Cassures double-brin de l'ADN, cassures chrosomiques et létalité des cellules humaines irradiées
Foray, N.; Arlett, C. F.; Malaise, E. P.
1998-04-01
DNA double-strand breaks (DSB) are the likely event which may explain the radiation-induced killing effect in mammalian cells. An overview of the litterature shows that, to the exception of a small group of human tumours, the repair defect rather than the induction rate of DSB plays the major role. However, the arguments supporting the relationship between DSB and intrinsic radiosensitivity are most often indirect. Our results dealing with intrinsic radiosensitivity, residual DNA DSB and chromosome breaks have been achieved with untransformed human fibroblasts (5 control and 18 hypersensitive cell lines). We describe a quantitative relationship between the intrinsic radiosensitivity and the residual breaks. The death of a human fibroblast is linked to 1.3 unrepaired chromosome break and 6.6 unrepaired DSB. Les cassures double-brin (CDB) de l'ADN constituent l'événement-clé susceptible d'expliquer l'effet létal des radiations ionisantes. Une revue générale de la littérature montre que, à l'exception d'un groupe minoritaire de tumeurs humaines, c'est surtout une déficience de réparation plutôt que l'incidence des dégâts qui est associée à la mort des cellules de mammifères irradiées. Toutefois, les arguments en faveur d'un lien entre radiosensibilité et CDB sont généralement indirects. À partir de 23lignées fibroblastiques humaines (5témoins et 18hypersensibles), nous décrivons une relation quantifiée entre la radiosensibilité intrinsèque et les cassures résiduelles de l'ADN et des chromosomes. La mort d'un fibroblaste humain irradié est associée à 6,6 CDB et 1,3 cassure chromosomique non réparées.
Energy Technology Data Exchange (ETDEWEB)
Pouthier, Th
2006-12-15
To understand the mechanisms of interaction of ionizing radiation with living tissues exposed to low and protracted doses remains a major issue for risk evaluation. The response cannot be found in epidemiological studies because the only available data concern accidental exposures to high doses of radiation. The natural exposure represents the main source of exposure in the daily life, just before the medical sources (radiology, radiotherapy). In addition, this kind of exposure is very difficult to reproduce in vitro by irradiating cell lines. The method per preference is based on random irradiation of cell populations. The mean number of particles having traversed cells is then calculated on the basis of Poisson statistics. In addition to inevitable multiple impacts, the numerous potential intracellular targets (nuclei, cytoplasm), the indirect effects induced by the impact of particles on neighbouring cells or simply the extracellular targets, constitute phenomena that make more complex the interpretation of experimental data. A charged particle microbeam was developed at C.E.N.B.G. to perform the targeted irradiation of individual cells with a targeting precision of a few microns. It is possible to deliver a counted number of alpha particles down to the ultimate dose of one alpha per cell, to target predetermined cells and then to observe the response of the neighbouring cells. This facility has been validated during this work on human keratinocyte cells expressing a recombinant nuclear fluorescent protein (histone H2B-GFP). The combination of ion micro-beams with confocal microscopy and numeric quantitative analysis allowed the measurement of DNA double strand breaks via the phosphorylation of the histone H2A.X in individual cells. The mechanisms of DNA reparation and apoptosis induction were also in the scope of those studies. The experimental results obtained during this thesis validate the methodology we have developed by demonstrating the targeting
Energy Technology Data Exchange (ETDEWEB)
Marcinkova-Bencokova, Z
2007-07-15
There are about 6000 new cases of nervous system tumours each year in France. However, the current radio chemotherapeutic approaches against brain tumours remain still insufficient to produce a satisfactory therapeutic index. In parallel, the knowledge of the early radiobiological events has considerably progressed in the last few years. This thesis aims to provide new insights in the molecular and cellular response of brain tumours to radio chemotherapy. This thesis was divided into four stages. Stage 1: a novel DNA double-strand breaks repair pathway depending on the MRE11 protein but independent of the phosphorylation of H2AX emerged from the study of artefacts of the immunofluorescence technique and a systematic analysis of the radiosensitivity of human cells. Stage 2: the radiobiological features of 3 rodent models of glioma among the most used in preclinical trials and of 7 human glioma cell lines were investigated. Functional impairments of the BRCA1 protein in response to radiation and/or cisplatin were observed in the majority of the models tested, raising the question of the role of this protein in the anti-glioma treatments and in glioma genesis. Stage 3: in order to extend our approach to genetic syndromes associated with cerebral tumours predisposition, the radiobiological characteristics of the fibroblasts resulting from patients suffering from neurofibromatosis type 1 (NF1), a pathology associated with a strong incidence of peripheral nervous system tumours, were investigated. NF1 appeared to be a syndrome with moderated radiosensitivity, associated with a weak deficiency of DNA end-joining repair but with a strong activity of MRE11. These results enabled us to propose a preliminary model involving both proteins BRCA1 and NF1. Stage 4: considering the role of BRCA1 in the inhibition of some tyrosine kinase activity and in the response to cisplatin, we tested the radiobiological effects of treatments combining radiation, cisplatin and tyrosine kinase
Études par diffraction de fibres de l'ADN double brin
Forsyth, V. T.; Parrot, I. M.
2005-11-01
L'état fibreux est un état naturel pour les molécules de polymère qui ont tendance à adopter des conformations hélicoïdales régulières plutôt que des structures globulaires caractéristiques à de nombreuses protéines. La diffraction de fibres a donc une application étendue pour l'étude d'une grande variété de polymères biologiques et synthétiques. Ce papier a pour objectif d'illustrer l'étendue générale de la méthode et, en particulier, de démontrer l'impact des sources modernes de rayonnement synchrotron et de faisceaux neutroniques.
Directory of Open Access Journals (Sweden)
Gao H
2003-05-01
Full Text Available CONTEXT: Certain imidazoline drugs stimulate insulin secretion acutely but their longer term effects on the viability of pancreatic beta-cells are less well characterised. Indeed, some reports have suggested that imidazolines can be toxic to beta-cells while others have reported protective effects against other cytotoxic agents. OBJECTIVE: In order to address these discrepancies, the effects of two structurally related imidazolines, efaroxan and idazoxan, on the viability of clonal BRIN-BD11 beta-cells, were compared. DESIGN AND MAIN OUTCOME MEASURES: BRIN-BD11 cells were exposed to test reagents and their viability monitored by measuring cellular reducing ability and DNA fragmentation. Nitric oxide was measured indirectly via medium nitrite formation. RESULTS: Efaroxan (up to 100 micro M did not directly affect BRIN-BD11 cell viability in the absence of other agents and it did not protect these cells against the cytotoxic effects of interleukin-1beta. Indeed, analysis of DNA fragmentation in BRIN-BD11 cells revealed that efaroxan enhanced the level of damage caused by interleukin-1beta. Idazoxan caused a time- and dose-dependent loss of BRIN-BD11 cell viability in the absence of other ligands. This was associated with marked DNA degradation but was not associated with formation of nitric oxide. The effects of idazoxan were insensitive to blockade of alpha(2-adrenoceptors or 5-HT(1A (5-hydroxytryptamine; serotonin receptors. CONCLUSIONS: The results confirm that idazoxan is cytotoxic to beta-cells but show that efaroxan is better tolerated. However, since efaroxan enhanced the cytotoxic effects of interleukin-1beta, it appears that this imidazoline may sensitise BRIN-BD11 cells to the damaging effects of certain cytokines.
Directory of Open Access Journals (Sweden)
Erfanian Reza
2014-06-01
Full Text Available Objective: The use of fibrin adhesives has a broad background in nerve repair. Currently the suboptimal physical properties of singledonor fibrin adhesives have restricted their usage. The present experiment studies the performance and physical characteristics of a modified fibrin glue prepared from single-donor human plasma in the repair of posterior tibial nerve of rat. Methods: Forty Wistar rats were divided into 5 groups; in the control group, tibial nerve was completely transected and no treatment was done, while in the four experimental groups the nerve stumps were reconnected by one suture, three sutures, one suture with fibrin glue and fibrin glue alone respectively. During 8 weeks of follow-up, Tibial Function Index was measured weekly and adhesive strength, inflammation and scar formation were assessed at the end of the study. Results: Nerve stumps dehiscence rate and adhesive strength were similar in all experimental groups and significantly differed from control group (P<0.05. By the end of the eighth follow-up week, functional recovery of one and three sutures groups were signifi cantly higher than groups in which fibrin glue was used for repair (P<0.05. The amount of inflammation and scar tissue formation was similar among all groups. Conclusion: The study results show that the prepared single-donor fibrin adhesive has acceptable mechanical properties which could provide required adhesiveness and hold nerve stumps in the long term; yet, we acknowledge that more studies are needed to improve functional outcome of single donor fi brin adhesive repair. Key words: Rats; Nerve regeneration; Fibrin tissue adhesive; Materials testing
La Madeleine, Carole
Ce memoire est presente a la Faculte de medecine et des sciences de la sante de l'Universite de Sherbrooke en vue de l'obtention du grade de maitre es sciences (M.Sc.) en radiobiologie (2009). Un jury a revise les informations contenues dans ce memoire. Il etait compose de professeurs de la Faculte de medecine et des sciences de la sante soit : Darel Hunting PhD, directeur de recherche (departement de medecine nucleaire et radiobiologie), Leon Sanche PhD, directeur de recherche (departement de medecine nucleaire et radiobiologie), Richard Wagner PhD, membre du programme (departement de medecine nucleaire et radiobiologie) et Guylain Boissonneault PhD, membre exterieur au programme (departement de biochimie). Le 5-bromodeoxyuridine (BrdU), un analogue halogene de la thymidine reconnu depuis les annees 60 comme etant un excellent radiosensibilisateur. L'hypothese la plus repandue au sujet de l'effet radio sensibilisant du BrdU est qu'il augmente le nombre de cassures simple et double brin lorsqu'il est incorpore dans l'ADN de la cellule et expose aux radiations ionisantes. Toutefois, de nouvelles recherches semblent remettre en question les observations precedentes. Ces dernieres etudes ont confirme que le BrdU est un bon radiosensibilisateur, car il augmente les dommages radio-induits dans l'ADN. Mais, c'est en etant incorpore dans une region simple brin que le BrdU radiosensibilise l'ADN. Ces recherches ont egalement revele pour la premiere fois un nouveau type de dommages produits lors de l'irradiation de l'ADN contenant du BrdU : les dimeres interbrins. Le but de ces travaux de recherche est de determiner si la presence de bromodeoxyuridine dans l'ADN augmente l'induction de bris simple et / ou double brin chez les cellules irradiees en utilisant de nouvelles techniques plus sensibles et specifiques que celles utilisees auparavant. Pour ce faire, les essais cometes et la detection des foci H2AX phosphorylee pourraient permettre d'etablir les effets engendres par
Energy Technology Data Exchange (ETDEWEB)
Revaud, D.
2009-06-15
Interstitial Telomeric Sequences (ITS) are over-involved in spontaneous and radiationinduced chromosome aberrations in chinese hamster cells. We have performed a study to investigate the origin of their instability, spontaneously or after low doses irradiation. Our results demonstrate that ITS have a particular chromatin structure: short nucleotide repeat length, less compaction of the 30 nm chromatin fiber, presence of G-quadruplex structures. These features would modulate breaks production and would favour the recruitment of alternative DNA repair mechanisms, which are prone to produce chromosome aberrations. These pathways could be at the origin of chromosome aberrations in ITS whereas NHEJ and HR Double Strand Break repair pathways are rather required for a correct repair in these regions. (author)
Rosen, Charles; Siegel, Edward Carl-Ludwig; Feynman, Richard; Wunderman, Irwin; Smith, Adolph; Marinov, Vesco; Goldman, Jacob; Brine, Sergey; Poge, Larry; Schmidt, Erich; Young, Frederic; Goates-Bulmer, William-Steven; Lewis-Tsurakov-Altshuler, Thomas-Valerie-Genot; Ibm/Exxon Collaboration; Google/Uw Collaboration; Microsoft/Amazon Collaboration; Oracle/Sun Collaboration; Ostp/Dod/Dia/Nsa/W.-F./Boa/Ubs/Ub Collaboration
2013-03-01
Belew[Finding Out About, Cambridge(2000)] and separately full-decade pre-Page/Brin/Google FIRST Siegel-Rosen(Machine-Intelligence/Atherton)-Feynman-Smith-Marinov(Guzik Enterprises/Exxon-Enterprises/A.-I./Santa Clara)-Wunderman(H.-P.) [IBM Conf. on Computers and Mathematics, Stanford(1986); APS Mtgs.(1980s): Palo Alto/Santa Clara/San Francisco/...(1980s) MRS Spring-Mtgs.(1980s): Palo Alto/San Jose/San Francisco/...(1980-1992) FIRST quantum-computing via Bose-Einstein quantum-statistics(BEQS) Bose-Einstein CONDENSATION (BEC) in artificial-intelligence(A-I) artificial neural-networks(A-N-N) and biological neural-networks(B-N-N) and Siegel[J. Noncrystalline-Solids 40, 453(1980); Symp. on Fractals..., MRS Fall-Mtg., Boston(1989)-5-papers; Symp. on Scaling..., (1990); Symp. on Transport in Geometric-Constraint (1990)
Lewis, Chara; Mojsiewicz, Kristin; Pettican, Anneké
2010-01-01
Replication of the self and engagement with liminal spaces has informed our collaborative practice. 3D body scanning, processing and digital printing proffered new methods of engagement as yet uncharted to capture ourselves faithfully. (http://www.brassart.org.uk) Test body scans suggested the potential to reveal public and private aspects of ‘the self’ – representing both the physiological and psychological aspects of a subject. Digitised Doubles was a practice led enquiry ...
Dumont, Ariane
Il a ete demontre que les electrons de basse energie (EBE) peuvent induire des cassures simple brin (CSB) a l'ADN, via la formation d'anions transitoires qui decroissent par attachement dissociatif, ou dans d'autres etats electroniques dissociatifs menant a la fragmentation. Afin d'effectuer une etude complete des effets des electrons de basse energie sur la matiere biologique, il est necessaire de comprendre leur mecanismes d'interaction non seulement avec l'ADN, mais avec les constituants de son environnement. Les histones sont une composante importante de l'environnement moleculaire de l'ADN. Leur charge positive leur permet de s'associer aux groupements phosphate anionique de l'ADN. Le role principal de ces proteines basiques consiste a organiser l'ADN et l'empaqueter afin de former la chromatine. Les cations sont une autre composante importante de la cellule; ils jouent un role dans la stabilisation de la conformation B de l'ADN in vitro par leurs interactions avec les petits et grands sillons de l'ADN, ainsi qu'avec le groupement phosphate charge negativement. Avec les histones, ils participent egalement a la compaction de l'ADN pour former la chromatine. Cette etude a pour but de comprendre comment la presence d'ions organiques (sous forme de Tris et d'EDTA) a proximite de l'ADN modifie le rendement de cassures simple brin induit par les electrons de basse energie. Le Tris et l'EDTA ont-ete choisis comme objet d'etude, puisqu'en solution, ils forment le tampon standard pour solubiliser l'ADN dans les experiences in vitro (10mM Tris, 1mM EDTA). De plus, la molecule Tris possede un groupement amine alors que l'EDTA possede 4 groupements carboxyliques. Ensembles, ils peuvent se comporter comme un modele simple pour les acides amines. Le ratio molaire de 10 :1 de Tris par rapport a l'EDTA a pour but d'imiter le comportement des histones qui sont riches en arginine et lysine, acides amines possedant un groupement amine charge positivement additionnel. Des films d
The Cambridge Double Star Atlas
MacEvoy, Bruce; Tirion, Wil
2015-12-01
Preface; What are double stars?; The binary orbit; Double star dynamics; Stellar mass and the binary life cycle; The double star population; Detecting double stars; Double star catalogs; Telescope optics; Preparing to observe; Helpful accessories; Viewing challenges; Next steps; Appendices: target list; Useful formulas; Double star orbits; Double star catalogs; The Greek alphabet.
... medlineplus.gov/ency/article/007328.htm Double outlet right ventricle To use the sharing features on this page, please enable JavaScript. Double outlet right ventricle (DORV) is a heart disease that is ...
Doubling rational normal curves
Notari, Roberto; Ojeda, Ignacio; Spreafico, Maria Luisa
2008-01-01
In this paper, we study double structures supported on rational normal curves. After recalling the general construction of double structures supported on a smooth curve described in \\cite{fer}, we specialize it to double structures on rational normal curves. To every double structure we associate a triple of integers $ (2r,g,n) $ where $ r $ is the degree of the support, $ n \\geq r $ is the dimension of the projective space containing the double curve, and $ g $ is the arithmetic genus of the...
Double-double effect and coordination number
International Nuclear Information System (INIS)
The original method of interpretation together with its theoretical foundations is developed, making it possible to use location and direction of the double-double (tetrad) effect within the Ln and An series to determine the coordination number (CN) complexes of the f-block elements. The method is applied for potentiometric and radiometric equilibrium studies. It has been pointed and that the decisive factor for the direction of the double-double effect in the case of the Gibbs energy variations is a difference in the CN of the f-element ion between the reaction product complex and that for the reaction substrate the ''regular'' effect for a given tetrad is accompanied by decrease in the CN while the ''reverse'' effect by increase in the CN. (author). 122 refs, 5 tabs, 8 figs
UNILATERAL INCOMPLETE DOUBLE URETER
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Kaini
2013-04-01
Full Text Available ABSTRACT: Double ureter is a result of premature division of t he ureteric bud. The ureters may join in the lower third of their course and open thr ough a common orifice into the bladder. If they open independently into the bladder, the ureter draining the upper pelvis opens into the bladder below the opening of the other ureter. Patie nts with double ureter or double pelvis are more likely to develop urinary infection and calculi .
Barabash, A. S.
2011-01-01
The present status of double beta decay experiments is reviewed. The results of the most sensitive experiments are discussed. Proposals for future double beta decay experiments with a sensitivity to the $$ at the level of (0.01--0.1) eV are considered.
Mohammedi, N
2016-01-01
We study the quantum behaviour of a particle moving in a one-dimensional double well potential. This double well is obtained by gluing together, at the origin, two shifted harmonic oscillator potentials. The Schr\\"odinger equation is exactly solvable. The requirement that discontinuities, in the wavefunction and its first derivative, are absent at the origin, leads to the quantisation of the energy eigenvalues. We also show that oscillations in time take place between two nearby single harmonic oscillator ground states. Finally, the double well potential is augmented by a Dirac delta-function potentials at the origin and the corresponding Schr\\"odinger equation is solved.
... closed during this surgery. Return to main topic: Congenital Heart Disease See on other sites: MedlinePlus https://medlineplus.gov/ency/article/007328.htm Double outlet right ventricle Texas Adult ...
Neutrinoless double electron capture
Kotila, J; Iachello, F
2015-01-01
Direct determination of the neutrino mass is at the present time one of the most important aims of experimental and theoretical research in nuclear and particle physics. A possible way of detection is through neutrinoless double electron capture, $0\
Neutrinoless double beta decay
International Nuclear Information System (INIS)
The physics potential of neutrinoless double beta decay is discussed. Furthermore, experimental considerations as well as the current status of experiments are presented. Finally, an outlook towards the future, work on nuclear matrix elements and alternative processes is given. (author)
Neutrinoless double beta decay
Indian Academy of Sciences (India)
Kai Zuber
2012-10-01
The physics potential of neutrinoless double beta decay is discussed. Furthermore, experimental considerations as well as the current status of experiments are presented. Finally, an outlook towards the future, work on nuclear matrix elements and alternative processes is given.
Dynamics of Double Stochastic Operators
Saburov, Mansoor
2016-03-01
A double stochastic operator is a generalization of a double stochastic matrix. In this paper, we study the dynamics of double stochastic operators. We give a criterion for a regularity of a double stochastic operator in terms of absences of its periodic points. We provide some examples to insure that, in general, a trajectory of a double stochastic operator may converge to any interior point of the simplex.
DEFF Research Database (Denmark)
Kalyanova, Olena
Double-Skin Facades (DSF) are gaining popularity that, in fact, appears to be independent from sturdy critics of the concept in the past years. DSF buildings are being built in Europe and worldwide, DSF concept is being taught at schools of architecture and fully glazed office buildings are being...... to perform the simulations. To fill in the gap of lacking experimental data a range of measurements was carried out in an outdoor, double-skin façade full-scale test facility ‘The Cube'. As a result, three complete sets of experimental data were composed. These are available for external air curtain...... IEA Annex 34/43, subtask E "Double-Skin Facade". The results of empirical validation are discussed in this work. Discussion and analysis of experimental results is carried out. It has lead to hypothesis of recirculation flow phenomenon in the DSF cavity. Finally, a suggestion of a new numerical model...
Jaffe, Arthur
2016-01-01
Here we introduce reflection positive doubles, a general framework for reflection positivity, covering a wide variety of systems in statistical physics and quantum field theory. These systems may be bosonic, fermionic, or parafermionic in nature. Within the framework of reflection positive doubles, we give necessary and sufficient conditions for reflection positivity. We use a reflection-invariant cone to implement our construction. Our characterization allows for a direct interpretation in terms of coupling constants, making it easy to check in concrete situations. We illustrate our methods with numerous examples.
Garaud, Pascale
2014-01-01
Much progress has recently been made in understanding and quantifying vertical mixing induced by double-diffusive instabilities such as fingering convection (usually called thermohaline convection) and oscillatory double-diffusive convection (a process closely related to semiconvection). This was prompted in parts by advances in supercomputing, which allow us to run Direct Numerical Simulations of these processes at parameter values approaching those relevant in stellar interiors, and in parts by recent theoretical developments in oceanography where such instabilities also occur. In this paper I summarize these recent findings, and propose new mixing parametrizations for both processes that can easily be implemented in stellar evolution codes.
International Nuclear Information System (INIS)
The great sensitivity of double beta decay to neutrino mass and right handed currents has motivated many new and exciting attempts to observe this elusive nuclear phenomenon directly. Experiments in operation and other coming on line in the next one or two years are expected to result in order-of-magnitude improvements in detectable half lives for both the two-neutrino and no-neutrino modes. A brief history of double beta decay experiments is presented together with a discussion of current experimental efforts, including a gas filled time projection chamber being used to study selenium-82. (author)
Bargaining with Double Jeopardy
Saul Levmore; Ariel Porat
2011-01-01
Virtually every burden of proof is influenced by a rule regarding relitigation. In criminal law, the prosecutor is prevented from repeatedly drawing from the urn, as it were, by the double-jeopardy rule, which reinforces the beyond-a-reasonable-doubt standard. We suggest that if law were to permit defendants to waive double-jeopardy protection, private and social benefits might follow. The benefits derive from the likelihood that prosecutors--like most people who can take a test but once--ove...
Ahlers, H; Müntinga, H; Wenzlawski, A; Krutzik, M; Tackmann, G; Abend, S; Gaaloul, N; Giese, E; Roura, A; Kuhl, R; Lämmerzahl, C; Peters, A; Windpassinger, P; Sengstock, K; Schleich, W P; Ertmer, W; Rasel, E M
2016-04-29
We employ light-induced double Bragg diffraction of delta-kick collimated Bose-Einstein condensates to create three symmetric Mach-Zehnder interferometers. They rely on (i) first-order, (ii) two successive first-order, and (iii) second-order processes which demonstrate the scalability of the corresponding momentum transfer. With respect to devices based on conventional Bragg scattering, these symmetric interferometers double the scale factor and feature a better suppression of noise and systematic uncertainties intrinsic to the diffraction process. Moreover, we utilize these interferometers as tiltmeters for monitoring their inclination with respect to gravity. PMID:27176520
A CHOLELITHIASIC DOUBLE GALLBLADDER
Directory of Open Access Journals (Sweden)
B. Wani
2009-11-01
Full Text Available Double gallbladder is rare congenital anomaly. It is important to diagnose it preoperatively for which, ultrasound is the preferred modality of imaging. We report a case of 56 years old male patient who presented with recurrent upper abdominal pain and diagnosed as two cholelithiasic gallbladders for which we did cholecystectomy of both. We are reporting this case for its rare occurrence.
DEFF Research Database (Denmark)
Di Nucci, Ezio
2014-01-01
There are some interesting similarities between Aristotle’s ‘mixed actions’ in Book III of the Nicomachean Ethics and the actions often thought to be justifiable with the Doctrine of Double Effect. Here I analyse these similarities by comparing Aristotle’s examples of mixed actions with standard ...
DEFF Research Database (Denmark)
Rosenzweig, Ivana; Fogarasi, András; Johnsen, Birger;
2014-01-01
performance was compared with the double banana (longitudinal bipolar montage, 10-20 array). RESULTS: Adding the inferior temporal electrode chain, computed montages (reference free, common average, and source derivation), and voltage maps significantly increased the sensitivity. Phase maps had the highest...
King, B; Keitel, C H; 10.1038/nphoton.2009.261
2013-01-01
Double-slits provide incoming photons with a choice. Those that survive the passage have chosen from two possible paths which interfere to distribute them in a wave-like manner. Such wave-particle duality continues to be challenged and investigated in a broad range of disciplines with electrons, neutrons, helium atoms, C60 fullerenes, Bose-Einstein condensates and biological molecules. All variants have hitherto involved material constituents. We present a matterless double-slit scenario in which photons generated from virtual electron-positron pair annihilation in head-on collisions of a probe laser field with two ultra-intense laser beams form a double-slit interference pattern. Such electromagnetic fields are predicted to induce material-like behaviour in the vacuum, supporting elastic scattering between photons. Our double-slit scenario presents on the one hand a realisable method to observe photon-photon scattering, and demonstrates on the other, the possibility of both controlling light with light and n...
Neutrinoless Double Beta Decay
Päs, Heinrich
2015-01-01
We review the potential to probe new physics with neutrinoless double beta decay $(A,Z) \\to (A,Z+2) + 2 e^-$. Both the standard long-range light neutrino mechanism as well as short-range mechanisms mediated by heavy particles are discussed. We also stress aspects of the connection to lepton number violation at colliders and the implications for baryogenesis.
Toal, Vincent; Mihaylova, Emilia M.
2009-01-01
This note describes how white light interference fringes can be seen by observing the Moon through a double-glazed window. White light interferometric fringes are normally observed only in a well-aligned interferometer whose optical path difference is less than the coherence length of the light source, which is approximately one micrometer for…
Nitramine Double Base Propellants
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M. M. Bhalerao
1996-10-01
Full Text Available This review paper broadly covers the studies conducted on nitramine double base (DB propellants, particularly in the field of formulations, evaluation, catalysis and combustion mechanism . Addition of RDX and HMX in double base matrix shows relatively low burn rates and high paper index values. Further, the burn rate of this class of propellants enhances in the presence of energetic binders/plasticisers like glycidyl azide polymer. This paper also discusses the combustion mechanism of HMX/RDX-based DB propellants, especially in the presence of catalytic salts. As scanty data is available on extruded nitramine DB propellants, further work is needed in the field of formulation as well as evaluation with a view to generate exhaustive data.
International Nuclear Information System (INIS)
To increase the accuracy of discrimination of true coincidences against the background of accidental ones, circuit has been developed which operates on the principle of dynamic equalization of resolution times of two coincidence circuits. The flowsheet of a 4x6 double-coincidence matrix is given. The principal elements of the matrix are commutators and output signal shapers. The matrix uses 138-series microcircuits. The resolution time of coincidence circuits is 10 ns, the dead time is 25 ns. The results of testing the matrix during experiments under conditions of a high background of accidental coincidences (70-90%) have shown that the accuracy of discrimination of true coincidences with the help of the double-coincidence matrix approximates the accuracy of time-to-digital converters within the limits of the statistical accuracy
Double rupture disc experience
International Nuclear Information System (INIS)
Result of these observations, comparisons and evaluations can be summarized in the following list of concerns regarding the use of double rupture discs coupled to the liquid space of a steam generator that is subjected to a large leak sodium water reaction event. Single rupture disc show delayed collapse characteristics in LLTR Series I and double disc assemblies are presumed to be more complex with additional delay before opening to give pressure relief. Delayed failure increases pressures in the IHTS and must be adequately covered by design requirements. With CRBR design, the first disc may fail only partially reducing the loading on the second disc with the result that relief performance may not meet requirements
Energy Technology Data Exchange (ETDEWEB)
Reyna, D., E-mail: reyna@anl.gov [Argonne National Laboratory, HEP Division, 9700 S. Cass Ave., Argonne, IL 60439 (United States)
2011-12-15
The Double Chooz experiment will be the next reactor based neutrino oscillation measurement. The collaboration has made significant progress toward the initiation of the experimental construction. Here, we present details of the design, testing and development that have been ongoing, as well as the expected schedule for construction and installation of the experiment. We are currently on our target path to begin data taking in 2008.
Double pendulum contact problem
Directory of Open Access Journals (Sweden)
Špička J.
2014-06-01
Full Text Available The work concerns contact problems focused on biomechanical systems modelled by a multibody approach. The example is modelling of impact between a body and an infrastructure. The paper firstly presents algorithm for minimum distance calculation. An analytical approach using a tangential plain perpendicular to an initial one is applied. Contact force generated during impact is compared by three different continuous force models, namely the Hertz’s model, the spring-dashpot model and the non-linear damping model. In order to identify contact parameters of these particular models, the method of numerical optimization is used. Purpose of this method is to find the most corresponding results of numerical simulation to the original experiment. Numerical optimization principle is put upon a bouncing ball example for the purpose of evaluation of desirable contact force parameters. The contact modelling is applied to a double pendulum problem. The equation of motion of the double pendulum system is derived using Lagrange equation of the second kind with multipliers, respecting the contact phenomena. Applications in biomechanical research are hinted at arm gravity motion and a double pendulum impact example.
2016-01-01
Conspectus Pairs of coupled quantum dots with controlled coupling between the two potential wells serve as an extremely rich system, exhibiting a plethora of optical phenomena that do not exist in each of the isolated constituent dots. Over the past decade, coupled quantum systems have been under extensive study in the context of epitaxially grown quantum dots (QDs), but only a handful of examples have been reported with colloidal QDs. This is mostly due to the difficulties in controllably growing nanoparticles that encapsulate within them two dots separated by an energetic barrier via colloidal synthesis methods. Recent advances in colloidal synthesis methods have enabled the first clear demonstrations of colloidal double quantum dots and allowed for the first exploratory studies into their optical properties. Nevertheless, colloidal double QDs can offer an extended level of structural manipulation that allows not only for a broader range of materials to be used as compared with epitaxially grown counterparts but also for more complex control over the coupling mechanisms and coupling strength between two spatially separated quantum dots. The photophysics of these nanostructures is governed by the balance between two coupling mechanisms. The first is via dipole–dipole interactions between the two constituent components, leading to energy transfer between them. The second is associated with overlap of excited carrier wave functions, leading to charge transfer and multicarrier interactions between the two components. The magnitude of the coupling between the two subcomponents is determined by the detailed potential landscape within the nanocrystals (NCs). One of the hallmarks of double QDs is the observation of dual-color emission from a single nanoparticle, which allows for detailed spectroscopy of their properties down to the single particle level. Furthermore, rational design of the two coupled subsystems enables one to tune the emission statistics from single
Colloidal Double Quantum Dots.
Teitelboim, Ayelet; Meir, Noga; Kazes, Miri; Oron, Dan
2016-05-17
Pairs of coupled quantum dots with controlled coupling between the two potential wells serve as an extremely rich system, exhibiting a plethora of optical phenomena that do not exist in each of the isolated constituent dots. Over the past decade, coupled quantum systems have been under extensive study in the context of epitaxially grown quantum dots (QDs), but only a handful of examples have been reported with colloidal QDs. This is mostly due to the difficulties in controllably growing nanoparticles that encapsulate within them two dots separated by an energetic barrier via colloidal synthesis methods. Recent advances in colloidal synthesis methods have enabled the first clear demonstrations of colloidal double quantum dots and allowed for the first exploratory studies into their optical properties. Nevertheless, colloidal double QDs can offer an extended level of structural manipulation that allows not only for a broader range of materials to be used as compared with epitaxially grown counterparts but also for more complex control over the coupling mechanisms and coupling strength between two spatially separated quantum dots. The photophysics of these nanostructures is governed by the balance between two coupling mechanisms. The first is via dipole-dipole interactions between the two constituent components, leading to energy transfer between them. The second is associated with overlap of excited carrier wave functions, leading to charge transfer and multicarrier interactions between the two components. The magnitude of the coupling between the two subcomponents is determined by the detailed potential landscape within the nanocrystals (NCs). One of the hallmarks of double QDs is the observation of dual-color emission from a single nanoparticle, which allows for detailed spectroscopy of their properties down to the single particle level. Furthermore, rational design of the two coupled subsystems enables one to tune the emission statistics from single photon
Directory of Open Access Journals (Sweden)
Liu
2005-11-01
Full Text Available The Double Star Programme (DSP was first proposed by China in March, 1997 at the Fragrant Hill Workshop on Space Science, Beijing, organized by the Chinese Academy of Science. It is the first mission in collaboration between China and ESA. The mission is made of two spacecraft to investigate the magnetospheric global processes and their response to the interplanetary disturbances in conjunction with the Cluster mission. The first spacecraft, TC-1 (Tan Ce means "Explorer", was launched on 29 December 2003, and the second one, TC-2, on 25 July 2004 on board two Chinese Long March 2C rockets. TC-1 was injected in an equatorial orbit of 570x79000 km altitude with a 28° inclination and TC-2 in a polar orbit of 560x38000 km altitude. The orbits have been designed to complement the Cluster mission by maximizing the time when both Cluster and Double Star are in the same scientific regions. The two missions allow simultaneous observations of the Earth magnetosphere from six points in space. To facilitate the comparison of data, half of the Double Star payload is made of spare or duplicates of the Cluster instruments; the other half is made of Chinese instruments. The science operations are coordinated by the Chinese DSP Scientific Operations Centre (DSOC in Beijing and the European Payload Operations Service (EPOS at RAL, UK. The spacecraft and ground segment operations are performed by the DSP Operations and Management Centre (DOMC and DSOC in China, using three ground station, in Beijing, Shanghai and Villafranca.
Iacovazzo, D; Bianchi, A; Lugli, F; Milardi, D; Giampietro, A; Lucci-Cordisco, E; Doglietto, F; Lauriola, L; De Marinis, L
2013-04-01
Double pituitary adenomas represent up to 2.6 % of pituitary adenomas in large surgical series and up to 3.3 % of patients with Cushing's disease have been found to have double or multiple pituitary adenomas. We report the case of a 60-year-old male patient whose medical history began in 2002 with erectile dysfunction; hyperprolactinemia was found and MRI showed a 6-mm area of delayed enhancement in the lateral portion of the right pituitary lobe. Treatment with cabergoline was started with normalization of prolactin levels; the following MRI, performed in 2005 and 2008, showed shrinkage of the pituitary lesion. In 2005, the patient began to manifest weight gain, hypertension, and facial plethora, but no further evaluations were done. In January 2010, the patient came to our attention and underwent multiple tests that suggested Cushing's disease. A new MRI was negative. Bilateral inferior petrosal sinus sampling showed significant pituitary-to-peripheral ratio and, in May 2010, the patient underwent exploratory pituitary surgery with evidence of a 1-2-mm white-coloured midline area compatible with pituitary adenoma that was surgically removed. Post-operatively, the patient's clinical conditions improved with onset of secondary hypoadrenalism. The histologic examination confirmed a pituitary adenoma (immunostaining was found to be positive for ACTH and negative for prolactin). We report the case of an ACTH-producing microadenoma metachronous to a prolactin secreting microadenoma although not confirmed histologically, shrunk by medical treatment. A review of data in the literature regarding double or multiple pituitary adenomas has also been done. PMID:23325364
International Nuclear Information System (INIS)
The government-owned Hydro-Quebec was instructed to take certain actions, one of which was to increase profits. The company has published a report describing its plans for 1998-2002. The company expects to increase sales and double its income over the five years. Hydro-Quebec (which produces or purchases 97% of the electricity consumed in the province) will freeze prices until April 2002. Environmental considerations and liaison with local communities are included in the 5-year plan. The company expects to invest c$1.2B in international markets over the five years and C$20M per year are earmarked for research. (UK)
Bousso, Raphael
2013-01-01
The firewall paradox is often presented as arising from double entanglement, but I argue that more generally the paradox is double purity. Near-horizon modes are purified by the interior, in the infalling vacuum. Hence they cannot also be pure alone, or in combination with any third system, as demanded by unitarity. This conflict arises independently of the Page time, for entangled and for pure states. It implies that identifications of Hilbert spaces cannot resolve the paradox. Traditional complementarity requires the unitary identification of infalling matter with a scrambled subsystem of the Hawking radiation. Extending this map to the infalling vacuum overdetermines the out-state. More general complementarity maps ("A=R_B", "ER=EPR") founder when the near-horizon zone is pure. I argue that pure-zone states span the microcanonical ensemble, and that this suffices to make the horizon a special place. I advocate that the ability to detect the horizon locally, rather than the degree or probability of violence...
Double Field Theory Inspired Cosmology
Wu, Houwen
2014-01-01
Double field theory proposes a generalized spacetime action possessing manifest T-duality on the level of component fields. We calculate the cosmological solutions of double field theory with vanishing Kalb-Ramond field. It turns out that double field theory provides a more consistent way to construct cosmological solutions than the standard string cosmology. We find two sets of solutions in double field theory cosmology, respecting or violating the strong (weak) constraint. Both sets of solutions naturally contain the pre- and post-big bang evolutions in one single line element. This novel feature opens a window for possible resolution of the cosmic amnesia. We also demonstrate that the scale factor duality in the standard string cosmology is nothing but the T-duality in double field theory. The scale dual dilatons in the standard string cosmology is simply the usual diffeomorphic scalar dilaton $\\phi$ and dual diffeomorphic scalar dilaton $\\tilde\\phi$ in double field theory. Furthermore, we identify the "sh...
Apple Valley Double Star Workshop
Brewer, Mark
2015-05-01
The High Desert Astronomical Society hosts an annual double star workshop, where participants measure the position angles and separations of double stars. Following the New Generation Science Standards (NGSS), adopted by the California State Board of Education, participants are assigned to teams where they learn the process of telescope set-up and operation, the gathering of data, and the reduction of the data. Team results are compared to the latest epoch listed in the Washington Double Star Catalog (WDS) and papers are written for publication in the Journal of Double Star Observations (JDSO). Each team presents a PowerPoint presentation to their peers about actual hands-on astronomical research.
Institute of Scientific and Technical Information of China (English)
LUO Xin-Lian; BAI Hua; ZHAO Lei
2008-01-01
Regardless of the formation mechanism, an exotic object, the double degenerate star (DDS), is introduced and investigated, which is composed of baryonic matter and some unknown fermion dark matter. Different from the simple white dwarfs (WDs), there is additional gravitational force provided by the unknown fermion component inside DDSs, which may strongly affect the structure and the stability of such kind of objects. Many possible and strange observational phenomena connecting with them are concisely discussed. Similar to the normal WD, this object can also experience thermonuclear explosion as type Ia supernova explosion when DDS's mass exceeds the maximum mass that can be supported by electron degeneracy pressure. However, since the total mass of baryonic matter can be much lower than that of WD at Chandrasekhar mass limit, the peak luminosity should be much dimmer than what we expect before, which may throw a slight shadow on the standard candle of SN Ia in the research of cosmology.
Generalized double Pareto shrinkage
Armagan, Artin; Lee, Jaeyong
2011-01-01
We propose a generalized double Pareto prior for Bayesian shrinkage estimation and inferences in linear models. The prior can be obtained via a scale mixture of Laplace or normal distributions, forming a bridge between the Laplace and Normal-Jeffreys' priors. While it has a spike at zero like the Laplace density, it also has a Student's t-like tail behavior. Bayesian computation is straightforward via a simple Gibbs sampling algorithm. We investigate the properties of the maximum a posteriori estimator, as sparse estimation plays an important role in many problems, reveal connections with some well-established regularization procedures and show some asymptotic results. The performance of the prior is tested through simulations and application to real data.
International Nuclear Information System (INIS)
Double mode pulsation is a very pervasive phenomenon in stars all over the Hertzsprung-Russell diagram. In order of increasing radius, examples are: ZZ Ceti stars, the sun, the delta Scuti stars, RR Lyrae variables, the β Cephei variables and those related to them, Cepheids, and maybe even the Mira stars. These many modes have been interpreted as both radial and nonradial modes, but in many cases the actual mode has not been clearly identified. Yellow giants seem to be the most simple pulsators with a large majority of the RR Lyrae variables and Cepheids showing only one pulsation period. We limit this review to those very few cases for classical Cepheids and RR Lyrae variables which display two modes. For these we know many facts about these stars, but the actual cause of the pulsation in two modes simultaneously remains unknown
Bergshoeff, Eric A; Penas, Victor A; Riccioni, Fabio
2016-01-01
We present the dual formulation of double field theory at the linearized level. This is a classically equivalent theory describing the duals of the dilaton, the Kalb-Ramond field and the graviton in a T-duality or O(D,D) covariant way. In agreement with previous proposals, the resulting theory encodes fields in mixed Young-tableau representations, combining them into an antisymmetric 4-tensor under O(D,D). In contrast to previous proposals, the theory also requires an antisymmetric 2-tensor and a singlet, which are not all pure gauge. The need for these additional fields is analogous to a similar phenomenon for "exotic" dualizations, and we clarify this by comparing with the dualizations of the component fields. We close with some speculative remarks on the significance of these observations for the full non-linear theory yet to be constructed.
Nuclear magnetic gamma double resonance
International Nuclear Information System (INIS)
A number of problems corresponding to different variants of experiments using nuclear magnetic-gamma double resonance (NMGDR) are theoretically investigated. Calculation is carried out and its results are compared to experimental ones concerning NMGDR for tantalum. Time dynamics of the source or scatterer nucleus sublevel populations under double resonance conditions with non-uniform initial population of this nucleus sublevels is studied
Stability of weak double layers
International Nuclear Information System (INIS)
The transverse stability of weak double-layers in plasmas with a two-temperature electron component is investigated. The double layers appear as shocklike solutions of the modified Korteweg-de Vries (mKdV) equation with a negative coefficient of the cubic nonlinear term. The investigations are performed both for an unmagnetized and a magnetized plasma. In the former case the two-dimensional evolution of the double layer is governed by a modified Kadomtsev-Petviashvili (mKP) equation and the double layer is unstable. In a magnetized plasma the two-dimensional evolution is governed by a modified Zakharov-Kuznetsov (mZK) equation and the double layer is found to be stable. (au)
Lasserre, Thierry; Double Chooz Collaboration
2016-05-01
I report the latest results from the Double Chooz experiment on the θ13 neutrino mixing angle. Two detectors are located at distances of 400 m and 1050 m from the reactor cores of the Chooz nuclear power station (France) to measure the disappearance of electron antineutrinos. The far detector has been taking data since 2011, accumulating a live time of 467.90 days (66.5 GW-ton-year). In this article we focus on the latest measurement using neutrino-induced neutron capture on hydrogen. A new analysis improved the signal efficiency and reduced the backgrounds and systematic uncertainties, leading to sin2 2θ 13 = 0.095+0.039 -0.038. When combined with the Gadolinium-based analysis this leads to sin2 2θ13 = 0.088+0.33 -0.033. The distortion from the prediction above a visible energy of 4 MeV is confirmed. The near detector started data taking in 2014 and first results shall be reported in 2016.
International Nuclear Information System (INIS)
This report describes the remediation activities performed and the results of postremediation radiation surveys conducted at the Double Tracks site, located on Range 71 North, of the Nellis Air Force Range (NAFR) in southern Nevada. This remediation was conducted from June to August 1996 in accordance with the Interim Corrective Action Plan (ICAP) to remediate the site to an acceptable risk to human health and the environment. Soil with a total transuranic activity greater than 200 picoCuries per gram (pCi/g) was excavated, shipped to the Nevada Test Site (NTS), and disposed at the Area 3 Radioactive Waste Management Site (RWMS). A total of 52.3 grams of plutonium (Pu) with an activity of 5.12 Curies was disposed. The concrete pad at ground zero (GZ) was broken up, placed in a Sealand reg-sign container, and shipped to the NTS Area 6 decontamination pad. Additionally, approximately 10 m3 (350 ft3) of soil containing small chips of concrete was shipped to the NTS Area 6 decontamination pad. The concrete and soil/concrete mixture will be further characterized prior to disposal. At the time this report was written, characterization samples were being collected, with analytical results expected in January 1997. It is anticipated that the material will be disposed in mid-1997. This remediation is an interim action because final cleanup levels have not been established
Laser double Doppler flowmeter
Poffo, L.; Goujon, J.-M.; Le Page, R.; Lemaitre, J.; Guendouz, M.; Lorrain, N.; Bosc, D.
2014-05-01
The Laser Doppler flowmetry (LDF) is a non-invasive method for estimating the tissular blood flow and speed at a microscopic scale (microcirculation). It is used for medical research as well as for the diagnosis of diseases related to circulatory system tissues and organs including the issues of microvascular flow (perfusion). It is based on the Doppler effect, created by the interaction between the laser light and tissues. LDF measures the mean blood flow in a volume formed by the single laser beam, that penetrate into the skin. The size of this measurement volume is crucial and depends on skin absorption, and is not directly reachable. Therefore, current developments of the LDF are focused on the use of always more complex and sophisticated signal processing methods. On the other hand, laser Double Doppler Flowmeter (FL2D) proposes to use two laser beams to generate the measurement volume. This volume would be perfectly stable and localized at the intersection of the two laser beams. With FL2D we will be able to determine the absolute blood flow of a specific artery. One aimed application would be to help clinical physicians in health care units.
Crespo-Anadón, J I
2014-01-01
The latest results from the Double Chooz experiment on the neutrino mixing angle $\\theta_{13}$ are presented. A detector located at an average distance of 1050 m from the two reactor cores of the Chooz nuclear power plant has accumulated a live time of 467.90 days, corresponding to an exposure of 66.5 GW-ton-year (reactor power $\\times$ detector mass $\\times$ live time). A revised analysis has boosted the signal efficiency and reduced the backgrounds and systematic uncertainties compared to previous publications, paving the way for the two detector phase. The measured $\\sin^2 2\\theta_{13} = 0.090^{+0.032}_{-0.029}$ is extracted from a fit to the energy spectrum. A deviation from the prediction above a visible energy of 4 MeV is found, being consistent with an unaccounted reactor flux effect, which does not affect the $\\theta_{13}$ result. A consistent value of $\\theta_{13}$ is measured in a rate-only fit to the number of observed candidates as a function of the reactor power, confirming the robustness of the ...
Double chambered right ventricle
Energy Technology Data Exchange (ETDEWEB)
Cho, Chul Koo; Yu, Yun Jeong; Yeon, Kyung Mo; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)
1983-12-15
Fourteen cases of double chambered right ventricle were diagnosed angiographically and of these nine cases were confirmed after operation and autopsy at Seoul National University Hospital in recent four years since 1979. The clinical and radiological findings with the emphasis on the cinecardiographic findings were analysed. The summaries of the analysis are as follows: 1. Among 14 cases, 6 cases were male and 8 cases were female. Age distribution was from 4 years to 36 years. 2. In chest x-ray findings, pulmonary vascularity was increased in 8 cases, decreased in 4 cases, and normal in 2 cases. Cardiomegaly was observed in 8 cases and other showed normal heart size. 3. In cinecardiography, 11 cases had interventricular septal defect. Among these 11 cases, VSD located in proximal high pressure chamber was in 2 cases and located in distal low pressure chamber was in 9 cases. 4. The location of aberrant muscle bundle in sinus portion of right ventricle was in 8 cases. In the rest 6 cases, the aberrant muscle bundle was located below the infundibulum of right ventricle. 5. For accurate diagnosis and differential diagnosis with other congenital cardiac anomalies such as Tetralogy of Fallot or isolated pulmonic stenosis, biplane cineangiography and catheterization is an essential procedure.
Double acts, theatrical couples, and Split Britches' 'Double Agency'
Harris, Geraldine
2002-01-01
In 2001 Split Britches presented a double bill entitled Double Agency, consisting of one new piece, Miss Risque, and one already in their repertoire, It's a Small House and We've Lived in It Always--both works having been created in collaboration with the Cold Ensemble. In this article, Geraldine Harris re-stages her earlier encounter with Small House, in the light of seeing it again as part of the double bill, as a means of examining a number of issues concerning the work of Split Britches i...
International Nuclear Information System (INIS)
A solid state digital system (FCR 101) was employed in our comparative evaluation of the image quality of conventional versus digital techniques in the study of colon by means of double-contrast enema. Sixty patients were examined with a single AP view, using digital radiography with 100% radiation dose and progressive 50% and 75% reductions; the radiographs thus obtained were then compared with the corresponding conventional ones. The examined parameters were organ profile and mucosal pattern. Each digital and conventional radiographs was evaluated by 2 independent radiologists and a value is given to each parameter i.e., 1=good, 2=sufficient, 3=insufficient. Upon comparison of the average values obtained for digital and conventional radiographs in optimal conditions and with a dose reduced by 50%, the digital technique was seen to give a more detailed and accurate representation of both low-contrast mucosal pattern and of organ profile. With the dose reduced by 75%, a slight increase was observed in background noise which caused a slight loss in image definition, but this did not reduce image readability with respect to conventional radiographs. To conclude, the digital method with a 50% exposure reduction is to be preferred in the examination of the colon, especially in pediatric radiology; furthermore, since this technique allows better detailing at lower contrast, it is ot be preferred in the study of the pathologic conditions affecting mainly/only the mucosal pattern-e.g., cancer, ulcerative colitis, Crohn's disease, and so on. An exposure dose reduced by 75% may be used for following lesions previously diagnosed and when a less detailed depiction of the mucosal pattern is enough
International Nuclear Information System (INIS)
It is usually argued that in the double-slit experiment the so-called additive pattern should be seen if the electrons are considered to be particles passing either through one slit or the other but not both (the mutual-exclusion hypothesis) and if a quantum mechanics yields probabilities that combine according to the standard rules; from the fact that the interference pattern is observed instead, it is concluded that quantal probabilities have a fundamentally different character, that it is impossible to find which slit the electron passed through that quantum systems have no-well defined trajectories, or that boolean logic must be given up in favour of a non-distributive quantum logic. Here a form of the argument given by fine (1972) is analyzed and related to the physical evidence. It is shown that of the three suppositions that the argument requires in addition to the mutual-exclusion hypothesis in order to arrive at the additive pattern, one must be abandoned: the supposition that the probability P(XσA) for an electron to reach the probability of reaching X when only slit a is open. Experimental and theoretical reasons are given for supposing that the behaviour of electrons on going through a slit is affected by the opening or closing of a nearby slit, and it is shown that these effects acquire a simple and natural explanation in a new theory, still in process of development, namely stochastic electrodynamics. For electromagnetic waves, on the other hand, it is experimentally possible (and even simple, with holographic techniques) to determine which slit a photon has passed through and still retain the interference pattern, in clear contradiction to a very common assertion. The implications of this difference between light and electrons are discussed. (Author)
Aspects of the Doubled Worldsheet
Driezen, Sibylle; Thompson, Daniel C
2016-01-01
We clarify the relation between various approaches to the manifestly T-duality symmetric string. We explain in detail how the PST covariant doubled string arises from an unusual gauge fixing. We pay careful attention to the role of "spectator" fields in this process and also show how the T-duality invariant doubled dilaton emerges naturally. We extend these ideas to non-Abelian T-duality and show they give rise to the duality invariant formalism based on the semi-Abelian Drinfeld Double. We then develop the N=(0,1) supersymmetric duality invariant formalism.
Google speaks secrets of the world's greatest billionaire entrepreneurs, Sergey Brin and Larry Page
Lowe, Janet
2009-01-01
Praise for Google Speaks "It''s not hard to see that Google is a phenomenal company....At Geico, we pay these guys a whole lot of money for this and that key word."-Warren Buffett "Google rocks. It raised my perceived IQ by about 20 points."-Wes Boyd, President of Moveon.Org "Google is my rapid response research assistant. It''s the Swiss Army knife of information retrieval."-Lloyd Grove, columnist, Portfolio.com "Who''s afraid of Google? Everyone."-Wired magazine "Writers of the past had absinthe, whiskey or heroin. I have Google."-Michael Chabon, author of The Amazing Adventures of Kavalier and Clay
Steve Jobs, Larry Page ja Sergei Brin teavad iga mu liigutust / Jan Jõgis-Laats
Jõgis-Laats, Jan
2011-01-01
iPhone on vähemalt 2010. a. juunist jälginud uusima operatsioonisüsteemi kasutajate telefoni liikumist. Nutitelefonides on tohutult andmeid, mis võõraste inimeste kätte sattudes võivad telefoniomanikule kahju teha. Soovitusi, kuidas oma andmeid kaitsta. Kümme nutitelefoniga seotud suuremat riski
Directory of Open Access Journals (Sweden)
John J. Lattanzio
2010-01-01
Full Text Available Problem statement: The vertex double-critical conjecture that the only vertex double-critical graph is the complete graph has remained unresolved for over forty years. The edge analogue of this conjecture has been proved. Approach: It was observed that if the chromatic number decreases by two upon the removal of a 2-matching, then the 2-matching comprises four vertices which determine an induced subgraph isomorphic to the complete graph on four vertices. This observation was generalized to t-matchings. Results: In this note, it has been shown that the only edge double-critical graph is the complete graph. Conclusion/Recommendations: An alternate proof that the only edge double-critical graph is the complete graph has been obtained. Moreover, the result has been obtained independently.
International Nuclear Information System (INIS)
A novel prism has been devised which can be used in place of the ‘flag’ in an optical shadow-sensing type of displacement sensor, for example. In this way, theoretically the displacement sensitivity of the sensor can be doubled. Such a prism has been manufactured, and its displacement-doubling property has been verified. - Highlights: • A new type of glass prism doubles linear displacement of optical beams. • Optical operation has been verified. • Light beams enter and exit at normal incidence to prism's windows. • Optical path length through prism remains constant, as prism is moved. • Designed to double the displacement sensitivity of knife-edge shadow sensors
Directory of Open Access Journals (Sweden)
Francois P. Viljoen
2015-03-01
Full Text Available The Gospel of Matthew was written during a period of dispute between the Matthean community and their fellow Jews, with the Pharisees playing a leading role. The Matthean community was heir to the same scriptures as its opponents. They continued to have a firm commitment to the Torah, but they developed a distinctive understanding of it based on Jesus’ teaching. The formation of this community is investigated in this article, considering the Mediterranean perspectives of group-oriented societies prevalent in the first century. Such a group provided a sense of self and an interactive support system, where love functioned to bind the group together. The subordinates showed their undivided loyalty towards their superiors because of the favours they received from them, whilst they supported and cared for other members within the group as they care for themselves. Reading the double love commandment of Matthew 22:34−40 from this perspective reveals significant aspects of the community’s identity with regard to their commitment to God and their view of their neighbours.Die Dubbele Liefdesgebod. Die Matteusevangelie is gedurende ’n periode van konfliktussen die Matteusgemeenskap en mede-Jode geskryf met die Fariseërs in ’n leidende rol. Die Matteusgemeenskap het van dieselfde geskrifte as hulle opponente gebruik gemaak. Hulle was steeds aan die Torah lojaal, maar het ’n unieke interpretasie daarvan gehuldig, gebaseer op die onderrig van Jesus. In hierdie artikel word die vorming van die Matteusgemeenskap ondersoek met inagneming van die Mediterreense beskouing van die groepgeoriënteerde gemeenskappe wat tipies van die eerste eeu was. So ’n groep het aan individue ’n bewustheid van eie waarde verskaf te midde van ’n interaktiewe ondersteuningsisteem waarin liefde as samebindende faktor gefunksioneer het. Ondergeskiktes het onverdeelde lojaliteit teenoor hulle meerderes betoon vanweë die gunste wat hulle van die meerderes geniet het
Methods of Mitigating Double Taxation
Lindhe, Tobias
2002-01-01
This paper presents a comprehensive overview of existing methods of mitigating double taxation of corporate income within a standard cost of capital model. Two of the most well-known and most utilized methods, the imputation and the split rate systems, do not mitigate double taxation in corporations where the marginal investment is financed with retained earnings. However, all methods are effective when the marginal investment is financed with new share issues. The corporate tax rate, fiscal ...
Study of {sup 19}C by breakup reactions; Etude du {sup 19}C par reactions de cassure
Energy Technology Data Exchange (ETDEWEB)
Liegard, Emmanuel [Lab. de Physique Corpusculaire, Caen Univ., 14 Caen (France)
1998-01-07
To date studies of halo nuclei have been principally focussed on the A 11 systems {sup 11}Li and {sup 11}Be. The evolution of the properties of the halo with the mass of the system and the binding energy and angular momentum of the halo nucleons is a question of fundamental importance. It was in this spirit that the present study of {sup 19}C (S{sub n} = 240 {+-} 100 keV) was undertaken. The experiment was performed at GANIL using a secondary {sup 19}C beam ({approx_equal} 15 pps at 36 MeV/nucleon) produced via fragmentation. The experimental setup which included the neutron array DEMON, provided for identification of the core-breakup and dissociation reaction channels. In the first case, a very narrow single neutron angular distribution (FWHM = 64 {+-} 17 MeV/c) was observed for {sup 19}C, in contrast to that found for three `reference` nuclei {sup 21}N, {sup 22}O and {sup 24}F (FWHM {approx_equal} 165 MeV/c). This result could be interpreted within the framework of the core-breakup reaction model of a one-neutron halo nucleus. The results obtained for dissociation, while supporting the existence of the halo, indicated that it is not well developed. In addition, a comparison between the present results, the parallel momentum distributions for the core ({sup 18}C) and theoretical predictions have allowed conclusions to be drawn regarding the configuration of the valence neutron. In particular, a purely 2s{sub 1/2} of 1d{sub 5/2} configuration is excluded and mixing, possible with core excited states, must be considered. A probable ground state spin-parity assignment of 3{sup +}/2 or 5{sup +}/2 is suggested. (author) 150 refs., 278 figs., 28 tabs.
Predicting Neutrinoless Double Beta Decay
Hirsch, M; Valle, J W F; Moral, A V; Ma, Ernest
2005-01-01
We give predictions for the neutrinoless double beta decay rate in a simple variant of the A_4 family symmetry model. We show that there is a lower bound for the neutrinoless double beta decay amplitude even in the case of normal hierarchical neutrino masses, corresponding to an effective mass parameter |m_{ee}| >= 0.17 \\sqrt{\\Delta m^2_{ATM}}. This result holds both for the CP conserving and CP violating cases. In the latter case we show explicitly that the lower bound on |m_{ee}| is sensitive to the value of the Majorana phase. We conclude therefore that in our scheme, neutrinoless double beta decay may be accessible to the next generation of high sensitivity experiments.
Double zeta values, double Eisenstein series, and modular forms of level 2
Kaneko, Masanobu; Tasaka, Koji
2011-01-01
We study the double shuffle relations satisfied by the double zeta values of level 2, and introduce the double Eisenstein series of level 2 which satisfy the double shuffle relations. We connect the double Eisenstein series to modular forms of level 2.
Detecting Double Compressed JPEG Images
Czech Academy of Sciences Publication Activity Database
Mahdian, Babak; Saic, Stanislav
Rostrevor : Curran Associates, Inc, 2010, P12. ISBN 978-1-84919-207-1. [3rd International Conference on Imaging for Crime Detection and Prevention (ICDP-09). London (GB), 03.12.2009-03.12.2009] R&D Projects: GA ČR GA102/08/0470 Institutional research plan: CEZ:AV0Z10750506 Keywords : Image forensics * Blind forgery detection * double jpeg compression Subject RIV: IN - Informatics, Computer Science http://library.utia.cas.cz/separaty/2011/ZOI/mahdian-detecting double compressed jpeg images.pdf
Double beta decay: present status
Barabash, A. S.
2008-01-01
The present status of double beta decay experiments (including the search for $2\\beta^{+}$, EC$\\beta^{+}$ and ECEC processes) are reviewed. The results of the most sensitive experiments are discussed. Average and recommended half-life values for two-neutrino double beta decay are presented. Conservative upper limits on effective Majorana neutrino mass and the coupling constant of the Majoron to the neutrino are established as $ < 0.75$ eV and $ < 1.9 \\cdot 10^{-4}$, respectively. Proposals fo...
Magnetoresistance stories of double perovskites
Indian Academy of Sciences (India)
Abhishek Nag; Sugata Ray
2015-06-01
Tunnelling magnetoresistance (TMR) in polycrystalline double perovskites has been an important research topic for more than a decade now, where the nature of the insulating tunnel barrier is the core issue of debate. Other than the nonmagnetic grain boundaries as conventional tunnel barriers, intragrain magnetic antiphase boundaries (APB) as well as magnetically frustrated grain surfaces have also been proposed to act as tunnel barriers in Sr2FeMoO6. In this review, the present state of the debate has been discussed briefly and how the physical state of the material can affect the magnetoresistance signal of double perovskites in many different ways has been pointed out.
Attosecond Double-Slit Experiment
International Nuclear Information System (INIS)
A new scheme for a double-slit experiment in the time domain is presented. Phase-stabilized few-cycle laser pulses open one to two windows (slits) of attosecond duration for photoionization. Fringes in the angle-resolved energy spectrum of varying visibility depending on the degree of which-way information are measured. A situation in which one and the same electron encounters a single and a double slit at the same time is observed. The investigation of the fringes makes possible interferometry on the attosecond time scale. From the number of visible fringes, for example, one derives that the slits are extended over about 500 as
Attosecond double-slit experiment.
Lindner, F; Schätzel, M G; Walther, H; Baltuska, A; Goulielmakis, E; Krausz, F; Milosević, D B; Bauer, D; Becker, W; Paulus, G G
2005-07-22
A new scheme for a double-slit experiment in the time domain is presented. Phase-stabilized few-cycle laser pulses open one to two windows (slits) of attosecond duration for photoionization. Fringes in the angle-resolved energy spectrum of varying visibility depending on the degree of which-way information are measured. A situation in which one and the same electron encounters a single and a double slit at the same time is observed. The investigation of the fringes makes possible interferometry on the attosecond time scale. From the number of visible fringes, for example, one derives that the slits are extended over about 500 as. PMID:16090782
Attosecond double-slit experiment
Lindner, F.; Schaetzel, M. G.; Walther, H.; Baltuska, A.; Goulielmakis, E.; Krausz, F.; Milosevic, D. B; BAUER, D; Becker, W.; Paulus, G G
2005-01-01
A new scheme for a double-slit experiment in the time domain is presented. Phase-stabilized few-cycle laser pulses open one to two windows (``slits'') of attosecond duration for photoionization. Fringes in the angle-resolved energy spectrum of varying visibility depending on the degree of which-way information are observed. A situation in which one and the same electron encounters a single and a double slit at the same time is discussed. The investigation of the fringes makes possible interfe...
Institute of Scientific and Technical Information of China (English)
Xiaoyun MO; Jieming ZHOU; Hui OU; Xiangqun YANG
2013-01-01
Given a new Double-Markov risk model DM =(μ,Q,v,H; Y,Z) and Double-Markov risk process U ={U(t),t ≥ 0}.The ruin or survival problem is addressed.Equations which the survival probability satisfied and the formulas of calculating survival probability are obtained.Recursion formulas of calculating the survival probability and analytic expression of recursion items are obtained.The conclusions are expressed by Q matrix for a Markov chain and transition probabilities for another Markov Chain.
Directory of Open Access Journals (Sweden)
Špringer J.
2013-07-01
Full Text Available Previously (Progr. Phys., 2013, v. 2, 105–106, one introduced the double surface model to explain the heterogeneous curvature of the present world. In this paper one investigates the strength of the mentioned concept in the light of forming the stable electron orbits around the atom nucleus. The conclusion is that the nature of the elliptic side of the proposed double surface oﬀers the possibility of providing the uniform motion of the electron on the atom orbit as well as prevents the electron falling into the nucleus.
Constraining neutrinoless double beta decay
International Nuclear Information System (INIS)
A class of discrete flavor-symmetry-based models predicts constrained neutrino mass matrix schemes that lead to specific neutrino mass sum-rules (MSR). We show how these theories may constrain the absolute scale of neutrino mass, leading in most of the cases to a lower bound on the neutrinoless double beta decay effective amplitude.
Energy Technology Data Exchange (ETDEWEB)
Gueroult, Renaud; Fisch, Nathaniel J. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Rax, Jean-Marcel [Laboratoire d' optique appliquée-LOA, Ecole Polytechnique, Chemin de la Hunière, 91761 Palaiseau Cedex (France)
2014-02-15
Various mass filter concepts based on rotating plasmas have been suggested with the specific purpose of nuclear waste remediation. We report on a new rotating mass filter combining radial separation with axial extraction. The radial separation of the masses is the result of a “double-well” in effective radial potential in rotating plasma with a sheared rotation profile.
Eight Arguments against Double Effect
DEFF Research Database (Denmark)
Di Nucci, Ezio
I offer eight arguments against the Doctrine of Double Effect, a normative principle according to which in pursuing the good it is sometimes morally permissible to bring about some evil as a side-effect or merely foreseen consequence: the same evil would not be morally justified as an intended...
Double Star Mission Starts Countdown
Institute of Scientific and Technical Information of China (English)
无
2003-01-01
@@ As of July, scientists at the CAS Center for Space Science and Applied Research (CSSAR) have been busy modulating and testing the payloads that will be onboard a space exploration satellite, marking the start of the countdown for China's Double Star Project.
Stepenshchikov D. G.; Voytekhovsky Yu. L.
2016-01-01
Various distributions of double carbon bonds in the fullerenes have been considered in the paper from the point that they are absent in the pentagonal rings. The appropriate classification of the fullerenes has been built. The results may be used when modeling the fullerenes of a given topology and calculating their physical-chemical properties
A biphotons double slit experiment
Brida, G.; Cagliero, E.; Falzetta, G.; Gramegna, M. Genovese M.; Predazzi, E.
2003-01-01
In this paper we present a double slit experiment where two undistinguishable photons produced by type I PDC are sent each to a well defined slit. Data about the diffraction and interference patterns for coincidences are presented and discussed. An analysis of these data allows a first test of standard quantum mechanics against de Broglie-Bohm theory.
Biphoton double-slit experiment
International Nuclear Information System (INIS)
In this paper we present a double-slit experiment where two indistinguishable photons produced by type-I parametric down-conversion are each sent to a well-defined slit. Data about the diffraction and interference patterns for coincidences are presented and discussed. An analysis of these data allows a test of standard quantum mechanics against the de Broglie-Bohm theory
Simoson, Andrew J.
2009-01-01
This article presents a fun activity of generating a double-minded fractal image for a linear algebra class once the idea of rotation and scaling matrices are introduced. In particular the fractal flip-flops between two words, depending on the level at which the image is viewed. (Contains 5 figures.)
2009-01-01
Läti suursaadik Ingrida Levrence avas esimese Double Coffee kohviku Hiina pealinnas Pekingi südames. Rahvusvaheline kohvikukett kavatseb laieneda mõne kohviku võrra igal aastal. Seni tegutsetakse Lätis, Eestis, Leedus, Ukrainas ja Valgevenes
Double purchasing power parity problem.
Augusztinovics M
1986-01-01
ILO pub-WEP pub. Economic theory working paper on monetary policy to deal with double purchasing power economic disparity between countries with weak local currency and those with strong currencies - argues that price structures are related to fundamental economic conditions as determined by productivity and employment, and that there cannot be a single exchange rate for primary and secondary products. References, statistical tables.
Double layers and double wells in arbitrary degenerate plasmas
Akbari-Moghanjoughi, M.
2016-06-01
Using the generalized hydrodynamic model, the possibility of variety of large amplitude nonlinear excitations is examined in electron-ion plasma with arbitrary electron degeneracy considering also the ion temperature effect. A new energy-density relation is proposed for plasmas with arbitrary electron degeneracy which reduces to the classical Boltzmann and quantum Thomas-Fermi counterparts in the extreme limits. The pseudopotential method is employed to find the criteria for existence of nonlinear structures such as solitons, periodic nonlinear structures, and double-layers for different cases of adiabatic and isothermal ion fluids for a whole range of normalized electron chemical potential, η0, ranging from dilute classical to completely degenerate electron fluids. It is observed that there is a Mach-speed gap in which no large amplitude localized or periodic nonlinear excitations can propagate in the plasma under consideration. It is further revealed that the plasma under investigation supports propagation of double-wells and double-layers the chemical potential and Mach number ranges of which are studied in terms of other plasma parameters. The Mach number criteria for nonlinear waves are shown to significantly differ for cases of classical with η0 0 regimes. It is also shown that the localized structure propagation criteria possess significant dissimilarities for plasmas with adiabatic and isothermal ions. Current research may be generalized to study the nonlinear structures in plasma containing positrons, multiple ions with different charge states, and charged dust grains.
Monocular Elevation Deficiency - Double Elevator Palsy
... Español Condiciones Chinese Conditions Monocular Elevation Deficiency/ Double Elevator Palsy En Español Read in Chinese What is monocular elevation deficiency (Double Elevator Palsy)? Monocular Elevation Deficiency, also known by the ...
Five-photon double ionization of helium
Li, Y.; Pindzola, M. S.; Colgan, J.
2016-03-01
A time-dependent close-coupling method is used to calculate the five-photon double ionization of He. It is found that the generalized cross section used in the past for two-photon double ionization of He cannot be extended to five-photon double ionization of He. Therefore only five-photon double ionization probabilities that depend on specific radiation field pulses can be calculated.
Minimal Doubling and Point Splitting
International Nuclear Information System (INIS)
Minimally-doubled chiral fermions have the unusual property of a single local field creating two fermionic species. Spreading the field over hypercubes allows construction of combinations that isolate specific modes. Combining these fields into bilinears produces meson fields of specific quantum numbers. Minimally-doubled fermion actions present the possibility of fast simulations while maintaining one exact chiral symmetry. They do, however, introduce some peculiar aspects. An explicit breaking of hyper-cubic symmetry allows additional counter-terms to appear in the renormalization. While a single field creates two different species, spreading this field over nearby sites allows isolation of specific states and the construction of physical meson operators. Finally, lattice artifacts break isospin and give two of the three pseudoscalar mesons an additional contribution to their mass. Depending on the sign of this mass splitting, one can either have a traditional Goldstone pseudoscalar meson or a parity breaking Aoki-like phase.
International Nuclear Information System (INIS)
We report a quantum eraser experiment which actually uses a Young double slit to create interference. The experiment can be considered an optical analogy of an experiment proposed by Scully, Englert, and Walther [Nature (London) 351, 111 (1991)]. One photon of an entangled pair is incident on a Young double slit of appropriate dimensions to create an interference pattern in a distant detection region. Quarter-wave plates, oriented so that their fast axes are orthogonal, are placed in front of each slit to serve as which-path markers. The quarter-wave plates mark the polarization of the interfering photon and thus destroy the interference pattern. To recover interference, we measure the polarization of the other entangled photon. In addition, we perform the experiment under 'delayed erasure' circumstances
Double-implanted subvolt JFETs
International Nuclear Information System (INIS)
The fabrication and performance characteristics of double-implanted subvolt pinchoff JFETs suitable for low-voltage micropower analog applications are described. The process requires the addition of only one mask to the standard bipolar process. Typical devices exhibit a breakdown voltage of 5.5 V, gate leakage in the low pA range, a pinchoff voltage of about 0.5 V and a cutoff frequency of 10.4 MHz. (author)
Review of double beta experiments
Sarazin, X.
2012-01-01
C13-10-22.1 International audience This paper gives a review of the double beta experimental techniques and projects, in the search for the Majorana neutrino. The purpose of this review is to detail, for each technique, the different origins of background, how they can be identified, and how they can be reduced. Advantages and limitations of the different techniques are discussed. 1. Introduction The neutrino is one of the most puzzling elementary particle with very unique properties. I...
Multiphoton double ionization of barium
International Nuclear Information System (INIS)
The authors report the observation of the wavelength spectrum of the double ionization of Ba from ∼ 280 nm to nearly 700 nm, using laser pulses 5ns long of peak intensity ∼ 1010 W/cm2. All the strong resonances can be assigned to Ba+ transitions, and many of the assignments have been verified by pump-probe techniques. Thus, the Ba++ observed is due to sequential ionization. The shortest wavelengths used are not as effective as λ ∼ 500 nm
Double wall underground storage tank
Energy Technology Data Exchange (ETDEWEB)
Canaan, E.B. Jr.; Wiegand, J.R.; Bartlow, D.H.
1993-07-06
A double wall underground storage tank is described comprising: (a) a cylindrical inner wall, (b) a cylindrical outer wall comprising plastic resin and reinforcement fibers, and (c) a layer of spacer filaments wound around the inner wall, the spacer filaments separating the inner and outer walls, and the spacer filaments being at least partially surrounded by voids to enable liquids to flow along the filaments.
Double anodization experiments in tantalum
Energy Technology Data Exchange (ETDEWEB)
Albella, J.M.; Fernandez, M.; Gomez-Aleixandre, C.; Martinez-Duart, J.M.; Montero, I.
1985-10-01
Based on our previous model of anodization, a new formula is given for the relation between the breakdown voltage V /SUB B/ during the anodic oxidation of tantalum and the anodization parameters. The formula predicts the well known diminution of V /SUB B/ with the logarithm of the electrolyte concentration. The model also explains the experimentally-observed fact that V /SUB B/ is solely determined by the latter electrolyte in double anodization experiments.
Neutrinoless Double Beta Decay Experiments
Zuber, K.
2014-01-01
Neutrinoless double beta decay is the only process known so far able to test the neutrino intrinsic nature: its experimental observation would imply that the lepton number is violated by two units and prove that neutrinos have a Majorana mass components, being their own anti-particle. While several experiments searching for such a rare decay have been performed in the past, a new generation of experiments using different isotopes and techniques have recently released their results or are taki...
Generalized Double Ring Network Structures
DEFF Research Database (Denmark)
Pedersen, Jens Myrup; Patel, A.; Knudsen, Thomas Phillip; Madsen, Ole Brun
This paper describes and studies generalizations of the well-known double ring network structures. Two classes of structures are studied, the N2R(p; q) and N2R(p; q; r) structures, of which the former is a special case of the well known Generalized Petersen Graphs. Basic properties of these...... distances and diameters is evaluated and compared to the performance of double rings. This comparison shows that the N2R(p; q) structures are superior to the double rings with regard to distances. For example, a N2R(p; q) structure with 1000 nodes has average distance 12 and diameter 18, while a similar...... structures are shown, indicating that they forma suitable base for future access network infrastructures. The first result is that every N2R(p; q; r) structure is isomorphic to a N2R(p; q) structure N2R(p; q'), and it is shown how q' is determined. Consequently, the rest of the paper focuses on the N2R(p; q...
Pair extended coupled cluster doubles
Henderson, Thomas M; Scuseria, Gustavo E
2015-01-01
The accurate and efficient description of strongly correlated systems remains an important challenge for computational methods. Doubly occupied configuration interaction (DOCI), in which all electrons are paired and no correlations which break these pairs are permitted, can in many cases provide an accurate account of strong correlations, albeit at combinatorial computational cost. Recently, there has been significant interest in a method we refer to as pair coupled cluster doubles (pCCD), a variant of coupled cluster doubles in which the electrons are paired. This is simply because pCCD provides energies nearly identical to those of DOCI, but at mean-field computational cost (disregarding the cost of the two-electron integral transformation). Here, we introduce the more complete pair extended coupled cluster doubles (pECCD) approach which, like pCCD, has mean-field cost and reproduces DOCI energetically. We show that unlike pCCD, pECCD also reproduces the DOCI wave function with high accuracy. Moreoever, pEC...
Revisiting double Dirac delta potential
Ahmed, Zafar; Kumar, Sachin; Sharma, Mayank; Sharma, Vibhu
2016-07-01
We study a general double Dirac delta potential to show that this is the simplest yet still versatile solvable potential to introduce double wells, avoided crossings, resonances and perfect transmission (T = 1). Perfect transmission energies turn out to be the critical property of symmetric and anti-symmetric cases wherein these discrete energies are found to correspond to the eigenvalues of a Dirac delta potential placed symmetrically between two rigid walls. For well(s) or barrier(s), perfect transmission (or zero reflectivity, R(E)) at energy E=0 is non-intuitive. However, this has been found earlier and called the ‘threshold anomaly’. Here we show that it is a critical phenomenon and we can have 0≤slant R(0)\\lt 1 when the parameters of the double delta potential satisfy an interesting condition. We also invoke a zero-energy and zero curvature eigenstate (\\psi (x)={Ax}+B) of the delta well between two symmetric rigid walls for R(0)=0. We resolve that the resonant energies and the perfect transmission energies are different and they arise differently.
Double-Critical Graphs and Complete Minors
DEFF Research Database (Denmark)
Kawarabayashi, Ken-ichi; Pedersen, Anders Sune; Toft, Bjarne
2010-01-01
A connected $k$-chromatic graph $G$ is double-critical if for all edges $uv$ of $G$ the graph $G - u - v$ is $(k-2)$-colourable. The only known double-critical $k$-chromatic graph is the complete $k$-graph $K_k$. The conjecture that there are no other double-critical graphs is a special case of...
Turner doubles and generalized Schur algebras
Evseev, Anton; Kleshchev, Alexander
2016-01-01
Turner's Conjecture describes all blocks of symmetric groups and Hecke algebras up to derived equivalence in terms of certain double algebras. With a view towards a proof of this conjecture, we develop a general theory of Turner doubles. In particular, we describe doubles as explicit maximal symmetric subalgebras of certain generalized Schur algebras and establish a Schur-Weyl duality with wreath product algebras.
Double aortic arch with double aneuploidy-rare anomaly in combined Down and Klinefelter syndrome
M.F. Gerretsen; W. Peelen; L.A.J. Rammeloo; D.R. Koolbergen; J. Hruda
2009-01-01
A 14-month-old boy with double aneuploidy and a double aortic arch suffered from frequently recurrent severe feeding and respiratory problems. Chromosomal analysis showed a 48,XXY + 21 karyotype: a double aneuploidy of Down syndrome (DS) and Klinefelter syndrome (KS). Only four cases of double aneup
Heat generation in double layer capacitors
Energy Technology Data Exchange (ETDEWEB)
Schiffer, Julia; Linzen, Dirk; Sauer, Dirk Uwe [Electrochemical Energy Conversion and Storage Systems Group, Institute for Power Electronics and Electrical Drives (ISEA), RWTH Aachen University, Jaegerstrasse 17-19, D-52066 Aachen (Germany)
2006-09-29
Thermal management is a key issue concerning lifetime and performance of double layer capacitors and battery technologies. Double layer capacitor modules for hybrid vehicles are subject to heavy duty cycling conditions and therefore significant heat generation occurs. High temperature causes accelerated aging of the double layer capacitors and hence reduced lifetime. To investigate the thermal behavior of double layer capacitors, thermal measurements during charge/discharge cycles were performed. These measurements show that heat generation in double layer capacitors is the superposition of an irreversible Joule heat generation and a reversible heat generation caused by a change in entropy. A mathematical representation of both parts is provided. (author)
On The Cycle Double Cover Problem
Ghassab, Ali
2012-01-01
In this paper, for each graph G, a free edge set F is defined. To study the existence of cycle double cover, the naive cycle double cover of G and F have been defined and studied. In the main theorem, the paper, based on the Kuratowski minor properties, presents a condition to guarantee the existence of a naive cycle double cover for couple (G,F). As a result, the cycle double cover conjecture has been concluded. Moreover, Goddyn's conjecture - asserting if C is a cycle in bridgeless graph G, there is a cycle double cover of G containing C - will have been proved.
Forecasting in continuous double auction
Czech Academy of Sciences Publication Activity Database
Šmíd, Martin
Hradec Kralové : Gaudeamus, 2005 - (Skalská, H.), s. 358-363 ISBN 978-80-7041-535-1. [Mathematical Methods in Economics 2005 /23./. Hradec Králové (CZ), 14.09.2005-16.09.2005] R&D Projects: GA ČR GA402/04/1294; GA ČR GD402/03/H057 Grant ostatní: GA UK(CZ) 454/2004/AEK/FSV Institutional research plan: CEZ:AV0Z10750506 Keywords : limit order markets * continuous double auction * price and volume Subject RIV: AH - Economics
Experiments on double beta decay
International Nuclear Information System (INIS)
The Double Beta Decay, and especially (ββ)0ν mode, is an excellent test of Standard Model as well as of neutrino physics. From experimental point of view, a very large number of different techniques are or have been used increasing the sensitivity of this experiments quite a lot (the factor of 104 in the last 20 years). In future, in spite of several difficulties, the sensitivity would be increased further, keeping the interest of this very important process. (author) 4 figs., 5 tabs., 21 refs
AGI doubles minority geoscience scholarships
The American Geological Institute, Alexandria, Va., has had a significant increase in funds available for minority geoscience scholarships for the 1990-1991 academic year. The number of scholarships awarded this year has more than doubled from a total of 36 in 1989-90 to 80 available for 1990-1991.The increase is due largely to a grant from the National Science Foundation. Total value of the awards, which will be given to undergraduate and graduate geoscience students, will be $221,000. For 1989--990 the total value was $36,750.
Experiments on double beta decay
Energy Technology Data Exchange (ETDEWEB)
Busto, J. [Neuchatel Univ. (Switzerland). Inst. de Physique
1996-11-01
The Double Beta Decay, and especially ({beta}{beta}){sub 0{nu}} mode, is an excellent test of Standard Model as well as of neutrino physics. From experimental point of view, a very large number of different techniques are or have been used increasing the sensitivity of this experiments quite a lot (the factor of 10{sup 4} in the last 20 years). In future, in spite of several difficulties, the sensitivity would be increased further, keeping the interest of this very important process. (author) 4 figs., 5 tabs., 21 refs.
Progress of Double Star Program
Institute of Scientific and Technical Information of China (English)
LIU Zhenxing; CAO Jinbin
2006-01-01
The Double Star Programme (DSP) is the first joint space mission between China and ESA. The mission, which is made of two spacecraft, is designed to investigate the magnetospheric global processes and their response to the interplanetary disturbances in conjunction with the Cluster mission. The first spacecraft, TC-1 (Tan Ce means "Explorer"), was launched on 30 December 2003, and the second one, TC-2, on 25 July 2004 on board two Chinese Long March 2C. Due to the importance of and success of DSP, both CNSA and ESA approved the extension of DSP. This paper presents DSP mission and some important scientific results made based on the data of DSP.
Booster double harmonic setup notes
Energy Technology Data Exchange (ETDEWEB)
Gardner, C. J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.
2015-02-17
The motivation behind implementing a booster double harmonic include the reduced transverse space charge force from a reduced peak beam current and reduced momentum spread of the beam, both of which can be achieved from flattening the RF bucket. RF capture and acceleration of polarized protons (PP) is first set up in the single harmonic mode with RF harmonic h=1. Once capture and acceleration have been set up in the single harmonic mode, the second harmonic system is brought on and programmed to operate in concert with the single harmonic system.
Semiconductor double quantum dot micromaser.
Liu, Y-Y; Stehlik, J; Eichler, C; Gullans, M J; Taylor, J M; Petta, J R
2015-01-16
The coherent generation of light, from masers to lasers, relies upon the specific structure of the individual emitters that lead to gain. Devices operating as lasers in the few-emitter limit provide opportunities for understanding quantum coherent phenomena, from terahertz sources to quantum communication. Here we demonstrate a maser that is driven by single-electron tunneling events. Semiconductor double quantum dots (DQDs) serve as a gain medium and are placed inside a high-quality factor microwave cavity. We verify maser action by comparing the statistics of the emitted microwave field above and below the maser threshold. PMID:25593187
Challenges in Double Beta Decay
Directory of Open Access Journals (Sweden)
Oliviero Cremonesi
2014-01-01
Full Text Available In the past ten years, neutrino oscillation experiments have provided the incontrovertible evidence that neutrinos mix and have finite masses. These results represent the strongest demonstration that the electroweak Standard Model is incomplete and that new Physics beyond it must exist. In this scenario, a unique role is played by the Neutrinoless Double Beta Decay searches which can probe lepton number conservation and investigate the Dirac/Majorana nature of the neutrinos and their absolute mass scale (hierarchy problem with unprecedented sensitivity. Today Neutrinoless Double Beta Decay faces a new era where large-scale experiments with a sensitivity approaching the so-called degenerate-hierarchy region are nearly ready to start and where the challenge for the next future is the construction of detectors characterized by a tonne-scale size and an incredibly low background. A number of new proposed projects took up this challenge. These are based either on large expansions of the present experiments or on new ideas to improve the technical performance and/or reduce the background contributions. In this paper, a review of the most relevant ongoing experiments is given. The most relevant parameters contributing to the experimental sensitivity are discussed and a critical comparison of the future projects is proposed.
International Nuclear Information System (INIS)
Numerical and in some degree laboratory experiments suggest the existence of at least two different kinds of time-independent double layers: a strictly monotonic transition of the electrostatic potential and a transition accompanied by a negative spike at the low potential side (ion acoustic DL). An interpretation of both is presented in terms of analytic BGK modes. The first class of DLs commonly observed in voltage- or beam-driven plasmas needs for its existence beam-type distributions satisfying a Bohm criterion. The potential drop is at least of the order of Tsub(e), and stability arguments favour currents which satisfy the Langmuir condition. The second class found in current-driven plasma simulations is correlated with ion holes. This latter kind of nonlinear wave-solutions is linearly based on the slow ion-acoustic mode and exists due to a vortex-like distortion of the ion distribution in the thermal range. During the growth of an ion hole which is triggered by ion-acoustic fluctuations, the partial reflection of streaming electrons causes different plasma states on both sides of the potential dip and makes the ion hole asymmetric giving rise to an effective potential drop. This implies that the amplitude of this second type of double layers has an upper limit of 1-2 Tsub(e) and presumes a temperature ratio of Tsub(e)/Tsub(i) > or approximately 3 in coincidence with the numerical results. (Auth.)
Double Dirac cones in phononic crystals
Li, Yan
2014-07-07
A double Dirac cone is realized at the center of the Brillouin zone of a two-dimensional phononic crystal (PC) consisting of a triangular array of core-shell-structure cylinders in water. The double Dirac cone is induced by the accidental degeneracy of two double-degenerate Bloch states. Using a perturbation method, we demonstrate that the double Dirac cone is composed of two identical and overlapping Dirac cones whose linear slopes can also be accurately predicted from the method. Because the double Dirac cone occurs at a relatively low frequency, a slab of the PC can be mapped onto a slab of zero refractive index material by using a standard retrieval method. Total transmission without phase change and energy tunneling at the double Dirac point frequency are unambiguously demonstrated by two examples. Potential applications can be expected in diverse fields such as acoustic wave manipulations and energy flow control.
Liposomes in Double-Emulsion Globules
Wang, Qing; Tan, Grace; Lawson, Louise B.; John, Vijay T.; Papadopoulos, Kyriakos D.
2010-01-01
Tubular liposomes containing a hydrophilic model compound (fluorescein sodium salt, FSS) were entrapped inside the internal aqueous phase (W1) of water-in-oil-in-water (W1/O/W2) double-emulsion globules. Our hypothesis was that the oil membrane of double emulsions can function as a layer of protection to liposomes and their contents and thus better control their release. Liposomes were prepared in bulk, and their release was observed microscopically from individual double-emulsion globules. T...
Applications of the Fast Double Bootstrap
MacKinnon, James G.
2006-01-01
The fast double bootstrap, or FDB, is a procedure for calculating bootstrap P values that is much more computationally efficient than the double bootstrap itself. In many cases, it can provide more accurate results than ordinary bootstrap tests. For the fast double bootstrap to be valid, the test statistic must be asymptotically independent of the random parts of the bootstrap data generating process. This paper presents simulation evidence on the performance of FDB tests in three cases of in...
Theoretical aspects of double beta decay
International Nuclear Information System (INIS)
Considerable effort has been expended recently in theoretical studies of double beta decay. Much of this work has focussed on the constraints this process places on gauge theories of the weak interaction, in general, and on the neutrino mass matrix, in particular. In addition, interesting nuclear structure questions have arisen in studies of double beta decay matrix elements. After briefly reviewing the theory of double beta decay, some of the progress that has been made in these areas is summarized. 25 references
Controlled double-slit electron diffraction
Bach, Roger; Pope, Damian; Liou, Sy-Hwang; Batelaan, Herman
2012-01-01
Double-slit diffraction is a corner stone of quantum mechanics. It illustrates key features of quantum mechanics: interference and the particle-wave duality of matter. In 1965, Richard Feynman presented a thought experiment to show these features. Here we demonstrate the full realization of his famous thought experiment. By placing a movable mask in front of a double-slit to control the transmission through the individual slits, probability distributions for single- and double-slit arrangemen...
Sound Generating Mechanism of the Double Bass
Directory of Open Access Journals (Sweden)
F. Pantelić
2013-11-01
Full Text Available This paper deals with the mechanical properties of the double bass and double bass bow. The sound of the instrument, as well as the vibrations of the bow, were recorded while playing. The sound was recorded with a microphone, while a sensor, placed on the bow’s stick, registered its vibrations. By observing these signals, from double bass and bow, the correlation between them was determined in order to explain the bow-string mechanism.
Controlled double-slit electron diffraction
International Nuclear Information System (INIS)
Double-slit diffraction is a corner stone of quantum mechanics. It illustrates key features of quantum mechanics: interference and the particle-wave duality of matter. In 1965, Richard Feynman presented a thought experiment to show these features. Here we demonstrate the full realization of his famous thought experiment. By placing a movable mask in front of a double-slit to control the transmission through the individual slits, probability distributions for single- and double-slit arrangements were observed. Also, by recording single electron detection events diffracting through a double-slit, a diffraction pattern was built up from individual events. (paper)
Three Dimensional Double Layers in Magnetized Plasmas
DEFF Research Database (Denmark)
Jovanovic, D.; Lynov, Jens-Peter; Michelsen, Poul;
1982-01-01
Experimental results are presented which demonstrate the formation of fully three dimensional double layers in a magnetized plasma. The measurements are performed in a magnetized stationary plasma column with radius 1.5 cm. Double layers are produced by introducing an electron beam with radius 0.4...... cm along the magnetic field from one end of the column. The voltage drop across the double layer is found to be determined by the energy of the incoming electron beam. In general we find that the width of the double layer along the external magnetic field is determined by plasma density and beam...
Double-Star Decomposition of Regular Graphs
Akbari, Saieed; Haghi, Shahab; Maimani, Hamidreza; Seify, Abbas
2015-01-01
A tree containing exactly two non-pendant vertices is called a double-star. A double-star with degree sequence $(k_1+ 1, k_2+ 1, 1, \\ldots, 1)$ is denoted by $S_{k_1, k_2}$. We study the edge-decomposition of regular graphs into double-stars. It was proved that every double-star of size $k$ decomposes every $2k$-regular graph. In this paper, we extend this result to $(2k+ 1)$-regular graphs, by showing that every $(2k+ 1)$-regular graph containing two disjoint perfect matchings is decomposed ...
Perspectives on double-excitations in TDDFT
Elliott, Peter; Canahui, Chris; Maitra, Neepa T
2011-01-01
The adiabatic approximation in time-dependent density functional theory (TDDFT) yields reliable excitation spectra with great efficiency in many cases, but fundamentally fails for states of double excitation character. We discuss how double-excitations are at the root of some of the most challenging problems for TDDFT today. We then present new results for (i) the calculation of autoionizing resonances in the helium atom, (ii) understanding the nature of the double excitations appearing in the quadratic response function, and (iii) retrieving double-excitations through a real-time semiclassical approach to correlation in a model quantum dot.
Even symplectic supermanifolds and double field theory
Deser, Andreas
2014-01-01
Over many decades, the word "double" has appeared in various contexts, at times seemingly unrelated. Several have some relation to mathematical physics. Recently, this has become particularly strking in DFT (double field theory). Two 'doubles' that are particularly relevant are double vector bundles and Drinfel'd doubles. The original Drinfel'd double occurred in the contexts of quantum groups and of Lie bialgebras. Quoting T. Voronov: "Double Lie algebroids arose in the works on double Lie groupoids and in connection with an analog for Lie bialgebroids of the classical Drinfel'd double of Lie bialgebras...Suppose $(A,A^*)$ is a Lie bialgebroid over a base $M$... Mackenzie and Roytenberg suggested two different constructions based on the cotangent bundles $T^*A$ and $T^*\\Pi A$, respectively. Here $\\Pi$ is the fibre-wise parity reversal functor." Although the approaches of Roytenberg and of Mackenzie look very different, Voronov establishes their equivalence. We have found Roytenberg's version to be quite cong...
Double photoionization of halogenated benzene
International Nuclear Information System (INIS)
We have experimentally investigated the double-photoionization process in C6BrF5 using monochromatized synchrotron radiation. We compare our results with previously published data for partially deuterated benzene (C6H3D3) over a wide range of photon energies from threshold to 270 eV. A broad resonance in the ratio of doubly to singly charged parent ions at about 65 eV appears shifted in energy compared to benzene data. This shift is due to the difference in the bond lengths in two molecules. A simple model can explain the shape of this resonance. At higher photon energies, we observe another broad resonance that can be explained as a second harmonic of the first resonance
Standard Model Double Field Theory
Choi, Kang-Sin
2015-01-01
We show that, without any extra physical degree introduced, the Standard Model can be readily reformulated as a Double Field Theory. Consequently, the Standard Model can couple to an arbitrary stringy gravitational background in an $\\mathbf{O}(4,4)$ T-duality covariant manner and manifests two independent local Lorentz symmetries, $\\mathbf{Spin}(1,3)\\times\\mathbf{Spin}(3,1)$. While the diagonal gauge fixing of the twofold spin groups leads to the conventional formulation on the flat Minkowskian background, the enhanced symmetry makes the Standard Model more rigid, and also stringy, than it appeared. The CP violating $\\theta$-term is no longer allowed by the symmetry, and hence the strong CP problem is solved. There are now stronger constraints imposed on the possible higher order corrections. We urge experimentalists to test if the quarks and the leptons belong to the same spin class or not.
The tropical double description method
Allamigeon, Xavier; Goubault, Eric
2010-01-01
We develop a tropical analogue of the classical double description method allowing one to compute an internal representation (in terms of vertices) of a polyhedron defined externally (by inequalities). The heart of the tropical algorithm is a characterization of the extreme points of a polyhedron in terms of a system of constraints which define it. We show that checking the extremality of a point reduces to checking whether there is only one minimal strongly connected component in an hypergraph. The latter problem can be solved in almost linear time, which allows us to eliminate quickly redundant generators. We report extensive tests (including benchmarks from an application to static analysis) showing that the method outperforms experimentally the previous ones by orders of magnitude. The present tools also lead to worst case bounds which improve the ones provided by previous methods.
CERN celebrates a double anniversary
2003-01-01
A symposium will celebrate the double anniversary of the observation of neutral currents in 1973 and the discovery of W and Z bosons in 1983. The symposium will also provide an opportunity to discuss future discoveries at CERN. The symposium will be held on 16 September in the Main Auditorium from 9:00 hrs and will be open to the public. If you cannot access the Main Auditorium, the symposium will be broadcast live in the following conference rooms: AB Auditorium II (Bldg 864) in Prévessin IT Auditorium (Bldg 31) AT Auditorium (Bldg 30) You can also follow it online with the Webcast accessible from the CERN home page. See the complete programme under Seminars.
Fan, JiJi; Randall, Lisa; Reece, Matthew
2013-01-01
Based on observational tests and constraints on halo structure, dark matter is generally taken to be cold and essentially collisionless. On the other hand, given the large number of particles and forces in the visible world, a more complex dark sector could be a reasonable or even likely possibility. This hypothesis leads to testable consequences, perhaps portending the discovery of a rich hidden world neighboring our own. We consider a scenario that readily satisfies current bounds that we call Partially Interacting Dark Matter (PIDM). This scenario contains self-interacting dark matter, but it is not the dominant component. Even if PIDM contains only a fraction of the net dark matter density, comparable to the baryonic fraction, the subdominant component's interactions can lead to interesting and potentially observable consequences. Our primary focus will be the special case of Double-Disk Dark Matter (DDDM), in which self-interactions allow the dark matter to lose enough energy to lead to dynamics similar ...
Double trouble at high density:
DEFF Research Database (Denmark)
Gergs, André; Palmqvist, Annemette; Preuss, Thomas G
2014-01-01
history. We explored how different mechanisms behind resource-related plasticity and crowding-related fitness act independently or together, using the water flea Daphnia magna as a case study. For testing hypotheses related to mechanisms of plasticity and crowding stress across different biological levels......Population size is often regulated by negative feedback between population density and individual fitness. At high population densities, animals run into double trouble: they might concurrently suffer from overexploitation of resources and also from negative interference among individuals...... regardless of resource availability, referred to as crowding. Animals are able to adapt to resource shortages by exhibiting a repertoire of life history and physiological plasticities. In addition to resource-related plasticity, crowding might lead to reduced fitness, with consequences for individual life...
Double photoionization of halogenated benzene
Energy Technology Data Exchange (ETDEWEB)
AlKhaldi, Mashaal Q. [Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstr. 36, D-10623 Berlin (Germany); Wehlitz, Ralf, E-mail: rwehlitz@gmail.com [Synchrotron Radiation Center, University of Wisconsin–Madison, Stoughton, Wisconsin 53589 (United States)
2016-01-28
We have experimentally investigated the double-photoionization process in C{sub 6}BrF{sub 5} using monochromatized synchrotron radiation. We compare our results with previously published data for partially deuterated benzene (C{sub 6}H{sub 3}D{sub 3}) over a wide range of photon energies from threshold to 270 eV. A broad resonance in the ratio of doubly to singly charged parent ions at about 65 eV appears shifted in energy compared to benzene data. This shift is due to the difference in the bond lengths in two molecules. A simple model can explain the shape of this resonance. At higher photon energies, we observe another broad resonance that can be explained as a second harmonic of the first resonance.
Double-yoke balanced compressor
International Nuclear Information System (INIS)
A double-yoke balanced compressor for a cryogenic cooler that has only linear motion imparted to balanced piston and cylinder masses. A piston yoke is driven in the linear stroke direction by a piston axially offset crankshaft cam and a cylinder yoke is driven linearly by a cylinder axially offset crankshaft cam that is exactly offset 1800 from the other cam. A large circular bushing in the compressor housing covers the entire outer cylinder head during linear operation to prevent blow by and to guide the cylinder linearly. The lower portion of the piston and cylinder connecting rods fit into linear guides that are further comprised of low molecular weight gas filled cavities to provide additional air bearing smoothness to the linear motion of the piston and cylinder
Double-bootstrap methods that use a single double-bootstrap simulation
Chang, Jinyuan; Hall, Peter
2014-01-01
We show that, when the double bootstrap is used to improve performance of bootstrap methods for bias correction, techniques based on using a single double-bootstrap sample for each single-bootstrap sample can be particularly effective. In particular, they produce third-order accuracy for much less computational expense than is required by conventional double-bootstrap methods. However, this improved level of performance is not available for the single double-bootstrap methods that have been s...
Double layers and circuits in astrophysics
International Nuclear Information System (INIS)
As the rate of energy release in a double layer with voltage DeltaV is P corresponding to IDeltaV, a double layer must be treated part of a circuit which delivers the current I. As neither double layer nor circuit can be derived from magnetofluid models of a plasma, such models are useless for treating energy transfer by menas of double layers. They must be replaced by particle models and circuit theory. A simple circuit is suggested which is applied to the energizing of auroroal particles, to solar flares, and to intergalactic double radio sources. Application to the heliospheric current systems leads to the prediction of two double layers on the sun's axis which may give radiations detectable from earth. Double layers in space should be classified as a new type of celestial object (one example is the double radio sources). It is tentatively suggested in X-ray and gamma-ray bursts may be due to exploding double layers (although annihilation is an alternative energy source). A study of how a number of the most used textbooks in astrophysics treat important concepts like double layers, critical velocity, pinch effects and circuits is made. It is found that students using these textbooks remain essentially ignorant of even the existence of these, in spite of the fact that some of them have been well known for half a centry (e.g., double layers, Langmuir, 1929: pinch effect, Bennet, 1934). The conclusion is that astrophysics is too important to be left in the hands of the astrophysicist. Earth bound and space telescope data must be treated by scientists who are familiar with laboratory and magnetospheric physics and circuit theory, and of course with modern plasma theory. At least by volume the universe consists to more than 99 percent of plasma, and electromagnetic forces are 10/sup39/ time stronger than gravitation
Double charm production in single- and double-parton scattering
Szczurek, Antoni
2015-01-01
We discuss production of two pairs of $c \\bar c$ in proton-proton collisions at the LHC. Both double-parton scattering (DPS) and single-parton scattering (SPS) contributions are included in the analysis. Each step of DPS is calculated within $k_t$-factorization approach which effectively includes some next-to-leading order corrections. The discussed mechanisms unavoidably lead to the production of pairs of mesons: $D_i D_j$ (each containing $c$ quarks) or $\\bar D_i \\bar D_j$ (each containing $\\bar c$ antiquarks). We calculate corresponding differential distribution for $(D^0 D^0$ + $\\bar D^0 \\bar D^0)$ production. Within large theoretical uncertainties the predicted DPS cross section is fairly similar to the cross section measured recently by the LHCb collaboration. We also present first results for the $2 \\to 4$ single-parton scattering $g g \\to c \\bar c c \\bar c$ subprocess for the first time fully within the $k_t$-factorization approach. In this calculation we have used an off-shell matrix element squared ...
Approximate double commutants in von Neumann algebras
Hadwin, Don
2011-01-01
Richard Kadison showed that not every commutative von Neumann subalgebra of a factor von Neumann algebra is equal to its relative double commutant. We prove that every commutative C*-subalgebra of a centrally prime C*-algebra $B$ equals its relative approximate double commutant. If $B$ is a von Neumann algebra, there is a related distance formula.
Perspective: Double Jeopardy--Another Look.
Bolduan, Linda M.; Dailey, Dianne K.
1997-01-01
Explores how a defendant can face a civil action and criminal prosecution for the same act without violating the principle of double jeopardy. For instance, burning down a house can engender criminal prosecution charges and a civil suit from the insurance company. Double jeopardy only applies to criminal actions. (MJP)
Nuclear physics issues in double beta decay
International Nuclear Information System (INIS)
A number of issues in double beta decay are discussed: shell model estimates of 2nu matrix elements, a sum rule for the double Gamow-Teller operator, a comparison of shell model and quasiparticle RPA results, Pontecorvo's Te ratio argument, neutrinoless ββ decay mediated by heavy neutrinos, and the structure of O+ states in Ge isotopes. 24 refs., 3 figs
International Nuclear Information System (INIS)
The double γ decay between θ+n - θ+i of 90Zr was observed. The θ+n level was fed through the decay of 90 Sr. The experimental arrangement consisted of a double coincidence system between the two semiconductor detectors. (A.C.A.S.)
Pion double charge exchange and nuclear structure
International Nuclear Information System (INIS)
Pion double charge exchange to both the double-analog state and the ground state is studied for medium weight nuclei. The relative cross section of these two transitions and the importance of nuclear structure as a function of pion kinetic energy is examined. 16 figs., 5 tabs
The Doubling Moment: Resurrecting Edgar Allan Poe
Minnick, J. Bradley; Mergil, Fernando
2008-01-01
This article expands upon Jeffrey Wilhelm's and Brian Edmiston's (1998) concept of a doubling of viewpoints by encouraging middle level students to use dramatization to take on multiple perspectives, to pose interpretive questions, and to enhance critical inquiry from inside and outside of texts. The doubling moment is both the activation of…
The Double Slit Experiment With Polarizers
Holden, M; Sherry, T N
2011-01-01
The double slit experiment provides a standard way of demonstrating how quantum mechanics works. We consider modifying the standard arrangement so that a photon beam incident upon the double slit encounters a polarizer in front of either one or both of the slits.
Double layer dynamics in a collisionless magnetoplasma
DEFF Research Database (Denmark)
Iizuka, S.; Michelsen, Poul; Juul Rasmussen, Jens;
1985-01-01
Investigations of double layer dynamics are performed in a Q-machine plasma by applying a positive step potential to a cold end-plate collector. The double layer created at the grounded plasma source just after the pulse is applied propagates towards the collector with the plasma flow speed. Large...
Double Eye Brow: A Rare Case Report
Kar, Sudipta; Ghosh, Chiranjit; Bazmi, Badruddin Ahamed; Sarkar, Subrata
2013-01-01
Eye brows are essential for esthetic and functional purposes. Various kinds of eye brows are found in human species. Protective function is one of the important functions of eye brows. Double eye brow is a very rare condition found in human. This case report describes one of the rare cases of double eye brow.
Photometry of Faint Wide Doubles in Hydra
Knapp, Wilfried; Thuemen, Chris; Gould, Ross
2015-11-01
Images of several double stars in Hydra published on the "Double Star Imaging Project" Yahoo Group page suggest magnitude issues compared with the corresponding WDS catalog data per end of 2014. Taking additional images with V and B filters enabled photometry for these pairs, suggesting significant corrections to the old data in WDS.
Dynamical Aspects of Electrostatic Double Layers
DEFF Research Database (Denmark)
Raadu, M.A.; Juul Rasmussen, J.
1988-01-01
Electrostatic double layers have been proposed as an acceleration mechanism in solar flares and other astrophysical objects. They have been extensively studied in the laboratory and by means of computer simulations. The theory of steady-state double layers implies several existence criteria...
Intrateam Communication and Performance in Doubles Tennis
Lausic, Domagoj; Tennebaum, Gershon; Eccles, David; Jeong, Allan; Johnson, Tristan
2009-01-01
Verbal and nonverbal communication is a critical mediator of performance in team sports and yet there is little extant research in sports that involves direct measures of communication. Our study explored communication within NCAA Division I female tennis doubles teams. Video and audio recordings of players during doubles tennis matches captured…
Bifurcation structure of successive torus doubling
Energy Technology Data Exchange (ETDEWEB)
Sekikawa, Munehisa [Department of Information Science, Faculty of Engineering, Utsunomiya University (Japan)]. E-mail: muse@aihara.jst.go.jp; Inaba, Naohiko [Department of Information Science, Faculty of Engineering, Utsunomiya University (Japan)]. E-mail: inaba@is.utsunomiya-u.ac.jp; Yoshinaga, Tetsuya [Department of Radiologic Science and Engineering, School of Health Sciences, The University of Tokushima (Japan)]. E-mail: yosinaga@medsci.tokushima-u.ac.jp; Tsubouchi, Takashi [Institute of Engineering Mechanics and Systems, University of Tsukuba (Japan)]. E-mail: tsubo@esys.tsukuba.ac.jp
2006-01-02
The authors discuss the 'embryology' of successive torus doubling via the bifurcation theory, and assert that the coupled map of a logistic map and a circle map has a structure capable of generating infinite number of torus doublings.
1-Convergence of Complex Double Fourier Series
Indian Academy of Sciences (India)
Kulwinder Kaur; S S Bhatia; Babu Ram
2003-11-01
It is proved that the complex double Fourier series of an integrable function (, ) with coefficients {} satisfying certain conditions, will converge in 1-norm. The conditions used here are the combinations of Tauberian condition of Hardy–Karamata kind and its limiting case. This paper extends the result of Bray [1] to complex double Fourier series.
Directionality Effect in Double Conditionals.
Espino, Orlando; Sánchez-Curbelo, Isana; Bolaños-Medina, Alicia
2015-01-01
Directionality effect in deductive reasoning is a very well-known phenomenon that shows that the percentage of forward or backward inferences that participants make depends on the conditional form used. A new extension of the semantic hypothesis (Oberauer & Wilhelm, 2000) is presented to explain the directionality effect in double conditionals with different directionality. This hypothesis claims that the directional effect depends on which term plays the role of relatum. It also makes several novel claims which have been confirmed in three experiments: Experiments 1 and 2 showed there were more forward than backward inferences when the end-term that played the role of relatum was in the first premise, experiment 1: t (45) = 2.73, p < .01, experiment 2: t (38) = 12.06, p < .05, but there were more backward than forward inferences when the end-term that played the role of relatum was in the second premise, experiment 1: t (45) = 2.84, p < .01, experiment 2: t (38) = 2.21, p < .04. Experiment 3 showed that there was no directional effect when both end-terms played the role of relatum, t (34) = 1.39, p = .17, or when both middle-terms (or neither of the end-terms) played the role of relatum, t (34) = .78, p = .44. These experiments confirmed the predictions of the new extension of the semantic hypothesis. PMID:26239471
Double-sided Relativistic Magnetron
Agafonov, A. V.; Krastelev, E. G.
1997-05-01
A new scheme of a symmetricaly powered relativistic magnetron and several methods of localised electron flow forming in an interaction region are proposed to increase an efficiency of relativistic magnetrons. As will be shown, a very important reason is the effect of nonsymmetric feeding of power from one side of a magnetron, which is typical for experiments. One-sided powering leads to the axial drift of electrons, to the transformation of transverse velocities of electrons to longitudinal one and to the generation of a parasitic e-beam which does not take part in energy exchange between electrons and waves at all. A special driver was designed for double-sided powering of relativistic magnetrons. The proposed system is compact, rigid and capable of reliable operation at high repetition rates, which is advantageous for many applications. Several smooth-bore magnetrons were tested by means of computer simulations using PIC code KARAT. The results showed a dramatical difference between the dynamics of electron flow for one- and two-sided power feeding of a structure under test. Design of a driver and computer simulation results are presented.
Double groups and projective representations
Altmann, S. L.; Herzig, P.
Some problems are discussed in relation to the usual treatment of improper groups through their double groups, in particular the identification (rather than the mere isomorphism) of such groups as C3v and D3. The enhancement of SU(2) by the addition of the inversion is analysed for this purpose. This requires a careful discussion of the behaviour of spinors under inversion and two types of spinors are defined, Cartan and Pauli spinors, that behave differently with respect to inversion, although it is shown that this difference merely entails a choice of gauge in the language of projective representations. A distinction is proposed between the inversion operation and the parity operator: when the former is realized as a binary rotation in 4-space, the latter can be identified with its infinitesimal generator. The passage from SO(3) to O(3) (group of all proper and improper rotations) is studied and a hitherto unknown faithful projective representations of O(3) is given. It is shown how spinor representations can be constructed for improper point groups in either the Cartan or Pauli gauges. A choice of gauge is proposed to ensure agreement with current practice in angular momentum theory and with that in single point groups. As an example, Clebsch-Gordan coefficients are constructed for C3v.
Double layer dynamics in a collisionless magnetoplasma
International Nuclear Information System (INIS)
An experimental investigation of the dynamics of double layers is presented. The experiments are performed in a Q-machine plasma and the double layers are generated by applying a positive step potential to a cold collector plate terminating the plasma column. The double layer is created at the grounded plasma source just after the pulse is applied and it propagates towards the collector with a speed around the ion acoustic speed. When the collector is biased positively, large oscillations are observed in the plasma current. These oscillations are found to be related to a recurring formation and propagation of a double layer. The period of the oscillations is determined by the propagation length of the double layer. The current is limited during the propagation of the double layer by a growing negative potential barrier formed on the low potential tail. Similar phenomena appear when a potential difference is applied between two plasmas in a Q-machine with two sources. In this case a stationary double layer forms in the plasma column, but the low potential tail is subject to 'back and forth' oscillations leading to large amplitude current oscillations. (Auth.)
Fan, JiJi; Katz, Andrey; Randall, Lisa; Reece, Matthew
2013-09-01
Based on observational tests of large scale structure and constraints on halo structure, dark matter is generally taken to be cold and essentially collisionless. On the other hand, given the large number of particles and forces in the visible world, a more complex dark sector could be a reasonable or even likely possibility. This hypothesis leads to testable consequences, perhaps portending the discovery of a rich hidden world neighboring our own. We consider a scenario that readily satisfies current bounds that we call Partially Interacting Dark Matter (PIDM). This scenario contains self-interacting dark matter, but it is not the dominant component. Even if PIDM contains only a fraction of the net dark matter density, comparable to the baryonic fraction, the subdominant component’s interactions can lead to interesting and potentially observable consequences. Our primary focus will be the special case of Double-Disk Dark Matter (DDDM), in which self-interactions allow the dark matter to lose enough energy to lead to dynamics similar to those in the baryonic sector. We explore a simple model in which DDDM can cool efficiently and form a disk within galaxies, and we evaluate some of the possible observational signatures. The most prominent signal of such a scenario could be an enhanced indirect detection signature with a distinctive spatial distribution. Even though subdominant, the enhanced density at the center of the galaxy and possibly throughout the plane of the galaxy (depending on precise alignment) can lead to large boost factors, and could even explain a signature as large as the 130 GeV Fermi line. Such scenarios also predict additional dark radiation degrees of freedom that could soon be detectable and would influence the interpretation of future data, such as that from Planck and from the Gaia satellite. We consider this to be the first step toward exploring a rich array of new possibilities for dark matter dynamics.
Double-contrast knee arthrography
International Nuclear Information System (INIS)
From octber 1989, in Radiology Department of Arcispedale Sant'anna in Ferrara, digital radiographic techniques have been applied to be double-contrast arthrography of the knee. In this preliminary work the diagnostic contribution of computed radiography to arthrographic findings by comparing image quality conventional and digital radiographs using a dedicated Philips unit has been examined. The digital unit is compatible with all the extant radiographic equipment in the department and automatically supplues two images, the first one resembling a conventional radiograph, the second one characterized by broader exposure range that allows a clear visualizzation of soft tissues. To obtain high-quality radiographs the processing curves of the system were modified, in particular by shifting the curve leftward, thus reducing its slope, and by amending the parameters related to spatial frequences. The changes in the reading curves made these images more useful: they were more homogeneous and allowed a better evaluation of fine details. Relative to the second type of images, characterized by both edge enhancement and a broader recording range, it was enough to shift the curve along the X-axis to compensate for a moderate image overexposure. Keeping in mind that the aim of this preliminary work was not compare the two techniques from a diagnostic point of view, in the authors' opinion the two yield similar information for the diagnostic evaluation of meniscal traumas. On the contrary, if the same principles are applied to the evaluation of capsulo-ligamentous components, digital arthrography appears to be more accurate than the conventional technique, the latter being deceptive especially in the evaluation of cruciate ligaments
Double Field Theory: A Pedagogical Review
Aldazabal, Gerardo; Marques, Diego; Nunez, Carmen
2013-01-01
Double Field Theory (DFT) is a proposal to incorporate T-duality, a distinctive symmetry of string theory, as a symmetry of a field theory defined on a double configuration space. The aim of this review is to provide a pedagogical presentation of DFT and its applications. We first introduce some basic ideas on T-duality and supergravity in order to proceed to the construction of generalized diffeomorphisms and an invariant action on the double space. Steps towards the construction of a geomet...
Falsifying Baryogenesis with Neutrinoless Double Beta Decay
Graf, Lukas
2016-01-01
We discuss the relation between lepton number violation at high and low energies, particularly, the constraints on baryogenesis models, which would be implied by an observation of neutrinoless double beta decay. The primordial baryon asymmetry can be washed out by effective lepton number violating operators triggering neutrinoless double beta decay in combination with sphaleron processes. A generic conclusion is that popular models of baryogenesis are excluded if a non-standard mechanism of neutrinoless double beta decay, i.e., other than the standard light neutrino exchange, is observed. Apart from the effective field approach, we also outline the possible extension of our arguments to a general UV-completed model.
The International Double Taxation – Avoiding Methods
Directory of Open Access Journals (Sweden)
Nicoleta Barbuta-Misu
2009-06-01
Full Text Available The paper presents the main causes that determine double taxation, its forms, i.e. the economicdouble taxation and the international legal double taxation, the need for eliminating the double taxation andavoiding methods. In the presentation of the avoidance methods have been used practical examples forcomparison of the tax advantages for income beneficiary between: the total exemption method andprogressive exemption method, on the one hand, and total crediting method and ordinary crediting method,on the other hand, but the comparing of tax reduction between methods of exemption and crediting.
The Drinfeld double gl(n) + tn
International Nuclear Information System (INIS)
We present a self-dual Drinfeld double structure underlying the An series of simple Lie algebras. Such double is constructed through a central extension tn of gl(n), and is obtained by pairing two disjoint solvable subalgebras coming from positive and negative roots. The Cartan-Weyl basis of gl(n) is shown to be completely determined by the compatibility conditions in the double. A natural Lie bialgebra structure on gl(n) is obtained that offers a new perspective for the construction of its quantum deformations
Optimization of a lasertron double output cavity
International Nuclear Information System (INIS)
Double output cavities have been used experimentally to increase the efficiency of high-power klystrons. We have used particle-in-cell simulations with the 2 + 1/2 dimensional code MASK to optimize the design of double output cavities for the lasertron under development at SLAC. We discuss design considerations for double output cavities (e.g., optimum choice of voltages and phases, efficiency, wall interception, breakdown). We describe how one calculates the cavity impedance matrix from the gap voltages and phases. Some results of the effect of varying voltage, perveance, and pulse are reported
Isospin splitting in double isovector excitations
International Nuclear Information System (INIS)
Expressions are derived for the relative locations of the different isospin components of double isovector excitations. The splittings between the isospin components are found to be similar in magnitude to the isospin splittings in single excitations. Formulas are given for the relative strengths for exciting the different isospin components of the double excitations. Energy-weighted centroids are calculated in terms of isovector and isotensor energies. Examples are given, using available data for the double giant-dipole resonance. The Lane potential is found to be similar in magnitude to that for the single giant-dipole resonance
Review of modern double beta decay experiments
Barabash, A. S.
2015-10-01
The review of modern experiments on search and studying of double beta decay processes is done. Results of the most sensitive current experiments are discussed. The main attention is paid to EXO-200, KamLAND-Zen, GERDA-I and CUORE-0 experiments. Modern values of T1/2(2ν) and best present limits on neutrinoless double beta decay and double beta decay with Majoron emission are presented. Conservative limits on effective mass of a Majorana neutrino ( at the level of ˜ 0.01-0.1 eV are discussed.
Double Layer Dynamics in a Collisionless Magnetoplasma
DEFF Research Database (Denmark)
Iizuka, S.; Michelsen, Poul; Juul Rasmussen, Jens; Schrittwieser, R.; Hatakeyama, R.; Saeki, K.; Sato, N.
An experimental investigation of the dynamics of double layers is presented. The experiments are performed in a Q-machine plasma and the double layers are generated by applying a positive step potential to a cold collector plate terminating the plasma column. The double layer is created at the...... grounded plasma source just after the pulse is applied and it propagates towards the collector with a speed around the ion acoustic speed. When the collector is biased positively, large oscillations are obserced in the plasma current. These oscillations are found to be related to a recurring formation and...
BLINOV, Sergey
2015-01-01
In 2003, President of Russia Vladimir Putin set the task of doubling the GDP. However, this task is yet to be accomplished. Why has not this goal been achieved yet? What needs to be done to double Russia’s GDP? To answer these questions is exactly what this paper sets out to do. We can see that it is quite possible to double the GDP, but to do that, it takes an absolutely different perspective of the monetary policy of the Central Bank of Russia.
The Efficiency of Tennis Doubles Scoring Systems
Geoff Pollard; Graham Pollard
2010-01-01
In this paper a family of scoring systems for tennis doubles for testing the hypothesis that pair A is better than pair B versus the alternative hypothesis that pair B is better than A, is established. This family or benchmark of scoring systems can be used as a benchmark against which the efficiency of any doubles scoring system can be assessed. Thus, the formula for the efficiency of any doubles scoring system is derived. As in tennis singles, one scoring system based on the play-the-loser ...
Double-reed exhaust valve engine
Energy Technology Data Exchange (ETDEWEB)
Bennett, Charles L.
2015-06-30
An engine based on a reciprocating piston engine that extracts work from pressurized working fluid. The engine includes a double reed outlet valve for controlling the flow of low-pressure working fluid out of the engine. The double reed provides a stronger force resisting closure of the outlet valve than the force tending to open the outlet valve. The double reed valve enables engine operation at relatively higher torque and lower efficiency at low speed, with lower torque, but higher efficiency at high speed.
Double contrast barium meal and acetylcysteine
International Nuclear Information System (INIS)
In a prospective double blind study, acetylcysteine, a local and systemic respiratory tract mucolytic agent, or a placebo, were given to 100 patients prior to a double contrast barium meal to decrease the gastric mucus viscosity and to make the mucus layer thinner, in order to permit barium to outline the furrows surrounding the areae gastricae instead of the overlying thick mucus. However, acetylcysteine failed to improve either visualization of the areae gastricae or the general quality of the double contrast barium meal. (orig.)
Three step double layers in the laboratory. [plasma physics
Bailey, Andrew, III; Hershkowitz, Noah
1988-01-01
A new class of stationary double layer structure, with three or more distinct steps, is demonstrated in the laboratory. A large monotonic potential increase results from a series of smaller double layers. In many respects, these double layer structures resemble those inferred from satellite measurements of auroral double layers. This new class of double layer appears to depend on turbulence for its existence and to be a hybrid structure, intermediate between anomalous resistivity and BGK double layers.
Preparation of uranium ingots from double fluorides
International Nuclear Information System (INIS)
A simple method has been developed for the preparation of uranium double fluorides and has given a new impetus to the study of the reduction of these compounds with a view to obtaining very pure uranium ingots. This reduction can be carried out using calcium or magnesium as the reducing agent, this latter metal being very interesting from the practical point of view. A comparative study of the heat balances of the reduction processes for the double fluorides and for uranium tetrafluoride has shown that reduction of the double fluorides is possible. The exact experimental conditions for these reductions have been determined. Our study has shown in particular that the reduction of the double salt UF4, CaF2 by magnesium leads to the production of small (20 to 500 g) samples of high-purity uranium with a yield of 99 per cent. (author)
Review of modern double beta decay experiments
International Nuclear Information System (INIS)
The review of modern experiments on search and studying of double beta decay processes is done. Results of the most sensitive current experiments are discussed. The main attention is paid to EXO-200, KamLAND-Zen, GERDA-I and CUORE-0 experiments. Modern values of T1/2(2ν) and best present limits on neutrinoless double beta decay and double beta decay with Majoron emission are presented. Conservative limits on effective mass of a Majorana neutrino (〈mν〉 < 0.46 eV) and a coupling constant of Majoron to neutrino (〈gee〉 < 1.3 · 10−5) are obtained. Prospects of search for neutrinoless double beta decay in new experiments with sensitivity to 〈mν〉 at the level of ∼ 0.01-0.1 eV are discussed
Neutrino potential for neutrinoless double beta decay
Iwata, Yoritaka
2016-01-01
Neutrino potential for neutrinoless double beta decay is studied with focusing on its statistical property. The statistics provide a gross view of understanding amplitude of constitutional components of the nuclear matrix element.
Double field theory: a pedagogical review
Aldazabal, Gerardo; Marqués, Diego; Núñez, Carmen
2013-08-01
Double field theory (DFT) is a proposal to incorporate T-duality, a distinctive symmetry of string theory, as a symmetry of a field theory defined on a double configuration space. The aim of this review is to provide a pedagogical presentation of DFT and its applications. We first introduce some basic ideas on T-duality and supergravity in order to proceed to the construction of generalized diffeomorphisms and an invariant action on the double space. Steps towards the construction of a geometry on the double space are discussed. We then address generalized Scherk-Schwarz compactifications of DFT and their connection to gauged supergravity and flux compactifications. We also discuss U-duality extensions and present a brief parcours on worldsheet approaches to DFT. Finally, we provide a summary of other developments and applications that are not discussed in detail in the review.
Double Field Theory: A Pedagogical Review
Aldazabal, Gerardo; Nunez, Carmen
2013-01-01
Double Field Theory (DFT) is a proposal to incorporate T-duality, a distinctive symmetry of string theory, as a symmetry of a field theory defined on a double configuration space. The aim of this review is to provide a pedagogical presentation of DFT and its applications. We first introduce some basic ideas on T-duality and supergravity in order to proceed to the construction of generalized diffeomorphisms and an invariant action on the double space. Steps towards the construction of a geometry on the double space are discussed. We then address generalized Scherk-Schwarz compactifications of DFT and their connection to gauged supergravity and flux compactifications. We also discuss U-duality extensions, and present a brief parcours on world-sheet approaches to DFT. Finally, we provide a summary of other developments and applications that are not discussed in detail in the review.
UNVEILING THE PHENOMENON OF DOUBLE PERIODIC VARIABLES
Directory of Open Access Journals (Sweden)
R. E. Mennickent
2009-01-01
Full Text Available In this paper we give a brief report of our recent research on Double Periodic Variables (DPVs, including the discovery of DPVs in the Galaxy and some insights on the nature of their long-cycle variability.
The search for neutrinoless double beta decay
Gomez-Cadenas, J J; Mezzetto, M; Monrabal, F; Sorel, M
2011-01-01
In the last few years the search for neutrinoless double beta decay has evolved from being almost a marginal activity in neutrino physics to one of the highest priorities for understanding neutrinos and the origin of mass. There are two main reasons for this paradigm shift: the discovery of neutrino oscillations, which clearly established the existence of massive neutrinos; and the existence of an unconfirmed, but not refuted, claim of evidence for neutrinoless double decay in 76Ge. As a consequence, a new generation of experiments, employing different detection techniques and {\\beta}{\\beta} isotopes, is being actively promoted by experimental groups across the world. In addition, nuclear theorists are making remarkable progress in the calculation of the neutrinoless double beta decay nuclear matrix elements, thus eliminating a substantial part of the theoretical uncertainties affecting the particle physics interpretation of this process. In this report, we review the main aspects of the double beta decay pro...
Graph choosability and double list colorability
Hamid-Reza Fanaï
2010-01-01
In this paper, we give a sufficient condition for graph choosability, based on Combinatorial Nullstellensatz and a specific property, called "double list colorability", which means that there is a list assignment for which there are exactly two admissible colorings.
Frequency Doubling Broadband Light in Multiple Crystals
International Nuclear Information System (INIS)
The authors compare frequency doubling of broadband light in a single nonlinear crystal with doubling in five crystals with intercrystal temporal walk off compensation, and with doubling in five crystals adjusted for offset phase matching frequencies. Using a plane-wave, dispersive numerical model of frequency doubling they study the bandwidth of the second harmonic and the conversion efficiency as functions of crystal length and fundamental irradiance. For low irradiance the offset phase matching arrangement has lower efficiency than a single crystal of the same total length but gives a broader second harmonic bandwidth. The walk off compensated arrangement gives both higher conversion efficiency and broader bandwidth than a single crystal. At high irradiance, both multicrystal arrangements improve on the single crystal efficiency while maintaining broad bandwidth
Review of modern double beta decay experiments
Energy Technology Data Exchange (ETDEWEB)
Barabash, A. S., E-mail: barabash@itep.ru [Institute of Theoretical and Experimental Physics (NRC ”Kurchatov Institute”), B. Cheremushkinskaya 25, Moscow (Russian Federation)
2015-10-28
The review of modern experiments on search and studying of double beta decay processes is done. Results of the most sensitive current experiments are discussed. The main attention is paid to EXO-200, KamLAND-Zen, GERDA-I and CUORE-0 experiments. Modern values of T{sub 1/2}(2ν) and best present limits on neutrinoless double beta decay and double beta decay with Majoron emission are presented. Conservative limits on effective mass of a Majorana neutrino (〈m{sub ν}〉 < 0.46 eV) and a coupling constant of Majoron to neutrino (〈g{sub ee}〉 < 1.3 · 10{sup −5}) are obtained. Prospects of search for neutrinoless double beta decay in new experiments with sensitivity to 〈m{sub ν}〉 at the level of ∼ 0.01-0.1 eV are discussed.
Electron impact double ionization of Mg+ ions
International Nuclear Information System (INIS)
Electron impact ionization of atoms/ions is one of the fundamental atomic collision processes. Absolute cross sections for electron impact single and multiple ionization are of considerable importance in many fields like astrophysics and controlled nuclear fusion. Theoretical studies of electron impact double ionisation cross sections of Mg+ ions have been performed in the binary encounter approximation (BEA). Direct double ionisation has been investigated in the modified double binary encounter model. Ionization cross sections of different shells have been also calculated in order to analyse the contributions to double ionisation from ionisation-autoionization. The effect of the Coulombic field of the target ion on the incident electron has been considered in the present work. Accurate expression of σΔE (cross-section for energy transfer ΔE) and Hartree-Fock velocity distributions for the target electrons have been used throughout the calculations. The theoretical results show satisfactory agreement with the experimental observations. (authors)
Double field theory: a pedagogical review
International Nuclear Information System (INIS)
Double field theory (DFT) is a proposal to incorporate T-duality, a distinctive symmetry of string theory, as a symmetry of a field theory defined on a double configuration space. The aim of this review is to provide a pedagogical presentation of DFT and its applications. We first introduce some basic ideas on T-duality and supergravity in order to proceed to the construction of generalized diffeomorphisms and an invariant action on the double space. Steps towards the construction of a geometry on the double space are discussed. We then address generalized Scherk–Schwarz compactifications of DFT and their connection to gauged supergravity and flux compactifications. We also discuss U-duality extensions and present a brief parcours on worldsheet approaches to DFT. Finally, we provide a summary of other developments and applications that are not discussed in detail in the review. (topical review)
Clitic doubling and pure agreement person features
Directory of Open Access Journals (Sweden)
Ricardo Machado Rocha
2016-03-01
Full Text Available In this paper, we analyze clitic doubling constructions in dialectal non-standard Brazilian Portuguese. Within the Minimalism Framework, we explain very peculiar aspects of the doubled structures in this language, namely the fact that they occur only for 1st and 2nd person pronouns and that they co-vary with single clitic structures and single strong pronoun structures. Our approach assumes that the clitics me and te are hosted by a dedicated functional projection and result from the checking of the sole person feature [speaker:±]. Moreover, we show that, unlikely other cross-linguistic phenomena of pronominal doubling, Brazilian Portuguese Clitic Doubling does neither yield (nor is a result of any interpretive effect, but rather is an instance of a pure agreement chain. This leads us to advocate, contra the standard Minimalist Program, for the validity of the conceptual postulation of AgrP, as a condition on well-formedness of certain structures.
Propagator for the double delta potential
International Nuclear Information System (INIS)
The propagator for the double delta potential is calculated starting from the integral form of the Schroedinger equation. A compact expression of its Laplace transform is found, that can be explicitly inverted in some limiting cases
Wavelength-doubling optical parametric oscillator
Armstrong, Darrell J.; Smith, Arlee V.
2007-07-24
A wavelength-doubling optical parametric oscillator (OPO) comprising a type II nonlinear optical medium for generating a pair of degenerate waves at twice a pump wavelength and a plurality of mirrors for rotating the polarization of one wave by 90 degrees to produce a wavelength-doubled beam with an increased output energy by coupling both of the degenerate waves out of the OPO cavity through the same output coupler following polarization rotation of one of the degenerate waves.
Searches for neutrinoless double beta decay
Schwingenheuer, Bernhard
2012-07-01
Neutrinoless double beta decay is a lepton number violating process whose observation would also establish that neutrinos are their own anti-particles. There are many experimental efforts with a variety of techniques. Some (EXO, Kamland-Zen, GERDA phase I and CANDLES) started take data in 2011 and EXO has reported the first measurement of the half life for the double beta decay with two neutrinos of 136Xe. The sensitivities of the different proposals are reviewed.
Searches for neutrinoless double beta decay
Schwingenheuer, B
2012-01-01
Neutrinoless double beta decay is a lepton number violating process whose observation would also establish that neutrinos are their own anti-particles. There are many experimental efforts with a variety of techniques. Some (EXO, Kamland-Zen, GERDA phase I and CANDLES) started take data in 2011 and EXO has reported the first measurement of the half life for the double beta decay with two neutrinos of $^{136}$Xe. The sensitivities of the different proposals are reviewed.
Fuzzy Optimal Control for Double Inverted Pendulum
Al-Hadithi, Basil M.; Barragán Piña, Antonio Javier; Andujar Marquez, Jose Manuel; Jiménez Avello, Agustín
2012-01-01
In this paper a fuzzy optimal control for stabilizing an upright position a double inverted pendulum (DIP) is developed and compared. Modeling is based on Euler-Lagrange equations. This results in a complicated nonlinear fast reaction, unstable multivariable system. Firstly, the mathematical models of double pendulum system are presented. The weight variable fuzzy input is gained by combining the fuzzy control theory with the optimal control theory. Simulation results show that the controller...
Concordance of Bing Doubles and Boundary Genus
Livingston, Charles; van Cott, Cornelia A.
2011-11-01
Cha and Kim proved that if a knot K is not algebraically slice, then no iterated Bing double of K is concordant to the unlink. We prove that if K has nontrivial signature $\\sigma$, then the n-iterated Bing double of K is not concordant to any boundary link with boundary surfaces of genus less than $2^{n-1}\\sigma$. The same result holds with $\\sigma$ replaced by $2\\tau$, twice the Ozsvath-Szabo knot concordance invariant.
Mitigating Double Taxation in an Open Economy
Lindhe, Tobias
2001-01-01
The interaction of various methods of mitigating economic and international double taxation of corporate source income is studied within a standard neoclassical model of firm behavior. The main purpose is to determine to what extent methods effective in mitigating economic double taxation in a closed economy remain useful in an open economy where the firm's marginal investor is a foreigner. While a cut in the statutory corporate tax rate invariably reduces the cost of capital, the impact of t...
Double bank runs and liquidity risk management
Ippolito, Filippo; Peydr??, Jos??-Luis; Polo, Andrea; Sette, Enrico
2015-01-01
By providing liquidity to depositors and credit line borrowers, banks are exposed to double-runs on assets and liabilities. For identification, we exploit the 2007 freeze of the European interbank market and the Italian Credit Register. After the shock, there are sizeable, aggregate double-runs. In the cross-section, pre-shock interbank exposure is (unconditionally) unrelated to post-shock credit line drawdowns. However, conditioning on firm observable and unobservable characteristics, higher...
Double Soft Theorem for Perturbative Gravity
Saha, Arnab Priya
2016-01-01
Following up on the recent work of Cachazo, He and Yuan \\cite{arXiv:1503.04816 [hep-th]}, we derive the double soft graviton theorem in perturbative gravity. We show that the double soft theorem derived using CHY formula precisely matches with the perturbative computation involving Feynman diagrams. In particular, we find how certain delicate limits of Feynman diagrams play an important role in obtaining this equivalence.
Conserved currents of double field theory
Blair, Chris D. A.
2016-04-01
We find the conserved current associated to invariance under generalised diffeomorphisms in double field theory. This can be used to define a generalised Komar integral. We comment on its applications to solutions, in particular to the fundamental string/pp-wave. We also discuss the current in the context of Scherk-Schwarz compactifications. We calculate the current for both the original double field theory action, corresponding to the NSNS sector alone, and for the RR sector.
Double Entry in Accounting of Small Businesses
Gogol Tatyana A.
2013-01-01
The article states that a separate category of small businesses (starting from 2011) acquired the right to conduct simplified accounting of income and expenses without application of the plan of accounts and method of double entry. Analysis of literature sources allowed drawing a conclusion that it is impossible to imagine development of accounting without the use of the method of double entry and appearance of various theories regarding the reasons of its appearance. Having analysed methods ...
Double shell tank waste analysis plan
International Nuclear Information System (INIS)
Waste analysis plan for the double shell tanks. SD-WM-EV-053 is Superseding SD-WM-EV-057.This document provides the plan for obtaining information needed for the safe waste handling and storage of waste in the Double Shell Tank Systems. In Particular it addresses analysis necessary to manage waste according to Washington Administrative Code 173-303 and Title 40, parts 264 and 265 of the Code of Federal Regulations
Pouget, J.-P.; Ravanat, J.-L.; Douki, T.; Richard, M.-J.; Cadet, J.
1999-01-01
We used the comet assay associated with DNA-glycosylases to estimate DNA damage in cells exposed to gamma irradiation or photosensitized either with methylene blue or orange acridine. A calibration performed using irradiation allowed the measurement of the steady-state level and the yield of 8-oxodGuo as well as strand breaks and alkali-labile sites. Nous avons utilisé la méthode des comètes associée à des ADN-glycosylases, pour estimer les dommages de l'ADN dans des cellules après l'exposition à un rayonnement gamma ou après photosensibilisation par le bleu de méthylène ou l'acridine orange. Une calibration de la méthode des comètes a permis de mesurer le niveau basal et les taux de formation de 8-oxodGuo ainsi que le nombre de cassures de brins et de sites alcali labiles.
THE EFFICIENCY OF TENNIS DOUBLES SCORING SYSTEMS
Directory of Open Access Journals (Sweden)
Geoff Pollard
2010-09-01
Full Text Available In this paper a family of scoring systems for tennis doubles for testing the hypothesis that pair A is better than pair B versus the alternative hypothesis that pair B is better than A, is established. This family or benchmark of scoring systems can be used as a benchmark against which the efficiency of any doubles scoring system can be assessed. Thus, the formula for the efficiency of any doubles scoring system is derived. As in tennis singles, one scoring system based on the play-the-loser structure is shown to be more efficient than the benchmark systems. An expression for the relative efficiency of two doubles scoring systems is derived. Thus, the relative efficiency of the various scoring systems presently used in doubles can be assessed. The methods of this paper can be extended to a match between two teams of 2, 4, 8, …doubles pairs, so that it is possible to establish a measure for the relative efficiency of the various systems used for tennis contests between teams of players.
搜索改变整个世界——Google创始人之一Sergey Brin
Institute of Scientific and Technical Information of China (English)
吕娜
2009-01-01
Google的两个创始人中似乎产品总裁拉里·佩奇（Larry Page）的公开亮相更多些,更为大众所熟知,殊不知塞吉·布林（Sergey Brin）作为技术总裁,也成就了Google大规模分布式并行计算领域的创新,缔造了Google这电脑时代壮观的企业神话。
The Design and its Verification of the Double Rotor Double Cage Induction Motor
Sinha, Sumita; Deb, Nirmal K.; Biswas, Sujit K.
2016-06-01
The concept of a double rotor motor presented earlier and its equivalent circuit has been developed, showing a non-linear parameter content. The two rotors (which are recommended to be double cage type for development of high starting torque) can run with equal or unequal speed independently, depending on their individual loading. This paper presents the elaborate design procedure, step-by-step, for the double rotor double cage motor and verifies the designed data with that obtained from three separate tests (compared to two for conventional motor) on a prototype, such that optimum performance can be obtained from the motor.
Double-difference adjoint seismic tomography
Yuan, Yanhua O.; Simons, Frederik J.; Tromp, Jeroen
2016-06-01
We introduce a `double-difference' method for the inversion for seismic wavespeed structure based on adjoint tomography. Differences between seismic observations and model predictions at individual stations may arise from factors other than structural heterogeneity, such as errors in the assumed source-time function, inaccurate timings, and systematic uncertainties. To alleviate the corresponding nonuniqueness in the inverse problem, we construct differential measurements between stations, thereby reducing the influence of the source signature and systematic errors. We minimize the discrepancy between observations and simulations in terms of the differential measurements made on station pairs. We show how to implement the double-difference concept in adjoint tomography, both theoretically and in practice. We compare the sensitivities of absolute and differential measurements. The former provide absolute information on structure along the ray paths between stations and sources, whereas the latter explain relative (and thus higher-resolution) structural variations in areas close to the stations. Whereas in conventional tomography a measurement made on a single earthquake-station pair provides very limited structural information, in double-difference tomography one earthquake can actually resolve significant details of the structure. The double-difference methodology can be incorporated into the usual adjoint tomography workflow by simply pairing up all conventional measurements; the computational cost of the necessary adjoint simulations is largely unaffected. Rather than adding to the computational burden, the inversion of double-difference measurements merely modifies the construction of the adjoint sources for data assimilation.
Synthesis of layered double hydroxides from eggshells
Energy Technology Data Exchange (ETDEWEB)
Li Songnan [Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, 150001 (China); Wang Fangyong [College of Engineering and Technology, Northeast Forestry University, 150001 (China); Jing Xiaoyan [Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, 150001 (China); Wang Jun, E-mail: zhqw1888@sohu.com [Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, 150001 (China); Saba, Jamil; Liu Qi; Ge Lan; Song Dalei; Zhang Milin [Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, 150001 (China)
2012-01-16
Graphical abstract: This is the XRD pattern and TEM image of 4Ca-Al layered double hydroxide, which is obtained from eggshells. It can be seen that the sample is of layered double hydroxide and shows the plate-like agglomerations with an average size of 20-100 nm. Highlights: Black-Right-Pointing-Pointer We synthesize layered double hydroxides from eggshells. Black-Right-Pointing-Pointer Eggshells are the mainly material in this method. Black-Right-Pointing-Pointer The additional alkaline solution is not required. - Abstract: Ca-Al and Ca-Fe layered double hydroxides (LDHs) were successfully synthesized from chicken eggshells by an ultrasonic wave assistant method. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR) techniques. XRD and TEM analyses showed that the 4Ca-Al LDHs were of high purity but other samples were not. The present study provides a simple, efficient and environmental friendly method to obtain LDHs from biowaste eggshells, in which additional alkaline solution is not required for synthesis. Moreover, eggshells provide all the requisite bivalent metal ions, which are needed to form layered double hydroxides.
Observing and Measuring Visual Double Stars
2013-01-01
In these days of high-precision astrometric satellites, tremendous contributions to the science of astrometry are being made by amateur astronomers around the globe. This second edition of Observing and Measuring Visual Double Stars contains a significant amount of completely new material inspired by the work done by observers - particularly in the USA - since the first edition was published. Fifteen skilled and experienced astronomers have contributed chapters on their own specialization in the various fields. These include how to use the Internet to carry out precise astronomical measurement, an excellent guide to sketching double stars, and information on how to image double stars of unequal brightness. This new edition is the definitive book for those who are serious about this fascinating aspect of astronomy! Author Bob Argyle has been observing visual double stars for more than 40 years, some with the help of the world's biggest refractors, and has been director of the Webb Society Double Star Se...
Doubled strings, negative strings and null waves
Blair, Chris D A
2016-01-01
We revisit the fundamental string (F1) solution in the doubled formalism. We show that the wave-like solution of double field theory (DFT) corresponding to the F1/pp-wave duality pair is more properly a solution of the DFT action coupled to a doubled sigma model action. The doubled string configuration which sources the pp-wave can be thought of as static gauge with the string oriented in a dual direction. We also discuss the DFT solution corresponding to a vibrating string, carrying both winding and momentum. We further show that the solution dual to the F1 in both time and space can be viewed as a "negative string" solution. Negative branes are closely connected to certain exotic string theories which involve unusual signatures for both spacetime and brane worldvolumes. In order to better understand this from the doubled point of view, we construct a variant of DFT suitable for describing theories in which the fundamental string has a Euclidean worldsheet, for which T-dualities appear to change the spacetim...
Origin of double-line structure in nonsequential double ionization by few-cycle laser pulses
Huang, Cheng; Zhong, Mingmin; Wu, Zhengmao
2016-07-01
We investigate nonsequential double ionization (NSDI) of molecules by few-cycle laser pulses at the laser intensity of 1.2-1.5 × 1014 W/cm2 using the classical ensemble model. The same double-line structure as the lower intensity (1.0 × 1014 W/cm2) is also observed in the correlated electron momentum spectra for 1.2-1.4 × 1014 W/cm2. However, in contrast to the lower intensity where NSDI proceeds only through the recollision-induced double excitation with subsequent ionization (RDESI) mechanism, here, the recollision-induced excitation with subsequent ionization (RESI) mechanism has a more significant contribution to NSDI. This indicates that RDESI is not necessary for the formation of the double-line structure and RESI can give rise to the same type of structure independently. Furthermore, we explore the ultrafast dynamics underlying the formation of the double-line structure in RESI.
Double Planet Meets Triple Star
2002-08-01
High-Resolution VLT Image of Pluto Event on July 20, 2002 A rare celestial phenomenon involving the distant planet Pluto has occurred twice within the past month. Seen from the Earth, this planet moved in front of two different stars on July 20 and August 21, respectively, providing observers at various observatories in South America and in the Pacific area with a long awaited and most welcome opportunity to learn more about the tenuous atmosphere of that cold planet. On the first date, a series of very sharp images of a small sky field with Pluto and the star was obtained with the NAOS-CONICA (NACO) adaptive optics (AO) camera mounted on the ESO VLT 8.2-m YEPUN telescope at the Paranal Observatory. With a diameter of about 2300 km, Pluto is about six times smaller than the Earth. Like our own planet, it possesses a relatively large moon, Charon , measuring 1200 km across and circling Pluto at a distance of about 19,600 km once every 6.4 days. In fact, because of the similarity of the two bodies, the Pluto-Charon system is often referred to as a double planet . At the current distance of nearly 4,500 million km from the Earth, Pluto's disk subtends a very small angle in the sky, 0.107 arcsec. It is therefore very seldom that Pluto - during its orbital motion - passes exactly in front of a comparatively bright star. Such events are known as "occultations" , and it is difficult to predict exactly when and where on the Earth's surface they are visible. Stellar occultations When Pluto moves in front of a star, it casts a "shadow" on the Earth's surface within which an observer cannot see the star, much like the Earth's Moon hides the Sun during a total solar eclipse. During the occultation event, Pluto's "shadow" also moves across the Earth's surface. The width of this shadow is equal to Pluto's diameter, i.e. about 2300 km. One such occultation event was observed in 1988, and two others were expected to occur in 2002, according to predictions published in 2000 by
Chamber Structure of Double Hurwitz numbers
Cavalieri, Renzo; Markwig, Hannah
2010-01-01
Double Hurwitz numbers count covers of the projective line by genus g curves with assigned ramification profiles over 0 and infinity, and simple ramification over a fixed branch divisor. Goulden, Jackson and Vakil have shown double Hurwitz numbers are piecewise polynomial in the orders of ramification, and Shadrin, Shapiro and Vainshtein have determined the chamber structure and wall crossing formulas for g=0. This paper gives a unified approach to these results and strengthens them in several ways -- the most important being the extension of the results of Shapiro, Shadrin and Vainshtein to arbitrary genus. The main tool is the authors' previous work expressing double Hurwitz number as a sum over certain labeled graphs. We identify the labels of the graphs with lattice points in the chambers of certain hyperplane arrangements, which are well known to give rise to piecewise polynomial functions. Our understanding of the wall crossing for these functions builds on the work of Varchenko, and could have broader ...
Double hadron leptoproduction in the nuclear medium
Airapetian, A; Akopov, Z; Amarian, M; Andrus, A; Aschenauer, E C; Augustyniak, W; Avakian, R; Avetisian, A; Avetissian, E; Bailey, P; Belostotskii, S; Bianchi, N; Blok, H P; Böttcher, Helmut B; Borisov, A; Borysenko, A; Brüll, A; Bryzgalov, V; Capiluppi, M; Capitani, G P; Ciullo, G; Contalbrigo, M; Dalpiaz, P F; Deconinck, W; De Leo, R; Demey, M; De Nardo, L; De Sanctis, E; Devitsin, E G; Diefenthaler, M; Di Nezza, P; Dreschler, J; Düren, M; Ehrenfried, M; Elalaoui-Moulay, A; Elbakian, G; Ellinghaus, F; Elschenbroich, U; Fabbri, R; Fantoni, A; Felawka, L; Frullani, S; Funel, A; Gapienko, G; Gapienko, V; Garibaldi, F; Garrow, K; Gavrilov, G; Karibian, V; Giordano, F; Grebenyuk, O; Gregor, I M; Griffioen, K; Guler, H; Hadjidakis, C; Hartig, M; Hasch, D; Hasegawa, T; Hesselink, W H A; Hillenbrand, A; Hoek, M; Holler, Y; Hommez, B; Hristova, I; Iarygin, G; Ivanilov, A; Izotov, A; Jackson, H E; Jgoun, A; Kaiser, R; Keri, T; Kinney, E; Kiselev, A; Kobayashi, T; Kopytin, M; Korotkov, V; Kozlov, V; Krauss, B; Kravchenko, P; Krivokhizhin, V G; Lagamba, L; Lapikas, L; Lenisa, P; Liebing, P; Linden-Levy, L A; Lorenzon, W; Lü, J; Lu, S; Ma, B Q; Maiheu, B; Makins, N C R; Mao, Y; Marianski, B; Marukyan, H; Masoli, F; Mexner, V; Meyners, N; Michler, T; Miklukho, O; Miller, C A; Miyachi, Y; Muccifora, V; Murray, M; Nagaitsev, A; Nappi, E; Naryshkin, Yu; Negodaev, M; Nowak, Wolf-Dieter; Ohsuga, H; Osborne, A; Perez-Benito, R; Pickert, N; Raithel, M; Reggiani, D; Reimer, P E; Reischl, A; Reolon, A R; Riedl, C; Rith, K; Rosner, G; Rostomyan, A; Rubacek, L; Rubin, J; Ryckbosch, D; Salomatin, Y; Sanjiev, I; Savin, I; Schäfer, A; Schnell, G; Schüler, K P; Seele, J; Seidl, R; Seitz, B; Shearer, C; Shibata, T A; Shutov, V; Sinram, K; Stancari, M; Statera, M; Steffens, E; Steijger, J J M; Stenzel, H; Stewart, J; Stinzing, F; Streit, J; Tait, P; Tanaka, H; Taroian, S P; Tchuiko, B; Terkulov, A R; Trzcinski, A; Tytgat, M; Vandenbroucke, A; Van der Nat, P B; van der Steenhoven, G; Van Haarlem, Y; Veretennikov, D; Vikhrov, V; Vogel, C; Wang, S; Ye, Y; Ye, Z; Yen, S; Zihlmann, B; Zupranski, P
2006-01-01
First measurement of double-hadron production in deep-inelastic scattering has been measured with the HERMES spectrometer at HERA using a 27.6 GeV positron beam with deuterium, nitrogen, krypton and xenon targets. The influence of the nuclear medium on the ratio of double-hadron to single-hadron yields has been investigated. Nuclear effects are clearly observed but with substantially smaller magnitude and reduced $A$-dependence compared to previously measured single-hadron multiplicity ratios. The data are in fair agreement with models based on partonic or pre-hadronic energy loss, while they seem to rule out a pure absorptive treatment of the final state interactions. Thus, the double-hadron ratio provides an additional tool for studying modifications of hadronization in nuclear matter.
Doubling Strong Lensing as a Cosmological Probe
Linder, Eric V
2016-01-01
Strong gravitational lensing provides a geometric probe of cosmology in a unique manner through distance ratios involving the source and lens. This is well known for the time delay distance derived from measured delays between lightcurves of the images of variable sources such as quasars. Recently, double source plane lens systems involving two constant sources lensed by the same foreground lens have been proposed as another probe, involving a different ratio of distances measured from the image positions and fairly insensitive to the lens modeling. Here we demonstrate that these two different sets of strong lensing distance ratios have strong complementarity in cosmological leverage. Unlike other probes, the double source distance ratio is actually more sensitive to the dark energy equation of state parameters $w_0$ and $w_a$ than to the matter density $\\Omega_m$, for low redshift lenses. Adding double source distance ratio measurements can improve the dark energy figure of merit by 40% for a sample of fewer...
Neutrinoless double beta decay from lattice QCD
Nicholson, Amy; Chang, Chia Cheng; Clark, M A; Joo, Balint; Kurth, Thorsten; Rinaldi, Enrico; Tiburzi, Brian; Vranas, Pavlos; Walker-Loud, Andre
2016-01-01
While the discovery of non-zero neutrino masses is one of the most important accomplishments by physicists in the past century, it is still unknown how and in what form these masses arise. Lepton number-violating neutrinoless double beta decay is a natural consequence of Majorana neutrinos and many BSM theories, and many experimental efforts are involved in the search for these processes. Understanding how neutrinoless double beta decay would manifest in nuclear environments is key for understanding any observed signals. In these proceedings we present an overview of a set of one- and two-body matrix elements relevant for experimental searches for neutrinoless double beta decay, describe the role of lattice QCD calculations, and present preliminary lattice QCD results.
Double-Spinor Superstrings on Coset Superspaces
Kunitomo, Hiroshi
2008-01-01
The double-spinor formalism, proposed by Aisaka and Kazama, provides a basis for the pure-spinor formalism, which allows manifestly super-Poincare covariant quantization of superstrings. We extend it to the case of backgrounds realized by coset superspaces. A general method constructing reparametrization invariant action is given by using two concrete examples, the flat space-time and AdS(5)xS(5). We find that it is natural to double not only the spinor coordinates but the whole superspace for describing double-spinor superstrings on such backgrounds. The reparametrization invariant action has local symmetries compensating those extra degrees of freedom, which guarantee the equivalence to the Green-Schwarz formalism.
Perturbative Double Field Theory on General Backgrounds
Hohm, Olaf
2015-01-01
We develop the perturbation theory of double field theory around arbitrary solutions of its field equations. The exact gauge transformations are written in a manifestly background covariant way and contain at most quadratic terms in the field fluctuations. We expand the generalized curvature scalar to cubic order in fluctuations and thereby determine the cubic action in a manifestly background covariant form. As a first application we specialize this theory to group manifold backgrounds, such as $SU(2) \\simeq S^3$ with $H$-flux. In the full string theory this corresponds to a WZW background CFT. Starting from closed string field theory, the cubic action around such backgrounds has been computed before by Blumenhagen, Hassler and L\\"ust. We establish precise agreement with the cubic action derived from double field theory. This result confirms that double field theory is applicable to arbitrary curved background solutions, disproving assertions in the literature to the contrary.
Precision muon reconstruction in Double Chooz
International Nuclear Information System (INIS)
We describe a muon track reconstruction algorithm for the reactor anti-neutrino experiment Double Chooz. The Double Chooz detector consists of two optically isolated volumes of the liquid scintillator viewed by PMTs, and an Outer Veto above these made of crossed scintillator strips. Muons are reconstructed by their Outer Veto hit positions along with timing information from the other two detector volumes. All muons are fit under the hypothesis that they are through-going and ultrarelativistic. If the energy depositions suggest that the muon may have stopped, the reconstruction fits also for this hypothesis and chooses between the two via the relative goodness-of-fit. In the ideal case of a through-going muon intersecting the center of the detector, the resolution is ∼40mm in each transverse dimension. High quality muon reconstruction is an important tool for reducing the impact of the cosmogenic isotope background in Double Chooz
Explaining the Double-Slit Experiment
Directory of Open Access Journals (Sweden)
Moshe Wallace Callen
2011-01-01
Full Text Available In response to Orion and Laitman’s [1] explanation of the classic double-slit experiment of quantum mechanics, we propose an alternate explanation of that experiment by treating physical degrees of freedom as a conserved physical quantity, instead of referring to “vague terms” used in previous explanations, [1], that are not broadly applicable. Explanation in [1] refers to properties of groups of particles, even though the double-slit experiment’s results should address only to a single particle. By using physical degrees of freedom and the application of Hamilton’s principle, we obtain a single particle explanation of the double-slit experiment in terms of properties and via methods which apply equally in a quantum and a classical regime.
Can acupuncture treatment be double-blinded?
DEFF Research Database (Denmark)
Vase, Lene; Baram, Sara; Takakura, Nobuari;
2015-01-01
acupuncturists were asked about perceived treatment allocation at the end of the study. To test if there were clues which led to identification of the treatment, deep dull pain associated with needle application and rotation (termed "de qi" in East Asian medicine), and patients' pain levels were assessed......Blinding protects against bias but the success of blinding is seldom assessed and reported in clinical trials including studies of acupuncture where blinding represents a major challenge. Recently, needles with the potential for double-blinding were developed, so we tested if acupuncture can be...... double-blinded in a randomized study of sixty-seven patients with acute pain ≥ 3 (0-10 scale following third molar removal) who received active acupuncture with a penetrating needle or placebo acupuncture with a non-penetrating needle. To test if acupuncture was administered double-blind, patients and...
Close Double Stars from Occultation Video Recordings
Waring Dunham, David; George, Anthony; Loader, Brian; Herald, David Russell
2015-08-01
Astronomers around the world, both amateur and professional, have been recording lunar and asteroidal occultations of close double stars during the past several years using inexpensive but quite sensitive video cameras that are now available. Several new double stars have been discovered, and the parameters of many close systems have been determined. Besides rather good measurements of the relative magnitudes of the components, the actual separations and position angles can be measured if observations of the same event are made from two or more separate stations. These observations collected by the International Occultation Timing Association (IOTA) are published in the Journal of Double Star Observations. Recently, IOTA has encouraged the observation of occultations of stars in the Kepler 2 program, which is interested in data about close duplicity that affects their analyses for exoplanet transits.
Luminescence upconversion in colloidal double quantum dots.
Deutsch, Zvicka; Neeman, Lior; Oron, Dan
2013-09-01
Luminescence upconversion nanocrystals capable of converting two low-energy photons into a single photon at a higher energy are sought-after for a variety of applications, including bioimaging and photovoltaic light harvesting. Currently available systems, based on rare-earth-doped dielectrics, are limited in both tunability and absorption cross-section. Here we present colloidal double quantum dots as an alternative nanocrystalline upconversion system, combining the stability of an inorganic crystalline structure with the spectral tunability afforded by quantum confinement. By tailoring its composition and morphology, we form a semiconducting nanostructure in which excited electrons are delocalized over the entire structure, but a double potential well is formed for holes. Upconversion occurs by excitation of an electron in the lower energy transition, followed by intraband absorption of the hole, allowing it to cross the barrier to a higher energy state. An overall conversion efficiency of 0.1% per double excitation event is achieved. PMID:23912060
Search for resonant double-electron capture
Energy Technology Data Exchange (ETDEWEB)
Eliseev, Sergey; Blaum, Klaus; Roux, Christian [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Block, Michael; Minaya Ramirez, Enrique [GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Darmstadt (Germany); Droese, Christian; Schweikhard, Lutz [Institut fuer Physik, Ernst-Moritz-Arndt-Universitaet, Greifswald (Germany); Nesterenko, Dmitriy; Novikov, Yuri [PNPI, St. Petersburg (Russian Federation); Zuber, Kai [Institut fuer Kern- und Teilchenphysik, Technische Universitaet, Dresden (Germany)
2013-07-01
It is still unknown whether neutrinos are Dirac or Majorana particles. An answer to this question can be obtained from neutrinoless double-electron capture. An observation of this process would prove that the neutrino is a Majorana particle. A measurement of the half-life of this process would allow a determination of the effective Majorana neutrino mass. In the search for the nuclide with the largest probability for neutrinoless double-electron capture, we have determined the Q-values of several potentially suitable nuclides with SHIPTRAP by Penning-trap mass-ratio measurements. The ECEC-transition in {sup 152}Gd has been determined to have the smallest half-life of 10{sup 26} years for a 1 eV neutrino mass among all known 0νECEC-transitions, which makes {sup 152}Gd the most promising candidate for the search for neutrino-less double electron capture. This contribution summarizes the recent experimental results.
Double contrast CT diagnosis of shoulder instability
International Nuclear Information System (INIS)
Purpose: To study clinical importance of double contrast CT arthrography in the diagnosis of shoulder instability. Materials and methods: Eight patients were diagnosed as having shoulder instability with double contrast CT. The technique involved injection of 4 ml, 76% urografin and 10 ml of room air through an anterior shoulder puncture. The CT images were obtained with the patients supine and prone position. Results: The results of the CT arthrography were confirmed during the surgical operation afterward. The characteristics of abnormal double contrast CT arthrograms. They included anterior labral tear: the rounded anterior glenoid labrum, detached anterior labrum and anterior labral fragment; anterior capsular stripping off the anterior scapular glenoid neck; and enlargement of anterior and posterior capsular stripping off the anterior scapular glenoid neck; and enlargement of anterior and posterior capsular cavity. Conclusion: The current CT arthrography provides important X-ray information for both diagnosis of shoulder instability and anatomical repair of shoulder instability
Fluid dynamics of double diffusive systems
Energy Technology Data Exchange (ETDEWEB)
Koseff, J.R.
1988-05-01
A study of mixing processes in doubly diffusive systems is being conducted. Continuous gradients of two diffusing components (heat and salinity) are being used as initial conditions, and forcing is introduced by lateral heating, surface shear and sloping boundaries. The goals of the proposed work include: quantification of the effects of finite amplitude disturbances on stable, double diffusive systems, particularly with respect to lateral heating, development of an improved understanding of the physical phenomena present in wind-driven shear flows in double diffusive stratified environments, increasing our knowledge-base on turbulent flow in stratified environments and how to represent it, and formulation of numerical code for such flows. The work is being carried out in a new experimental facility at Stanford and on laboratory minicomputers and CRAY computers. In particular we are focusing on the following key issues. The formation and propagation of double diffusive intrusions away from a heated wall and the effects of lateral heating on the double diffusive system; The interaction between the double diffusively influenced fluxes and the turbulence induced fluxes; The formation of gravitational intrusions; and The influence of double diffusive gradients on mixed layer deepening. The goals of the project were as follows. Physical experiments: Construct experimental facility; Modify and fabricate instrument rakes; Develop sampling and calibration software; Develop stratification techniques; Conduct flow visualization studies; Qualify wind tunnel over a range of wind speeds. Numerical experiments: Adapt REMIXCS to handle turbulent flows; Investigate approaches for specifying wind field; Perform calculations for low wind speeds. With the exception of the wind tunnel qualification, all the tasks have already been completed and we are now conducting quantitative experiments. 2 figs.
Double-beta decay in gauge theories
International Nuclear Information System (INIS)
The double-beta decay in gauge theories is considered. The review of the 76Ge, 82Se, 96Zr, 100Cd, 128Te, 130Te, 136Xe and 150Nd experimental nuclear targets is presented. The mechanism of the Majorana intermediate neutrino is considered. The R-parity of the violation of the contribution to the 0νββ decay is studied. The effective nucleon currents in dependence on the momentum are discussed. The extraction of the lepton number, violating the double-β decay parameters is presented
Double-beta decay in deformed nuclei
International Nuclear Information System (INIS)
A brief review of theoretical results for the double-beta decay and the double-electron capture in heavy deformed nuclei is presented. The ββ half life of 160Gd is evaluated using an extended version of the pseudo SU(3) model. While the 2ν mode is forbidden when the most probable occupations are considered, states with different occupation numbers can be mixed through the pairing interaction. The amount of this mixing is calculated using perturbation theory. The possibility of observing the ββ decay in 160Gd is discussed for both the 2ν and 0ν modes. (author)
Kidd, Mary
2007-10-01
Studying double-beta decay at Triangle Universities Nuclear Laboratory (TUNL) is perhaps one of the most promising ways to pinpoint the neutrino mass. What they do not mention is that to study double-beta decay, you probably have to become a certified miner, and if you have a fear of goats, you should stay away. In this talk, I will tell you some of my experiences as a TUNL graduate student, and how I am now nearly qualified for a job in the mining industry.
Supervision of double extensive air showers
International Nuclear Information System (INIS)
Double extensive air showers were investigated at Tien-Shan high mountain scientific station of P.N. Lebedev Institute by means of two various installations. One installation registered electron-photon air shower component, another – Vavilov-Cherenkov radiation. On both installations the double showers divided by a time interval of ∼100 nanoseconds have been registered. In the present work frequency of occurrence of such showers in each of installations is analysed, and is shown that at supervision of vertical showers (zenith angle θ <60°) these frequencies coincide.
Simulations of Double White Dwarf Mergers
Motl, Patick; Staff, Jan; Marcello, Dominic; Clayton, Geoffrey; Frank, Juhan
2016-03-01
We present numerical simulations of double white dwarf mergers initiated by mass transfer instability. In particular, we are interested in the possible connection between such double degenerate mergers and the peculiar irregular variable R Corona Borealis stars. For the merger of a Carbon-Oxygen white dwarf with a Helium white dwarf, the degree to which Carbon from the accreting star is dredged up plays a crucial role in the appearance of the rejuvenated, merged object. We explore the amount of dredge up in the accreting star and its influence in stellar evolution models initialized from the merged object resulting from dynamical evolutions.
Superballistic wavepacket spreading in double kicked rotors
Fang, Ping; Wang, Jiao
2016-08-01
We investigate possible ways in which a quantum wavepacket spreads. We show that in a general class of double kicked rotor system, a wavepacket may undergo superballistic spreading; i.e., its variance increases as the cubic of time. The conditions for the observed superballistic spreading and two related characteristic time scales are studied. Our results suggest that the symmetry of the studied model and whether it is a Kolmogorov-Arnold-Moser system are crucial to its wavepacket spreading behavior. Our study also sheds new light on the exponential wavepacket spreading phenomenon previously observed in the double kicked rotor system.
Higher Spin Double Field Theory : A Proposal
Bekaert, Xavier
2016-01-01
We construct a double field theory of higher spin gravity. Employing "semi-covariant" differential geometry, we spell a functional in which each term is completely covariant with respect to $\\mathbf{O}(4,4)$ T-duality, doubled diffeomorphisms, $\\mathbf{Spin}(1,3)$ local Lorentz symmetry and, separately, $\\mathbf{HS}(4)$ higher spin gauge symmetry. We also propose a set of BPS-like conditions whose solutions automatically satisfy the full Euler-Lagrange equations. As such a solution, we derive a linear dilaton vacuum. With extra algebraic constraints further imposed, our BPS proposal reduces to the bosonic Vasiliev equations.
Double Harmonic Transmission (D.H.T.
Directory of Open Access Journals (Sweden)
Sava Ianici
2006-10-01
Full Text Available The paper presents the construction and functioning of a new type of harmonic drive named double harmonic transmission (D.H.T.. In the second part of this paper is presented the dynamic analysis of the double harmonic transmission, which is based on the results of the experimental researches on the D.H.T. This study of the stress status and the forces distribution is necessary for to determine the durability on the portant elements of the D.H.T.
Higher spin double field theory: a proposal
Bekaert, Xavier; Park, Jeong-Hyuck
2016-07-01
We construct a double field theory coupled to the fields present in Vasiliev's equations. Employing the "semi-covariant" differential geometry, we spell a functional in which each term is completely covariant with respect to O(4, 4) T-duality, doubled diffeomorphisms, Spin(1, 3) local Lorentz symmetry and, separately, HS(4) higher spin gauge symmetry. We identify a minimal set of BPS-like conditions whose solutions automatically satisfy the full Euler-Lagrange equations. As such a solution, we derive a linear dilaton vacuum. With extra algebraic constraints further supplemented, the BPS-like conditions reduce to the bosonic Vasiliev equations.
Double-Stranded Peptide Nucleic Acids
DEFF Research Database (Denmark)
2001-01-01
A novel class of compounds, known as peptide nucleic acids, form double-stranded structures with one another and with ssDNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker.......A novel class of compounds, known as peptide nucleic acids, form double-stranded structures with one another and with ssDNA. The peptide nucleic acids generally comprise ligands such as naturally occurring DNA bases attached to a peptide backbone through a suitable linker....
Explaining the Double-Slit Experiment
Moshe Wallace Callen; Shaul Sorek
2011-01-01
In response to Orion and Laitman’s [1] explanation of the classic double-slit experiment of quantum mechanics, we propose an alternate explanation of that experiment by treating physical degrees of freedom as a conserved physical quantity, instead of referring to “vague terms” used in previous explanations, [1], that are not broadly applicable. Explanation in [1] refers to properties of groups of particles, even though the double-slit experiment’s results should address only to a single parti...
Walborn, S. P.; Cunha, M. O. Terra; Padua, S.; Monken, C. H.
2001-01-01
We report a quantum eraser experiment which actually uses a Young double-slit to create interference. The experiment can be considered an optical analogy of an experiment proposed by Scully, Englert and Walther. One photon of an entangled pair is incident on a Young double-slit of appropriate dimensions to create an interference pattern in a distant detection region. Quarter-wave plates, oriented so that their fast axes are orthogonal, are placed in front of each slit to serve as which-path m...
Double-partition Quantum Cluster Algebras
DEFF Research Database (Denmark)
Jakobsen, Hans Plesner; Zhang, Hechun
2012-01-01
A family of quantum cluster algebras is introduced and studied. In general, these algebras are new, but sub-classes have been studied previously by other authors. The algebras are indexed by double parti- tions or double flag varieties. Equivalently, they are indexed by broken lines L. By grouping...... together neighboring mutations into quantum line mutations we can mutate from the cluster algebra of one broken line to another. Compatible pairs can be written down. The algebras are equal to their upper cluster algebras. The variables of the quantum seeds are given by elements of the dual canonical basis....
Quintessence Model With Double Exponential Potential
Sen, A A
2002-01-01
We have reinvestigated the quintessence model with minimally coupled scalar field in the context of recent Supernova observation at $z=1.7$. By assuming the form of the scale factor which gives both the early time deceleration and late time acceleration, consistent with the observations, we show that one needs a double exponential potential. We have also shown that the equation of state and the behaviour of dark energy density are reasonably consistent with earlier constraints obtained by different authors. This work shows again the importance of double exponential potential for a quintessence field.
Why search for double beta decay?
International Nuclear Information System (INIS)
Searching for neutrinoless double beta decay is the only known practical method for trying to determine whether neutrinos are their own antiparticles. The theoretical motivation for supposing that they may indeed be their own antiparticles is described. The reason that it is so difficult to ascertain experimentally whether they are or are not is explained, as is the special sensitivity of neutrinoless double beta decay. The potential implications of the observation of this reaction for neutrino mass and for the physics of neutrinos is discussed
Probing Angular Correlations in Sequential Double Ionization
International Nuclear Information System (INIS)
We study electron correlation in sequential double ionization of noble gas atoms and HCl in intense, femtosecond laser pulses. We measure the photoelectron angular distributions of Ne+ relative to the first electron in a pump-probe experiment with 8 fs, 800 nm, circularly polarized laser pulses at a peak intensity of a few 1015 W/cm2. Using a linear-linear pump-probe setup, we further study He, Ar, and HCl. We find a clear angular correlation between the two ionization steps in the sequential double ionization intensity regime.
Simulation Results of Double Forward Converter
Directory of Open Access Journals (Sweden)
P. Vijaya KUMAR
2009-12-01
Full Text Available This work aims to find a better forward converter for DC to DC conversion.Simulation of double forward converter in SMPS system is discussed in this paper. Aforward converter with RCD snubber to synchronous rectifier and/or to current doubleris also discussed. The evolution of the forward converter is first reviewed in a tutorialfashion. Performance parameters are discussed including operating principle, voltageconversion ratio, efficiency, device stress, small-signal dynamics, noise and EMI. Itscircuit operation and its performance characteristics of the forward converter with RCDsnubber and double forward converter are described and the simulation results arepresented.
On the trail of double peak hydrographs
Martínez-Carreras, Núria; Hissler, Christophe; Gourdol, Laurent; Klaus, Julian; Juilleret, Jérôme; François Iffly, Jean; McDonnell, Jeffrey J.; Pfister, Laurent
2016-04-01
A double peak hydrograph features two peaks as a response to a unique rainfall pulse. The first peak occurs at the same time or shortly after the precipitation has started and it corresponds to a fast catchment response to precipitation. The delayed peak normally starts during the recession of the first peak, when the precipitation has already ceased. Double peak hydrographs may occur for various reasons. They can occur (i) in large catchments when lag times in tributary responses are large, (ii) in urban catchments where the first peak is often caused by direct surface runoff on impervious land cover, and the delayed peak to slower subsurface flow, and (iii) in non-urban catchments, where the first and the delayed discharge peaks are explained by different runoff mechanisms (e.g. overland flow, subsurface flow and/or deep groundwater flow) that have different response times. Here we focus on the third case, as a formal description of the different hydrological mechanisms explaining these complex hydrological dynamics across catchments with diverse physiographic characteristics is still needed. Based on a review of studies documenting double peak events we have established a formal classification of catchments presenting double peak events based on their regolith structure (geological substratum and/or its weathered products). We describe the different hydrological mechanisms that trigger these complex hydrological dynamics across each catchment type. We then use hydrometric time series of precipitation, runoff, soil moisture and groundwater levels collected in the Weierbach (0.46 km2) headwater catchment (Luxembourg) to better understand double peak hydrograph generation. Specifically, we aim to find out (1) if the generation of a double peak hydrograph is a threshold process, (2) if the hysteretic relationships between storage and discharge are consistent during single and double peak hydrographs, and (3) if different functional landscape units (the hillslopes
Light shift manipulation and suppression in a double pass optical-magnetic double resonance system
International Nuclear Information System (INIS)
A double pass optical-magnetic double resonance system is proposed and applied for observing and manipulating the light shift in metastable 4He. By adjusting the degree of overlap in space between the incident and retro-reflected laser beams, the manipulation on light shift is realized and a flat range for light shift insensitive to optical frequency detuning can be formed. A simple hole-burning model based on velocity-selective optical pumping, including the velocity diffusion effect caused by velocity-changing collisions, is adopted to qualitatively clarify the light shift observed in the double pass system. (paper)
Double-isotope thyroid functional test
International Nuclear Information System (INIS)
In the radioimmunoassay one or two of the thyroid components T4, T3, TSH and TBG are labelled with 75Se and/or 125I. (For the labelled derivates many examples are given.) For measuring the concentration of the bound fractions a double-channel counter is used. (DG)
Double-shell tank emergency pumping guide
International Nuclear Information System (INIS)
This Double-Shell Tank Emergency Pumping Guide provides the preplanning necessary to expeditiously remove any waste that may leak from the primary tank to the secondary tank for Hanfords 28 DSTs. The strategy is described, applicable emergency procedures are referenced, and transfer routes and pumping equipment for each tank are identified
Double Jeopardy and University Students in Wisconsin.
Witmer, David R.
This document addresses the question of students being put into a position of double jeopardy--if they commit a civil offense, they are subject not only to trial by the public courts but are also subject to punishment by their educational institution. As a general rule, colleges and universities should not prosecute students for acts subject to…
The invertible double of elliptic operators
DEFF Research Database (Denmark)
Booss-Bavnbek, Bernhelm; Lesch, Matthias; Zhu, Chaofeng
We construct a canonical invertible double for general first order elliptic differential operators over smooth compact manifolds with boundary and derive a natural formula for the Calderon projector which yields a generalization of the famous Cobordism Theorem. Assuming symmetric principal symbol...
An Optimal Double Inequality for Means
Directory of Open Access Journals (Sweden)
Qian Wei-Mao
2010-01-01
Full Text Available For , the generalized logarithmic mean , arithmetic mean and geometric mean of two positive numbers and are defined by , ; , , , ; , , ; , , ; and , respectively. In this paper, we give an answer to the open problem: for , what are the greatest value and the least value , such that the double inequality holds for all ?
Double Δ production on the deuteron
International Nuclear Information System (INIS)
The γd → Δ++Δ- reaction which requires the collaboration of the two nucleons in the deuteron is studied. By means of a model developed for the γp → pπ+π- reaction, the two body exchange currents leading to double delta creation are derived. A fair agreement is obtained with a recent experiment
Stationary Double Layers in a Collisionless Magnetoplasma
DEFF Research Database (Denmark)
Noriyoshi, Sato; Mieno, Tetsu; Hatakeyama, Rikizo;
1983-01-01
plate on the low-potential side, being accompanied with current limitation. This localized potential drop moves along the plasma column, but finally stops and results in the formation of the stationary double layer in the presence of sufficient plasma supply from the plate on the high-potential side....
Double droplets simultaneous impact on liquid film
Guo, Y.; Chen, G.; Shen, S.; Zhang, J.
2015-09-01
The evolution of double droplets simultaneously impinging on flat liquid film are obtained with CLSVOF method(Combined Level Set and VOF). the impinging velocity, liquid film thickness, and the horizontal distance between the two droplets were investigated to analyze the factors that affect the evolution.
A double grid position sensitive avalanche chamber
International Nuclear Information System (INIS)
A double grid position sensitive avalanche chamber (DGAC) has been developed. Its sensitive area is 250 x 200 mm2. The properties of the DGAC were tested in flowing isobutylene gas at a pressure of 360 Pa. The position resolution of 4 mm in both x and y coordinates and the time resolution of 290 ps are obtained for 252Cf fission fragment source
International Nuclear Information System (INIS)
Coinciding with celebrations for the nation's 25th anniversary, the 25th International Conference on High Energy Physics, held in Singapore from 2-8 August, was itself a double festival, with the Standard Model of contemporary physics and CERN's new LEP electron-positron collider providing the twin themes
Relay Feedback Analysis for Double Integral Plants
Directory of Open Access Journals (Sweden)
Zhen Ye
2011-01-01
Full Text Available Double integral plants under relay feedback are studied. Complete results on the uniqueness of solutions, existence, and stability of the limit cycles are established using the point transformation method. Analytical expressions are also given for determining the amplitude and period of a limit cycle from the plant parameters.
On the double adiabatic continuous spectrum
International Nuclear Information System (INIS)
In earlier work it has been found that the Alfven and cusp (or slow) continuous spectra can become unstable in toroidal geometry, as judged from the linearized double adiabatic equations. In this paper the validity of fluid approaches to the present problem is investigated. The physical implications of the stability conditions are discussed. (Author)
Double tracks test site characterization report
International Nuclear Information System (INIS)
This report presents the results of site characterization activities performed at the Double Tracks Test Site, located on Range 71 North, of the Nellis Air Force Range (NAFR) in southern Nevada. Site characterization activities included reviewing historical data from the Double Tracks experiment, previous site investigation efforts, and recent site characterization data. The most recent site characterization activities were conducted in support of an interim corrective action to remediate the Double Tracks Test Site to an acceptable risk to human health and the environment. Site characterization was performed using a phased approach. First, previously collected data and historical records sere compiled and reviewed. Generalized scopes of work were then prepared to fill known data gaps. Field activities were conducted and the collected data were then reviewed to determine whether data gaps were filled and whether other areas needed to be investigated. Additional field efforts were then conducted, as required, to adequately characterize the site. Characterization of the Double Tracks Test Site was conducted in accordance with the US Department of Energy's (DOE) Streamlined Approach for Environmental Restoration (SAFER)
Semiconductor detectors and double beta decay
International Nuclear Information System (INIS)
The underlying theory of double beta decay is discussed as well as some experimental observations. A class of second generation 76Ge detector experiments is then discussed. The design and physics considerations involved in the system used by LBL are explained, particularly the means of rejecting background activity. 24 references, 18 figures, 3 tables
The Double Bind: The next Generation
Malcom, Lindsey E.; Malcom, Shirley M.
2011-01-01
In this foreword, Shirley Malcom and Lindsey Malcom speak to the history and current status of women of color in science, technology, engineering, and mathematics (STEM) fields. As the author of the seminal report "The Double Bind: The Price of Being a Minority Woman in Science", Shirley Malcom is uniquely poised to give us an insightful…
Double Acceptor Interaction in Semimagnetic Quantum Dot
Directory of Open Access Journals (Sweden)
A. Merwyn Jasper D. Reuben
2011-01-01
Full Text Available The effect of geometry of the semimagnetic Quantum Dot on the Interaction energy of a double acceptor is computed in the effective mass approximation using the variational principle. A peak is observed at the lower dot sizes as a magnetic field is increased which is attributed to the reduction in confinement.
LHC dijet constraints on double beta decay
Helo, J C
2015-01-01
We use LHC dijet data to derive constraints on neutrinoless double beta decay. Upper limits on cross sections for the production of "exotic" resonances, such as a right-handed W boson or a diquark, can be converted into lower limits on the double beta decay half-life for fixed choices of other parameters. Constraints derived from run-I data are already surprisingly strong and complementary to results from searches using same-sign dileptons plus jets. For the case of the left-right symmetric model, in case no new resonance is found in future runs of the LHC and assuming $g_L=g_R$, we estimate a lower limit on the double beta decay half-live larger than $10^{27}$ ys can be derived from future dijet data, except in the window of relatively light right-handed neutrino masses in the range $0.5$ MeV to $50$ GeV. Part of this mass window will be tested in the upcoming SHiP experiment. We also discuss current and future limits on possible scalar diquark contributions to double beta decay that can be derived from dije...
Comment on 'Biphoton double-slit experiment'
International Nuclear Information System (INIS)
In a recent paper [Phys. Rev. A 68, 033803 (2003)] experimental results on a double-slit configuration with two entangled bosons are presented. The authors argue that their data contradicts the de Broglie-Bohm interpretation of quantum mechanics. In this Comment we show that this conclusion is incorrect
How "Blind" Are Double-Blind Studies?
Margraf, Jurgen; And Others
1991-01-01
Compared alprazolam, imipramine, and placebo in the treatment of panic disorder patients (n=59) to investigate concerns about the internal validity of the double-blind design. Found that the great majority of patients and physicians were able to rate accurately whether active drug or placebo had been given and physicians could distinguish between…
Double tracks test site characterization report
Energy Technology Data Exchange (ETDEWEB)
NONE
1996-05-01
This report presents the results of site characterization activities performed at the Double Tracks Test Site, located on Range 71 North, of the Nellis Air Force Range (NAFR) in southern Nevada. Site characterization activities included reviewing historical data from the Double Tracks experiment, previous site investigation efforts, and recent site characterization data. The most recent site characterization activities were conducted in support of an interim corrective action to remediate the Double Tracks Test Site to an acceptable risk to human health and the environment. Site characterization was performed using a phased approach. First, previously collected data and historical records sere compiled and reviewed. Generalized scopes of work were then prepared to fill known data gaps. Field activities were conducted and the collected data were then reviewed to determine whether data gaps were filled and whether other areas needed to be investigated. Additional field efforts were then conducted, as required, to adequately characterize the site. Characterization of the Double Tracks Test Site was conducted in accordance with the US Department of Energy`s (DOE) Streamlined Approach for Environmental Restoration (SAFER).
Brucella endocarditis on double valvular prosthesis.
Lezaun, R; Teruel, J.; Maître, M. J.; De Artaza, M
1980-01-01
The case is reported of a 48-year-old man suffering from Brucella endocarditis on a double prosthesis. The successful medical and surgical treatment is described. So far as the authors know, this is the first report of Brucella endocarditis from a heart valve prosthesis.
From HHMI: Doubling Down on Diversity.
Asai, David J; Bauerle, Cynthia
2016-01-01
In spite of modest gains in the past four decades, the United States has not been able to substantially improve on the pervasive underrepresentation of minorities in postsecondary science, technology, engineering, and mathematics (STEM) pathways. We suggest a way to guide a national effort to double the persistence of underrepresented minorities in STEM in the next decade. PMID:27587852
Double beta decay: A theoretical overview
Energy Technology Data Exchange (ETDEWEB)
Rosen, S.P.
1988-01-01
This paper reviews the theoretical possibility of double beta decay. The titles of the main sections of this paper are: Nuclear physics setting; Particle physics requirements; Kinematical features of the decay modes; Nuclear matrix elements; the Shell model and two-neutrino decay; Quasi-particle random phase approximation; and Future considerations. 18 refs., 7 tabs. (LSP)
Doubling phenomena in first language acquisition
van Kampen, N.J.; Evers, A.
2006-01-01
Scope-bearing items for sentential negations and sentential questions appear in Dutch child language as ‘doubling’ constructions. A <+neg> or <+Q> element appears in sentence-initial position and is doubled in sentence-final position. The ‘doubling’ is not part of the adult system nor is it part of
Correlations in the hadronic double diffractive dissociation
International Nuclear Information System (INIS)
A given reaction of double diffractive dissociation is studied based on the three-component Deck Model. The correlations among the diffractive slope, the effective mass of the dissociated particle sub-system and the dissociation angle in the Gottfried-Jackson are studied based in this model. 9 refs, 19 figs
Under the Gaze of Double Critique
DEFF Research Database (Denmark)
Sabih, Joshua
2015-01-01
theory of double critique: decolonisation, desacralisation and the orphan book are operative in Ḫaṭībī´s analysis of Orientalism, identity, and the issue of origin. As a professional outsider, Ḫaṭībī follows conceptually and methodologically the rules of the epistemological critique in an enunciation of...
Lepton nonconservation and double beta decay
International Nuclear Information System (INIS)
This paper reviews the status of double beta decay as a test of lepton number conservation. Present limits on the mass of a Majorana neutrino are in the range of 10 to 50 eV. Experiments now in progress should substantially improve these limits
A Morphism Double Category and Monoidal Structure
Directory of Open Access Journals (Sweden)
Saikat Chatterjee
2013-01-01
Full Text Available We provide a recipe for “fattening” a category that leads to the construction of a double category. Motivated by an example where the underlying category has vector spaces as objects, we show how a monoidal category leads to a law of composition, satisfying certain coherence properties, on the object set of the fattened category.
Long term prospects for double beta decay
Zuber, K.
2010-01-01
In rather general terms the long term perspective of double beta decay is discussed. All important experimental parameters are investigated as well as the status of nuclear matrix element issues. The link with other neutrino physics results and options to disentangle the underlying physics process are presented.
Double-hit and double-protein-expression lymphomas: aggressive and refractory lymphomas.
Sarkozy, Clémentine; Traverse-Glehen, Alexandra; Coiffier, Bertrand
2015-11-01
Double-hit lymphoma (DHL) is a subgroup of aggressive lymphomas with both MYC and BCL2 gene rearrangements, characterised by a rapidly progressing clinical course that is refractory to aggressive treatment and short survival. Over time, the definition was modified and now includes diffuse large B-cell lymphoma (DLBCL) with MYC translocation combined with an additional translocation involving BCL2 or BCL6. Some cases that have a similar clinical course with concomitant overexpression of MYC or BCL2 proteins were recently characterised as immunohistochemical double-hit lymphomas (ie, double-protein-expression lymphomas [DPLs]). The clinical course of these DPLs is worse than so-called standard DLBCL but suggested by some studies to be slightly better than DHL, although there is overlap between the two categories. Present treatment does not allow cure or long-term survival in patients with genetic or immunohistochemical double-hit lymphomas, but several new drugs are being developed. PMID:26545844
The conducting form of gramicidin A is a right-handed double-stranded double helix
Burkhart, B. M.; Li, N.; Langs, D A; Pangborn, W A; Duax, W L
1998-01-01
The linear pentadecapeptide antibiotic, gramicidin D, is a naturally occurring product of Bacillus brevis known to form ion channels in synthetic and natural membranes. The x-ray crystal structures of the right-handed double-stranded double-helical dimers (DSDHℛ) reported here agree with 15N-NMR and CD data on the functional gramicidin D channel in lipid bilayers. These structures demonstrate single-file ion transfer through the channels. The results also indicate that previous crystal struct...
Alotaibi, Hessa M.; Sanders, Barry C
2015-01-01
For Doppler-broadened media operating under double-double electromagnetically induced transparency (EIT) conditions, we devise a scheme to control and reduce the probe-field group velocity at the center of the second transparency window. We derive numerical and approximate analytical solutions for the width of EIT windows and for the group velocities of the probe field at the two distinct transparency windows, and we show that the group velocities of the probe field can be lowered by judiciou...
Yang, Ming-Jie; Tseng, Jen-Yu; Chen, Chih-Yao; Li, Hsin-Yang
2015-12-01
Uterine anomalies involving a double uterus, double cervix, also known as didelphys uterus, and complete septate vagina are rarely seen and have an associated fertility problem. However, artificial reproductive technology with embryo transfers can help solve this fertility challenge. Conception in the uterus in just one side is commonly seen for embryos, which are always transferred through the usually used (dilated) vagina. We here present a patient with the above uterine anomaly who conceived with the aid of in vitro fertilization and embryo transfer to both uterine cavities under general anesthesia, which resulted in successful double singleton pregnancies with one fetus in each uterus. With intensive prenatal care, the pregnancy course for each fetus was rather uneventful. Although both fetuses were in cephalic presentation, cesarean section was performed at the 39(th) week of gestation with good outcomes in order to preclude anticipated difficulties if the baby had been delivered through the rarely dilated vagina. However, order of birth between the two fetuses was a crucial decision during the operation. PMID:26462956
Progress Toward Doubling the Beam Power at Fermilab's Accelerator Complex
Kourbanis, I.
2014-01-01
After a 14 month shutdown accelerator modifications and upgrades are in place to allow us doubling of the Main Injector beam power. We will discuss the past MI high power operation and the current progress towards doubling the power.
Proceedings of the LAMPF workshop on pion double charge exchange
International Nuclear Information System (INIS)
Experimental and theoretical aspects of double-analog, nonanalog, and continuum pion double charge exchange in the 50- to 310-MeV energy range are covered. Separate abstracts were prepared for 22 papers in these proceedings
Double photoionization of helium with synchrotron x-rays: Proceedings
International Nuclear Information System (INIS)
This report contains papers on the following topics: Overview and comparison of photoionization with charged particle impact; The ratio of double to single ionization of helium: the relationship of photon and bare charged particle impact ionization; Double photoionization of helium at high energies; Compton scattering of photons from electrons bound in light elements; Electron ionization and the Compton effect in double ionization of helium; Elimination of two atomic electrons by a single energy photon; Double photoionization of helium at intermediate energies; Double Photoionization: Gauge Dependence, Coulomb Explosion; Single and Double Ionization by high energy photon impact; The effect of Compton Scattering on the double to single ionization ratio in helium; and Double ionization of He by photoionization and Compton scattering. These papers have been cataloged separately for the database
Double Stem Cell Transplant May Help Fight a Childhood Cancer
... https://medlineplus.gov/news/fullstory_159243.html Double Stem Cell Transplant May Help Fight a Childhood Cancer Tandem ... better chance of survival if they receive two stem cell transplants, a new study reports. The double stem ...
Double Stem Cell Transplant May Help Fight a Childhood Cancer
... nih.gov/medlineplus/news/fullstory_159243.html Double Stem Cell Transplant May Help Fight a Childhood Cancer Tandem ... better chance of survival if they receive two stem cell transplants, a new study reports. The double stem ...
The Absorption Characteristics of Inhomogeneous Double-Clad Fibers
Institute of Scientific and Technical Information of China (English)
Hui Zhang; Zihua Wang; Zhongyin Xiao
2003-01-01
The absorption characteristics of radially inhomogeneous double-clad fiber (DCF) are investigated firstly with the method of caustic radius, combined with the method of WKBJ. The results are significant for double-clad optical fiber lasers and amplifiers.
Fermion doubling and Berenstein-Maldacena-Nastase correspondence
International Nuclear Information System (INIS)
We show that the string bit model suffers from doubling in the fermionic sector. The doubling leads to strong violation of supersymmetry in the limit N→∞. Since there is an exact correspondence between string bits and the algebra of BMN operators even at finite N, doubling is expected also on the side of super-Yang-Mills theory. We discuss the origin of the doubling in the BMN sector
Monitoring of Double Stud Wall Moisture Conditions in the Northeast
Energy Technology Data Exchange (ETDEWEB)
Ueno, K.
2015-03-01
Double-stud walls insulated with cellulose or low-density spray foam can have R-values of 40 or higher. However, double stud walls have a higher risk of interior-sourced condensation moisture damage, when compared with high-R approaches using exterior insulating sheathing.; Moisture conditions in double stud walls were monitored in Zone 5A (Massachusetts); three double stud assemblies were compared.
Fermion Doubling and Berenstein--Maldacena--Nastase Correspondence
Bellucci, Stefano; Sochichiu, Corneliu
2003-01-01
We show that the string bit model suffers from doubling in the fermionic sector. The doubling leads to strong violation of supersymmetry in the limit $N\\to\\infty$. Since there is an exact correspondence between string bits and the algebra of BMN operators even at finite $N$, doubling is expected also on the side of super-Yang--Mills theory. We discuss the origin of the doubling in the BMN sector.
Improving Woody Biomass Estimation Efficiency Using Double Sampling
B. Scott Shouse; Lhotka, John M.; Songlin Fei; Parrott, David L.
2012-01-01
Although double sampling has been shown to be an effective method to estimate timber volume in forest inventories, only a limited body of research has tested the effectiveness of double sampling on forest biomass estimation. From forest biomass inventories collected over 9,683 ha using systematic point sampling, we examined how a double sampling scheme would have affected precision and efficiency in these biomass inventories. Our results indicated that double sample methods would have yielded...
Double-sided microtron at Nihon University
International Nuclear Information System (INIS)
Construction of a 35 MeV cw double-sided microtron (DSM) at Nihon University was started in 1984 and completed in the spring of 1989. This machine was constructed as a proto-type of an 1 GeV cw double sided microtron for a medical pion facility and test accelerator for FEL and other applications. The 4.55 MeV electron beam from 5 MeV injector linac is injected to the DSM. The energy gain is 6 MeV at each turn acceleration. After recirculated 5 times, the electron beam with 34.5 MeV is extracted at the final short straight section. The DAW structure is used for all the accelerating tubes including the injector linac. Total rf power of 200 kW is provided by four 50 kW klystrons of 2450 MHz. (author)
Double-difference adjoint seismic tomography
Yuan, Yanhua O; Tromp, Jeroen
2016-01-01
We introduce a `double-difference' method for the inversion for seismic wavespeed structure based on adjoint tomography. Differences between seismic observations and model predictions at individual stations may arise from factors other than structural heterogeneity, such as errors in the assumed source-time function, inaccurate timings, and systematic uncertainties. To alleviate the corresponding nonuniqueness in the inverse problem, we construct differential measurements between stations, thereby reducing the influence of the source signature and systematic errors. We minimize the discrepancy between observations and simulations in terms of the differential measurements made on station pairs. We show how to implement the double-difference concept in adjoint tomography, both theoretically and in practice. We compare the sensitivities of absolute and differential measurements. The former provide absolute information on structure along the ray paths between stations and sources, whereas the latter explain relat...
Double Image Design in Newspaper Production
Directory of Open Access Journals (Sweden)
Mario Barišić
2010-01-01
Full Text Available In the high circulation production of daily newspapers, a double image, double information is set under the rules of Infraredesign theory (Pap et al, 2010. The management of visible and near infrared is posted with process colors for color setting configured for conventional newspaper print. The place of imprint that has delimited information in vs (Visible Spectrum and nir (Near InfraRed is called “a print with an infrared effect,” or conditionally “a print with infrared colors.” Daily newspapers, as massive carriers of information made by printing technique, are receiving a new form of presentation: printed image with a built-in invisible image.
Systematics of pion double charge exchange
International Nuclear Information System (INIS)
Differential cross sections have been measured for pion-induced double-charge-exchange (DCX) reactions leading to double-isobaric-analog states (DIAS) and low-lying nonanalog states in the residual nuclei. A description of the experimental details and data analysis is presented. The experimentally observed systematics of reactions leading to DIAS, to nonanalog ground states, and to low-lying 2+ states are described. Lowest-order optical-model calculations of DIAS DCX are compared to the data. Efforts to understand the anomalies by invoking additional reaction-mechanism amplitudes and a higher-order optical potential are described. Calculations of nonanalog DCX reactions leading to J/sup π/ = 0+ states were performed within a distorted-wave impulse-approximation framework. The sensitivities of these calculations to input parameters are discussed. 58 refs., 41 figs., 16 tabs
Representation of superoperators in double phase space
International Nuclear Information System (INIS)
Operators in quantum mechanics—either observables, density or evolution operators, unitary or not—can be represented by c-numbers in operator bases. The position and momentum bases are in one-to-one correspondence with lagrangian planes in double phase space, but this is also true for the well known Wigner–Weyl correspondence based on translation and reflection operators. These phase space methods are here extended to the representation of superoperators. We show that the Choi–Jamiolkowsky isomorphism between the dynamical matrix and the linear action of the superoperator constitutes a ‘double’ Wigner or chord transform when represented in double phase space. As a byproduct several previously unknown integral relationships between products of Wigner and chord distributions for pure states are derived. (paper)
Amplitude determinant coupled cluster with pairwise doubles
Zhao, Luning
2016-01-01
Recently developed pair coupled cluster doubles (pCCD) theory successfully reproduces doubly occupied configuration interaction (DOCI) with mean field cost. However, the projective nature of pCCD makes the method non-variational and thus hard to improve systematically. As a variational alternative, we explore the idea of coupled-cluster-like expansions based on amplitude determinants and develop a specific theory similar to pCCD based on determinants of pairwise doubles. The new ansatz admits a variational treatment through Monte Carlo methods while remaining size-consistent and, crucially, polynomial cost. In the dissociations of LiH, HF, H2O and N2, the method performs very similarly to pCCD and DOCI, suggesting that coupled-cluster-like ansatzes and variational evaluation may not be mutually exclusive.
JUNO and neutrinoless double beta decay
Ge, Shao-Feng; Rodejohann, Werner
2015-11-01
We study the impact of the precision determination of oscillation parameters in the JUNO experiment on half-life predictions for neutrinoless double beta decay. We show that the solar neutrino mixing angle can be measured by JUNO with below 1% uncertainty. This implies in particular that the minimal value of the effective mass in the inverted mass ordering will be known essentially without uncertainty. We demonstrate that this reduces the range of half-life predictions in order to test this value by a factor of 2. The remaining uncertainty is caused by nuclear matrix elements. This has important consequences for future double beta decay experiments that aim at ruling out the inverted mass ordering or the Majorana nature of neutrinos.
JUNO and Neutrinoless Double Beta Decay
Ge, Shao-Feng
2015-01-01
We study the impact of the precision determination of oscillation parameters in the JUNO experiment on half-life predictions for neutrinoless double beta decay. We show that the solar neutrino mixing angle can be measured by JUNO with below 1% uncertainty. This implies in particular that the minimal value of the effective mass in the inverted mass ordering will be known essentially without uncertainty. We demonstrate that this reduces the range of half-life predictions in order to test this value by a factor of two. The remaining uncertainty is caused by nuclear matrix elements. This has important consequences for future double beta decay experiments that aim at ruling out the inverted mass ordering or the Majorana nature of neutrinos.
Importance of neutrinoless double beta decay
Sarkar, Utpal
2007-01-01
A natural explanation for the smallness of the neutrino mass requires them to be Majorana particles violating lepton number by two units. Since lepton number violation can have several interesting consequences in particle physics and cosmology, it is of utmost importance to find out if there is lepton number violation in nature and what is its magnitude. The neutrinoless double beta decay experiment can answer these questions: if there is lepton number violation and if neutrinos are Majorana particles. In addition, the magnitude of neutrinoless double beta decay will constrain any other lepton number violating processes. This lepton number violation may also be relatd to the matter-antimatter asymmetry of the universe, dark matter and cosmological constant.
Phonon tunneling through a double barrier system
Energy Technology Data Exchange (ETDEWEB)
Villegas, Diosdado [Departamento de Física, Universidad Central “Marta Abreu” de Las Villas, CP 54830, Santa Clara, Villa Clara (Cuba); Instituto de Física, Universidad Autónoma de Puebla, 18 Sur y San Claudio, Edif. 110A, Ciudad Universitaria, 72570 Puebla (Mexico); León-Pérez, Fernando de [Centro Universitario de la Defensa de Zaragoza, Ctra. de Huesca s/n, E-50090 Zaragoza (Spain); Pérez-Álvarez, R. [Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, CP 62209 Cuernavaca (Mexico); Arriaga, J., E-mail: arriaga@ifuap.buap.mx [Instituto de Física, Universidad Autónoma de Puebla, 18 Sur y San Claudio, Edif. 110A, Ciudad Universitaria, 72570 Puebla (Mexico)
2015-04-15
The tunneling of optical and acoustic phonons at normal incidence on a double-barrier is studied in this paper. Transmission coefficients and resonance conditions are derived theoretically under the assumption that the long-wavelength approximation is valid. It is shown that the behavior of the transmission coefficients for the symmetric double barrier has a Lorentzian form close to resonant frequencies and that Breit–Wigner's formula have a general validity in one-dimensional phonon tunneling. Authors also study the so-called generalized Hartman effect in the tunneling of long-wavelength phonons and show that this effect is a numerical artifact resulting from taking the opaque limit before exploring the variation with a finite barrier width. This study could be useful for the design of acoustic devices.
A new double views motion deblurring method
Hong, Hanyu; Hua, Xia; Zhang, Wenmo; Shi, Yu
2015-12-01
With improving of intelligent and automation in modern industrial production area, the detection and reconstruction of the 3D surface of the product has become an important technology, but the image which acquire on the actual production line has motion blur and this problem will affect the later reconstruction work. In order to solve this problem, a deblurring method which based on double view moving target image is proposed in this paper. We can deduce the relationship of the point spread function(PSF) path between the double view image through the epipolar geometry and the camera model. The experimental results show that deblurring with the PSF path solved by the geometric relationship achieves good results.
Representation of superoperators in double phase space
Saraceno, Marcos; Ozorio de Almeida, Alfredo M.
2016-04-01
Operators in quantum mechanics—either observables, density or evolution operators, unitary or not—can be represented by c-numbers in operator bases. The position and momentum bases are in one-to-one correspondence with lagrangian planes in double phase space, but this is also true for the well known Wigner-Weyl correspondence based on translation and reflection operators. These phase space methods are here extended to the representation of superoperators. We show that the Choi-Jamiolkowsky isomorphism between the dynamical matrix and the linear action of the superoperator constitutes a ‘double’ Wigner or chord transform when represented in double phase space. As a byproduct several previously unknown integral relationships between products of Wigner and chord distributions for pure states are derived.
A double image Mach-Zehnder interferometer
Ramadan, W. A.; El-Tawargy, A. S.
2015-02-01
In this paper, we present a modified version of the Mach-Zehnder interferometer. An arrangement of two linear polarizers and a wave rotator has been inserted in the light's path. Using this new arrangement, we are able to obtain a double image of a birefringent fibre. This double image records the shifts of the Mach-Zehnder's fringes for the light vibrating parallel and perpendicular to the fibre's axis in the same image. Moreover, by controlling the beam splitters, we are able to get an overlap between two images of the fibre and to directly observe an image describing the birefringence of the investigated fibre. This new arrangement has been applied to three polypropylene fibres and a graded-index FOS optical fibre in order to demonstrate its validity and powerful ability for monitoring the direct birefringence. A set of images of the investigated samples is presented and compared with images obtained using the classical Mach-Zehnder interferometer.
Dynamically possible pattern speeds of double bars
Maciejewski, Witold
2009-01-01
The method to study oscillating potentials of double bars, based on invariant loops, is introduced here in a new way, intended to be more intelligible. Using this method, I show how the orbital structure of a double-barred galaxy (nested bars) changes with the variation of nuclear bar's pattern speed. Not all pattern speeds are allowed when the inner bar rotates in the same direction as the outer bar. Below certain minimum pattern speed orbital support for the inner bar abruptly disappears, while high values of this speed lead to loops that are increasingly round. For values between these two extremes, loops supporting the inner bar extend further out as its pattern speed decreases, and they become more eccentric and pulsate more. These findings do not apply to counter-rotating inner bars.
Recursive double-size fixed precision arithmetic
Chabot, Christophe; Fousse, Laurent; Giorgi, Pascal
2011-01-01
This work is a part of the SHIVA (Secured Hardware Immune Versatile Architecture) project whose purpose is to provide a programmable and reconfigurable hardware module with high level of security. We propose a recursive double-size fixed precision arithmetic called RecInt. Our work can be split in two parts. First we developped a C++ software library with performances comparable to GMP ones. Secondly our simple representation of the integers allows an implementation on FPGA. Our idea is to consider sizes that are a power of 2 and to apply doubling techniques to implement them efficiently: we design a recursive data structure where integers of size 2^k, for k>k0 can be stored as two integers of size 2^{k-1}. Obviously for k<=k0 we use machine arithmetic instead (k0 depending on the architecture).
Towards weakly constrained double field theory
Lee, Kanghoon
2016-08-01
We show that it is possible to construct a well-defined effective field theory incorporating string winding modes without using strong constraint in double field theory. We show that X-ray (Radon) transform on a torus is well-suited for describing weakly constrained double fields, and any weakly constrained fields are represented as a sum of strongly constrained fields. Using inverse X-ray transform we define a novel binary operation which is compatible with the level matching constraint. Based on this formalism, we construct a consistent gauge transform and gauge invariant action without using strong constraint. We then discuss the relation of our result to the closed string field theory. Our construction suggests that there exists an effective field theory description for massless sector of closed string field theory on a torus in an associative truncation.
New Cosmological Signatures from Double Field Theory
Wu, Houwen
2013-01-01
In cosmology, it has been a long-standing problem to establish a \\emph{parameter insensitive} evolution from an anisotropic phase to an isotropic phase. On the other hand, it is of great importance to construct a theory having extra dimensions as its intrinsic ingredients. We show that these two problems are closely related and can naturally be solved simultaneously in double field theory cosmology. Our derivations are based on general arguments without any fine-tuning parameters. In addition, We find that the time reversal symmetry is broken and the pre- and post-big bangs are distinguishable. There is a visible and invisible dimension exchange between the pre- and post-big bangs. Our results indicate that double field theory has profound physical consequences and the continuous $O\\left(D,D\\right)$ is a very fundamental symmetry. This observation reinforces the viewpoint that symmetries dictate physics.
Double papilla flap technique for dual purpose
Directory of Open Access Journals (Sweden)
P Mohan Kumar
2012-01-01
Full Text Available Marginal tissue recession exposes the anatomic root on the teeth, which gives rise to -common patient complaints. It is associated with sensitivity, tissue irritation, cervical abrasions, and esthetic concerns. Various types of soft tissue grafts may be performed when recession is deep and marginal tissue health cannot be maintained. Double papilla flap is an alternative technique to cover isolated recessions and correct gingival defects in areas of insufficient attached gingiva, not suitable for a lateral sliding flap. This technique offers the advantages of dual blood supply and denudation of interdental bone only, which is less susceptible to permanent damage after surgical exposure. It also offers the advantage of quicker healing in the donor site and reduces the risk of facial bone height loss. This case report presents the advantages of double papilla flap in enhancing esthetic and functional outcome of the patient.
An instrument for measuring doubling time
International Nuclear Information System (INIS)
The instrument described here allows the direct and almost immediate measurement, with a precision of the order of 1 per cent, of the time taken by a reactor to double its power. The method of measurement consists of noting the instants when the power of the reactor passes the levels P1 and P2 such that P2 = 2 P1, and of measuring the time lapse between these two instants. The instrument picks out, in the course of one rise in power, several levels, P1, P2, P3... etc, chosen in such a manner as to give several successive measurements of the doubling time. It is also capable of making these same measurements when the reactor is working below the critical level. (author)
Summability of Double Independent Random Variables
Ekrem Savaş; Richard F. Patterson
2008-01-01
We will examine double sequence to double sequence transformation of independent identically distribution random variables with respect to four-dimensional summability matrix methods. The main goal of this paper is the presentation of the following theorem. If maxÃ¢ÂÂ¡k,l|am,n,k,l|=maxÃ¢ÂÂ¡k,l|am,kan,l|=O(mÃ¢ÂˆÂ’ÃŽÂ³1)O(nÃ¢ÂˆÂ’ÃŽÂ³2), ÃŽÂ³1,ÃŽÂ³2>0, then E|XÃ¢ÂŒÂ£|1+1/ÃŽÂ³1
Mosaic double aneuploidy: Down syndrome and XYY
Directory of Open Access Journals (Sweden)
Mayur Parihar
2013-01-01
Full Text Available Chromosomal abnormalities are seen in nearly 1% of live born infants. We report a 5-year-old boy with the clinical features of Down syndrome, which is the most common human aneuploidy. Cytogenetic analysis showed a mosaicism for a double aneuploidy, Down syndrome and XYY. The karyotype was 47, XY,+21[19]/48, XYY,+21[6]. ish XYY (DXZ1 × 1, DYZ1 × 2. Mosaic double aneuploidies are very rare and features of only one of the aneuploidies may predominate in childhood. Cytogenetic analysis is recommended even if the typical features of a recognized aneuploidy are present so that any associated abnormality may be detected. This will enable early intervention to provide the adequate supportive care and management.
Mosaic double aneuploidy: Down syndrome and XYY.
Parihar, Mayur; Koshy, Beena; Srivastava, Vivi Miriam
2013-07-01
Chromosomal abnormalities are seen in nearly 1% of live born infants. We report a 5-year-old boy with the clinical features of Down syndrome, which is the most common human aneuploidy. Cytogenetic analysis showed a mosaicism for a double aneuploidy, Down syndrome and XYY. The karyotype was 47, XY,+21[19]/48, XYY,+21[6]. ish XYY (DXZ1 × 1, DYZ1 × 2). Mosaic double aneuploidies are very rare and features of only one of the aneuploidies may predominate in childhood. Cytogenetic analysis is recommended even if the typical features of a recognized aneuploidy are present so that any associated abnormality may be detected. This will enable early intervention to provide the adequate supportive care and management. PMID:24339550
Double layer capacitance of carbon foam electrodes
Delnick, F. M.; Ingersoll, D.; Firsich, D.
We have evaluated a wide variety of microcellular carbon foams prepared by the controlled pyrolysis and carbonization of several polymers including: polyacrylonitrile (PAN), polymethacrylonitrile (PMAN), resorcinol/formaldehyde (RF), divinylbenzene/methacrylonitrile (DVB), phenolics (furfuryl/alcohol), and cellulose polymers such as Rayon. The porosity may be established by several processes including: gelation (1-5), phase separation (1-3,5-8), emulsion (1,9,10), aerogel/xerogel formation (1,11,12,13), replication (14), and activation. In this report we present the complex impedance analysis and double layer charging characteristics of electrodes prepared from one of these materials for double layer capacitor applications, namely activated cellulose derived microcellular carbon foam.
Search for Neutrinoless Double-Beta Decay
Tornow, Werner
2014-01-01
After the pioneering work of the Heidelberg-Moscow (HDM) and International Germanium Experiment (IGEX) groups, the second round of neutrinoless double-$\\beta$ decay searches currently underway has or will improve the life-time limits of double-$\\beta$ decay candidates by a factor of two to three, reaching in the near future the $T_{1/2} = 3 \\times 10^{25}$ yr level. This talk will focus on the large-scale experiments GERDA, EXO-200, and KamLAND-Zen, which have reported already lower half-life time limits in excess of $10^{25}$ yr. Special emphasis is given to KamLAND-Zen, which is expected to approach the inverted hierarchy regime before future 1-ton experiments probe completely this life-time or effective neutrino-mass regime, which starts at $\\approx 2 \\times 10^{26}$ yr or $\\approx 50$ meV.
Double-contingency implementation at GE Wilmington
International Nuclear Information System (INIS)
At General Electric's Nuclear Energy Production Facility, the double-contingency principle is implemented for most operations by dual-parameter control; i.e., controls must be established on two different and independent parameters so that if one parameter control is lost, the other parameter prevents a criticality from occurring. This implementation method, as discussed later, has many advantages. Note that some small-scale lab operations as well as a waste treatment operation have single-parameter control to which dual independent controls must be provided to achieve double-contingency protection. These activities with single-parameter control have been specifically licensed by the U.S. Nuclear Regulatory Commission (NRC)
Machine learning bandgaps of double perovskites
Pilania, G.; Mannodi-Kanakkithodi, A.; Uberuaga, B. P.; Ramprasad, R.; Gubernatis, J. E.; Lookman, T.
2016-01-01
The ability to make rapid and accurate predictions on bandgaps of double perovskites is of much practical interest for a range of applications. While quantum mechanical computations for high-fidelity bandgaps are enormously computation-time intensive and thus impractical in high throughput studies, informatics-based statistical learning approaches can be a promising alternative. Here we demonstrate a systematic feature-engineering approach and a robust learning framework for efficient and accurate predictions of electronic bandgaps of double perovskites. After evaluating a set of more than 1.2 million features, we identify lowest occupied Kohn-Sham levels and elemental electronegativities of the constituent atomic species as the most crucial and relevant predictors. The developed models are validated and tested using the best practices of data science and further analyzed to rationalize their prediction performance.
Double-slit experiment in momentum space
Ivanov, I P; Surzhykov, A; Fritzsche, S
2016-01-01
Young's classic double-slit experiment demonstrates the reality of interference when waves and particles travel simultaneously along two different spatial paths. Here, we propose a double-slit experiment in momentum space. We show that elastic scattering of vortex electrons proceeds via two paths in momentum space, which are well localized and well separated from each other. For such vortex beams, the (plane-wave) amplitudes along the two paths acquire adjustable phase shifts and produce interference fringes in the final angular distribution. We argue that this experiment can be realized with the present day technology. We show that it gives experimental access to the Coulomb phase, a quantity which plays an important role in all charged particle scattering but which usual scattering experiments are insensitive to.
Parametric study of double cellular detonation structure
Khasainov, B.; Virot, F.; Presles, H.-N.; Desbordes, D.
2013-05-01
A parametric numerical study is performed of a detonation cellular structure in a model gaseous explosive mixture whose decomposition occurs in two successive exothermic reaction steps with markedly different characteristic times. Kinetic and energetic parameters of both reactions are varied in a wide range in the case of one-dimensional steady and two-dimensional (2D) quasi-steady self-supported detonations. The range of governing parameters of both exothermic steps is defined where a "marked" double cellular structure exists. It is shown that the two-level cellular structure is completely governed by the kinetic parameters and the local overdrive ratio of the detonation front propagating inside large cells. Furthermore, since it is quite cumbersome to use detailed chemical kinetics in unsteady 2D case, the proposed work should help to identify the mixtures and the domain of their equivalence ratio where double detonation structure could be observed.
Tunneling rate in double quantum dots
Filikhin, Igor; Matinyan, Sergei; Vlahovic, Branislav
2014-03-01
We study spectral properties of electron tunneling in double quantum dots (DQDs) (and double quantum wells (DQWs)) and their relation to the geometry. In particular we compare the tunneling in DQW with chaotic and regular geometry, taking into account recent evidence about regularization of the tunneling rate when the QW geometry is chaotic. Our calculations do not support this assumption. We confirm high influence of the QW geometry boundaries on the rate fluctuation along the spectrum. The factors of the effective mass anisotropy and violation of the symmetry of DQD and DQW are also considered. Generally, we found that the small violation of the symmetry drastically affects tunneling. This work is supported by the NSF (HRD-0833184) and NASA (NNX09AV07A).
Towards Weakly Constrained Double Field Theory
Lee, Kanghoon
2015-01-01
We show that it is possible to construct a well-defined effective field theory incorporating string winding modes without using strong constraint in double field theory. We show that X-ray (Radon) transform on a torus is well-suited for describing weakly constrained double fields, and any weakly constrained fields are represented as a sum of strongly constrained fields. Using inverse X- ray transform we define a novel binary operation which is compatible with the level matching constraint. Based on this formalism, we construct a consistent gauge transform and gauge invariant action without using strong constraint. We then discuss the relation of our result to the closed string field theory. Our construction suggests that there exists an effective field theory description for massless sector of closed string field theory on a torus in an associative truncation.
Towards weakly constrained double field theory
Directory of Open Access Journals (Sweden)
Kanghoon Lee
2016-08-01
Full Text Available We show that it is possible to construct a well-defined effective field theory incorporating string winding modes without using strong constraint in double field theory. We show that X-ray (Radon transform on a torus is well-suited for describing weakly constrained double fields, and any weakly constrained fields are represented as a sum of strongly constrained fields. Using inverse X-ray transform we define a novel binary operation which is compatible with the level matching constraint. Based on this formalism, we construct a consistent gauge transform and gauge invariant action without using strong constraint. We then discuss the relation of our result to the closed string field theory. Our construction suggests that there exists an effective field theory description for massless sector of closed string field theory on a torus in an associative truncation.
Double photoionization of lithium at medium energies
International Nuclear Information System (INIS)
Full text: The double-to-single photoionization ratio of atomic lithium has been measured for photon energies ranging from 120 eV to 910 eV . Through the extensive use of various filters we were able to significantly extend the previous range of measurements. We d that our data are in agreement with the predicted high-energy limit of 3.4%. By applying simple model curves to our data, we attempt to disentangle the different processes leading to a doubly charged Li ion. Our model corroborates the notion that sequential processes contribute substantially to the double-photoionization cross-section ratio as predicted by theory. This work was supported by NSF under Grant No. PHY-9987638. The SRC is supported by NSF Grant No. DMR-0084402. M.M.M. acknowledges financial support through the NSF REU program
Cosmic Topology of Double Action Manifolds
Aurich, Ralf
2012-01-01
The cosmic microwave background (CMB) anisotropies in spherical 3-spaces with a non-trivial topology are studied. This paper discusses the special class of the so-called double action manifolds, which are for the first time analysed with respect to their CMB anisotropies. The CMB anisotropies are computed for all double action manifolds generated by a dihedral and a cyclic group with a group order of up to 180 leading to 33 different topologies. Several spaces are found which show a suppression of the CMB anisotropies on large angular distances as it is found on the real CMB sky. It turns out that these spaces possess fundamental cells defined as Voronoi domains which are close to highly symmetric polyhedra like Platonic or Archimedean ones.
The coalescence rates of double black holes
Belczynski, Krzysztof; Bulik, Tomasz; Dominik, Michal; Prestwich, Andrea
2011-01-01
We present the summary of the recent investigations of double black hole binaries in context of their formation and merger rates. In particular we discuss the spectrum of black hole masses, the formation scenarios in the local Universe and the estimates of detection rates for gravitational radiation detectors like LIGO and VIRGO. Our study is based on observed properties of known Galactic and extra-galactic stellar mass black holes and evolutionary predictions. We argue that the binary black ...
Green taxes by doubling energy levies
International Nuclear Information System (INIS)
An overview is given of green taxes, levies and investment facilities in the Netherlands. Also, attention is paid to the main issues in the Third Dutch National Environmental Plan (NMP3). Energy levies are imported for the Dutch government to shift taxes on labor further towards taxes on pollution. However, the proposed doubling of the energy levies meets strong opposition from industry and businesses. 2 fig., 3 tabs
Vitrectomy in double-perforation gunshot injury
Directory of Open Access Journals (Sweden)
Abd El Alim Mohamed A
2013-11-01
Full Text Available Ahmed Abd El Alim MohamedOphthalmology department, Ain Shams University, Cairo, EgyptObjective: This study sought to evaluate the result of pars plana vitrectomy in patients with gunshot wounds involving double perforation.Methods: This was a retrospective, noncomparative, interventional case series.Results: Eighteen patients (18 eyes with double-perforation gunshot injuries were treated from February 2010 to March 2012. The group included 16 men (88% and two women (11%; the mean age was 24 (15–33 years. In each case, vitrectomy was scheduled 1–6 weeks after repair of the entrance site. Associated retinal detachments were observed in two eyes (11%, retinal incarceration was observed surrounding the exit site in three eyes (16%, and retention of an intraocular foreign body was observed in two cases. After a follow-up period of 8 ± 2 months, two eyes (11% had achieved visual acuity (VA of 0.5, nine eyes (50% had achieved VA between 0.5 and 0.1, and seven eyes (38% had achieved VA between 0.1 and hand movement. The main reasons for functional failure (VA 0.1 to hand movement were macular dragging (due to fibrosis at the exit site near the macula in seven cases (38%, submacular hemorrhage in four cases (22%, and epimacular fibrosis in five cases (27%. All cases developed postoperative exotropia. One case (5% developed postoperative hemorrhage. No cases exhibited signs of postoperative redetachment.Conclusion: The outcome of pars plana vitrectomy in cases with double perforations is variable. Factors including the surgeon's skill level, the time to surgery, and the efficacy of the intraocular tamponade affect the postoperative outcome.Keywords: pars plana vitrectomy, gunshot injury, double perforation
Recursive double-size fixed precision arithmetic
Chabot, Christophe; Dumas, Jean-Guillaume; Fousse, Laurent; Giorgi, Pascal
2011-01-01
This work is a part of the SHIVA (Secured Hardware Immune Versatile Architecture) project whose purpose is to provide a programmable and reconfigurable hardware module with high level of security. We propose a recursive double-size fixed precision arithmetic called RecInt. Our work can be split in two parts. First we developped a C++ software library with performances comparable to GMP ones. Secondly our simple representation of the integers allows an implementation on FPGA. Our idea is to co...
Predecessors of Double-Entry Accounting
Mykhaylo Kuter; Maryna Gurskaya; Artem Musaelyan
2013-01-01
The article covers analysis of some historically significant issues of accounting development in the home-country of contemporary accounting made with reference to the archived materials found in Italy. In particular, the issue of purpose and order of taking entries in the book titled 'RICORDANZE' ('Memorials') has been considered. Resulting from the analysis done, the significance has been grounded for keeping accounting records which do not subject to double-entry principle thus being busin...
Analysis of Hashrate-Based Double Spending
Rosenfeld, Meni
2014-01-01
Bitcoin is the world's first decentralized digital currency. Its main technical innovation is the use of a blockchain and hash-based proof of work to synchronize transactions and prevent double-spending the currency. While the qualitative nature of this system is well understood, there is widespread confusion about its quantitative aspects and how they relate to attack vectors and their countermeasures. In this paper we take a look at the stochastic processes underlying typical attacks and th...
Double dumb-bell calculus in childhood
Directory of Open Access Journals (Sweden)
Joshi Prashant
2009-01-01
Full Text Available An eight-year old male was admitted with complaints of right scrotal swelling, dysuria and intermittent retention of urine for 10 days. On per-rectal examination, a hard mass was palpable in the posterior urethra. An X-ray (KUB of the abdomen revealed a double dumb-bell calculus at the base of bladder, extending into the posterior urethra. A cystolithotomy via the suprapubic approach was successfully curative.
Double layers are not particle accelerators
International Nuclear Information System (INIS)
It is pointed out that the continuing advocacy of electrostatic double layers as particle accelerators in the aurora and other space and astrophysical plasmas is fundamentally unsound. It is suggested furthermore that there is little reason to invoke static or quasi-static electric fields as the cause of auroral electron acceleration. Stochastic acceleration by electrostatic wave turbulence appears to present a natural explanation for this and for electron acceleration in other space and astrophysical plasmas. (author)
Tables of double beta decay data
International Nuclear Information System (INIS)
A compilation of experimental data on double beta decay is presented. The tables contain the most stringent known experimental limits or positive results of 2β transitions of 69 natural nuclides to ground and excited states of daughter nuclei for different channels (2β-; 2β+; εβ+; 2ε) and modes (0ν; 2ν; 0νM) of decay. (authors). 189 refs., 9 figs., 3 tabs
Tables of double beta decay data
Energy Technology Data Exchange (ETDEWEB)
Tretyak, V.I. [AN Ukrainskoj SSR, Kiev (Ukraine)]|[Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Zdesenko, Y.G. [AN Ukrainskoj SSR, Kiev (Ukraine)
1995-12-31
A compilation of experimental data on double beta decay is presented. The tables contain the most stringent known experimental limits or positive results of 2{beta} transitions of 69 natural nuclides to ground and excited states of daughter nuclei for different channels (2{beta}{sup -}; 2{beta}{sup +}; {epsilon}{beta}{sup +}; 2{epsilon}) and modes (0{nu}; 2{nu}; 0{nu}M) of decay. (authors). 189 refs., 9 figs., 3 tabs.
Double charm states in QCD sum rules
International Nuclear Information System (INIS)
In this note we revisit and improve the calculation of the Tcc mass using the double ratio of QCD sum rules (QCDSR), assuming that this state is described by a molecular current. In a previous work we used a tetraquark current. We conclude that with both currents we arrive at nearly the same results for the Tcc mass, which turns out to be close to the mass of the X(3872).
The double tetrahedron structure of the nucleus
Garai, Jozsef
2003-01-01
Expanding a double tetrahedron formation of equal spheres arranged in fcc structure correlation between the positions of the nucleons and quantum numbers has been detected. The number of protons in the structure is not simply consistent with all the corresponding quantum numbers but also bears the same physical meaning as in quantum mechanics. The detected correlations between lattice positions of the protons and quantum numbers raise the possibility the solid nuclear structure might be able ...
JUNO and Neutrinoless Double Beta Decay
Ge, Shao-Feng; Rodejohann, Werner
2015-01-01
We study the impact of the precision determination of oscillation parameters in the JUNO experiment on half-life predictions for neutrinoless double beta decay. We show that the solar neutrino mixing angle can be measured by JUNO with below 1% uncertainty. This implies in particular that the minimal value of the effective mass in the inverted mass ordering will be known essentially without uncertainty. We demonstrate that this reduces the range of half-life predictions in order to test this v...
Particle Swarm Optimization with Double Learning Patterns
Yuanxia Shen; Linna Wei; Chuanhua Zeng; Jian Chen
2015-01-01
Particle Swarm Optimization (PSO) is an effective tool in solving optimization problems. However, PSO usually suffers from the premature convergence due to the quick losing of the swarm diversity. In this paper, we first analyze the motion behavior of the swarm based on the probability characteristic of learning parameters. Then a PSO with double learning patterns (PSO-DLP) is developed, which employs the master swarm and the slave swarm with different learning patterns to achieve a trade-off...
Layered Double Hydroxide as Cordycepin Delivery Nanocarrier
Institute of Scientific and Technical Information of China (English)
Qin Zheng YANG; Jing YANG; Chang Kai ZHANG
2006-01-01
Layered double hydroxide was investigated as cordycepin delivery nanocarrier for the first time in this study. Negatively charged biomolecule-cordycepin was intercalated in the gallery spaces of [Mg-Al-NO3], which was confirmed by the results of X-ray diffraction and electrophoretic mobility. Cell experiment suggested that the new bio-LDH nanohybrid could prevent cordycepin decomposition by adenosine deaminase. This new formulation could possibly be used as a novel form cordycepin intravenous injection.
Cantor Spectra for Double Exchange Model
Satou, Atsuo; Yamanaka, Masanori
2000-01-01
We numerically study energy spectra and localization properties of the double exchange model at irrational filling factor. To obtain variational ground state, we use a mumerical technique in momentum space by ``embedded'' boundary condition which has no finite size effect a priori. Although the Hamiltonian has translation invariance, the ground state spontaneously exhibits a self-similarity. Scaling and multi-fractal analysis for the wave functions are performed and the scaling indices $\\alph...
Preparation of double-walled carbon nanotubes
Institute of Scientific and Technical Information of China (English)
JIANG Bin; WEI Jinquan; CI Lijie; WU Dehai
2004-01-01
Double-walled carbon nanotubes were prepared using the floating chemical vapor deposition with methane as carbon source and adding small amount of sulfur into the ferrocene catalyst. The optimized technological parameters are: the reaction temperature is 1200℃; the catalyst vapor temperature is 80℃; the flow rate of argon is 2000 SCCM; the flow rate of methane is 5 SCCM. The purified DWNTs under these optimized technological parameters have high purity above 90 wt%.
Water Taxation and the Double Dividend Hypothesis
Nicholas Kilimani
2014-01-01
The double dividend hypothesis contends that environmental taxes have the potential to yield multiple benefits for the economy. However, empirical evidence of the potential impacts of environmental taxation in developing countries is still limited. This paper seeks to contribute to the literature by exploring the impact of a water tax in a developing country context, with Uganda as a case study. Policy makers in Uganda are exploring ways of raising revenue by taxing environmental goods such a...
The Double Paradox of Elementary Economics Education
Pol, Eduardo; Carroll, Peter
2005-01-01
Elementary economics textbooks have become less attractive to students requiring only an introduction to economics, given that their content is pervaded by mathematical diagrams and simple equations. Also they are of relatively little value to those interested in, for example, attempting to gain an understanding of the New Economy, for they rarely emphasise business innovation and its crucial dynamic role. These factors engender something of a double paradox. First (paradox of the tools and t...
NEUTRINOLESS DOUBLE BETA DECAY: AN EXTREME CHALLENGE
Fernando Ferroni
2013-01-01
Neutrino-less Double Beta Decay is the only known way to possibly resolve the nature of neutrino mass. The chances to cover the mass region predicted by the inverted hierarchy require a step forward in detector capability. A possibility is to make use of scintillating bolometers. These devices shall have a great power in distinguishing signals from alfa particles from those induced by electrons. This feature might lead to an almost background-free experiment. Here the Lucifer concept will be ...
Generalised double-logarithmic equation in QCD
Velizhanin, V N
2014-01-01
We present a generalisation of the double-logarithmic equation for the anomalous dimension of the non-singlet unpolarized twist-2 operators in QCD. Using known three-loop result this generalisation allows to predict a small x expansion of the four-loop non-singlet splitting functions in QCD for all power of logarithms up to the single-logarithm ln x term.
The monolithic double-threshold discriminator
Baturitsky, M A
1999-01-01
A double-threshold discriminator capable of processing input signals of different duration is described. Simplicity of the discriminator circuitry makes it possible to embody the discriminator in multichannel ICs using microwave bipolar-JFET technology. Time walk is calculated to be less than 0.35 ns for the input ramp signals with rise times 25-100 ns and amplitudes 50 mV-1 V.
Double regenerative amplification of picosecond pulses
Bai, Zhen-ao; Chen, Li-yuan; Bai, Zhen-xu; Chen, Meng; Li, Gang
2012-04-01
An double Nd:YAG regenerative amplification picosecond pulse laser is demonstrated under the semiconductor saturable absorption mirror(SESAM) mode-locking technology and regenerative amplification technology, using BBO crystal as PC electro-optic crystal. The laser obtained is 20.71ps pulse width at 10 KHz repetition rate, and the energy power is up to 4W which is much larger than the system without pre-amplification. This result will lay a foundation for the following amplification.
Compact modeling of Double-Gate MOSFETs
Lu, Huaxin
2006-01-01
Double-Gate (DG) MOSFET is a newly emerging device that can potentially further scale down CMOS technology owing to its excellent control of short channel effects. Currently, much research effort is devoted to the development of DG MOSFETs. This dissertation focuses on the compact modeling of DG MOSFETs, aiming to extract the physics of DG MOSFETs and provide a tool for simulating DG MOSFET circuits. We start from the basic Poisson's equation and current continuity equation to rigorously deri...
Simulation of double barrier resonant tunneling diodes
Porter, Roy M.
1996-01-01
The double barrier resonant tunneling diode (DBRTD) is one of several devices currently being considered by the semiconductor industry as a replacement for conventional very large scale integrated (VLSI) circuit technology when the latter reaches its currently perceived scaling limits. The DBRTD was one of the first and remains one of the most promising devices to exhibit a room temperature negative differential resistance (NDR); this non-linear device characteristic has innovative circuit ap...
Kinetics of the Double Carbonylation of Benzylchloride
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
It is a multi-phase-catalyzed reaction to produce calcium phenylpyruvate by double carbonylation of benzylchloride. Based on the analysis of the reaction mechanism, a kinetic model of the carbonylation reaction was obtained. The model was verified through experiments in which the diffusion effect was neglected with the appropriate operation manner. But it is inevitable that the carbonylation process is controlled by diffusion as the autoclave scaling up.
Generalized Valon Model for Double Parton Distributions
Broniowski, Wojciech; Golec-Biernat, Krzysztof
2016-01-01
We show how the double parton distributions may be obtained consistently from the many-body light-cone wave functions. We illustrate the method on the example of the pion with two Fock components. The procedure, by construction, satisfies the Gaunt-Stirling sum rules. The resulting single parton distributions of valence quarks and gluons are consistent with a phenomenological parametrization at a low scale.
A double pendulum model of tennis strokes
Cross, Rod
2011-05-01
The physics of swinging a tennis racquet is examined by modeling the forearm and the racquet as a double pendulum. We consider differences between a forehand and a serve, and show how they differ from the swing of a bat and a golf club. It is also shown that the swing speed of a racquet, like that of a bat or a club, depends primarily on its moment of inertia rather than on its mass.
Double Competition for Information-Theoretic SOM
Ryotaro Kamimura
2014-01-01
In this paper, we propose a new type of informationtheoretic method for the self-organizing maps (SOM), taking into account competition between competitive (output) neurons as well as input neurons. The method is called ”double competition”, as it considers competition between outputs as well as input neurons. By increasing information in input neurons, we expect to obtain more detailed information on input patterns through the information-theoretic method. We applied the informationtheoretic...
Many worlds interpretation for double slit experiment
Yun, Zinkoo
2014-01-01
As is well known, the double slit experiment contains every key concepts of quantum mechanics such as phase effect, probability wave, quantum interference, quantum superposition. In this article, I will clarify the meaning of quantum superposition in terms of phase effect between states. After applying standard quantum theory, it leads to serious questions about the unitary process of an isolated system. It implies that non collapsing interpretations including many worlds may not be justified...
Simulation Results of Double Forward Converter
P. Vijaya Kumar; S. Rama Reddy
2009-01-01
This work aims to find a better forward converter for DC to DC conversion.Simulation of double forward converter in SMPS system is discussed in this paper. Aforward converter with RCD snubber to synchronous rectifier and/or to current doubleris also discussed. The evolution of the forward converter is first reviewed in a tutorialfashion. Performance parameters are discussed including operating principle, voltageconversion ratio, efficiency, device stress, small-signal dynamics, noise and EMI....
Double sine-Gordon model revisited
International Nuclear Information System (INIS)
We reconsider the mass spectrum of double sine-Gordon theory where recent semiclassical results called into question the previously accepted picture. We use the truncated conformal space approach (TCSA) to investigate the claims. We demonstrate that the numerics supports the original results, and strongly disagrees with those obtained from semiclassical soliton form factor techniques. Besides the numerical analysis, we also discuss the underlying theoretical arguments
Comments on "Double-Wave Theory"
Institute of Scientific and Technical Information of China (English)
ZHU Zhen-He
2003-01-01
Some falsehoods of the so-called double-wave theory (DWT) are pointed out. The logic and the origin of the DWT, and three of the four fundamental hypotheses of DWT are criticized. It is expounded that the hypothesis of two wave functions is unreasonable, the hypothesized Hamiltonian differs from the actually used Hamiltonian, and the hypothesized expression of measured values or mean values of mechanical quantities is wrong and does not express the measured values or mean values at all.
Thermoelectric Power in the Double Exchange Model
Kim, Beom Hyun; Yu, Unjong; Kim, Kyoo; Min, B. I.
2007-01-01
Employing the Monte-Carlo method and the exact diagonalization, we have investigated the temperature dependence of the thermoelectric power (TEP) for the double exchange model in the dilute carrier concentration limit. We have found that the TEP follows the Heikes formula in the high temperature regime, whereas, in the intermediate temperature regime, the TEP is suppressed by the exchange coupling between itinerant electrons and local spins. In the low temperature regime, the TEP exhibits an ...
Double electron capture searches in $^{74}$Se
Lehnert, B; Degering, D; Sommer, D; Wagner, L; Zuber, K
2016-01-01
A search for various double electron capture modes of $^{74}$Se has been performed using an ultralow background Ge-detector in the Felsenkeller laboratory, Germany. Especially for the potentially resonant transition into the 1204.2 keV excited state of $^{74}$Ge a lower half-life limit of $0.70\\cdot 10^{19}$ yr (90% credibility) has been obtained. Serious concerns are raised about the validity of obtained $^{74}$Se limits in some recent publications.
Academic knowing in/through double perspectives
Directory of Open Access Journals (Sweden)
Margareta Melin
2015-12-01
Full Text Available This article explores the cultures and learning practices of four academic schools with an expressed wish to bridge the gap between traditional academic and arts or journalistic practices. Pierre Bourdieu, the French sociologist, termed them allodoxic, in that they challenge the traditional academic way of thinking and doing. Results from two research projects, spanning over 5 years, employing a multitude of methods, have been used in this article. The results show that these challenging bridging attempts create conflictual cultures. First, faculties with different backgrounds are employed and they bring with them their respective habitus and doxa (Bourdieu, which is manifested in their different epistemologies, doxas. Despite a strong will to work interdisciplinarily, conflicts (destructive arise particularly around epistemological and pedagogic issues. Second, I show that students at these schools have had double-perspective learning, through theoretical and practice-based methods, despite little help from their lecturers who have high ideals but little actual knowledge themselves of working in/through a double perspective. In many cases, through trial-and-error processes, students have appropriated embodied knowledge of a double perspective, which has given them surplus value when compared with learning through only traditional academic learning practices. It gives reflexive insights and understandings as well as transferrable skills highly useful in professional life. I finally argue that allodoxic conflictual cultures actually construct new ways of knowing through continuous discussions and meetings between faculties with different competences.
Fragmentation in DNA double-strand breaks
International Nuclear Information System (INIS)
DNA double strand breaks are important lesions induced by irradiations. Random breakage model or quantification supported by this concept is suitable to analyze DNA double strand break data induced by low LET radiation, but deviation from random breakage model is more evident in high LET radiation data analysis. In this work we develop a new method, statistical fragmentation model, to analyze the fragmentation process of DNA double strand breaks. After charged particles enter the biological cell, they produce ionizations along their tracks, and transfer their energies to the cells and break the cellular DNA strands into fragments. The probable distribution of the fragments is obtained under the condition in which the entropy is maximum. Under the approximation E≅E0 + E1l + E2l2, the distribution functions are obtained as exp(αl + βl2). There are two components, the one proportional to exp(βl2), mainly contributes to the low mass fragment yields, the other component, proportional to exp(αl), decreases slowly as the mass of the fragments increases. Numerical solution of the constraint equations provides parameters α and β. Experimental data, especially when the energy deposition is higher, support the statistical fragmentation model. (authors)
Visual mislocalization during double-step saccades
Directory of Open Access Journals (Sweden)
Eckart Zimmermann
2015-10-01
Full Text Available Visual objects presented briefly at the time of saccade onset appear compressed toward the saccade target. Compression strength depends on the presentation of a visual saccade target signal and is strongly reduced during the second saccade of a double-step saccade sequence (Zimmermann et al., 2014; 2014. Here, I tested whether perisaccadic compression is linked to saccade planning by contrasting two double-step paradigms. In the same-direction double-step paradigm, subjects were required to perform two rightward 10° saccades successively. At various times around execution of the saccade sequence a probe dot was briefly flashed. Subjects had to localize the position of the probe dot after they had completed both saccades. I found compression of visual space only at the time of the first but not at the time of the second saccade. In the reverse-direction paradigm, subjects performed first a rightward 10° saccade followed by a leftward 10° saccade back to initial fixation. In this paradigm compression was found in similar magnitude during both saccades. Analysis of the saccade parameters did not reveal indications of saccade sequence preplanning in this paradigm. I therefore conclude that saccade planning, rather than saccade execution factors, is involved in perisaccadic compression.
Perturbative quantum gravity in double field theory
Boels, Rutger H.; Horst, Christoph
2016-04-01
We study perturbative general relativity with a two-form and a dilaton using the double field theory formulation which features explicit index factorisation at the Lagrangian level. Explicit checks to known tree level results are performed. In a natural covariant gauge a ghost-like scalar which contributes even at tree level is shown to decouple consistently as required by perturbative unitarity. In addition, a lightcone gauge is explored which bypasses the problem altogether. Using this gauge to study BCFW on-shell recursion, we can show that most of the D-dimensional tree level S-matrix of the theory, including all pure graviton scattering amplitudes, is reproduced by the double field theory. More generally, we argue that the integrand may be reconstructed from its single cuts and provide limited evidence for off-shell cancellations in the Feynman graphs. As a straightforward application of the developed technology double field theory-like expressions for four field string corrections are derived.
Double-Difference Tomography for Sequestration MVA
Energy Technology Data Exchange (ETDEWEB)
Westman, Erik
2008-12-31
Analysis of synthetic data was performed to determine the most cost-effective tomographic monitoring system for a geologic carbon sequestration injection site. Double-difference tomographic inversion was performed on 125 synthetic data sets: five stages of CO2 plume growth, five seismic event regions, and five geophone arrays. Each resulting velocity model was compared quantitatively to its respective synthetic velocity model to determine an accuracy value. The results were examined to determine a relationship between cost and accuracy in monitoring, verification, and accounting applications using double-difference tomography. The geophone arrays with widely-varying geophone locations, both laterally and vertically, performed best. Additionally, double difference seismic tomography was performed using travel time data from a carbon sequestration site at the Aneth oil field in southeast Utah as part of a Department of Energy initiative on monitoring, verification, and accounting (MVA) of sequestered CO2. A total of 1,211 seismic events were recorded from a borehole array consisting of 22 geophones. Artificial velocity models were created to determine the ease with which different CO2 plume locations and sizes can be detected. Most likely because of the poor geophone arrangement, a low velocity zone in the Desert Creek reservoir can only be detected when regions of test site containing the highest ray path coverage are considered. MVA accuracy and precision may be improved through the use of a receiver array that provides more comprehensive ray path coverage.
Mechanical response of biopolymer double networks
Carroll, Joshua; Das, Moumita
We investigate a double network model of articular cartilage (AC) and characterize its equilibrium mechanical response. AC has very few cells and the extracellular matrix mainly determines its mechanical response. This matrix can be thought of as a double polymer network made of collagen and aggrecan. The collagen fibers are stiff and resist tension and compression forces, while aggrecans are flexible and control swelling and hydration. We construct a microscopic model made of two interconnected disordered polymer networks, with fiber elasticity chosen to qualitatively mimic the experimental system. We study the collective mechanical response of this double network as a function of the concentration and stiffness of the individual components as well as the strength of the connection between them using rigidity percolation theory. Our results may provide a better understanding of mechanisms underlying the mechanical resilience of AC, and more broadly may also lead to new perspectives on the mechanical response of multicomponent soft materials. This work was partially supported by a Cottrell College Science Award.
Organic doping of rotated double layer graphene
George, Lijin; Jaiswal, Manu
2016-05-01
Charge transfer techniques have been extensively used as knobs to tune electronic properties of two- dimensional systems, such as, for the modulation of conductivity mobility of single layer graphene and for opening the bandgap in bilayer graphene. The charge injected into the graphene layer shifts the Fermi level away from the minimum density of states point (Dirac point). In this work, we study charge transfer in rotated double-layer graphene achieved by the use of organic dopant, Tetracyanoquinodimethane. Naturally occurring bilayer graphene has a well-defined A-B stacking whereas in rotated double-layer the two graphene layers are randomly stacked with different rotational angles. This rotation is expected to significantly alter the interlayer interaction. Double-layer samples are prepared using layer-by-layer assembly of chemical vapor deposited single-layer graphene and they are identified by characteristic resonance in the Raman spectrum. The charge transfer and distribution of charges between the two graphene layers is studied using Raman spectroscopy and the results are compared with that for single-layer and A-B stacked bilayer graphene doped under identical conditions.
A background free double beta decay experiment
Giomataris, Ioannis
2010-01-01
We present a new detection scheme for rejecting backgrounds in neutrino less double beta decay experiments. It relies on the detection of Cherenkov light emitted by electrons in the MeV region. The momentum threshold is tuned to reach a good discrimination between background and good events. We consider many detector concepts and a range of target materials. The most promising is a high-pressure 136Xe emitter for which the required energy threshold is easily adjusted. Combination of this concept and a high pressure Time Projection Chamber could provide an optimal solution. A simple and low cost effective solution is to use the Spherical Proportional Counter that provides two delayed signals from ionization and Cherenkov light. In solid-state double beta decay emitters, because of their higher density, the considered process is out of energy range. An alternative solution could be the development of double decay emitters with lower density by using for instance the aerogel technique. It is surprising that a te...
Simulation in double-beta decay experiments
International Nuclear Information System (INIS)
A detailed understanding of background radiation sources is a key to interpretation and enhanced sensitivity of double-beta decay experiments. Improvement of several techniques will be discussed. An implementation of the EGS4 code was developed to improve the accuracy of detector simulations, in particular for a 100Mo double-beta decay experiment. The efficiency modification due to the angular dependence of the 539 keV - 590 keV gamma-ray coincidence was successfully determined. The success of the 100Mo effort led to the modeling of uranium-thorium backgrounds found in an electroformed copper shield built for a 76Ge experiment. The large copper mass increased our sensitivity to contaminants present in copper produced this way, and led to changes in our cryostat electroforming technique. The original goal was the determination of the 210Pb content of the 450 year old lead shield previously used in 71Ge two-neutrino double-beta decay measurements. The results pertaining to low background materials and fabrication techniques will also be discussed
DNA-like double helix formed by peptide nucleic acid
DEFF Research Database (Denmark)
Wittung, P; Nielsen, Peter E.; Buchardt, O; Egholm, M; Nordén, B
1994-01-01
Although the importance of the nucleobases in the DNA double helix is well understood, the evolutionary significance of the deoxyribose phosphate backbone and the contribution of this chemical entity to the overall helical structure and stability of the double helix is not so clear. Peptide nucleic...... of double helical DNA-like structures in solution....
Testing Intelligently Includes Double-Checking Wechsler IQ Scores
Kuentzel, Jeffrey G.; Hetterscheidt, Lesley A.; Barnett, Douglas
2011-01-01
The rigors of standardized testing make for numerous opportunities for examiner error, including simple computational mistakes in scoring. Although experts recommend that test scoring be double-checked, the extent to which independent double-checking would reduce scoring errors is not known. A double-checking procedure was established at a…
Studies of double parton scattering with the ATLAS detector
Gueta, Orel; The ATLAS collaboration
2016-01-01
The contributions of double and multiple parton scattering are sizable in many physics processes at the LHC, especially in the region of low particle transverse momenta. Studies of double parton scattering using various final states are presented along with measurements of the effective cross section, exploiting the different kinematic configurations of events with the double parton and single parton scattering.
26 CFR 509.120 - Double taxation claims.
2010-04-01
... 26 Internal Revenue 19 2010-04-01 2010-04-01 false Double taxation claims. 509.120 Section 509.120... CONVENTIONS SWITZERLAND General Income Tax § 509.120 Double taxation claims. (a) General. Under Article XVII... United States or Switzerland has resulted, or will result, in double taxation contrary to the...
A novel beam width doubling double crystal monochromator -some preliminary findings
International Nuclear Information System (INIS)
The maximum useable beam width at the Biomedical Imaging and Therapy (BMIT) beamline at the Canadian Light Source (CLS) is suitable for most imaging applications. But access to a wider beam would benefit many programs especially computed tomography where the beam width defines the largest sample that can be imaged. A double crystal bent Laue monochromator capable of doubling the width of the incident beam is proposed; this is possible by taking advantage of symmetric off-axis, or skew reflections in the crystals. A preliminary experiment to establish proof of concept for this design has been completed using a double crystal unbent Laue system. Results are presented showing the beam width doubling from 28.3mm to 56.6mm and the effect of the skew reflections on the monochromaticity of the exit beam. Further work on this monochromator will include an investigation into the choice of reflections, a study of the effect on the change in energy across the exit beam, the development of strategies to minimize the effect of the beam overlap region downstream from the monochromator and the development of an alignment process for the double crystal bent Laue system.
Two experiments on the wave/particle concept - towards a double-double-slit experiment
International Nuclear Information System (INIS)
Full text: We present two experiments on single- and two-particle interference. In the single-photon interference experiment, photons from a spontaneous parametric down-conversion (SPDC) source are send through a double slit. An interference pattern is built up frame by frame from shots obtained with an EMCCD camera behind the slit. Each frame contains on average less than one photon, thus demonstrating true singlephoton sensitivity of the camera. The build-up of the interference pattern nicely demonstrates the concept of wave-particle duality. In a next step, we describe the Heisenberg's lens experiment and present the conditions required to analyze and investigate the spatial correlations of momentum entangled photons produced by SPDC. The occurrence of double-slit interference now depends on the experimental arrangement for the second photon of the pair, for example: interference can only occur if the second photon is also passing a double slit. We present an analysis of such a double-double-slit experiment. (author)
Multifrequency study of a double-double radio galaxy J1706+4340
Marecki, A; Machalski, J
2016-01-01
We report the outcome of multifrequency radio observations of a double-double radio source J1706+4340 carried out with the Very Large Array and Giant Metrewave Radio Telescope. After supplementing our own data with those available in the literature, we collected a considerable set of radio measurements covering the range from 74 to 8460 MHz. This has enabled us to perform a comprehensive review of physical properties of the source and its dynamical evolution analysis. In particular, we found that, while the age of the large-scale outer lobes is in the range 260-300 Myr, the renewal of the jet activity, which is directly responsible for the double-double structure, took place only about 12 Myr ago after about 27-Myr long period of quiescence. Another important property of J1706+4340 we found is that the injection spectral indices and the jet powers for the inner and the outer doubles are very similar. This implies that it is the spin of the supermassive black hole rather than e.g. an instability of the accreti...
Design studies for the Double Chooz trigger
International Nuclear Information System (INIS)
The main characteristic of the neutrino mixing effect is assumed to be the coupling between the flavor and the mass eigenstates. Three mixing angles (θ12, θ23, θ13) are describing the magnitude of this effect. Still unknown, θ13 is considered very small, based on the measurement done by the CHOOZ experiment. A leading experiment will be Double Chooz, placed in the Ardennes region, on the same site as used by CHOOZ. The Double Chooz goal is the exploration of ∝80% from the currently allowed θ13 region, by searching the disappearance of reactor antineutrinos. Double Chooz will use two similar detectors, located at different distances from the reactor cores: a near one at ∝150 m where no oscillations are expected and a far one at 1.05 km distance, close to the first minimum of the survival probability function. The measurement foresees a precise comparison of neutrino rates and spectra between both detectors. The detection mechanism is based on the inverse β-decay. The Double Chooz detectors have been designed to minimize the rate of random background. In a simplified view, two optically separated regions are considered. The target, filled with Gd-doped liquid scintillator, is the main antineutrino interaction volume. Surrounding the target, the inner veto region aims to tag the cosmogenic muon background which hits the detector. Both regions are viewed by photomultipliers. The Double Chooz trigger system has to be highly efficient for antineutrino events as well as for several types of background. The trigger analyzes discriminated signals from the central region and the inner veto photomultipliers. The trigger logic is fully programmable and can combine the input signals. The trigger conditions are based on the total energy released in event and on the PMT groups multiplicity. For redundancy, two independent trigger boards will be used for the central region, each of them receiving signals from half of the photomultipliers. A third trigger board will
Design studies for the Double Chooz trigger
Energy Technology Data Exchange (ETDEWEB)
Cucoanes, Andi Sebastian
2009-07-24
The main characteristic of the neutrino mixing effect is assumed to be the coupling between the flavor and the mass eigenstates. Three mixing angles ({theta}{sub 12}, {theta}{sub 23}, {theta}{sub 13}) are describing the magnitude of this effect. Still unknown, {theta}{sub 13} is considered very small, based on the measurement done by the CHOOZ experiment. A leading experiment will be Double Chooz, placed in the Ardennes region, on the same site as used by CHOOZ. The Double Chooz goal is the exploration of {proportional_to}80% from the currently allowed {theta}{sub 13} region, by searching the disappearance of reactor antineutrinos. Double Chooz will use two similar detectors, located at different distances from the reactor cores: a near one at {proportional_to}150 m where no oscillations are expected and a far one at 1.05 km distance, close to the first minimum of the survival probability function. The measurement foresees a precise comparison of neutrino rates and spectra between both detectors. The detection mechanism is based on the inverse {beta}-decay. The Double Chooz detectors have been designed to minimize the rate of random background. In a simplified view, two optically separated regions are considered. The target, filled with Gd-doped liquid scintillator, is the main antineutrino interaction volume. Surrounding the target, the inner veto region aims to tag the cosmogenic muon background which hits the detector. Both regions are viewed by photomultipliers. The Double Chooz trigger system has to be highly efficient for antineutrino events as well as for several types of background. The trigger analyzes discriminated signals from the central region and the inner veto photomultipliers. The trigger logic is fully programmable and can combine the input signals. The trigger conditions are based on the total energy released in event and on the PMT groups multiplicity. For redundancy, two independent trigger boards will be used for the central region, each of
The Dynamics of Radio Galaxies and Double-Double Radio Galaxies
Konar, C; Hardcastle, M J; Croston, J H; Nandi, S; Saikia, D J; Machalski, J
2013-01-01
Relativistic and magnetised plasma ejected by radio loud AGNs through jets form the diffuse lobes of radio galaxies. The radiating particles (electron/electron-positron) in lobes emit in radio via the synchrotron process and X-ray via inverse-Compton scattering of cosmic microwave background photons. The thermal environment around radio galaxies emits X-rays via the thermal bremsstrahlung process. By combining information from these processes we can measure physical conditions in and around the radio lobes and thus study the dynamics of radio galaxies, including double-double radio galaxies.
Double orifice mitral valve: A case report
Directory of Open Access Journals (Sweden)
Musić Ljilja
2016-01-01
Full Text Available Introduction. Double orifice mitrol valve (DOMV is a very rare congenital heart defect. Case report. We reported 20-year-old male referred to our center due to evaluation of his cardiologic status. He was operated on shortly after birth for a tracheoesophageal fistula. Accidentally, echocardiography examination at the age of 4 years revealed double orifice mitral valve (DOMV without the presence of mitral regurgitation, as well as mitral stenosis, with normal dimensions of all cardiac chambers. The patient was asymptomatic, even more he was a kick boxer. His physical finding was normal. Electrocardiography showed regular sinus rhythm, incomplete right bundle branch block. Transthoracic echocardiography (TTE examination revealed the normal size of the left atrial, mitral leaflets were slightly more redundant. The left and right heart chambers, aorta, tricuspid valve and pulmonary artery valve were normal. During TTE examination on a short axis view two asymmetric mitral orifices were seen as a double mitral orifice through which we registered normal flow, without regurgitation and mitral stenosis. Transesophageal echocardiography (TEE examination from the transgastric view at the level of mitral valve, showed 2 single asymmetric mitral orifices separated by fibrous tissue, mitral leaflet with a separate insertion of hordes for each orifice. Conclusion. The presented patient with DOMV is the only one recognized in our country. The case is interesting because during 16-year a follow-up period there were no functional changes despite the fact that he performed very demanded sport activities. This is very important because there is no information in the literature about that.
Double-oblique cine cardiac MR imaging
International Nuclear Information System (INIS)
A study has been performed analyzing the contrast between the blood pool and myocardium on double oblique long- and short-axis cine MR images using gradient echo fast imaging with steady precession and fast low-angle shot sequences. Inflow of unsaturated spins dominates the contrast behavior of short-axis images. With long-axis imaging, suboptimal contrast is seen in peak systole and early diastole due to partial saturation of spins in the imaging section and anatomic considerations at small ventricular volumes. The effects of echo time, flip angle, motion compensation, and spatial presaturation on the contrast between the blood pool and myocardium are discussed
Probabilistic properties of the continuous double auction
Czech Academy of Sciences Publication Activity Database
Šmíd, Martin
2012-01-01
Roč. 48, č. 1 (2012), s. 50-82. ISSN 0023-5954 R&D Projects: GA ČR GAP402/10/1610; GA ČR GAP402/10/0956; GA ČR(CZ) GA402/06/1417 Institutional research plan: CEZ:AV0Z10750506 Keywords : continuous double auction * limit order market * distribution Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.619, year: 2012 http://library.utia.cas.cz/separaty/2012/E/smid-0372702.pdf
Double-Stranded RNA Resists Condensation
Li, Li; Pabit, Suzette A.; Meisburger, Steve P.; Pollack, Lois
2011-03-01
Much attention has been focused on DNA condensation because of its fundamental biological importance. The recent discovery of new roles for RNA duplexes demands efficient packaging of double-stranded RNA for therapeutics. Here we report measurements of short DNA and RNA duplexes in the presence of trivalent ions. Under conditions where UV spectroscopy indicates condensation of DNA duplexes into (insoluble) precipitates, RNA duplexes remain soluble. Small angle x-ray scattering results suggest that the differing surface topologies of RNA and DNA may be crucial in generating the attractive forces that result in precipitation.
Standard Model as a Double Field Theory
Choi, Kang-Sin; Park, Jeong-Hyuck
2015-01-01
We show that, without any extra physical degree introduced, the Standard Model can be readily reformulated as a Double Field Theory. Consequently, the Standard Model can couple to an arbitrary stringy gravitational background in an $\\mathbf{O}(4,4)$ T-duality covariant manner and manifest two independent local Lorentz symmetries, $\\mathbf{Spin}(1,3)\\times\\mathbf{Spin}(3,1)$. While the diagonal gauge fixing of the twofold spin groups leads to the conventional formulation on the flat Minkowskia...
Solid phase double-antibody radioimmunoassay procedure
International Nuclear Information System (INIS)
The present invention is concerned with the radioimmunoassay (RIA) procedure for assaying body fluid content of an antigenic substance which may either be an antigen itself or a hapten capable of being converted, such as by means of reaction with a protein, to an antigenic material. The present invention is concerned with a novel and improved modification of a double-antibody RIA technique in which there is a first antibody that is specific to the antigenic substance suspected to be present in a body fluid from which the assay is intended. The second antibody, however, is not specific to the antigenic substance or analyte, but is an antibody against the first antibody
Inviscid double wake model for stalled airfoils
DEFF Research Database (Denmark)
Marion, Lucas; Ramos García, Néstor; Sørensen, Jens Nørkær
2014-01-01
An inviscid double wake model based on a steady two-dimensional panel method has been developed to predict aerodynamic loads of wind turbine airfoils in the deep stall region. The separated flow is modelled using two constant vorticity sheets which are released at the trailing edge and at the...... separation point. A calibration of the code through comparison with experiments has been performed using one set of airfoils. A second set of airfoils has been used for the validation of the calibrated model. Predicted aerodynamic forces for a wide range of angles of attack (0 to 90 deg) are in overall good...
Double emulsion in a compound droplet
Terwagne, Denis; Gilet, Tristan; Vandewalle, Nicolas; Dorbolo, Stéphane
2010-01-01
A compound drop is made of a millimetric water drop encapsulated in an oil shell. They are obtained by merging one drop of each component (water and oil). Afterwards, they are laid on a high viscosity oil bath which is vertically vibrated. When the forcing acceleration is higher than a given threshold Γth, compound drops can bounce on the surface. We show that above a second threshold Γe > Γth some oil contained in the shell enters in the inner water droplet forming a stable double emulsion.
Double photoionization of He at intermediate energies
International Nuclear Information System (INIS)
The ratio of double-to-single ionization of He has been measured between 280 and 1210 eV to investigate its behavior in this partially unexplored region. These measurements, compared with the most recent theories of Pan and Kelly (private communication) and of Hino, show the importance of including not only ground state but also final state correlations, in contrast to the high-energy behavior discussed by Dalgarno and Sadeghpour where consideration of final-state correlations proves inessential. The author's intermediate-energy results also appear to indicate the importance of including higher-order effects in the theory
Neutrinoless double beta decay search with SNO+
Lozza V.
2014-01-01
The SNO+ experiment is the follow up of SNO. The detector is located 2 km underground in the Vale Canada Ltd.’s Creighton Mine near Sudbury, Ontario, Canada. The active volume of the detector consists of 780 tonnes of Linear Alkyl Benzene (LAB) in an acrylic vessel of 12 m diameter, surrounded by about 9500 PMTs. The main goal of the SNO+ experiment is the search for neutrinoless double beta decay of 130Te. With an initial loading of 0.3% of natural tellurium (nearly 800 kg of 130Te), it is e...
Charakterisierung der Double Chooz–Photomultiplier
Huth, L.
2012-01-01
The Double Chooz (DC) experiment is a reactor electron anti-neutrino oscillation experiment, which is located in France. The main goal of DC is to measure the last unknown neutrino mixing angle θ13 of the transformation matrix UPNMS using electron anti-neutrinos, produced by two identical nuclear reactors. The detection of an electron anti-neutrino takes place via light emission produced in the inverse β-decay. This light is detected by photomultipliers. The electronics in the base of the pho...
Treatment of an Aortic Traumatic Double Rupture
Directory of Open Access Journals (Sweden)
Attinà Domenico
2015-03-01
Full Text Available Traumatic thoracic aortic rupture is a life-threatening condition; aortic isthmus is the most common site of rupture, but in rare cases traumatic injury can localize elsewhere, such as at aortic arch or at the level of the diaphragm. In the past few years, endovascular treatment of traumatic aortic injury became a safe procedure, with lower mortality and complication, if compared with open surgery. We report a case of a 40-year-old-man admitted to emergency department after a violent car crash in which an aortic traumatic double rupture was successfully treated with two endovascular stent-grafts coverage.
The high sensitivity double beta spectrometer TGV
Briancon, Ch.; Brudanin, V. B.; Egorov, V. G.; Janout, Z.; Koníček, J.; Kovalík, A.; Kovalenko, V. E.; Kubašta, J.; Pospíšil, S.; Revenko, A. V.; Rukhadze, N. I.; Salamatin, A. V.; Sandukovsky, V. G.; Štekl, I.; Timkin, V. V.; Tsupko-Sitnikov, V. V.; Vorobel, V.; Vylov, Ts.
1996-02-01
A high sensitivity double beta spectrometer TGV (Telescope Germanium Vertical) has been developed. It is based on 16 HPGe detectors of volume 1200 × 6 mm 3 each in the same cryostat. The TGV spectrometer was proposed for the study of ultrarare nuclear processes (e.g. 2νββ, 0νββ, 2νEC/EC). Details of the TGV spectrometer construction are described, the principles of background suppression, the results of Monte Carlo simulations and the results of test background measurements (in Dubna and Modane underground laboratory) are provided.
The high sensitivity double beta spectrometer TGV
International Nuclear Information System (INIS)
A high sensitivity double beta spectrometer TGV (Telescope Germanium Vertical) has been developed. It is based on 16 HPGe detectors of volume 1200 x 6 mm3 each in the same cryostat. The TGV spectrometer was proposed for the study of ultrarare nuclear processes (e.g. 2νββ, 0νββ, 2νEC/EC). Details of the TGV spectrometer construction are described, the principles of background suppression, the results of Monte Carlo simulations and the results of test background measurements (in Dubna and Modane underground laboratory) are provided. (orig.)
Tracking speckle displacement by double Kalman filtering
Institute of Scientific and Technical Information of China (English)
Donghui Li; Li Guo
2006-01-01
@@ A tracking technique using two sequentially-connected Kalman filter for tracking laser speckle displacement is presented. One Kalman filter tracks temporal speckle displacement, while another Kalman filter tracks spatial speckle displacement. The temporal Kalman filter provides a prior for the spatial Kalman filter, and the spatial Kalman filter provides measurements for the temporal Kalman filter. The contribution of a prior to estimations of the spatial Kalman filter is analyzed. An optical analysis system was set up to verify the double-Kalman-filter tracker's ability of tracking laser speckle's constant displacement.
Synthesis of 15 N double labelled urea
International Nuclear Information System (INIS)
Synthesis of double 15 N labelled urea by reacting 15 N - ammonia with elemental sulfur and carbon monoxide in a pressure vessel is presented. 15 NH3 was produced by H15 NO3 reduction with Dewarda alloy in alkaline solution, or by nitric monoxide reduction with hydrogen on metallic manganese. An average yield of 85% tacking into account 15 N - urea and 15 N ammonium sulfate, produced in the same time, and 99% urea purity (checked by I.R. spectroscopy and mass spectrometry) were obtained. (authors)
Many worlds interpretation for double slit experiment
Yun, Zinkoo
2014-01-01
As is well known, the double slit experiment contains every key concepts of quantum mechanics such as phase effect, probability wave, quantum interference, quantum superposition. In this article, I will clarify the meaning of quantum superposition in terms of phase effect between states. After applying standard quantum theory, it leads to serious questions about the unitary process of an isolated system. It implies that non collapsing interpretations including many worlds may not be justified. This also could explain that there is no such boundary between classical and quantum domains.
Potential pitfalls of a double PCL sign
Energy Technology Data Exchange (ETDEWEB)
Venkatanarasimha, Nanda [Derriford Hospital, Department of Radiology, Plymouth (United Kingdom); Kamath, A. [Royal Gwent Hospital, Department of Accident and Emergency, Newport (United Kingdom); Mukherjee, K.; Kamath, S. [University Hospital of Wales, Department of Radiology, Cardiff (United Kingdom)
2009-08-15
The double posterior cruciate ligament (PCL) sign is seen on a midline sagittal MR image of the knee as a low-signal-intensity linear band paralleling the antero-inferior part of the PCL. Although the sign has a high specificity for a displaced bucket-handle tear of the medial meniscus, it can be mimicked by several normal and abnormal structures in the intercondylar region. Familiarity with these variants and identifying the other features supportive of meniscal injury will help to make a confident diagnosis of bucket-handle tear of the medial meniscus. (orig.)
NEUTRINOLESS DOUBLE BETA DECAY: AN EXTREME CHALLENGE
Directory of Open Access Journals (Sweden)
Fernando Ferroni
2013-12-01
Full Text Available Neutrino-less Double Beta Decay is the only known way to possibly resolve the nature of neutrino mass. The chances to cover the mass region predicted by the inverted hierarchy require a step forward in detector capability. A possibility is to make use of scintillating bolometers. These devices shall have a great power in distinguishing signals from alfa particles from those induced by electrons. This feature might lead to an almost background-free experiment. Here the Lucifer concept will be introduced and the prospects related to this project will be discussed.
Resonant double loop antenna development at ORNL
International Nuclear Information System (INIS)
As part of the development of ion cyclotron resonant heating (ICRH) systems for fusion research, Oak Ridge National Laboratory (ORNL) has built resonant double loop (RDL) antennas for the Tokamak Fusion Test Reactor (TFTR) (Princeton Plasma Physics Laboratory, Princeton, NJ, US) and Tore Supra (Centre d'Etudes Nucleaire, Cadarache, France). Each antenna has been designed to deliver 4 MW of power. The electrical circuit and the mechanical philosophy employed are the same for both antennas, but different operating environments lead to substantial differences in the designs of specific components. A description and a comparison of the technologies developed in the two designs are presented. 5 refs., 4 figs., 1 tab
Double-balloon endoscopy: Who needs it?
DEFF Research Database (Denmark)
Hendel, J.W.; Vilmann, P.; Jensen, T.
2008-01-01
Objective. Double-balloon endoscopy (DBE) made the small bowel accessible to inspection and therapy in its entirety. However, DBE is a time-consuming procedure that requires a highly skilled endoscopist, several nurses and - more often than not - anesthesiological support. This makes the selection...... of patients for DBE a pivotal point. The mainstay of this screening examination of the small bowel is capsule endoscopy (CE). The aim of this study was to describe the results of this screening procedure and the subsequent DBE in patients with suspected mid-gastrointestinal bleeding (MGIB). Material...
Double-mirror peripheral vitrectomy lens.
Ohji, M; Tano, Y
1995-11-01
Many surgeons use prism lenses to see the periphery of the fundus during vitrectomy; however, chromatic aberrations in higher-power prismatic lenses cause blurring of the peripheral image. For better visualization of the periphery of the fundus, we developed a new contact lens, the double-mirror peripheral vitrectomy lens. The new lens is a quartz cylinder with two mirrors, and it provides a crisp, clear, upright image of much more of the peripheral fundus than is visible through conventional prism lenses. The new lens also provides a wider area of view than conventional prism lenses. PMID:7487611
1919 + 742 - A large double radio source
Strom, R. G.; Eckart, A.; Biermann, P.
1985-10-01
A 49-cm map of the source 1919 + 742 (previously catalogued as 4C74.24 and NB74.26) shows it to be a large double. Although the optical identification is unclear, there are several candidate objects near the source centroid which appear to be members of a small group of galaxies. The absence of bright identification candidates argues for a moderately distant, and hence intrinsically large (750 kpc overall size for z = 0.1) object. The spectrum between 80 and 600 MHz is determined, some intrinsic properties are derived, and these are briefly discussed in the context of other large sources.
Bound States of Double Flavor Hyperons
Froemel, F; Riska, D O
2005-01-01
Several realistic phenomenological nucleon-nucleon interaction models are employed to investigate the possibility of bound deuteron-like states of such heavy flavor hyperons and nucleons, for which the interaction between the light flavor quark components is expected to be the most significant interaction. The results indicate that deuteron-like bound states are likely to form between nucleons and the $\\Xi_c^{'}$ and $\\Xi_{cc}$ charm hyperons as well as between $\\Xi$ hyperons and double-charm hyperons. Bound states between two $\\Sigma_c$ hyperons are also likely. In the case of beauty hyperons the corresponding states are likely to be deeply bound.
A Limit Theorem for Double Arrays
Rosalsky, Andrew; Teicher, Henry
1981-01-01
The main result establishes that row sums $S_n$ of a double array of rowwise independent, infinitesimal (or merely uniformly asymptotically constant) random variables satisfying $\\lim \\sup |S_n - M_n| \\leq M_0 < \\infty$ a.c. (for some choice of constants $M_n$), obey a weak law of large numbers, i.e., $S_n - \\operatorname{med} S_n$ converges in probability to 0. No moment assumptions are imposed on the individual summands and zero-one laws are unavailable. As special cases, a new result for w...
Double-negative flexural acoustic metamaterial
International Nuclear Information System (INIS)
We present an acoustic metamaterial for flexural waves with both negative density and elastic modulus. By means of an analytical lumped-element approach, we introduce a combination of resonant elements on the surface of a plate. Following on from experimental demonstrations and theoretical work, negative density is achieved by introducing elements such as stubs that involve normal-force interactions, whereas negative modulus is achieved by introducing new types of resonant element that involve lateral forces and rotational inertia. Our approach therefore opens the way for the realization of double-negative acoustic meta-plates to control flexural waves. Applications include cloaking and filtering. (paper)
Non-sequential double ionization of molecules
Prauzner-Bechcicki, J S; Eckhardt, B; Zakrzewski, J; Prauzner-Bechcicki, Jakub S.; Sacha, Krzysztof; Eckhardt, Bruno; Zakrzewski, Jakub
2004-01-01
Double ionization of diatomic molecules by short linearly polarized laser pulses is analyzed. We consider the final stage of the ionization process, that is the decay of a highly excited two electron molecule, which is formed after re-scattering. The saddles of the effective adiabatic potential energy close to which simultaneous escape of electrons takes place are identified. Numerical simulations of the ionization of molecules show that the process can be dominated by either sequential or non-sequential events. In order to increase the ratio of non-sequential to sequential ionizations very short laser pulses should be applied.
DOUBLE-DIP RECESSION AND POLICY OPTIONS
Miroljub Labus
2012-01-01
It is reasonable to expect the Serbian economy to decline up to -1% in 2012. A double-dip recession is inevitable. Lessons from the previous recession in 2009 suggest that an expansionary fiscal policy has clear limits, and that any misalignment of economic policies might be highly costly.This time, in addition to a recession and lack of policy coordination, the Serbian economy is exposed to the political risk associated with new elections. All of these risks deserve proper attention. In this...
The double formation of primordial black holes
International Nuclear Information System (INIS)
Primordial black holes (PBHs) are a useful tool in cosmology to probe primordial inhomogeneities on small scales that reenter the Hubble radius during the radiation dominated epoch. In this paper, a phenomenon we call the double formation of PBHs, described below, is explored. Suppose there exists a highly perturbed region which will collapse to form a PBH after the horizon crossing of this region, and farther that this region is superposed on a perturbed region of a much larger scale, which also collapses upon its reentry. One then expects the collapse of the central smaller region at the time of the crossing of this region, followed by another collapse of the larger perturbation at the time of its respective crossing. The smaller PBH, formed earlier, should be swallowed in the second collapse leading to a single larger PBH as the final state. This paper reports the first direct numerical confirmation of such double PBH formation. Related to this, we also discuss the effects of high-frequency modes on the formation of PBHs, which turn out to facilitate the formation of PBHs, thereby potentially increasing the abundance of PBHs by several orders of magnitude
Statistical theory of the continuous double auction
Smith, Eric; Doyne Farmer, J.; Gillemot, László; Krishnamurthy, Supriya
2003-12-01
Most modern financial markets use a continuous double auction mechanism to store and match orders and facilitate trading. In this paper we develop a microscopic dynamical statistical model for the continuous double auction under the assumption of IID random order flow, and analyse it using simulation, dimensional analysis, and theoretical tools based on mean field approximations. The model makes testable predictions for basic properties of markets, such as price volatility, the depth of stored supply and demand versus price, the bid-ask spread, the price impact function, and the time and probability of filling orders. These predictions are based on properties of order flow and the limit order book, such as share volume of market and limit orders, cancellations, typical order size, and tick size. Because these quantities can all be measured directly there are no free parameters. We show that the order size, which can be cast as a non-dimensional granularity parameter, is in most cases a more significant determinant of market behaviour than tick size. We also provide an explanation for the observed highly concave nature of the price impact function. On a broader level, this work suggests how stochastic models based on zero intelligence agents may be useful to probe the structure of market institutions. Like the model of perfect rationality, a stochastic zero intelligence model can be used to make strong predictions based on a compact set of assumptions, even if these assumptions are not fully believable.
Neutrinoless double beta decay search with SNO+
Lozza, V.
2014-01-01
The SNO+ experiment is the follow up of SNO. The detector is located 2 km underground in the Vale Canada Ltd.'s Creighton Mine near Sudbury, Ontario, Canada. The active volume of the detector consists of 780 tonnes of Linear Alkyl Benzene (LAB) in an acrylic vessel of 12 m diameter, surrounded by about 9500 PMTs. The main goal of the SNO+ experiment is the search for neutrinoless double beta decay of 130Te. With an initial loading of 0.3% of natural tellurium (nearly 800 kg of 130Te), it is expected to reach a sensitivity on the effective Majorana neutrino mass of about 100 meV after several years of data taking. Designed as a general purpose neutrino experiment, other exciting physical goals can be explored, like the measurement of reactor neutrino oscillations and geo-neutrinos in a geologically-interesting location, watch of supernova neutrinos and studies of solar neutrinos. A first commissioning phase with water filled detector will start at the end of 2013, while the double beta decay phase will start in 2015.
The double formation of primordial black holes
Nakama, Tomohiro
2014-01-01
Primordial black holes (PBHs) are a useful tool in cosmology to probe primordial inhomogeneities on small scales that reenter the Hubble radius during the radiation dominated epoch. In this paper, a phenomenon we call the double formation of PBHs, described below, is explored. Suppose there exists a highly perturbed region which will collapse to form a PBH after the horizon crossing of this region, and farther that this region is superposed on much larger region, which also collapses upon reentry. One then expects the collapse of the central smaller region at the time of the crossing of this region, followed by another collapse of the larger perturbation at the time of its respective crossing. The smaller PBH, formed earlier, should be swallowed in the second collapse leading to a single larger PBH as the final state. This paper reports the first direct numerical confirmation of such double PBH formation. Related to this, we also discuss the effects of high-frequency modes on the formation of PBHs.
Double Retort System for Materials Compatibility Testing
Energy Technology Data Exchange (ETDEWEB)
V. Munne; EV Carelli
2006-02-23
With Naval Reactors (NR) approval of the Naval Reactors Prime Contractor Team (NRPCT) recommendation to develop a gas cooled reactor directly coupled to a Brayton power conversion system as the Space Nuclear Power Plant (SNPP) for Project Prometheus (References a and b) there was a need to investigate compatibility between the various materials to be used throughout the SNPP. Of particular interest was the transport of interstitial impurities from the nickel-base superalloys, which were leading candidates for most of the piping and turbine components to the refractory metal alloys planned for use in the reactor core. This kind of contamination has the potential to affect the lifetime of the core materials. This letter provides technical information regarding the assembly and operation of a double retort materials compatibility testing system and initial experimental results. The use of a double retort system to test materials compatibility through the transfer of impurities from a source to a sink material is described here. The system has independent temperature control for both materials and is far less complex than closed loops. The system is described in detail and the results of three experiments are presented.
Double Retort System for Materials Compatibility Testing
International Nuclear Information System (INIS)
With Naval Reactors (NR) approval of the Naval Reactors Prime Contractor Team (NRPCT) recommendation to develop a gas cooled reactor directly coupled to a Brayton power conversion system as the Space Nuclear Power Plant (SNPP) for Project Prometheus (References a and b) there was a need to investigate compatibility between the various materials to be used throughout the SNPP. Of particular interest was the transport of interstitial impurities from the nickel-base superalloys, which were leading candidates for most of the piping and turbine components to the refractory metal alloys planned for use in the reactor core. This kind of contamination has the potential to affect the lifetime of the core materials. This letter provides technical information regarding the assembly and operation of a double retort materials compatibility testing system and initial experimental results. The use of a double retort system to test materials compatibility through the transfer of impurities from a source to a sink material is described here. The system has independent temperature control for both materials and is far less complex than closed loops. The system is described in detail and the results of three experiments are presented
Exchange effects in double beta decay
International Nuclear Information System (INIS)
Over the past decade there has been very impressive progress in the laboratory study of double beta decay with very precise limits on 0-neutrino decay in /sup 76/Ge, the imminent prospect of the observation of 2-neutrino decay in /sup 100/Mo and the first laboratory observation of 2-neutrino decay in /sup 82/Se. For the last case, the laboratory rate is in essential agreement with geochemical results and in reasonable agreement with theoretical predictions based on a full shell model calculation. The motivation underlying the resurgence of interest in double beta decay is the hope that the observation of, or limits on the 0-neutrino mode will provide information about the nature of the neutrino. This clearly requires confidence in the nuclear matrix elements involved in the transition. The shell model calculations do not agree well with the geochemical values for /sup 130/Te, which has led to a spate of papers offering specific fixes for the problem. In this contribution we shall not comment on any of the specific nuclear calculations, rather we make some remarks which should be relevant to any model calculation. 11 refs., 1 tab
Color Constancy Using Double-Opponency.
Gao, Shao-Bing; Yang, Kai-Fu; Li, Chao-Yi; Li, Yong-Jie
2015-10-01
The double-opponent (DO) color-sensitive cells in the primary visual cortex (V1) of the human visual system (HVS) have long been recognized as the physiological basis of color constancy. In this work we propose a new color constancy model by imitating the functional properties of the HVS from the single-opponent (SO) cells in the retina to the DO cells in V1 and the possible neurons in the higher visual cortexes. The idea behind the proposed double-opponency based color constancy (DOCC) model originates from the substantial observation that the color distribution of the responses of DO cells to the color-biased images coincides well with the vector denoting the light source color. Then the illuminant color is easily estimated by pooling the responses of DO cells in separate channels in LMS space with the pooling mechanism of sum or max. Extensive evaluations on three commonly used datasets, including the test with the dataset dependent optimal parameters, as well as the intra- and inter-dataset cross validation, show that our physiologically inspired DOCC model can produce quite competitive results in comparison to the state-of-the-art approaches, but with a relative simple implementation and without requiring fine-tuning of the method for each different dataset. PMID:26353182
Double parton scattering at high energies
Szczurek, Antoni
2015-01-01
We discuss a few examples of rich newly developing field of double parton scattering. We start our presentation from production of two pairs of charm quark-antiquark and argue that it is the golden reaction to study the double parton scattering effects. In addition to the DPS we consider briefly also mechanism of single parton scattering and show that it gives much smaller contribution to the $c \\bar c c \\bar c$ final state. Next we discuss a perturbative parton-splitting mechanism which should be included in addition to the conventional DPS mechanism. We show that the presence of this mechanism unavoidably leads to collision energy and other kinematical variables dependence of so-called $\\sigma_{eff}$ parameter being extracted from different experiments. Next we briefly discuss production of four jets. We concentrate on estimation of the contribution of DPS for jets remote in rapidity. Understanding of this contribution is very important in the context of searches for BFKL effects known under the the name Mu...
Double unresolved approximations to multiparton scattering amplitudes
International Nuclear Information System (INIS)
We present approximations to tree-level multiparton scattering amplitudes which are appropriate when two partons are unresolved. These approximations are required for the analytic isolation of infrared singularities of n+2 parton scattering processes contributing to the next-to-next-to-leading order corrections to n jet cross sections. In each case the colour ordered matrix elements factorise and yield a function containing the singular factors multiplying the n-parton amplitudes. When the unresolved particles are colour unconnected, the approximations are simple products of the familiar eikonal and Altarelli-Parisi splitting functions used to describe single unresolved emission. However, when the unresolved particles are colour connected the factorisation is more complicated and we introduce new and general functions to describe the triple collinear and soft/collinear limits in addition to the known double soft gluon limits of Berends and Giele. As expected the triple collinear splitting functions obey an N=1 SUSY identity. To illustrate the use of these double unresolved approximations, we have examined the singular limits of the tree-level matrix elements for e+e- →5 partons when only three partons are resolved. When integrated over the unresolved regions of phase space, these expressions will be of use in evaluating the O(αs3) corrections to the three-jet rate in electron-positron annihilation. (orig.)
The NEXT double beta decay experiment
Laing, A.; NEXT Collaboration
2016-05-01
NEXT (Neutrino Experiment with a Xenon TPC) is a neutrinoless double-beta (ββ0v) decay experiment at Laboratorio Subterraneo de Canfranc (LSC). It is an electroluminescent Time Projection Chamber filled with high pressure 136Xe gas with separated function capabilities for calorimetry and tracking. Energy resolution and background suppression are the two key features of any neutrinoless double beta decay experiment. NEXT has both good energy resolution (handle for background identification provided by track reconstruction. We expect a background rate of 4 × 10-4 counts keV-1 kg-1 yr-1, and a sensitivity to the Majorana neutrino mass of between 80-160 meV (depending on NME) after a run of 3 effective years of the 100 kg scale NEXT-100 detector. The initial phase of NEXT-100, called NEW, is currently being commissioned at LSC. It will validate the NEXT background rate expectations and will make first measurements of the two neutrino ββ2v mode of 136Xe. Furthermore, the NEXT technique can be extrapolated to the tonne scale, thus allowing the full exploration of the inverted hierarchy of neutrino masses. These proceedings review NEXT R&D results, the status of detector commissioning at LSC and the NEXT physics case.
Neutrinoless double beta decay search with SNO+
Directory of Open Access Journals (Sweden)
Lozza V.
2014-01-01
Full Text Available The SNO+ experiment is the follow up of SNO. The detector is located 2 km underground in the Vale Canada Ltd.’s Creighton Mine near Sudbury, Ontario, Canada. The active volume of the detector consists of 780 tonnes of Linear Alkyl Benzene (LAB in an acrylic vessel of 12 m diameter, surrounded by about 9500 PMTs. The main goal of the SNO+ experiment is the search for neutrinoless double beta decay of 130Te. With an initial loading of 0.3% of natural tellurium (nearly 800 kg of 130Te, it is expected to reach a sensitivity on the effective Majorana neutrino mass of about 100 meV after several years of data taking. Designed as a general purpose neutrino experiment, other exciting physical goals can be explored, like the measurement of reactor neutrino oscillations and geo-neutrinos in a geologically-interesting location, watch of supernova neutrinos and studies of solar neutrinos. A first commissioning phase with water filled detector will start at the end of 2013, while the double beta decay phase will start in 2015.
A new double contrast barium enema
Energy Technology Data Exchange (ETDEWEB)
Park, Jun Sang; Cho, Won Sik; Lee, Sung Woo; Lee, Mun Gyu; Jeon, Jeong Dong; Jaun, Woo Ki; Han, Chung Yul [Inje College Paik Hospital, Pusan (Korea, Republic of)
1987-12-15
A new technic of the barium enema was proposed for the better colonic double contrast study with the average 204ml of 50w/v% barium, applied to 109 serial patients. The barium was introduced to sigmoid colon, and then pushed to a mid transverse colon by the air insufflation through an enema syringe, a new device. An advance to cecum is accomplished by the air insufflation and/or the position change of the patient. The barium transfer method was developed for the best spot film exposure, through colon, by the position change of the patient, the tilting of the x-ray table and the air insufflation with the enema syringe. The mean angle of the x-ray table tilted was -10 .deg. at the beginning the barium enema till the barium sent past the splenic flexure, -15 . deg. for the best lateral view of rectum and -18 .deg. for the bet prone PA view of rectosigmoid colon. This was a simple, better and economic double contrast barium enema for the cooperative patients.
Double Field Theory on Group Manifolds (Thesis)
Hassler, Falk
2015-01-01
This thesis deals with Double Field Theory (DFT), an effective field theory capturing the low energy dynamics of closed strings on a torus. It renders T-duality on a torus manifest by adding $D$ winding coordinates in addition to the $D$ space time coordinates. An essential consistency constraint of the theory, the strong constraint, only allows for field configurations which depend on half of the coordinates of the arising doubled space. I derive DFT${}_\\mathrm{WZW}$, a generalization of the current formalism. It captures the low energy dynamics of a closed bosonic string propagating on a compact group manifold. Its classical action and the corresponding gauge transformations arise from Closed String Field Theory up to cubic order in the massless fields. These results are rewritten in terms of a generalized metric and extended to all orders in the fields. There is an explicit distinction between background and fluctuations. For the gauge algebra to close, the latter have to fulfill a modified strong constrai...
Summability of Double Independent Random Variables
Directory of Open Access Journals (Sweden)
Ekrem Savaş
2008-09-01
Full Text Available We will examine double sequence to double sequence transformation of independent identically distribution random variables with respect to four-dimensional summability matrix methods. The main goal of this paper is the presentation of the following theorem. If maxÃ¢ÂÂ¡k,l|am,n,k,l|=maxÃ¢ÂÂ¡k,l|am,kan,l|=O(mÃ¢ÂˆÂ’ÃŽÂ³1O(nÃ¢ÂˆÂ’ÃŽÂ³2, ÃŽÂ³1,ÃŽÂ³2>0, then E|XÃ¢ÂŒÂ£|1+1/ÃŽÂ³1<Ã¢ÂˆÂž and E|XÃ¢ÂŒÂ£Ã¢ÂŒÂ£|1+1/ÃŽÂ³2<Ã¢ÂˆÂž imply that Ym,nÃ¢Â†Â’ÃŽÂ¼ almost sure P-convergence.
Double parton scattering in the ultraviolet: addressing the double counting problem
Diehl, Markus
2016-01-01
In proton-proton collisions there is a smooth transition between the regime of double parton scattering, initiated by two pairs of partons at a large relative distance, and the regime where a single parton splits into a parton pair in one or both protons. We present a scheme for computing both contributions in a consistent and practicable way.
Eddy turbulence, the double mesopause, and the double layer of atomic oxygen
Directory of Open Access Journals (Sweden)
M. N. Vlasov
2012-01-01
Full Text Available In this study, we consider the impact of eddy turbulence on temperature and atomic oxygen distribution when the peak of the temperature occurs in the upper mesosphere. A previous paper (Vlasov and Kelley, 2010 considered the simultaneous impact of eddy turbulence on temperature and atomic oxygen density and showed that eddy turbulence provides an effective mechanism to explain the cold summer and warm winter mesopause observed at high latitudes. Also, the prevalent role of eddy turbulence in this case removes the strong contradiction between seasonal variations of the O density distribution and the impact of upward/downward motion corresponding to adiabatic cooling/heating of oxygen atoms. Classically, there is a single minimum in the temperature profile marking the location of the mesopause. But often, a local maximum in the temperature is observed in the height range of 85–100 km, creating the appearance of a double mesopause (Bills and Gardner, 1993; Yu and She, 1995; Gusev et al., 2006. Our results show that the relative temperature maximum in the upper mesosphere (and thus the double mesopause can result from heating by eddy turbulence. According to our model, there is a close connection between the extra temperature peak in the mesosphere and the oxygen atom density distribution. The main feature of the O density height profile produced by eddy turbulence in our model is a double peak instead of a single peak of O density. A rocket experiment called TOMEX confirms these results (Hecht et al., 2004. Applying our model to the results of the TOMEX rocket campaign gives good agreement with both the temperature and oxygen profiles observed. Climatology of the midlatitude mesopause and green line emission shows that the double mesopause and the double layers of the green line emission, corresponding to the double O density height profile, are mainly observed in spring and fall (Yu and She, 1995; Liu and Shepherd, 2006. Further observations of
The International Double Taxation – causes and avoidance
Directory of Open Access Journals (Sweden)
Nicoleta Barbuta-Misu
2009-10-01
Full Text Available The politics and tax legislation being a manifestation of strict sovereignty of the State, the phenomenon of double taxation occursfrequently representing a difficult poison for the foreign trade activity, especially hindering investments abroad, technology transfer or proliferationoutside of the state of the companies’ branches. Therefore, international legal double taxation, by the repeated taxation of the income, it is anobstacle to the development of economic relations between states, reducing the revenue of the international operators and their interests in makinginvestment abroad. This paper presents the main causes that determine double taxation, its forms, i.e. the economic double taxation and theinternational legal double taxation, the need for eliminating the double taxation and avoidance methods.
Production of antihydrogen via double charge exchange
International Nuclear Information System (INIS)
Spectroscopy of the 1S-2S transition of antihydrogen confined in a neutral atom trap and comparison with the equivalent spectral line in hydrogen will provide an accurate test of CPT symmetry and the first one in a mixed baryon-lepton system. Also, with neutral antihydrogen atoms, the gravitational interaction between matter and antimatter can be tested unperturbed by the much stronger Coulomb forces. Antihydrogen is regularly produced at CERN's Antiproton Decelerator by three-body-recombination (TBR) of one antiproton and two positrons. The method requires injecting antiprotons into a cloud of positrons, which raises the average temperature of the antihydrogen atoms produced way above the typical 0.5 K trap depths of neutral atom traps. Therefore only very few antihydrogen atoms can be confined at a time. Precision measurements, like laser spectroscopy, will greatly benefit from larger numbers of simultaneously trapped antihydrogen atoms. Therefore, the ATRAP collaboration developed a different production method that has the potential to create much larger numbers of cold, trappable antihydrogen atoms. Positrons and antiprotons are stored and cooled in a Penning trap in close proximity. Laser excited cesium atoms collide with the positrons, forming Rydberg positronium, a bound state of an electron and a positron. The positronium atoms are no longer confined by the electric potentials of the Penning trap and some drift into the neighboring cloud of antiprotons where, in a second charge exchange collision, they form antihydrogen. The antiprotons remain at rest during the entire process, so much larger numbers of trappable antihydrogen atoms can be produced. Laser excitation is necessary to increase the efficiency of the process since the cross sections for charge-exchange collisions scale with the fourth power of the principal quantum number n. This method, named double charge-exchange, was demonstrated by ATRAP in 2004. Since then, ATRAP constructed a new combined
Measuring Visual Double Stars with Robotic Telescopes
Boyce, Pat; Boyce, Grady; Genet, Russell M.; Faisal Al-Zaben, Dewei Li, Yongyao Li, Aren Dennis, Zhixin Cao, Junyao Li, Steven Qu, Jeff Li, Michael Fene, Allen Priest, Stephen Priest, Rex Qiu, , and, Bill Riley
2016-06-01
produce four published research papers on seven visual double star systems and have our data added to the Washington Double Star Catalog. A school can adopt these techniques to do visual double star research with a minimal investment.
New exotics in the double beta decay contributions zoo
Klapdor-Kleingrothaus, H. V.; Päs, H.; Sarkar, U.
2000-01-01
We discuss the potential of neutrinoless double beta decay for testing Lorentz invariance and the weak equivalence principle as well as contributions from dilaton exchange gravity in the neutrino sector. While neutrino oscillation bounds constrain the region of large mixing of the weak and gravitational eigenstates, we obtain new constraints on violations of Lorentz invariance and the equivalence principle from neutrinoless double beta decay, applying even in the case of no mixing. Double bet...
Young's Double Slit Experiment in Quantum Field Theory
Kenmoku, Masakatsu; Kume, Kenji
2011-01-01
Young's double slit experiment is formulated in the framework of canonical quantum field theory in view of the modern quantum optics. We adopt quantum scalar fields instead of quantum electromagnetic fields ignoring the vector freedom in gauge theory. The double slit state is introduced in Fock space corresponding to experimental setup. As observables, expectation values of energy density and positive frequency part of current with respect to the double slit state are calculated which give th...
Forbidden induced subgraphs of double-split graphs
Alexeev, Boris; Fradkin, Alexandra; Kim, Ilhee
2010-01-01
In the course of proving the strong perfect graph theorem, Chudnovsky, Robertson, Seymour, and Thomas showed that every perfect graph either belongs to one of five basic classes or admits one of several decompositions. Four of the basic classes are closed under taking induced subgraphs (and have known forbidden subgraph characterizations), while the fifth one, consisting of double-split graphs, is not. A graph is doubled if it is an induced subgraph of a double-split graph. We find the forbid...
Image Resolution Enhancement Using Undecimated Double Density Wavelet Transform
Gopi, Varun P.; V. Suresh Babu; Dilna C.
2014-01-01
In this paper, an undecimated double density wavelet based image resolution enhancement technique is proposed. The critically sampled discrete wavelet transform (DWT) suffers from the drawbacks of being shift-variant and lacking the capacity to process directional information in images. The double density wavelet transform (DDWT) is an approximately shift-invariant transform capturing directional information. The undecimated double density wavelet transform (UDDWT) is an improvement of the DD...
Resumming double logarithms in the QCD evolution of color dipoles
E. Iancu; Madrigal, J. D.; Mueller, A. H.; Soyez, G.; Triantafyllopoulos, D.N.(European Centre for Theoretical Studies in Nuclear Physics and Related Areas (ECT*) and Fondazione Bruno Kessler, Strada delle Tabarelle 286, Villazzano (TN), I-38123, Italy)
2015-01-01
The higher-order perturbative corrections, beyond leading logarithmic accuracy, to the BFKL evolution in QCD at high energy are well known to suffer from a severe lack-of-convergence problem, due to radiative corrections enhanced by double collinear logarithms. Via an explicit calculation of Feynman graphs in light cone (time-ordered) perturbation theory, we show that the corrections enhanced by double logarithms (either energy-collinear, or double collinear) are associated with soft gluon em...
The double bind : Women, honour and sexuality in contemporary Ireland
Inglis, Tom; MacKeogh, Carol
2012-01-01
Irish women are caught in contradictory sexual discourses which create a cultural double bind. The legacy of Catholic Church teaching, in which the sexual honour of women revolves around their innocence and subservience, still lingers. This is gradually being replaced by media messages and images which portray women as sexually equal and independent. However, the media also portray sexually independent women as a threat to sexual moral order. The double bind reproduces double standards. The c...
Double layer formed by beam driven ion-acoustic turbulence
International Nuclear Information System (INIS)
Small amplitudes steady-state ion-acoustic double layers are observed to form in a plasma transversed by a beam of cold electrons. The importance of turbulence in maintaining the double layer is demonstrated. The measured wave spectrum is in approximate agreement with models deriveted from renornalized turbulence theory. The general features of the double layer are compared with results from particle simulation studies. (author)
An Unusual Appearance of Double Right Coronary Artery
Directory of Open Access Journals (Sweden)
Ahmet Akcay
2010-01-01
Full Text Available Double right coronary artery (RCA is an extremely rare coronary artery anomaly. We aimed to report an atherosclerotic double RCA which appeared after primary percutaneous intervention performed to treat acute inferior myocardial infarction. This is the first case in the literature, which the coronary arteries that can be accepted as double RCA have been hidden by total atherosclerotic occlusion of the proximal part of the RCA. In this paper, also the definition, correct diagnosis, and appropriate diagnostic methods for double RCA were discussed.
Canonical formulation and conserved charges of double field theory
Naseer, Usman
2015-01-01
We provide the canonical formulation of double field theory. It is shown that this dynamics is subject to primary and secondary constraints. The Poisson bracket algebra of secondary constraints is shown to close on-shell according to the C-bracket. A systematic way of writing boundary integrals in doubled geometry is given. By including appropriate boundary terms in the double field theory Hamiltonian, expressions for conserved energy and momentum of an asymptotically flat doubled space-time are obtained and applied to a number of solutions.
Researches on Parameters Calculation of Designing Double-tuned Filter
HE Yi-hong; Su, Heng
2013-01-01
Aiming at the question of parameter of double-tuned filter, A new method of designing double-tuned filter was proposed based on resonance frequency, by using the relationship that the impedance of double-tund filter and two parallel single tuned filters is equal and the resonance frequency of single tuned filter is the zero of the impedance of double-tuned filter. A simulation was established to prove the correctness of this method by using the software MATLAB in a power system. Simulation r...
On new phenomena of photon from modified double slit experiment
Liu, Haisheng
2010-01-01
A modified double slit experiment of light was implemented. In the experiment, a spatial shape filter is used to manipulate the shape of cross section of laser beam. When this modified laser beam was shined on the double slit, the intensity distribution of laser beam on double slit is asymmetrical. In this way, the laser light was directed to pass through only one or two slits of double slit in different sections. So the which-way information is predetermined before the photons pass through t...
Double-Shell Tank (DST) Utilities Specification
International Nuclear Information System (INIS)
This specification establishes the performance requirements and provides the references to the requisite codes and standards to he applied during the design of the Double-Shell Tank (DST) Utilities Subsystems that support the first phase of waste feed delivery (WFD). The DST Utilities Subsystems provide electrical power, raw/potable water, and service/instrument air to the equipment and structures used to transfer low-activity waste (LAW) and high-level waste (HLW) to designated DST staging tanks. The DST Utilities Subsystems also support the equipment and structures used to deliver blended LAW and HLW feed from these staging tanks to the River Protection Project (RPP) Privatization Contractor facility where the waste will be immobilized. This specification is intended to be the basis for new projects/installations. This specification is not intended to retroactively affect previously established project design criteria without specific direction by the program
Multiferroic Compounds with Double-Perovskite Structures
Directory of Open Access Journals (Sweden)
Noriya Ichikawa
2011-01-01
Full Text Available New multiferroic compounds with double-perovskite structures were synthesized. Bi2NiMnO6 was synthesized in bulk form by high-pressure synthesis and also in a thin-film form by epitaxial growth. The material showed both ferromagnetic and ferroelectric properties, i.e., the multiferroic property at low temperature. Bi2FeCrO6 was also fabricated in a (1 1 1 oriented BiFeO3/BiCrO3 artificial superlattice, with a 1/1 stacking period. The superlattice film showed ferromagnetic behavior and polarization switching at room temperature. In the compounds, Bi3+ ion, located at the A site in the perovskite structure, caused ferroelectric structural distortion, and the B-site ordering of the Ni2+ and Mn4+ ions (Fe3+ and Cr3+ ions in a rock-salt configuration led to ferromagnetism according to the Kanamori-Goodenough rule.
Numerical valuation of discrete double barrier options
Milev, Mariyan; Tagliani, Aldo
2010-03-01
In the present paper we explore the problem for pricing discrete barrier options utilizing the Black-Scholes model for the random movement of the asset price. We postulate the problem as a path integral calculation by choosing approach that is similar to the quadrature method. Thus, the problem is reduced to the estimation of a multi-dimensional integral whose dimension corresponds to the number of the monitoring dates. We propose a fast and accurate numerical algorithm for its valuation. Our results for pricing discretely monitored one and double barrier options are in agreement with those obtained by other numerical and analytical methods in Finance and literature. A desired level of accuracy is very fast achieved for values of the underlying asset close to the strike price or the barriers. The method has a simple computer implementation and it permits observing the entire life of the option.
Neutron interferometric double-resonance experiment
International Nuclear Information System (INIS)
In continuation of previous work explicitly demonstrating the basic quantum-mechanical principles of the static and the time-dependent superposition of spinors, a new double-resonance coil experiment is described, where a spin-flip process associated with an exchange of energy quanta happens in both beams of a perfect-crystal neutron interferometer. It is shown that under the given circumstances of neutron self-interference coherence is preserved in spite of the energy transfer to every neutron, which may stimulate renewed epistemological discussions about the interpretation of quantum mechanics. Furthermore quantum beating on a macroscopic time scale has been observed by introducing an exceedingly small energy difference of 8.6 x 10/sup -17/ eV between the two interfering beams. According to the statistical accuracy of the data thereby an energy sensitivity of 2.7 x 10/sup -19/ eV has been achieved
Neutrinoless Double Beta Decay: 2015 Review
Directory of Open Access Journals (Sweden)
Stefano Dell’Oro
2016-01-01
Full Text Available The discovery of neutrino masses through the observation of oscillations boosted the importance of neutrinoless double beta decay (0νββ. In this paper, we review the main features of this process, underlining its key role from both the experimental and theoretical point of view. In particular, we contextualize the 0νββ in the panorama of lepton number violating processes, also assessing some possible particle physics mechanisms mediating the process. Since the 0νββ existence is correlated with neutrino masses, we also review the state of the art of the theoretical understanding of neutrino masses. In the final part, the status of current 0νββ experiments is presented and the prospects for the future hunt for 0νββ are discussed. Also, experimental data coming from cosmological surveys are considered and their impact on 0νββ expectations is examined.
Standard Model as a Double Field Theory
Choi, Kang-Sin; Park, Jeong-Hyuck
2015-10-01
We show that, without any extra physical degree introduced, the standard model can be readily reformulated as a double field theory. Consequently, the standard model can couple to an arbitrary stringy gravitational background in an O (4 ,4 ) T -duality covariant manner and manifest two independent local Lorentz symmetries, Spin(1 ,3 )×Spin(3 ,1 ) . While the diagonal gauge fixing of the twofold spin groups leads to the conventional formulation on the flat Minkowskian background, the enhanced symmetry makes the standard model more rigid, and also stringy, than it appeared. The C P violating θ term may no longer be allowed by the symmetry, and hence the strong C P problem can be solved. There are now stronger constraints imposed on the possible higher order corrections. We speculate that the quarks and the leptons may belong to the two different spin classes.
Eccentricities of Double Neutron Star Binaries
Ihm, C M; Belczynski, K; Ihm, Catherine Mia; Kalogera, Vassiliki; Belczynski, Krzysztof
2005-01-01
Recent pulsar surveys have increased the number of observed double neutron stars (DNS) in our galaxy enough so that observable trends in their properties are starting to emerge. In particular, it has been noted that the majority of DNS have eccentricities less than 0.3, surprisingly low values for systems that must stay bound after two supernovae. To investigate this trend, we generate many different theoretical distributions of DNS eccentricities using Monte Carlo population synthesis methods. We determine which eccentricity distributions are most consistent with the observed sample of DNS binaries. In agreement with Chaurasia & Bailes (2005), we find that highly eccentric, close DNS are less likely to be observed because of their accelerated orbital evolution due to gravitational wave emission and possible early mergers. Based on our results for close DNS, we also find that models with vanishingly or moderately small kicks (sigma < about 50 km/s) are inconsistent with the current observed sample of s...
Multichannel applications of double relaxation oscillation Squids
International Nuclear Information System (INIS)
Double relaxation oscillation SQUIDs (DROSs) provided high flux-to-voltage transfers of larger than 1 mV Φ0-1 and simple flux-locked loop circuits were used for SQUID operation. We constructed two multichannel systems based on DROSs. The first system is a 40-channel planar gradiometer system consisting of integrated first-order pickup coils. average noise level of the 40 channels is 1 fT cm-1 Hz-1/2 at 100 Hz, corresponding to a field noise of 4 fT Hz-1/2, operating inside a magnetically shielded room. The second one is a 37-channel magnetometer system with 37 integrated magnetometers distributed on a spherical surface and measures field component normal to the head surface. The average noise of the magnetometers is 3 fT Hz-1/2 at 100 Hz. The two systems were applied to measure neuromagnetic fields. (author)
Double beta decay and neutrino mass models
Helo, J C; Ota, T; Santos, F A Pereira dos
2015-01-01
Neutrinoless double beta decay allows to constrain lepton number violating extensions of the standard model. If neutrinos are Majorana particles, the mass mechanism will always contribute to the decay rate, however, it is not a priori guaranteed to be the dominant contribution in all models. Here, we discuss whether the mass mechanism dominates or not from the theory point of view. We classify all possible (scalar-mediated) short-range contributions to the decay rate according to the loop level, at which the corresponding models will generate Majorana neutrino masses, and discuss the expected relative size of the different contributions to the decay rate in each class. We also work out the phenomenology of one concrete 2-loop model in which both, mass mechanism and short-range diagram, might lead to competitive contributions, in some detail.
WW Same-Sign Double Parton Scattering
Fascione, Eleanor
2016-01-01
Data collected by the CMS detector of 13 TeV centre of mass proton-proton collisions, provided during run 2 of the LHC, constitutes an integrated luminosity of $12.9\\,\\mathrm{fb}^{-1}$. This provides a tool to probe a previously unmeasured process, double parton scattering (DPS) in same-sign WW. Leptonic decay to a muon and associated neutrino was selected for each W boson. In this manner complicated backgrounds were all but negated. A BDT was trained against the most kinematically similar background, and appropriate statistical measures were used to estimate the contribution of fake leptons from W+jets and, to a lesser extent, ttbar. An expected uncertainty on the signal of 52\\% was extracted, or $2 \\sigma$ significance. An in-progress analysis will determine a limit on the production cross section.
Standard Model as a Double Field Theory.
Choi, Kang-Sin; Park, Jeong-Hyuck
2015-10-23
We show that, without any extra physical degree introduced, the standard model can be readily reformulated as a double field theory. Consequently, the standard model can couple to an arbitrary stringy gravitational background in an O(4,4) T-duality covariant manner and manifest two independent local Lorentz symmetries, Spin(1,3)×Spin(3,1). While the diagonal gauge fixing of the twofold spin groups leads to the conventional formulation on the flat Minkowskian background, the enhanced symmetry makes the standard model more rigid, and also stringy, than it appeared. The CP violating θ term may no longer be allowed by the symmetry, and hence the strong CP problem can be solved. There are now stronger constraints imposed on the possible higher order corrections. We speculate that the quarks and the leptons may belong to the two different spin classes. PMID:26551099
Homologous Pairing between Long DNA Double Helices
Mazur, Alexey K.
2016-04-01
Molecular recognition between two double stranded (ds) DNA with homologous sequences may not seem compatible with the B-DNA structure because the sequence information is hidden when it is used for joining the two strands. Nevertheless, it has to be invoked to account for various biological data. Using quantum chemistry, molecular mechanics, and hints from recent genetics experiments, I show here that direct recognition between homologous dsDNA is possible through the formation of short quadruplexes due to direct complementary hydrogen bonding of major-groove surfaces in parallel alignment. The constraints imposed by the predicted structures of the recognition units determine the mechanism of complexation between long dsDNA. This mechanism and concomitant predictions agree with the available experimental data and shed light upon the sequence effects and the possible involvement of topoisomerase II in the recognition.
Testing for double inflation with WMAP
International Nuclear Information System (INIS)
With the WMAP data we can now begin to test realistic models of inflation involving multiple scalar fields. These naturally lead to correlated adiabatic and isocurvature (entropy) perturbations with a running spectral index. We present the first full (9 parameter) likelihood analysis of double inflation with WMAP data and find that despite the extra freedom, supersymmetric hybrid potentials are strongly constrained with less than 7% correlated isocurvature component allowed when standard priors are imposed on the cosomological parameters. As a result we also find that Akaike and Bayesian model selection criteria rather strongly prefer single-field inflation, just as equivalent analysis prefers a cosmological constant over dynamical dark energy in the late universe. It appears that simplicity is the best guide to our universe
Doppel: more rival than double to prion.
Qin, K; O'Donnell, M; Zhao, R Y
2006-08-11
Conversion of normal cellular prion protein to the diseased form plays an essential role in transmissible spongiform encephalopathies such as mad cow disease and Creutzfeldt-Jakob disease. However, the normal physiological function of prion protein remains elusive. Doppel, a German synonym of double, was initially identified as a prion-like protein due to its structural and biochemical similarities. However, emerging evidence suggests that function of prion protein is more antagonistic to Doppel than synergistic. In this review, basic biochemical and structural similarities of prion protein and Doppel are introduced; evidence demonstrating antagonistic interaction of prion protein with Doppel is presented; and a potential novel activity of Doppel and prion protein in spermatogenesis, which could stimulate new avenues for research, is discussed. PMID:16781817
Chromosome doubling in vine cacti hybrids.
Tel-Zur, N; Abbo, S; Bar-Zvi, D; Mizrahi, Y
2003-01-01
We performed reciprocal crosses between the tetraploid Selenicereus megalanthus and the diploid Hylocereus species, H. undatus and H. polyrhizus. S. megalanthus x H. undatus gave rise to viable hexaploids and 6x-aneuploid hybrids rather than to the expected triploids. No genuine hybrids were obtained in the reciprocal cross. The pollen diameter of the tetraploid S. megalanthus varied widely, indicating the occurrence of unreduced gametes, while that of H. undatus pollen was very uniform, indicating an extremely low frequency of unreduced gametes. This finding suggests that the hexaploids were formed by chromosome doubling after the formation of the hybrid triploid zygote rather than by fusion of unreduced gametes of the two species. PMID:12920104
Double polarization experiments at intermediate energy
International Nuclear Information System (INIS)
At modern electron accelerators with highly polarized, intense, high duty factor beams double polarization coincidence experiments became feasible with good statistical accuracy. The strong potential towards the precise determination of small nucleon structure quantities is illustrated by two recent examples from MAMI. The measurement of GnE in the quasifree reaction D(e-vector, e'n-vector)p lead to a new parametrization of GnE which is significantly above the previously preferred one from elastic e-D scattering. A p(e-vector, e'p-vector)π0 experiment at the energy of the Δ resonance yields preliminary results for the longitudinal quadrupole mixing. Both experimental errors and model uncertainties are complementary to unpolarized measurements
GRINDING OF DOUBLE DISC GRINDING MACHINE
Institute of Scientific and Technical Information of China (English)
Hu Huiqing
2005-01-01
The grinding of two parallel sides of a component is accomplished with the accuracy and higher productivity by passing a blank through the truncated cone shape grinders, which are turned angles. The machine is designated by the name of double disc grinding machine (DDGM). Usually, it is used in the mass production. The relationship between these angles, the accuracy, productivity,allowance and parameters of the machine and technology is explained in detail by math, such as vector analysis, transformation of 3D space coordinates, etc. Therefore, in the aspects of qualitative and quantitative analyses, the grinding potential of DDGM is enormous increased and superior to conventional methods. Furthermore, the theoretical foundation of DDGM grinding design and technology is provided to improve, to expand and to create for future. The established machine design and practical experience of grinding technology will get great benefit by them.
RIBBED DOUBLE PIPE HEAT EXCHANGER: ANALYTICAL ANALYSIS
Directory of Open Access Journals (Sweden)
HUSSAIN H. AL-KAYIEM
2011-02-01
Full Text Available This paper presents the findings obtained by modeling a Double Pipe Heat Exchanger (DPHE equipped with repeated ribs from the inside for artificial roughing. An analytical procedure was developed to analyze the thermal and hydraulic performance of the DPHE with and without ribbing. The procedure was verified by comparing with experimental reported results and they are in good agreement. Several parameters were investigated in this study including the effect of ribs pitch to height ratios, P/e= 5, 10, 15, and 20, and ribs to hydraulic diameter ratios, e/Dh= 0.0595, 0.0765, and 0.107. These parameters were studied at various operating Reynolds number ranging from 2500 to 150000. Different installation configurations were investigated, too. An enhan-cement of 4 times in the heat transfer in terms of Stanton number was achieved at the expense of 38 times increase of pressure drop across the flow in terms of friction facto values.
Double-gated graphene-based devices
International Nuclear Information System (INIS)
We discuss transport through double-gated single- and few-layer graphene devices. This kind of device configuration has been used to investigate the modulation of the energy band structure through the application of an external perpendicular electric field, a unique property of few-layer graphene systems. Here we discuss technological details that are important for the fabrication of top-gated structures, based on electron-gun evaporation of SiO2. We perform a statistical study that demonstrates how-contrary to expectations-the breakdown field of electron-gun evaporated thin SiO2 films is comparable to that of thermally grown oxide layers. We find that a high breakdown field can be achieved in evaporated SiO2 only if the oxide deposition is directly followed by metallization of the top electrodes, without exposure of the SiO2 layer to air.
Extending Double Optical Gating to the Midinfrared
Gorman, Timothy; Camper, Antoine; Agostini, Pierre; Dimauro, Louis
2015-05-01
In the past decade there has been great interest in creating broadband isolated attosecond pulses (IAPs). Primarily these IAPs have been generated using Ti:Sapphire 800nm short pulses, namely through spatiotemporal gating with the attosecond lighthouse technique, amplitude gating, polarization gating, and double optical gating (DOG). Here we present theoretical calculations and experimental investigations into extending DOG to using a 2 μm driving wavelength, the benefits of which include extended harmonic cutoff and longer input driving pulse durations. It is proposed that broadband IAPs with cutoffs extending up to 250 eV can be generated in Argon by using >30 fs pulses from the passively-CEP stabilized 2 μm idler out of an optical parametric amplifier combined with a collinear DOG experimental setup.
Multichannel applications of double relaxation oscillation SQUIDs
Lee, Yong-Ho; Kwon, Hyukchan; Kim, Jin-Mok; Park, Yong-Ki
2001-12-01
Double relaxation oscillation SQUIDs (DROSs) provided high flux-to-voltage transfers of larger than 1 mV Φ0-1 and simple flux-locked loop circuits were used for SQUID operation. We constructed two multichannel systems based on DROSs. The first system is a 40-channel planar gradiometer system consisting of integrated first-order pickup coils. average noise level of the 40 channels is 1 fT cm-1 Hz-1/2 at 100 Hz, corresponding to a field noise of 4 fT Hz-1/2, operating inside a magnetically shielded room. The second one is a 37-channel magnetometer system with 37 integrated magnetometers distributed on a spherical surface and measures field component normal to the head surface. The average noise of the magnetometers is 3 fT Hz-1/2 at 100 Hz. The two systems were applied to measure neuromagnetic fields.
Double manganese(III) cesium triphosphate
International Nuclear Information System (INIS)
Double triphosphates have been identified in research on interactions in the P2O5-M2O3-Cs2O-H2O system, where M(III) = Al, Ga, Cr, Fe, at 570-770K, which have the M(III)Cs2 - P3O10 composition; here we report the identification of a new phase made under analogous conditions in a system containing Mn(III) together with some of its physicochemical properties. The product was analyzed for phosphorus by a colorimetric method, for manganese by titration with EDTA, and for cesium by atomic absorption. The x-ray phase analysis was performed with a DRON-3.0 diffractometer. The IR spectra were recorded. Thermogravimetry indicates that the product is MnCs2P3O10·H2O
Double blind placebo controlled exposure to molds
DEFF Research Database (Denmark)
Meyer, H W; Jensen, K A; Nielsen, K F;
2005-01-01
The objective was to develop an experimental setup for human exposure to mold spores, and to study the clinical effect of this exposure in sensitive subjects who had previously experienced potentially building-related symptoms (BRS) at work. From three water-damaged schools eight employees with a...... positive histamine release test to Penicillium chrysogenum were exposed double- blinded to either placebo, approximately 600,000 spores/m3 air of P. chrysogenum or approximately 350,000 spores/m3 of Trichoderma harzianum for 6 min on three separate days. A statistically significant rise in symptoms from...... mucous membranes appeared from the 9-graded symptom scale after exposure to T. harzianum or placebo. Dichotomizing the data, whether the participants experienced at least a two-step rise on the symptom scale or not, gave borderline increase in mucous membrane symptoms after exposure to P. chrysogenum. In...
Neutrinoless Double Beta Decay with SNO+
Hartnell, J
2012-01-01
SNO+ will search for neutrinoless double beta decay by loading 780 tonnes of linear alkylbenzene liquid scintillator with O(tonne) of neodymium. Using natural Nd at 0.1% loading will provide 43.7 kg of 150Nd given its 5.6% abundance and allow the experiment to reach a sensitivity to the effective neutrino mass of 100-200 meV at 90% C.L in a 3 year run. The SNO+ detector has ultra low backgrounds with 7000 tonnes of water shielding and self-shielding of the scintillator. Distillation and several other purification techniques will be used with the aim of achieving Borexino levels of backgrounds. The experiment is fully funded and data taking with light-water will commence in 2012 with scintillator data following in 2013.
Relativistic Spin Precession in the Double Pulsar
Breton, Rene P; Kramer, Michael; McLaughlin, Maura A; Lyutikov, Maxim; Ransom, Scott M; Stairs, Ingrid H; Ferdman, Robert D; Camilo, Fernando; Possenti, Andrea
2008-01-01
The double pulsar PSR J0737-3039A/B consists of two neutron stars in a highly relativistic orbit that displays a roughly 30-second eclipse when pulsar A passes behind pulsar B. Describing this eclipse of pulsar A as due to absorption occurring in the magnetosphere of pulsar B, we successfully use a simple geometric model to characterize the observed changing eclipse morphology and to measure the relativistic precession of pulsar B's spin axis around the total orbital angular momentum. This provides a test of general relativity and alternative theories of gravity in the strong-field regime. Our measured relativistic spin precession rate of 4.77 (+0.66,-0.65) degrees per year (68% confidence level) is consistent with that predicted by general relativity within an uncertainty of 13%.
Automorphisms of double coverings of curves
International Nuclear Information System (INIS)
We study automorphisms of curves that commute with each other. We prove that the order and the number of fixed points of one of them satisfy certain relations involving those of the other. Then, we specialize our results to the case of double coverings of curves. For instance, if the genus of the curve is at least 4γ + 2 and γ >= 1 (γ = the genus of the covered curve) we prove that the order of an automorphism is bounded above by 2γ + 1 (resp. 4γ + 2) provided it is prime (resp. it has at least five fixed points). We also improve Farkas' bound on the number of fixed points namely 4γ + 4 by showing that it involves the order of the automorphism except in the case of even order when such an improvement is obtained provided the automorphism and the γ-involution has at least one common fixed point. (author). 15 refs
Innovative Double Bypass Engine for Increased Performance
Manoharan, Sanjivan
Engines continue to grow in size to meet the current thrust requirements of the civil aerospace industry. Large engines pose significant transportation problems and require them to be split in order to be shipped. Thus, large amounts of time have been spent in researching methods to increase thrust capabilities while maintaining a reasonable engine size. Unfortunately, much of this research has been focused on increasing the performance and efficiencies of individual components while limited research has been done on innovative engine configurations. This thesis focuses on an innovative engine configuration, the High Double Bypass Engine, aimed at increasing fuel efficiency and thrust while maintaining a competitive fan diameter and engine length. The 1-D analysis was done in Excel and then compared to the results from Numerical Propulsion Simulation System (NPSS) software and were found to be within 4% error. Flow performance characteristics were also determined and validated against their criteria.
Railgun type double stage acceleration device
International Nuclear Information System (INIS)
Existent railgun type double stage acceleration devices for use in a thermonuclear device involved a problem so far that releasing amount of secondary electrons is reduced and destruction of electric insulation between rail electrodes is made unstable to increase a possibility of operation failure. In the present invention, there is disposed a means for accelerating plasmas to generate electric discharge between the rail electrodes by electric fields generated by a needle electrode disposed in the insulation material which supports the rail electrodes. Since ions of plasmas generated by laser beams are accelerated by high electric fields generated to the needle electrode, and collide against the rail electrodes at high energy, a large amount of secondary electrons are generated and the destruction of the electric insulation between a pair of rail electrodes is stabilized, to improve possibility of operation failure. (N.H.)
Design of double storage rings at MUSES
International Nuclear Information System (INIS)
Double storage rings (DSR) will play a role to perform various experiments of collision or merging of radio-isotope beams with ions, electron beams and X-rays produced from an undulator. The experiments will be performed at two crossing points. One is for collision of RI beam with electron with crossing angle 20 mrad. Another is for merging for ion beams with angle of 170 mrad. To perform these experiments with high luminosity, electron beam has two different operation modes. The emittance of 10-6 m*rad is prepared for the collision with RI and that of 10-8 m*rad is done for production of high brilliant X-ray. (author)
Weak decays and double beta decay
International Nuclear Information System (INIS)
Work to measure the Σ+ 0 degree differential cross section in the reaction K-p → Σ+π- at several incident K- momenta between 600 and 800 MeV/c as well as the asymmetries in the decays of polarized Σ+'s into protons and neutral pions and of polarized Σ-'s into neutrons and negative pions in collaboration with experimenters from Yale, Brookhaven, and the University of Pittsburgh (Brookhaven experiment 702) has been completed. Data from this experiment is currently being analyzed at Yale. Work is currently underway to develop and construct an experiment to search for neutrinoless double beta decay in thin foils of Mo100 in collaboration with experimenters from Lawrence Berkeley Laboratory. Development work on the solid state silicon detectors should be complete in the next six months and construction should e well underway within the next year
The double luminescence of Color Centers
International Nuclear Information System (INIS)
An experiment on the luminescence of Color Centers (CCs) carried out in 1987 at the ENEA Laboratories in Frascati had a negative result, but subsequent investigations showed that it was not a failure but rather a discovery of a new phenomenon. Since the coming of lasers, CCs in alkali halides have been successfully used as optically active materials, in particular FA Centers. One of these centers, well known for its medium infrared laser emission at 77 K, cooled further to 2 K emitted in the near infrared and without laser effect. Further investigations showed that the double luminescence was a fundamental property unknown until that time. This important discovery was achieved in Frascati because of the existence since 1973 of a solid and extensive expertise in the field of CCs, which continued over time and later on applied to the modern miniaturized photonic devices
Double-Copy Constructions and Unitarity Cuts
Bern, Zvi; Nohle, Josh
2016-01-01
The duality between color and kinematics enables the construction of multiloop gravity integrands directly from corresponding gauge-theory integrands. This has led to new nontrivial insights into the structure of gravity theories, including the discovery of enhanced ultraviolet cancellations. To continue to gain deeper understandings and probe these new properties, it is crucial to further improve techniques for constructing multiloop gravity integrands. In this paper, we show by example how one can alleviate difficulties encountered at the multiloop level by relaxing the color-kinematics duality conditions to hold manifestly only on unitarity cuts instead of globally on loop integrands. As an example, we use a minimal ansatz to construct an integrand for the two-loop four-point nonsupersymmetric pure Yang-Mills amplitude in $D$ dimensions that is compatible with these relaxed color-kinematics duality constraints. We then immediately obtain a corresponding gravity integrand through the double-copy procedure. ...
Analysis of Double-encapsulated Fuel Rods
Energy Technology Data Exchange (ETDEWEB)
Hales, Jason Dean [Idaho National Laboratory; Medvedev, Pavel G [Idaho National Laboratory; Novascone, Stephen Rhead [Idaho National Laboratory; Perez, Danielle Marie [Idaho National Laboratory; Williamson, Richard L [Idaho National Laboratory
2014-09-01
In an LWR fuel rod, the cladding encapsulates the fuel, contains fission products, and transfers heat directly to the water coolant. In some situations, it may be advantageous to separate the cladding from the coolant through use of a secondary cladding or capsule. This may be done to increase confidence that the fuel or fission products will not mix with the coolant, to provide a mechanism for controlling the rod temperature, or to place multiple experimental rodlets within a single housing. With an axisymmetric assumption, it is possible to derive closed-form expressions for the temperature profile in a fuel rod using radially-constant thermal conductivity in the fuel. This is true for both a traditional fuel-cladding rod and a double-encapsulated fuel (fuel, cladding, capsule) configuration. Likewise, it is possible to employ a fuel performance code to analyse both a traditional and a double-encapsulated fuel. In the case of the latter, two sets of gap heat transfer conditions must be imposed. In this work, we review the equations associated with radial heat transfer in a cylindrical system, present analytic and computational results for a postulated power and gas mixture history for IFA-744, and describe the analysis of the AFC-2A, 2B metallic fuel alloy experiments at the Advanced Test Reactor, including the effect of a release of fission products into the cladding-capsule gap. The computational results for these two cases were obtained using BISON, a fuel performance code under development at Idaho National Laboratory.
Optimal green tax reforms yielding double dividend
International Nuclear Information System (INIS)
In an stylized endogenous growth economy with a negative externality created by CO2 emissions and in which abatement activities are made by private firms, we find a wide range of dynamically feasible green tax reforms yielding the double dividend without any need to assume a complex production structure or tax system, or a variety of externalities in production. As a remarkable finding, we obtain certain scenarios in which increasing the emissions tax up to the Pigouvian level and removing completely the income tax is dynamically feasible and, also, it is the second-best reform. Hence, as a difference to previous literature, in these scenarios the first-best tax mix is implementable, allowing for the elimination of both environmental and non-environmental inefficiencies. Our result arises because of the consideration of public debt issuing and the management of the government budget balance with an intertemporal perspective. The result is obtained for an intermediate range of environmental bearing in preferences, the valid range being contingent on the pre-existing income tax rate. The type of tax reform that we propose could also be implemented for different energy taxes. - Highlights: → We use an endogenous growth model with a negative externality from CO2 emissions. → Abatement activities are made by private firms to reduce payment of emissions taxes. → We find dynamically feasible green tax reforms yielding the double dividend result. → Our result arises thanks to the inclusion of public debt issuing as a financing device. → The type of tax reform proposed can be implemented for other energy taxes.
Practical application of double-contingency protection
International Nuclear Information System (INIS)
The Westinghouse Commercial Fuel Fabrication Facility in Columbia, South Carolina, manufactures fuel assemblies and core components for the commercial nuclear power industry. The ammonium diurinate conversion process converts low-enriched (235U) uranium hexafluoride (UF6) or uranyl nitrate into ceramic-grade uranium dioxide (UO2) powder. The UO2 powder is then tumble blended in 1700-kg containers to ensure powder homogeneity and obtain necessary enrichments. The double-contingency principle is applied to all systems, processes, and components in which special nuclear material is processed, handled, or stored to ensure that an acceptable nuclear criticality margin of safety is maintained. The Nuclear Criticality Safety (NCS) Program at the Columbia plant is divided into three primary functions: analysis and evaluation, implementation, and compliance. The primary task in analysis and evaluation is to develop comprehensive criticality safety evaluations for all proposed new installations and system modifications. These evaluations involve identifying which of the nine physical process parameters directly affect neutron multiplication and establishing bounding assumptions and criticality safety limits (CSLs). The implementation function primarily consists of translating the open-quotes NCS-speakclose quotes (parameters, keff, contingencies, barriers, controls, etc.) into operator language (procedural requirements, valve positions, flow rates, pressures, temperatures, etc.) and communicating this information clearly to the manufacturing function through procedures and training. The compliance function deals primarily with conducting criticality safety inspections, audits, and process upset investigations. This paper presents two examples of the challenges associated with the practical implementation of the double-contingency principle to the chemical manufacturing process at the Columbia plant
Single-Arm Double-Mode Double-Order Planar Waveguide Interferometric Sensor
Sarkisov, Sergey S.
2000-01-01
We have met the goals stated in section one for the project. We have demonstrated the feasibility of a single-arm double-mode double-order waveguide interferometer as a cost efficient alternative to an optical chemical sensor. Experimental prototype was built as a dye-doped polymer waveguide with propagating modes of orders > and > of the same TM polarization. The prototype demonstrated sensitivity to ammonia of the order of 200 ppm per one full oscillation of the signal. Sensor based on polyimide doped with BCP can operate at elevated temperature up to 150 C. Upon the future funding, we are planning to optimize the light source, material and the design in order to achieve sensitivity of the order of 1 ppm per full oscillations.
Regular motions in double bars. I. Double-frequency orbits and loops
Maciejewski, Witold; Athanassoula, E.
2007-01-01
Bars in galaxies are mainly supported by particles trapped around stable periodic orbits. These orbits represent oscillatory motion with only one frequency, which is the bar driving frequency, and miss free oscillations. We show that a similar situation takes place in double bars: particles get trapped around parent orbits, which in this case represent oscillatory motion with two frequencies of driving by the two bars, and which also lack free oscillations. Thus the parent orbits, which const...
Double-positron decay, positron-emitting K capture, and double K capture
International Nuclear Information System (INIS)
We have calculated the lifetimes of the two-neutrino and neutrinoless double-positron decay, K-capture, and KK-capture processes for several nuclei. It is found that the two-neutrino KK-capture process is a dominant channel with a lifetime of 1023--1024 yr, whereas the neutrinoless processes have lifetimes greater than 1027yr if the currently accepted upper limits on the lepton-number-violation parameters are used
Radiation resistance of double-type double-sided 3D pixel sensors
Fernandez, M; Lozano, M; Munoz, F.J; Pellegrini, G; Quirion, D; Rohe, T; Vila, I
2013-01-01
The proposed high-luminosity upgrade of the Large Hadron Collider is expected to increase the instantaneous luminosity at the experiments' interaction points by a factor of ten. The vertex detector will be the subsystem most affected by the luminosity increase, raising substantially their occupancy and radiation-induced damage. To preserve the vertex physics performance under these new conditions, current pixel technologies have to be improved. Hybrid pixel sensors with double-sided double-type vertical electrodes (3D sensors) are becoming a mature technology for the detector layers closest to the interaction point due to their intrinsic radiation hardness. In addition, the double-sided implementation of the 3D pixel technology provides some additional technical advantages with respect to the single-sided implementation. For this study, 3D pixel sensors manufactured at the Centro Nacional de Microelectrónica of Barcelona (IMB-CNM) have been bonded to the PSI46 readout chip currently used by the Compact Muon ...
New single- and double-parton scattering mechanisms for double charmed meson production
Szczurek, Antoni; Saleev, Vladimir A; Shipilova, Alexandra V
2016-01-01
We discuss charm meson-meson pair production recently observed by the LHCb Collaboration at $\\sqrt{s}$ = 7 TeV in proton-proton scattering. We examine double-parton scattering (DPS) mechanisms of double $c \\bar c$ production and following $cc \\to D^{0}D^{0}$ hadronization as well as double $g$ and mixed $g c\\bar c $ production with $gg \\to D^{0}D^{0}$ and $gc \\to D^{0}D^{0}$ hadronization calculated with the help of the scale-dependent KKKS08 fragmentation functions. A new single-parton scattering (SPS) mechanism of $gg$ production is also taken into consideration. Calculated differential distributions as a function of transverse momentum $p_{T}$ of one of the $D^{0}$ mesons, pair invariant mass $M_{D^{0}D^{0}}$ and azimuthal angle $\\varphi_{D^{0}D^{0}}$ distributions are confronted with the measured ones. The manifestation of the new SPS mechanisms with $g \\to D^{0}$ fragmentation within the scale-dependent fragmentation scheme change the overall picture suitable for standard scale-independent fragmentation ...
49 CFR 236.723 - Circuit, double wire; line.
2010-10-01
... 49 Transportation 4 2010-10-01 2010-10-01 false Circuit, double wire; line. 236.723 Section 236.723 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD... § 236.723 Circuit, double wire; line. An electric circuit not employing a common return wire; a...
The Double-Entry Journal in Literature Classes.
Nugent, Harold; Nugent, Susan
The double-entry journal requires students to write affective response statements to literature readings and to compare such entries with those of classmates. Use of the double-entry journal is intended to activate students' prior learning and present feelings, foster collaborative learning, integrate major language skills, and encourage the…
Double-Wavelet Neuron Based on Analytical Activation Functions
Bodyanskiy, Yevgeniy; Lamonova, Nataliya; Vynokurova, Olena
2007-01-01
In this paper a new double-wavelet neuron architecture obtained by modification of standard wavelet neuron, and its learning algorithm are proposed. The offered architecture allows to improve the approximation properties of wavelet neuron. Double-wavelet neuron and its learning algorithm are examined for forecasting non-stationary chaotic time series.
A double-sum Kronecker-type identity
Mortenson, Eric T.
2016-01-01
We prove a double-sum analog of an identity known to Kronecker and then express it in terms of functions studied by Appell and Kronecker's student Lerch, in so doing we show that the double-sum analog is of mixed mock modular form.
Degeneracy of resonances in a double barrier potential
Energy Technology Data Exchange (ETDEWEB)
Hernandez, E.; Mondragon, A. [Instituto de Fisica, UNAM, Mexico DF (Mexico); Jauregui, A. [Departamento de Fisica, Universidad de Sonora, Hermosillo, Sonora (Mexico)
2000-06-23
Degeneracy of resonant states and double poles in the scattering matrix of a double barrier potential are contrived by adjusting the parameters of the system. The cross section, scattering wavefunction and Gamow eigenfunction are computed at degeneracy. Some general properties of the degeneracy of resonances are exhibited and discussed in this simple quantum system. (author)
The Quantum Double in Integrable Quantum Field Theory
Bernard, D.; Leclair, A.
1992-01-01
Various aspects of recent works on affine quantum group symmetry of integrable 2d quantum field theory are reviewed and further clarified. A geometrical meaning is given to the quantum double, and other properties of quantum groups. Multiplicative presentations of the Yangian double are analyzed.
False Position, Double False Position and Cramer's Rule
Boman, Eugene
2009-01-01
We state and prove the methods of False Position (Regula Falsa) and Double False Position (Regula Duorum Falsorum). The history of both is traced from ancient Egypt and China through the work of Fibonacci, ending with a connection between Double False Position and Cramer's Rule.
Nonlocal Double-Slit Interference with Pseudothermal Light
Gao, Lu; Xiong, Jun; Lin, Lu-Fang; Wang, Wei; Zhang, Su-Heng; Wang, Kaige
2007-01-01
We perform a nonlocal double-slit interference experiment with pseudothermal light. The experimental result exhibits a typical double-slit interference fringe in the intensity correlation measurement, in agreement with the theoretical analysis by means of the property of the second-order spatial correlation of field.
Progress of Double Star Program 2006-2008
Institute of Scientific and Technical Information of China (English)
LIU Zhenxing; CAO Jinbin
2008-01-01
This paper presents the status of two satellites of Double Star Program, and a part of scientific results based on the data of Double Star Program obtained during the period of 2006-2008.Other scientific results in the magnetospheric physics research can be found in "Multi scale physical process in the magnetosphere" of this issue.
Application of the double-contingency principle within BNFL
International Nuclear Information System (INIS)
Historically, the double-contingency principle has been used for criticality assessment within British Nuclear Fuels plc (BNFL). This paper outlines what is understood by the double-contingency principle to illustrate how it is applied in criticality safety assessments and to highlight various problem areas that are encountered and, where possible, how they might be solved
The double-contingency principle: An historical perspective
International Nuclear Information System (INIS)
Standard ANSI/ANS-8.1 states the double contingency principle as: Process designs should, in general, incorporate sufficient factors of safety to require at least two unlikely, independent, and concurrent changes in process conditions before a criticality accident is possible. This paper presents a perspective on the double contingency principle
Method for double-sided processing of thin film transistors
Yuan, Hao-Chih; Wang, Guogong; Eriksson, Mark A.; Evans, Paul G.; Lagally, Max G.; Ma, Zhenqiang
2008-04-08
This invention provides methods for fabricating thin film electronic devices with both front- and backside processing capabilities. Using these methods, high temperature processing steps may be carried out during both frontside and backside processing. The methods are well-suited for fabricating back-gate and double-gate field effect transistors, double-sided bipolar transistors and 3D integrated circuits.
Photometry of Faint and Wide Doubles in Sagitta
Knapp, Wilfried; Thuemen, Chris
2016-02-01
Images of several double stars in Sagitta published on the "Double Star Imaging Project" Yahoo Group page suggest magnitude issues compared with the corresponding WDS catalog data per April 2015. Taking additional images with V-filter enabled photometry for these pairs, provided confirming results.
Photometry of Faint and Wide Doubles in Vulpecula
Knapp, Wilfried; Thuemen, Chris
2016-04-01
Images of several double stars in Vulpecula published on the "Double Star Imaging Project" Yahoo Group page suggest magnitude issues compared with the corresponding WDS catalog data per April 2015. Taking additional images with V-filter enabled photometry for these pairs, providing confirming results.
Double Consonants in English: Graphemic, Morphological, Prosodic and Etymological Determinants
Berg, Kristian
2016-01-01
What determines consonant doubling in English? This question is pursued by using a large lexical database to establish systematic correlations between spelling, phonology and morphology. The main insights are: Consonant doubling is most regular at morpheme boundaries. It can be described in graphemic terms alone, i.e. without reference to…
Thin and fat sets for doubling measures in metric spaces
Ojala, Tuomo; Suomala, Ville
2011-01-01
We consider sets in uniformly perfect metric spaces which are null for every doubling measure of the space or which have positive measure for all doubling measures. These sets are called thin and fat, respectively. In our main results, we give sufficient conditions for certain cut-out sets being thin or fat.
Geothermal and hydrocarbon esploration - The double play synergy
Wees, J.D. van; Kramers, L.; Mijnlieff, H.F.; Jong, S. de; Scheffers, B.
2014-01-01
There is a clear synergy possible in geothermal and hydrocarbon exploration if wells are targeted in a double play concept. In the Netherlands, clastic aquifers which have been explored extensively by the hydrocarbon industry and are now targeted for geothermal energy qualify well for a double play.
Project Half Double, Preliminary Results for Phase 1, June 2016
DEFF Research Database (Denmark)
Svejvig, Per; Ehlers, Michael; Thorp Adland, Karoline;
2016-01-01
activities carried out within the framework of the projects. The formal part of Project Half Double was initiated in June 2015. We started out by developing, refining and testing the Half Double methodology on seven pilot projects in the first phase of the project, which will end June 2016. The current...
Double congenital patella: case report and review of the literature
International Nuclear Information System (INIS)
The authors report a case of double congenital patella, which is a rare finding. This anomaly was studied using radiography, CT and MR. Magnetic resonance imaging has enabled us to make an accurate anatomical evaluation of the double congenital patella. (orig.). With 5 figs., 2 tabs
Double congenital patella: case report and review of the literature
Energy Technology Data Exchange (ETDEWEB)
Visconti, D. [Servizio di Radiologia Ospedale Cavalese Trento, Via Dossi 17, I-38 033 Cavalese (Italy); Della Sala, S.W. [U. O. di Radiologia, Sezione TAC RM, Ospedale S. Chiara, I-38100 Trento (Italy); Bianchini, G. [A. O. di Ortopedia e Traumatologia, Ospedale Cles, I-38023 Trento (Italy); Manera, V. [U. O. di Radiologia, Sezione TAC RM, Ospedale S. Chiara, I-38100 Trento (Italy)
1996-08-01
The authors report a case of double congenital patella, which is a rare finding. This anomaly was studied using radiography, CT and MR. Magnetic resonance imaging has enabled us to make an accurate anatomical evaluation of the double congenital patella. (orig.). With 5 figs., 2 tabs.
Resummation of double logarithms in electroweak high energy processes
Fadin, V S; Martin, A D; Melles, M
2000-01-01
At future linear $e^+e^-$ collider experiments in the TeV range, Sudakov double logarithms originating from massive boson exchange can lead to significant corrections to the cross sections of the observable processes. These effects are important for the high precision objectives of the Next Linear Collider. We use the infrared evolution equation, based on a gauge invariant dispersive method, to obtain double logarithmic asymptotics of scattering amplitudes and discuss how it can be applied, in the case of broken gauge symmetry, to the Standard Model of electroweak processes. We discuss the double logarithmic effects to both non-radiative processes and to processes accompanied by soft gauge boson emission. In all cases the Sudakov double logarithms are found to exponentiate. We also discuss double logarithmic effects of a non-Sudakov type which appear in Regge-like processes.
An exactly soluble model of a shallow double well
Energy Technology Data Exchange (ETDEWEB)
Muñoz-Vega, R., E-mail: rodrigo.munoz@uacm.edu.mx [Universidad Autónoma de la Ciudad de México, Centro Histórico, Fray Servando Teresa de Mier 92, Col. Centro, Del. Cuauhtémoc, México DF, CP 06080 (Mexico); López-Chávez, E., E-mail: elopezc@hotmail.com [Universidad Autónoma de la Ciudad de México, Centro Histórico, Fray Servando Teresa de Mier 92, Col. Centro, Del. Cuauhtémoc, México DF, CP 06080 (Mexico); Salinas-Hernández, E., E-mail: esalinas@ipn.mx [ESCOM-IPN, Av Juan de Dios Bátiz s/n, Unidad Profesional Adolfo López Mateos, Col Lindavista, Del G A Madero, México DF, CP 07738 (Mexico); Flores-Godoy, J.-J., E-mail: job.flores@ibero.mx [Departamento de Física y Matemáticas, Universidad Iberoamericana, Prol. Paseo de la Reforma 880, Col Lomas de Santa Fe, Del A Obregón, México DF, CP 01219 (Mexico); Fernández-Anaya, G., E-mail: guillermo.fernandez@ibero.com [Departamento de Física y Matemáticas, Universidad Iberoamericana, Prol. Paseo de la Reforma 880, Col Lomas de Santa Fe, Del A Obregón, México DF, CP 01219 (Mexico)
2014-06-13
Shallow one-dimensional double-well potentials appear in atomic and molecular physics and other fields. Unlike the “deep” wells of macroscopic quantum coherent systems, shallow double wells need not present low-lying two-level systems. We argue that this feature, the absence of a low-lying two-level system in certain shallow double wells, may allow the finding of new test grounds for quantum mechanics in mesoscopic systems. We illustrate the above ideas with a family of shallow double wells obtained from reflectionless potentials through the Darboux–Bäcklund transform. - Highlights: • We present double wells not conforming to the low-lying two-state system model. • Models similar to ours appear in atomic and molecular physics. • Here there is no classically prohibited region between wells. • The ground probability is peaked at the position of classical unstable equilibrium in this models.
Mechanically tough, elastic and stable rope-like double nanohelices
Dai, L.; Huang, X. J.; Dong, L. X.; Zhang, Q.; Zhang, L.
2014-07-01
Double helix nanostructures have been the object of intense theoretical and experimental investigations in recent years due to their various types of available materials and unique morphology. Among these structures, rope-like double nanohelices of two strands in contact along a line can be obtained using any one-dimensional nanostructure. In this work, we establish a novel theory for quantitatively exploring the statics and dynamics of rope-like double nanohelices by employing the concept of the extensible Cosserat curve. The rope-like double nanohelices are tough, relatively elastic, and mechanically stable, which agrees well with the experiments. The characteristics of the interaction between the two strands, the tensile modulus and the torque are precisely described and explained across the entire stretching region. The proposed model offers in depth quantitative insight into the mechanics of double helix nanostructures, and supplies a reliable reference for further experimental research.
The double copy: Bremsstrahlung and accelerating black holes
Luna, Andres; Nicholson, Isobel; O'Connell, Donal; White, Chris D
2016-01-01
Advances in our understanding of perturbation theory suggest the existence of a correspondence between classical general relativity and Yang-Mills theory. A concrete example of this correspondence, which is known as the double copy, was recently introduced for the case of stationary Kerr-Schild spacetimes. Building on this foundation, we examine the simple time-dependent case of an accelerating, radiating point source. The gravitational solution, which generalises the Schwarzschild solution, includes a non-trivial stress-energy tensor. This stress-energy tensor corresponds to a gauge theoretic current in the double copy. We interpret both of these sources as representing the radiative part of the field. Furthermore, in the simple example of Bremsstrahlung, we determine a scattering amplitude describing the radiation, maintaining the double copy throughout. Our results provide the strongest evidence yet that the classical double copy is directly related to the BCJ double copy for scattering amplitudes.
Torus-doubling process via strange nonchaotic attractors
International Nuclear Information System (INIS)
Torus-doubling bifurcations typically occur only a finite number of times. It has been assumed that torus-doubling bifurcations in quasiperiodically forced systems are interrupted by the appearance of strange nonchaotic attractors (SNAs). In the present Letter, we study a quasiperiodically forced noninvertible map and report the occurrence of a torus-doubling process via SNAs. The mechanism of this process is numerically clarified. Furthermore, this process is experimentally demonstrated in a switched-capacitor integrated circuit. -- Highlights: ► We report the occurrence of a torus-doubling process via strange nonchaotic attractors (SNAs). ► The process consists of the gradual fractalization of a torus and the Heagy–Hammel transition. ► The torus-doubling process via SNAs is also experimentally demonstrated in an electronic circuit.
An exactly soluble model of a shallow double well
International Nuclear Information System (INIS)
Shallow one-dimensional double-well potentials appear in atomic and molecular physics and other fields. Unlike the “deep” wells of macroscopic quantum coherent systems, shallow double wells need not present low-lying two-level systems. We argue that this feature, the absence of a low-lying two-level system in certain shallow double wells, may allow the finding of new test grounds for quantum mechanics in mesoscopic systems. We illustrate the above ideas with a family of shallow double wells obtained from reflectionless potentials through the Darboux–Bäcklund transform. - Highlights: • We present double wells not conforming to the low-lying two-state system model. • Models similar to ours appear in atomic and molecular physics. • Here there is no classically prohibited region between wells. • The ground probability is peaked at the position of classical unstable equilibrium in this models
Phase singularity in the diffracted field from Fresnel's double mirror
Aalipour, Rasoul; Taghi Tavassoly, M.
2013-05-01
It is shown that when a coherent beam of light illuminates a Fresnel's double mirror, Fresnel diffraction becomes appreciable. The subject fundamentally differs from interference. We calculate the diffracted field by applying Fresnel-Kirchhoff integral. We modified the common Fresnel's double mirror by imposing an initial height between the mirrors, as the height is chosen small enough so that the application of Fresnel's double mirror is maintained. We show by simulation and experiment that a phase singularity causes from the initial height and modifies the diffracted field from the Fresnel's double mirror. One can adjust the location of the line singularity by changing the angle between the mirrors. Also, the anomalous behavior of a polychromatic beam diffracted from the modified Fresnel's double mirror at the neighborhood of the line singularity, is investigated by simulation.
Double-diffusive inner core convective translation
Deguen, Renaud; Alboussière, Thierry; Labrosse, Stéphane
2016-04-01
The hemispherical asymmetry of the inner core has been interpreted as resulting form a high-viscosity mode of inner core convection, consisting in a translation of the inner core. With melting on one hemisphere and crystallization on the other one, inner core translation would impose a strongly asymmetric buoyancy flux at the bottom of the outer core, with likely strong implications for the dynamics of the outer core and the geodynamo. The main requirement for convective instability in the inner core is an adverse radial density gradient. While older estimates of the inner core thermal conductivity favored a superadiabatic temperature gradient and the existence of thermal convection, the much higher values recently proposed makes thermal convection very unlikely. Compositional convection might be a viable alternative to thermal convection: an unstable compositional gradient may arise in the inner core either because the light elements present in the core are predicted to become increasingly incompatible as the inner core grows (Gubbins et al. 2013), or because of a possibly positive feedback of the development of the F-layer on inner core convection. Though the magnitude of the destabilizing effect of the compositional field is predicted to be similar to or smaller than the stabilizing effect of the thermal field, the huge difference between thermal and chemical diffusivities implies that double-diffusive instabilities can still arise even if the net density decreases upward. We propose here a theoretical and numerical study of double diffusive convection in the inner core that demonstrate that a translation mode can indeed exist if the compositional field is destabilizing, even if the temperature profile is subadiabatic, and irrespectively of the relative magnitude of the destabilizing compositional gradient and stabilizing temperature field. The predicted inner core translation rate is similar to the mean inner core growth rate, which is more consistent with
Output speed and flow of double-acting double-stator multi-pumps and multi-motors
Institute of Scientific and Technical Information of China (English)
De-sheng WEN; Zhi-li WANG; Jun GAO; Yong ZHANG; Shi-jun LV; Tetsuhiro TSUKIJI
2011-01-01
The primary focus of this study was to investigate a series of novel motors and pumps, based on a new type of structure called double-stator. The double-stator structure can be used as pump or motor just based on the application requirements. A certain amount of pumps or motors can be formed in one shell, and these sub-pumps or sub-motors can work alone or be combined without influence on each other. So this kind of double-stator pump (motor) is called a multi-pump (multi-motor). Through the analysis of multifarious connection modes of the double-acting double-stator multi-pumps and multi-motors, the mathematical expressions of the output flow rate and the rotational speed are acquired. The results indicate that a quantity of different flow rates can be provided by one fixed-displacement multi-pump under the condition of unalterable driven speed by electromotor. Likewise,when supplied by settled input flow, without complex variable mechanism, the functions of double-speed, multiple-speed, and even differential connection can be obtained by employing the use of a double-stator multi-motor. The novel hydraulic transmission is made of such a double-stator multi-pump and multi-motor, and has broad application prospects.
Effects of radiation on DNA's double helix
2003-01-01
The blueprint of life, DNA's double helix is found in the cells of everything from bacteria to astronauts. Exposure to radiation(depicted at right) such as X-rays (upper) or heavy ion particles (lower), can damage DNA and cause dire consequences both to the organism itself and to future generations. One of NASA's main goals is to develop better radiation shielding materials to protect astronauts from destructive radiation in space. This is particularly important for long space missions. NASA has selected researchers to study materials that provide better shielding. This research is managed by NASA's Office of Biological and Physical Research and is supported by the Microgravity Science and Applications Department at NASA's Marshall Center. During International Space Station Expedition Six, the Extravehicular Activity Radiation Monitoring (EVARM) will continue to measure radiation dosage encountered by the eyes, internal organs and skin during specific spacewalks, and relate it to the type of activity, location and other factors. An analysis of this information may be useful in mitigating potential exposure to space walkers in the future. (Illustration by Dr. Frank Cucinotta, NASA/Johnson Space Center, and Prem Saganti, Lockheed Martin)