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101.
Central European Journal of Operations Research - Disaster management generally includes the post-disaster stage, which consists of the actions taken in response to the disaster damages. These...  相似文献   
102.
Some algebraic structures determined by the class (þ) of all effects of a Hilbert space þ and by some subclasses of (þ) are investigated, in particular de Morgan-Brouwer-Zadeh posets [it is proved that (þ n )(n<) has such a structure], Brouwer-Zadeh * posets (a quite trivial example consisting of suitable effects is given), and Brouwer-Zadeh 3 posets which are both de Morgan and *.It is shown that a nontrivial class of effects of a Hilbert space exists which is a BZ 3 poset. An -preclusivity relation on the set of all vectors of þ is introduced, and it is shown that it satisfies the regularity condition also for [1/2, 1].  相似文献   
103.
In a theory of local field algebras satisfying the split property, we introduce an algebra generated by the local energy-momentum operators obtained from the canonical local implementation of translations, and possibly by the local charges operators. We discuss the relations of this algebra to the given algebra of local observables and take some steps toward the characterization of theories where they coincide. In the presence of spontaneously broken symmetries, we present a no-go theorem.  相似文献   
104.
The decay rates for the exclusiveB decaysBK c andBK* c are calculated in the context of the heavy quark effective theory. We obtain(BK c )/ (BK)=1.6±0.2 and(BK* c )/ (K*)=0.39±0.04. These results lead to estimates BR(BK c )=(0.11±0.02)% and BR(BK* c )=(0.05±0.01)% if we use the central current experimental values forB(K, K *) branching ratios.  相似文献   
105.
A lagrangian euclidean model of Drinfeld-Sokolov (DS) reduction leading to generalW-algebras on a Riemann surface of any genus is presented. The background geometry is given by the DS principal bundleK associated to a complex Lie groupG and anSL(2,) subgroupS. The basic fields are a hermitian fiber metricH ofK and a (0, 1) Koszul gauge fieldA * ofK valued in a certain negative graded subalgebrar ofg related tos. The action governing theH andA * dynamics is the effective action of a DS field theory in the geometric background specified byH andA *. Quantization ofH andA * implements on one hand the DS reduction and on the other defines a novel model of 2d gravity, DS gravity. The gauge fixing of the DS gauge symmetry yields an integration on a moduli space of DS gauge equivalence classes ofA * configurations, the DS moduli space. The model has a residual gauge symmetry associated to the DS gauge transformations leaving a given fieldA * invariant. This is the DS counterpart of conformal symmetry. Conformal invariance and certain non-perturbative features of the model are discussed in detail.  相似文献   
106.
Lucifer yellow and lissamine rhodamine sulfonyl hydrazine were used as the donor and the receptor, respectively, for Förster energy transfer measurements to determine the location of the subunit in the native Na,K-ATPase from pig kidney. It was found that (1) the subunits are located in one functional complex, i.e., the dimer ()2 appears to be the functional complex of Na,K-ATPase, and (2) the subunits in the functional enzyme complex in the membrane are not located next to each other but are rather well separated. The distance between fluorophores covalently attached to the subunits was found to be 5.3 nm.  相似文献   
107.
We study some global projective properties of real plane curves with cusps, beaks and normal crossings. Starting from Fabricius-Bjerre's formula on the singularities of a curve in an affine plane, we describe its extension to a projective setting. Given a curve RP2, by fixing a base point we associate some indices to its singularities and double tangents. We prove two global relations linking these entities together.  相似文献   
108.
We characterize the automorphisms of aC *-algebra which extend to automorphisms of the crossed product by a compact group dual. The case where the inclusion is equipped with a group of automorphisms commuting with the dual action is also treated. These results are applied to the analysis of broken gauge symmetries in Quantum Field Theory to draw conclusions on the structure of the degenerate vacua on the field algebra.Dedicated to Huzihiro ArakiResearch supported by MURST and CNR, GNAFA  相似文献   
109.
The chromatographic resolution of enantiomeric amino acids is accomplished on a reversed phase column using aqueous mobile phase containing the chiral reagent N,N-dimethyl-S-phenylalanine-Cu(II). The separation is a result of the whole interaction between the diastereomeric complex surface and the mixed stationary phase realized by the dynamic coating of the RP-18 carbon chains layer. The elution order seems to be related to the different water coordination capability on copper ion in the formation of the mixed ternary complexes.  相似文献   
110.
The modification of a glassy carbon surface by coating with an electrostatically assembled film of tetraruthenated cobalt porphyrin/(meso-tetra(4-sulphonatephenyl)porphyrinate zinc(II) yields an indicator electrode that allows the determination of nitrite to be performed with a limit of detection of 0.1 μM in a flow injection configuration. The dynamic range extends up to 1000 μM and the repeatability of the measurements was evaluated to be 1.5% with a throughput of 50 samples per hour. The efficiency of the bilayered film to mediate the electron transfer allows the determinations to be performed at a less positive potential (+0.75 V) with enhanced sensitivity. The coating also prevents the surface poisoning and its stability is maintained over several weeks. The same detector was used for determination of nitrate after reduction to nitrite in a reductor column containing copperised cadmium. This method was used for the determination of nitrate and nitrite in mineral water, saliva and cured meats, the results being in agreement with certified values and those obtained by using recommended procedures.  相似文献   
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