRODUCTION: Compression fracture of the vertebrae is common, often the result of falls from height and motor vehicle accidents in the younger age groups. It can occur following minor trauma in the elderly and in those with osteoporosis. MATERIALS AND METHODS: We present an interesting case of compression fracture of the vertebral bodies occurring simultaneously in a couple during a boat ride while on holiday. One individual had fracture of the T8, while the other fractured the L1 vertebrae. Both injuries were treated conservatively with Taylor braces. CONCLUSION: We highlight one of the potential hazards of this recreational activity, and the almost identical fracture pattern in this couple.
Entropy production, viscosity bounds and bumpy black holes
Hartnoll, Sean A; Santos, Jorge E
2016-01-01
The ratio of shear viscosity to entropy density, $\\eta/s$, is computed in various holographic geometries that break translation invariance (but are isotropic). The shear viscosity does not have a hydrodynamic interpretation in such backgrounds, but does quantify the rate of entropy production due to a strain. Fluctuations of the metric components $\\delta g_{xy}$ are massive about these backgrounds, leading to $\\eta/s < 1/(4\\pi)$ at all finite temperatures (even in Einstein gravity). As the temperature is taken to zero, different behaviors are possible. If translation symmetry breaking is irrelevant in the far IR, then $\\eta/s$ tends to a constant at $T=0$. This constant can be parametrically small. If the translation symmetry is broken in the far IR (which nonetheless develops emergent scale invariance), then $\\eta/s \\sim T^{2 \
Theoretical studies of Elmo Bumpy Torus. Annual report
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
Confinement heating and stability in the ELMO Bumpy Torus (EBT)
The effects of heating methods, stability, neoclassical transport, nonadiabaticity, and ring power balance on the performance of an EBT reactor are discussed. Core plasma beta values in the range 10 to 15% have been estimated, but the reliability and importance of these estimates remain to be determined by future experiments and form a key objective for the EBT Proof-of-Principle (EBT-P) device. Potential variations on the basic EBT configuration that were expected to enhance reactor performance are discussed
Scare of Avian Flu Revisits India: A Bumpy Road Ahead
Rajnish Kumar Rai
2008-04-01
Full Text Available With the threat of an avian flu pandemic once again looming over eastern India, issues regarding patents and affordability and accessibility of drugs have taken center stage. The key priority of India should be to remain prepared to address the public health crisis effectively, by stockpiling the drug tamiflu so that it can be easily distributed and administered to the needy.India had been confronted with a serious threat of avian flu in 2005-06, but past experience shows that, despite having some of the broadest and most comprehensive compulsory patent licensing laws, India's policymaking elite shied away from fully exploiting these legal 'flexibilities.' Fortunately, the danger of avian flu did not turn into a substantial public health crisis that year. Under this backdrop, this paper explores various ‘flexibilities’ available in the Indian patent law and suggests short term and long term strategies to effectively tackle the impending danger of an avian flu pandemic, and similar public health crises in future. This paper will discuss potential areas of conflict between the indigenous generic drug firms and the multi-national companies with respect to TRIPS compliance in the event that these flexibilities are exploited. This paper also highlights the administrative constraints and the economic viability of the compulsory licensing system. Finally, this paper shows how political will is often more critical than having well documented provisions in statute books to respond to such situations effectively.
Understanding normal development of adolescent sexuality: A bumpy ride
Sujita Kumar Kar
2015-01-01
Full Text Available Adolescence, derived from the Latin word "adolescere" meaning "to grow up" is a critical developmental period. During adolescence, major biological as well as psychological developments take place. Development of sexuality is an important bio-psycho-social development, which takes an adult shape during this period. During adolescence, an individual′s thought, perception as well as response gets colored sexually. Puberty is an important landmark of sexuality development that occurs in the adolescence. The myriad of changes that occurs in adolescents puts them under enormous stress, which may have adverse physical, as well as psychological consequences. Understanding adolescent sexuality has important clinical, legal, social, cultural, as well as educational implications.
A successful international cooperation with a bumpy start
Ming Li
2011-01-01
Science has no boarders.The saying could not be more accurate in the case of infectious disease research.It is publicly known that infectious diseases can travel,not only through infected people,animals or insects,but also by commercial shipments.In the era of globalization,it is not possible to fight infectious diseases in one nation without worrying about what is happening elsewhere in the world.Emerging and re-emerging infectious diseases such as the outbreak of SARS in 2003 are likely to panic the Asian society at any time.To fight these diseases,the Chinese Academy of Sciences (CAS) and the University of Tokyo (UT) launched China-Japan Collaboration on Emerging and Re-emerging Infectious Diseases in 2005,as part of the Program of Founding Research Centers for Emerging and Re-emerging Infectious Diseases supported by Japan Ministry of Education,Science,Sports and Technology (MEXT).
The Big Bumpy Shift: Digital Music via Mobile Internet
Dolan, Daniel P.
2000-01-01
The promise and rise of mobile Internet technologies and markets will be remembered as one of the most profound global information technology developments of the next few years. Mobile Internet technologies and practical applications necessary for widespread public use are advancing rapidly in Japan and are likely to catch on quickly in other countries. The remarkable adoption of mobile Internet in Japan and the popularity of digital music file sharing services such as Napster in the United S...
Alternative approaches to plasma confinement
Roth, J. R.
1978-01-01
The paper discusses 20 plasma confinement schemes each representing an alternative to the tokamak fusion reactor. Attention is given to: (1) tokamak-like devices (TORMAC, Topolotron, and the Extrap concept), (2) stellarator-like devices (Torsatron and twisted-coil stellarators), (3) mirror machines (Astron and reversed-field devices, the 2XII B experiment, laser-heated solenoids, the LITE experiment, the Kaktus-Surmac concept), (4) bumpy tori (hot electron bumpy torus, toroidal minimum-B configurations), (5) electrostatically assisted confinement (electrostatically stuffed cusps and mirrors, electrostatically assisted toroidal confinement), (6) the Migma concept, and (7) wall-confined plasmas. The plasma parameters of the devices are presented and the advantages and disadvantages of each are listed.
Orientifold's landscape: non-factorisable six-tori
We construct type IIA orientifolds on T6/Z2 x Z2 which admit non factorisable lattices. We describe a method to deal with this kind of configurations and discuss how the compactification lattice affects the tadpole cancellation conditions. Moreover, we include D6-branes which are not parallel to O6-planes. These branes can give rise to chiral spectra in four dimensions, thus uncovering a new corner in the landscape of intersecting D-brane model constructions. We demonstrate the construction at an explicit example. In general we argue that obtaining an odd number of families is problematic
Charged Tori in Spherical Gravitational and Dipolar Magnetic Fields
Slaný, P.; Kovář, J.; Stuchlík, Z.; Karas, Vladimír
2013-01-01
Roč. 205, č. 1 (2013), 3/1-3/16. ISSN 0067-0049 R&D Projects: GA ČR(CZ) GC13-00070J Institutional support: RVO:67985815 Keywords : accretion * accretion disks * magnetic fields Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 14.137, year: 2013
Finite-temperature string theory and twisted tori
We show that the introduction of a finite temperature into string theory is mathematically equivalent to compactifying the timelike coordinate on a twisted torus of radius β/2π = 1/2πkT, the reciprocal of the temperature. We derive a general formula for the one-loop vacuum amplitude Λ(β) of a string theory compactified on a twisted torus that is manifestly modular invariant and is almost as easy to apply as in the compactification of a string theory on an ordinary torus. The connection with statistical mechanics is made through the formula lnZ(β) = -βVΛ(β) where Z(β) is the partition function and V the volume of the system. We discuss how the function σ(E) which counts the number of string states of total energy E and plays a central role in the microcanonical ensemble can be computed by taking the inverse Laplace transform of Z(β) and we give estimates of σ(E) for low and high energy densities by this method. We study the effect of finite temperature on the effective potentials for different parameters which determine a string theory's compactification. As supersymmetry is broken at finite temperature these potentials are nontrivial. We study the effect of finite temperature on the Wilson loop mechanism for gauge symmetry breaking and find that for a supersymmetric theory compactified on a torus finite-temperature effects favor the trivial vacuum. Also the effective potential for the radius R of the torus becomes modified so as to be minimum at R = 0 or R = ∞. The introduction of interactions and curvature effects into our formalism is discussed
MHD phenomena and transport of energetic ions in spherical tori
Mechanisms of the in the influence of MHD events on the beam ions in moderate-β plasmas relevant to current experiments on NSTX are studied. Change of the neutron yield caused by particle redistribution is evaluated. Destabilizing effect of the trapped energetic ions on ideal and non-ideal MHD modes in high-β plasmas is predicted. (author)
Radio frequency current drive for small aspect ratio tori
Non-inductive current drive (CD) is required during plasma initiation and for current sustainment in NSTX. The physics of high harmonic fast waves (HHFW) and the design of an antenna system for NSTX are studied. It is found that the theoretical current drive efficiency for HHFW can be high, and a general survey of parameters gives a good target for the antenna design. The primary issue for HHFW during plasma initiation is loading since the CD efficiency is very high for low density plasmas. For high beta operation at full current launching in the usual manner from the equatorial plane may lead to marginal CD performance. However, advanced antenna designs exploiting the theoretical results show some promise for high beta operation. Two methods to optimize the CD efficiency have been explored. The first non-zero poloidal mode excitation, provides enhanced efficiency because of improved penetration and a reduction of detrimental trapped particle effects. A second, placement of the antenna away from the equatorial plane, can also be used to reduce trapped particle effects. These methods can be used separately or together, yielding potential improvements of more than a factor of 2 in CD efficiency for NSTX
Radio Frequency Current Drive Considerations for Small Aspect Ratio Tori
Noninductive current drive is required during plasma initiation and for current sustainment in the National Spherical Torus Experiment (NSTX). In this paper, the physics of high harmonic fast waves (HHFW) and the design of an antenna system for NSTX are considered using numerical models. For high current discharges in NSTX, the static magnetic field component in the poloidal direction varies widely during the discharge and can become comparable to the toroidal component in NSTX. Therefore, they calculate the plasma loading for a broad range of antenna and plasma geometries in a three-dimensional model, so that the results can be used to influence the antenna design. Two-dimensional calculations of the wave propagation and absorption in the core plasma indicate that the theoretical current drive efficiency for HHFW can be high, and a general survey of parameters gives a good target for the antenna design. The current drive efficiency calculation is sensitive to the equilibrium model because finite beta effects can substantially alter the calculation of the trapped particle fraction. Traditional methods of toroidally phasing an antenna array as well as poloidal phasing are studied to optimize the current drive efficiency for a range of equilibria. Non-zero poloidal model excitation is also found to affect the antenna performance and flexibility. Performance expectations for a preliminary antenna design are given
AGN dust tori: the X-ray-infrared connection
Rowan-Robinson, Michael; Nandra, Kirpal
2009-01-01
We have combined the CLASX Chandra survey in Lockman with the Spitzer SWIRE survey data to study the X-ray-infrared connection for AGN. The sample consists of 401 X-ray-sources, of which 306 are detected by Spitzer, and a further 257 AGN candidates detected through their dust torus, but not by Chandra. For X-ray sources the X-ray hardness ratio has been modelled in terms of a power-law with absorption N(H). The optical and infrared data have been modelled in terms of our well-established optical galaxy and QSO templates, and infrared templates based on radiative transfer models. Our estimate of the N(H) distribution is consistent with other studies, but we do find a higher proportion of low absorption objects at z 0.5. While we find only one X-ray AGN with N(H) > 10^{24} cm^{-2}, we argue that 10 objects with torus luminosity apparently exceeding the bolometric X-ray to 3 \\mu m luminosity are strong candidates for being heavily absorbed in X-rays. We also estimate that at least half of the infrared-detected ...
Steroidní modulátory NMDA receptoru
Černý, Ivan; Pouzar, Vladimír; Chodounská, Hana
Ĺubochňa : Národný endokrinologický a diabetologický ústav v Ĺubochni, 2010. s. 22-22. [Imunoanalýza 2010. 14.06.2010-18.06.2010, Ĺubochňa] R&D Projects: GA MŠk(CZ) LC06077 Institutional research plan: CEZ:AV0Z40550506 Keywords : NMDA receptor * steroids Subject RIV: CC - Organic Chemistry
Teerullitaktika kasutamisest riigieelarve arutamisel aastail 1998-2005 / Erkki Tori
Tori, Erkki
2007-01-01
Autor analüüsib Riigikogu nelja koosseisu kogemusi riigieelarve menetlemisel ning jõuab järeldusele, et valitsuskoalitsioonid on kasutanud teerullitaktikat ning teeb selle vähendamiseks ettepaneku muuta menetlusreeglistikku. Tabelid: 1998-2005. aasta riigieelarvesse esitatud ettepanekute edukus. Diagrammid, graafikud
Curvature and geometric modules of noncommutative spheres and tori
Arnlind, Joakim
2014-04-01
When considered as submanifolds of Euclidean space, the Riemannian geometry of the round sphere and the Clifford torus may be formulated in terms of Poisson algebraic expressions involving the embedding coordinates, and a central object is the projection operator, projecting tangent vectors in the ambient space onto the tangent space of the submanifold. In this note, we point out that there exist noncommutative analogues of these projection operators, which implies a very natural definition of noncommutative tangent spaces as particular projective modules. These modules carry an induced connection from Euclidean space, and we compute its scalar curvature.
Translated tori in the characteristic varieties of complex hyperplane arrangements
Suciu, Alexander I.
1999-01-01
We give examples of complex hyperplane arrangements for which the top characteristic variety contains positive-dimensional irreducible components that do not pass through the origin of the character torus. These examples answer several questions of Libgober and Yuzvinsky. As an application, we exhibit a pair of arrangements for which the resonance varieties of the Orlik-Solomon algebra are (abstractly) isomorphic, yet whose characteristic varieties are not isomorphic. The difference comes fro...
Starbursts and dusty tori in distant 3CR radio galaxies
Podigachoski, P; Barthel, P D; Drouart, G; Fioc, M
2016-01-01
We present a study of the complete ultraviolet to submillimetre spectral energy distributions (SEDs) of twelve 3CR radio galaxy hosts in the redshift range $1.0 < z < 2.5$, which were all detected in the far-infrared by the Herschel Space Observatory. The study employs the new spectro-chemical evolutionary code P\\'EGASE.3, in combination with recently published clumpy AGN torus models. We uncover the properties of the massive host galaxy stellar populations, the AGN torus luminosities, and the properties of the recent starbursts, which had earlier been inferred in these objects from their infrared SEDs. The P\\'EGASE.3 fitting yields very luminous (up to 10$^{13}$L$_{\\odot}$) young stellar populations with ages of several hundred million years in hosts with masses exceeding 10$^{11}$M$_{\\odot}$. Dust masses are seen to increase with redshift, and a surprising correlation -- or better upper envelope behaviour -- is found between the AGN torus luminosity and the starburst luminosity, as revealed by their a...
Effect of alpha particles on the stability of Elmo Bumpy Torus (EBT) reactor. Final report
The macroscopic stability of an ignited EBT reactor is investigated by studying the effects of the alpha particles generated by the Deuterium-Tritium (D-T) fusion reaction on the background interchange mode, the interacting interchange mode, and the high-frequency compressional Alfven and coupled modes. A fluid description is used for the background plasma while a kinetic treatment is utilized for the hot electron species and the alpha particles. It is shown that the alphas tend to mildly destabilize the interacting interchange while stabilizing the background interchange due to their sizable Larmor radii. The destabilization is most pronounced when the beta of the alpha particles in highest, i.e., at birth, and recovery of stabilization takes place as these particles slow down toward thermalization. It is also shown that the alphas completely stabilize the high frequency modes so that it can safely be concluded that fusion alphas present no detrimental effects on the stability of an EBT reactor that possesses an appropriate hot electron ring for macroscopic stability
Damoiseaux, Jan; von Mühlen, Carlos A; Garcia-De La Torre, Ignacio; Carballo, Orlando Gabriel; de Melo Cruvinel, Wilson; Francescantonio, Paulo Luiz Carvalho; Fritzler, Marvin J; Herold, Manfred; Mimori, Tsuneyo; Satoh, Minoru; Andrade, Luis E C; Chan, Edward K L; Conrad, Karsten
2016-12-01
The International Consensus on ANA Patterns (ICAP) was initiated as a workshop aiming to thoroughly discuss and achieve consensus regarding the morphological patterns observed in the indirect immunofluorescence assay on HEp-2 cells. One of the topics discussed at the second ICAP workshop, and addressed in this paper, was the harmonization of reporting ANA test results. This discussion centered on the issue if cytoplasmic and mitotic patterns should be reported as positive or negative. This report outlines the issues that impact on two major different reporting methods. Although it was appreciated by all participants that cytoplasmic and mitotic patterns are clinically relevant, implications for existing diagnostic/classification criteria for ANA-associated diseases in particular hampered a final consensus on this topic. Evidently, a more concerted action of all relevant stakeholders is required. Future ICAP workshops may help to facilitate this action. PMID:26831867
The bumpy road Max Planck from radiation theory to the quantum (1896-1906)
Badino, Massimiliano
2015-01-01
This book examines the different areas of knowledge, traditions, and conceptual resources that contributed to the building of Max Planck’s theory of radiation. It presents an insightful comparative analysis that not only sheds light upon a fundamental chapter in the history of modern physics, but also enlarges our understanding of how theoreticians work. Coverage offers a deep investigation into the technical aspects behind the theory and extends in time the notion of quantum revolution. It also presents a full-fledged discussion of the combinatorial part of Planck’s theory and places emphasis on the epistemological role of mathematical practices. By painstakingly reconstructing both the electromagnetic and the combinatorial part of Planck’s black-body theory, the author shows how some apparently merely technical resources, such as the Fourier series, effectively contributed to shape the final form of Planck’s theory. For decades, historians have debated the conditions of possibility of Max Planck’s...
Quality-assurance approach for the Elmo Bumpy Torus Proof-of-Principal experiment
Components, subsystems and systems will be subjected to inspection and test as necessary to ensure compliance to applicable specifications, Acceptance Test Procedures and/or customer requirements. Quality Assurance will inspect each component, subsystem and system for selected mechanical and electrical defects. In addition, Quality Assurance will either perform, or verify performance of, and analyze, or verify analysis of, all required field and laboratory tests. If hardware is modified, repaired or replaced after final testing, necessary re-inspection and retest must be performed. Insofar as possible the component, subsystem or system will be released as acceptable upon completion of these activities. When nonconformances are detected during the course of site surveillance activities, MDAC or Gilbert/Commonwealth will initiate a Nonconformance Record for review by MDAC Quality Assurance and Project Engineering personnel. These nonconformances will be identified and dispositioned per MDAC Standard Practices with the advice and concurrence of Gilbert/Commonwealth personnel, if deemed appropriate. MDAC Quality Assurance personnel will witness the pre-operational testing and review the test data
A bumpy road to the top: Statistically defining a peak in oil production
Twenty-four countries where oil production is in decline were identified. A simple metric of the volatility of oil production on the upslope of their production curves, called decline as a proportion of pre-peak production (or PPPmax), was created. PPPmax was determined for the post-peak countries and plotted as a frequency distribution. PPPmax varied from 0–56%, but was skewed toward the lower part of the range (median 6.2%). As global production is determined by the total contribution of production from all countries, the variation in PPPmax will represent the lower and upper bound of the “bumpiness” of global oil production. It also enables a retrospective approximation of the when global oil production is most likely past its peak. -- Highlights: •Oil production is volatile which makes it difficult to determine peak production. •A measure of volatility based on oil production figures is described (PPPmax). •A frequency distribution of PPPmax gives insight into national production profiles. •PPPmax elucidates global production
Five years on the bumpy road delivering well chemicals for zero harmful discharge
Selle, Olav M.; Paltiel, Sten; Saeten, Jens O.; Nasvik, Haavard
2006-03-15
This is a summary of five years development work to qualify environmentally acceptable well chemicals for Heidrun. We will describe the situation as we started the work, what strategy we followed and the ups and downs we experienced as we went along. The focus is on scale inhibitors, scale dissolvers, acid formulations, viscosified fluids and chemicals for zonal isolation/shut-off purposes. The challenge has been to develop biodegradable and low toxic chemicals with equal or better effectiveness and with a reasonable prize compare to {sup b}est in class{sup -}products. The impact this has provided for zero harmful discharge to sea at Haltenbanken will be presented, to show the status as we are entering into year 2005. (Author)
M R Sreenivasa Murthy
2013-12-01
Full Text Available Genomics, a new bough of biotechnology responsible for gene mapping has acquired a rapid significance in the field of patents. Brisk growth of patent filing in genomic subject matter is raising serious concerns about their utility from the perspective of societal benefit. Though the genomic related patent application qualifies the criterion of invention and non-obviousness in major instances, the inventors are unable to satisfy the utility criterion. Some instances such as patent application for ESTs have no utility at all. The patent regulators constructed various tests to deal with the situation such as specificity, substantiality (real world credibility tests etc. Hoverer, it is noteworthy that an attempt to uniform the standard of utility test for genomic inventions especially in the field of ESTs, cloning and creation of chimeras, has been made by America and Europe through specific regulations. Thus, the objective of this paper is firstly, to explain the importance of biotechnology and genomic inventions for mankind and significance of ESTs for future research. Secondly, to analyze the application of Utility code prior to the emergence of Utility code in America and Europe. Thirdly to scrutinize the Utility code in both countries and their implication on aftermath cases, and. fourthly and finally, to critically evaluate the both countries utility pathways in the light of societal benefit.
Ion tails and lower-hybrid-drift turbulence in the ELMO Bumpy Torus
It is demonstrated that a low level of lower-hybrid-drift waves could explain the hot-ion tails observed in EBT; the tail temperature is related to the lower-hybrid-drift wave energy. The effect of these waves on the bulk ion distribution is also analyzed
The bumpy road toward low-energy urban mobility: Case studies from two UK cities
Tim Schwanen
2015-01-01
Cities are increasingly seen as the places where innovations that can trigger a sociotechnical transition toward urban mobility are emerging and maturing. Processes such as peak car, rail renaissance and cycling boom manifest themselves particularly in cities, and success stories of cities experimenting with specific types of low-energy mobility abound in the academic literature. Nonetheless, innovation is known to be a precarious process requiring favorable circumstances. Using document anal...
Bap re Bap! Driving Experiences through Multimodal Unruly Traffic on Bumpy Roads
N. AHMED; Iftekhar, L; Ahmed, S.; Rahman, R; Reza, T; Shoilee, S; Choudhury, CF
2015-01-01
Congestion, lack of compliance to traffic laws, multimodal traffic, opportunistic decision making and poor road conditions are few of the key challenges faced by drivers in a developing country's metropolitan city such as, Dhaka, Bangladesh. The driver's experience is affected by such road conditions which in turn shapes up their driving behavior and thus affects the traffic conditions which has been studied using sensor enabled tools as well as qualitative methods from a developing country's...
Elmo Bumpy Torus proof of principle. Phase II - title 1 report. Volume I. Device summary
This document presents a summary of the EBT-P Preliminary Design (Title I) effort. The work was performed, under the direction of ORNL, for the Department of Energy by MDAC-St. Louis. Major subcontractors assisting MDAC included General Dynamics for the magnet system, Gilbert Associates for the device utilities and facility architecture and engineering, and Lockheed - Oak Ridge for engineering support services. The Title I period of performance was from 1 October 1980 to 1 March 1982
Actually the World Is Quite Bumpy: Using Friedman in the International Business Law Classroom
Dhooge, Lucien J.
2006-01-01
In "The World Is Flat: A Brief History of the Twenty-First Century," Pulitzer Prize recipient and New York Times foreign affairs correspondent Thomas L. Friedman examines the evolution of globalization in the six years since the publication of his highly acclaimed introduction to the topic in "The Lexus and the Olive Tree: Understanding…
Elmo Bumpy Torus proof of principle, Phase II: Title 1 report. Volume II. Toroidal vessel
The Toroidal Vessel provides the vacuum enclosure for containing the high temperature steady state plasma. In addition, the Toroidal Vessel must provide several viewing ports for plasma diagnostics, vacuum pumping ports for both high vacuum and roughing vacuum, feed-through ports for ECRH waveguides, limiter feed throughs for cooling and supporting the limiters, and ports for ion gages. The vessel must operate in an intense environment comprised of x-rays, microwaves, magnetic fields and plasma heat loads as well as the atmosphere pressure and gravity loads and the internal thermal stress loads due to heating and cooling of the torus. A key issue addressed was the choice of vacuum vessel seal and wall materials. In addition, during the course of the study, ORNL requested that horsecollar diagnostic ports be incorporated in the design. A comprehensive trade study was performed considering the vessel material issues in concert with the impact of the horsecollar port design. A change in baseline from an aluminum vessel with elastomer seals and circular diagnostic ports to austenitic stainless steel vessel with metal seals and horsecollar ports was agreed upon by both MDAC and ORNL towards the end of Title I
Dvandvas, Blocking, and the Associative: The Bumpy Ride from Phrase to Word
Kiparsky, Paul
2010-01-01
The oldest form of Sanskrit has a class of expressions that are in some respects like asyndetically coordinated syntactic phrases, in other respects like single compound words. I propose to resolve the conflicting evidence by drawing on prosodic phonology, stratal optimality theory, and the lexicalist approach to morphological blocking. I then…
Elmo Bumpy Torus physics. Interim technical report, May 24, 1983-October 1, 1983
This progress report covers the technical work performed during the initial funding period of the contract, May 24-October 1, 1983. The contract presently includes work on three tasks: T-M Transition studies on EBT-S, pulsed high density experiments on EBT-S, and theoretical studies of ion rings in EBT. The work on Task 2 consisted of developing a preliminary plan for the pulsed experiments and some exploratory experimental runs on EBT-S. Within the Task 3 effort considerable work was accomplished on ion ring formation. This work was able to benefit from previous research and code development done at MDAC. This report also covers preliminary results on investigation of stabilization of ballooning and interchange modes by high energy rings. This investigation is particularly important for ion rings because, should stabilization properties depend on ion energy in the rings, the required ion energies could be important in power balance considerations
Bumpy Spin-Down of Anomalous X-Ray Pulsars The Link with Magnetars
Melatos, A
1999-01-01
The two anomalous X-ray pulsars (AXPs) with well-sampled timing histories, 1E 1048.1-5937 and 1E 2259+586, are known to spin down irregularly, with `bumps' superimposed on an overall linear trend. Here we show that if AXPs are non-accreting magnetars, i.e. isolated neutron stars with surface magnetic fields B_0 > 10^{10} T, then they spin down electromagnetically in exactly the manner observed, due to an effect called `radiative precession'. Internal hydromagnetic stresses deform the star, creating a fractional difference epsilon=(I_3-I_1)/I_1 ~ 10^{-8} between the principal moments of inertia I_1 and I_3; the resulting Eulerian precession couples to an oscillating component of the electromagnetic torque associated with the near-zone radiation fields, and the star executes an anharmonic wobble with period tau_pr ~ 2 pi / epsilon Omega(t) ~ 10 yr, where Omega(t) is the rotation frequency as a function of time t. We solve Euler's equations for a biaxial magnet rotating in vacuo; show that the computed Omega(t) ...
The Bumpy Road toward Low-Energy Urban Mobility: Case Studies from Two UK Cities
Tim Schwanen
2015-06-01
Full Text Available Cities are increasingly seen as the places where innovations that can trigger a sociotechnical transition toward urban mobility are emerging and maturing. Processes such as peak car, rail renaissance and cycling boom manifest themselves particularly in cities, and success stories of cities experimenting with specific types of low-energy mobility abound in the academic literature. Nonetheless, innovation is known to be a precarious process requiring favorable circumstances. Using document analysis and in-depth interviews, this study examines the nature of low-energy innovation in the everyday mobility of people in two UK cities with favorable conditions for a transition away from fossil fuels—Brighton and Oxford. It shows that clear differences exist between the two cities in the sorts of innovation that emerge and diffuse as a result of path dependencies, local politics, and financial support from supra-local governments and agencies. While low-energy mobility currently has substantial momentum in both cities, the majority of low-carbon innovations in urban mobility are incremental rather than radical in nature, and their future is often imbued with uncertainty. The autonomy of small- and medium-sized cities as agents in bringing about transformational change toward low-energy urban mobility should not be overestimated.
Elmo Bumpy Torus proof of principle, Phase II: Title 1 report. Volume VIII. Device utilities
This report describes the activities conducted during the Preliminary Design Period for the Device Utilities Systems. All GAI preliminary specifications, drawings, and reports (listed in Section 4.0) have been transmitted to ORNL for review and approval. Device Utility Systems Descriptions are also presented in Section 4.0. The GAI Device Enclosure Gamma Radiation Analysis is presented in Appendix B. Pending design criteria revisions are described in Section 6.0. A type B Change Notice Request (CNR) has been transmitted to GAI. The Type B CNR authorizes cost and schedule assessment for each revision identified. Formal Proposed Design Changes (PDC's) will be provided to ORNL when this data is available
Fusion energy division annual progress report, period ending December 31, 1980
1981-11-01
The ORNL Program encompasses most aspects of magnetic fusion research including research on two magnetic confinement programs (tokamaks and ELMO bumpy tori); the development of the essential technologies for plasma heating, fueling, superconducting magnets, and materials; the development of diagnostics; the development of atomic physics and radiation effect data bases; the assessment of the environmental impact of magnetic fusion; the physics and engineering of present-generation devices; and the design of future devices. The integration of all of these activities into one program is a major factor in the success of each activity. An excellent example of this integration is the extremely successful application of neutral injection heating systems developed at ORNL to tokamaks both in the Fusion Energy Division and at Princeton Plasma Physics Laboratory (PPPL). The goal of the ORNL Fusion Program is to maintain this balance between plasma confinement, technology, and engineering activities.
Fusion energy division annual progress report, period ending December 31, 1980
The ORNL Program encompasses most aspects of magnetic fusion research including research on two magnetic confinement programs (tokamaks and ELMO bumpy tori); the development of the essential technologies for plasma heating, fueling, superconducting magnets, and materials; the development of diagnostics; the development of atomic physics and radiation effect data bases; the assessment of the environmental impact of magnetic fusion; the physics and engineering of present-generation devices; and the design of future devices. The integration of all of these activities into one program is a major factor in the success of each activity. An excellent example of this integration is the extremely successful application of neutral injection heating systems developed at ORNL to tokamaks both in the Fusion Energy Division and at Princeton Plasma Physics Laboratory (PPPL). The goal of the ORNL Fusion Program is to maintain this balance between plasma confinement, technology, and engineering activities
This report summarizes Title I Preliminary Design of the EBT-P Vacuum Pumping System. The Vacuum Pumping System has been designed by the McDonnell Douglas Astronautics Co. - St. Louis (MDAC). It includes the necessary vacuum pumps and vacuum valves to evacuate the torus, the Mirror Coil Dewars (MC Dewars), and the Gyrotron Magnet Dewars. The pumping ducts, manifolds, and microwave protection system are also included. A summary of the function of each subsystem and a description of its principle components is provided below. The analyses performed during the system design are also identified
Four Goals of School Reform in the Soviet Union, 1984-1989: A Bumpy Journey for "Perestroika".
Wilson, Joan B.
Examined is the progress of four major goals of school reform in the Soviet Union as an integral part of Soviet leader Mikhail S. Gorbachev's call for a monumental restructuring (perestroika) of society. With the adoption of Fundamental Directions of General Education and Vocational School Reform (1984), four important goals were set in motion;…
None
1980-09-09
This report provies background information and rationale for the procedures used and decisions made up to this point. A brief history and technical description of the EBT concept are given. The OFE recommendations as to siting are included. (MOW)
Kim Vancampenhout
Full Text Available The advent of massive parallel sequencing (MPS has revolutionized the field of human molecular genetics, including the diagnostic study of mitochondrial (mt DNA dysfunction. The analysis of the complete mitochondrial genome using MPS platforms is now common and will soon outrun conventional sequencing. However, the development of a robust and reliable protocol is rather challenging. A previous pilot study for the re-sequencing of human mtDNA revealed an uneven coverage, affecting predominantly part of the plus strand. In an attempt to address this problem, we undertook a comparative study of standard and modified protocols for the Ion Torrent PGM system. We could not improve strand representation by altering the recommended shearing methodology of the standard workflow or omitting the DNA polymerase amplification step from the library construction process. However, we were able to associate coverage bias of the plus strand with a specific sequence motif. Additionally, we compared coverage and variant calling across technologies. The same samples were also sequenced on a MiSeq device which showed that coverage and heteroplasmic variant calling were much improved.
This report provies background information and rationale for the procedures used and decisions made up to this point. A brief history and technical description of the EBT concept are given. The OFE recommendations as to siting are included
During Title I, General Dynamics' principal role as a subcontractor to the McDonnell Douglas Astronautics Company (MDAC) is to assist in the further development of a low-cost superconducting magnet mirror coil system for the EBT-P program consistent with long life and dependable operation. The activity can best be defined as an extension of ORNL's previous development program with further joint ORNL/MDAC/GDC refining of the mirror coil components. MDAC/GDC participation for the entire program can be subdivided into four distinct elements as follows: (1) design, development, and fabrication of two dewar subassemblies to enclose the ORNL developed and fabricated cold mass assemblies; (2) design, development, and fabrication of a production prototype magnet system including conductor (procurement), cold mass components, dewar and x-ray shield. This prototype would form the basis for the production of 36 magnets for the torus and three spares. (3) design, development, and fabrication of an electrical/electronic system including quench protection, instrumentation and control, and power supply to power and protect the mirror coil system during its operation in the torus; (4) fabrication of the 39 production magnets
The EBT-P Microwave System provides microwaves for electron cyclotron resonance heating (ECRH) to both stabilize and heat the EBT-P plasma. A 28 gigahertz (GHz) system is required to form the hot electron annulus plasma that provides MHD stabilization to the core plasma. A 60 GHz system is required to heat the core plasma and will provide some second harmonic heating of the hot electron annulus. The principal microwave system elements and their design characteristics are summarized. The microwave system includes 200 kilowatt (kW) gyrotrons at 60 GHz for core heating and 200 kW gyrotrons at 28 GHz for annulus heating. The basic operating complement will be six (6) 60 GHz tubes and two (2) 28 GHz tubes. PACE (Plant and Capital Equipment) procurement will include four (4) 60 GHz gyrotrons with two (2) GHz tubes procured under operations and the two (2) 28 GHz tubes will be provided, with mounts, from the EBT-S program. Each tube is rigidly mounted on an oil filled tank assembly which provides electrical isolation and cooling. All tubes and mounts will be located in the lower level of the torus enclosure. An extensive demineralized water flow system is required to provide gyrotron cooling
Kent C. Condie
2013-05-01
Full Text Available Zircon age peaks at 2100–1650 and 1200–1000 Ma correlate with craton collisions in the growth of supercontinents Nuna and Rodinia, respectively, with a time interval between collisions mostly <50 Myr (range 0–250 Myr. Collisional orogens are two types: those with subduction durations <500 Myr and those ≥500 Myr. The latter group comprises orogens with long-lived accretionary stages between Nuna and Rodinia assemblies. Neither orogen age nor duration of either subduction or collision correlates with the volume of orogen preserved. Most rocks preserved date to the pre-collisional, subduction (ocean-basin closing stage and not to the collisional stage. The most widely preserved tectonic setting in Proterozoic orogens is the continental arc (10%–90%, mean 60%, with oceanic tectonic settings (oceanic crust, arcs, islands and plateaus, serpentinites, pelagic sediments comprising <20% and mostly <10%. Reworked components comprise 20%–80% (mean 32% and microcratons comprise a minor but poorly known fraction. Nd and Hf isotopic data indicate that Proterozoic orogens contain from 10% to 60% of juvenile crust (mean 36% and 40%–75% reworked crust (mean 64%. Neither the fraction nor the rate of preservation of juvenile crust is related to the collision age nor to the duration of subduction. Regardless of the duration of subduction, the amount of juvenile crust preserved reaches a maximum of about 60%, and 37% of the volume of juvenile continental crust preserved between 2000 and 1000 Ma was produced in the Great Proterozoic Accretionary Orogen (GPAO. Pronounced minima occur in frequency of zircon ages of rocks preserved in the GPAO; with minima at 1600–1500 Ma in Laurentia; 1700–1600 Ma in Amazonia; and 1750–1700 Ma in Baltica. If these minima are due to subduction erosion and delamination as in the Andes in the last 250 Myr; approximately one third of the volume of the Laurentian part of the GPAO could have been recycled into the mantle between 1500 and 1250 Ma. This may have enriched the mantle wedge in incompatible elements and water leading to the production of felsic magmas responsible for the widespread granite-rhyolite province of this age. A rapid decrease in global Nd and in detrital zircon Hf model ages between about 1600 and 1250 Ma could reflect an increase in recycling rate of juvenile crust into the mantle; possibly in response to partial fragmentation of Nuna.
We explore the effects of long-term secular perturbations on the distribution of dark matter particles around supermassive black hole (BH) binaries. We show that in the hierarchical (in separation) three-body problem, one of the BHs and a dark matter particle form an inner binary. Gravitational perturbations from the BH companion, on a much wider orbit, can cause the dark matter particle to reach extremely high eccentricities and even get accreted onto the BH by what is known as the eccentric Kozai-Lidov (EKL) mechanism. We show that this may produce a torus-like configuration for the dark matter distribution around the less massive member of the BH binary. We first consider an intermediate BH (IMBH) in the vicinity of our galactic center, which may be a relic of a past minor merger. We show that if the IMBH is close enough (i.e., near the stellar disk) the EKL mechanism is very efficient in exciting the eccentricity of dark matter particles in near-polar configurations to extremely high values where they are accreted by the IMBH. We show that this mechanism is even more effective if the central BH grows in mass, where we have assumed adiabatic growth. Because near-polar configurations are disrupted, a torus-like shape is formed. We also show that this behavior is also likely to be relevant for supermassive BH binaries. We suggest that if the BHs are spinning, the accreted dark matter particles may linger in the ergosphere, and thereby generate self-annihilations and produce an indirect signature of potential interest.
THE UTILIZATION OF THE THERAPEUTIC TOY IN THE NURSING OPERA TORY VISIT TO THE INFANT
Cláudia Silveira Viera
2003-12-01
Full Text Available The systematization of the peroperative nursing occurs in the moments pre, trans and postoperativeand also they happen in children, adolescents, adults and elders. Being like this, ours objective went verify thebenefits of the utilization of the therapeutic toy in the visit preoperative by the nurse of surgical center.
Akumulátory energie pro blízkou budoucnost
Zajac, Jaromír
-, č. 5 (2006), s. 14-15 Institutional research plan: CEZ:AV0Z20430508 Keywords : tokamak * power sources * energy accumulation Subject RIV: JE - Non-nuclear Energetics, Energy Consumption ; Use http://www.tretipol.cz/
THE UTILIZATION OF THE THERAPEUTIC TOY IN THE NURSING OPERA TORY VISIT TO THE INFANT
Cláudia Silveira Viera; Marister Piccoli; Silvana Machiavelli Schmitz
2003-01-01
The systematization of the peroperative nursing occurs in the moments pre, trans and postoperativeand also they happen in children, adolescents, adults and elders. Being like this, ours objective went verify thebenefits of the utilization of the therapeutic toy in the visit preoperative by the nurse of surgical center.
Vanadové články jako zdroje a akumulátory energie
Langr, Pavel
2015-01-01
Tato semestrální práce se zabývá problematikou průtokových redoxních baterií, zejména pak vanadových článků. První část se soustředí na vysvětlění základních pojmů, popisuje vanadové redoxní baterie a vysvětluje chemické procesy v nich. Zabývá se též jejich vlastnostmi a konstrukcí. Druhá část popisuje diagnostickou metodu spektroskopie, která se jeví jako velice perspektivní právě pro zkoumání vlastností vanadových článků. This semestral thesis deals with problematics of redox flow batter...
Naoz, Smadar [Harvard Smithsonian Center for Astrophysics, Institute for Theory and Computation, 60 Garden St., Cambridge, MA 02138 (United States); Silk, Joseph, E-mail: snaoz@astro.ucla.edu [Institut d' Astrophysique de Paris, CNRS, UPMC Univ Paris 06, UMR7095, 98 bis, boulevard Arago, F-75014, Paris (France)
2014-11-10
We explore the effects of long-term secular perturbations on the distribution of dark matter particles around supermassive black hole (BH) binaries. We show that in the hierarchical (in separation) three-body problem, one of the BHs and a dark matter particle form an inner binary. Gravitational perturbations from the BH companion, on a much wider orbit, can cause the dark matter particle to reach extremely high eccentricities and even get accreted onto the BH by what is known as the eccentric Kozai-Lidov (EKL) mechanism. We show that this may produce a torus-like configuration for the dark matter distribution around the less massive member of the BH binary. We first consider an intermediate BH (IMBH) in the vicinity of our galactic center, which may be a relic of a past minor merger. We show that if the IMBH is close enough (i.e., near the stellar disk) the EKL mechanism is very efficient in exciting the eccentricity of dark matter particles in near-polar configurations to extremely high values where they are accreted by the IMBH. We show that this mechanism is even more effective if the central BH grows in mass, where we have assumed adiabatic growth. Because near-polar configurations are disrupted, a torus-like shape is formed. We also show that this behavior is also likely to be relevant for supermassive BH binaries. We suggest that if the BHs are spinning, the accreted dark matter particles may linger in the ergosphere, and thereby generate self-annihilations and produce an indirect signature of potential interest.
Parogenerátory tlakovodních reaktorů
Michalica, Martin
2015-01-01
Tato bakalářská práce se zabývá popisem jednotlivých konstrukčních řešení parogenerátorů. V první části bakalářské práce je popsán počátek jaderného průmyslu v Rusku. Samostatná práce se věnuje jednotlivým konstrukčním řešením. Poslední kapitola detailně popisuje jednotlivé části parogenerátoru VVER 1000. Součástí práce je tvorba 3D modelu parogenerátoru VVER 1000, který bude sloužit jako učební pomůcka v projektu Cenelín. This bachelors thesis describes various designs of steam generators...
Linn andis loa Osten Tori juurde kõrgete korrusmajade ehitamiseks / Askur Alas
Alas, Askur, 1973-
2004-01-01
Tallinna linnavalitsus kehtestas Pärnu maantee ja Alevi tänava nurga detailplaneeringu, mille kohaselt kerkivad sinna üks 9- ja üks 12-korruseline äri- ja kortermaja. Projekti koostas Tõnu Laigu OÜ-st QP Arhitektid
Mid-infrared interferometry of 23 AGN tori: On the significance of polar-elongated emission
López-Gonzaga, N; Tristram, K R W; Meisenheimer, K; Schartmann, M
2016-01-01
Context. Detailed high resolution studies of AGN with mid-infrared (MIR) interferometry have revealed parsec-sized dust emission elongated in the polar direction in four sources. Aims. Using a larger, coherently analyzed sample of AGN observed with MIR interferometry, we aim to identify elongated mid-infrared emission in a statistical sample of sources. More specifically we wish to determine if there is indeed a preferred direction of the elongation and whether this direction is consistent with a torus-like structure or with a polar emission. Methods. We investigate the significance of the detection of an elongated shape in the MIR emission by fitting elongated Gaussian models to the interferometric data at 12 um. We pay special attention to 1) the uncertainties caused by an inhomogeneous (u,v) coverage, 2) the typical errors in the measurements and 3) the spatial resolution achieved for each object. Results. From our sample of 23 sources we are able to find elongated parsec-scale MIR emission in five sources...
Role of electric charge in shaping equilibrium configurations of fluid tori encircling black holes
Kovář, J.; Slaný, P.; Stuchlík, Z.; Karas, Vladimír; Cremaschini, C.; Miller, J. C.
2011-01-01
Roč. 84, č. 8 (2011), 084002/1-084002/14. ISSN 1550-7998 R&D Projects: GA MŠk(CZ) LC06014; GA ČR GA205/07/0052 Institutional research plan: CEZ:AV0Z10030501 Keywords : black holes Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.558, year: 2011
Delayed outflows from black hole accretion tori following neutron star binary coalescence
Fernández, Rodrigo
2013-01-01
Expulsion of neutron-rich matter following the merger of neutron star (NS) binaries is crucial to the radioactively-powered electromagnetic counterparts of these events and to their relevance as sources of r-process nucleosynthesis. Numerical simulations of NS-NS coalescence find, however, a wide range in the quantity of prompt dynamically-ejected mass. Here we explore the long-term (viscous) evolution of remnant black hole accretion disks formed in such mergers by means of two-dimensional, time-dependent hydrodynamical simulations. The evolution of the electron fraction due to charged-current weak interactions is included, and neutrino self-irradiation is modeled as a lightbulb that accounts for the disk geometry and moderate optical depth effects. Over several viscous times (~1s), a fraction ~10% of the initial disk mass is ejected as a moderately neutron-rich wind (Y_e ~ 0.2) powered by viscous heating and nuclear recombination, with neutrino self-irradiation playing a sub-dominant role. Although the prope...
Studies of spherical tori, stellarators and anisotropic pressure with the M3D code
The Multi-level 3D (M3D) project simulates plasmas using multiple levels of physics, geometry and grid models in one code package. The M3D code has been extended to fundamentally non-axisymmetric and small aspect ratio, R/a > or ∼ 1, configurations. Applications include the non-linear stability of the NSTX spherical torus and of the spherical pinch, as well as the relaxation of stellarator equilibria. The fluid level physics model has been extended to evolve the anisotropic pressures pjparallel and pjperpendicular for the ion and electron species and has been applied to magnetic island evolution. (author)
Mid-infrared interferometry of 23 AGN tori: On the significance of polar-elongated emission
López-Gonzaga, N.; Burtscher, L.; Tristram, K. R. W.; Meisenheimer, K.; Schartmann, M.
2016-06-01
Context. Detailed high-resolution studies of active galactic nuclei (AGN) with mid-infrared (MIR) interferometry have revealed parsec-sized dust emission that is elongated in the polar direction in four sources. Aims: Using a larger, coherently analyzed sample of AGN observed with MIR interferometry, we aim to identify elongated MIR emission in a statistical sample of sources. More specifically, we wish to determine if there is indeed a preferred direction of the elongation and whether this direction is consistent with a torus-like structure or with a polar emission. Methods: We investigated the significance of the detection of an elongated shape in the MIR emission by fitting elongated Gaussian models to the interferometric data at 12 μm. We paid special attention to (1) the uncertainties caused by an inhomogeneous (u,v) coverage; (2) the typical errors in the measurements; and (3) the spatial resolution achieved for each object. Results: From our sample of 23 sources, we are able to find elongated parsec-scale, MIR emission in five sources: three type 2s, one type 1i, and one type 1. Elongated emission in four of these sources has been published before; NGC 5506 is a new detection. The observed axis ratios are typically around 2 and the position angle of the 12 μm emission for all the elongated sources always seems to be closer to the polar axis of the system than to the equatorial axis. Two other objects, NGC 4507 and MCG-5-23-16, with reasonably well-mapped (u,v) coverage and good signal-to-noise ratios, appear to have a less elongated 12 μm emission. Conclusions: Our finding that sources showing elongated MIR emission are preferentially extended in polar direction sets strong constraints on torus models or implies that both the torus and NLR/outflow region have to be modeled together. In addition, models used for SED fitting will have to be revised to include emission from polar dust.
(Re)presenting Equestrian "His"tories--Storytelling as a Method of Inquiry
Linghede, Eva; Larsson, Håkan; Redelius, Karin
2016-01-01
Responding to calls about the need to "give voice" to groups previously marginalized in research and to challenge meta-narratives about men in sports, this paper explores the use of a narrative approach to illuminate men's experiences--and the doing of gender--within equestrian sports, a sport dominated by women in Sweden. Adopting the…
Analyzátory výfukových emisí vozidel
Přeučil, Martin
2013-01-01
The aim of this work is to describe the development and current knowledge in the design of the exhaust emissions of internal combustion analyzers motorů.Bakalářská work includes analysis of emissions from internal combustion engines, their composition and the description of the individual components. Besides, the description of the technical equipment for analysis of exhaust emissions of internal combustion engines and the principles on which these devices operate. The next chapter covers the...
A Female Interrogative Reader: The Adolescent Jane Austen Reads and Rewrites (His)tory.
Reid-Walsh, Jacqueline
1992-01-01
Argues that Jane Austen's unpublished juvenile work "The History of England" has considerable relevance to twentieth-century high-school English classrooms. Notes that the work humorously shows the gender bias of traditional history texts because it is a "woman-centered" rewriting. (RS)
Bifurcations of cycles and tori in one boundary value problem for the nonlocal equation of erosion
A partial differential equation with deviating spatial variables has been considered. The case of small deviations has been studied. It has been shown that spatially inhomogeneous solutions can be sought as bifurcating solutions from homogeneous equilibrium states and that the wavelength of the corresponding solutions depends almost only on one parameter, the magnitude of deviation
Quasi-localized wavefunctions on magnetized tori and tiny neutrino Yukawa couplings
Sumita, Keigo
2016-01-01
This paper shows that, a quasi-localization of wavefunctions in toroidal compactifications with magnetic fluxes can lead to a strong suppression for relevant Yukawa couplings, and it is applicable to obtain tiny neutrino masses. Although it is known that magnetic fluxes lead to a Gaussian profile of zero-modes on a torus and that can yield a suppressed coupling in higher-dimensional supersymmetric Yang-Mills (SYM) theories, the largest (diagonal) entry of Yukawa matrices is always of O(1) . In this paper, we propose a way to induce an absolutely tiny global factor of Yukawa matrices. In two SYM theories defined in different dimensional spacetime, their bifundamental representations must be localized as a point in some directions. Overlaps of such point-like localized wavefunctions and Gaussian zero-modes give a global factor of Yukawa matrices, and it can be a strong suppression factor or a usual O(1) factor, corresponding to their distance. Our numerical analysis shows that it is possible to obtain a suppression strong enough to realize the tiny neutrino masses without a fine-tuning. Furthermore, we propose a concrete model in a magnetized SYM system and demonstrate the mechanism to generate the tiny neutrino Yukawa couplings.
Quasi-localized wavefunctions on magnetized tori and tiny neutrino Yukawa couplings
Sumita, Keigo
2015-01-01
This paper shows that, a quasi-localization of wavefunctions in toroidal compactifications with magnetic fluxes can lead to a strong suppression for relevant Yukawa couplings, and it is applicable to obtain tiny neutrino masses. Although it is known that magnetic fluxes lead to a Gaussian profile of zero-modes on a torus and that can yield a suppressed coupling in higher-dimensional supersymmetric Yang-Mills (SYM) theories, the largest (diagonal) entry of Yukawa matrices is always of $\\mathcal O(1)$. In this paper, we propose a way to induce an absolutely tiny global factor of Yukawa matrices. In two SYM theories defined in different dimensional spacetime, their bifundamental representations must be localized as a point in some directions. Overlaps of such point-like localized wavefunctions and Gaussian zero-modes give a global factor of Yukawa matrices, and it can be a strong suppression factor or a usual $\\mathcal O(1)$ factor, corresponding to their distance. Our numerical analysis shows that it is possibl...
Effect of the toroidal magnetic field on the runaway instability of relativistic tori
Hamerský, Jaroslav; Karas, Vladimír
2013-01-01
Roč. 555, July (2013), A32/1-A32/8. ISSN 0004-6361 R&D Projects: GA ČR(CZ) GC13-00070J Institutional support: RVO:67985815 Keywords : accretion * accretion disks * black hole physics Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.479, year: 2013
Triggered oscillations and destruction of magnetized relativistic tori in 2D
Hamerský, Jaroslav; Karas, Vladimír
Opava: Silesian University, 2014 - (Stuchlík, Z.), s. 107-114. (Publications of the Institute of Physics. 7). ISBN 9788075101266. ISSN 2336-5668. [RAGtime /14.-16./. Opava (CZ), 18.09.2012-22.09.2012] R&D Projects: GA ČR(CZ) GC13-00070J Institutional support: RVO:67985815 Keywords : accretion discs * black hole physics Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics
Cremaschini, C.; Kovář, J.; Slaný, P.; Stuchlík, Z.; Karas, Vladimír
2013-01-01
Roč. 209, č. 15 (2013), s. 1-12. ISSN 0067-0049 R&D Projects: GA ČR(CZ) GC13-00070J Institutional support: RVO:67985815 Keywords : accretion * gravitation * black holes Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 14.137, year: 2013
Integrated-blanket-coil (IBC) concept applied to the OH-coil for spherical tori
This concept combines blanket and coil functions into a single component. The objectives of the concept are to: (1) provide design options, (2) simplify overall configuration, (3) enhance compactness, and (4) reduce costs. Some drawings of the system are given
An X-ray spectral model for clumpy tori in active galactic nuclei
Liu, Yuan; Li, Xiaobo, E-mail: liuyuan@ihep.ac.cn, E-mail: lixb@ihep.ac.cn [Key Laboratory of Particle Astrophysics, Institute of High Energy Physics, Chinese Academy of Sciences, P.O. Box 918-3, Beijing 100049 (China)
2014-05-20
We construct an X-ray spectral model for the clumpy torus in an active galactic nucleus (AGN) using Geant4, which includes the physical processes of the photoelectric effect, Compton scattering, Rayleigh scattering, γ conversion, fluorescence line, and Auger process. Since the electrons in the torus are expected to be bounded instead of free, the deviation of the scattering cross section from the Klein-Nishina cross section has also been included, which changes the X-ray spectra by up to 25% below 10 keV. We have investigated the effect of the clumpiness parameters on the reflection spectra and the strength of the fluorescent line Fe Kα. The volume filling factor of the clouds in the clumpy torus only slightly influences the reflection spectra, however, the total column density and the number of clouds along the line of sight significantly change the shapes and amplitudes of the reflection spectra. The effect of column density is similar to the case of a smooth torus, while a small number of clouds along the line of sight will smooth out the anisotropy of the reflection spectra and the fluorescent line Fe Kα. The smoothing effect is mild in the low column density case (N {sub H} = 10{sup 23} cm{sup –2}), whereas it is much more evident in the high column density case (N {sub H} = 10{sup 25} cm{sup –2}). Our model provides a quantitative tool for the spectral analysis of the clumpy torus. We suggest that the joint fits of the broad band spectral energy distributions of AGNs (from X-ray to infrared) should better constrain the structure of the torus.
An X-ray spectral model for clumpy tori in active galactic nuclei
Liu, Yuan
2014-01-01
We construct an X-ray spectral model for the clumpy torus in an active galactic nucleus (AGN) using Geant4, which includes the physical processes of the photoelectric effect, Compton scattering, Rayleigh scattering, $\\gamma$ conversion, fluorescence line, and Auger process. Since the electrons in the torus are expected to be bounded instead of free, the deviation of the scattering cross section from the Klein-Nishina cross section has also been included, which changes the X-ray spectra by up to 25% below $10$ keV. We have investigated the effect of the clumpiness parameters on the reflection spectra and the strength of the fluorescent line Fe K$\\alpha$. The volume filling factor of the clouds in the clumpy torus only slightly influences the reflection spectra, however, the total column density and the number of clouds along the line of sight significantly change the shapes and amplitudes of the reflection spectra. The effect of column density is similar to the case of a smooth torus, while a small number of c...
Indikátory změn půdní biodiverzity
Rusek, Josef
první. Praha : Academia, 2005 - (Vačkář, D.), s. 249-261 ISBN 80-200-1386-5 Institutional research plan: CEZ:AV0Z60660521 Keywords : biodiversity of soil organisms * biodiversity monitoring in soils * monitoring network Subject RIV: EH - Ecology, Behaviour
Daniel Adam z Veleslavína a jeho nomenklátory
Černá, Alena M.
Praha: Karolinum, 2012 - (Čmejrková, S.; Hoffmannová, J.; Klímová, J.), s. 201-206 ISBN 978-80-246-2121-0. [Čeština v pohledu synchronním a diachronním. Praha (CZ), 01.06.2011-03.06.2011] R&D Projects: GA ČR GAP406/10/1140 Institutional research plan: CEZ:AV0Z90610518 Keywords : Humanistic Czech * Daniel Adam of Veleslavin * vocabulary Subject RIV: AI - Linguistics
The formulation of a general strategy for implementing semiclassical quantization using the adiabatic-switching method, presented in the preceding paper for two-dimensional systems, is generalized to multidimensional systems. The method is shown to produce accurate semiclassical eigenvalues for the realistic polynomial potential describing SO2 as well as for model potentials for other multidimensional systems. The results are compared with semiclassical results obtained with use of other methods
Saini, S.; Zakrzewski, J.; Taylor, H.S.
1988-10-15
The formulation of a general strategy for implementing semiclassical quantization using the adiabatic-switching method, presented in the preceding paper for two-dimensional systems, is generalized to multidimensional systems. The method is shown to produce accurate semiclassical eigenvalues for the realistic polynomial potential describing SO/sub 2/ as well as for model potentials for other multidimensional systems. The results are compared with semiclassical results obtained with use of other methods.
The Witten-Reshetikhin-Turaev invariants of finite order mapping tori I
Ellegaard Andersen, Jørgen
polynomial in the level $k$, weighted by a complex phase, which is $k$ times the Chern-Simons invariant corresponding to the component. We express the coefficients of these polynomials in terms of cohomological pairings on the fixed point set of the moduli space of flat connections on the surface. We...... explicitly describe the fixed point set in terms of moduli spaces of the quotient orbifold Riemann surface and for the smooth components we express the aforementioned coefficients in terms of the known generators of the cohomology ring. We provide an explicit formula in terms of the Seifert invariants of the...
String theory flux vacua on twisted tori and generalized complex geometry
This thesis is devoted to the study of flux vacua of string theory, with the ten-dimensional space-time split into a four-dimensional maximally symmetric space-time, and a six-dimensional internal manifold M, taken to be a solv-manifold (twisted torus). Such vacua are of particular interest when trying to relate string theory to supersymmetric (SUSY) extensions of the standard model of particles, or to cosmological models. For SUSY solutions of type II supergravities, allowing for fluxes on M helps to solve the moduli problem. Then, a broader class of manifolds than just the Calabi-Yau can be considered for M, and a general characterization is given in terms of Generalized Complex Geometry: M has to be a Generalized Calabi-Yau (GCY). A subclass of solv-manifolds have been proven to be GCY, so we look for solutions with such M. To do so, we use an algorithmic resolution method. Then we focus on specific new solutions: those admitting an intermediate SU(2) structure. A transformation named the twist is then discussed. It relates solutions on torus to solutions on solv-manifolds. Working out constraints on the twist to generate solutions, we can relate known solutions, and find a new one. We also use the twist to relate flux vacua of heterotic string. Finally we consider ten-dimensional de Sitter solutions. Looking for such solutions is difficult, because of several problems among which the breaking of SUSY. We propose an Ansatz for SUSY breaking sources which helps to overcome these difficulties. We give an explicit solution on a solv-manifold, and discuss partially its four-dimensional stability. (author)