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71.
The insurance situation in which an enormous risk is insured by a number of insurance companies is modeled through a cooperative TU game, the so-called co-insurance game, first introduced in Fragnelli and Marina (2004). In this paper we present certain conditions on the parameters of the model that guarantee the 1-convexity property of co-insurance games which in turn ensures the nonemptiness of the core and the linearity of the nucleolus as a function of the variable premium. Further we reveal conditions when a co-insurance game is representable in the form of a veto-removed game and present an efficient final algorithm for computing the nucleolus of a veto-removed game.  相似文献   
72.
73.
The breakup of an axisymmetric viscous jet is considered in the lubrication approximation. The discretised equations are solved on a fixed equidistant one-dimensional Eulerian grid. The governing equations are implemented in a conservative second order accurate total variation diminishing (TVD) scheme, preventing the numerical diffusivity. Singularities that occur at pinchoff and coalescence are regularised by a small modification on the surface tension. The modification is of the order of the spatial step Δx. This regularisation ensures that the solution of the presented numerical model converges to the exact solution of the breakup of a jet in the lubrication approximation. The results of the presented numerical model agree quantitatively with the analytical solution of the Rayleigh–Plateau instability, and with experimental results on the final stage of the Rayleigh–Plateau instability.  相似文献   
74.
Cu7PSe6 is a mixed conductor that crystallizes in the simple cubic structure at room temperature. Structural transitions above and below room temperature are accompanied by step-like changes in electrical conductivity. The substitution of Ag+ for Cu+ in Cu7PSe6 stabilized the simple cubic structure over a wider range of temperatures than is observed for the pure compound. A disproportionate decrease in electrical conductivity accompanies modest levels of silver substitution. The prominent step in electrical conductivity associated with the low-temperature crystallographic phase transition disappears in (AgxCu1−x)7PSe6 solid solutions for a composition parameter x=0.20, replaced by two distinct changes in the slope of conductivity below room temperature.  相似文献   
75.
Summary Reaction of the ligandN,N,N,N-tetrakis(pyrazol-l-yhnethyl)-1,2-diaminoethane (edtp) with Cu(MeCN)(BF4) produces the white crystalline solid [Cu(edtp)](BF4)(MeCN). The single-crystal x-ray diffraction showed chains of copper(I) ions linked to one another by edtp molecules. The copper ions are coordinated by four pyrazole nitrogens in an almost tetrahedral arrangement. The acetonitrile molecule and the tetrafluoroborate anion are not bound to the copper(I) ion. Crystal data: Orthorhombic space group Ima2,a=17.872(7),b=11.305(2),c=12.931(4) Å, Z=4, with R=0.038 (Rw = 0.46) for 1060 reflections with I > 2(I).  相似文献   
76.
A reversed-phase liquid chromatography (LC) method for narasin in feedingstuffs and premixtures was developed, validated, and interlaboratory studied. The extraction solvent was methanol-K2HPO4 solution (9 + 1, v/v). Narasin was detected at 600 nm after post-column derivatization with dimethylamino-benzaldehyde. Recovery was >90%. The repeatability (RSDr) in feed (20-140 mg/kg) ranged between 1.2 and 10.5%; the within-laboratory reproducibility (RSD(R)) ranged between 2.2 and 4.9%. The limit of determination was <20 mg/kg. Other feed additives did not interfere in the assay. The method showed ruggedness against changes in the composition of extraction solvent, eluent, and conditions for post-column reactions. In an interlaboratory study, 5 broiler feeds (4 positive, 1 blank) and 1 premixture were analyzed by 13 laboratories. The RSDr of the feedingstuffs (20-120 mg/kg) varied between 2.17 and 7.57%. The HORRAT ranged between 0.77 and 0.88, with recoveries between 82 and 104%. One laboratory detected small signals in the blank sample, calculated as 0.6 and 2.8 mg/kg. For the premixture, acceptable results for reproducibility could only be obtained after modification of the method: the RSDr was 4.42% and the HORRAT was 1.56 (12 laboratories).  相似文献   
77.
Propagation of a femtosecond pulse in a microresonator visualized in time   总被引:1,自引:0,他引:1  
A noninvasive pulse-tracking technique has been exploited to observe the time-resolved motion of an ultrashort light pulse within an integrated optical microresonator. We follow a pulse as it completes several round trips in the resonator, directly mapping the resonator modes in space and time. Our time-dependent and phase-sensitive measurement provides direct access to the angular group and phase velocity of the modes in the resonator. From the measurement the coupling constants between the access waveguides and the resonator are retrieved while at the same time the loss mechanisms throughout the structure are directly visualized.  相似文献   
78.
Bacteria use a communication system, called quorum sensing (QS), to organize into communities and synchronize gene expression to promote virulence and secure survival. Here we report on a proof-of-principle for externally interfering with this bacterial communication system, using light. By employing photoswitchable small molecules, we were able to photocontrol the QS-related bioluminescence in an Escherichia coli reporter strain, and the expression of target QS genes and pyocyanin production in Pseudomonas aeruginosa.  相似文献   
79.
A new linear value for cooperative transferable utility games is introduced. The recursive definition of the new value for an n-person game involves a sequential process performed at n − 1 stages, applying the value to subgames with a certain size k,1 ? k < n, combining with the rule of two-leveled egalitarianism (additive normalization) in order to guarantee the efficiency property for the new value, sequentially two-leveled egalitarianism, shortly S2EG value, applied to subgames of size k + 1. The new value will be characterized in various ways. The S2EG value differs from the Shapley value since, besides efficiency, linearity, and symmetry, it verifies an additional property with respect to so-called scale-dummy player (replacing dummy player property). Consequently, the S2EG value of a game may be determined as the solidarity value of the per-capita game (incorporating the proportional rule due to different levels of efficiency). Various potential representations of the new value are established. In the application to a land corn production economy, it yields allocations, in which the landlord’s interest coincides with striving for a maximum production level. For economies with the linear production function, not only the unique landlord but also all the workers have incentives to increase the scale of the economy.  相似文献   
80.
Abstract

The analysis, design, realization, and measurements of a novel intensity modulator are reported. The operating principle is based on mode coupling between a passive low-loss SiON waveguide and an electro-optic high-loss polymer waveguiding structure. Matching the waveguides is critical and results in severe demands for the technology. Extended simulations by the Coupled Mode Theory, the Leaky Wave Model, and Finite Difference Beam Propagation Method resulted in the design of several modulator structures. After realization, modulation could be demonstrated at 632 nm and at 1523 nm using lossy waveguiding modes and surface plasmon modes.  相似文献   
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