70,007 research outputs found
A value for bi-cooperative games
No full textBi-cooperative games were introduced by Bilbao et al. as a generalization of TU cooperative games, in which each player can participate positively, negatively, or not at all. In this paper, we propose a definition of a share of the worth obtained by some players after they decided on their participation in the game. It turns out that the cost allocation rule does not look for a given player to her contribution at the opposite participation option to the one she chooses. The relevance of the value is discussed on several examples.Bi-cooperative games ;Value ;Efficiency
The development of high field magnets utilizing Bi-2212 wind & react insert coils
No full textWind & react Bi-2212 inserts have been manufactured and tested inside a wide-bore NbTi-Nb3Sn magnet providing a background field up to 20T at 4.2K. A pair of six-layer concentric coils both achieved critical currents of 350 A (JE = 200 A/mm2) in a 20T background field. A thicker 14-layer insert made from 119m of round wire had a critical quench current IQ of 287A (JE = 162 A/mm2) at the same field and contributed to a combined central field of 22.5 T. This is a record for a fully superconducting magnet at 4.2 K. The 14-layer coil, equipped with an external protective shunt, was used for an extensive series of quench measurements and endured >150 quenches without damage. Minimum quench energies were found to be in the range of 200-500mJ in background fields of 15-20T when the coil carried 70-95% of its critical quench current
On the bi-dimensionality of liquidity.
No full textVariations in overall liquidity can be measured by simultaneous changes in both immediacy costs and depth. Liquidity changes, however, are ambiguous whenever both liquidity dimensions do not reinforce each other. In this paper, ambiguity is characterized using an instantaneous time-varying elasticity concept. Several bi-dimensional liquidity measures that cope with the ambiguity problem are constructed. First, it is shown that bi-dimensional measures are superior since commonalities in overall liquidity cannot be fully explained by the common factors in one-dimensional proxies of liquidity. Second, it is shown that an infinitesimal variation in either market volatility or trading activity augments the probability of observing an unambiguous liquidity adjustment. Ambiguity strongly depends on the expected (deterministic) component of volatility.liquidity; measurement; immediacy; depth; elasticity; ambiguity; bi-dimensional;
VEGF 936C > T Polymorphism and Association of BI-RADS Score in Women with Suspected Breast Cancer
No full textPurpose: Vascular endothelial growth factor (VEGF) is a potent regulator of angiogenesis and thereby involved in the development and progression of solid tumors. A 936C> T polymorphism in the VEGF gene has been associated with reduced VEGF plasma levels. Purpose of the present study was to analyze the potential association between VEGF genotype and radiological appearance of breast lesions by mammography. Materials and Methods: Fifty two women with 54 suspected breast lesions were analyzed by the use of mammography with the standard breast imaging reporting and data systems (BI-RADS). Germline VEGF genotype was determined in all subjects by allele-specific digestion of amplification products. An open biopsy was performed on all lesions. Results: VEGF CC, CT and TT genotypes were found in 41 (79%), 9 (17%) and 2 (4%) patients. By mammography 26, 16 and 12 suspected breast lesions were classified as BI-RADS scores 3, 4 and 5, respectively. Both carriers of the TT genotype were classified as BI-RADS 5, whereas among CT or CC carriers, BI-RADS scores 3, 4 and 5 were found in 26, 16 and 10 subjects (P T polymorphism seems to be associated with a high BI-RADS score in women with suspicious breast lesions
Photochemical ligand ejection from non-sterically promoted Ru(ii)bis(diimine) 4,4′-bi-1,2,3-triazolyl complexes
No full textComplexes of the form [Ru(diimine)2(btz)]2+ (btz = 1,1′-dibenzyl-4,4′-bi-1,2,3-triazolyl) are observed to undergo photochemical ejection of the btz ligand in the absence of any promotion through steric congestion to generate cis-bis(solvent) complexes [Ru(diimine)2(solvent)2]2+.
Graphical abstract: Photochemical ligand ejection from non-sterically promoted Ru(ii)bis(diimine) 4,4′-bi-1,2,3-triazolyl complexe
Settling of finite-size particles in isotropically forced, homogeneous turbulence: interface-resolved simulations
No full textWe have simulated the gravity-induced settling of finite-size particles in a turbulent background flow which is forced in a statistically-stationary fashion. The simulations are accurately resolving the solid-fluid interface with the aid of an immersed boundary technique [1]. The parameters of the simulation are (apart from background turbulence) identical to those of reference [2], where particle clustering was observed at a Galileo number of 178 and a solid volume fraction of 0.005. In the present case, it is found that a relative turbulence intensity of 0.24 leads to the disappearance of the clusters; as a consequence, the increase in average particle settling velocity found in [2] also vanishes. [1] M. Uhlmann. An immersed boundary method with direct forcing for the simulation of particulate flows. J. Comput. Phys., 209(2):448–476, 2005. [2] M. Uhlmann and T. Doychev. Sedimentation of a dilute suspension of rigid spheres at intermediate Galileo numbers: the effect of clustering upon the particle motion. J. Fluid Mech., 752:310–348, 2014
Creep of Cu-Bi Alloys with High Bi Content Near and Above Melting Temperature of Bi
No full textCu-Bi alloy with high Bi content can be used for thermal surge protection and energy storage. For these applications, creep at high temperatures, including temperatures above the melting temperature of Bi, T-m,T-Bi, becomes important. Accordingly, the creep behavior of Cu-Bi alloys, comprising 30 and 40 vol pct Bi, was studied under compression at temperatures above and below T-m,T-Bi. At 200 degrees C, which is below T-m,T-Bi, Cu-Bi showed a stress exponent of similar to 4 at high stresses and similar to 1 at low stresses. Finite element analysis revealed that the creep behavior of Cu-Bi at 200 degrees C was predominantly governed by Bi. On the other hand, at temperatures higher than T-m,T-Bi, Cu-Bi showed a short transient stage at high stresses, followed by sudden failure of the material. However, at low stresses, the sample first continued to expand and then started to accumulate compressive strain. A qualitative model based on interaction between liquid Bi and Cu is developed to explain the observed creep behavior at temperatures higher than T-m,T-Bi. The results obtained here shed light on the creep behavior of alloys with constituents having significantly different creep behavior and containing a non-reacting liquid phase. (C) The Minerals, Metals & Materials Society and ASM International 201
Concurrent bi-lateral negotiation in agent systems
No full textBi-lateral negotiations represent an important class of encounter in agent-based systems. To this end, this paper develops and evaluates a heuristic model that enables an agent to participate in multiple, concurrent bi-lateral encounters in competitive situations in which there is information uncertainty and deadlines
Chemical Compositions Of Thin-Disk, High-Metallicity Red Horizontal-Branch Field Stars
No full textWe present a detailed abundance analysis and atmospheric parameters of 76 stars from a survey to identify field Galactic red horizontal-branch (RHB) stars. High-resolution echelle spectra (R similar or equal to 60,000, S/N >= 100) were obtained with the 2.7 m Harlan J. Smith Telescope at McDonald Observatory. The target stars were selected only by color and parallax information. Overall metallicities and relative abundances of proton-capture elements (C, N, O, Li), alpha-elements (Ca and Si), and neutron-capture elements (Eu and La) were determined by either equivalent width or synthetic spectrum analyses. We used CN features at the lambda lambda 7995-8040 region in order to determine the C-12/C-13 ratios of our targets. Investigation of the evolutionary stages, using spectroscopic T-eff and log g values along with derived C-12/C-13 ratios, revealed the presence of 18 probable RHB stars in our sample. We also derived kinematics of the stars with available distance information. Taking into account both the kinematics and probable evolutionary stages, we conclude that our sample contains 5 thick-disk and 13 thin-disk RHB stars. Up until now, RHB stars have been considered as members of the thick disk, and were expected to have large space velocities and sub-solar metallicities. However, our sample is dominated by low-velocity solar-metallicity RHB stars; their existence cannot be easily explained with standard stellar evolution.Scientific and Technological Research Council of Turkey (TUBITAK)NASAU.S. National Science Foundation AST 09-08978Rex G. Baker, Jr. endowmentAstronom
Temperature-dependent orbital physics in a spin-orbital-lattice-coupled 2p electron Mott system: The case of KO2
No full textWe have investigated the temperature (T)-dependent evolution of orbital states in a typical spin-orbital-lattice-coupled 2p electron Mott system KO2, based on the electronic structures obtained by the dynamical mean-field theory as well as the density functional theory. We have shown that KO2 exhibits the orbital fluctuation feature at high T due to degenerate pi(g)* orbitals. Upon cooling, the orbital fluctuation is suppressed by the Jahn-Teller-type crystal field that becomes stronger with the lowering of structural symmetry, and then the ferro-orbital (FO) ordering emerges at low T. This FO ordering feature distinguishes KO2 from RbO2 and CsO2 in that the latter two seem to have antiferro-orbital orderings at low T, indicating that the underlying physics is different between them. We propose that the suppression of the orbital fluctuation in KO2 can be observed by thermal-conductivity measurement, as observed in spin-orbital-lattice-coupled 3d transition-metal oxides such as LaVO3.open1166sciescopu
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